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Diffstat (limited to 'include/gdb/callback.h')
| -rw-r--r-- | include/gdb/callback.h | 279 |
1 files changed, 279 insertions, 0 deletions
diff --git a/include/gdb/callback.h b/include/gdb/callback.h new file mode 100644 index 000000000..aa956d05f --- /dev/null +++ b/include/gdb/callback.h @@ -0,0 +1,279 @@ +/* Remote target system call callback support. + Copyright 1997 Free Software Foundation, Inc. + Contributed by Cygnus Solutions. + +This file is part of GDB. + +This program is free software; you can redistribute it and/or modify +it under the terms of the GNU General Public License as published by +the Free Software Foundation; either version 2 of the License, or +(at your option) any later version. + +This program is distributed in the hope that it will be useful, +but WITHOUT ANY WARRANTY; without even the implied warranty of +MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the +GNU General Public License for more details. + +You should have received a copy of the GNU General Public License +along with this program; if not, write to the Free Software +Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA. */ + +/* This interface isn't intended to be specific to any particular kind + of remote (hardware, simulator, whatever). As such, support for it + (e.g. sim/common/callback.c) should *not* live in the simulator source + tree, nor should it live in the gdb source tree. */ + +/* There are various ways to handle system calls: + + 1) Have a simulator intercept the appropriate trap instruction and + directly perform the system call on behalf of the target program. + This is the typical way of handling system calls for embedded targets. + [Handling system calls for embedded targets isn't that much of an + oxymoron as running compiler testsuites make use of the capability.] + + This method of system call handling is done when STATE_ENVIRONMENT + is ENVIRONMENT_USER. + + 2) Have a simulator emulate the hardware as much as possible. + If the program running on the real hardware communicates with some sort + of target manager, one would want to be able to run this program on the + simulator as well. + + This method of system call handling is done when STATE_ENVIRONMENT + is ENVIRONMENT_OPERATING. +*/ + +#ifndef CALLBACK_H +#define CALLBACK_H + +/* ??? The reason why we check for va_start here should be documented. */ + +#ifndef va_start +#include <ansidecl.h> +#ifdef ANSI_PROTOTYPES +#include <stdarg.h> +#else +#include <varargs.h> +#endif +#endif + +/* Mapping of host/target values. */ +/* ??? For debugging purposes, one might want to add a string of the + name of the symbol. */ + +typedef struct { + int host_val; + int target_val; +} CB_TARGET_DEFS_MAP; + +#define MAX_CALLBACK_FDS 10 + +/* Forward decl for stat/fstat. */ +struct stat; + +typedef struct host_callback_struct host_callback; + +struct host_callback_struct +{ + int (*close) PARAMS ((host_callback *,int)); + int (*get_errno) PARAMS ((host_callback *)); + int (*isatty) PARAMS ((host_callback *, int)); + int (*lseek) PARAMS ((host_callback *, int, long , int)); + int (*open) PARAMS ((host_callback *, const char*, int mode)); + int (*read) PARAMS ((host_callback *,int, char *, int)); + int (*read_stdin) PARAMS (( host_callback *, char *, int)); + int (*rename) PARAMS ((host_callback *, const char *, const char *)); + int (*system) PARAMS ((host_callback *, const char *)); + long (*time) PARAMS ((host_callback *, long *)); + int (*unlink) PARAMS ((host_callback *, const char *)); + int (*write) PARAMS ((host_callback *,int, const char *, int)); + int (*write_stdout) PARAMS ((host_callback *, const char *, int)); + void (*flush_stdout) PARAMS ((host_callback *)); + int (*write_stderr) PARAMS ((host_callback *, const char *, int)); + void (*flush_stderr) PARAMS ((host_callback *)); + int (*stat) PARAMS ((host_callback *, const char *, struct stat *)); + int (*fstat) PARAMS ((host_callback *, int, struct stat *)); + int (*ftruncate) PARAMS ((host_callback *, int, long)); + int (*truncate) PARAMS ((host_callback *, const char *, long)); + + /* When present, call to the client to give it the oportunity to + poll any io devices for a request to quit (indicated by a nonzero + return value). */ + int (*poll_quit) PARAMS ((host_callback *)); + + /* Used when the target has gone away, so we can close open + handles and free memory etc etc. */ + int (*shutdown) PARAMS ((host_callback *)); + int (*init) PARAMS ((host_callback *)); + + /* depreciated, use vprintf_filtered - Talk to the user on a console. */ + void (*printf_filtered) PARAMS ((host_callback *, const char *, ...)); + + /* Talk to the user on a console. */ + void (*vprintf_filtered) PARAMS ((host_callback *, const char *, va_list)); + + /* Same as vprintf_filtered but to stderr. */ + void (*evprintf_filtered) PARAMS ((host_callback *, const char *, va_list)); + + /* Print an error message and "exit". + In the case of gdb "exiting" means doing a longjmp back to the main + command loop. */ + void (*error) PARAMS ((host_callback *, const char *, ...)); + + int last_errno; /* host format */ + + int fdmap[MAX_CALLBACK_FDS]; + /* fd_buddy is used to contruct circular lists of target fds that point to + the same host fd. A uniquely mapped fd points to itself; for a closed + one, fd_buddy has the value -1. The host file descriptors for stdin / + stdout / stderr are never closed by the simulators, so they are put + in a special fd_buddy circular list which also has MAX_CALLBACK_FDS + as a member. */ + /* ??? We don't have a callback entry for dup, although it is trival to + implement now. */ + short fd_buddy[MAX_CALLBACK_FDS+1]; + + /* System call numbers. */ + CB_TARGET_DEFS_MAP *syscall_map; + /* Errno values. */ + CB_TARGET_DEFS_MAP *errno_map; + /* Flags to the open system call. */ + CB_TARGET_DEFS_MAP *open_map; + /* Signal numbers. */ + CB_TARGET_DEFS_MAP *signal_map; + /* Layout of `stat' struct. + The format is a series of "name,length" pairs separated by colons. + Empty space is indicated with a `name' of "space". + All padding must be explicitly mentioned. + Lengths are in bytes. If this needs to be extended to bits, + use "name.bits". + Example: "st_dev,4:st_ino,4:st_mode,4:..." */ + const char *stat_map; + + /* Marker for those wanting to do sanity checks. + This should remain the last member of this struct to help catch + miscompilation errors. */ +#define HOST_CALLBACK_MAGIC 4705 /* teds constant */ + int magic; +}; + +extern host_callback default_callback; + +/* Canonical versions of system call numbers. + It's not intended to willy-nilly throw every system call ever heard + of in here. Only include those that have an important use. + ??? One can certainly start a discussion over the ones that are currently + here, but that will always be true. */ + +/* These are used by the ANSI C support of libc. */ +#define CB_SYS_exit 1 +#define CB_SYS_open 2 +#define CB_SYS_close 3 +#define CB_SYS_read 4 +#define CB_SYS_write 5 +#define CB_SYS_lseek 6 +#define CB_SYS_unlink 7 +#define CB_SYS_getpid 8 +#define CB_SYS_kill 9 +#define CB_SYS_fstat 10 +/*#define CB_SYS_sbrk 11 - not currently a system call, but reserved. */ + +/* ARGV support. */ +#define CB_SYS_argvlen 12 +#define CB_SYS_argv 13 + +/* These are extras added for one reason or another. */ +#define CB_SYS_chdir 14 +#define CB_SYS_stat 15 +#define CB_SYS_chmod 16 +#define CB_SYS_utime 17 +#define CB_SYS_time 18 + +/* Struct use to pass and return information necessary to perform a + system call. */ +/* FIXME: Need to consider target word size. */ + +typedef struct cb_syscall { + /* The target's value of what system call to perform. */ + int func; + /* The arguments to the syscall. */ + long arg1, arg2, arg3, arg4; + + /* The result. */ + long result; + /* Some system calls have two results. */ + long result2; + /* The target's errno value, or 0 if success. + This is converted to the target's value with host_to_target_errno. */ + int errcode; + + /* Working space to be used by memory read/write callbacks. */ + PTR p1; + PTR p2; + long x1,x2; + + /* Callbacks for reading/writing memory (e.g. for read/write syscalls). + ??? long or unsigned long might be better to use for the `count' + argument here. We mimic sim_{read,write} for now. Be careful to + test any changes with -Wall -Werror, mixed signed comparisons + will get you. */ + int (*read_mem) PARAMS ((host_callback * /*cb*/, struct cb_syscall * /*sc*/, + unsigned long /*taddr*/, char * /*buf*/, + int /*bytes*/)); + int (*write_mem) PARAMS ((host_callback * /*cb*/, struct cb_syscall * /*sc*/, + unsigned long /*taddr*/, const char * /*buf*/, + int /*bytes*/)); + + /* For sanity checking, should be last entry. */ + int magic; +} CB_SYSCALL; + +/* Magic number sanity checker. */ +#define CB_SYSCALL_MAGIC 0x12344321 + +/* Macro to initialize CB_SYSCALL. Called first, before filling in + any fields. */ +#define CB_SYSCALL_INIT(sc) \ +do { \ + memset ((sc), 0, sizeof (*(sc))); \ + (sc)->magic = CB_SYSCALL_MAGIC; \ +} while (0) + +/* Return codes for various interface routines. */ + +typedef enum { + CB_RC_OK = 0, + /* generic error */ + CB_RC_ERR, + /* either file not found or no read access */ + CB_RC_ACCESS, + CB_RC_NO_MEM +} CB_RC; + +/* Read in target values for system call numbers, errno values, signals. */ +CB_RC cb_read_target_syscall_maps PARAMS ((host_callback *, const char *)); + +/* Translate target to host syscall function numbers. */ +int cb_target_to_host_syscall PARAMS ((host_callback *, int)); + +/* Translate host to target errno value. */ +int cb_host_to_target_errno PARAMS ((host_callback *, int)); + +/* Translate target to host open flags. */ +int cb_target_to_host_open PARAMS ((host_callback *, int)); + +/* Translate target signal number to host. */ +int cb_target_to_host_signal PARAMS ((host_callback *, int)); + +/* Translate host signal number to target. */ +int cb_host_to_target_signal PARAMS ((host_callback *, int)); + +/* Translate host stat struct to target. + If stat struct ptr is NULL, just compute target stat struct size. + Result is size of target stat struct or 0 if error. */ +int cb_host_to_target_stat PARAMS ((host_callback *, const struct stat *, PTR)); + +/* Perform a system call. */ +CB_RC cb_syscall PARAMS ((host_callback *, CB_SYSCALL *)); + +#endif |