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#define _LARGEFILE64_SOURCE
#define _FILE_OFFSET_BITS 64
#include "util/file.hh"
#include "util/exception.hh"
#include <algorithm>
#include <cstdlib>
#include <cstdio>
#include <iostream>
#include <limits>
#include <sstream>
#include <assert.h>
#include <errno.h>
#include <limits.h>
#include <sys/types.h>
#include <sys/stat.h>
#include <fcntl.h>
#include <stdint.h>
#if defined(__MINGW32__)
#include <windows.h>
#include <unistd.h>
#warning "The file functions on MinGW have not been tested for file sizes above 2^31 - 1. Please read https://stackoverflow.com/questions/12539488/determine-64-bit-file-size-in-c-on-mingw-32-bit and fix"
#elif defined(_WIN32) || defined(_WIN64)
#include <windows.h>
#include <io.h>
#else
#include <unistd.h>
#endif
namespace util {
scoped_fd::~scoped_fd() {
if (fd_ != -1 && close(fd_)) {
std::cerr << "Could not close file " << fd_ << std::endl;
std::abort();
}
}
scoped_FILE::~scoped_FILE() {
if (file_ && std::fclose(file_)) {
std::cerr << "Could not close file " << std::endl;
std::abort();
}
}
// Note that ErrnoException records errno before NameFromFD is called.
FDException::FDException(int fd) throw() : fd_(fd), name_guess_(NameFromFD(fd)) {
*this << "in " << name_guess_ << ' ';
}
FDException::~FDException() throw() {}
EndOfFileException::EndOfFileException() throw() {
*this << "End of file";
}
EndOfFileException::~EndOfFileException() throw() {}
int OpenReadOrThrow(const char *name) {
int ret;
#if defined(_WIN32) || defined(_WIN64)
UTIL_THROW_IF(-1 == (ret = _open(name, _O_BINARY | _O_RDONLY)), ErrnoException, "while opening " << name);
#else
UTIL_THROW_IF(-1 == (ret = open(name, O_RDONLY)), ErrnoException, "while opening " << name);
#endif
return ret;
}
int CreateOrThrow(const char *name) {
int ret;
#if defined(_WIN32) || defined(_WIN64)
UTIL_THROW_IF(-1 == (ret = _open(name, _O_CREAT | _O_TRUNC | _O_RDWR | _O_BINARY, _S_IREAD | _S_IWRITE)), ErrnoException, "while creating " << name);
#else
UTIL_THROW_IF(-1 == (ret = open(name, O_CREAT | O_TRUNC | O_RDWR, S_IRUSR | S_IWUSR | S_IRGRP | S_IROTH)), ErrnoException, "while creating " << name);
#endif
return ret;
}
uint64_t SizeFile(int fd) {
#if defined __MINGW32__
struct stat sb;
// Does this handle 64-bit?
int ret = fstat(fd, &sb);
if (ret == -1 || (!sb.st_size && !S_ISREG(sb.st_mode))) return kBadSize;
return sb.st_size;
#elif defined(_WIN32) || defined(_WIN64)
__int64 ret = _filelengthi64(fd);
return (ret == -1) ? kBadSize : ret;
#else // Not windows.
#ifdef OS_ANDROID
struct stat64 sb;
int ret = fstat64(fd, &sb);
#else
struct stat sb;
int ret = fstat(fd, &sb);
#endif
if (ret == -1 || (!sb.st_size && !S_ISREG(sb.st_mode))) return kBadSize;
return sb.st_size;
#endif
}
uint64_t SizeOrThrow(int fd) {
uint64_t ret = SizeFile(fd);
UTIL_THROW_IF_ARG(ret == kBadSize, FDException, (fd), "Failed to size");
return ret;
}
void ResizeOrThrow(int fd, uint64_t to) {
#if defined __MINGW32__
// Does this handle 64-bit?
int ret = ftruncate
#elif defined(_WIN32) || defined(_WIN64)
errno_t ret = _chsize_s
#elif defined(OS_ANDROID)
int ret = ftruncate64
#else
int ret = ftruncate
#endif
(fd, to);
UTIL_THROW_IF_ARG(ret, FDException, (fd), "while resizing to " << to << " bytes");
}
namespace {
std::size_t GuardLarge(std::size_t size) {
// The following operating systems have broken read/write/pread/pwrite that
// only supports up to 2^31.
// OS X man pages claim to support 64-bit, but Kareem M. Darwish had problems
// building with larger files, so APPLE is also here.
#if defined(_WIN32) || defined(_WIN64) || defined(__APPLE__) || defined(OS_ANDROID) || defined(__MINGW32__)
return size < INT_MAX ? size : INT_MAX;
#else
return size;
#endif
}
}
std::size_t PartialRead(int fd, void *to, std::size_t amount) {
#if defined(_WIN32) || defined(_WIN64)
int ret = _read(fd, to, GuardLarge(amount));
#else
errno = 0;
ssize_t ret;
do {
ret = read(fd, to, GuardLarge(amount));
} while (ret == -1 && errno == EINTR);
#endif
UTIL_THROW_IF_ARG(ret < 0, FDException, (fd), "while reading " << amount << " bytes");
return static_cast<std::size_t>(ret);
}
void ReadOrThrow(int fd, void *to_void, std::size_t amount) {
uint8_t *to = static_cast<uint8_t*>(to_void);
while (amount) {
std::size_t ret = PartialRead(fd, to, amount);
UTIL_THROW_IF(ret == 0, EndOfFileException, " in " << NameFromFD(fd) << " but there should be " << amount << " more bytes to read.");
amount -= ret;
to += ret;
}
}
std::size_t ReadOrEOF(int fd, void *to_void, std::size_t amount) {
uint8_t *to = static_cast<uint8_t*>(to_void);
std::size_t remaining = amount;
while (remaining) {
std::size_t ret = PartialRead(fd, to, remaining);
if (!ret) return amount - remaining;
remaining -= ret;
to += ret;
}
return amount;
}
void WriteOrThrow(int fd, const void *data_void, std::size_t size) {
const uint8_t *data = static_cast<const uint8_t*>(data_void);
while (size) {
#if defined(_WIN32) || defined(_WIN64)
int ret;
#else
ssize_t ret;
#endif
errno = 0;
do {
ret =
#if defined(_WIN32) || defined(_WIN64)
_write
#else
write
#endif
(fd, data, GuardLarge(size));
} while (ret == -1 && errno == EINTR);
UTIL_THROW_IF_ARG(ret < 1, FDException, (fd), "while writing " << size << " bytes");
data += ret;
size -= ret;
}
}
void WriteOrThrow(FILE *to, const void *data, std::size_t size) {
if (!size) return;
UTIL_THROW_IF(1 != std::fwrite(data, size, 1, to), ErrnoException, "Short write; requested size " << size);
}
#if defined(_WIN32) || defined(_WIN64)
namespace {
const std::size_t kMaxDWORD = static_cast<std::size_t>(4294967295UL);
} // namespace
#endif
void ErsatzPRead(int fd, void *to_void, std::size_t size, uint64_t off) {
uint8_t *to = static_cast<uint8_t*>(to_void);
while (size) {
#if defined(_WIN32) || defined(_WIN64)
/* BROKEN: changes file pointer. Even if you save it and change it back, it won't be safe to use concurrently with write() or read() which lmplz does. */
// size_t might be 64-bit. DWORD is always 32.
DWORD reading = static_cast<DWORD>(std::min<std::size_t>(kMaxDWORD, size));
DWORD ret;
OVERLAPPED overlapped;
memset(&overlapped, 0, sizeof(OVERLAPPED));
overlapped.Offset = static_cast<DWORD>(off);
overlapped.OffsetHigh = static_cast<DWORD>(off >> 32);
UTIL_THROW_IF(!ReadFile((HANDLE)_get_osfhandle(fd), to, reading, &ret, &overlapped), Exception, "ReadFile failed for offset " << off);
#else
ssize_t ret;
errno = 0;
ret =
#ifdef OS_ANDROID
pread64
#else
pread
#endif
(fd, to, GuardLarge(size), off);
if (ret <= 0) {
if (ret == -1 && errno == EINTR) continue;
UTIL_THROW_IF(ret == 0, EndOfFileException, " for reading " << size << " bytes at " << off << " from " << NameFromFD(fd));
UTIL_THROW_ARG(FDException, (fd), "while reading " << size << " bytes at offset " << off);
}
#endif
size -= ret;
off += ret;
to += ret;
}
}
void ErsatzPWrite(int fd, const void *from_void, std::size_t size, uint64_t off) {
const uint8_t *from = static_cast<const uint8_t*>(from_void);
while(size) {
#if defined(_WIN32) || defined(_WIN64)
/* Changes file pointer. Even if you save it and change it back, it won't be safe to use concurrently with write() or read() */
// size_t might be 64-bit. DWORD is always 32.
DWORD writing = static_cast<DWORD>(std::min<std::size_t>(kMaxDWORD, size));
DWORD ret;
OVERLAPPED overlapped;
memset(&overlapped, 0, sizeof(OVERLAPPED));
overlapped.Offset = static_cast<DWORD>(off);
overlapped.OffsetHigh = static_cast<DWORD>(off >> 32);
UTIL_THROW_IF(!WriteFile((HANDLE)_get_osfhandle(fd), from, writing, &ret, &overlapped), Exception, "WriteFile failed for offset " << off);
#else
ssize_t ret;
errno = 0;
ret =
#ifdef OS_ANDROID
pwrite64
#else
pwrite
#endif
(fd, from, GuardLarge(size), off);
if (ret <= 0) {
if (ret == -1 && errno == EINTR) continue;
UTIL_THROW_IF(ret == 0, EndOfFileException, " for writing " << size << " bytes at " << off << " from " << NameFromFD(fd));
UTIL_THROW_ARG(FDException, (fd), "while writing " << size << " bytes at offset " << off);
}
#endif
size -= ret;
off += ret;
from += ret;
}
}
void FSyncOrThrow(int fd) {
// Apparently windows doesn't have fsync?
#if !defined(_WIN32) && !defined(_WIN64)
UTIL_THROW_IF_ARG(-1 == fsync(fd), FDException, (fd), "while syncing");
#endif
}
namespace {
// Static assert for 64-bit off_t size.
#if !defined(_WIN32) && !defined(_WIN64) && !defined(OS_ANDROID)
template <unsigned> struct CheckOffT;
template <> struct CheckOffT<8> {
struct True {};
};
// If there's a compiler error on the next line, then off_t isn't 64 bit. And
// that makes me a sad panda.
typedef CheckOffT<sizeof(off_t)>::True IgnoredType;
#endif
// Can't we all just get along?
void InternalSeek(int fd, int64_t off, int whence) {
if (
#if defined __MINGW32__
// Does this handle 64-bit?
(off_t)-1 == lseek(fd, off, whence)
#elif defined(_WIN32) || defined(_WIN64)
(__int64)-1 == _lseeki64(fd, off, whence)
#elif defined(OS_ANDROID)
(off64_t)-1 == lseek64(fd, off, whence)
#else
(off_t)-1 == lseek(fd, off, whence)
#endif
) UTIL_THROW_ARG(FDException, (fd), "while seeking to " << off << " whence " << whence);
}
} // namespace
void SeekOrThrow(int fd, uint64_t off) {
InternalSeek(fd, off, SEEK_SET);
}
void AdvanceOrThrow(int fd, int64_t off) {
InternalSeek(fd, off, SEEK_CUR);
}
void SeekEnd(int fd) {
InternalSeek(fd, 0, SEEK_END);
}
std::FILE *FDOpenOrThrow(scoped_fd &file) {
std::FILE *ret = fdopen(file.get(), "r+b");
UTIL_THROW_IF_ARG(!ret, FDException, (file.get()), "Could not fdopen for write");
file.release();
return ret;
}
std::FILE *FDOpenReadOrThrow(scoped_fd &file) {
std::FILE *ret = fdopen(file.get(), "rb");
UTIL_THROW_IF_ARG(!ret, FDException, (file.get()), "Could not fdopen for read");
file.release();
return ret;
}
// Sigh. Windows temporary file creation is full of race conditions.
#if defined(_WIN32) || defined(_WIN64)
/* mkstemp extracted from libc/sysdeps/posix/tempname.c. Copyright
(C) 1991-1999, 2000, 2001, 2006 Free Software Foundation, Inc.
The GNU C Library is free software; you can redistribute it and/or
modify it under the terms of the GNU Lesser General Public
License as published by the Free Software Foundation; either
version 2.1 of the License, or (at your option) any later version. */
/* This has been modified from the original version to rename the function and
* set the Windows temporary flag. */
static const char letters[] =
"abcdefghijklmnopqrstuvwxyzABCDEFGHIJKLMNOPQRSTUVWXYZ0123456789";
/* Generate a temporary file name based on TMPL. TMPL must match the
rules for mk[s]temp (i.e. end in "XXXXXX"). The name constructed
does not exist at the time of the call to mkstemp. TMPL is
overwritten with the result. */
int
mkstemp_and_unlink(char *tmpl)
{
int len;
char *XXXXXX;
static unsigned long long value;
unsigned long long random_time_bits;
unsigned int count;
int fd = -1;
int save_errno = errno;
/* A lower bound on the number of temporary files to attempt to
generate. The maximum total number of temporary file names that
can exist for a given template is 62**6. It should never be
necessary to try all these combinations. Instead if a reasonable
number of names is tried (we define reasonable as 62**3) fail to
give the system administrator the chance to remove the problems. */
#define ATTEMPTS_MIN (62 * 62 * 62)
/* The number of times to attempt to generate a temporary file. To
conform to POSIX, this must be no smaller than TMP_MAX. */
#if ATTEMPTS_MIN < TMP_MAX
unsigned int attempts = TMP_MAX;
#else
unsigned int attempts = ATTEMPTS_MIN;
#endif
len = strlen (tmpl);
if (len < 6 || strcmp (&tmpl[len - 6], "XXXXXX"))
{
errno = EINVAL;
return -1;
}
/* This is where the Xs start. */
XXXXXX = &tmpl[len - 6];
/* Get some more or less random data. */
{
SYSTEMTIME stNow;
FILETIME ftNow;
// get system time
GetSystemTime(&stNow);
stNow.wMilliseconds = 500;
if (!SystemTimeToFileTime(&stNow, &ftNow))
{
errno = -1;
return -1;
}
random_time_bits = (((unsigned long long)ftNow.dwHighDateTime << 32)
| (unsigned long long)ftNow.dwLowDateTime);
}
value += random_time_bits ^ (unsigned long long)GetCurrentThreadId ();
for (count = 0; count < attempts; value += 7777, ++count)
{
unsigned long long v = value;
/* Fill in the random bits. */
XXXXXX[0] = letters[v % 62];
v /= 62;
XXXXXX[1] = letters[v % 62];
v /= 62;
XXXXXX[2] = letters[v % 62];
v /= 62;
XXXXXX[3] = letters[v % 62];
v /= 62;
XXXXXX[4] = letters[v % 62];
v /= 62;
XXXXXX[5] = letters[v % 62];
/* Modified for windows and to unlink */
// fd = open (tmpl, O_RDWR | O_CREAT | O_EXCL, _S_IREAD | _S_IWRITE);
int flags = _O_RDWR | _O_CREAT | _O_EXCL | _O_BINARY;
flags |= _O_TEMPORARY;
fd = _open (tmpl, flags, _S_IREAD | _S_IWRITE);
if (fd >= 0)
{
errno = save_errno;
return fd;
}
else if (errno != EEXIST)
return -1;
}
/* We got out of the loop because we ran out of combinations to try. */
errno = EEXIST;
return -1;
}
#else
int
mkstemp_and_unlink(char *tmpl) {
int ret = mkstemp(tmpl);
if (ret != -1) {
UTIL_THROW_IF(unlink(tmpl), ErrnoException, "while deleting delete " << tmpl);
}
return ret;
}
#endif
// If it's a directory, add a /. This lets users say -T /tmp without creating
// /tmpAAAAAA
void NormalizeTempPrefix(std::string &base) {
if (base.empty()) return;
if (base[base.size() - 1] == '/') return;
struct stat sb;
// It's fine for it to not exist.
if (-1 == stat(base.c_str(), &sb)) return;
if (
#if defined(_WIN32) || defined(_WIN64)
sb.st_mode & _S_IFDIR
#else
S_ISDIR(sb.st_mode)
#endif
) base += '/';
}
int MakeTemp(const StringPiece &base) {
std::string name(base.data(), base.size());
name += "XXXXXX";
name.push_back(0);
int ret;
UTIL_THROW_IF(-1 == (ret = mkstemp_and_unlink(&name[0])), ErrnoException, "while making a temporary based on " << base);
return ret;
}
std::FILE *FMakeTemp(const StringPiece &base) {
util::scoped_fd file(MakeTemp(base));
return FDOpenOrThrow(file);
}
int DupOrThrow(int fd) {
int ret = dup(fd);
UTIL_THROW_IF_ARG(ret == -1, FDException, (fd), "in duplicating the file descriptor");
return ret;
}
namespace {
// Try to name things but be willing to fail too.
bool TryName(int fd, std::string &out) {
#if defined(_WIN32) || defined(_WIN64)
return false;
#else
std::string name("/proc/self/fd/");
std::ostringstream convert;
convert << fd;
name += convert.str();
struct stat sb;
if (-1 == lstat(name.c_str(), &sb))
return false;
out.resize(sb.st_size + 1);
// lstat gave us a size, but I've seen it grow, possibly due to symlinks on top of symlinks.
while (true) {
ssize_t ret = readlink(name.c_str(), &out[0], out.size());
if (-1 == ret)
return false;
if ((size_t)ret < out.size()) {
out.resize(ret);
break;
}
// Exponential growth.
out.resize(out.size() * 2);
}
// Don't use the non-file names.
if (!out.empty() && out[0] != '/')
return false;
return true;
#endif
}
} // namespace
std::string NameFromFD(int fd) {
std::string ret;
if (TryName(fd, ret)) return ret;
switch (fd) {
case 0: return "stdin";
case 1: return "stdout";
case 2: return "stderr";
}
ret = "fd ";
std::ostringstream convert;
convert << fd;
ret += convert.str();
return ret;
}
} // namespace util
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