blob: 7043b756ae2af60b3c39545778f9726643705f26 [file] [log] [blame]
// 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.
#include "base/files/file_util.h"
#if defined(OS_WIN)
#include <io.h>
#endif
#include <stdio.h>
#include <fstream>
#include <limits>
#include <string_view>
#include "base/files/file_enumerator.h"
#include "base/files/file_path.h"
#include "base/logging.h"
#include "base/strings/string_util.h"
#include "base/strings/stringprintf.h"
#include "base/strings/utf_string_conversions.h"
#include "util/build_config.h"
namespace base {
namespace {
// The maximum number of 'uniquified' files we will try to create.
// This is used when the filename we're trying to download is already in use,
// so we create a new unique filename by appending " (nnn)" before the
// extension, where 1 <= nnn <= kMaxUniqueFiles.
// Also used by code that cleans up said files.
static const int kMaxUniqueFiles = 100;
} // namespace
int64_t ComputeDirectorySize(const FilePath& root_path) {
int64_t running_size = 0;
FileEnumerator file_iter(root_path, true, FileEnumerator::FILES);
while (!file_iter.Next().empty())
running_size += file_iter.GetInfo().GetSize();
return running_size;
}
bool ContentsEqual(const FilePath& filename1, const FilePath& filename2) {
// We open the file in binary format even if they are text files because
// we are just comparing that bytes are exactly same in both files and not
// doing anything smart with text formatting.
std::ifstream file1(filename1.As8Bit().c_str(),
std::ios::in | std::ios::binary);
std::ifstream file2(filename2.As8Bit().c_str(),
std::ios::in | std::ios::binary);
// Even if both files aren't openable (and thus, in some sense, "equal"),
// any unusable file yields a result of "false".
if (!file1.is_open() || !file2.is_open())
return false;
const int BUFFER_SIZE = 2056;
char buffer1[BUFFER_SIZE], buffer2[BUFFER_SIZE];
do {
file1.read(buffer1, BUFFER_SIZE);
file2.read(buffer2, BUFFER_SIZE);
if ((file1.eof() != file2.eof()) || (file1.gcount() != file2.gcount()) ||
(memcmp(buffer1, buffer2, static_cast<size_t>(file1.gcount())))) {
file1.close();
file2.close();
return false;
}
} while (!file1.eof() || !file2.eof());
file1.close();
file2.close();
return true;
}
bool TextContentsEqual(const FilePath& filename1, const FilePath& filename2) {
std::ifstream file1(filename1.As8Bit().c_str(), std::ios::in);
std::ifstream file2(filename2.As8Bit().c_str(), std::ios::in);
// Even if both files aren't openable (and thus, in some sense, "equal"),
// any unusable file yields a result of "false".
if (!file1.is_open() || !file2.is_open())
return false;
do {
std::string line1, line2;
getline(file1, line1);
getline(file2, line2);
// Check for mismatched EOF states, or any error state.
if ((file1.eof() != file2.eof()) || file1.bad() || file2.bad()) {
return false;
}
// Trim all '\r' and '\n' characters from the end of the line.
std::string::size_type end1 = line1.find_last_not_of("\r\n");
if (end1 == std::string::npos)
line1.clear();
else if (end1 + 1 < line1.length())
line1.erase(end1 + 1);
std::string::size_type end2 = line2.find_last_not_of("\r\n");
if (end2 == std::string::npos)
line2.clear();
else if (end2 + 1 < line2.length())
line2.erase(end2 + 1);
if (line1 != line2)
return false;
} while (!file1.eof() || !file2.eof());
return true;
}
bool ReadFileToStringWithMaxSize(const FilePath& path,
std::string* contents,
size_t max_size) {
if (contents)
contents->clear();
if (path.ReferencesParent())
return false;
FILE* file = OpenFile(path, "rb");
if (!file) {
return false;
}
// Many files supplied in |path| have incorrect size (proc files etc).
// Hence, the file is read sequentially as opposed to a one-shot read, using
// file size as a hint for chunk size if available.
constexpr int64_t kDefaultChunkSize = 1 << 16;
int64_t chunk_size;
if (!GetFileSize(path, &chunk_size) || chunk_size <= 0)
chunk_size = kDefaultChunkSize - 1;
// We need to attempt to read at EOF for feof flag to be set so here we
// use |chunk_size| + 1.
chunk_size = std::min<uint64_t>(chunk_size, max_size) + 1;
size_t bytes_read_this_pass;
size_t bytes_read_so_far = 0;
bool read_status = true;
std::string local_contents;
local_contents.resize(chunk_size);
while ((bytes_read_this_pass = fread(&local_contents[bytes_read_so_far], 1,
chunk_size, file)) > 0) {
if ((max_size - bytes_read_so_far) < bytes_read_this_pass) {
// Read more than max_size bytes, bail out.
bytes_read_so_far = max_size;
read_status = false;
break;
}
// In case EOF was not reached, iterate again but revert to the default
// chunk size.
if (bytes_read_so_far == 0)
chunk_size = kDefaultChunkSize;
bytes_read_so_far += bytes_read_this_pass;
// Last fread syscall (after EOF) can be avoided via feof, which is just a
// flag check.
if (feof(file))
break;
local_contents.resize(bytes_read_so_far + chunk_size);
}
read_status = read_status && !ferror(file);
CloseFile(file);
if (contents) {
contents->swap(local_contents);
contents->resize(bytes_read_so_far);
}
return read_status;
}
bool ReadFileToString(const FilePath& path, std::string* contents) {
return ReadFileToStringWithMaxSize(path, contents,
std::numeric_limits<size_t>::max());
}
bool IsDirectoryEmpty(const FilePath& dir_path) {
FileEnumerator files(dir_path, false,
FileEnumerator::FILES | FileEnumerator::DIRECTORIES);
if (files.Next().empty())
return true;
return false;
}
FILE* CreateAndOpenTemporaryFile(FilePath* path) {
FilePath directory;
if (!GetTempDir(&directory))
return nullptr;
return CreateAndOpenTemporaryFileInDir(directory, path);
}
bool CreateDirectory(const FilePath& full_path) {
return CreateDirectoryAndGetError(full_path, nullptr);
}
bool GetFileSize(const FilePath& file_path, int64_t* file_size) {
File::Info info;
if (!GetFileInfo(file_path, &info))
return false;
*file_size = info.size;
return true;
}
bool CloseFile(FILE* file) {
if (file == nullptr)
return true;
return fclose(file) == 0;
}
bool TruncateFile(FILE* file) {
if (file == nullptr)
return false;
long current_offset = ftell(file);
if (current_offset == -1)
return false;
#if defined(OS_WIN)
int fd = _fileno(file);
if (_chsize(fd, current_offset) != 0)
return false;
#else
int fd = fileno(file);
if (ftruncate(fd, current_offset) != 0)
return false;
#endif
return true;
}
int GetUniquePathNumber(const FilePath& path,
const FilePath::StringType& suffix) {
bool have_suffix = !suffix.empty();
if (!PathExists(path) &&
(!have_suffix || !PathExists(FilePath(path.value() + suffix)))) {
return 0;
}
FilePath new_path;
for (int count = 1; count <= kMaxUniqueFiles; ++count) {
new_path = path.InsertBeforeExtensionASCII(StringPrintf(" (%d)", count));
if (!PathExists(new_path) &&
(!have_suffix || !PathExists(FilePath(new_path.value() + suffix)))) {
return count;
}
}
return -1;
}
} // namespace base