blob: ff801adf8fe7efe5e4443ea0868e38bb69d8bea1 [file] [log] [blame]
// Copyright (c) 2012, the Dart project authors. Please see the AUTHORS file
// for details. All rights reserved. Use of this source code is governed by a
// BSD-style license that can be found in the LICENSE file.
#include "platform/globals.h"
#if defined(TARGET_OS_LINUX)
#include "bin/file.h"
#include <errno.h> // NOLINT
#include <fcntl.h> // NOLINT
#include <sys/stat.h> // NOLINT
#include <sys/types.h> // NOLINT
#include <sys/sendfile.h> // NOLINT
#include <unistd.h> // NOLINT
#include <libgen.h> // NOLINT
#include "platform/signal_blocker.h"
#include "bin/builtin.h"
#include "bin/log.h"
namespace dart {
namespace bin {
class FileHandle {
public:
explicit FileHandle(int fd) : fd_(fd) { }
~FileHandle() { }
int fd() const { return fd_; }
void set_fd(int fd) { fd_ = fd; }
private:
int fd_;
DISALLOW_COPY_AND_ASSIGN(FileHandle);
};
File::~File() {
Close();
delete handle_;
}
void File::Close() {
ASSERT(handle_->fd() >= 0);
if (handle_->fd() == STDOUT_FILENO) {
// If stdout, redirect fd to /dev/null.
int null_fd = TEMP_FAILURE_RETRY(open("/dev/null", O_WRONLY));
ASSERT(null_fd >= 0);
VOID_TEMP_FAILURE_RETRY(dup2(null_fd, handle_->fd()));
VOID_TEMP_FAILURE_RETRY(close(null_fd));
} else {
int err = TEMP_FAILURE_RETRY(close(handle_->fd()));
if (err != 0) {
const int kBufferSize = 1024;
char error_buf[kBufferSize];
Log::PrintErr("%s\n", strerror_r(errno, error_buf, kBufferSize));
}
}
handle_->set_fd(kClosedFd);
}
intptr_t File::GetFD() {
return handle_->fd();
}
bool File::IsClosed() {
return handle_->fd() == kClosedFd;
}
int64_t File::Read(void* buffer, int64_t num_bytes) {
ASSERT(handle_->fd() >= 0);
return TEMP_FAILURE_RETRY(read(handle_->fd(), buffer, num_bytes));
}
int64_t File::Write(const void* buffer, int64_t num_bytes) {
ASSERT(handle_->fd() >= 0);
return TEMP_FAILURE_RETRY(write(handle_->fd(), buffer, num_bytes));
}
int64_t File::Position() {
ASSERT(handle_->fd() >= 0);
return NO_RETRY_EXPECTED(lseek64(handle_->fd(), 0, SEEK_CUR));
}
bool File::SetPosition(int64_t position) {
ASSERT(handle_->fd() >= 0);
return NO_RETRY_EXPECTED(lseek64(handle_->fd(), position, SEEK_SET)) >= 0;
}
bool File::Truncate(int64_t length) {
ASSERT(handle_->fd() >= 0);
return TEMP_FAILURE_RETRY(ftruncate64(handle_->fd(), length) != -1);
}
bool File::Flush() {
ASSERT(handle_->fd() >= 0);
return NO_RETRY_EXPECTED(fsync(handle_->fd())) != -1;
}
bool File::Lock(File::LockType lock, int64_t start, int64_t end) {
ASSERT(handle_->fd() >= 0);
ASSERT(end == -1 || end > start);
struct flock fl;
switch (lock) {
case File::kLockUnlock:
fl.l_type = F_UNLCK;
break;
case File::kLockShared:
fl.l_type = F_RDLCK;
break;
case File::kLockExclusive:
fl.l_type = F_WRLCK;
break;
default:
return false;
}
fl.l_whence = SEEK_SET;
fl.l_start = start;
fl.l_len = end == -1 ? 0 : end - start;
// fcntl does not block, but fails if the lock cannot be acquired.
int rc = fcntl(handle_->fd(), F_SETLK, &fl);
return rc != -1;
}
int64_t File::Length() {
ASSERT(handle_->fd() >= 0);
struct stat64 st;
if (TEMP_FAILURE_RETRY(fstat64(handle_->fd(), &st)) == 0) {
return st.st_size;
}
return -1;
}
File* File::Open(const char* name, FileOpenMode mode) {
// Report errors for non-regular files.
struct stat64 st;
if (TEMP_FAILURE_RETRY(stat64(name, &st)) == 0) {
// Only accept regular files and character devices.
if (!S_ISREG(st.st_mode) && !S_ISCHR(st.st_mode)) {
errno = (S_ISDIR(st.st_mode)) ? EISDIR : ENOENT;
return NULL;
}
}
int flags = O_RDONLY;
if ((mode & kWrite) != 0) {
ASSERT((mode & kWriteOnly) == 0);
flags = (O_RDWR | O_CREAT);
}
if ((mode & kWriteOnly) != 0) {
ASSERT((mode & kWrite) == 0);
flags = (O_WRONLY | O_CREAT);
}
if ((mode & kTruncate) != 0) {
flags = flags | O_TRUNC;
}
flags |= O_CLOEXEC;
int fd = TEMP_FAILURE_RETRY(open64(name, flags, 0666));
if (fd < 0) {
return NULL;
}
if ((((mode & kWrite) != 0) && ((mode & kTruncate) == 0)) ||
(((mode & kWriteOnly) != 0) && ((mode & kTruncate) == 0))) {
int64_t position = NO_RETRY_EXPECTED(lseek64(fd, 0, SEEK_END));
if (position < 0) {
return NULL;
}
}
return new File(new FileHandle(fd));
}
File* File::OpenStdio(int fd) {
if (fd < 0 || 2 < fd) return NULL;
return new File(new FileHandle(fd));
}
bool File::Exists(const char* name) {
struct stat64 st;
if (TEMP_FAILURE_RETRY(stat64(name, &st)) == 0) {
return S_ISREG(st.st_mode);
} else {
return false;
}
}
bool File::Create(const char* name) {
int fd = TEMP_FAILURE_RETRY(
open64(name, O_RDONLY | O_CREAT | O_CLOEXEC, 0666));
if (fd < 0) {
return false;
}
return (TEMP_FAILURE_RETRY(close(fd)) == 0);
}
bool File::CreateLink(const char* name, const char* target) {
return NO_RETRY_EXPECTED(symlink(target, name)) == 0;
}
bool File::Delete(const char* name) {
File::Type type = File::GetType(name, true);
if (type == kIsFile) {
return NO_RETRY_EXPECTED(unlink(name)) == 0;
} else if (type == kIsDirectory) {
errno = EISDIR;
} else {
errno = ENOENT;
}
return false;
}
bool File::DeleteLink(const char* name) {
File::Type type = File::GetType(name, false);
if (type == kIsLink) {
return NO_RETRY_EXPECTED(unlink(name)) == 0;
}
errno = EINVAL;
return false;
}
bool File::Rename(const char* old_path, const char* new_path) {
File::Type type = File::GetType(old_path, true);
if (type == kIsFile) {
return NO_RETRY_EXPECTED(rename(old_path, new_path)) == 0;
} else if (type == kIsDirectory) {
errno = EISDIR;
} else {
errno = ENOENT;
}
return false;
}
bool File::RenameLink(const char* old_path, const char* new_path) {
File::Type type = File::GetType(old_path, false);
if (type == kIsLink) {
return NO_RETRY_EXPECTED(rename(old_path, new_path)) == 0;
} else if (type == kIsDirectory) {
errno = EISDIR;
} else {
errno = EINVAL;
}
return false;
}
bool File::Copy(const char* old_path, const char* new_path) {
File::Type type = File::GetType(old_path, true);
if (type == kIsFile) {
struct stat64 st;
if (TEMP_FAILURE_RETRY(stat64(old_path, &st)) != 0) {
return false;
}
int old_fd = TEMP_FAILURE_RETRY(open64(old_path, O_RDONLY | O_CLOEXEC));
if (old_fd < 0) {
return false;
}
int new_fd = TEMP_FAILURE_RETRY(
open64(new_path, O_WRONLY | O_TRUNC | O_CREAT | O_CLOEXEC, st.st_mode));
if (new_fd < 0) {
VOID_TEMP_FAILURE_RETRY(close(old_fd));
return false;
}
int64_t offset = 0;
intptr_t result = 1;
while (result > 0) {
// Loop to ensure we copy everything, and not only up to 2GB.
result = NO_RETRY_EXPECTED(
sendfile64(new_fd, old_fd, &offset, kMaxUint32));
}
// From sendfile man pages:
// Applications may wish to fall back to read(2)/write(2) in the case
// where sendfile() fails with EINVAL or ENOSYS.
if (result < 0 && (errno == EINVAL || errno == ENOSYS)) {
const intptr_t kBufferSize = 8 * KB;
uint8_t buffer[kBufferSize];
while ((result = TEMP_FAILURE_RETRY(
read(old_fd, buffer, kBufferSize))) > 0) {
int wrote = TEMP_FAILURE_RETRY(write(new_fd, buffer, result));
if (wrote != result) {
result = -1;
break;
}
}
}
int e = errno;
VOID_TEMP_FAILURE_RETRY(close(old_fd));
VOID_TEMP_FAILURE_RETRY(close(new_fd));
if (result < 0) {
VOID_NO_RETRY_EXPECTED(unlink(new_path));
errno = e;
return false;
}
return true;
} else if (type == kIsDirectory) {
errno = EISDIR;
} else {
errno = ENOENT;
}
return false;
}
int64_t File::LengthFromPath(const char* name) {
struct stat64 st;
if (TEMP_FAILURE_RETRY(stat64(name, &st)) == 0) {
return st.st_size;
}
return -1;
}
static int64_t TimespecToMilliseconds(const struct timespec& t) {
return static_cast<int64_t>(t.tv_sec) * 1000L +
static_cast<int64_t>(t.tv_nsec) / 1000000L;
}
void File::Stat(const char* name, int64_t* data) {
struct stat64 st;
if (TEMP_FAILURE_RETRY(stat64(name, &st)) == 0) {
if (S_ISREG(st.st_mode)) {
data[kType] = kIsFile;
} else if (S_ISDIR(st.st_mode)) {
data[kType] = kIsDirectory;
} else if (S_ISLNK(st.st_mode)) {
data[kType] = kIsLink;
} else {
data[kType] = kDoesNotExist;
}
data[kCreatedTime] = TimespecToMilliseconds(st.st_ctim);
data[kModifiedTime] = TimespecToMilliseconds(st.st_mtim);
data[kAccessedTime] = TimespecToMilliseconds(st.st_atim);
data[kMode] = st.st_mode;
data[kSize] = st.st_size;
} else {
data[kType] = kDoesNotExist;
}
}
time_t File::LastModified(const char* name) {
struct stat64 st;
if (TEMP_FAILURE_RETRY(stat64(name, &st)) == 0) {
return st.st_mtime;
}
return -1;
}
char* File::LinkTarget(const char* pathname) {
struct stat64 link_stats;
if (TEMP_FAILURE_RETRY(lstat64(pathname, &link_stats)) != 0) return NULL;
if (!S_ISLNK(link_stats.st_mode)) {
errno = ENOENT;
return NULL;
}
// Don't rely on the link_stats.st_size for the size of the link
// target. For some filesystems, e.g. procfs, this value is always
// 0. Also the link might have changed before the readlink call.
const int kBufferSize = PATH_MAX + 1;
char target[kBufferSize];
size_t target_size = TEMP_FAILURE_RETRY(
readlink(pathname, target, kBufferSize));
if (target_size <= 0) {
return NULL;
}
char* target_name = reinterpret_cast<char*>(malloc(target_size + 1));
if (target_name == NULL) {
return NULL;
}
memmove(target_name, target, target_size);
target_name[target_size] = '\0';
return target_name;
}
bool File::IsAbsolutePath(const char* pathname) {
return (pathname != NULL && pathname[0] == '/');
}
char* File::GetCanonicalPath(const char* pathname) {
char* abs_path = NULL;
if (pathname != NULL) {
do {
abs_path = realpath(pathname, NULL);
} while (abs_path == NULL && errno == EINTR);
ASSERT(abs_path == NULL || IsAbsolutePath(abs_path));
}
return abs_path;
}
const char* File::PathSeparator() {
return "/";
}
const char* File::StringEscapedPathSeparator() {
return "/";
}
File::StdioHandleType File::GetStdioHandleType(int fd) {
ASSERT(0 <= fd && fd <= 2);
struct stat64 buf;
int result = TEMP_FAILURE_RETRY(fstat64(fd, &buf));
if (result == -1) {
const int kBufferSize = 1024;
char error_buf[kBufferSize];
FATAL2("Failed stat on file descriptor %d: %s", fd,
strerror_r(errno, error_buf, kBufferSize));
}
if (S_ISCHR(buf.st_mode)) return kTerminal;
if (S_ISFIFO(buf.st_mode)) return kPipe;
if (S_ISSOCK(buf.st_mode)) return kSocket;
if (S_ISREG(buf.st_mode)) return kFile;
return kOther;
}
File::Type File::GetType(const char* pathname, bool follow_links) {
struct stat64 entry_info;
int stat_success;
if (follow_links) {
stat_success = TEMP_FAILURE_RETRY(stat64(pathname, &entry_info));
} else {
stat_success = TEMP_FAILURE_RETRY(lstat64(pathname, &entry_info));
}
if (stat_success == -1) return File::kDoesNotExist;
if (S_ISDIR(entry_info.st_mode)) return File::kIsDirectory;
if (S_ISREG(entry_info.st_mode)) return File::kIsFile;
if (S_ISLNK(entry_info.st_mode)) return File::kIsLink;
return File::kDoesNotExist;
}
File::Identical File::AreIdentical(const char* file_1, const char* file_2) {
struct stat64 file_1_info;
struct stat64 file_2_info;
if (TEMP_FAILURE_RETRY(lstat64(file_1, &file_1_info)) == -1 ||
TEMP_FAILURE_RETRY(lstat64(file_2, &file_2_info)) == -1) {
return File::kError;
}
return (file_1_info.st_ino == file_2_info.st_ino &&
file_1_info.st_dev == file_2_info.st_dev) ?
File::kIdentical :
File::kDifferent;
}
} // namespace bin
} // namespace dart
#endif // defined(TARGET_OS_LINUX)