chromium/third_party/crashpad/crashpad/test/filesystem.cc

// Copyright 2017 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 "test/filesystem.h"

#include <errno.h>
#include <fcntl.h>
#include <sys/stat.h>
#include <sys/time.h>
#include <sys/types.h>

#include "base/logging.h"
#include "base/strings/utf_string_conversions.h"
#include "build/build_config.h"
#include "gtest/gtest.h"
#include "test/errors.h"
#include "test/scoped_temp_dir.h"
#include "util/file/file_io.h"
#include "util/file/filesystem.h"
#include "util/misc/time.h"

#if BUILDFLAG(IS_POSIX)
#include <unistd.h>

#include "base/posix/eintr_wrapper.h"
#elif BUILDFLAG(IS_WIN)
#include <windows.h>
#endif

namespace crashpad {
namespace test {

namespace {

#if BUILDFLAG(IS_WIN)

// Detects the flags necessary to create symbolic links and stores them in
// |flags| if non-nullptr, and returns true on success. If symbolic links can’t
// be created, returns false.
bool SymbolicLinkFlags(DWORD* flags) {
  static DWORD symbolic_link_flags = []() {
    ScopedTempDir temp_dir_;

    base::FilePath target_path = temp_dir_.path().Append(L"target");
    base::FilePath symlink_path = temp_dir_.path().Append(L"symlink");
    if (::CreateSymbolicLink(
            symlink_path.value().c_str(), target_path.value().c_str(), 0)) {
      return 0;
    }

    DWORD error = GetLastError();
    if (error == ERROR_PRIVILEGE_NOT_HELD) {
      if (::CreateSymbolicLink(symlink_path.value().c_str(),
                               target_path.value().c_str(),
                               SYMBOLIC_LINK_FLAG_ALLOW_UNPRIVILEGED_CREATE)) {
        return SYMBOLIC_LINK_FLAG_ALLOW_UNPRIVILEGED_CREATE;
      }

      // This may fail with ERROR_INVALID_PARAMETER if the OS is too old to
      // understand SYMBOLIC_LINK_FLAG_ALLOW_UNPRIVILEGED_CREATE, so keep
      // ERROR_PRIVILEGE_NOT_HELD for |error|.
    }

    // Don’t use ErrorMessage() here because the second CreateSymbolicLink() may
    // have scrambled it. Use the saved |error| value instead.
    EXPECT_EQ(error, static_cast<DWORD>(ERROR_PRIVILEGE_NOT_HELD))
        << "CreateSymbolicLink: " << logging::SystemErrorCodeToString(error);
    return -1;
  }();

  if (symbolic_link_flags == static_cast<DWORD>(-1)) {
    return false;
  }

  if (flags) {
    *flags = symbolic_link_flags;
  }

  return true;
}

#endif  // BUILDFLAG(IS_WIN)

}  // namespace

bool CreateFile(const base::FilePath& file) { … }

bool PathExists(const base::FilePath& path) { … }

bool SetFileModificationTime(const base::FilePath& path,
                             const timespec& mtime) { … }

#if !BUILDFLAG(IS_FUCHSIA)

bool CanCreateSymbolicLinks() { … }

bool CreateSymbolicLink(const base::FilePath& target_path,
                        const base::FilePath& symlink_path) { … }

#endif  // !BUILDFLAG(IS_FUCHSIA)

}  // namespace test
}  // namespace crashpad