kicad/thirdparty/sentry-native/external/crashpad/util/file/file_io_posix.cc

283 lines
8.5 KiB
C++

// Copyright 2014 The Crashpad Authors
//
// Licensed under the Apache License, Version 2.0 (the "License");
// you may not use this file except in compliance with the License.
// You may obtain a copy of the License at
//
// http://www.apache.org/licenses/LICENSE-2.0
//
// Unless required by applicable law or agreed to in writing, software
// distributed under the License is distributed on an "AS IS" BASIS,
// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
// See the License for the specific language governing permissions and
// limitations under the License.
#include "util/file/file_io.h"
#include <errno.h>
#include <fcntl.h>
#include <sys/file.h>
#include <sys/mman.h>
#include <sys/stat.h>
#include <unistd.h>
#include <algorithm>
#include <limits>
#include "base/files/file_path.h"
#include "base/logging.h"
#include "base/notreached.h"
#include "base/posix/eintr_wrapper.h"
#include "base/strings/stringprintf.h"
#include "build/build_config.h"
#include "util/misc/random_string.h"
namespace crashpad {
namespace {
struct ReadTraits {
using BufferType = void*;
static FileOperationResult Operate(int fd, BufferType buffer, size_t size) {
return read(fd, buffer, size);
}
};
struct WriteTraits {
using BufferType = const void*;
static FileOperationResult Operate(int fd, BufferType buffer, size_t size) {
return write(fd, buffer, size);
}
};
template <typename Traits>
FileOperationResult ReadOrWrite(int fd,
typename Traits::BufferType buffer,
size_t size) {
constexpr size_t kMaxReadWriteSize =
static_cast<size_t>(std::numeric_limits<ssize_t>::max());
const size_t requested_bytes = std::min(size, kMaxReadWriteSize);
FileOperationResult transacted_bytes =
HANDLE_EINTR(Traits::Operate(fd, buffer, requested_bytes));
if (transacted_bytes < 0) {
return -1;
}
DCHECK_LE(static_cast<size_t>(transacted_bytes), requested_bytes);
return transacted_bytes;
}
FileHandle OpenFileForOutput(int rdwr_or_wronly,
const base::FilePath& path,
FileWriteMode mode,
FilePermissions permissions) {
#if BUILDFLAG(IS_FUCHSIA)
// O_NOCTTY is invalid on Fuchsia, and O_CLOEXEC isn't necessary.
int flags = 0;
#else
int flags = O_NOCTTY | O_CLOEXEC;
#endif
DCHECK(rdwr_or_wronly & (O_RDWR | O_WRONLY));
DCHECK_EQ(rdwr_or_wronly & ~(O_RDWR | O_WRONLY), 0);
flags |= rdwr_or_wronly;
switch (mode) {
case FileWriteMode::kReuseOrFail:
break;
case FileWriteMode::kReuseOrCreate:
flags |= O_CREAT;
break;
case FileWriteMode::kTruncateOrCreate:
flags |= O_CREAT | O_TRUNC;
break;
case FileWriteMode::kCreateOrFail:
flags |= O_CREAT | O_EXCL;
break;
}
return HANDLE_EINTR(
open(path.value().c_str(),
flags,
permissions == FilePermissions::kWorldReadable ? 0644 : 0600));
}
} // namespace
namespace internal {
FileOperationResult NativeWriteFile(FileHandle file,
const void* buffer,
size_t size) {
return ReadOrWrite<WriteTraits>(file, buffer, size);
}
} // namespace internal
FileOperationResult ReadFile(FileHandle file, void* buffer, size_t size) {
return ReadOrWrite<ReadTraits>(file, buffer, size);
}
FileHandle OpenFileForRead(const base::FilePath& path) {
int flags = O_RDONLY;
#if !BUILDFLAG(IS_FUCHSIA)
// O_NOCTTY is invalid on Fuchsia, and O_CLOEXEC isn't necessary.
flags |= O_NOCTTY | O_CLOEXEC;
#endif
return HANDLE_EINTR(open(path.value().c_str(), flags));
}
FileHandle OpenFileForWrite(const base::FilePath& path,
FileWriteMode mode,
FilePermissions permissions) {
return OpenFileForOutput(O_WRONLY, path, mode, permissions);
}
FileHandle OpenFileForReadAndWrite(const base::FilePath& path,
FileWriteMode mode,
FilePermissions permissions) {
return OpenFileForOutput(O_RDWR, path, mode, permissions);
}
FileHandle LoggingOpenFileForRead(const base::FilePath& path) {
FileHandle fd = OpenFileForRead(path);
PLOG_IF(ERROR, fd < 0) << "open " << path.value();
return fd;
}
FileHandle LoggingOpenFileForWrite(const base::FilePath& path,
FileWriteMode mode,
FilePermissions permissions) {
FileHandle fd = OpenFileForWrite(path, mode, permissions);
PLOG_IF(ERROR, fd < 0) << "open " << path.value();
return fd;
}
#if BUILDFLAG(IS_LINUX) || BUILDFLAG(IS_CHROMEOS)
FileHandle LoggingOpenMemoryFileForReadAndWrite(const base::FilePath& name) {
DCHECK(name.value().find('/') == std::string::npos);
int result = HANDLE_EINTR(memfd_create(name.value().c_str(), 0));
if (result >= 0 || errno != ENOSYS) {
PLOG_IF(ERROR, result < 0) << "memfd_create";
return result;
}
const char* tmp = getenv("TMPDIR");
tmp = tmp ? tmp : "/tmp";
result = HANDLE_EINTR(open(tmp, O_RDWR | O_EXCL | O_TMPFILE, 0600));
if (result >= 0 ||
// These are the expected possible error codes indicating that O_TMPFILE
// doesn't have kernel or filesystem support. O_TMPFILE was added in Linux
// 3.11. Experimentation confirms that at least Linux 2.6.29 and Linux
// 3.10 set errno to EISDIR. EOPNOTSUPP is returned when the filesystem
// doesn't support O_TMPFILE. The man pages also mention ENOENT as an
// error code to check, but the language implies it would only occur when
// |tmp| is also an invalid directory. EINVAL is mentioned as a possible
// error code for any invalid values in flags, but O_TMPFILE isn't
// mentioned explicitly in this context and hasn't been observed in
// practice.
(errno != EISDIR && errno != EOPNOTSUPP)) {
PLOG_IF(ERROR, result < 0) << "open";
return result;
}
std::string path = base::StringPrintf("%s/%s.%d.%s",
tmp,
name.value().c_str(),
getpid(),
RandomString().c_str());
result = HANDLE_EINTR(open(path.c_str(), O_RDWR | O_CREAT | O_EXCL, 0600));
if (result < 0) {
PLOG(ERROR) << "open";
return result;
}
if (unlink(path.c_str()) != 0) {
PLOG(WARNING) << "unlink";
}
return result;
}
#endif
FileHandle LoggingOpenFileForReadAndWrite(const base::FilePath& path,
FileWriteMode mode,
FilePermissions permissions) {
FileHandle fd = OpenFileForReadAndWrite(path, mode, permissions);
PLOG_IF(ERROR, fd < 0) << "open " << path.value();
return fd;
}
#if CRASHPAD_FLOCK_ALWAYS_SUPPORTED
FileLockingResult LoggingLockFile(FileHandle file,
FileLocking locking,
FileLockingBlocking blocking) {
int operation = (locking == FileLocking::kShared) ? LOCK_SH : LOCK_EX;
if (blocking == FileLockingBlocking::kNonBlocking)
operation |= LOCK_NB;
int rv = HANDLE_EINTR(flock(file, operation));
if (rv != 0) {
if (errno == EWOULDBLOCK) {
return FileLockingResult::kWouldBlock;
}
PLOG(ERROR) << "flock";
return FileLockingResult::kFailure;
}
return FileLockingResult::kSuccess;
}
bool LoggingUnlockFile(FileHandle file) {
int rv = flock(file, LOCK_UN);
PLOG_IF(ERROR, rv != 0) << "flock";
return rv == 0;
}
#endif // CRASHPAD_FLOCK_ALWAYS_SUPPORTED
FileOffset LoggingSeekFile(FileHandle file, FileOffset offset, int whence) {
off_t rv = lseek(file, offset, whence);
PLOG_IF(ERROR, rv < 0) << "lseek";
return rv;
}
bool LoggingTruncateFile(FileHandle file) {
if (HANDLE_EINTR(ftruncate(file, 0)) != 0) {
PLOG(ERROR) << "ftruncate";
return false;
}
return true;
}
bool LoggingCloseFile(FileHandle file) {
int rv = IGNORE_EINTR(close(file));
PLOG_IF(ERROR, rv != 0) << "close";
return rv == 0;
}
FileOffset LoggingFileSizeByHandle(FileHandle file) {
struct stat st;
if (fstat(file, &st) != 0) {
PLOG(ERROR) << "fstat";
return -1;
}
return st.st_size;
}
FileHandle StdioFileHandle(StdioStream stdio_stream) {
switch (stdio_stream) {
case StdioStream::kStandardInput:
return STDIN_FILENO;
case StdioStream::kStandardOutput:
return STDOUT_FILENO;
case StdioStream::kStandardError:
return STDERR_FILENO;
}
NOTREACHED();
return kInvalidFileHandle;
}
} // namespace crashpad