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// Copyright 2012 The Chromium Authors
// Use of this source code is governed by a BSD-style license that can be
// found in the LICENSE file.
#include "base/test/test_file_util.h"
#include <errno.h>
#include <fcntl.h>
#include <stddef.h>
#include <sys/types.h>
#include <unistd.h>
#include <string>
#include "base/check.h"
#include "base/check_op.h"
#include "base/files/file.h"
#include "base/files/file_util.h"
#include "base/notimplemented.h"
#include "base/strings/string_util.h"
#include "base/strings/utf_string_conversions.h"
#include "build/build_config.h"
namespace base {
namespace {
// Deny |permission| on the file |path|.
bool DenyFilePermission(const FilePath& path, mode_t permission) {
stat_wrapper_t stat_buf;
if (File::Stat(path, &stat_buf) != 0) {
return false;
}
stat_buf.st_mode &= ~permission;
int rv = HANDLE_EINTR(chmod(path.value().c_str(), stat_buf.st_mode));
return rv == 0;
}
// Gets a blob indicating the permission information for |path|.
// |length| is the length of the blob. Zero on failure.
// Returns the blob pointer, or NULL on failure.
void* GetPermissionInfo(const FilePath& path, size_t* length) {
DCHECK(length);
*length = 0;
stat_wrapper_t stat_buf;
if (File::Stat(path, &stat_buf) != 0) {
return nullptr;
}
*length = sizeof(mode_t);
mode_t* mode = new mode_t;
*mode = stat_buf.st_mode & ~S_IFMT; // Filter out file/path kind.
return mode;
}
// Restores the permission information for |path|, given the blob retrieved
// using |GetPermissionInfo()|.
// |info| is the pointer to the blob.
// |length| is the length of the blob.
// Either |info| or |length| may be NULL/0, in which case nothing happens.
bool RestorePermissionInfo(const FilePath& path, void* info, size_t length) {
if (!info || (length == 0)) {
return false;
}
DCHECK_EQ(sizeof(mode_t), length);
mode_t* mode = reinterpret_cast<mode_t*>(info);
int rv = HANDLE_EINTR(chmod(path.value().c_str(), *mode));
delete mode;
return rv == 0;
}
} // namespace
bool DieFileDie(const FilePath& file, bool recurse) {
// There is no need to workaround Windows problems on POSIX.
// Just pass-through.
if (recurse) {
return DeletePathRecursively(file);
}
return DeleteFile(file);
}
void SyncPageCacheToDisk() {
// On Linux (and Android) the sync(2) call waits for I/O completions.
sync();
}
#if !BUILDFLAG(IS_LINUX) && !BUILDFLAG(IS_CHROMEOS) && !BUILDFLAG(IS_APPLE) && \
!BUILDFLAG(IS_ANDROID)
bool EvictFileFromSystemCache(const FilePath& file) {
// There doesn't seem to be a POSIX way to cool the disk cache.
NOTIMPLEMENTED();
return false;
}
#endif
bool MakeFileUnreadable(const FilePath& path) {
return DenyFilePermission(path, S_IRUSR | S_IRGRP | S_IROTH);
}
bool MakeFileUnwritable(const FilePath& path) {
return DenyFilePermission(path, S_IWUSR | S_IWGRP | S_IWOTH);
}
FilePermissionRestorer::FilePermissionRestorer(const FilePath& path)
: path_(path), info_(nullptr), length_(0) {
info_ = GetPermissionInfo(path_, &length_);
DCHECK(info_ != nullptr);
DCHECK_NE(0u, length_);
}
FilePermissionRestorer::~FilePermissionRestorer() {
const bool success = RestorePermissionInfo(path_, info_, length_);
CHECK(success);
}
} // namespace base
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