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#include "util/file.hh"
#include "util/exception.hh"
#include <cstdlib>
#include <cstdio>
#include <iostream>
#include <assert.h>
#include <sys/types.h>
#include <sys/stat.h>
#include <fcntl.h>
#include <stdint.h>
#if 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();
}
}
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, _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(_WIN32) || defined(_WIN64)
__int64 ret = _filelengthi64(fd);
return (ret == -1) ? kBadSize : ret;
#else
struct stat sb;
if (fstat(fd, &sb) == -1 || (!sb.st_size && !S_ISREG(sb.st_mode))) return kBadSize;
return sb.st_size;
#endif
}
void ResizeOrThrow(int fd, uint64_t to) {
#if defined(_WIN32) || defined(_WIN64)
UTIL_THROW_IF(_chsize_s(fd, to), ErrnoException, "Resizing to " << to << " bytes failed");
#else
UTIL_THROW_IF(ftruncate(fd, to), ErrnoException, "Resizing to " << to << " bytes failed");
#endif
}
#ifdef WIN32
typedef int ssize_t;
#endif
void ReadOrThrow(int fd, void *to_void, std::size_t amount) {
uint8_t *to = static_cast<uint8_t*>(to_void);
while (amount) {
ssize_t ret = read(fd, to, amount);
UTIL_THROW_IF(ret == -1, ErrnoException, "Reading " << amount << " from fd " << fd << " failed.");
UTIL_THROW_IF(ret == 0, EndOfFileException, "Hit EOF in fd " << 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) {
ssize_t ret = read(fd, to, remaining);
UTIL_THROW_IF(ret == -1, ErrnoException, "Reading " << remaining << " from fd " << fd << " failed.");
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) {
ssize_t ret = write(fd, data, size);
if (ret < 1) UTIL_THROW(util::ErrnoException, "Write failed");
data += ret;
size -= ret;
}
}
void WriteOrThrow(FILE *to, const void *data, std::size_t size) {
assert(size);
if (1 != std::fwrite(data, size, 1, to)) UTIL_THROW(util::ErrnoException, "Short write; requested size " << size);
}
void FSyncOrThrow(int fd) {
// Apparently windows doesn't have fsync?
#if !defined(_WIN32) && !defined(_WIN64)
UTIL_THROW_IF(-1 == fsync(fd), ErrnoException, "Sync of " << fd << " failed.");
#endif
}
namespace {
void InternalSeek(int fd, int64_t off, int whence) {
#if defined(_WIN32) || defined(_WIN64)
UTIL_THROW_IF((__int64)-1 == _lseeki64(fd, off, whence), ErrnoException, "Windows seek failed");
#else
UTIL_THROW_IF((off_t)-1 == lseek(fd, off, whence), ErrnoException, "Seek failed");
#endif
}
} // 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");
if (!ret) UTIL_THROW(util::ErrnoException, "Could not fdopen");
file.release();
return ret;
}
std::FILE *FOpenOrThrow(const char *path, const char *mode) {
std::FILE *ret;
UTIL_THROW_IF(!(ret = fopen(path, mode)), util::ErrnoException, "Could not fopen " << path << " for " << mode);
return ret;
}
TempMaker::TempMaker(const std::string &prefix) : base_(prefix) {
base_ += "XXXXXX";
}
// 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, bool and_unlink)
{
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;
if (and_unlink) 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, bool and_unlink) {
int ret = mkstemp(tmpl);
if (ret != -1 && and_unlink) {
UTIL_THROW_IF(unlink(tmpl), util::ErrnoException, "Failed to delete " << tmpl);
}
return ret;
}
#endif
int TempMaker::Make() const {
std::string name(base_);
name.push_back(0);
int ret;
UTIL_THROW_IF(-1 == (ret = mkstemp_and_unlink(&name[0], true)), util::ErrnoException, "Failed to make a temporary based on " << base_);
return ret;
}
std::FILE *TempMaker::MakeFile() const {
util::scoped_fd file(Make());
return FDOpenOrThrow(file);
}
std::string TempMaker::Name(scoped_fd &opened) const {
std::string name(base_);
name.push_back(0);
int fd;
UTIL_THROW_IF(-1 == (fd = mkstemp_and_unlink(&name[0], false)), util::ErrnoException, "Failed to make a temporary based on " << base_);
opened.reset(fd);
return name;
}
} // namespace util
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