Welcome to mirror list, hosted at ThFree Co, Russian Federation.

cygwin.com/git/newlib-cygwin.git - Unnamed repository; edit this file 'description' to name the repository.
summaryrefslogtreecommitdiff
diff options
context:
space:
mode:
Diffstat (limited to 'winsup/cygwin/malloc.cc')
-rw-r--r--winsup/cygwin/malloc.cc5582
1 files changed, 0 insertions, 5582 deletions
diff --git a/winsup/cygwin/malloc.cc b/winsup/cygwin/malloc.cc
deleted file mode 100644
index 2e0a5cce0..000000000
--- a/winsup/cygwin/malloc.cc
+++ /dev/null
@@ -1,5582 +0,0 @@
-/*
- This is a version (aka dlmalloc) of malloc/free/realloc written by
- Doug Lea and released to the public domain. Use, modify, and
- redistribute this code without permission or acknowledgement in any
- way you wish. Send questions, comments, complaints, performance
- data, etc to dl@cs.oswego.edu
-
-* VERSION 2.7.2 Sat Aug 17 09:07:30 2002 Doug Lea (dl at gee)
-
- Note: There may be an updated version of this malloc obtainable at
- ftp://gee.cs.oswego.edu/pub/misc/malloc.c
- Check before installing!
-
-* Quickstart
-
- This library is all in one file to simplify the most common usage:
- ftp it, compile it (-O), and link it into another program. All
- of the compile-time options default to reasonable values for use on
- most unix platforms. Compile -DWIN32 for reasonable defaults on windows.
- You might later want to step through various compile-time and dynamic
- tuning options.
-
- For convenience, an include file for code using this malloc is at:
- ftp://gee.cs.oswego.edu/pub/misc/malloc-2.7.1.h
- You don't really need this .h file unless you call functions not
- defined in your system include files. The .h file contains only the
- excerpts from this file needed for using this malloc on ANSI C/C++
- systems, so long as you haven't changed compile-time options about
- naming and tuning parameters. If you do, then you can create your
- own malloc.h that does include all settings by cutting at the point
- indicated below.
-
-* Why use this malloc?
-
- This is not the fastest, most space-conserving, most portable, or
- most tunable malloc ever written. However it is among the fastest
- while also being among the most space-conserving, portable and tunable.
- Consistent balance across these factors results in a good general-purpose
- allocator for malloc-intensive programs.
-
- The main properties of the algorithms are:
- * For large (>= 512 bytes) requests, it is a pure best-fit allocator,
- with ties normally decided via FIFO (i.e. least recently used).
- * For small (<= 64 bytes by default) requests, it is a caching
- allocator, that maintains pools of quickly recycled chunks.
- * In between, and for combinations of large and small requests, it does
- the best it can trying to meet both goals at once.
- * For very large requests (>= 128KB by default), it relies on system
- memory mapping facilities, if supported.
-
- For a longer but slightly out of date high-level description, see
- http://gee.cs.oswego.edu/dl/html/malloc.html
-
- You may already by default be using a C library containing a malloc
- that is based on some version of this malloc (for example in
- linux). You might still want to use the one in this file in order to
- customize settings or to avoid overheads associated with library
- versions.
-
-* Contents, described in more detail in "description of public routines" below.
-
- Standard (ANSI/SVID/...) functions:
- malloc(size_t n);
- calloc(size_t n_elements, size_t element_size);
- free(Void_t* p);
- realloc(Void_t* p, size_t n);
- memalign(size_t alignment, size_t n);
- valloc(size_t n);
- mallinfo()
- mallopt(int parameter_number, int parameter_value)
-
- Additional functions:
- independent_calloc(size_t n_elements, size_t size, Void_t* chunks[]);
- independent_comalloc(size_t n_elements, size_t sizes[], Void_t* chunks[]);
- pvalloc(size_t n);
- cfree(Void_t* p);
- malloc_trim(size_t pad);
- malloc_usable_size(Void_t* p);
- malloc_stats();
-
-* Vital statistics:
-
- Supported pointer representation: 4 or 8 bytes
- Supported size_t representation: 4 or 8 bytes
- Note that size_t is allowed to be 4 bytes even if pointers are 8.
- You can adjust this by defining INTERNAL_SIZE_T
-
- Alignment: 2 * sizeof(size_t) (default)
- (i.e., 8 byte alignment with 4byte size_t). This suffices for
- nearly all current machines and C compilers. However, you can
- define MALLOC_ALIGNMENT to be wider than this if necessary.
-
- Minimum overhead per allocated chunk: 4 or 8 bytes
- Each malloced chunk has a hidden word of overhead holding size
- and status information.
-
- Minimum allocated size: 4-byte ptrs: 16 bytes (including 4 overhead)
- 8-byte ptrs: 24/32 bytes (including, 4/8 overhead)
-
- When a chunk is freed, 12 (for 4byte ptrs) or 20 (for 8 byte
- ptrs but 4 byte size) or 24 (for 8/8) additional bytes are
- needed; 4 (8) for a trailing size field and 8 (16) bytes for
- free list pointers. Thus, the minimum allocatable size is
- 16/24/32 bytes.
-
- Even a request for zero bytes (i.e., malloc(0)) returns a
- pointer to something of the minimum allocatable size.
-
- The maximum overhead wastage (i.e., number of extra bytes
- allocated than were requested in malloc) is less than or equal
- to the minimum size, except for requests >= mmap_threshold that
- are serviced via mmap(), where the worst case wastage is 2 *
- sizeof(size_t) bytes plus the remainder from a system page (the
- minimal mmap unit); typically 4096 or 8192 bytes.
-
- Maximum allocated size: 4-byte size_t: 2^32 minus about two pages
- 8-byte size_t: 2^64 minus about two pages
-
- It is assumed that (possibly signed) size_t values suffice to
- represent chunk sizes. `Possibly signed' is due to the fact
- that `size_t' may be defined on a system as either a signed or
- an unsigned type. The ISO C standard says that it must be
- unsigned, but a few systems are known not to adhere to this.
- Additionally, even when size_t is unsigned, sbrk (which is by
- default used to obtain memory from system) accepts signed
- arguments, and may not be able to handle size_t-wide arguments
- with negative sign bit. Generally, values that would
- appear as negative after accounting for overhead and alignment
- are supported only via mmap(), which does not have this
- limitation.
-
- Requests for sizes outside the allowed range will perform an optional
- failure action and then return null. (Requests may also
- also fail because a system is out of memory.)
-
- Thread-safety: NOT thread-safe unless USE_MALLOC_LOCK defined
-
- When USE_MALLOC_LOCK is defined, wrappers are created to
- surround every public call with either a pthread mutex or
- a win32 spinlock (depending on WIN32). This is not
- especially fast, and can be a major bottleneck.
- It is designed only to provide minimal protection
- in concurrent environments, and to provide a basis for
- extensions. If you are using malloc in a concurrent program,
- you would be far better off obtaining ptmalloc, which is
- derived from a version of this malloc, and is well-tuned for
- concurrent programs. (See http://www.malloc.de) Note that
- even when USE_MALLOC_LOCK is defined, you can can guarantee
- full thread-safety only if no threads acquire memory through
- direct calls to MORECORE or other system-level allocators.
-
- Compliance: I believe it is compliant with the 1997 Single Unix Specification
- (See http://www.opennc.org). Also SVID/XPG, ANSI C, and probably
- others as well.
-
-* Synopsis of compile-time options:
-
- People have reported using previous versions of this malloc on all
- versions of Unix, sometimes by tweaking some of the defines
- below. It has been tested most extensively on Solaris and
- Linux. It is also reported to work on WIN32 platforms.
- People also report using it in stand-alone embedded systems.
-
- The implementation is in straight, hand-tuned ANSI C. It is not
- at all modular. (Sorry!) It uses a lot of macros. To be at all
- usable, this code should be compiled using an optimizing compiler
- (for example gcc -O3) that can simplify expressions and control
- paths. (FAQ: some macros import variables as arguments rather than
- declare locals because people reported that some debuggers
- otherwise get confused.)
-
- OPTION DEFAULT VALUE
-
- Compilation Environment options:
-
- __STD_C derived from C compiler defines
- WIN32 NOT defined
- HAVE_MEMCPY defined
- USE_MEMCPY 1 if HAVE_MEMCPY is defined
- HAVE_MMAP defined as 1
- MMAP_CLEARS 1
- HAVE_MREMAP 0 unless linux defined
- malloc_getpagesize derived from system #includes, or 4096 if not
- HAVE_USR_INCLUDE_MALLOC_H NOT defined
- LACKS_UNISTD_H NOT defined unless WIN32
- LACKS_SYS_PARAM_H NOT defined unless WIN32
- LACKS_SYS_MMAN_H NOT defined unless WIN32
- LACKS_FCNTL_H NOT defined
-
- Changing default word sizes:
-
- INTERNAL_SIZE_T size_t
- MALLOC_ALIGNMENT 2 * sizeof(INTERNAL_SIZE_T)
- PTR_UINT unsigned long
- CHUNK_SIZE_T unsigned long
-
- Configuration and functionality options:
-
- USE_DL_PREFIX NOT defined
- USE_PUBLIC_MALLOC_WRAPPERS NOT defined
- USE_MALLOC_LOCK NOT defined
- DEBUG NOT defined
- REALLOC_ZERO_BYTES_FREES NOT defined
- MALLOC_FAILURE_ACTION errno = ENOMEM, if __STD_C defined, else no-op
- TRIM_FASTBINS 0
- FIRST_SORTED_BIN_SIZE 512
-
- Options for customizing MORECORE:
-
- MORECORE sbrk
- MORECORE_CONTIGUOUS 1
- MORECORE_CANNOT_TRIM NOT defined
- MMAP_AS_MORECORE_SIZE (1024 * 1024)
-
- Tuning options that are also dynamically changeable via mallopt:
-
- DEFAULT_MXFAST 64
- DEFAULT_TRIM_THRESHOLD 256 * 1024
- DEFAULT_TOP_PAD 0
- DEFAULT_MMAP_THRESHOLD 256 * 1024
- DEFAULT_MMAP_MAX 65536
-
- There are several other #defined constants and macros that you
- probably don't want to touch unless you are extending or adapting malloc.
-*/
-
-/*
- WIN32 sets up defaults for MS environment and compilers.
- Otherwise defaults are for unix.
-*/
-
-/* #define WIN32 */
-
-#ifdef WIN32
-
-#define WIN32_LEAN_AND_MEAN
-#include <windows.h>
-
-/* Win32 doesn't supply or need the following headers */
-#define LACKS_UNISTD_H
-#define LACKS_SYS_PARAM_H
-#define LACKS_SYS_MMAN_H
-
-/* Use the supplied emulation of sbrk */
-#define MORECORE sbrk
-#define MORECORE_CONTIGUOUS 1
-#define MORECORE_FAILURE ((void*)(-1))
-
-/* Use the supplied emulation of mmap and munmap */
-#define HAVE_MMAP 1
-#define MUNMAP_FAILURE (-1)
-#define MMAP_CLEARS 1
-
-/* These values don't really matter in windows mmap emulation */
-#define MAP_PRIVATE 1
-#define MAP_ANONYMOUS 2
-#define PROT_READ 1
-#define PROT_WRITE 2
-
-/* Emulation functions defined at the end of this file */
-
-/* If USE_MALLOC_LOCK, use supplied critical-section-based lock functions */
-#ifdef USE_MALLOC_LOCK
-static int slwait(int *sl);
-static int slrelease(int *sl);
-#endif
-
-static long getpagesize(void);
-static long getregionsize(void);
-static void *sbrk(long size);
-static void *mmap(void *ptr, long size, long prot, long type, long handle, long arg);
-static long munmap(void *ptr, long size);
-
-static void vminfo (unsigned long*free, unsigned long*reserved, unsigned long*committed);
-static int cpuinfo (int whole, unsigned long*kernel, unsigned long*user);
-
-#endif
-
-/*
- __STD_C should be nonzero if using ANSI-standard C compiler, a C++
- compiler, or a C compiler sufficiently close to ANSI to get away
- with it.
-*/
-
-#ifndef __STD_C
-#if defined(__STDC__) || defined(_cplusplus)
-#define __STD_C 1
-#else
-#define __STD_C 0
-#endif
-#endif /*__STD_C*/
-
-
-/*
- Void_t* is the pointer type that malloc should say it returns
-*/
-
-#ifndef Void_t
-#if (__STD_C || defined(WIN32))
-#define Void_t void
-#else
-#define Void_t char
-#endif
-#endif /*Void_t*/
-
-#if __STD_C
-#include <stddef.h> /* for size_t */
-#else
-#include <sys/types.h>
-#endif
-
-#include "cygmalloc.h"
-
-#ifdef __cplusplus
-extern "C" {
-#endif
-
-/* define LACKS_UNISTD_H if your system does not have a <unistd.h>. */
-
-/* #define LACKS_UNISTD_H */
-
-#ifndef LACKS_UNISTD_H
-#include <unistd.h>
-#endif
-
-/* define LACKS_SYS_PARAM_H if your system does not have a <sys/param.h>. */
-
-/* #define LACKS_SYS_PARAM_H */
-
-
-#include <stdio.h> /* needed for malloc_stats */
-#include <errno.h> /* needed for optional MALLOC_FAILURE_ACTION */
-
-
-/*
- Debugging:
-
- Because freed chunks may be overwritten with bookkeeping fields, this
- malloc will often die when freed memory is overwritten by user
- programs. This can be very effective (albeit in an annoying way)
- in helping track down dangling pointers.
-
- If you compile with -DDEBUG, a number of assertion checks are
- enabled that will catch more memory errors. You probably won't be
- able to make much sense of the actual assertion errors, but they
- should help you locate incorrectly overwritten memory. The
- checking is fairly extensive, and will slow down execution
- noticeably. Calling malloc_stats or mallinfo with DEBUG set will
- attempt to check every non-mmapped allocated and free chunk in the
- course of computing the summmaries. (By nature, mmapped regions
- cannot be checked very much automatically.)
-
- Setting DEBUG may also be helpful if you are trying to modify
- this code. The assertions in the check routines spell out in more
- detail the assumptions and invariants underlying the algorithms.
-
- Setting DEBUG does NOT provide an automated mechanism for checking
- that all accesses to malloced memory stay within their
- bounds. However, there are several add-ons and adaptations of this
- or other mallocs available that do this.
-*/
-
-#if DEBUG
-#include <assert.h>
-#else
-#define assert(x) ((void)0)
-#endif
-
-/*
- The unsigned integer type used for comparing any two chunk sizes.
- This should be at least as wide as size_t, but should not be signed.
-*/
-
-#ifndef CHUNK_SIZE_T
-#define CHUNK_SIZE_T unsigned long
-#endif
-
-/*
- The unsigned integer type used to hold addresses when they are are
- manipulated as integers. Except that it is not defined on all
- systems, intptr_t would suffice.
-*/
-#ifndef PTR_UINT
-#define PTR_UINT unsigned long
-#endif
-
-
-/*
- INTERNAL_SIZE_T is the word-size used for internal bookkeeping
- of chunk sizes.
-
- The default version is the same as size_t.
-
- While not strictly necessary, it is best to define this as an
- unsigned type, even if size_t is a signed type. This may avoid some
- artificial size limitations on some systems.
-
- On a 64-bit machine, you may be able to reduce malloc overhead by
- defining INTERNAL_SIZE_T to be a 32 bit `unsigned int' at the
- expense of not being able to handle more than 2^32 of malloced
- space. If this limitation is acceptable, you are encouraged to set
- this unless you are on a platform requiring 16byte alignments. In
- this case the alignment requirements turn out to negate any
- potential advantages of decreasing size_t word size.
-
- Implementors: Beware of the possible combinations of:
- - INTERNAL_SIZE_T might be signed or unsigned, might be 32 or 64 bits,
- and might be the same width as int or as long
- - size_t might have different width and signedness as INTERNAL_SIZE_T
- - int and long might be 32 or 64 bits, and might be the same width
- To deal with this, most comparisons and difference computations
- among INTERNAL_SIZE_Ts should cast them to CHUNK_SIZE_T, being
- aware of the fact that casting an unsigned int to a wider long does
- not sign-extend. (This also makes checking for negative numbers
- awkward.) Some of these casts result in harmless compiler warnings
- on some systems.
-*/
-
-#ifndef INTERNAL_SIZE_T
-#define INTERNAL_SIZE_T size_t
-#endif
-
-/* The corresponding word size */
-#define SIZE_SZ (sizeof(INTERNAL_SIZE_T))
-
-
-
-/*
- MALLOC_ALIGNMENT is the minimum alignment for malloc'ed chunks.
- It must be a power of two at least 2 * SIZE_SZ, even on machines
- for which smaller alignments would suffice. It may be defined as
- larger than this though. Note however that code and data structures
- are optimized for the case of 8-byte alignment.
-*/
-
-
-#ifndef MALLOC_ALIGNMENT
-#define MALLOC_ALIGNMENT (2 * SIZE_SZ)
-#endif
-
-/* The corresponding bit mask value */
-#define MALLOC_ALIGN_MASK (MALLOC_ALIGNMENT - 1)
-
-
-
-/*
- REALLOC_ZERO_BYTES_FREES should be set if a call to
- realloc with zero bytes should be the same as a call to free.
- Some people think it should. Otherwise, since this malloc
- returns a unique pointer for malloc(0), so does realloc(p, 0).
-*/
-
-/* #define REALLOC_ZERO_BYTES_FREES */
-
-/*
- TRIM_FASTBINS controls whether free() of a very small chunk can
- immediately lead to trimming. Setting to true (1) can reduce memory
- footprint, but will almost always slow down programs that use a lot
- of small chunks.
-
- Define this only if you are willing to give up some speed to more
- aggressively reduce system-level memory footprint when releasing
- memory in programs that use many small chunks. You can get
- essentially the same effect by setting MXFAST to 0, but this can
- lead to even greater slowdowns in programs using many small chunks.
- TRIM_FASTBINS is an in-between compile-time option, that disables
- only those chunks bordering topmost memory from being placed in
- fastbins.
-*/
-
-#ifndef TRIM_FASTBINS
-#define TRIM_FASTBINS 0
-#endif
-
-
-/*
- USE_DL_PREFIX will prefix all public routines with the string 'dl'.
- This is necessary when you only want to use this malloc in one part
- of a program, using your regular system malloc elsewhere.
-*/
-
-/* #define USE_DL_PREFIX */
-
-
-/*
- USE_MALLOC_LOCK causes wrapper functions to surround each
- callable routine with pthread mutex lock/unlock.
-
- USE_MALLOC_LOCK forces USE_PUBLIC_MALLOC_WRAPPERS to be defined
-*/
-
-
-/* #define USE_MALLOC_LOCK */
-
-
-/*
- If USE_PUBLIC_MALLOC_WRAPPERS is defined, every public routine is
- actually a wrapper function that first calls MALLOC_PREACTION, then
- calls the internal routine, and follows it with
- MALLOC_POSTACTION. This is needed for locking, but you can also use
- this, without USE_MALLOC_LOCK, for purposes of interception,
- instrumentation, etc. It is a sad fact that using wrappers often
- noticeably degrades performance of malloc-intensive programs.
-*/
-
-#ifdef USE_MALLOC_LOCK
-#define USE_PUBLIC_MALLOC_WRAPPERS
-#else
-/* #define USE_PUBLIC_MALLOC_WRAPPERS */
-#endif
-
-
-/*
- Two-phase name translation.
- All of the actual routines are given mangled names.
- When wrappers are used, they become the public callable versions.
- When DL_PREFIX is used, the callable names are prefixed.
-*/
-
-#ifndef USE_PUBLIC_MALLOC_WRAPPERS
-#define cALLOc public_cALLOc
-#define fREe public_fREe
-#define cFREe public_cFREe
-#define mALLOc public_mALLOc
-#define mEMALIGn public_mEMALIGn
-#define rEALLOc public_rEALLOc
-#define vALLOc public_vALLOc
-#define pVALLOc public_pVALLOc
-#define mALLINFo public_mALLINFo
-#define mALLOPt public_mALLOPt
-#define mTRIm public_mTRIm
-#define mSTATs public_mSTATs
-#define mUSABLe public_mUSABLe
-#define iCALLOc public_iCALLOc
-#define iCOMALLOc public_iCOMALLOc
-#endif
-
-#ifdef USE_DL_PREFIX
-#define public_cALLOc dlcalloc
-#define public_fREe dlfree
-#define public_cFREe dlcfree
-#define public_mALLOc dlmalloc
-#define public_mEMALIGn dlmemalign
-#define public_rEALLOc dlrealloc
-#define public_vALLOc dlvalloc
-#define public_pVALLOc dlpvalloc
-#define public_mALLINFo dlmallinfo
-#define public_mALLOPt dlmallopt
-#define public_mTRIm dlmalloc_trim
-#define public_mSTATs dlmalloc_stats
-#define public_mUSABLe dlmalloc_usable_size
-#define public_iCALLOc dlindependent_calloc
-#define public_iCOMALLOc dlindependent_comalloc
-#else /* USE_DL_PREFIX */
-#define public_cALLOc calloc
-#define public_fREe free
-#define public_cFREe cfree
-#define public_mALLOc malloc
-#define public_mEMALIGn memalign
-#define public_rEALLOc realloc
-#define public_vALLOc valloc
-#define public_pVALLOc pvalloc
-#define public_mALLINFo mallinfo
-#define public_mALLOPt mallopt
-#define public_mTRIm malloc_trim
-#define public_mSTATs malloc_stats
-#define public_mUSABLe malloc_usable_size
-#define public_iCALLOc independent_calloc
-#define public_iCOMALLOc independent_comalloc
-#endif /* USE_DL_PREFIX */
-
-
-/*
- HAVE_MEMCPY should be defined if you are not otherwise using
- ANSI STD C, but still have memcpy and memset in your C library
- and want to use them in calloc and realloc. Otherwise simple
- macro versions are defined below.
-
- USE_MEMCPY should be defined as 1 if you actually want to
- have memset and memcpy called. People report that the macro
- versions are faster than libc versions on some systems.
-
- Even if USE_MEMCPY is set to 1, loops to copy/clear small chunks
- (of <= 36 bytes) are manually unrolled in realloc and calloc.
-*/
-
-#define HAVE_MEMCPY
-
-#ifndef USE_MEMCPY
-#ifdef HAVE_MEMCPY
-#define USE_MEMCPY 1
-#else
-#define USE_MEMCPY 0
-#endif
-#endif
-
-
-#if (__STD_C || defined(HAVE_MEMCPY))
-
-#ifdef WIN32
-/* On Win32 memset and memcpy are already declared in windows.h */
-#else
-#if __STD_C
-void* memset(void*, int, size_t);
-void* memcpy(void*, const void*, size_t);
-#else
-Void_t* memset();
-Void_t* memcpy();
-#endif
-#endif
-#endif
-
-/*
- MALLOC_FAILURE_ACTION is the action to take before "return 0" when
- malloc fails to be able to return memory, either because memory is
- exhausted or because of illegal arguments.
-
- By default, sets errno if running on STD_C platform, else does nothing.
-*/
-
-#ifndef MALLOC_FAILURE_ACTION
-#if __STD_C
-#define MALLOC_FAILURE_ACTION \
- errno = ENOMEM;
-
-#else
-#define MALLOC_FAILURE_ACTION
-#endif
-#endif
-
-/*
- MORECORE-related declarations. By default, rely on sbrk
-*/
-
-
-#ifdef LACKS_UNISTD_H
-#if !defined(__FreeBSD__) && !defined(__OpenBSD__) && !defined(__NetBSD__)
-#if __STD_C
-extern Void_t* sbrk(ptrdiff_t);
-#else
-extern Void_t* sbrk();
-#endif
-#endif
-#endif
-
-/*
- MORECORE is the name of the routine to call to obtain more memory
- from the system. See below for general guidance on writing
- alternative MORECORE functions, as well as a version for WIN32 and a
- sample version for pre-OSX macos.
-*/
-
-#ifndef MORECORE
-#define MORECORE sbrk
-#endif
-
-/*
- MORECORE_FAILURE is the value returned upon failure of MORECORE
- as well as mmap. Since it cannot be an otherwise valid memory address,
- and must reflect values of standard sys calls, you probably ought not
- try to redefine it.
-*/
-
-#ifndef MORECORE_FAILURE
-#define MORECORE_FAILURE (-1)
-#endif
-
-/*
- If MORECORE_CONTIGUOUS is true, take advantage of fact that
- consecutive calls to MORECORE with positive arguments always return
- contiguous increasing addresses. This is true of unix sbrk. Even
- if not defined, when regions happen to be contiguous, malloc will
- permit allocations spanning regions obtained from different
- calls. But defining this when applicable enables some stronger
- consistency checks and space efficiencies.
-*/
-
-#ifndef MORECORE_CONTIGUOUS
-#define MORECORE_CONTIGUOUS 1
-#endif
-
-/*
- Define MORECORE_CANNOT_TRIM if your version of MORECORE
- cannot release space back to the system when given negative
- arguments. This is generally necessary only if you are using
- a hand-crafted MORECORE function that cannot handle negative arguments.
-*/
-
-/* #define MORECORE_CANNOT_TRIM */
-
-
-/*
- Define HAVE_MMAP as true to optionally make malloc() use mmap() to
- allocate very large blocks. These will be returned to the
- operating system immediately after a free(). Also, if mmap
- is available, it is used as a backup strategy in cases where
- MORECORE fails to provide space from system.
-
- This malloc is best tuned to work with mmap for large requests.
- If you do not have mmap, operations involving very large chunks (1MB
- or so) may be slower than you'd like.
-*/
-
-#ifndef HAVE_MMAP
-#define HAVE_MMAP 1
-#endif
-
-#if HAVE_MMAP
-/*
- Standard unix mmap using /dev/zero clears memory so calloc doesn't
- need to.
-*/
-
-#ifndef MMAP_CLEARS
-#define MMAP_CLEARS 1
-#endif
-
-#else /* no mmap */
-#ifndef MMAP_CLEARS
-#define MMAP_CLEARS 0
-#endif
-#endif
-
-
-/*
- MMAP_AS_MORECORE_SIZE is the minimum mmap size argument to use if
- sbrk fails, and mmap is used as a backup (which is done only if
- HAVE_MMAP). The value must be a multiple of page size. This
- backup strategy generally applies only when systems have "holes" in
- address space, so sbrk cannot perform contiguous expansion, but
- there is still space available on system. On systems for which
- this is known to be useful (i.e. most linux kernels), this occurs
- only when programs allocate huge amounts of memory. Between this,
- and the fact that mmap regions tend to be limited, the size should
- be large, to avoid too many mmap calls and thus avoid running out
- of kernel resources.
-*/
-
-#ifndef MMAP_AS_MORECORE_SIZE
-#define MMAP_AS_MORECORE_SIZE (1024 * 1024)
-#endif
-
-/*
- Define HAVE_MREMAP to make realloc() use mremap() to re-allocate
- large blocks. This is currently only possible on Linux with
- kernel versions newer than 1.3.77.
-*/
-
-#ifndef HAVE_MREMAP
-#ifdef linux
-#define HAVE_MREMAP 1
-#else
-#define HAVE_MREMAP 0
-#endif
-
-#endif /* HAVE_MMAP */
-
-
-/*
- The system page size. To the extent possible, this malloc manages
- memory from the system in page-size units. Note that this value is
- cached during initialization into a field of malloc_state. So even
- if malloc_getpagesize is a function, it is only called once.
-
- The following mechanics for getpagesize were adapted from bsd/gnu
- getpagesize.h. If none of the system-probes here apply, a value of
- 4096 is used, which should be OK: If they don't apply, then using
- the actual value probably doesn't impact performance.
-*/
-
-
-#ifndef malloc_getpagesize
-
-#ifndef LACKS_UNISTD_H
-# include <unistd.h>
-#endif
-
-# ifdef _SC_PAGESIZE /* some SVR4 systems omit an underscore */
-# ifndef _SC_PAGE_SIZE
-# define _SC_PAGE_SIZE _SC_PAGESIZE
-# endif
-# endif
-
-# ifdef _SC_PAGE_SIZE
-# define malloc_getpagesize sysconf(_SC_PAGE_SIZE)
-# else
-# if defined(BSD) || defined(DGUX) || defined(HAVE_GETPAGESIZE)
- extern size_t getpagesize();
-# define malloc_getpagesize getpagesize()
-# else
-# ifdef WIN32 /* use supplied emulation of getpagesize */
-# define malloc_getpagesize getpagesize()
-# else
-# ifndef LACKS_SYS_PARAM_H
-# include <sys/param.h>
-# endif
-# ifdef EXEC_PAGESIZE
-# define malloc_getpagesize EXEC_PAGESIZE
-# else
-# ifdef NBPG
-# ifndef CLSIZE
-# define malloc_getpagesize NBPG
-# else
-# define malloc_getpagesize (NBPG * CLSIZE)
-# endif
-# else
-# ifdef NBPC
-# define malloc_getpagesize NBPC
-# else
-# ifdef PAGESIZE
-# define malloc_getpagesize PAGESIZE
-# else /* just guess */
-# define malloc_getpagesize (4096)
-# endif
-# endif
-# endif
-# endif
-# endif
-# endif
-# endif
-#endif
-
-/*
- This version of malloc supports the standard SVID/XPG mallinfo
- routine that returns a struct containing usage properties and
- statistics. It should work on any SVID/XPG compliant system that has
- a /usr/include/malloc.h defining struct mallinfo. (If you'd like to
- install such a thing yourself, cut out the preliminary declarations
- as described above and below and save them in a malloc.h file. But
- there's no compelling reason to bother to do this.)
-
- The main declaration needed is the mallinfo struct that is returned
- (by-copy) by mallinfo(). The SVID/XPG malloinfo struct contains a
- bunch of fields that are not even meaningful in this version of
- malloc. These fields are are instead filled by mallinfo() with
- other numbers that might be of interest.
-
- HAVE_USR_INCLUDE_MALLOC_H should be set if you have a
- /usr/include/malloc.h file that includes a declaration of struct
- mallinfo. If so, it is included; else an SVID2/XPG2 compliant
- version is declared below. These must be precisely the same for
- mallinfo() to work. The original SVID version of this struct,
- defined on most systems with mallinfo, declares all fields as
- ints. But some others define as unsigned long. If your system
- defines the fields using a type of different width than listed here,
- you must #include your system version and #define
- HAVE_USR_INCLUDE_MALLOC_H.
-*/
-
-/* #define HAVE_USR_INCLUDE_MALLOC_H */
-
-#ifdef HAVE_USR_INCLUDE_MALLOC_H
-#include "/usr/include/malloc.h"
-#else
-
-/* SVID2/XPG mallinfo structure */
-
-struct mallinfo {
- int arena; /* non-mmapped space allocated from system */
- int ordblks; /* number of free chunks */
- int smblks; /* number of fastbin blocks */
- int hblks; /* number of mmapped regions */
- int hblkhd; /* space in mmapped regions */
- int usmblks; /* maximum total allocated space */
- int fsmblks; /* space available in freed fastbin blocks */
- int uordblks; /* total allocated space */
- int fordblks; /* total free space */
- int keepcost; /* top-most, releasable (via malloc_trim) space */
-};
-
-/*
- SVID/XPG defines four standard parameter numbers for mallopt,
- normally defined in malloc.h. Only one of these (M_MXFAST) is used
- in this malloc. The others (M_NLBLKS, M_GRAIN, M_KEEP) don't apply,
- so setting them has no effect. But this malloc also supports other
- options in mallopt described below.
-*/
-#endif
-
-
-/* ---------- description of public routines ------------ */
-
-/*
- malloc(size_t n)
- Returns a pointer to a newly allocated chunk of at least n bytes, or null
- if no space is available. Additionally, on failure, errno is
- set to ENOMEM on ANSI C systems.
-
- If n is zero, malloc returns a minumum-sized chunk. (The minimum
- size is 16 bytes on most 32bit systems, and 24 or 32 bytes on 64bit
- systems.) On most systems, size_t is an unsigned type, so calls
- with negative arguments are interpreted as requests for huge amounts
- of space, which will often fail. The maximum supported value of n
- differs across systems, but is in all cases less than the maximum
- representable value of a size_t.
-*/
-#if __STD_C
-Void_t* public_mALLOc(size_t);
-#else
-Void_t* public_mALLOc();
-#endif
-
-/*
- free(Void_t* p)
- Releases the chunk of memory pointed to by p, that had been previously
- allocated using malloc or a related routine such as realloc.
- It has no effect if p is null. It can have arbitrary (i.e., bad!)
- effects if p has already been freed.
-
- Unless disabled (using mallopt), freeing very large spaces will
- when possible, automatically trigger operations that give
- back unused memory to the system, thus reducing program footprint.
-*/
-#if __STD_C
-void public_fREe(Void_t*);
-#else
-void public_fREe();
-#endif
-
-/*
- calloc(size_t n_elements, size_t element_size);
- Returns a pointer to n_elements * element_size bytes, with all locations
- set to zero.
-*/
-#if __STD_C
-Void_t* public_cALLOc(size_t, size_t);
-#else
-Void_t* public_cALLOc();
-#endif
-
-/*
- realloc(Void_t* p, size_t n)
- Returns a pointer to a chunk of size n that contains the same data
- as does chunk p up to the minimum of (n, p's size) bytes, or null
- if no space is available.
-
- The returned pointer may or may not be the same as p. The algorithm
- prefers extending p when possible, otherwise it employs the
- equivalent of a malloc-copy-free sequence.
-
- If p is null, realloc is equivalent to malloc.
-
- If space is not available, realloc returns null, errno is set (if on
- ANSI) and p is NOT freed.
-
- if n is for fewer bytes than already held by p, the newly unused
- space is lopped off and freed if possible. Unless the #define
- REALLOC_ZERO_BYTES_FREES is set, realloc with a size argument of
- zero (re)allocates a minimum-sized chunk.
-
- Large chunks that were internally obtained via mmap will always
- be reallocated using malloc-copy-free sequences unless
- the system supports MREMAP (currently only linux).
-
- The old unix realloc convention of allowing the last-free'd chunk
- to be used as an argument to realloc is not supported.
-*/
-#if __STD_C
-Void_t* public_rEALLOc(Void_t*, size_t);
-#else
-Void_t* public_rEALLOc();
-#endif
-
-/*
- memalign(size_t alignment, size_t n);
- Returns a pointer to a newly allocated chunk of n bytes, aligned
- in accord with the alignment argument.
-
- The alignment argument should be a power of two. If the argument is
- not a power of two, the nearest greater power is used.
- 8-byte alignment is guaranteed by normal malloc calls, so don't
- bother calling memalign with an argument of 8 or less.
-
- Overreliance on memalign is a sure way to fragment space.
-*/
-#if __STD_C
-Void_t* public_mEMALIGn(size_t, size_t);
-#else
-Void_t* public_mEMALIGn();
-#endif
-
-/*
- valloc(size_t n);
- Equivalent to memalign(pagesize, n), where pagesize is the page
- size of the system. If the pagesize is unknown, 4096 is used.
-*/
-#if __STD_C
-Void_t* public_vALLOc(size_t);
-#else
-Void_t* public_vALLOc();
-#endif
-
-
-
-/*
- mallopt(int parameter_number, int parameter_value)
- Sets tunable parameters The format is to provide a
- (parameter-number, parameter-value) pair. mallopt then sets the
- corresponding parameter to the argument value if it can (i.e., so
- long as the value is meaningful), and returns 1 if successful else
- 0. SVID/XPG/ANSI defines four standard param numbers for mallopt,
- normally defined in malloc.h. Only one of these (M_MXFAST) is used
- in this malloc. The others (M_NLBLKS, M_GRAIN, M_KEEP) don't apply,
- so setting them has no effect. But this malloc also supports four
- other options in mallopt. See below for details. Briefly, supported
- parameters are as follows (listed defaults are for "typical"
- configurations).
-
- Symbol param # default allowed param values
- M_MXFAST 1 64 0-80 (0 disables fastbins)
- M_TRIM_THRESHOLD -1 256*1024 any (-1U disables trimming)
- M_TOP_PAD -2 0 any
- M_MMAP_THRESHOLD -3 256*1024 any (or 0 if no MMAP support)
- M_MMAP_MAX -4 65536 any (0 disables use of mmap)
-*/
-#if __STD_C
-int public_mALLOPt(int, int);
-#else
-int public_mALLOPt();
-#endif
-
-
-/*
- mallinfo()
- Returns (by copy) a struct containing various summary statistics:
-
- arena: current total non-mmapped bytes allocated from system
- ordblks: the number of free chunks
- smblks: the number of fastbin blocks (i.e., small chunks that
- have been freed but not use resused or consolidated)
- hblks: current number of mmapped regions
- hblkhd: total bytes held in mmapped regions
- usmblks: the maximum total allocated space. This will be greater
- than current total if trimming has occurred.
- fsmblks: total bytes held in fastbin blocks
- uordblks: current total allocated space (normal or mmapped)
- fordblks: total free space
- keepcost: the maximum number of bytes that could ideally be released
- back to system via malloc_trim. ("ideally" means that
- it ignores page restrictions etc.)
-
- Because these fields are ints, but internal bookkeeping may
- be kept as longs, the reported values may wrap around zero and
- thus be inaccurate.
-*/
-#if __STD_C
-struct mallinfo public_mALLINFo(void);
-#else
-struct mallinfo public_mALLINFo();
-#endif
-
-/*
- independent_calloc(size_t n_elements, size_t element_size, Void_t* chunks[]);
-
- independent_calloc is similar to calloc, but instead of returning a
- single cleared space, it returns an array of pointers to n_elements
- independent elements that can hold contents of size elem_size, each
- of which starts out cleared, and can be independently freed,
- realloc'ed etc. The elements are guaranteed to be adjacently
- allocated (this is not guaranteed to occur with multiple callocs or
- mallocs), which may also improve cache locality in some
- applications.
-
- The "chunks" argument is optional (i.e., may be null, which is
- probably the most typical usage). If it is null, the returned array
- is itself dynamically allocated and should also be freed when it is
- no longer needed. Otherwise, the chunks array must be of at least
- n_elements in length. It is filled in with the pointers to the
- chunks.
-
- In either case, independent_calloc returns this pointer array, or
- null if the allocation failed. If n_elements is zero and "chunks"
- is null, it returns a chunk representing an array with zero elements
- (which should be freed if not wanted).
-
- Each element must be individually freed when it is no longer
- needed. If you'd like to instead be able to free all at once, you
- should instead use regular calloc and assign pointers into this
- space to represent elements. (In this case though, you cannot
- independently free elements.)
-
- independent_calloc simplifies and speeds up implementations of many
- kinds of pools. It may also be useful when constructing large data
- structures that initially have a fixed number of fixed-sized nodes,
- but the number is not known at compile time, and some of the nodes
- may later need to be freed. For example:
-
- struct Node { int item; struct Node* next; };
-
- struct Node* build_list() {
- struct Node** pool;
- int n = read_number_of_nodes_needed();
- if (n <= 0) return 0;
- pool = (struct Node**)(independent_calloc(n, sizeof(struct Node), 0);
- if (pool == 0) die();
- // organize into a linked list...
- struct Node* first = pool[0];
- for (i = 0; i < n-1; ++i)
- pool[i]->next = pool[i+1];
- free(pool); // Can now free the array (or not, if it is needed later)
- return first;
- }
-*/
-#if __STD_C
-Void_t** public_iCALLOc(size_t, size_t, Void_t**);
-#else
-Void_t** public_iCALLOc();
-#endif
-
-/*
- independent_comalloc(size_t n_elements, size_t sizes[], Void_t* chunks[]);
-
- independent_comalloc allocates, all at once, a set of n_elements
- chunks with sizes indicated in the "sizes" array. It returns
- an array of pointers to these elements, each of which can be
- independently freed, realloc'ed etc. The elements are guaranteed to
- be adjacently allocated (this is not guaranteed to occur with
- multiple callocs or mallocs), which may also improve cache locality
- in some applications.
-
- The "chunks" argument is optional (i.e., may be null). If it is null
- the returned array is itself dynamically allocated and should also
- be freed when it is no longer needed. Otherwise, the chunks array
- must be of at least n_elements in length. It is filled in with the
- pointers to the chunks.
-
- In either case, independent_comalloc returns this pointer array, or
- null if the allocation failed. If n_elements is zero and chunks is
- null, it returns a chunk representing an array with zero elements
- (which should be freed if not wanted).
-
- Each element must be individually freed when it is no longer
- needed. If you'd like to instead be able to free all at once, you
- should instead use a single regular malloc, and assign pointers at
- particular offsets in the aggregate space. (In this case though, you
- cannot independently free elements.)
-
- independent_comallac differs from independent_calloc in that each
- element may have a different size, and also that it does not
- automatically clear elements.
-
- independent_comalloc can be used to speed up allocation in cases
- where several structs or objects must always be allocated at the
- same time. For example:
-
- struct Head { ... }
- struct Foot { ... }
-
- void send_message(char* msg) {
- int msglen = strlen(msg);
- size_t sizes[3] = { sizeof(struct Head), msglen, sizeof(struct Foot) };
- void* chunks[3];
- if (independent_comalloc(3, sizes, chunks) == 0)
- die();
- struct Head* head = (struct Head*)(chunks[0]);
- char* body = (char*)(chunks[1]);
- struct Foot* foot = (struct Foot*)(chunks[2]);
- // ...
- }
-
- In general though, independent_comalloc is worth using only for
- larger values of n_elements. For small values, you probably won't
- detect enough difference from series of malloc calls to bother.
-
- Overuse of independent_comalloc can increase overall memory usage,
- since it cannot reuse existing noncontiguous small chunks that
- might be available for some of the elements.
-*/
-#if __STD_C
-Void_t** public_iCOMALLOc(size_t, size_t*, Void_t**);
-#else
-Void_t** public_iCOMALLOc();
-#endif
-
-
-/*
- pvalloc(size_t n);
- Equivalent to valloc(minimum-page-that-holds(n)), that is,
- round up n to nearest pagesize.
- */
-#if __STD_C
-Void_t* public_pVALLOc(size_t);
-#else
-Void_t* public_pVALLOc();
-#endif
-
-/*
- cfree(Void_t* p);
- Equivalent to free(p).
-
- cfree is needed/defined on some systems that pair it with calloc,
- for odd historical reasons (such as: cfree is used in example
- code in the first edition of K&R).
-*/
-#if __STD_C
-void public_cFREe(Void_t*);
-#else
-void public_cFREe();
-#endif
-
-/*
- malloc_trim(size_t pad);
-
- If possible, gives memory back to the system (via negative
- arguments to sbrk) if there is unused memory at the `high' end of
- the malloc pool. You can call this after freeing large blocks of
- memory to potentially reduce the system-level memory requirements
- of a program. However, it cannot guarantee to reduce memory. Under
- some allocation patterns, some large free blocks of memory will be
- locked between two used chunks, so they cannot be given back to
- the system.
-
- The `pad' argument to malloc_trim represents the amount of free
- trailing space to leave untrimmed. If this argument is zero,
- only the minimum amount of memory to maintain internal data
- structures will be left (one page or less). Non-zero arguments
- can be supplied to maintain enough trailing space to service
- future expected allocations without having to re-obtain memory
- from the system.
-
- Malloc_trim returns 1 if it actually released any memory, else 0.
- On systems that do not support "negative sbrks", it will always
- rreturn 0.
-*/
-#if __STD_C
-int public_mTRIm(size_t);
-#else
-int public_mTRIm();
-#endif
-
-/*
- malloc_usable_size(Void_t* p);
-
- Returns the number of bytes you can actually use in
- an allocated chunk, which may be more than you requested (although
- often not) due to alignment and minimum size constraints.
- You can use this many bytes without worrying about
- overwriting other allocated objects. This is not a particularly great
- programming practice. malloc_usable_size can be more useful in
- debugging and assertions, for example:
-
- p = malloc(n);
- assert(malloc_usable_size(p) >= 256);
-
-*/
-#if __STD_C
-size_t public_mUSABLe(Void_t*);
-#else
-size_t public_mUSABLe();
-#endif
-
-/*
- malloc_stats();
- Prints on stderr the amount of space obtained from the system (both
- via sbrk and mmap), the maximum amount (which may be more than
- current if malloc_trim and/or munmap got called), and the current
- number of bytes allocated via malloc (or realloc, etc) but not yet
- freed. Note that this is the number of bytes allocated, not the
- number requested. It will be larger than the number requested
- because of alignment and bookkeeping overhead. Because it includes
- alignment wastage as being in use, this figure may be greater than
- zero even when no user-level chunks are allocated.
-
- The reported current and maximum system memory can be inaccurate if
- a program makes other calls to system memory allocation functions
- (normally sbrk) outside of malloc.
-
- malloc_stats prints only the most commonly interesting statistics.
- More information can be obtained by calling mallinfo.
-
-*/
-#if __STD_C
-void public_mSTATs();
-#else
-void public_mSTATs();
-#endif
-
-/* mallopt tuning options */
-
-/*
- M_MXFAST is the maximum request size used for "fastbins", special bins
- that hold returned chunks without consolidating their spaces. This
- enables future requests for chunks of the same size to be handled
- very quickly, but can increase fragmentation, and thus increase the
- overall memory footprint of a program.
-
- This malloc manages fastbins very conservatively yet still
- efficiently, so fragmentation is rarely a problem for values less
- than or equal to the default. The maximum supported value of MXFAST
- is 80. You wouldn't want it any higher than this anyway. Fastbins
- are designed especially for use with many small structs, objects or
- strings -- the default handles structs/objects/arrays with sizes up
- to 16 4byte fields, or small strings representing words, tokens,
- etc. Using fastbins for larger objects normally worsens
- fragmentation without improving speed.
-
- M_MXFAST is set in REQUEST size units. It is internally used in
- chunksize units, which adds padding and alignment. You can reduce
- M_MXFAST to 0 to disable all use of fastbins. This causes the malloc
- algorithm to be a closer approximation of fifo-best-fit in all cases,
- not just for larger requests, but will generally cause it to be
- slower.
-*/
-
-
-/* M_MXFAST is a standard SVID/XPG tuning option, usually listed in malloc.h */
-#ifndef M_MXFAST
-#define M_MXFAST 1
-#endif
-
-#ifndef DEFAULT_MXFAST
-#define DEFAULT_MXFAST 64
-#endif
-
-
-/*
- M_TRIM_THRESHOLD is the maximum amount of unused top-most memory
- to keep before releasing via malloc_trim in free().
-
- Automatic trimming is mainly useful in long-lived programs.
- Because trimming via sbrk can be slow on some systems, and can
- sometimes be wasteful (in cases where programs immediately
- afterward allocate more large chunks) the value should be high
- enough so that your overall system performance would improve by
- releasing this much memory.
-
- The trim threshold and the mmap control parameters (see below)
- can be traded off with one another. Trimming and mmapping are
- two different ways of releasing unused memory back to the
- system. Between these two, it is often possible to keep
- system-level demands of a long-lived program down to a bare
- minimum. For example, in one test suite of sessions measuring
- the XF86 X server on Linux, using a trim threshold of 128K and a
- mmap threshold of 192K led to near-minimal long term resource
- consumption.
-
- If you are using this malloc in a long-lived program, it should
- pay to experiment with these values. As a rough guide, you
- might set to a value close to the average size of a process
- (program) running on your system. Releasing this much memory
- would allow such a process to run in memory. Generally, it's
- worth it to tune for trimming rather tham memory mapping when a
- program undergoes phases where several large chunks are
- allocated and released in ways that can reuse each other's
- storage, perhaps mixed with phases where there are no such
- chunks at all. And in well-behaved long-lived programs,
- controlling release of large blocks via trimming versus mapping
- is usually faster.
-
- However, in most programs, these parameters serve mainly as
- protection against the system-level effects of carrying around
- massive amounts of unneeded memory. Since frequent calls to
- sbrk, mmap, and munmap otherwise degrade performance, the default
- parameters are set to relatively high values that serve only as
- safeguards.
-
- The trim value must be greater than page size to have any useful
- effect. To disable trimming completely, you can set to
- (unsigned long)(-1)
-
- Trim settings interact with fastbin (MXFAST) settings: Unless
- TRIM_FASTBINS is defined, automatic trimming never takes place upon
- freeing a chunk with size less than or equal to MXFAST. Trimming is
- instead delayed until subsequent freeing of larger chunks. However,
- you can still force an attempted trim by calling malloc_trim.
-
- Also, trimming is not generally possible in cases where
- the main arena is obtained via mmap.
-
- Note that the trick some people use of mallocing a huge space and
- then freeing it at program startup, in an attempt to reserve system
- memory, doesn't have the intended effect under automatic trimming,
- since that memory will immediately be returned to the system.
-*/
-
-#define M_TRIM_THRESHOLD -1
-
-#ifndef DEFAULT_TRIM_THRESHOLD
-#define DEFAULT_TRIM_THRESHOLD (256 * 1024)
-#endif
-
-/*
- M_TOP_PAD is the amount of extra `padding' space to allocate or
- retain whenever sbrk is called. It is used in two ways internally:
-
- * When sbrk is called to extend the top of the arena to satisfy
- a new malloc request, this much padding is added to the sbrk
- request.
-
- * When malloc_trim is called automatically from free(),
- it is used as the `pad' argument.
-
- In both cases, the actual amount of padding is rounded
- so that the end of the arena is always a system page boundary.
-
- The main reason for using padding is to avoid calling sbrk so
- often. Having even a small pad greatly reduces the likelihood
- that nearly every malloc request during program start-up (or
- after trimming) will invoke sbrk, which needlessly wastes
- time.
-
- Automatic rounding-up to page-size units is normally sufficient
- to avoid measurable overhead, so the default is 0. However, in
- systems where sbrk is relatively slow, it can pay to increase
- this value, at the expense of carrying around more memory than
- the program needs.
-*/
-
-#define M_TOP_PAD -2
-
-#ifndef DEFAULT_TOP_PAD
-#define DEFAULT_TOP_PAD (0)
-#endif
-
-/*
- M_MMAP_THRESHOLD is the request size threshold for using mmap()
- to service a request. Requests of at least this size that cannot
- be allocated using already-existing space will be serviced via mmap.
- (If enough normal freed space already exists it is used instead.)
-
- Using mmap segregates relatively large chunks of memory so that
- they can be individually obtained and released from the host
- system. A request serviced through mmap is never reused by any
- other request (at least not directly; the system may just so
- happen to remap successive requests to the same locations).
-
- Segregating space in this way has the benefits that:
-
- 1. Mmapped space can ALWAYS be individually released back
- to the system, which helps keep the system level memory
- demands of a long-lived program low.
- 2. Mapped memory can never become `locked' between
- other chunks, as can happen with normally allocated chunks, which
- means that even trimming via malloc_trim would not release them.
- 3. On some systems with "holes" in address spaces, mmap can obtain
- memory that sbrk cannot.
-
- However, it has the disadvantages that:
-
- 1. The space cannot be reclaimed, consolidated, and then
- used to service later requests, as happens with normal chunks.
- 2. It can lead to more wastage because of mmap page alignment
- requirements
- 3. It causes malloc performance to be more dependent on host
- system memory management support routines which may vary in
- implementation quality and may impose arbitrary
- limitations. Generally, servicing a request via normal
- malloc steps is faster than going through a system's mmap.
-
- The advantages of mmap nearly always outweigh disadvantages for
- "large" chunks, but the value of "large" varies across systems. The
- default is an empirically derived value that works well in most
- systems.
-*/
-
-#define M_MMAP_THRESHOLD -3
-
-#ifndef DEFAULT_MMAP_THRESHOLD
-#define DEFAULT_MMAP_THRESHOLD (256 * 1024)
-#endif
-
-/*
- M_MMAP_MAX is the maximum number of requests to simultaneously
- service using mmap. This parameter exists because
-. Some systems have a limited number of internal tables for
- use by mmap, and using more than a few of them may degrade
- performance.
-
- The default is set to a value that serves only as a safeguard.
- Setting to 0 disables use of mmap for servicing large requests. If
- HAVE_MMAP is not set, the default value is 0, and attempts to set it
- to non-zero values in mallopt will fail.
-*/
-
-#define M_MMAP_MAX -4
-
-#ifndef DEFAULT_MMAP_MAX
-#if HAVE_MMAP
-#define DEFAULT_MMAP_MAX (65536)
-#else
-#define DEFAULT_MMAP_MAX (0)
-#endif
-#endif
-
-#ifdef __cplusplus
-}; /* end of extern "C" */
-#endif
-
-/*
- ========================================================================
- To make a fully customizable malloc.h header file, cut everything
- above this line, put into file malloc.h, edit to suit, and #include it
- on the next line, as well as in programs that use this malloc.
- ========================================================================
-*/
-
-/* #include "malloc.h" */
-
-/* --------------------- public wrappers ---------------------- */
-
-#ifdef USE_PUBLIC_MALLOC_WRAPPERS
-
-/* Declare all routines as internal */
-#if __STD_C
-static Void_t* mALLOc(size_t);
-static void fREe(Void_t*);
-static Void_t* rEALLOc(Void_t*, size_t);
-static Void_t* mEMALIGn(size_t, size_t);
-static Void_t* vALLOc(size_t);
-static Void_t* pVALLOc(size_t);
-static Void_t* cALLOc(size_t, size_t);
-static Void_t** iCALLOc(size_t, size_t, Void_t**);
-static Void_t** iCOMALLOc(size_t, size_t*, Void_t**);
-static void cFREe(Void_t*);
-static int mTRIm(size_t);
-static size_t mUSABLe(Void_t*);
-static void mSTATs();
-static int mALLOPt(int, int);
-static struct mallinfo mALLINFo(void);
-#else
-static Void_t* mALLOc();
-static void fREe();
-static Void_t* rEALLOc();
-static Void_t* mEMALIGn();
-static Void_t* vALLOc();
-static Void_t* pVALLOc();
-static Void_t* cALLOc();
-static Void_t** iCALLOc();
-static Void_t** iCOMALLOc();
-static void cFREe();
-static int mTRIm();
-static size_t mUSABLe();
-static void mSTATs();
-static int mALLOPt();
-static struct mallinfo mALLINFo();
-#endif
-
-/*
- MALLOC_PREACTION and MALLOC_POSTACTION should be
- defined to return 0 on success, and nonzero on failure.
- The return value of MALLOC_POSTACTION is currently ignored
- in wrapper functions since there is no reasonable default
- action to take on failure.
-*/
-
-
-#ifdef USE_MALLOC_LOCK
-
-#ifdef WIN32
-
-static int mALLOC_MUTEx;
-#define MALLOC_PREACTION slwait(&mALLOC_MUTEx)
-#define MALLOC_POSTACTION slrelease(&mALLOC_MUTEx)
-
-#else
-
-#include <pthread.h>
-
-static pthread_mutex_t mALLOC_MUTEx = PTHREAD_MUTEX_INITIALIZER;
-
-#define MALLOC_PREACTION pthread_mutex_lock(&mALLOC_MUTEx)
-#define MALLOC_POSTACTION pthread_mutex_unlock(&mALLOC_MUTEx)
-
-#endif /* USE_MALLOC_LOCK */
-
-#else
-
-/* Substitute anything you like for these */
-
-#define MALLOC_PREACTION (0)
-#define MALLOC_POSTACTION (0)
-
-#endif
-
-Void_t* public_mALLOc(size_t bytes) {
- Void_t* m;
- if (MALLOC_PREACTION != 0) {
- return 0;
- }
- m = mALLOc(bytes);
- if (MALLOC_POSTACTION != 0) {
- }
- return m;
-}
-
-void public_fREe(Void_t* m) {
- if (MALLOC_PREACTION != 0) {
- return;
- }
- fREe(m);
- if (MALLOC_POSTACTION != 0) {
- }
-}
-
-Void_t* public_rEALLOc(Void_t* m, size_t bytes) {
- if (MALLOC_PREACTION != 0) {
- return 0;
- }
- m = rEALLOc(m, bytes);
- if (MALLOC_POSTACTION != 0) {
- }
- return m;
-}
-
-Void_t* public_mEMALIGn(size_t alignment, size_t bytes) {
- Void_t* m;
- if (MALLOC_PREACTION != 0) {
- return 0;
- }
- m = mEMALIGn(alignment, bytes);
- if (MALLOC_POSTACTION != 0) {
- }
- return m;
-}
-
-Void_t* public_vALLOc(size_t bytes) {
- Void_t* m;
- if (MALLOC_PREACTION != 0) {
- return 0;
- }
- m = vALLOc(bytes);
- if (MALLOC_POSTACTION != 0) {
- }
- return m;
-}
-
-#ifdef NEED_PVALLOC
-Void_t* public_pVALLOc(size_t bytes) {
- Void_t* m;
- if (MALLOC_PREACTION != 0) {
- return 0;
- }
- m = pVALLOc(bytes);
- if (MALLOC_POSTACTION != 0) {
- }
- return m;
-}
-#endif
-
-Void_t* public_cALLOc(size_t n, size_t elem_size) {
- Void_t* m;
- if (MALLOC_PREACTION != 0) {
- return 0;
- }
- m = cALLOc(n, elem_size);
- if (MALLOC_POSTACTION != 0) {
- }
- return m;
-}
-
-
-Void_t** public_iCALLOc(size_t n, size_t elem_size, Void_t** chunks) {
- Void_t** m;
- if (MALLOC_PREACTION != 0) {
- return 0;
- }
- m = iCALLOc(n, elem_size, chunks);
- if (MALLOC_POSTACTION != 0) {
- }
- return m;
-}
-
-Void_t** public_iCOMALLOc(size_t n, size_t sizes[], Void_t** chunks) {
- Void_t** m;
- if (MALLOC_PREACTION != 0) {
- return 0;
- }
- m = iCOMALLOc(n, sizes, chunks);
- if (MALLOC_POSTACTION != 0) {
- }
- return m;
-}
-
-void public_cFREe(Void_t* m) {
- if (MALLOC_PREACTION != 0) {
- return;
- }
- cFREe(m);
- if (MALLOC_POSTACTION != 0) {
- }
-}
-
-int public_mTRIm(size_t s) {
- int result;
- if (MALLOC_PREACTION != 0) {
- return 0;
- }
- result = mTRIm(s);
- if (MALLOC_POSTACTION != 0) {
- }
- return result;
-}
-
-size_t public_mUSABLe(Void_t* m) {
- size_t result;
- if (MALLOC_PREACTION != 0) {
- return 0;
- }
- result = mUSABLe(m);
- if (MALLOC_POSTACTION != 0) {
- }
- return result;
-}
-
-void public_mSTATs() {
- if (MALLOC_PREACTION != 0) {
- return;
- }
- mSTATs();
- if (MALLOC_POSTACTION != 0) {
- }
-}
-
-struct mallinfo public_mALLINFo() {
- struct mallinfo m;
- if (MALLOC_PREACTION != 0) {
- struct mallinfo nm = { 0, 0, 0, 0, 0, 0, 0, 0, 0, 0 };
- return nm;
- }
- m = mALLINFo();
- if (MALLOC_POSTACTION != 0) {
- }
- return m;
-}
-
-int public_mALLOPt(int p, int v) {
- int result;
- if (MALLOC_PREACTION != 0) {
- return 0;
- }
- result = mALLOPt(p, v);
- if (MALLOC_POSTACTION != 0) {
- }
- return result;
-}
-
-#endif
-
-
-
-/* ------------- Optional versions of memcopy ---------------- */
-
-
-#if USE_MEMCPY
-
-/*
- Note: memcpy is ONLY invoked with non-overlapping regions,
- so the (usually slower) memmove is not needed.
-*/
-
-#define MALLOC_COPY(dest, src, nbytes) memcpy(dest, src, nbytes)
-#define MALLOC_ZERO(dest, nbytes) memset(dest, 0, nbytes)
-
-#else /* !USE_MEMCPY */
-
-/* Use Duff's device for good zeroing/copying performance. */
-
-#define MALLOC_ZERO(charp, nbytes) \
-do { \
- INTERNAL_SIZE_T* mzp = (INTERNAL_SIZE_T*)(charp); \
- CHUNK_SIZE_T mctmp = (nbytes)/sizeof(INTERNAL_SIZE_T); \
- long mcn; \
- if (mctmp < 8) mcn = 0; else { mcn = (mctmp-1)/8; mctmp %= 8; } \
- switch (mctmp) { \
- case 0: for(;;) { *mzp++ = 0; \
- case 7: *mzp++ = 0; \
- case 6: *mzp++ = 0; \
- case 5: *mzp++ = 0; \
- case 4: *mzp++ = 0; \
- case 3: *mzp++ = 0; \
- case 2: *mzp++ = 0; \
- case 1: *mzp++ = 0; if(mcn <= 0) break; mcn--; } \
- } \
-} while(0)
-
-#define MALLOC_COPY(dest,src,nbytes) \
-do { \
- INTERNAL_SIZE_T* mcsrc = (INTERNAL_SIZE_T*) src; \
- INTERNAL_SIZE_T* mcdst = (INTERNAL_SIZE_T*) dest; \
- CHUNK_SIZE_T mctmp = (nbytes)/sizeof(INTERNAL_SIZE_T); \
- long mcn; \
- if (mctmp < 8) mcn = 0; else { mcn = (mctmp-1)/8; mctmp %= 8; } \
- switch (mctmp) { \
- case 0: for(;;) { *mcdst++ = *mcsrc++; \
- case 7: *mcdst++ = *mcsrc++; \
- case 6: *mcdst++ = *mcsrc++; \
- case 5: *mcdst++ = *mcsrc++; \
- case 4: *mcdst++ = *mcsrc++; \
- case 3: *mcdst++ = *mcsrc++; \
- case 2: *mcdst++ = *mcsrc++; \
- case 1: *mcdst++ = *mcsrc++; if(mcn <= 0) break; mcn--; } \
- } \
-} while(0)
-
-#endif
-
-/* ------------------ MMAP support ------------------ */
-
-
-#if HAVE_MMAP
-
-#ifndef LACKS_FCNTL_H
-#include <fcntl.h>
-#endif
-
-#ifndef LACKS_SYS_MMAN_H
-#include <sys/mman.h>
-#endif
-
-#if !defined(MAP_ANONYMOUS) && defined(MAP_ANON)
-#define MAP_ANONYMOUS MAP_ANON
-#endif
-
-/*
- Nearly all versions of mmap support MAP_ANONYMOUS,
- so the following is unlikely to be needed, but is
- supplied just in case.
-*/
-
-#ifndef MAP_ANONYMOUS
-
-static int dev_zero_fd = -1; /* Cached file descriptor for /dev/zero. */
-
-#define MMAP(addr, size, prot, flags) ((dev_zero_fd < 0) ? \
- (dev_zero_fd = open("/dev/zero", O_RDWR), \
- mmap((addr), (size), (prot), (flags), dev_zero_fd, 0)) : \
- mmap((addr), (size), (prot), (flags), dev_zero_fd, 0))
-
-#else
-
-#define MMAP(addr, size, prot, flags) \
- (mmap((addr), (size), (prot), (flags)|MAP_ANONYMOUS, -1, 0))
-
-#endif
-
-
-#endif /* HAVE_MMAP */
-
-
-/*
- ----------------------- Chunk representations -----------------------
-*/
-
-
-/*
- This struct declaration is misleading (but accurate and necessary).
- It declares a "view" into memory allowing access to necessary
- fields at known offsets from a given base. See explanation below.
-*/
-
-struct malloc_chunk {
-
- INTERNAL_SIZE_T prev_size; /* Size of previous chunk (if free). */
- INTERNAL_SIZE_T size; /* Size in bytes, including overhead. */
-
- struct malloc_chunk* fd; /* double links -- used only if free. */
- struct malloc_chunk* bk;
-};
-
-
-typedef struct malloc_chunk* mchunkptr;
-
-/*
- malloc_chunk details:
-
- (The following includes lightly edited explanations by Colin Plumb.)
-
- Chunks of memory are maintained using a `boundary tag' method as
- described in e.g., Knuth or Standish. (See the paper by Paul
- Wilson ftp://ftp.cs.utexas.edu/pub/garbage/allocsrv.ps for a
- survey of such techniques.) Sizes of free chunks are stored both
- in the front of each chunk and at the end. This makes
- consolidating fragmented chunks into bigger chunks very fast. The
- size fields also hold bits representing whether chunks are free or
- in use.
-
- An allocated chunk looks like this:
-
-
- chunk-> +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
- | Size of previous chunk, if allocated | |
- +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
- | Size of chunk, in bytes |P|
- mem-> +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
- | User data starts here... .
- . .
- . (malloc_usable_space() bytes) .
- . |
-nextchunk-> +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
- | Size of chunk |
- +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
-
-
- Where "chunk" is the front of the chunk for the purpose of most of
- the malloc code, but "mem" is the pointer that is returned to the
- user. "Nextchunk" is the beginning of the next contiguous chunk.
-
- Chunks always begin on even word boundries, so the mem portion
- (which is returned to the user) is also on an even word boundary, and
- thus at least double-word aligned.
-
- Free chunks are stored in circular doubly-linked lists, and look like this:
-
- chunk-> +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
- | Size of previous chunk |
- +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
- `head:' | Size of chunk, in bytes |P|
- mem-> +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
- | Forward pointer to next chunk in list |
- +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
- | Back pointer to previous chunk in list |
- +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
- | Unused space (may be 0 bytes long) .
- . .
- . |
-nextchunk-> +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
- `foot:' | Size of chunk, in bytes |
- +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
-
- The P (PREV_INUSE) bit, stored in the unused low-order bit of the
- chunk size (which is always a multiple of two words), is an in-use
- bit for the *previous* chunk. If that bit is *clear*, then the
- word before the current chunk size contains the previous chunk
- size, and can be used to find the front of the previous chunk.
- The very first chunk allocated always has this bit set,
- preventing access to non-existent (or non-owned) memory. If
- prev_inuse is set for any given chunk, then you CANNOT determine
- the size of the previous chunk, and might even get a memory
- addressing fault when trying to do so.
-
- Note that the `foot' of the current chunk is actually represented
- as the prev_size of the NEXT chunk. This makes it easier to
- deal with alignments etc but can be very confusing when trying
- to extend or adapt this code.
-
- The two exceptions to all this are
-
- 1. The special chunk `top' doesn't bother using the
- trailing size field since there is no next contiguous chunk
- that would have to index off it. After initialization, `top'
- is forced to always exist. If it would become less than
- MINSIZE bytes long, it is replenished.
-
- 2. Chunks allocated via mmap, which have the second-lowest-order
- bit (IS_MMAPPED) set in their size fields. Because they are
- allocated one-by-one, each must contain its own trailing size field.
-
-*/
-
-/*
- ---------- Size and alignment checks and conversions ----------
-*/
-
-/* conversion from malloc headers to user pointers, and back */
-
-#define chunk2mem(p) ((Void_t*)((char*)(p) + 2*SIZE_SZ))
-#define mem2chunk(mem) ((mchunkptr)((char*)(mem) - 2*SIZE_SZ))
-
-/* The smallest possible chunk */
-#define MIN_CHUNK_SIZE (sizeof(struct malloc_chunk))
-
-/* The smallest size we can malloc is an aligned minimal chunk */
-
-#define MINSIZE \
- (CHUNK_SIZE_T)(((MIN_CHUNK_SIZE+MALLOC_ALIGN_MASK) & ~MALLOC_ALIGN_MASK))
-
-/* Check if m has acceptable alignment */
-
-#define aligned_OK(m) (((PTR_UINT)((m)) & (MALLOC_ALIGN_MASK)) == 0)
-
-
-/*
- Check if a request is so large that it would wrap around zero when
- padded and aligned. To simplify some other code, the bound is made
- low enough so that adding MINSIZE will also not wrap around sero.
-*/
-
-#define REQUEST_OUT_OF_RANGE(req) \
- ((CHUNK_SIZE_T)(req) >= \
- (CHUNK_SIZE_T)(INTERNAL_SIZE_T)(-2 * MINSIZE))
-
-/* pad request bytes into a usable size -- internal version */
-
-#define request2size(req) \
- (((req) + SIZE_SZ + MALLOC_ALIGN_MASK < MINSIZE) ? \
- MINSIZE : \
- ((req) + SIZE_SZ + MALLOC_ALIGN_MASK) & ~MALLOC_ALIGN_MASK)
-
-/* Same, except also perform argument check */
-
-#define checked_request2size(req, sz) \
- if (REQUEST_OUT_OF_RANGE(req)) { \
- MALLOC_FAILURE_ACTION; \
- return 0; \
- } \
- (sz) = request2size(req);
-
-/*
- --------------- Physical chunk operations ---------------
-*/
-
-
-/* size field is or'ed with PREV_INUSE when previous adjacent chunk in use */
-#define PREV_INUSE 0x1
-
-/* extract inuse bit of previous chunk */
-#define prev_inuse(p) ((p)->size & PREV_INUSE)
-
-
-/* size field is or'ed with IS_MMAPPED if the chunk was obtained with mmap() */
-#define IS_MMAPPED 0x2
-
-/* check for mmap()'ed chunk */
-#define chunk_is_mmapped(p) ((p)->size & IS_MMAPPED)
-
-/*
- Bits to mask off when extracting size
-
- Note: IS_MMAPPED is intentionally not masked off from size field in
- macros for which mmapped chunks should never be seen. This should
- cause helpful core dumps to occur if it is tried by accident by
- people extending or adapting this malloc.
-*/
-#define SIZE_BITS (PREV_INUSE|IS_MMAPPED)
-
-/* Get size, ignoring use bits */
-#define chunksize(p) ((p)->size & ~(SIZE_BITS))
-
-
-/* Ptr to next physical malloc_chunk. */
-#define next_chunk(p) ((mchunkptr)( ((char*)(p)) + ((p)->size & ~PREV_INUSE) ))
-
-/* Ptr to previous physical malloc_chunk */
-#define prev_chunk(p) ((mchunkptr)( ((char*)(p)) - ((p)->prev_size) ))
-
-/* Treat space at ptr + offset as a chunk */
-#define chunk_at_offset(p, s) ((mchunkptr)(((char*)(p)) + (s)))
-
-/* extract p's inuse bit */
-#define inuse(p)\
-((((mchunkptr)(((char*)(p))+((p)->size & ~PREV_INUSE)))->size) & PREV_INUSE)
-
-/* set/clear chunk as being inuse without otherwise disturbing */
-#define set_inuse(p)\
-((mchunkptr)(((char*)(p)) + ((p)->size & ~PREV_INUSE)))->size |= PREV_INUSE
-
-#define clear_inuse(p)\
-((mchunkptr)(((char*)(p)) + ((p)->size & ~PREV_INUSE)))->size &= ~(PREV_INUSE)
-
-
-/* check/set/clear inuse bits in known places */
-#define inuse_bit_at_offset(p, s)\
- (((mchunkptr)(((char*)(p)) + (s)))->size & PREV_INUSE)
-
-#define set_inuse_bit_at_offset(p, s)\
- (((mchunkptr)(((char*)(p)) + (s)))->size |= PREV_INUSE)
-
-#define clear_inuse_bit_at_offset(p, s)\
- (((mchunkptr)(((char*)(p)) + (s)))->size &= ~(PREV_INUSE))
-
-
-/* Set size at head, without disturbing its use bit */
-#define set_head_size(p, s) ((p)->size = (((p)->size & PREV_INUSE) | (s)))
-
-/* Set size/use field */
-#define set_head(p, s) ((p)->size = (s))
-
-/* Set size at footer (only when chunk is not in use) */
-#define set_foot(p, s) (((mchunkptr)((char*)(p) + (s)))->prev_size = (s))
-
-
-/*
- -------------------- Internal data structures --------------------
-
- All internal state is held in an instance of malloc_state defined
- below. There are no other static variables, except in two optional
- cases:
- * If USE_MALLOC_LOCK is defined, the mALLOC_MUTEx declared above.
- * If HAVE_MMAP is true, but mmap doesn't support
- MAP_ANONYMOUS, a dummy file descriptor for mmap.
-
- Beware of lots of tricks that minimize the total bookkeeping space
- requirements. The result is a little over 1K bytes (for 4byte
- pointers and size_t.)
-*/
-
-/*
- Bins
-
- An array of bin headers for free chunks. Each bin is doubly
- linked. The bins are approximately proportionally (log) spaced.
- There are a lot of these bins (128). This may look excessive, but
- works very well in practice. Most bins hold sizes that are
- unusual as malloc request sizes, but are more usual for fragments
- and consolidated sets of chunks, which is what these bins hold, so
- they can be found quickly. All procedures maintain the invariant
- that no consolidated chunk physically borders another one, so each
- chunk in a list is known to be preceeded and followed by either
- inuse chunks or the ends of memory.
-
- Chunks in bins are kept in size order, with ties going to the
- approximately least recently used chunk. Ordering isn't needed
- for the small bins, which all contain the same-sized chunks, but
- facilitates best-fit allocation for larger chunks. These lists
- are just sequential. Keeping them in order almost never requires
- enough traversal to warrant using fancier ordered data
- structures.
-
- Chunks of the same size are linked with the most
- recently freed at the front, and allocations are taken from the
- back. This results in LRU (FIFO) allocation order, which tends
- to give each chunk an equal opportunity to be consolidated with
- adjacent freed chunks, resulting in larger free chunks and less
- fragmentation.
-
- To simplify use in double-linked lists, each bin header acts
- as a malloc_chunk. This avoids special-casing for headers.
- But to conserve space and improve locality, we allocate
- only the fd/bk pointers of bins, and then use repositioning tricks
- to treat these as the fields of a malloc_chunk*.
-*/
-
-typedef struct malloc_chunk* mbinptr;
-
-/* addressing -- note that bin_at(0) does not exist */
-#define bin_at(m, i) ((mbinptr)((char*)&((m)->bins[(i)<<1]) - (SIZE_SZ<<1)))
-
-/* analog of ++bin */
-#define next_bin(b) ((mbinptr)((char*)(b) + (sizeof(mchunkptr)<<1)))
-
-/* Reminders about list directionality within bins */
-#define first(b) ((b)->fd)
-#define last(b) ((b)->bk)
-
-/* Take a chunk off a bin list */
-#define unlink(P, BK, FD) { \
- FD = P->fd; \
- BK = P->bk; \
- FD->bk = BK; \
- BK->fd = FD; \
-}
-
-/*
- Indexing
-
- Bins for sizes < 512 bytes contain chunks of all the same size, spaced
- 8 bytes apart. Larger bins are approximately logarithmically spaced:
-
- 64 bins of size 8
- 32 bins of size 64
- 16 bins of size 512
- 8 bins of size 4096
- 4 bins of size 32768
- 2 bins of size 262144
- 1 bin of size what's left
-
- The bins top out around 1MB because we expect to service large
- requests via mmap.
-*/
-
-#define NBINS 96
-#define NSMALLBINS 32
-#define SMALLBIN_WIDTH 8
-#define MIN_LARGE_SIZE 256
-
-#define in_smallbin_range(sz) \
- ((CHUNK_SIZE_T)(sz) < (CHUNK_SIZE_T)MIN_LARGE_SIZE)
-
-#define smallbin_index(sz) (((unsigned)(sz)) >> 3)
-
-/*
- Compute index for size. We expect this to be inlined when
- compiled with optimization, else not, which works out well.
-*/
-static int largebin_index(unsigned int sz) {
- unsigned int x = sz >> SMALLBIN_WIDTH;
- unsigned int m; /* bit position of highest set bit of m */
-
- if (x >= 0x10000) return NBINS-1;
-
- /* On intel, use BSRL instruction to find highest bit */
-#if defined(__GNUC__) && defined(i386)
-
- __asm__("bsrl %1,%0\n\t"
- : "=r" (m)
- : "g" (x));
-
-#else
- {
- /*
- Based on branch-free nlz algorithm in chapter 5 of Henry
- S. Warren Jr's book "Hacker's Delight".
- */
-
- unsigned int n = ((x - 0x100) >> 16) & 8;
- x <<= n;
- m = ((x - 0x1000) >> 16) & 4;
- n += m;
- x <<= m;
- m = ((x - 0x4000) >> 16) & 2;
- n += m;
- x = (x << m) >> 14;
- m = 13 - n + (x & ~(x>>1));
- }
-#endif
-
- /* Use next 2 bits to create finer-granularity bins */
- return NSMALLBINS + (m << 2) + ((sz >> (m + 6)) & 3);
-}
-
-#define bin_index(sz) \
- ((in_smallbin_range(sz)) ? smallbin_index(sz) : largebin_index(sz))
-
-/*
- FIRST_SORTED_BIN_SIZE is the chunk size corresponding to the
- first bin that is maintained in sorted order. This must
- be the smallest size corresponding to a given bin.
-
- Normally, this should be MIN_LARGE_SIZE. But you can weaken
- best fit guarantees to sometimes speed up malloc by increasing value.
- Doing this means that malloc may choose a chunk that is
- non-best-fitting by up to the width of the bin.
-
- Some useful cutoff values:
- 512 - all bins sorted
- 2560 - leaves bins <= 64 bytes wide unsorted
- 12288 - leaves bins <= 512 bytes wide unsorted
- 65536 - leaves bins <= 4096 bytes wide unsorted
- 262144 - leaves bins <= 32768 bytes wide unsorted
- -1 - no bins sorted (not recommended!)
-*/
-
-#define FIRST_SORTED_BIN_SIZE MIN_LARGE_SIZE
-/* #define FIRST_SORTED_BIN_SIZE 65536 */
-
-/*
- Unsorted chunks
-
- All remainders from chunk splits, as well as all returned chunks,
- are first placed in the "unsorted" bin. They are then placed
- in regular bins after malloc gives them ONE chance to be used before
- binning. So, basically, the unsorted_chunks list acts as a queue,
- with chunks being placed on it in free (and malloc_consolidate),
- and taken off (to be either used or placed in bins) in malloc.
-*/
-
-/* The otherwise unindexable 1-bin is used to hold unsorted chunks. */
-#define unsorted_chunks(M) (bin_at(M, 1))
-
-/*
- Top
-
- The top-most available chunk (i.e., the one bordering the end of
- available memory) is treated specially. It is never included in
- any bin, is used only if no other chunk is available, and is
- released back to the system if it is very large (see
- M_TRIM_THRESHOLD). Because top initially
- points to its own bin with initial zero size, thus forcing
- extension on the first malloc request, we avoid having any special
- code in malloc to check whether it even exists yet. But we still
- need to do so when getting memory from system, so we make
- initial_top treat the bin as a legal but unusable chunk during the
- interval between initialization and the first call to
- sYSMALLOc. (This is somewhat delicate, since it relies on
- the 2 preceding words to be zero during this interval as well.)
-*/
-
-/* Conveniently, the unsorted bin can be used as dummy top on first call */
-#define initial_top(M) (unsorted_chunks(M))
-
-/*
- Binmap
-
- To help compensate for the large number of bins, a one-level index
- structure is used for bin-by-bin searching. `binmap' is a
- bitvector recording whether bins are definitely empty so they can
- be skipped over during during traversals. The bits are NOT always
- cleared as soon as bins are empty, but instead only
- when they are noticed to be empty during traversal in malloc.
-*/
-
-/* Conservatively use 32 bits per map word, even if on 64bit system */
-#define BINMAPSHIFT 5
-#define BITSPERMAP (1U << BINMAPSHIFT)
-#define BINMAPSIZE (NBINS / BITSPERMAP)
-
-#define idx2block(i) ((i) >> BINMAPSHIFT)
-#define idx2bit(i) ((1U << ((i) & ((1U << BINMAPSHIFT)-1))))
-
-#define mark_bin(m,i) ((m)->binmap[idx2block(i)] |= idx2bit(i))
-#define unmark_bin(m,i) ((m)->binmap[idx2block(i)] &= ~(idx2bit(i)))
-#define get_binmap(m,i) ((m)->binmap[idx2block(i)] & idx2bit(i))
-
-/*
- Fastbins
-
- An array of lists holding recently freed small chunks. Fastbins
- are not doubly linked. It is faster to single-link them, and
- since chunks are never removed from the middles of these lists,
- double linking is not necessary. Also, unlike regular bins, they
- are not even processed in FIFO order (they use faster LIFO) since
- ordering doesn't much matter in the transient contexts in which
- fastbins are normally used.
-
- Chunks in fastbins keep their inuse bit set, so they cannot
- be consolidated with other free chunks. malloc_consolidate
- releases all chunks in fastbins and consolidates them with
- other free chunks.
-*/
-
-typedef struct malloc_chunk* mfastbinptr;
-
-/* offset 2 to use otherwise unindexable first 2 bins */
-#define fastbin_index(sz) ((((unsigned int)(sz)) >> 3) - 2)
-
-/* The maximum fastbin request size we support */
-#define MAX_FAST_SIZE 80
-
-#define NFASTBINS (fastbin_index(request2size(MAX_FAST_SIZE))+1)
-
-/*
- FASTBIN_CONSOLIDATION_THRESHOLD is the size of a chunk in free()
- that triggers automatic consolidation of possibly-surrounding
- fastbin chunks. This is a heuristic, so the exact value should not
- matter too much. It is defined at half the default trim threshold as a
- compromise heuristic to only attempt consolidation if it is likely
- to lead to trimming. However, it is not dynamically tunable, since
- consolidation reduces fragmentation surrounding loarge chunks even
- if trimming is not used.
-*/
-
-#define FASTBIN_CONSOLIDATION_THRESHOLD \
- ((unsigned long)(DEFAULT_TRIM_THRESHOLD) >> 1)
-
-/*
- Since the lowest 2 bits in max_fast don't matter in size comparisons,
- they are used as flags.
-*/
-
-/*
- ANYCHUNKS_BIT held in max_fast indicates that there may be any
- freed chunks at all. It is set true when entering a chunk into any
- bin.
-*/
-
-#define ANYCHUNKS_BIT (1U)
-
-#define have_anychunks(M) (((M)->max_fast & ANYCHUNKS_BIT))
-#define set_anychunks(M) ((M)->max_fast |= ANYCHUNKS_BIT)
-#define clear_anychunks(M) ((M)->max_fast &= ~ANYCHUNKS_BIT)
-
-/*
- FASTCHUNKS_BIT held in max_fast indicates that there are probably
- some fastbin chunks. It is set true on entering a chunk into any
- fastbin, and cleared only in malloc_consolidate.
-*/
-
-#define FASTCHUNKS_BIT (2U)
-
-#define have_fastchunks(M) (((M)->max_fast & FASTCHUNKS_BIT))
-#define set_fastchunks(M) ((M)->max_fast |= (FASTCHUNKS_BIT|ANYCHUNKS_BIT))
-#define clear_fastchunks(M) ((M)->max_fast &= ~(FASTCHUNKS_BIT))
-
-/*
- Set value of max_fast.
- Use impossibly small value if 0.
-*/
-
-#define set_max_fast(M, s) \
- (M)->max_fast = (((s) == 0)? SMALLBIN_WIDTH: request2size(s)) | \
- ((M)->max_fast & (FASTCHUNKS_BIT|ANYCHUNKS_BIT))
-
-#define get_max_fast(M) \
- ((M)->max_fast & ~(FASTCHUNKS_BIT | ANYCHUNKS_BIT))
-
-
-/*
- morecore_properties is a status word holding dynamically discovered
- or controlled properties of the morecore function
-*/
-
-#define MORECORE_CONTIGUOUS_BIT (1U)
-
-#define contiguous(M) \
- (((M)->morecore_properties & MORECORE_CONTIGUOUS_BIT))
-#define noncontiguous(M) \
- (((M)->morecore_properties & MORECORE_CONTIGUOUS_BIT) == 0)
-#define set_contiguous(M) \
- ((M)->morecore_properties |= MORECORE_CONTIGUOUS_BIT)
-#define set_noncontiguous(M) \
- ((M)->morecore_properties &= ~MORECORE_CONTIGUOUS_BIT)
-
-
-/*
- ----------- Internal state representation and initialization -----------
-*/
-
-struct malloc_state {
-
- /* The maximum chunk size to be eligible for fastbin */
- INTERNAL_SIZE_T max_fast; /* low 2 bits used as flags */
-
- /* Fastbins */
- mfastbinptr fastbins[NFASTBINS];
-
- /* Base of the topmost chunk -- not otherwise kept in a bin */
- mchunkptr top;
-
- /* The remainder from the most recent split of a small request */
- mchunkptr last_remainder;
-
- /* Normal bins packed as described above */
- mchunkptr bins[NBINS * 2];
-
- /* Bitmap of bins. Trailing zero map handles cases of largest binned size */
- unsigned int binmap[BINMAPSIZE+1];
-
- /* Tunable parameters */
- CHUNK_SIZE_T trim_threshold;
- INTERNAL_SIZE_T top_pad;
- INTERNAL_SIZE_T mmap_threshold;
-
- /* Memory map support */
- int n_mmaps;
- int n_mmaps_max;
- int max_n_mmaps;
-
- /* Cache malloc_getpagesize */
- unsigned int pagesize;
-
- /* Track properties of MORECORE */
- unsigned int morecore_properties;
-
- /* Statistics */
- INTERNAL_SIZE_T mmapped_mem;
- INTERNAL_SIZE_T sbrked_mem;
- INTERNAL_SIZE_T max_sbrked_mem;
- INTERNAL_SIZE_T max_mmapped_mem;
- INTERNAL_SIZE_T max_total_mem;
-};
-
-typedef struct malloc_state *mstate;
-
-/*
- There is exactly one instance of this struct in this malloc.
- If you are adapting this malloc in a way that does NOT use a static
- malloc_state, you MUST explicitly zero-fill it before using. This
- malloc relies on the property that malloc_state is initialized to
- all zeroes (as is true of C statics).
-*/
-
-static struct malloc_state av_; /* never directly referenced */
-
-/*
- All uses of av_ are via get_malloc_state().
- At most one "call" to get_malloc_state is made per invocation of
- the public versions of malloc and free, but other routines
- that in turn invoke malloc and/or free may call more then once.
- Also, it is called in check* routines if DEBUG is set.
-*/
-
-#define get_malloc_state() (&(av_))
-
-/*
- Initialize a malloc_state struct.
-
- This is called only from within malloc_consolidate, which needs
- be called in the same contexts anyway. It is never called directly
- outside of malloc_consolidate because some optimizing compilers try
- to inline it at all call points, which turns out not to be an
- optimization at all. (Inlining it in malloc_consolidate is fine though.)
-*/
-
-#if __STD_C
-static void malloc_init_state(mstate av)
-#else
-static void malloc_init_state(av) mstate av;
-#endif
-{
- int i;
- mbinptr bin;
-
- /* Establish circular links for normal bins */
- for (i = 1; i < NBINS; ++i) {
- bin = bin_at(av,i);
- bin->fd = bin->bk = bin;
- }
-
- av->top_pad = DEFAULT_TOP_PAD;
- av->n_mmaps_max = DEFAULT_MMAP_MAX;
- av->mmap_threshold = DEFAULT_MMAP_THRESHOLD;
- av->trim_threshold = DEFAULT_TRIM_THRESHOLD;
-
-#if MORECORE_CONTIGUOUS
- set_contiguous(av);
-#else
- set_noncontiguous(av);
-#endif
-
-
- set_max_fast(av, DEFAULT_MXFAST);
-
- av->top = initial_top(av);
- av->pagesize = malloc_getpagesize;
-}
-
-/*
- Other internal utilities operating on mstates
-*/
-
-#if __STD_C
-static Void_t* sYSMALLOc(INTERNAL_SIZE_T, mstate);
-#ifndef MORECORE_CANNOT_TRIM
-static int sYSTRIm(size_t, mstate);
-#endif
-static void malloc_consolidate(mstate);
-#ifdef NEED_INDEPENDENT
-static Void_t** iALLOc(size_t, size_t*, int, Void_t**);
-#endif
-#else
-static Void_t* sYSMALLOc();
-#ifndef MORECORE_CANNOT_TRIM
-static int sYSTRIm();
-#endif
-static void malloc_consolidate();
-#ifdef NEED_INDEPENDENT
-static Void_t** iALLOc();
-#endif
-#endif
-
-/*
- Debugging support
-
- These routines make a number of assertions about the states
- of data structures that should be true at all times. If any
- are not true, it's very likely that a user program has somehow
- trashed memory. (It's also possible that there is a coding error
- in malloc. In which case, please report it!)
-*/
-
-#if ! DEBUG
-
-#define check_chunk(P)
-#define check_free_chunk(P)
-#define check_inuse_chunk(P)
-#define check_remalloced_chunk(P,N)
-#define check_malloced_chunk(P,N)
-#define check_malloc_state()
-
-#else
-#define check_chunk(P) do_check_chunk(P)
-#define check_free_chunk(P) do_check_free_chunk(P)
-#define check_inuse_chunk(P) do_check_inuse_chunk(P)
-#define check_remalloced_chunk(P,N) do_check_remalloced_chunk(P,N)
-#define check_malloced_chunk(P,N) do_check_malloced_chunk(P,N)
-#define check_malloc_state() do_check_malloc_state()
-
-/*
- Properties of all chunks
-*/
-
-#if __STD_C
-static void do_check_chunk(mchunkptr p)
-#else
-static void do_check_chunk(p) mchunkptr p;
-#endif
-{
- mstate av = get_malloc_state();
- CHUNK_SIZE_T sz = chunksize(p);
- /* min and max possible addresses assuming contiguous allocation */
- char* max_address = (char*)(av->top) + chunksize(av->top);
- char* min_address = max_address - av->sbrked_mem;
-
- if (!chunk_is_mmapped(p)) {
-
- /* Has legal address ... */
- if (p != av->top) {
- if (contiguous(av)) {
- assert(((char*)p) >= min_address);
- assert(((char*)p + sz) <= ((char*)(av->top)));
- }
- }
- else {
- /* top size is always at least MINSIZE */
- assert((CHUNK_SIZE_T)(sz) >= MINSIZE);
- /* top predecessor always marked inuse */
- assert(prev_inuse(p));
- }
-
- }
- else {
-#if HAVE_MMAP
- /* address is outside main heap */
- if (contiguous(av) && av->top != initial_top(av)) {
- assert(((char*)p) < min_address || ((char*)p) > max_address);
- }
- /* chunk is page-aligned */
- assert(((p->prev_size + sz) & (av->pagesize-1)) == 0);
- /* mem is aligned */
- assert(aligned_OK(chunk2mem(p)));
-#else
- /* force an appropriate assert violation if debug set */
- assert(!chunk_is_mmapped(p));
-#endif
- }
-}
-
-/*
- Properties of free chunks
-*/
-
-#if __STD_C
-static void do_check_free_chunk(mchunkptr p)
-#else
-static void do_check_free_chunk(p) mchunkptr p;
-#endif
-{
- mstate av = get_malloc_state();
-
- INTERNAL_SIZE_T sz = p->size & ~PREV_INUSE;
- mchunkptr next = chunk_at_offset(p, sz);
-
- do_check_chunk(p);
-
- /* Chunk must claim to be free ... */
- assert(!inuse(p));
- assert (!chunk_is_mmapped(p));
-
- /* Unless a special marker, must have OK fields */
- if ((CHUNK_SIZE_T)(sz) >= MINSIZE)
- {
- assert((sz & MALLOC_ALIGN_MASK) == 0);
- assert(aligned_OK(chunk2mem(p)));
- /* ... matching footer field */
- assert(next->prev_size == sz);
- /* ... and is fully consolidated */
- assert(prev_inuse(p));
- assert (next == av->top || inuse(next));
-
- /* ... and has minimally sane links */
- assert(p->fd->bk == p);
- assert(p->bk->fd == p);
- }
- else /* markers are always of size SIZE_SZ */
- assert(sz == SIZE_SZ);
-}
-
-/*
- Properties of inuse chunks
-*/
-
-#if __STD_C
-static void do_check_inuse_chunk(mchunkptr p)
-#else
-static void do_check_inuse_chunk(p) mchunkptr p;
-#endif
-{
- mstate av = get_malloc_state();
- mchunkptr next;
- do_check_chunk(p);
-
- if (chunk_is_mmapped(p))
- return; /* mmapped chunks have no next/prev */
-
- /* Check whether it claims to be in use ... */
- assert(inuse(p));
-
- next = next_chunk(p);
-
- /* ... and is surrounded by OK chunks.
- Since more things can be checked with free chunks than inuse ones,
- if an inuse chunk borders them and debug is on, it's worth doing them.
- */
- if (!prev_inuse(p)) {
- /* Note that we cannot even look at prev unless it is not inuse */
- mchunkptr prv = prev_chunk(p);
- assert(next_chunk(prv) == p);
- do_check_free_chunk(prv);
- }
-
- if (next == av->top) {
- assert(prev_inuse(next));
- assert(chunksize(next) >= MINSIZE);
- }
- else if (!inuse(next))
- do_check_free_chunk(next);
-}
-
-/*
- Properties of chunks recycled from fastbins
-*/
-
-#if __STD_C
-static void do_check_remalloced_chunk(mchunkptr p, INTERNAL_SIZE_T s)
-#else
-static void do_check_remalloced_chunk(p, s) mchunkptr p; INTERNAL_SIZE_T s;
-#endif
-{
- INTERNAL_SIZE_T sz = p->size & ~PREV_INUSE;
-
- do_check_inuse_chunk(p);
-
- /* Legal size ... */
- assert((sz & MALLOC_ALIGN_MASK) == 0);
- assert((CHUNK_SIZE_T)(sz) >= MINSIZE);
- /* ... and alignment */
- assert(aligned_OK(chunk2mem(p)));
- /* chunk is less than MINSIZE more than request */
- assert((long)(sz) - (long)(s) >= 0);
- assert((long)(sz) - (long)(s + MINSIZE) < 0);
-}
-
-/*
- Properties of nonrecycled chunks at the point they are malloced
-*/
-
-#if __STD_C
-static void do_check_malloced_chunk(mchunkptr p, INTERNAL_SIZE_T s)
-#else
-static void do_check_malloced_chunk(p, s) mchunkptr p; INTERNAL_SIZE_T s;
-#endif
-{
- /* same as recycled case ... */
- do_check_remalloced_chunk(p, s);
-
- /*
- ... plus, must obey implementation invariant that prev_inuse is
- always true of any allocated chunk; i.e., that each allocated
- chunk borders either a previously allocated and still in-use
- chunk, or the base of its memory arena. This is ensured
- by making all allocations from the the `lowest' part of any found
- chunk. This does not necessarily hold however for chunks
- recycled via fastbins.
- */
-
- assert(prev_inuse(p));
-}
-
-
-/*
- Properties of malloc_state.
-
- This may be useful for debugging malloc, as well as detecting user
- programmer errors that somehow write into malloc_state.
-
- If you are extending or experimenting with this malloc, you can
- probably figure out how to hack this routine to print out or
- display chunk addresses, sizes, bins, and other instrumentation.
-*/
-
-static void do_check_malloc_state()
-{
- mstate av = get_malloc_state();
- int i;
- mchunkptr p;
- mchunkptr q;
- mbinptr b;
- unsigned int binbit;
- int empty;
- unsigned int idx;
- INTERNAL_SIZE_T size;
- CHUNK_SIZE_T total = 0;
- int max_fast_bin;
-
- /* internal size_t must be no wider than pointer type */
- assert(sizeof(INTERNAL_SIZE_T) <= sizeof(char*));
-
- /* alignment is a power of 2 */
- assert((MALLOC_ALIGNMENT & (MALLOC_ALIGNMENT-1)) == 0);
-
- /* cannot run remaining checks until fully initialized */
- if (av->top == 0 || av->top == initial_top(av))
- return;
-
- /* pagesize is a power of 2 */
- assert((av->pagesize & (av->pagesize-1)) == 0);
-
- /* properties of fastbins */
-
- /* max_fast is in allowed range */
- assert(get_max_fast(av) <= request2size(MAX_FAST_SIZE));
-
- max_fast_bin = fastbin_index(av->max_fast);
-
- for (i = 0; i < NFASTBINS; ++i) {
- p = av->fastbins[i];
-
- /* all bins past max_fast are empty */
- if (i > max_fast_bin)
- assert(p == 0);
-
- while (p != 0) {
- /* each chunk claims to be inuse */
- do_check_inuse_chunk(p);
- total += chunksize(p);
- /* chunk belongs in this bin */
- assert(fastbin_index(chunksize(p)) == i);
- p = p->fd;
- }
- }
-
- if (total != 0)
- assert(have_fastchunks(av));
- else if (!have_fastchunks(av))
- assert(total == 0);
-
- /* check normal bins */
- for (i = 1; i < NBINS; ++i) {
- b = bin_at(av,i);
-
- /* binmap is accurate (except for bin 1 == unsorted_chunks) */
- if (i >= 2) {
- binbit = get_binmap(av,i);
- empty = last(b) == b;
- if (!binbit)
- assert(empty);
- else if (!empty)
- assert(binbit);
- }
-
- for (p = last(b); p != b; p = p->bk) {
- /* each chunk claims to be free */
- do_check_free_chunk(p);
- size = chunksize(p);
- total += size;
- if (i >= 2) {
- /* chunk belongs in bin */
- idx = bin_index(size);
- assert(idx == i);
- /* lists are sorted */
- if ((CHUNK_SIZE_T) size >= (CHUNK_SIZE_T)(FIRST_SORTED_BIN_SIZE)) {
- assert(p->bk == b ||
- (CHUNK_SIZE_T)chunksize(p->bk) >=
- (CHUNK_SIZE_T)chunksize(p));
- }
- }
- /* chunk is followed by a legal chain of inuse chunks */
- for (q = next_chunk(p);
- (q != av->top && inuse(q) &&
- (CHUNK_SIZE_T)(chunksize(q)) >= MINSIZE);
- q = next_chunk(q))
- do_check_inuse_chunk(q);
- }
- }
-
- /* top chunk is OK */
- check_chunk(av->top);
-
- /* sanity checks for statistics */
-
- assert(total <= (CHUNK_SIZE_T)(av->max_total_mem));
- assert(av->n_mmaps >= 0);
- assert(av->n_mmaps <= av->max_n_mmaps);
-
- assert((CHUNK_SIZE_T)(av->sbrked_mem) <=
- (CHUNK_SIZE_T)(av->max_sbrked_mem));
-
- assert((CHUNK_SIZE_T)(av->mmapped_mem) <=
- (CHUNK_SIZE_T)(av->max_mmapped_mem));
-
- assert((CHUNK_SIZE_T)(av->max_total_mem) >=
- (CHUNK_SIZE_T)(av->mmapped_mem) + (CHUNK_SIZE_T)(av->sbrked_mem));
-}
-#endif
-
-
-/* ----------- Routines dealing with system allocation -------------- */
-
-/*
- sysmalloc handles malloc cases requiring more memory from the system.
- On entry, it is assumed that av->top does not have enough
- space to service request for nb bytes, thus requiring that av->top
- be extended or replaced.
-*/
-
-#if __STD_C
-static Void_t* sYSMALLOc(INTERNAL_SIZE_T nb, mstate av)
-#else
-static Void_t* sYSMALLOc(nb, av) INTERNAL_SIZE_T nb; mstate av;
-#endif
-{
- mchunkptr old_top; /* incoming value of av->top */
- INTERNAL_SIZE_T old_size; /* its size */
- char* old_end; /* its end address */
-
- long size; /* arg to first MORECORE or mmap call */
- char* brk; /* return value from MORECORE */
-
- long correction; /* arg to 2nd MORECORE call */
- char* snd_brk; /* 2nd return val */
-
- INTERNAL_SIZE_T front_misalign; /* unusable bytes at front of new space */
- INTERNAL_SIZE_T end_misalign; /* partial page left at end of new space */
- char* aligned_brk; /* aligned offset into brk */
-
- mchunkptr p; /* the allocated/returned chunk */
- mchunkptr remainder; /* remainder from allocation */
- CHUNK_SIZE_T remainder_size; /* its size */
-
- CHUNK_SIZE_T sum; /* for updating stats */
-
- size_t pagemask = av->pagesize - 1;
-
- /*
- If there is space available in fastbins, consolidate and retry
- malloc from scratch rather than getting memory from system. This
- can occur only if nb is in smallbin range so we didn't consolidate
- upon entry to malloc. It is much easier to handle this case here
- than in malloc proper.
- */
-
- if (have_fastchunks(av)) {
- assert(in_smallbin_range(nb));
- malloc_consolidate(av);
- return mALLOc(nb - MALLOC_ALIGN_MASK);
- }
-
-
-#if HAVE_MMAP
-
- /*
- If have mmap, and the request size meets the mmap threshold, and
- the system supports mmap, and there are few enough currently
- allocated mmapped regions, try to directly map this request
- rather than expanding top.
- */
-
- if ((CHUNK_SIZE_T)(nb) >= (CHUNK_SIZE_T)(av->mmap_threshold) &&
- (av->n_mmaps < av->n_mmaps_max)) {
-
- char* mm; /* return value from mmap call*/
-
- /*
- Round up size to nearest page. For mmapped chunks, the overhead
- is one SIZE_SZ unit larger than for normal chunks, because there
- is no following chunk whose prev_size field could be used.
- */
- size = (nb + SIZE_SZ + MALLOC_ALIGN_MASK + pagemask) & ~pagemask;
-
- /* Don't try if size wraps around 0 */
- if ((CHUNK_SIZE_T)(size) > (CHUNK_SIZE_T)(nb)) {
-
- mm = (char*)(MMAP(0, size, PROT_READ|PROT_WRITE, MAP_PRIVATE));
-
- if (mm != (char*)(MORECORE_FAILURE)) {
-
- /*
- The offset to the start of the mmapped region is stored
- in the prev_size field of the chunk. This allows us to adjust
- returned start address to meet alignment requirements here
- and in memalign(), and still be able to compute proper
- address argument for later munmap in free() and realloc().
- */
-
- front_misalign = (INTERNAL_SIZE_T)chunk2mem(mm) & MALLOC_ALIGN_MASK;
- if (front_misalign > 0) {
- correction = MALLOC_ALIGNMENT - front_misalign;
- p = (mchunkptr)(mm + correction);
- p->prev_size = correction;
- set_head(p, (size - correction) |IS_MMAPPED);
- }
- else {
- p = (mchunkptr)mm;
- p->prev_size = 0;
- set_head(p, size|IS_MMAPPED);
- }
-
- /* update statistics */
-
- if (++av->n_mmaps > av->max_n_mmaps)
- av->max_n_mmaps = av->n_mmaps;
-
- sum = av->mmapped_mem += size;
- if (sum > (CHUNK_SIZE_T)(av->max_mmapped_mem))
- av->max_mmapped_mem = sum;
- sum += av->sbrked_mem;
- if (sum > (CHUNK_SIZE_T)(av->max_total_mem))
- av->max_total_mem = sum;
-
- check_chunk(p);
-
- return chunk2mem(p);
- }
- }
- }
-#endif
-
- /* Record incoming configuration of top */
-
- old_top = av->top;
- old_size = chunksize(old_top);
- old_end = (char*)(chunk_at_offset(old_top, old_size));
-
- brk = snd_brk = (char*)(MORECORE_FAILURE);
-
- /*
- If not the first time through, we require old_size to be
- at least MINSIZE and to have prev_inuse set.
- */
-
- assert((old_top == initial_top(av) && old_size == 0) ||
- ((CHUNK_SIZE_T) (old_size) >= MINSIZE &&
- prev_inuse(old_top)));
-
- /* Precondition: not enough current space to satisfy nb request */
- assert((CHUNK_SIZE_T)(old_size) < (CHUNK_SIZE_T)(nb + MINSIZE));
-
- /* Precondition: all fastbins are consolidated */
- assert(!have_fastchunks(av));
-
-
- /* Request enough space for nb + pad + overhead */
-
- size = nb + av->top_pad + MINSIZE;
-
- /*
- If contiguous, we can subtract out existing space that we hope to
- combine with new space. We add it back later only if
- we don't actually get contiguous space.
- */
-
- if (contiguous(av))
- size -= old_size;
-
- /*
- Round to a multiple of page size.
- If MORECORE is not contiguous, this ensures that we only call it
- with whole-page arguments. And if MORECORE is contiguous and
- this is not first time through, this preserves page-alignment of
- previous calls. Otherwise, we correct to page-align below.
- */
-
- size = (size + pagemask) & ~pagemask;
-
- /*
- Don't try to call MORECORE if argument is so big as to appear
- negative. Note that since mmap takes size_t arg, it may succeed
- below even if we cannot call MORECORE.
- */
-
- if (size > 0)
- brk = (char*)(MORECORE(size));
-
- /*
- If have mmap, try using it as a backup when MORECORE fails or
- cannot be used. This is worth doing on systems that have "holes" in
- address space, so sbrk cannot extend to give contiguous space, but
- space is available elsewhere. Note that we ignore mmap max count
- and threshold limits, since the space will not be used as a
- segregated mmap region.
- */
-
-#if HAVE_MMAP
- if (brk == (char*)(MORECORE_FAILURE)) {
-
- /* Cannot merge with old top, so add its size back in */
- if (contiguous(av))
- size = (size + old_size + pagemask) & ~pagemask;
-
- /* If we are relying on mmap as backup, then use larger units */
- if ((CHUNK_SIZE_T)(size) < (CHUNK_SIZE_T)(MMAP_AS_MORECORE_SIZE))
- size = MMAP_AS_MORECORE_SIZE;
-
- /* Don't try if size wraps around 0 */
- if ((CHUNK_SIZE_T)(size) > (CHUNK_SIZE_T)(nb)) {
-
- brk = (char*)(MMAP(0, size, PROT_READ|PROT_WRITE, MAP_PRIVATE));
-
- if (brk != (char*)(MORECORE_FAILURE)) {
-
- /* We do not need, and cannot use, another sbrk call to find end */
- snd_brk = brk + size;
-
- /*
- Record that we no longer have a contiguous sbrk region.
- After the first time mmap is used as backup, we do not
- ever rely on contiguous space since this could incorrectly
- bridge regions.
- */
- set_noncontiguous(av);
- }
- }
- }
-#endif
-
- if (brk != (char*)(MORECORE_FAILURE)) {
- av->sbrked_mem += size;
-
- /*
- If MORECORE extends previous space, we can likewise extend top size.
- */
-
- if (brk == old_end && snd_brk == (char*)(MORECORE_FAILURE)) {
- set_head(old_top, (size + old_size) | PREV_INUSE);
- }
-
- /*
- Otherwise, make adjustments:
-
- * If the first time through or noncontiguous, we need to call sbrk
- just to find out where the end of memory lies.
-
- * We need to ensure that all returned chunks from malloc will meet
- MALLOC_ALIGNMENT
-
- * If there was an intervening foreign sbrk, we need to adjust sbrk
- request size to account for fact that we will not be able to
- combine new space with existing space in old_top.
-
- * Almost all systems internally allocate whole pages at a time, in
- which case we might as well use the whole last page of request.
- So we allocate enough more memory to hit a page boundary now,
- which in turn causes future contiguous calls to page-align.
- */
-
- else {
- front_misalign = 0;
- end_misalign = 0;
- correction = 0;
- aligned_brk = brk;
-
- /*
- If MORECORE returns an address lower than we have seen before,
- we know it isn't really contiguous. This and some subsequent
- checks help cope with non-conforming MORECORE functions and
- the presence of "foreign" calls to MORECORE from outside of
- malloc or by other threads. We cannot guarantee to detect
- these in all cases, but cope with the ones we do detect.
- */
- if (contiguous(av) && old_size != 0 && brk < old_end) {
- set_noncontiguous(av);
- }
-
- /* handle contiguous cases */
- if (contiguous(av)) {
-
- /*
- We can tolerate forward non-contiguities here (usually due
- to foreign calls) but treat them as part of our space for
- stats reporting.
- */
- if (old_size != 0)
- av->sbrked_mem += brk - old_end;
-
- /* Guarantee alignment of first new chunk made from this space */
-
- front_misalign = (INTERNAL_SIZE_T)chunk2mem(brk) & MALLOC_ALIGN_MASK;
- if (front_misalign > 0) {
-
- /*
- Skip over some bytes to arrive at an aligned position.
- We don't need to specially mark these wasted front bytes.
- They will never be accessed anyway because
- prev_inuse of av->top (and any chunk created from its start)
- is always true after initialization.
- */
-
- correction = MALLOC_ALIGNMENT - front_misalign;
- aligned_brk += correction;
- }
-
- /*
- If this isn't adjacent to existing space, then we will not
- be able to merge with old_top space, so must add to 2nd request.
- */
-
- correction += old_size;
-
- /* Extend the end address to hit a page boundary */
- end_misalign = (INTERNAL_SIZE_T)(brk + size + correction);
- correction += ((end_misalign + pagemask) & ~pagemask) - end_misalign;
-
- assert(correction >= 0);
- snd_brk = (char*)(MORECORE(correction));
-
- if (snd_brk == (char*)(MORECORE_FAILURE)) {
- /*
- If can't allocate correction, try to at least find out current
- brk. It might be enough to proceed without failing.
- */
- correction = 0;
- snd_brk = (char*)(MORECORE(0));
- }
- else if (snd_brk < brk) {
- /*
- If the second call gives noncontiguous space even though
- it says it won't, the only course of action is to ignore
- results of second call, and conservatively estimate where
- the first call left us. Also set noncontiguous, so this
- won't happen again, leaving at most one hole.
-
- Note that this check is intrinsically incomplete. Because
- MORECORE is allowed to give more space than we ask for,
- there is no reliable way to detect a noncontiguity
- producing a forward gap for the second call.
- */
- snd_brk = brk + size;
- correction = 0;
- set_noncontiguous(av);
- }
-
- }
-
- /* handle non-contiguous cases */
- else {
- /* MORECORE/mmap must correctly align */
- assert(aligned_OK(chunk2mem(brk)));
-
- /* Find out current end of memory */
- if (snd_brk == (char*)(MORECORE_FAILURE)) {
- snd_brk = (char*)(MORECORE(0));
- av->sbrked_mem += snd_brk - brk - size;
- }
- }
-
- /* Adjust top based on results of second sbrk */
- if (snd_brk != (char*)(MORECORE_FAILURE)) {
- av->top = (mchunkptr)aligned_brk;
- set_head(av->top, (snd_brk - aligned_brk + correction) | PREV_INUSE);
- av->sbrked_mem += correction;
-
- /*
- If not the first time through, we either have a
- gap due to foreign sbrk or a non-contiguous region. Insert a
- double fencepost at old_top to prevent consolidation with space
- we don't own. These fenceposts are artificial chunks that are
- marked as inuse and are in any case too small to use. We need
- two to make sizes and alignments work out.
- */
-
- if (old_size != 0) {
- /*
- Shrink old_top to insert fenceposts, keeping size a
- multiple of MALLOC_ALIGNMENT. We know there is at least
- enough space in old_top to do this.
- */
- old_size = (old_size - 3*SIZE_SZ) & ~MALLOC_ALIGN_MASK;
- set_head(old_top, old_size | PREV_INUSE);
-
- /*
- Note that the following assignments completely overwrite
- old_top when old_size was previously MINSIZE. This is
- intentional. We need the fencepost, even if old_top otherwise gets
- lost.
- */
- chunk_at_offset(old_top, old_size )->size =
- SIZE_SZ|PREV_INUSE;
-
- chunk_at_offset(old_top, old_size + SIZE_SZ)->size =
- SIZE_SZ|PREV_INUSE;
-
- /*
- If possible, release the rest, suppressing trimming.
- */
- if (old_size >= MINSIZE) {
- INTERNAL_SIZE_T tt = av->trim_threshold;
- av->trim_threshold = (INTERNAL_SIZE_T)(-1);
- fREe(chunk2mem(old_top));
- av->trim_threshold = tt;
- }
- }
- }
- }
-
- /* Update statistics */
- sum = av->sbrked_mem;
- if (sum > (CHUNK_SIZE_T)(av->max_sbrked_mem))
- av->max_sbrked_mem = sum;
-
- sum += av->mmapped_mem;
- if (sum > (CHUNK_SIZE_T)(av->max_total_mem))
- av->max_total_mem = sum;
-
- check_malloc_state();
-
- /* finally, do the allocation */
-
- p = av->top;
- size = chunksize(p);
-
- /* check that one of the above allocation paths succeeded */
- if ((CHUNK_SIZE_T)(size) >= (CHUNK_SIZE_T)(nb + MINSIZE)) {
- remainder_size = size - nb;
- remainder = chunk_at_offset(p, nb);
- av->top = remainder;
- set_head(p, nb | PREV_INUSE);
- set_head(remainder, remainder_size | PREV_INUSE);
- check_malloced_chunk(p, nb);
- return chunk2mem(p);
- }
-
- }
-
- /* catch all failure paths */
- MALLOC_FAILURE_ACTION;
- return 0;
-}
-
-
-
-#ifndef MORECORE_CANNOT_TRIM
-/*
- sYSTRIm is an inverse of sorts to sYSMALLOc. It gives memory back
- to the system (via negative arguments to sbrk) if there is unused
- memory at the `high' end of the malloc pool. It is called
- automatically by free() when top space exceeds the trim
- threshold. It is also called by the public malloc_trim routine. It
- returns 1 if it actually released any memory, else 0.
-*/
-
-#if __STD_C
-static int sYSTRIm(size_t pad, mstate av)
-#else
-static int sYSTRIm(pad, av) size_t pad; mstate av;
-#endif
-{
- long top_size; /* Amount of top-most memory */
- long extra; /* Amount to release */
- long released; /* Amount actually released */
- char* current_brk; /* address returned by pre-check sbrk call */
- char* new_brk; /* address returned by post-check sbrk call */
- size_t pagesz;
-
- pagesz = av->pagesize;
- top_size = chunksize(av->top);
-
- /* Release in pagesize units, keeping at least one page */
- extra = ((top_size - pad - MINSIZE + (pagesz-1)) / pagesz - 1) * pagesz;
-
- if (extra > 0) {
-
- /*
- Only proceed if end of memory is where we last set it.
- This avoids problems if there were foreign sbrk calls.
- */
- current_brk = (char*)(MORECORE(0));
- if (current_brk == (char*)(av->top) + top_size) {
-
- /*
- Attempt to release memory. We ignore MORECORE return value,
- and instead call again to find out where new end of memory is.
- This avoids problems if first call releases less than we asked,
- of if failure somehow altered brk value. (We could still
- encounter problems if it altered brk in some very bad way,
- but the only thing we can do is adjust anyway, which will cause
- some downstream failure.)
- */
-
- MORECORE(-extra);
- new_brk = (char*)(MORECORE(0));
-
- if (new_brk != (char*)MORECORE_FAILURE) {
- released = (long)(current_brk - new_brk);
-
- if (released != 0) {
- /* Success. Adjust top. */
- av->sbrked_mem -= released;
- set_head(av->top, (top_size - released) | PREV_INUSE);
- check_malloc_state();
- return 1;
- }
- }
- }
- }
- return 0;
-}
-#endif /*MORECORE_CANNOT_TRIM*/
-
-/*
- ------------------------------ malloc ------------------------------
-*/
-
-
-#if __STD_C
-Void_t* mALLOc(size_t bytes)
-#else
- Void_t* mALLOc(bytes) size_t bytes;
-#endif
-{
- mstate av = get_malloc_state();
-
- INTERNAL_SIZE_T nb; /* normalized request size */
- unsigned int idx; /* associated bin index */
- mbinptr bin; /* associated bin */
- mfastbinptr* fb; /* associated fastbin */
-
- mchunkptr victim; /* inspected/selected chunk */
- INTERNAL_SIZE_T size; /* its size */
- int victim_index; /* its bin index */
-
- mchunkptr remainder; /* remainder from a split */
- CHUNK_SIZE_T remainder_size; /* its size */
-
- unsigned int block; /* bit map traverser */
- unsigned int bit; /* bit map traverser */
- unsigned int map; /* current word of binmap */
-
- mchunkptr fwd; /* misc temp for linking */
- mchunkptr bck; /* misc temp for linking */
-
- /*
- Convert request size to internal form by adding SIZE_SZ bytes
- overhead plus possibly more to obtain necessary alignment and/or
- to obtain a size of at least MINSIZE, the smallest allocatable
- size. Also, checked_request2size traps (returning 0) request sizes
- that are so large that they wrap around zero when padded and
- aligned.
- */
-
- checked_request2size(bytes, nb);
-
- /*
- Bypass search if no frees yet
- */
- if (!have_anychunks(av)) {
- if (av->max_fast == 0) /* initialization check */
- malloc_consolidate(av);
- goto use_top;
- }
-
- /*
- If the size qualifies as a fastbin, first check corresponding bin.
- */
-
- if ((CHUNK_SIZE_T)(nb) <= (CHUNK_SIZE_T)(av->max_fast)) {
- fb = &(av->fastbins[(fastbin_index(nb))]);
- if ( (victim = *fb) != 0) {
- *fb = victim->fd;
- check_remalloced_chunk(victim, nb);
- return chunk2mem(victim);
- }
- }
-
- /*
- If a small request, check regular bin. Since these "smallbins"
- hold one size each, no searching within bins is necessary.
- (For a large request, we need to wait until unsorted chunks are
- processed to find best fit. But for small ones, fits are exact
- anyway, so we can check now, which is faster.)
- */
-
- if (in_smallbin_range(nb)) {
- idx = smallbin_index(nb);
- bin = bin_at(av,idx);
-
- if ( (victim = last(bin)) != bin) {
- bck = victim->bk;
- set_inuse_bit_at_offset(victim, nb);
- bin->bk = bck;
- bck->fd = bin;
-
- check_malloced_chunk(victim, nb);
- return chunk2mem(victim);
- }
- }
-
- /*
- If this is a large request, consolidate fastbins before continuing.
- While it might look excessive to kill all fastbins before
- even seeing if there is space available, this avoids
- fragmentation problems normally associated with fastbins.
- Also, in practice, programs tend to have runs of either small or
- large requests, but less often mixtures, so consolidation is not
- invoked all that often in most programs. And the programs that
- it is called frequently in otherwise tend to fragment.
- */
-
- else {
- idx = largebin_index(nb);
- if (have_fastchunks(av))
- malloc_consolidate(av);
- }
-
- /*
- Process recently freed or remaindered chunks, taking one only if
- it is exact fit, or, if this a small request, the chunk is remainder from
- the most recent non-exact fit. Place other traversed chunks in
- bins. Note that this step is the only place in any routine where
- chunks are placed in bins.
- */
-
- while ( (victim = unsorted_chunks(av)->bk) != unsorted_chunks(av)) {
- bck = victim->bk;
- size = chunksize(victim);
-
- /*
- If a small request, try to use last remainder if it is the
- only chunk in unsorted bin. This helps promote locality for
- runs of consecutive small requests. This is the only
- exception to best-fit, and applies only when there is
- no exact fit for a small chunk.
- */
-
- if (in_smallbin_range(nb) &&
- bck == unsorted_chunks(av) &&
- victim == av->last_remainder &&
- (CHUNK_SIZE_T)(size) > (CHUNK_SIZE_T)(nb + MINSIZE)) {
-
- /* split and reattach remainder */
- remainder_size = size - nb;
- remainder = chunk_at_offset(victim, nb);
- unsorted_chunks(av)->bk = unsorted_chunks(av)->fd = remainder;
- av->last_remainder = remainder;
- remainder->bk = remainder->fd = unsorted_chunks(av);
-
- set_head(victim, nb | PREV_INUSE);
- set_head(remainder, remainder_size | PREV_INUSE);
- set_foot(remainder, remainder_size);
-
- check_malloced_chunk(victim, nb);
- return chunk2mem(victim);
- }
-
- /* remove from unsorted list */
- unsorted_chunks(av)->bk = bck;
- bck->fd = unsorted_chunks(av);
-
- /* Take now instead of binning if exact fit */
-
- if (size == nb) {
- set_inuse_bit_at_offset(victim, size);
- check_malloced_chunk(victim, nb);
- return chunk2mem(victim);
- }
-
- /* place chunk in bin */
-
- if (in_smallbin_range(size)) {
- victim_index = smallbin_index(size);
- bck = bin_at(av, victim_index);
- fwd = bck->fd;
- }
- else {
- victim_index = largebin_index(size);
- bck = bin_at(av, victim_index);
- fwd = bck->fd;
-
- if (fwd != bck) {
- /* if smaller than smallest, place first */
- if ((CHUNK_SIZE_T)(size) < (CHUNK_SIZE_T)(bck->bk->size)) {
- fwd = bck;
- bck = bck->bk;
- }
- else if ((CHUNK_SIZE_T)(size) >=
- (CHUNK_SIZE_T)(FIRST_SORTED_BIN_SIZE)) {
-
- /* maintain large bins in sorted order */
- size |= PREV_INUSE; /* Or with inuse bit to speed comparisons */
- while ((CHUNK_SIZE_T)(size) < (CHUNK_SIZE_T)(fwd->size))
- fwd = fwd->fd;
- bck = fwd->bk;
- }
- }
- }
-
- mark_bin(av, victim_index);
- victim->bk = bck;
- victim->fd = fwd;
- fwd->bk = victim;
- bck->fd = victim;
- }
-
- /*
- If a large request, scan through the chunks of current bin to
- find one that fits. (This will be the smallest that fits unless
- FIRST_SORTED_BIN_SIZE has been changed from default.) This is
- the only step where an unbounded number of chunks might be
- scanned without doing anything useful with them. However the
- lists tend to be short.
- */
-
- if (!in_smallbin_range(nb)) {
- bin = bin_at(av, idx);
-
- for (victim = last(bin); victim != bin; victim = victim->bk) {
- size = chunksize(victim);
-
- if ((CHUNK_SIZE_T)(size) >= (CHUNK_SIZE_T)(nb)) {
- remainder_size = size - nb;
- unlink(victim, bck, fwd);
-
- /* Exhaust */
- if (remainder_size < MINSIZE) {
- set_inuse_bit_at_offset(victim, size);
- check_malloced_chunk(victim, nb);
- return chunk2mem(victim);
- }
- /* Split */
- else {
- remainder = chunk_at_offset(victim, nb);
- unsorted_chunks(av)->bk = unsorted_chunks(av)->fd = remainder;
- remainder->bk = remainder->fd = unsorted_chunks(av);
- set_head(victim, nb | PREV_INUSE);
- set_head(remainder, remainder_size | PREV_INUSE);
- set_foot(remainder, remainder_size);
- check_malloced_chunk(victim, nb);
- return chunk2mem(victim);
- }
- }
- }
- }
-
- /*
- Search for a chunk by scanning bins, starting with next largest
- bin. This search is strictly by best-fit; i.e., the smallest
- (with ties going to approximately the least recently used) chunk
- that fits is selected.
-
- The bitmap avoids needing to check that most blocks are nonempty.
- */
-
- ++idx;
- bin = bin_at(av,idx);
- block = idx2block(idx);
- map = av->binmap[block];
- bit = idx2bit(idx);
-
- for (;;) {
-
- /* Skip rest of block if there are no more set bits in this block. */
- if (bit > map || bit == 0) {
- do {
- if (++block >= BINMAPSIZE) /* out of bins */
- goto use_top;
- } while ( (map = av->binmap[block]) == 0);
-
- bin = bin_at(av, (block << BINMAPSHIFT));
- bit = 1;
- }
-
- /* Advance to bin with set bit. There must be one. */
- while ((bit & map) == 0) {
- bin = next_bin(bin);
- bit <<= 1;
- assert(bit != 0);
- }
-
- /* Inspect the bin. It is likely to be non-empty */
- victim = last(bin);
-
- /* If a false alarm (empty bin), clear the bit. */
- if (victim == bin) {
- av->binmap[block] = map &= ~bit; /* Write through */
- bin = next_bin(bin);
- bit <<= 1;
- }
-
- else {
- size = chunksize(victim);
-
- /* We know the first chunk in this bin is big enough to use. */
- assert((CHUNK_SIZE_T)(size) >= (CHUNK_SIZE_T)(nb));
-
- remainder_size = size - nb;
-
- /* unlink */
- bck = victim->bk;
- bin->bk = bck;
- bck->fd = bin;
-
- /* Exhaust */
- if (remainder_size < MINSIZE) {
- set_inuse_bit_at_offset(victim, size);
- check_malloced_chunk(victim, nb);
- return chunk2mem(victim);
- }
-
- /* Split */
- else {
- remainder = chunk_at_offset(victim, nb);
-
- unsorted_chunks(av)->bk = unsorted_chunks(av)->fd = remainder;
- remainder->bk = remainder->fd = unsorted_chunks(av);
- /* advertise as last remainder */
- if (in_smallbin_range(nb))
- av->last_remainder = remainder;
-
- set_head(victim, nb | PREV_INUSE);
- set_head(remainder, remainder_size | PREV_INUSE);
- set_foot(remainder, remainder_size);
- check_malloced_chunk(victim, nb);
- return chunk2mem(victim);
- }
- }
- }
-
- use_top:
- /*
- If large enough, split off the chunk bordering the end of memory
- (held in av->top). Note that this is in accord with the best-fit
- search rule. In effect, av->top is treated as larger (and thus
- less well fitting) than any other available chunk since it can
- be extended to be as large as necessary (up to system
- limitations).
-
- We require that av->top always exists (i.e., has size >=
- MINSIZE) after initialization, so if it would otherwise be
- exhuasted by current request, it is replenished. (The main
- reason for ensuring it exists is that we may need MINSIZE space
- to put in fenceposts in sysmalloc.)
- */
-
- victim = av->top;
- size = chunksize(victim);
-
- if ((CHUNK_SIZE_T)(size) >= (CHUNK_SIZE_T)(nb + MINSIZE)) {
- remainder_size = size - nb;
- remainder = chunk_at_offset(victim, nb);
- av->top = remainder;
- set_head(victim, nb | PREV_INUSE);
- set_head(remainder, remainder_size | PREV_INUSE);
-
- check_malloced_chunk(victim, nb);
- return chunk2mem(victim);
- }
-
- /*
- If no space in top, relay to handle system-dependent cases
- */
- return sYSMALLOc(nb, av);
-}
-
-/*
- ------------------------------ free ------------------------------
-*/
-
-#if __STD_C
-void fREe(Void_t* mem)
-#else
-void fREe(mem) Void_t* mem;
-#endif
-{
- mstate av = get_malloc_state();
-
- mchunkptr p; /* chunk corresponding to mem */
- INTERNAL_SIZE_T size; /* its size */
- mfastbinptr* fb; /* associated fastbin */
- mchunkptr nextchunk; /* next contiguous chunk */
- INTERNAL_SIZE_T nextsize; /* its size */
- int nextinuse; /* true if nextchunk is used */
- INTERNAL_SIZE_T prevsize; /* size of previous contiguous chunk */
- mchunkptr bck; /* misc temp for linking */
- mchunkptr fwd; /* misc temp for linking */
-
- /* free(0) has no effect */
- if (mem != 0) {
- p = mem2chunk(mem);
- size = chunksize(p);
-
- check_inuse_chunk(p);
-
- /*
- If eligible, place chunk on a fastbin so it can be found
- and used quickly in malloc.
- */
-
- if ((CHUNK_SIZE_T)(size) <= (CHUNK_SIZE_T)(av->max_fast)
-
-#if TRIM_FASTBINS
- /*
- If TRIM_FASTBINS set, don't place chunks
- bordering top into fastbins
- */
- && (chunk_at_offset(p, size) != av->top)
-#endif
- ) {
-
- set_fastchunks(av);
- fb = &(av->fastbins[fastbin_index(size)]);
- p->fd = *fb;
- *fb = p;
- }
-
- /*
- Consolidate other non-mmapped chunks as they arrive.
- */
-
- else if (!chunk_is_mmapped(p)) {
- set_anychunks(av);
-
- nextchunk = chunk_at_offset(p, size);
- nextsize = chunksize(nextchunk);
-
- /* consolidate backward */
- if (!prev_inuse(p)) {
- prevsize = p->prev_size;
- size += prevsize;
- p = chunk_at_offset(p, -((long) prevsize));
- unlink(p, bck, fwd);
- }
-
- if (nextchunk != av->top) {
- /* get and clear inuse bit */
- nextinuse = inuse_bit_at_offset(nextchunk, nextsize);
- set_head(nextchunk, nextsize);
-
- /* consolidate forward */
- if (!nextinuse) {
- unlink(nextchunk, bck, fwd);
- size += nextsize;
- }
-
- /*
- Place the chunk in unsorted chunk list. Chunks are
- not placed into regular bins until after they have
- been given one chance to be used in malloc.
- */
-
- bck = unsorted_chunks(av);
- fwd = bck->fd;
- p->bk = bck;
- p->fd = fwd;
- bck->fd = p;
- fwd->bk = p;
-
- set_head(p, size | PREV_INUSE);
- set_foot(p, size);
-
- check_free_chunk(p);
- }
-
- /*
- If the chunk borders the current high end of memory,
- consolidate into top
- */
-
- else {
- size += nextsize;
- set_head(p, size | PREV_INUSE);
- av->top = p;
- check_chunk(p);
- }
-
- /*
- If freeing a large space, consolidate possibly-surrounding
- chunks. Then, if the total unused topmost memory exceeds trim
- threshold, ask malloc_trim to reduce top.
-
- Unless max_fast is 0, we don't know if there are fastbins
- bordering top, so we cannot tell for sure whether threshold
- has been reached unless fastbins are consolidated. But we
- don't want to consolidate on each free. As a compromise,
- consolidation is performed if FASTBIN_CONSOLIDATION_THRESHOLD
- is reached.
- */
-
- if ((CHUNK_SIZE_T)(size) >= FASTBIN_CONSOLIDATION_THRESHOLD) {
- if (have_fastchunks(av))
- malloc_consolidate(av);
-
-#ifndef MORECORE_CANNOT_TRIM
- if ((CHUNK_SIZE_T)(chunksize(av->top)) >=
- (CHUNK_SIZE_T)(av->trim_threshold))
- sYSTRIm(av->top_pad, av);
-#endif
- }
-
- }
- /*
- If the chunk was allocated via mmap, release via munmap()
- Note that if HAVE_MMAP is false but chunk_is_mmapped is
- true, then user must have overwritten memory. There's nothing
- we can do to catch this error unless DEBUG is set, in which case
- check_inuse_chunk (above) will have triggered error.
- */
-
- else {
-#if HAVE_MMAP
- int ret;
- INTERNAL_SIZE_T offset = p->prev_size;
- av->n_mmaps--;
- av->mmapped_mem -= (size + offset);
- ret = munmap((char*)p - offset, size + offset);
- /* munmap returns non-zero on failure */
- assert(ret == 0);
-#endif
- }
- }
-}
-
-/*
- ------------------------- malloc_consolidate -------------------------
-
- malloc_consolidate is a specialized version of free() that tears
- down chunks held in fastbins. Free itself cannot be used for this
- purpose since, among other things, it might place chunks back onto
- fastbins. So, instead, we need to use a minor variant of the same
- code.
-
- Also, because this routine needs to be called the first time through
- malloc anyway, it turns out to be the perfect place to trigger
- initialization code.
-*/
-
-#if __STD_C
-static void malloc_consolidate(mstate av)
-#else
-static void malloc_consolidate(av) mstate av;
-#endif
-{
- mfastbinptr* fb; /* current fastbin being consolidated */
- mfastbinptr* maxfb; /* last fastbin (for loop control) */
- mchunkptr p; /* current chunk being consolidated */
- mchunkptr nextp; /* next chunk to consolidate */
- mchunkptr unsorted_bin; /* bin header */
- mchunkptr first_unsorted; /* chunk to link to */
-
- /* These have same use as in free() */
- mchunkptr nextchunk;
- INTERNAL_SIZE_T size;
- INTERNAL_SIZE_T nextsize;
- INTERNAL_SIZE_T prevsize;
- int nextinuse;
- mchunkptr bck;
- mchunkptr fwd;
-
- /*
- If max_fast is 0, we know that av hasn't
- yet been initialized, in which case do so below
- */
-
- if (av->max_fast != 0) {
- clear_fastchunks(av);
-
- unsorted_bin = unsorted_chunks(av);
-
- /*
- Remove each chunk from fast bin and consolidate it, placing it
- then in unsorted bin. Among other reasons for doing this,
- placing in unsorted bin avoids needing to calculate actual bins
- until malloc is sure that chunks aren't immediately going to be
- reused anyway.
- */
-
- maxfb = &(av->fastbins[fastbin_index(av->max_fast)]);
- fb = &(av->fastbins[0]);
- do {
- if ( (p = *fb) != 0) {
- *fb = 0;
-
- do {
- check_inuse_chunk(p);
- nextp = p->fd;
-
- /* Slightly streamlined version of consolidation code in free() */
- size = p->size & ~PREV_INUSE;
- nextchunk = chunk_at_offset(p, size);
- nextsize = chunksize(nextchunk);
-
- if (!prev_inuse(p)) {
- prevsize = p->prev_size;
- size += prevsize;
- p = chunk_at_offset(p, -((long) prevsize));
- unlink(p, bck, fwd);
- }
-
- if (nextchunk != av->top) {
- nextinuse = inuse_bit_at_offset(nextchunk, nextsize);
- set_head(nextchunk, nextsize);
-
- if (!nextinuse) {
- size += nextsize;
- unlink(nextchunk, bck, fwd);
- }
-
- first_unsorted = unsorted_bin->fd;
- unsorted_bin->fd = p;
- first_unsorted->bk = p;
-
- set_head(p, size | PREV_INUSE);
- p->bk = unsorted_bin;
- p->fd = first_unsorted;
- set_foot(p, size);
- }
-
- else {
- size += nextsize;
- set_head(p, size | PREV_INUSE);
- av->top = p;
- }
-
- } while ( (p = nextp) != 0);
-
- }
- } while (fb++ != maxfb);
- }
- else {
- malloc_init_state(av);
- check_malloc_state();
- }
-}
-
-/*
- ------------------------------ realloc ------------------------------
-*/
-
-
-#if __STD_C
-Void_t* rEALLOc(Void_t* oldmem, size_t bytes)
-#else
-Void_t* rEALLOc(oldmem, bytes) Void_t* oldmem; size_t bytes;
-#endif
-{
- mstate av = get_malloc_state();
-
- INTERNAL_SIZE_T nb; /* padded request size */
-
- mchunkptr oldp; /* chunk corresponding to oldmem */
- INTERNAL_SIZE_T oldsize; /* its size */
-
- mchunkptr newp; /* chunk to return */
- INTERNAL_SIZE_T newsize; /* its size */
- Void_t* newmem; /* corresponding user mem */
-
- mchunkptr next; /* next contiguous chunk after oldp */
-
- mchunkptr remainder; /* extra space at end of newp */
- CHUNK_SIZE_T remainder_size; /* its size */
-
- mchunkptr bck; /* misc temp for linking */
- mchunkptr fwd; /* misc temp for linking */
-
- CHUNK_SIZE_T copysize; /* bytes to copy */
- unsigned int ncopies; /* INTERNAL_SIZE_T words to copy */
- INTERNAL_SIZE_T* s; /* copy source */
- INTERNAL_SIZE_T* d; /* copy destination */
-
-
-#ifdef REALLOC_ZERO_BYTES_FREES
- if (bytes == 0) {
- fREe(oldmem);
- return 0;
- }
-#endif
-
- /* realloc of null is supposed to be same as malloc */
- if (oldmem == 0) return mALLOc(bytes);
-
- checked_request2size(bytes, nb);
-
- oldp = mem2chunk(oldmem);
- oldsize = chunksize(oldp);
-
- check_inuse_chunk(oldp);
-
- if (!chunk_is_mmapped(oldp)) {
-
- if ((CHUNK_SIZE_T)(oldsize) >= (CHUNK_SIZE_T)(nb)) {
- /* already big enough; split below */
- newp = oldp;
- newsize = oldsize;
- }
-
- else {
- next = chunk_at_offset(oldp, oldsize);
-
- /* Try to expand forward into top */
- if (next == av->top &&
- (CHUNK_SIZE_T)(newsize = oldsize + chunksize(next)) >=
- (CHUNK_SIZE_T)(nb + MINSIZE)) {
- set_head_size(oldp, nb);
- av->top = chunk_at_offset(oldp, nb);
- set_head(av->top, (newsize - nb) | PREV_INUSE);
- return chunk2mem(oldp);
- }
-
- /* Try to expand forward into next chunk; split off remainder below */
- else if (next != av->top &&
- !inuse(next) &&
- (CHUNK_SIZE_T)(newsize = oldsize + chunksize(next)) >=
- (CHUNK_SIZE_T)(nb)) {
- newp = oldp;
- unlink(next, bck, fwd);
- }
-
- /* allocate, copy, free */
- else {
- newmem = mALLOc(nb - MALLOC_ALIGN_MASK);
- if (newmem == 0)
- return 0; /* propagate failure */
-
- newp = mem2chunk(newmem);
- newsize = chunksize(newp);
-
- /*
- Avoid copy if newp is next chunk after oldp.
- */
- if (newp == next) {
- newsize += oldsize;
- newp = oldp;
- }
- else {
- /*
- Unroll copy of <= 36 bytes (72 if 8byte sizes)
- We know that contents have an odd number of
- INTERNAL_SIZE_T-sized words; minimally 3.
- */
-
- copysize = oldsize - SIZE_SZ;
- s = (INTERNAL_SIZE_T*)(oldmem);
- d = (INTERNAL_SIZE_T*)(newmem);
- ncopies = copysize / sizeof(INTERNAL_SIZE_T);
- assert(ncopies >= 3);
-
- if (ncopies > 9)
- MALLOC_COPY(d, s, copysize);
-
- else {
- *(d+0) = *(s+0);
- *(d+1) = *(s+1);
- *(d+2) = *(s+2);
- if (ncopies > 4) {
- *(d+3) = *(s+3);
- *(d+4) = *(s+4);
- if (ncopies > 6) {
- *(d+5) = *(s+5);
- *(d+6) = *(s+6);
- if (ncopies > 8) {
- *(d+7) = *(s+7);
- *(d+8) = *(s+8);
- }
- }
- }
- }
-
- fREe(oldmem);
- check_inuse_chunk(newp);
- return chunk2mem(newp);
- }
- }
- }
-
- /* If possible, free extra space in old or extended chunk */
-
- assert((CHUNK_SIZE_T)(newsize) >= (CHUNK_SIZE_T)(nb));
-
- remainder_size = newsize - nb;
-
- if (remainder_size < MINSIZE) { /* not enough extra to split off */
- set_head_size(newp, newsize);
- set_inuse_bit_at_offset(newp, newsize);
- }
- else { /* split remainder */
- remainder = chunk_at_offset(newp, nb);
- set_head_size(newp, nb);
- set_head(remainder, remainder_size | PREV_INUSE);
- /* Mark remainder as inuse so free() won't complain */
- set_inuse_bit_at_offset(remainder, remainder_size);
- fREe(chunk2mem(remainder));
- }
-
- check_inuse_chunk(newp);
- return chunk2mem(newp);
- }
-
- /*
- Handle mmap cases
- */
-
- else {
-#if HAVE_MMAP
-
-#if HAVE_MREMAP
- INTERNAL_SIZE_T offset = oldp->prev_size;
- size_t pagemask = av->pagesize - 1;
- char *cp;
- CHUNK_SIZE_T sum;
-
- /* Note the extra SIZE_SZ overhead */
- newsize = (nb + offset + SIZE_SZ + pagemask) & ~pagemask;
-
- /* don't need to remap if still within same page */
- if (oldsize == newsize - offset)
- return oldmem;
-
- cp = (char*)mremap((char*)oldp - offset, oldsize + offset, newsize, 1);
-
- if (cp != (char*)MORECORE_FAILURE) {
-
- newp = (mchunkptr)(cp + offset);
- set_head(newp, (newsize - offset)|IS_MMAPPED);
-
- assert(aligned_OK(chunk2mem(newp)));
- assert((newp->prev_size == offset));
-
- /* update statistics */
- sum = av->mmapped_mem += newsize - oldsize;
- if (sum > (CHUNK_SIZE_T)(av->max_mmapped_mem))
- av->max_mmapped_mem = sum;
- sum += av->sbrked_mem;
- if (sum > (CHUNK_SIZE_T)(av->max_total_mem))
- av->max_total_mem = sum;
-
- return chunk2mem(newp);
- }
-#endif
-
- /* Note the extra SIZE_SZ overhead. */
- if ((CHUNK_SIZE_T)(oldsize) >= (CHUNK_SIZE_T)(nb + SIZE_SZ))
- newmem = oldmem; /* do nothing */
- else {
- /* Must alloc, copy, free. */
- newmem = mALLOc(nb - MALLOC_ALIGN_MASK);
- if (newmem != 0) {
- MALLOC_COPY(newmem, oldmem, oldsize - 2*SIZE_SZ);
- fREe(oldmem);
- }
- }
- return newmem;
-
-#else
- /* If !HAVE_MMAP, but chunk_is_mmapped, user must have overwritten mem */
- check_malloc_state();
- MALLOC_FAILURE_ACTION;
- return 0;
-#endif
- }
-}
-
-/*
- ------------------------------ memalign ------------------------------
-*/
-
-#if __STD_C
-Void_t* mEMALIGn(size_t alignment, size_t bytes)
-#else
-Void_t* mEMALIGn(alignment, bytes) size_t alignment; size_t bytes;
-#endif
-{
- INTERNAL_SIZE_T nb; /* padded request size */
- char* m; /* memory returned by malloc call */
- mchunkptr p; /* corresponding chunk */
- char* brk; /* alignment point within p */
- mchunkptr newp; /* chunk to return */
- INTERNAL_SIZE_T newsize; /* its size */
- INTERNAL_SIZE_T leadsize; /* leading space before alignment point */
- mchunkptr remainder; /* spare room at end to split off */
- CHUNK_SIZE_T remainder_size; /* its size */
- INTERNAL_SIZE_T size;
-
- /* If need less alignment than we give anyway, just relay to malloc */
-
- if (alignment <= MALLOC_ALIGNMENT) return mALLOc(bytes);
-
- /* Otherwise, ensure that it is at least a minimum chunk size */
-
- if (alignment < MINSIZE) alignment = MINSIZE;
-
- /* Make sure alignment is power of 2 (in case MINSIZE is not). */
- if ((alignment & (alignment - 1)) != 0) {
- size_t a = MALLOC_ALIGNMENT * 2;
- while ((CHUNK_SIZE_T)a < (CHUNK_SIZE_T)alignment) a <<= 1;
- alignment = a;
- }
-
- checked_request2size(bytes, nb);
-
- /*
- Strategy: find a spot within that chunk that meets the alignment
- request, and then possibly free the leading and trailing space.
- */
-
-
- /* Call malloc with worst case padding to hit alignment. */
-
- m = (char*)(mALLOc(nb + alignment + MINSIZE));
-
- if (m == 0) return 0; /* propagate failure */
-
- p = mem2chunk(m);
-
- if ((((PTR_UINT)(m)) % alignment) != 0) { /* misaligned */
-
- /*
- Find an aligned spot inside chunk. Since we need to give back
- leading space in a chunk of at least MINSIZE, if the first
- calculation places us at a spot with less than MINSIZE leader,
- we can move to the next aligned spot -- we've allocated enough
- total room so that this is always possible.
- */
-
- brk = (char*)mem2chunk((PTR_UINT)(((PTR_UINT)(m + alignment - 1)) &
- -((signed long) alignment)));
- if ((CHUNK_SIZE_T)(brk - (char*)(p)) < MINSIZE)
- brk += alignment;
-
- newp = (mchunkptr)brk;
- leadsize = brk - (char*)(p);
- newsize = chunksize(p) - leadsize;
-
- /* For mmapped chunks, just adjust offset */
- if (chunk_is_mmapped(p)) {
- newp->prev_size = p->prev_size + leadsize;
- set_head(newp, newsize|IS_MMAPPED);
- return chunk2mem(newp);
- }
-
- /* Otherwise, give back leader, use the rest */
- set_head(newp, newsize | PREV_INUSE);
- set_inuse_bit_at_offset(newp, newsize);
- set_head_size(p, leadsize);
- fREe(chunk2mem(p));
- p = newp;
-
- assert (newsize >= nb &&
- (((PTR_UINT)(chunk2mem(p))) % alignment) == 0);
- }
-
- /* Also give back spare room at the end */
- if (!chunk_is_mmapped(p)) {
- size = chunksize(p);
- if ((CHUNK_SIZE_T)(size) > (CHUNK_SIZE_T)(nb + MINSIZE)) {
- remainder_size = size - nb;
- remainder = chunk_at_offset(p, nb);
- set_head(remainder, remainder_size | PREV_INUSE);
- set_head_size(p, nb);
- fREe(chunk2mem(remainder));
- }
- }
-
- check_inuse_chunk(p);
- return chunk2mem(p);
-}
-
-/*
- ------------------------------ calloc ------------------------------
-*/
-
-#if __STD_C
-Void_t* cALLOc(size_t n_elements, size_t elem_size)
-#else
-Void_t* cALLOc(n_elements, elem_size) size_t n_elements; size_t elem_size;
-#endif
-{
- mchunkptr p;
- CHUNK_SIZE_T clearsize;
- CHUNK_SIZE_T nclears;
- INTERNAL_SIZE_T* d;
-
- Void_t* mem = mALLOc(n_elements * elem_size);
-
- if (mem != 0) {
- p = mem2chunk(mem);
-
- if (!chunk_is_mmapped(p))
- {
- /*
- Unroll clear of <= 36 bytes (72 if 8byte sizes)
- We know that contents have an odd number of
- INTERNAL_SIZE_T-sized words; minimally 3.
- */
-
- d = (INTERNAL_SIZE_T*)mem;
- clearsize = chunksize(p) - SIZE_SZ;
- nclears = clearsize / sizeof(INTERNAL_SIZE_T);
- assert(nclears >= 3);
-
- if (nclears > 9)
- MALLOC_ZERO(d, clearsize);
-
- else {
- *(d+0) = 0;
- *(d+1) = 0;
- *(d+2) = 0;
- if (nclears > 4) {
- *(d+3) = 0;
- *(d+4) = 0;
- if (nclears > 6) {
- *(d+5) = 0;
- *(d+6) = 0;
- if (nclears > 8) {
- *(d+7) = 0;
- *(d+8) = 0;
- }
- }
- }
- }
- }
-#if ! MMAP_CLEARS
- else
- {
- d = (INTERNAL_SIZE_T*)mem;
- /*
- Note the additional SIZE_SZ
- */
- clearsize = chunksize(p) - 2*SIZE_SZ;
- MALLOC_ZERO(d, clearsize);
- }
-#endif
- }
- return mem;
-}
-
-/*
- ------------------------------ cfree ------------------------------
-*/
-
-#if __STD_C
-void cFREe(Void_t *mem)
-#else
-void cFREe(mem) Void_t *mem;
-#endif
-{
- fREe(mem);
-}
-
-#ifdef NEED_INDEPENDENT
-/*
- ------------------------- independent_calloc -------------------------
-*/
-
-#if __STD_C
-Void_t** iCALLOc(size_t n_elements, size_t elem_size, Void_t* chunks[])
-#else
-Void_t** iCALLOc(n_elements, elem_size, chunks) size_t n_elements; size_t elem_size; Void_t* chunks[];
-#endif
-{
- size_t sz = elem_size; /* serves as 1-element array */
- /* opts arg of 3 means all elements are same size, and should be cleared */
- return iALLOc(n_elements, &sz, 3, chunks);
-}
-
-/*
- ------------------------- independent_comalloc -------------------------
-*/
-
-#if __STD_C
-Void_t** iCOMALLOc(size_t n_elements, size_t sizes[], Void_t* chunks[])
-#else
-Void_t** iCOMALLOc(n_elements, sizes, chunks) size_t n_elements; size_t sizes[]; Void_t* chunks[];
-#endif
-{
- return iALLOc(n_elements, sizes, 0, chunks);
-}
-
-/*
- ------------------------------ ialloc ------------------------------
- ialloc provides common support for independent_X routines, handling all of
- the combinations that can result.
-
- The opts arg has:
- bit 0 set if all elements are same size (using sizes[0])
- bit 1 set if elements should be zeroed
-*/
-
-
-#if __STD_C
-static Void_t** iALLOc(size_t n_elements,
- size_t* sizes,
- int opts,
- Void_t* chunks[])
-#else
-static Void_t** iALLOc(n_elements, sizes, opts, chunks) size_t n_elements; size_t* sizes; int opts; Void_t* chunks[];
-#endif
-{
- mstate av = get_malloc_state();
- INTERNAL_SIZE_T element_size; /* chunksize of each element, if all same */
- INTERNAL_SIZE_T contents_size; /* total size of elements */
- INTERNAL_SIZE_T array_size; /* request size of pointer array */
- Void_t* mem; /* malloced aggregate space */
- mchunkptr p; /* corresponding chunk */
- INTERNAL_SIZE_T remainder_size; /* remaining bytes while splitting */
- Void_t** marray; /* either "chunks" or malloced ptr array */
- mchunkptr array_chunk; /* chunk for malloced ptr array */
- int mmx; /* to disable mmap */
- INTERNAL_SIZE_T size;
- size_t i;
-
- /* Ensure initialization */
- if (av->max_fast == 0) malloc_consolidate(av);
-
- /* compute array length, if needed */
- if (chunks != 0) {
- if (n_elements == 0)
- return chunks; /* nothing to do */
- marray = chunks;
- array_size = 0;
- }
- else {
- /* if empty req, must still return chunk representing empty array */
- if (n_elements == 0)
- return (Void_t**) mALLOc(0);
- marray = 0;
- array_size = request2size(n_elements * (sizeof(Void_t*)));
- }
-
- /* compute total element size */
- if (opts & 0x1) { /* all-same-size */
- element_size = request2size(*sizes);
- contents_size = n_elements * element_size;
- }
- else { /* add up all the sizes */
- element_size = 0;
- contents_size = 0;
- for (i = 0; i != n_elements; ++i)
- contents_size += request2size(sizes[i]);
- }
-
- /* subtract out alignment bytes from total to minimize overallocation */
- size = contents_size + array_size - MALLOC_ALIGN_MASK;
-
- /*
- Allocate the aggregate chunk.
- But first disable mmap so malloc won't use it, since
- we would not be able to later free/realloc space internal
- to a segregated mmap region.
- */
- mmx = av->n_mmaps_max; /* disable mmap */
- av->n_mmaps_max = 0;
- mem = mALLOc(size);
- av->n_mmaps_max = mmx; /* reset mmap */
- if (mem == 0)
- return 0;
-
- p = mem2chunk(mem);
- assert(!chunk_is_mmapped(p));
- remainder_size = chunksize(p);
-
- if (opts & 0x2) { /* optionally clear the elements */
- MALLOC_ZERO(mem, remainder_size - SIZE_SZ - array_size);
- }
-
- /* If not provided, allocate the pointer array as final part of chunk */
- if (marray == 0) {
- array_chunk = chunk_at_offset(p, contents_size);
- marray = (Void_t**) (chunk2mem(array_chunk));
- set_head(array_chunk, (remainder_size - contents_size) | PREV_INUSE);
- remainder_size = contents_size;
- }
-
- /* split out elements */
- for (i = 0; ; ++i) {
- marray[i] = chunk2mem(p);
- if (i != n_elements-1) {
- if (element_size != 0)
- size = element_size;
- else
- size = request2size(sizes[i]);
- remainder_size -= size;
- set_head(p, size | PREV_INUSE);
- p = chunk_at_offset(p, size);
- }
- else { /* the final element absorbs any overallocation slop */
- set_head(p, remainder_size | PREV_INUSE);
- break;
- }
- }
-
-#if DEBUG
- if (marray != chunks) {
- /* final element must have exactly exhausted chunk */
- if (element_size != 0)
- assert(remainder_size == element_size);
- else
- assert(remainder_size == request2size(sizes[i]));
- check_inuse_chunk(mem2chunk(marray));
- }
-
- for (i = 0; i != n_elements; ++i)
- check_inuse_chunk(mem2chunk(marray[i]));
-#endif
-
- return marray;
-}
-#endif /* NEED_INDEPENDENT */
-
-
-/*
- ------------------------------ valloc ------------------------------
-*/
-
-#if __STD_C
-Void_t* vALLOc(size_t bytes)
-#else
-Void_t* vALLOc(bytes) size_t bytes;
-#endif
-{
- /* Ensure initialization */
- mstate av = get_malloc_state();
- if (av->max_fast == 0) malloc_consolidate(av);
- return mEMALIGn(av->pagesize, bytes);
-}
-
-#ifdef NEED_PVALLOC
-/*
- ------------------------------ pvalloc ------------------------------
-*/
-
-
-#if __STD_C
-Void_t* pVALLOc(size_t bytes)
-#else
-Void_t* pVALLOc(bytes) size_t bytes;
-#endif
-{
- mstate av = get_malloc_state();
- size_t pagesz;
-
- /* Ensure initialization */
- if (av->max_fast == 0) malloc_consolidate(av);
- pagesz = av->pagesize;
- return mEMALIGn(pagesz, (bytes + pagesz - 1) & ~(pagesz - 1));
-}
-#endif /*NEED_PVALLOC*/
-
-
-/*
- ------------------------------ malloc_trim ------------------------------
-*/
-
-#if __STD_C
-int mTRIm(size_t pad)
-#else
-int mTRIm(pad) size_t pad;
-#endif
-{
- mstate av = get_malloc_state();
- /* Ensure initialization/consolidation */
- malloc_consolidate(av);
-
-#ifndef MORECORE_CANNOT_TRIM
- return sYSTRIm(pad, av);
-#else
- return 0;
-#endif
-}
-
-
-/*
- ------------------------- malloc_usable_size -------------------------
-*/
-
-#if __STD_C
-size_t mUSABLe(Void_t* mem)
-#else
-size_t mUSABLe(mem) Void_t* mem;
-#endif
-{
- mchunkptr p;
- if (mem != 0) {
- p = mem2chunk(mem);
- if (chunk_is_mmapped(p))
- return chunksize(p) - 2*SIZE_SZ;
- else if (inuse(p))
- return chunksize(p) - SIZE_SZ;
- }
- return 0;
-}
-
-/*
- ------------------------------ mallinfo ------------------------------
-*/
-
-struct mallinfo mALLINFo()
-{
- mstate av = get_malloc_state();
- struct mallinfo mi;
- unsigned i;
- mbinptr b;
- mchunkptr p;
- INTERNAL_SIZE_T avail;
- INTERNAL_SIZE_T fastavail;
- int nblocks;
- int nfastblocks;
-
- /* Ensure initialization */
- if (av->top == 0) malloc_consolidate(av);
-
- check_malloc_state();
-
- /* Account for top */
- avail = chunksize(av->top);
- nblocks = 1; /* top always exists */
-
- /* traverse fastbins */
- nfastblocks = 0;
- fastavail = 0;
-
- for (i = 0; i < NFASTBINS; ++i) {
- for (p = av->fastbins[i]; p != 0; p = p->fd) {
- ++nfastblocks;
- fastavail += chunksize(p);
- }
- }
-
- avail += fastavail;
-
- /* traverse regular bins */
- for (i = 1; i < NBINS; ++i) {
- b = bin_at(av, i);
- for (p = last(b); p != b; p = p->bk) {
- ++nblocks;
- avail += chunksize(p);
- }
- }
-
- mi.smblks = nfastblocks;
- mi.ordblks = nblocks;
- mi.fordblks = avail;
- mi.uordblks = av->sbrked_mem - avail;
- mi.arena = av->sbrked_mem;
- mi.hblks = av->n_mmaps;
- mi.hblkhd = av->mmapped_mem;
- mi.fsmblks = fastavail;
- mi.keepcost = chunksize(av->top);
- mi.usmblks = av->max_total_mem;
- return mi;
-}
-
-/*
- ------------------------------ malloc_stats ------------------------------
-*/
-
-void mSTATs()
-{
- struct mallinfo mi = mALLINFo();
-
-#ifdef WIN32
- {
- CHUNK_SIZE_T free, reserved, committed;
- vminfo (&free, &reserved, &committed);
- fprintf(stderr, "free bytes = %10lu\n",
- free);
- fprintf(stderr, "reserved bytes = %10lu\n",
- reserved);
- fprintf(stderr, "committed bytes = %10lu\n",
- committed);
- }
-#endif
-
-
- fprintf(stderr, "max system bytes = %10lu\n",
- (CHUNK_SIZE_T)(mi.usmblks));
- fprintf(stderr, "system bytes = %10lu\n",
- (CHUNK_SIZE_T)(mi.arena + mi.hblkhd));
- fprintf(stderr, "in use bytes = %10lu\n",
- (CHUNK_SIZE_T)(mi.uordblks + mi.hblkhd));
-
-#ifdef WIN32
- {
- CHUNK_SIZE_T kernel, user;
- if (cpuinfo (TRUE, &kernel, &user)) {
- fprintf(stderr, "kernel ms = %10lu\n",
- kernel);
- fprintf(stderr, "user ms = %10lu\n",
- user);
- }
- }
-#endif
-}
-
-
-/*
- ------------------------------ mallopt ------------------------------
-*/
-
-#if __STD_C
-int mALLOPt(int param_number, int value)
-#else
-int mALLOPt(param_number, value) int param_number; int value;
-#endif
-{
- mstate av = get_malloc_state();
- /* Ensure initialization/consolidation */
- malloc_consolidate(av);
-
- switch(param_number) {
- case M_MXFAST:
- if (value >= 0 && value <= MAX_FAST_SIZE) {
- set_max_fast(av, value);
- return 1;
- }
- else
- return 0;
-
- case M_TRIM_THRESHOLD:
- av->trim_threshold = value;
- return 1;
-
- case M_TOP_PAD:
- av->top_pad = value;
- return 1;
-
- case M_MMAP_THRESHOLD:
- av->mmap_threshold = value;
- return 1;
-
- case M_MMAP_MAX:
-#if !HAVE_MMAP
- if (value != 0)
- return 0;
-#endif
- av->n_mmaps_max = value;
- return 1;
-
- default:
- return 0;
- }
-}
-
-/*
- -------------------- Alternative MORECORE functions --------------------
-*/
-
-
-/*
- General Requirements for MORECORE.
-
- The MORECORE function must have the following properties:
-
- If MORECORE_CONTIGUOUS is false:
-
- * MORECORE must allocate in multiples of pagesize. It will
- only be called with arguments that are multiples of pagesize.
-
- * MORECORE(0) must return an address that is at least
- MALLOC_ALIGNMENT aligned. (Page-aligning always suffices.)
-
- else (i.e. If MORECORE_CONTIGUOUS is true):
-
- * Consecutive calls to MORECORE with positive arguments
- return increasing addresses, indicating that space has been
- contiguously extended.
-
- * MORECORE need not allocate in multiples of pagesize.
- Calls to MORECORE need not have args of multiples of pagesize.
-
- * MORECORE need not page-align.
-
- In either case:
-
- * MORECORE may allocate more memory than requested. (Or even less,
- but this will generally result in a malloc failure.)
-
- * MORECORE must not allocate memory when given argument zero, but
- instead return one past the end address of memory from previous
- nonzero call. This malloc does NOT call MORECORE(0)
- until at least one call with positive arguments is made, so
- the initial value returned is not important.
-
- * Even though consecutive calls to MORECORE need not return contiguous
- addresses, it must be OK for malloc'ed chunks to span multiple
- regions in those cases where they do happen to be contiguous.
-
- * MORECORE need not handle negative arguments -- it may instead
- just return MORECORE_FAILURE when given negative arguments.
- Negative arguments are always multiples of pagesize. MORECORE
- must not misinterpret negative args as large positive unsigned
- args. You can suppress all such calls from even occurring by defining
- MORECORE_CANNOT_TRIM,
-
- There is some variation across systems about the type of the
- argument to sbrk/MORECORE. If size_t is unsigned, then it cannot
- actually be size_t, because sbrk supports negative args, so it is
- normally the signed type of the same width as size_t (sometimes
- declared as "intptr_t", and sometimes "ptrdiff_t"). It doesn't much
- matter though. Internally, we use "long" as arguments, which should
- work across all reasonable possibilities.
-
- Additionally, if MORECORE ever returns failure for a positive
- request, and HAVE_MMAP is true, then mmap is used as a noncontiguous
- system allocator. This is a useful backup strategy for systems with
- holes in address spaces -- in this case sbrk cannot contiguously
- expand the heap, but mmap may be able to map noncontiguous space.
-
- If you'd like mmap to ALWAYS be used, you can define MORECORE to be
- a function that always returns MORECORE_FAILURE.
-
- Malloc only has limited ability to detect failures of MORECORE
- to supply contiguous space when it says it can. In particular,
- multithreaded programs that do not use locks may result in
- rece conditions across calls to MORECORE that result in gaps
- that cannot be detected as such, and subsequent corruption.
-
- If you are using this malloc with something other than sbrk (or its
- emulation) to supply memory regions, you probably want to set
- MORECORE_CONTIGUOUS as false. As an example, here is a custom
- allocator kindly contributed for pre-OSX macOS. It uses virtually
- but not necessarily physically contiguous non-paged memory (locked
- in, present and won't get swapped out). You can use it by
- uncommenting this section, adding some #includes, and setting up the
- appropriate defines above:
-
- #define MORECORE osMoreCore
- #define MORECORE_CONTIGUOUS 0
-
- There is also a shutdown routine that should somehow be called for
- cleanup upon program exit.
-
- #define MAX_POOL_ENTRIES 100
- #define MINIMUM_MORECORE_SIZE (64 * 1024)
- static int next_os_pool;
- void *our_os_pools[MAX_POOL_ENTRIES];
-
- void *osMoreCore(int size)
- {
- void *ptr = 0;
- static void *sbrk_top = 0;
-
- if (size > 0)
- {
- if (size < MINIMUM_MORECORE_SIZE)
- size = MINIMUM_MORECORE_SIZE;
- if (CurrentExecutionLevel() == kTaskLevel)
- ptr = PoolAllocateResident(size + RM_PAGE_SIZE, 0);
- if (ptr == 0)
- {
- return (void *) MORECORE_FAILURE;
- }
- // save ptrs so they can be freed during cleanup
- our_os_pools[next_os_pool] = ptr;
- next_os_pool++;
- ptr = (void *) ((((CHUNK_SIZE_T) ptr) + RM_PAGE_MASK) & ~RM_PAGE_MASK);
- sbrk_top = (char *) ptr + size;
- return ptr;
- }
- else if (size < 0)
- {
- // we don't currently support shrink behavior
- return (void *) MORECORE_FAILURE;
- }
- else
- {
- return sbrk_top;
- }
- }
-
- // cleanup any allocated memory pools
- // called as last thing before shutting down driver
-
- void osCleanupMem(void)
- {
- void **ptr;
-
- for (ptr = our_os_pools; ptr < &our_os_pools[MAX_POOL_ENTRIES]; ptr++)
- if (*ptr)
- {
- PoolDeallocate(*ptr);
- *ptr = 0;
- }
- }
-
-*/
-
-
-/*
- --------------------------------------------------------------
-
- Emulation of sbrk for win32.
- Donated by J. Walter <Walter@GeNeSys-e.de>.
- For additional information about this code, and malloc on Win32, see
- http://www.genesys-e.de/jwalter/
-*/
-
-
-#ifdef WIN32
-
-#ifdef _DEBUG
-/* #define TRACE */
-#endif
-
-/* Support for USE_MALLOC_LOCK */
-#ifdef USE_MALLOC_LOCK
-
-/* Wait for spin lock */
-static int slwait (int *sl) {
- while (InterlockedCompareExchange ((void **) sl, (void *) 1, (void *) 0) != 0)
- Sleep (0);
- return 0;
-}
-
-/* Release spin lock */
-static int slrelease (int *sl) {
- InterlockedExchange (sl, 0);
- return 0;
-}
-
-#ifdef NEEDED
-/* Spin lock for emulation code */
-static int g_sl;
-#endif
-
-#endif /* USE_MALLOC_LOCK */
-
-/* getpagesize for windows */
-static long getpagesize (void) {
- static long g_pagesize = 0;
- if (! g_pagesize) {
- SYSTEM_INFO system_info;
- GetSystemInfo (&system_info);
- g_pagesize = system_info.dwPageSize;
- }
- return g_pagesize;
-}
-static long getregionsize (void) {
- static long g_regionsize = 0;
- if (! g_regionsize) {
- SYSTEM_INFO system_info;
- GetSystemInfo (&system_info);
- g_regionsize = system_info.dwAllocationGranularity;
- }
- return g_regionsize;
-}
-
-/* A region list entry */
-typedef struct _region_list_entry {
- void *top_allocated;
- void *top_committed;
- void *top_reserved;
- long reserve_size;
- struct _region_list_entry *previous;
-} region_list_entry;
-
-/* Allocate and link a region entry in the region list */
-static int region_list_append (region_list_entry **last, void *base_reserved, long reserve_size) {
- region_list_entry *next = HeapAlloc (GetProcessHeap (), 0, sizeof (region_list_entry));
- if (! next)
- return FALSE;
- next->top_allocated = (char *) base_reserved;
- next->top_committed = (char *) base_reserved;
- next->top_reserved = (char *) base_reserved + reserve_size;
- next->reserve_size = reserve_size;
- next->previous = *last;
- *last = next;
- return TRUE;
-}
-/* Free and unlink the last region entry from the region list */
-static int region_list_remove (region_list_entry **last) {
- region_list_entry *previous = (*last)->previous;
- if (! HeapFree (GetProcessHeap (), sizeof (region_list_entry), *last))
- return FALSE;
- *last = previous;
- return TRUE;
-}
-
-#define CEIL(size,to) (((size)+(to)-1)&~((to)-1))
-#define FLOOR(size,to) ((size)&~((to)-1))
-
-#define SBRK_SCALE 0
-/* #define SBRK_SCALE 1 */
-/* #define SBRK_SCALE 2 */
-/* #define SBRK_SCALE 4 */
-
-/* sbrk for windows */
-static void *sbrk (long size) {
- static long g_pagesize, g_my_pagesize;
- static long g_regionsize, g_my_regionsize;
- static region_list_entry *g_last;
- void *result = (void *) MORECORE_FAILURE;
-#ifdef TRACE
- printf ("sbrk %d\n", size);
-#endif
-#if defined (USE_MALLOC_LOCK) && defined (NEEDED)
- /* Wait for spin lock */
- slwait (&g_sl);
-#endif
- /* First time initialization */
- if (! g_pagesize) {
- g_pagesize = getpagesize ();
- g_my_pagesize = g_pagesize << SBRK_SCALE;
- }
- if (! g_regionsize) {
- g_regionsize = getregionsize ();
- g_my_regionsize = g_regionsize << SBRK_SCALE;
- }
- if (! g_last) {
- if (! region_list_append (&g_last, 0, 0))
- goto sbrk_exit;
- }
- /* Assert invariants */
- assert (g_last);
- assert ((char *) g_last->top_reserved - g_last->reserve_size <= (char *) g_last->top_allocated &&
- g_last->top_allocated <= g_last->top_committed);
- assert ((char *) g_last->top_reserved - g_last->reserve_size <= (char *) g_last->top_committed &&
- g_last->top_committed <= g_last->top_reserved &&
- (unsigned) g_last->top_committed % g_pagesize == 0);
- assert ((unsigned) g_last->top_reserved % g_regionsize == 0);
- assert ((unsigned) g_last->reserve_size % g_regionsize == 0);
- /* Allocation requested? */
- if (size >= 0) {
- /* Allocation size is the requested size */
- long allocate_size = size;
- /* Compute the size to commit */
- long to_commit = (char *) g_last->top_allocated + allocate_size - (char *) g_last->top_committed;
- /* Do we reach the commit limit? */
- if (to_commit > 0) {
- /* Round size to commit */
- long commit_size = CEIL (to_commit, g_my_pagesize);
- /* Compute the size to reserve */
- long to_reserve = (char *) g_last->top_committed + commit_size - (char *) g_last->top_reserved;
- /* Do we reach the reserve limit? */
- if (to_reserve > 0) {
- /* Compute the remaining size to commit in the current region */
- long remaining_commit_size = (char *) g_last->top_reserved - (char *) g_last->top_committed;
- if (remaining_commit_size > 0) {
- /* Assert preconditions */
- assert ((unsigned) g_last->top_committed % g_pagesize == 0);
- assert (0 < remaining_commit_size && remaining_commit_size % g_pagesize == 0); {
- /* Commit this */
- void *base_committed = VirtualAlloc (g_last->top_committed, remaining_commit_size,
- MEM_COMMIT, PAGE_READWRITE);
- /* Check returned pointer for consistency */
- if (base_committed != g_last->top_committed)
- goto sbrk_exit;
- /* Assert postconditions */
- assert ((unsigned) base_committed % g_pagesize == 0);
-#ifdef TRACE
- printf ("Commit %p %d\n", base_committed, remaining_commit_size);
-#endif
- /* Adjust the regions commit top */
- g_last->top_committed = (char *) base_committed + remaining_commit_size;
- }
- } {
- /* Now we are going to search and reserve. */
- int contiguous = -1;
- int found = FALSE;
- MEMORY_BASIC_INFORMATION memory_info;
- void *base_reserved;
- long reserve_size;
- do {
- /* Assume contiguous memory */
- contiguous = TRUE;
- /* Round size to reserve */
- reserve_size = CEIL (to_reserve, g_my_regionsize);
- /* Start with the current region's top */
- memory_info.BaseAddress = g_last->top_reserved;
- /* Assert preconditions */
- assert ((unsigned) memory_info.BaseAddress % g_pagesize == 0);
- assert (0 < reserve_size && reserve_size % g_regionsize == 0);
- while (VirtualQuery (memory_info.BaseAddress, &memory_info, sizeof (memory_info))) {
- /* Assert postconditions */
- assert ((unsigned) memory_info.BaseAddress % g_pagesize == 0);
-#ifdef TRACE
- printf ("Query %p %d %s\n", memory_info.BaseAddress, memory_info.RegionSize,
- memory_info.State == MEM_FREE ? "FREE":
- (memory_info.State == MEM_RESERVE ? "RESERVED":
- (memory_info.State == MEM_COMMIT ? "COMMITTED": "?")));
-#endif
- /* Region is free, well aligned and big enough: we are done */
- if (memory_info.State == MEM_FREE &&
- (unsigned) memory_info.BaseAddress % g_regionsize == 0 &&
- memory_info.RegionSize >= (unsigned) reserve_size) {
- found = TRUE;
- break;
- }
- /* From now on we can't get contiguous memory! */
- contiguous = FALSE;
- /* Recompute size to reserve */
- reserve_size = CEIL (allocate_size, g_my_regionsize);
- memory_info.BaseAddress = (char *) memory_info.BaseAddress + memory_info.RegionSize;
- /* Assert preconditions */
- assert ((unsigned) memory_info.BaseAddress % g_pagesize == 0);
- assert (0 < reserve_size && reserve_size % g_regionsize == 0);
- }
- /* Search failed? */
- if (! found)
- goto sbrk_exit;
- /* Assert preconditions */
- assert ((unsigned) memory_info.BaseAddress % g_regionsize == 0);
- assert (0 < reserve_size && reserve_size % g_regionsize == 0);
- /* Try to reserve this */
- base_reserved = VirtualAlloc (memory_info.BaseAddress, reserve_size,
- MEM_RESERVE, PAGE_NOACCESS);
- if (! base_reserved) {
- int rc = GetLastError ();
- if (rc != ERROR_INVALID_ADDRESS)
- goto sbrk_exit;
- }
- /* A null pointer signals (hopefully) a race condition with another thread. */
- /* In this case, we try again. */
- } while (! base_reserved);
- /* Check returned pointer for consistency */
- if (memory_info.BaseAddress && base_reserved != memory_info.BaseAddress)
- goto sbrk_exit;
- /* Assert postconditions */
- assert ((unsigned) base_reserved % g_regionsize == 0);
-#ifdef TRACE
- printf ("Reserve %p %d\n", base_reserved, reserve_size);
-#endif
- /* Did we get contiguous memory? */
- if (contiguous) {
- long start_size = (char *) g_last->top_committed - (char *) g_last->top_allocated;
- /* Adjust allocation size */
- allocate_size -= start_size;
- /* Adjust the regions allocation top */
- g_last->top_allocated = g_last->top_committed;
- /* Recompute the size to commit */
- to_commit = (char *) g_last->top_allocated + allocate_size - (char *) g_last->top_committed;
- /* Round size to commit */
- commit_size = CEIL (to_commit, g_my_pagesize);
- }
- /* Append the new region to the list */
- if (! region_list_append (&g_last, base_reserved, reserve_size))
- goto sbrk_exit;
- /* Didn't we get contiguous memory? */
- if (! contiguous) {
- /* Recompute the size to commit */
- to_commit = (char *) g_last->top_allocated + allocate_size - (char *) g_last->top_committed;
- /* Round size to commit */
- commit_size = CEIL (to_commit, g_my_pagesize);
- }
- }
- }
- /* Assert preconditions */
- assert ((unsigned) g_last->top_committed % g_pagesize == 0);
- assert (0 < commit_size && commit_size % g_pagesize == 0); {
- /* Commit this */
- void *base_committed = VirtualAlloc (g_last->top_committed, commit_size,
- MEM_COMMIT, PAGE_READWRITE);
- /* Check returned pointer for consistency */
- if (base_committed != g_last->top_committed)
- goto sbrk_exit;
- /* Assert postconditions */
- assert ((unsigned) base_committed % g_pagesize == 0);
-#ifdef TRACE
- printf ("Commit %p %d\n", base_committed, commit_size);
-#endif
- /* Adjust the regions commit top */
- g_last->top_committed = (char *) base_committed + commit_size;
- }
- }
- /* Adjust the regions allocation top */
- g_last->top_allocated = (char *) g_last->top_allocated + allocate_size;
- result = (char *) g_last->top_allocated - size;
- /* Deallocation requested? */
- } else if (size < 0) {
- long deallocate_size = - size;
- /* As long as we have a region to release */
- while ((char *) g_last->top_allocated - deallocate_size < (char *) g_last->top_reserved - g_last->reserve_size) {
- /* Get the size to release */
- long release_size = g_last->reserve_size;
- /* Get the base address */
- void *base_reserved = (char *) g_last->top_reserved - release_size;
- /* Assert preconditions */
- assert ((unsigned) base_reserved % g_regionsize == 0);
- assert (0 < release_size && release_size % g_regionsize == 0); {
- /* Release this */
- int rc = VirtualFree (base_reserved, 0,
- MEM_RELEASE);
- /* Check returned code for consistency */
- if (! rc)
- goto sbrk_exit;
-#ifdef TRACE
- printf ("Release %p %d\n", base_reserved, release_size);
-#endif
- }
- /* Adjust deallocation size */
- deallocate_size -= (char *) g_last->top_allocated - (char *) base_reserved;
- /* Remove the old region from the list */
- if (! region_list_remove (&g_last))
- goto sbrk_exit;
- } {
- /* Compute the size to decommit */
- long to_decommit = (char *) g_last->top_committed - ((char *) g_last->top_allocated - deallocate_size);
- if (to_decommit >= g_my_pagesize) {
- /* Compute the size to decommit */
- long decommit_size = FLOOR (to_decommit, g_my_pagesize);
- /* Compute the base address */
- void *base_committed = (char *) g_last->top_committed - decommit_size;
- /* Assert preconditions */
- assert ((unsigned) base_committed % g_pagesize == 0);
- assert (0 < decommit_size && decommit_size % g_pagesize == 0); {
- /* Decommit this */
- int rc = VirtualFree ((char *) base_committed, decommit_size,
- MEM_DECOMMIT);
- /* Check returned code for consistency */
- if (! rc)
- goto sbrk_exit;
-#ifdef TRACE
- printf ("Decommit %p %d\n", base_committed, decommit_size);
-#endif
- }
- /* Adjust deallocation size and regions commit and allocate top */
- deallocate_size -= (char *) g_last->top_allocated - (char *) base_committed;
- g_last->top_committed = base_committed;
- g_last->top_allocated = base_committed;
- }
- }
- /* Adjust regions allocate top */
- g_last->top_allocated = (char *) g_last->top_allocated - deallocate_size;
- /* Check for underflow */
- if ((char *) g_last->top_reserved - g_last->reserve_size > (char *) g_last->top_allocated ||
- g_last->top_allocated > g_last->top_committed) {
- /* Adjust regions allocate top */
- g_last->top_allocated = (char *) g_last->top_reserved - g_last->reserve_size;
- goto sbrk_exit;
- }
- result = g_last->top_allocated;
- }
- /* Assert invariants */
- assert (g_last);
- assert ((char *) g_last->top_reserved - g_last->reserve_size <= (char *) g_last->top_allocated &&
- g_last->top_allocated <= g_last->top_committed);
- assert ((char *) g_last->top_reserved - g_last->reserve_size <= (char *) g_last->top_committed &&
- g_last->top_committed <= g_last->top_reserved &&
- (unsigned) g_last->top_committed % g_pagesize == 0);
- assert ((unsigned) g_last->top_reserved % g_regionsize == 0);
- assert ((unsigned) g_last->reserve_size % g_regionsize == 0);
-
-sbrk_exit:
-#if defined (USE_MALLOC_LOCK) && defined (NEEDED)
- /* Release spin lock */
- slrelease (&g_sl);
-#endif
- return result;
-}
-
-/* mmap for windows */
-static void *mmap (void *ptr, long size, long prot, long type, long handle, long arg) {
- static long g_pagesize;
- static long g_regionsize;
-#ifdef TRACE
- printf ("mmap %d\n", size);
-#endif
-#if defined (USE_MALLOC_LOCK) && defined (NEEDED)
- /* Wait for spin lock */
- slwait (&g_sl);
-#endif
- /* First time initialization */
- if (! g_pagesize)
- g_pagesize = getpagesize ();
- if (! g_regionsize)
- g_regionsize = getregionsize ();
- /* Assert preconditions */
- assert ((unsigned) ptr % g_regionsize == 0);
- assert (size % g_pagesize == 0);
- /* Allocate this */
- ptr = VirtualAlloc (ptr, size,
- MEM_RESERVE | MEM_COMMIT | MEM_TOP_DOWN, PAGE_READWRITE);
- if (! ptr) {
- ptr = (void *) MORECORE_FAILURE;
- goto mmap_exit;
- }
- /* Assert postconditions */
- assert ((unsigned) ptr % g_regionsize == 0);
-#ifdef TRACE
- printf ("Commit %p %d\n", ptr, size);
-#endif
-mmap_exit:
-#if defined (USE_MALLOC_LOCK) && defined (NEEDED)
- /* Release spin lock */
- slrelease (&g_sl);
-#endif
- return ptr;
-}
-
-/* munmap for windows */
-static long munmap (void *ptr, long size) {
- static long g_pagesize;
- static long g_regionsize;
- int rc = MUNMAP_FAILURE;
-#ifdef TRACE
- printf ("munmap %p %d\n", ptr, size);
-#endif
-#if defined (USE_MALLOC_LOCK) && defined (NEEDED)
- /* Wait for spin lock */
- slwait (&g_sl);
-#endif
- /* First time initialization */
- if (! g_pagesize)
- g_pagesize = getpagesize ();
- if (! g_regionsize)
- g_regionsize = getregionsize ();
- /* Assert preconditions */
- assert ((unsigned) ptr % g_regionsize == 0);
- assert (size % g_pagesize == 0);
- /* Free this */
- if (! VirtualFree (ptr, 0,
- MEM_RELEASE))
- goto munmap_exit;
- rc = 0;
-#ifdef TRACE
- printf ("Release %p %d\n", ptr, size);
-#endif
-munmap_exit:
-#if defined (USE_MALLOC_LOCK) && defined (NEEDED)
- /* Release spin lock */
- slrelease (&g_sl);
-#endif
- return rc;
-}
-
-static void vminfo (CHUNK_SIZE_T *free, CHUNK_SIZE_T *reserved, CHUNK_SIZE_T *committed) {
- MEMORY_BASIC_INFORMATION memory_info;
- memory_info.BaseAddress = 0;
- *free = *reserved = *committed = 0;
- while (VirtualQuery (memory_info.BaseAddress, &memory_info, sizeof (memory_info))) {
- switch (memory_info.State) {
- case MEM_FREE:
- *free += memory_info.RegionSize;
- break;
- case MEM_RESERVE:
- *reserved += memory_info.RegionSize;
- break;
- case MEM_COMMIT:
- *committed += memory_info.RegionSize;
- break;
- }
- memory_info.BaseAddress = (char *) memory_info.BaseAddress + memory_info.RegionSize;
- }
-}
-
-static int cpuinfo (int whole, CHUNK_SIZE_T *kernel, CHUNK_SIZE_T *user) {
- if (whole) {
- __int64 creation64, exit64, kernel64, user64;
- int rc = GetProcessTimes (GetCurrentProcess (),
- (FILETIME *) &creation64,
- (FILETIME *) &exit64,
- (FILETIME *) &kernel64,
- (FILETIME *) &user64);
- if (! rc) {
- *kernel = 0;
- *user = 0;
- return FALSE;
- }
- *kernel = (CHUNK_SIZE_T) (kernel64 / 10000);
- *user = (CHUNK_SIZE_T) (user64 / 10000);
- return TRUE;
- } else {
- __int64 creation64, exit64, kernel64, user64;
- int rc = GetThreadTimes (GetCurrentThread (),
- (FILETIME *) &creation64,
- (FILETIME *) &exit64,
- (FILETIME *) &kernel64,
- (FILETIME *) &user64);
- if (! rc) {
- *kernel = 0;
- *user = 0;
- return FALSE;
- }
- *kernel = (CHUNK_SIZE_T) (kernel64 / 10000);
- *user = (CHUNK_SIZE_T) (user64 / 10000);
- return TRUE;
- }
-}
-
-#endif /* WIN32 */
-
-/* ------------------------------------------------------------
-History:
- V2.7.2 Sat Aug 17 09:07:30 2002 Doug Lea (dl at gee)
- * Fix malloc_state bitmap array misdeclaration
-
- V2.7.1 Thu Jul 25 10:58:03 2002 Doug Lea (dl at gee)
- * Allow tuning of FIRST_SORTED_BIN_SIZE
- * Use PTR_UINT as type for all ptr->int casts. Thanks to John Belmonte.
- * Better detection and support for non-contiguousness of MORECORE.
- Thanks to Andreas Mueller, Conal Walsh, and Wolfram Gloger
- * Bypass most of malloc if no frees. Thanks To Emery Berger.
- * Fix freeing of old top non-contiguous chunk im sysmalloc.
- * Raised default trim and map thresholds to 256K.
- * Fix mmap-related #defines. Thanks to Lubos Lunak.
- * Fix copy macros; added LACKS_FCNTL_H. Thanks to Neal Walfield.
- * Branch-free bin calculation
- * Default trim and mmap thresholds now 256K.
-
- V2.7.0 Sun Mar 11 14:14:06 2001 Doug Lea (dl at gee)
- * Introduce independent_comalloc and independent_calloc.
- Thanks to Michael Pachos for motivation and help.
- * Make optional .h file available
- * Allow > 2GB requests on 32bit systems.
- * new WIN32 sbrk, mmap, munmap, lock code from <Walter@GeNeSys-e.de>.
- Thanks also to Andreas Mueller <a.mueller at paradatec.de>,
- and Anonymous.
- * Allow override of MALLOC_ALIGNMENT (Thanks to Ruud Waij for
- helping test this.)
- * memalign: check alignment arg
- * realloc: don't try to shift chunks backwards, since this
- leads to more fragmentation in some programs and doesn't
- seem to help in any others.
- * Collect all cases in malloc requiring system memory into sYSMALLOc
- * Use mmap as backup to sbrk
- * Place all internal state in malloc_state
- * Introduce fastbins (although similar to 2.5.1)
- * Many minor tunings and cosmetic improvements
- * Introduce USE_PUBLIC_MALLOC_WRAPPERS, USE_MALLOC_LOCK
- * Introduce MALLOC_FAILURE_ACTION, MORECORE_CONTIGUOUS
- Thanks to Tony E. Bennett <tbennett@nvidia.com> and others.
- * Include errno.h to support default failure action.
-
- V2.6.6 Sun Dec 5 07:42:19 1999 Doug Lea (dl at gee)
- * return null for negative arguments
- * Added Several WIN32 cleanups from Martin C. Fong <mcfong at yahoo.com>
- * Add 'LACKS_SYS_PARAM_H' for those systems without 'sys/param.h'
- (e.g. WIN32 platforms)
- * Cleanup header file inclusion for WIN32 platforms
- * Cleanup code to avoid Microsoft Visual C++ compiler complaints
- * Add 'USE_DL_PREFIX' to quickly allow co-existence with existing
- memory allocation routines
- * Set 'malloc_getpagesize' for WIN32 platforms (needs more work)
- * Use 'assert' rather than 'ASSERT' in WIN32 code to conform to
- usage of 'assert' in non-WIN32 code
- * Improve WIN32 'sbrk()' emulation's 'findRegion()' routine to
- avoid infinite loop
- * Always call 'fREe()' rather than 'free()'
-
- V2.6.5 Wed Jun 17 15:57:31 1998 Doug Lea (dl at gee)
- * Fixed ordering problem with boundary-stamping
-
- V2.6.3 Sun May 19 08:17:58 1996 Doug Lea (dl at gee)
- * Added pvalloc, as recommended by H.J. Liu
- * Added 64bit pointer support mainly from Wolfram Gloger
- * Added anonymously donated WIN32 sbrk emulation
- * Malloc, calloc, getpagesize: add optimizations from Raymond Nijssen
- * malloc_extend_top: fix mask error that caused wastage after
- foreign sbrks
- * Add linux mremap support code from HJ Liu
-
- V2.6.2 Tue Dec 5 06:52:55 1995 Doug Lea (dl at gee)
- * Integrated most documentation with the code.
- * Add support for mmap, with help from
- Wolfram Gloger (Gloger@lrz.uni-muenchen.de).
- * Use last_remainder in more cases.
- * Pack bins using idea from colin@nyx10.cs.du.edu
- * Use ordered bins instead of best-fit threshhold
- * Eliminate block-local decls to simplify tracing and debugging.
- * Support another case of realloc via move into top
- * Fix error occuring when initial sbrk_base not word-aligned.
- * Rely on page size for units instead of SBRK_UNIT to
- avoid surprises about sbrk alignment conventions.
- * Add mallinfo, mallopt. Thanks to Raymond Nijssen
- (raymond@es.ele.tue.nl) for the suggestion.
- * Add `pad' argument to malloc_trim and top_pad mallopt parameter.
- * More precautions for cases where other routines call sbrk,
- courtesy of Wolfram Gloger (Gloger@lrz.uni-muenchen.de).
- * Added macros etc., allowing use in linux libc from
- H.J. Lu (hjl@gnu.ai.mit.edu)
- * Inverted this history list
-
- V2.6.1 Sat Dec 2 14:10:57 1995 Doug Lea (dl at gee)
- * Re-tuned and fixed to behave more nicely with V2.6.0 changes.
- * Removed all preallocation code since under current scheme
- the work required to undo bad preallocations exceeds
- the work saved in good cases for most test programs.
- * No longer use return list or unconsolidated bins since
- no scheme using them consistently outperforms those that don't
- given above changes.
- * Use best fit for very large chunks to prevent some worst-cases.
- * Added some support for debugging
-
- V2.6.0 Sat Nov 4 07:05:23 1995 Doug Lea (dl at gee)
- * Removed footers when chunks are in use. Thanks to
- Paul Wilson (wilson@cs.texas.edu) for the suggestion.
-
- V2.5.4 Wed Nov 1 07:54:51 1995 Doug Lea (dl at gee)
- * Added malloc_trim, with help from Wolfram Gloger
- (wmglo@Dent.MED.Uni-Muenchen.DE).
-
- V2.5.3 Tue Apr 26 10:16:01 1994 Doug Lea (dl at g)
-
- V2.5.2 Tue Apr 5 16:20:40 1994 Doug Lea (dl at g)
- * realloc: try to expand in both directions
- * malloc: swap order of clean-bin strategy;
- * realloc: only conditionally expand backwards
- * Try not to scavenge used bins
- * Use bin counts as a guide to preallocation
- * Occasionally bin return list chunks in first scan
- * Add a few optimizations from colin@nyx10.cs.du.edu
-
- V2.5.1 Sat Aug 14 15:40:43 1993 Doug Lea (dl at g)
- * faster bin computation & slightly different binning
- * merged all consolidations to one part of malloc proper
- (eliminating old malloc_find_space & malloc_clean_bin)
- * Scan 2 returns chunks (not just 1)
- * Propagate failure in realloc if malloc returns 0
- * Add stuff to allow compilation on non-ANSI compilers
- from kpv@research.att.com
-
- V2.5 Sat Aug 7 07:41:59 1993 Doug Lea (dl at g.oswego.edu)
- * removed potential for odd address access in prev_chunk
- * removed dependency on getpagesize.h
- * misc cosmetics and a bit more internal documentation
- * anticosmetics: mangled names in macros to evade debugger strangeness
- * tested on sparc, hp-700, dec-mips, rs6000
- with gcc & native cc (hp, dec only) allowing
- Detlefs & Zorn comparison study (in SIGPLAN Notices.)
-
- Trial version Fri Aug 28 13:14:29 1992 Doug Lea (dl at g.oswego.edu)
- * Based loosely on libg++-1.2X malloc. (It retains some of the overall
- structure of old version, but most details differ.)
-
-*/