Nagram/TMessagesProj/jni/webrtc/base/files/file_enumerator_posix.cc
2020-08-14 19:58:22 +03:00

247 lines
8.2 KiB
C++

// Copyright (c) 2013 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/files/file_enumerator.h"
#include <dirent.h>
#include <errno.h>
#include <fnmatch.h>
#include <stdint.h>
#include <string.h>
#include "base/logging.h"
#include "base/threading/scoped_blocking_call.h"
#include "build/build_config.h"
namespace base {
namespace {
void GetStat(const FilePath& path, bool show_links, stat_wrapper_t* st) {
DCHECK(st);
const int res = show_links ? File::Lstat(path.value().c_str(), st)
: File::Stat(path.value().c_str(), st);
if (res < 0) {
// Print the stat() error message unless it was ENOENT and we're following
// symlinks.
if (!(errno == ENOENT && !show_links))
DPLOG(ERROR) << "Couldn't stat" << path.value();
memset(st, 0, sizeof(*st));
}
}
#if defined(OS_FUCHSIA)
bool ShouldShowSymLinks(int file_type) {
return false;
}
#else
bool ShouldShowSymLinks(int file_type) {
return file_type & FileEnumerator::SHOW_SYM_LINKS;
}
#endif // defined(OS_FUCHSIA)
#if defined(OS_FUCHSIA)
bool ShouldTrackVisitedDirectories(int file_type) {
return false;
}
#else
bool ShouldTrackVisitedDirectories(int file_type) {
return !(file_type & FileEnumerator::SHOW_SYM_LINKS);
}
#endif // defined(OS_FUCHSIA)
} // namespace
// FileEnumerator::FileInfo ----------------------------------------------------
FileEnumerator::FileInfo::FileInfo() {
memset(&stat_, 0, sizeof(stat_));
}
bool FileEnumerator::FileInfo::IsDirectory() const {
return S_ISDIR(stat_.st_mode);
}
FilePath FileEnumerator::FileInfo::GetName() const {
return filename_;
}
int64_t FileEnumerator::FileInfo::GetSize() const {
return stat_.st_size;
}
base::Time FileEnumerator::FileInfo::GetLastModifiedTime() const {
return base::Time::FromTimeT(stat_.st_mtime);
}
// FileEnumerator --------------------------------------------------------------
FileEnumerator::FileEnumerator(const FilePath& root_path,
bool recursive,
int file_type)
: FileEnumerator(root_path,
recursive,
file_type,
FilePath::StringType(),
FolderSearchPolicy::MATCH_ONLY) {}
FileEnumerator::FileEnumerator(const FilePath& root_path,
bool recursive,
int file_type,
const FilePath::StringType& pattern)
: FileEnumerator(root_path,
recursive,
file_type,
pattern,
FolderSearchPolicy::MATCH_ONLY) {}
FileEnumerator::FileEnumerator(const FilePath& root_path,
bool recursive,
int file_type,
const FilePath::StringType& pattern,
FolderSearchPolicy folder_search_policy)
: FileEnumerator(root_path,
recursive,
file_type,
pattern,
folder_search_policy,
ErrorPolicy::IGNORE_ERRORS) {}
FileEnumerator::FileEnumerator(const FilePath& root_path,
bool recursive,
int file_type,
const FilePath::StringType& pattern,
FolderSearchPolicy folder_search_policy,
ErrorPolicy error_policy)
: current_directory_entry_(0),
root_path_(root_path),
recursive_(recursive),
file_type_(file_type),
pattern_(pattern),
folder_search_policy_(folder_search_policy),
error_policy_(error_policy) {
// INCLUDE_DOT_DOT must not be specified if recursive.
DCHECK(!(recursive && (INCLUDE_DOT_DOT & file_type_)));
if (recursive && ShouldTrackVisitedDirectories(file_type_)) {
stat_wrapper_t st;
GetStat(root_path, false, &st);
visited_directories_.insert(st.st_ino);
}
pending_paths_.push(root_path);
}
FileEnumerator::~FileEnumerator() = default;
FilePath FileEnumerator::Next() {
ScopedBlockingCall scoped_blocking_call(FROM_HERE, BlockingType::MAY_BLOCK);
++current_directory_entry_;
// While we've exhausted the entries in the current directory, do the next
while (current_directory_entry_ >= directory_entries_.size()) {
if (pending_paths_.empty())
return FilePath();
root_path_ = pending_paths_.top();
root_path_ = root_path_.StripTrailingSeparators();
pending_paths_.pop();
DIR* dir = opendir(root_path_.value().c_str());
if (!dir) {
if (errno == 0 || error_policy_ == ErrorPolicy::IGNORE_ERRORS)
continue;
error_ = File::OSErrorToFileError(errno);
return FilePath();
}
directory_entries_.clear();
#if defined(OS_FUCHSIA)
// Fuchsia does not support .. on the file system server side, see
// https://fuchsia.googlesource.com/docs/+/master/dotdot.md and
// https://crbug.com/735540. However, for UI purposes, having the parent
// directory show up in directory listings makes sense, so we add it here to
// match the expectation on other operating systems. In cases where this
// is useful it should be resolvable locally.
FileInfo dotdot;
dotdot.stat_.st_mode = S_IFDIR;
dotdot.filename_ = FilePath("..");
if (!ShouldSkip(dotdot.filename_)) {
directory_entries_.push_back(std::move(dotdot));
}
#endif // OS_FUCHSIA
current_directory_entry_ = 0;
struct dirent* dent;
// NOTE: Per the readdir() documentation, when the end of the directory is
// reached with no errors, null is returned and errno is not changed.
// Therefore we must reset errno to zero before calling readdir() if we
// wish to know whether a null result indicates an error condition.
while (errno = 0, dent = readdir(dir)) {
FileInfo info;
info.filename_ = FilePath(dent->d_name);
if (ShouldSkip(info.filename_))
continue;
const bool is_pattern_matched = IsPatternMatched(info.filename_);
// MATCH_ONLY policy enumerates files and directories which matching
// pattern only. So we can early skip further checks.
if (folder_search_policy_ == FolderSearchPolicy::MATCH_ONLY &&
!is_pattern_matched)
continue;
// Do not call OS stat/lstat if there is no sense to do it. If pattern is
// not matched (file will not appear in results) and search is not
// recursive (possible directory will not be added to pending paths) -
// there is no sense to obtain item below.
if (!recursive_ && !is_pattern_matched)
continue;
const FilePath full_path = root_path_.Append(info.filename_);
GetStat(full_path, ShouldShowSymLinks(file_type_), &info.stat_);
const bool is_dir = info.IsDirectory();
// Recursive mode: schedule traversal of a directory if either
// SHOW_SYM_LINKS is on or we haven't visited the directory yet.
if (recursive_ && is_dir &&
(!ShouldTrackVisitedDirectories(file_type_) ||
visited_directories_.insert(info.stat_.st_ino).second)) {
pending_paths_.push(full_path);
}
if (is_pattern_matched && IsTypeMatched(is_dir))
directory_entries_.push_back(std::move(info));
}
int readdir_errno = errno;
closedir(dir);
if (readdir_errno != 0 && error_policy_ != ErrorPolicy::IGNORE_ERRORS) {
error_ = File::OSErrorToFileError(readdir_errno);
return FilePath();
}
// MATCH_ONLY policy enumerates files in matched subfolders by "*" pattern.
// ALL policy enumerates files in all subfolders by origin pattern.
if (folder_search_policy_ == FolderSearchPolicy::MATCH_ONLY)
pattern_.clear();
}
return root_path_.Append(
directory_entries_[current_directory_entry_].filename_);
}
FileEnumerator::FileInfo FileEnumerator::GetInfo() const {
return directory_entries_[current_directory_entry_];
}
bool FileEnumerator::IsPatternMatched(const FilePath& path) const {
return pattern_.empty() ||
!fnmatch(pattern_.c_str(), path.value().c_str(), FNM_NOESCAPE);
}
} // namespace base