blob: ff92b90a7c3c32fdbb8ad7b15adf59d3be3e44a1 [file] [log] [blame]
// Copyright (c) 2012 The Chromium Authors. All rights reserved.
// Use of this source code is governed by a BSD-style license that can be
// found in the LICENSE file.
#include "base/platform_file.h"
#include <fcntl.h>
#include <errno.h>
#include <sys/stat.h>
#include <unistd.h>
#include "base/files/file_path.h"
#include "base/logging.h"
#include "base/metrics/sparse_histogram.h"
#include "base/posix/eintr_wrapper.h"
#include "base/strings/utf_string_conversions.h"
#include "base/threading/thread_restrictions.h"
#if defined(OS_ANDROID)
#include "base/os_compat_android.h"
#endif
namespace base {
// Make sure our Whence mappings match the system headers.
COMPILE_ASSERT(PLATFORM_FILE_FROM_BEGIN == SEEK_SET &&
PLATFORM_FILE_FROM_CURRENT == SEEK_CUR &&
PLATFORM_FILE_FROM_END == SEEK_END, whence_matches_system);
namespace {
#if defined(OS_BSD) || defined(OS_MACOSX) || defined(OS_NACL)
typedef struct stat stat_wrapper_t;
static int CallFstat(int fd, stat_wrapper_t *sb) {
base::ThreadRestrictions::AssertIOAllowed();
return fstat(fd, sb);
}
#else
typedef struct stat64 stat_wrapper_t;
static int CallFstat(int fd, stat_wrapper_t *sb) {
base::ThreadRestrictions::AssertIOAllowed();
return fstat64(fd, sb);
}
#endif
// NaCl doesn't provide the following system calls, so either simulate them or
// wrap them in order to minimize the number of #ifdef's in this file.
#if !defined(OS_NACL)
static bool IsOpenAppend(PlatformFile file) {
return (fcntl(file, F_GETFL) & O_APPEND) != 0;
}
static int CallFtruncate(PlatformFile file, int64 length) {
return HANDLE_EINTR(ftruncate(file, length));
}
static int CallFsync(PlatformFile file) {
return HANDLE_EINTR(fsync(file));
}
static int CallFutimes(PlatformFile file, const struct timeval times[2]) {
#ifdef __USE_XOPEN2K8
// futimens should be available, but futimes might not be
// http://pubs.opengroup.org/onlinepubs/9699919799/
timespec ts_times[2];
ts_times[0].tv_sec = times[0].tv_sec;
ts_times[0].tv_nsec = times[0].tv_usec * 1000;
ts_times[1].tv_sec = times[1].tv_sec;
ts_times[1].tv_nsec = times[1].tv_usec * 1000;
return futimens(file, ts_times);
#else
return futimes(file, times);
#endif
}
static PlatformFileError CallFctnlFlock(PlatformFile file, bool do_lock) {
struct flock lock;
lock.l_type = F_WRLCK;
lock.l_whence = SEEK_SET;
lock.l_start = 0;
lock.l_len = 0; // Lock entire file.
if (HANDLE_EINTR(fcntl(file, do_lock ? F_SETLK : F_UNLCK, &lock)) == -1)
return ErrnoToPlatformFileError(errno);
return PLATFORM_FILE_OK;
}
#else // defined(OS_NACL)
static bool IsOpenAppend(PlatformFile file) {
// NaCl doesn't implement fcntl. Since NaCl's write conforms to the POSIX
// standard and always appends if the file is opened with O_APPEND, just
// return false here.
return false;
}
static int CallFtruncate(PlatformFile file, int64 length) {
NOTIMPLEMENTED(); // NaCl doesn't implement ftruncate.
return 0;
}
static int CallFsync(PlatformFile file) {
NOTIMPLEMENTED(); // NaCl doesn't implement fsync.
return 0;
}
static int CallFutimes(PlatformFile file, const struct timeval times[2]) {
NOTIMPLEMENTED(); // NaCl doesn't implement futimes.
return 0;
}
static PlatformFileError CallFctnlFlock(PlatformFile file, bool do_lock) {
NOTIMPLEMENTED(); // NaCl doesn't implement flock struct.
return PLATFORM_FILE_ERROR_INVALID_OPERATION;
}
#endif // defined(OS_NACL)
} // namespace
// NaCl doesn't implement system calls to open files directly.
#if !defined(OS_NACL)
FILE* FdopenPlatformFile(PlatformFile file, const char* mode) {
return fdopen(file, mode);
}
#endif // !defined(OS_NACL)
bool ClosePlatformFile(PlatformFile file) {
base::ThreadRestrictions::AssertIOAllowed();
return !IGNORE_EINTR(close(file));
}
int64 SeekPlatformFile(PlatformFile file,
PlatformFileWhence whence,
int64 offset) {
base::ThreadRestrictions::AssertIOAllowed();
if (file < 0 || offset < 0)
return -1;
return lseek(file, static_cast<off_t>(offset), static_cast<int>(whence));
}
int ReadPlatformFile(PlatformFile file, int64 offset, char* data, int size) {
base::ThreadRestrictions::AssertIOAllowed();
if (file < 0 || size < 0)
return -1;
int bytes_read = 0;
int rv;
do {
rv = HANDLE_EINTR(pread(file, data + bytes_read,
size - bytes_read, offset + bytes_read));
if (rv <= 0)
break;
bytes_read += rv;
} while (bytes_read < size);
return bytes_read ? bytes_read : rv;
}
int ReadPlatformFileAtCurrentPos(PlatformFile file, char* data, int size) {
base::ThreadRestrictions::AssertIOAllowed();
if (file < 0 || size < 0)
return -1;
int bytes_read = 0;
int rv;
do {
rv = HANDLE_EINTR(read(file, data + bytes_read, size - bytes_read));
if (rv <= 0)
break;
bytes_read += rv;
} while (bytes_read < size);
return bytes_read ? bytes_read : rv;
}
int ReadPlatformFileNoBestEffort(PlatformFile file, int64 offset,
char* data, int size) {
base::ThreadRestrictions::AssertIOAllowed();
if (file < 0)
return -1;
return HANDLE_EINTR(pread(file, data, size, offset));
}
int ReadPlatformFileCurPosNoBestEffort(PlatformFile file,
char* data, int size) {
base::ThreadRestrictions::AssertIOAllowed();
if (file < 0 || size < 0)
return -1;
return HANDLE_EINTR(read(file, data, size));
}
int WritePlatformFile(PlatformFile file, int64 offset,
const char* data, int size) {
base::ThreadRestrictions::AssertIOAllowed();
if (IsOpenAppend(file))
return WritePlatformFileAtCurrentPos(file, data, size);
if (file < 0 || size < 0)
return -1;
int bytes_written = 0;
int rv;
do {
rv = HANDLE_EINTR(pwrite(file, data + bytes_written,
size - bytes_written, offset + bytes_written));
if (rv <= 0)
break;
bytes_written += rv;
} while (bytes_written < size);
return bytes_written ? bytes_written : rv;
}
int WritePlatformFileAtCurrentPos(PlatformFile file,
const char* data, int size) {
base::ThreadRestrictions::AssertIOAllowed();
if (file < 0 || size < 0)
return -1;
int bytes_written = 0;
int rv;
do {
rv = HANDLE_EINTR(write(file, data + bytes_written, size - bytes_written));
if (rv <= 0)
break;
bytes_written += rv;
} while (bytes_written < size);
return bytes_written ? bytes_written : rv;
}
int WritePlatformFileCurPosNoBestEffort(PlatformFile file,
const char* data, int size) {
base::ThreadRestrictions::AssertIOAllowed();
if (file < 0 || size < 0)
return -1;
return HANDLE_EINTR(write(file, data, size));
}
bool TruncatePlatformFile(PlatformFile file, int64 length) {
base::ThreadRestrictions::AssertIOAllowed();
return ((file >= 0) && !CallFtruncate(file, length));
}
bool FlushPlatformFile(PlatformFile file) {
base::ThreadRestrictions::AssertIOAllowed();
return !CallFsync(file);
}
bool TouchPlatformFile(PlatformFile file, const base::Time& last_access_time,
const base::Time& last_modified_time) {
base::ThreadRestrictions::AssertIOAllowed();
if (file < 0)
return false;
timeval times[2];
times[0] = last_access_time.ToTimeVal();
times[1] = last_modified_time.ToTimeVal();
return !CallFutimes(file, times);
}
bool GetPlatformFileInfo(PlatformFile file, PlatformFileInfo* info) {
if (!info)
return false;
stat_wrapper_t file_info;
if (CallFstat(file, &file_info))
return false;
info->is_directory = S_ISDIR(file_info.st_mode);
info->is_symbolic_link = S_ISLNK(file_info.st_mode);
info->size = file_info.st_size;
#if defined(OS_LINUX)
const time_t last_modified_sec = file_info.st_mtim.tv_sec;
const int64 last_modified_nsec = file_info.st_mtim.tv_nsec;
const time_t last_accessed_sec = file_info.st_atim.tv_sec;
const int64 last_accessed_nsec = file_info.st_atim.tv_nsec;
const time_t creation_time_sec = file_info.st_ctim.tv_sec;
const int64 creation_time_nsec = file_info.st_ctim.tv_nsec;
#elif defined(OS_ANDROID)
const time_t last_modified_sec = file_info.st_mtime;
const int64 last_modified_nsec = file_info.st_mtime_nsec;
const time_t last_accessed_sec = file_info.st_atime;
const int64 last_accessed_nsec = file_info.st_atime_nsec;
const time_t creation_time_sec = file_info.st_ctime;
const int64 creation_time_nsec = file_info.st_ctime_nsec;
#elif defined(OS_MACOSX) || defined(OS_IOS) || defined(OS_BSD)
const time_t last_modified_sec = file_info.st_mtimespec.tv_sec;
const int64 last_modified_nsec = file_info.st_mtimespec.tv_nsec;
const time_t last_accessed_sec = file_info.st_atimespec.tv_sec;
const int64 last_accessed_nsec = file_info.st_atimespec.tv_nsec;
const time_t creation_time_sec = file_info.st_ctimespec.tv_sec;
const int64 creation_time_nsec = file_info.st_ctimespec.tv_nsec;
#else
// TODO(gavinp): Investigate a good high resolution option for OS_NACL.
const time_t last_modified_sec = file_info.st_mtime;
const int64 last_modified_nsec = 0;
const time_t last_accessed_sec = file_info.st_atime;
const int64 last_accessed_nsec = 0;
const time_t creation_time_sec = file_info.st_ctime;
const int64 creation_time_nsec = 0;
#endif
info->last_modified =
base::Time::FromTimeT(last_modified_sec) +
base::TimeDelta::FromMicroseconds(last_modified_nsec /
base::Time::kNanosecondsPerMicrosecond);
info->last_accessed =
base::Time::FromTimeT(last_accessed_sec) +
base::TimeDelta::FromMicroseconds(last_accessed_nsec /
base::Time::kNanosecondsPerMicrosecond);
info->creation_time =
base::Time::FromTimeT(creation_time_sec) +
base::TimeDelta::FromMicroseconds(creation_time_nsec /
base::Time::kNanosecondsPerMicrosecond);
return true;
}
PlatformFileError LockPlatformFile(PlatformFile file) {
return CallFctnlFlock(file, true);
}
PlatformFileError UnlockPlatformFile(PlatformFile file) {
return CallFctnlFlock(file, false);
}
PlatformFileError ErrnoToPlatformFileError(int saved_errno) {
switch (saved_errno) {
case EACCES:
case EISDIR:
case EROFS:
case EPERM:
return PLATFORM_FILE_ERROR_ACCESS_DENIED;
#if !defined(OS_NACL) // ETXTBSY not defined by NaCl.
case ETXTBSY:
return PLATFORM_FILE_ERROR_IN_USE;
#endif
case EEXIST:
return PLATFORM_FILE_ERROR_EXISTS;
case ENOENT:
return PLATFORM_FILE_ERROR_NOT_FOUND;
case EMFILE:
return PLATFORM_FILE_ERROR_TOO_MANY_OPENED;
case ENOMEM:
return PLATFORM_FILE_ERROR_NO_MEMORY;
case ENOSPC:
return PLATFORM_FILE_ERROR_NO_SPACE;
case ENOTDIR:
return PLATFORM_FILE_ERROR_NOT_A_DIRECTORY;
default:
#if !defined(OS_NACL) // NaCl build has no metrics code.
UMA_HISTOGRAM_SPARSE_SLOWLY("PlatformFile.UnknownErrors.Posix",
saved_errno);
#endif
return PLATFORM_FILE_ERROR_FAILED;
}
}
} // namespace base