Nagram/TMessagesProj/jni/voip/webrtc/base/files/dir_reader_linux.h
2020-09-30 16:48:47 +03:00

102 lines
2.1 KiB
C++

// 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.
#ifndef BASE_FILES_DIR_READER_LINUX_H_
#define BASE_FILES_DIR_READER_LINUX_H_
#include <errno.h>
#include <fcntl.h>
#include <stddef.h>
#include <stdint.h>
#include <sys/syscall.h>
#include <unistd.h>
#include "base/logging.h"
#include "base/macros.h"
#include "base/posix/eintr_wrapper.h"
// See the comments in dir_reader_posix.h about this.
namespace base {
struct linux_dirent {
uint64_t d_ino;
int64_t d_off;
unsigned short d_reclen;
unsigned char d_type;
char d_name[0];
};
class DirReaderLinux {
public:
explicit DirReaderLinux(const char* directory_path)
: fd_(open(directory_path, O_RDONLY | O_DIRECTORY)),
offset_(0),
size_(0) {
memset(buf_, 0, sizeof(buf_));
}
~DirReaderLinux() {
if (fd_ >= 0) {
if (IGNORE_EINTR(close(fd_)))
RAW_LOG(ERROR, "Failed to close directory handle");
}
}
bool IsValid() const {
return fd_ >= 0;
}
// Move to the next entry returning false if the iteration is complete.
bool Next() {
if (size_) {
linux_dirent* dirent = reinterpret_cast<linux_dirent*>(&buf_[offset_]);
offset_ += dirent->d_reclen;
}
if (offset_ != size_)
return true;
const int r = syscall(__NR_getdents64, fd_, buf_, sizeof(buf_));
if (r == 0)
return false;
if (r == -1) {
DPLOG(FATAL) << "getdents64 failed";
return false;
}
size_ = r;
offset_ = 0;
return true;
}
const char* name() const {
if (!size_)
return nullptr;
const linux_dirent* dirent =
reinterpret_cast<const linux_dirent*>(&buf_[offset_]);
return dirent->d_name;
}
int fd() const {
return fd_;
}
static bool IsFallback() {
return false;
}
private:
const int fd_;
alignas(linux_dirent) unsigned char buf_[512];
size_t offset_;
size_t size_;
DISALLOW_COPY_AND_ASSIGN(DirReaderLinux);
};
} // namespace base
#endif // BASE_FILES_DIR_READER_LINUX_H_