diff options
Diffstat (limited to 'base/file.cpp')
| -rw-r--r-- | base/file.cpp | 522 |
1 files changed, 0 insertions, 522 deletions
diff --git a/base/file.cpp b/base/file.cpp deleted file mode 100644 index 97cc2b27f7..0000000000 --- a/base/file.cpp +++ /dev/null @@ -1,522 +0,0 @@ -/* - * Copyright (C) 2015 The Android Open Source Project - * - * 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 "android-base/file.h" - -#include <errno.h> -#include <fcntl.h> -#include <ftw.h> -#include <libgen.h> -#include <stdio.h> -#include <stdlib.h> -#include <string.h> -#include <sys/stat.h> -#include <sys/types.h> -#include <unistd.h> - -#include <memory> -#include <mutex> -#include <string> -#include <vector> - -#if defined(__APPLE__) -#include <mach-o/dyld.h> -#endif -#if defined(_WIN32) -#include <direct.h> -#include <windows.h> -#define O_NOFOLLOW 0 -#define OS_PATH_SEPARATOR '\\' -#else -#define OS_PATH_SEPARATOR '/' -#endif - -#include "android-base/logging.h" // and must be after windows.h for ERROR -#include "android-base/macros.h" // For TEMP_FAILURE_RETRY on Darwin. -#include "android-base/unique_fd.h" -#include "android-base/utf8.h" - -namespace { - -#ifdef _WIN32 -static int mkstemp(char* name_template, size_t size_in_chars) { - std::wstring path; - CHECK(android::base::UTF8ToWide(name_template, &path)) - << "path can't be converted to wchar: " << name_template; - if (_wmktemp_s(path.data(), path.size() + 1) != 0) { - return -1; - } - - // Use open() to match the close() that TemporaryFile's destructor does. - // Use O_BINARY to match base file APIs. - int fd = _wopen(path.c_str(), O_CREAT | O_EXCL | O_RDWR | O_BINARY, S_IRUSR | S_IWUSR); - if (fd < 0) { - return -1; - } - - std::string path_utf8; - CHECK(android::base::WideToUTF8(path, &path_utf8)) << "path can't be converted to utf8"; - CHECK(strcpy_s(name_template, size_in_chars, path_utf8.c_str()) == 0) - << "utf8 path can't be assigned back to name_template"; - - return fd; -} - -static char* mkdtemp(char* name_template, size_t size_in_chars) { - std::wstring path; - CHECK(android::base::UTF8ToWide(name_template, &path)) - << "path can't be converted to wchar: " << name_template; - - if (_wmktemp_s(path.data(), path.size() + 1) != 0) { - return nullptr; - } - - if (_wmkdir(path.c_str()) != 0) { - return nullptr; - } - - std::string path_utf8; - CHECK(android::base::WideToUTF8(path, &path_utf8)) << "path can't be converted to utf8"; - CHECK(strcpy_s(name_template, size_in_chars, path_utf8.c_str()) == 0) - << "utf8 path can't be assigned back to name_template"; - - return name_template; -} -#endif - -std::string GetSystemTempDir() { -#if defined(__ANDROID__) - const auto* tmpdir = getenv("TMPDIR"); - if (tmpdir == nullptr) tmpdir = "/data/local/tmp"; - if (access(tmpdir, R_OK | W_OK | X_OK) == 0) { - return tmpdir; - } - // Tests running in app context can't access /data/local/tmp, - // so try current directory if /data/local/tmp is not accessible. - return "."; -#elif defined(_WIN32) - wchar_t tmp_dir_w[MAX_PATH]; - DWORD result = GetTempPathW(std::size(tmp_dir_w), tmp_dir_w); // checks TMP env - CHECK_NE(result, 0ul) << "GetTempPathW failed, error: " << GetLastError(); - CHECK_LT(result, std::size(tmp_dir_w)) << "path truncated to: " << result; - - // GetTempPath() returns a path with a trailing slash, but init() - // does not expect that, so remove it. - if (tmp_dir_w[result - 1] == L'\\') { - tmp_dir_w[result - 1] = L'\0'; - } - - std::string tmp_dir; - CHECK(android::base::WideToUTF8(tmp_dir_w, &tmp_dir)) << "path can't be converted to utf8"; - - return tmp_dir; -#else - const auto* tmpdir = getenv("TMPDIR"); - if (tmpdir == nullptr) tmpdir = "/tmp"; - return tmpdir; -#endif -} - -} // namespace - -TemporaryFile::TemporaryFile() { - init(GetSystemTempDir()); -} - -TemporaryFile::TemporaryFile(const std::string& tmp_dir) { - init(tmp_dir); -} - -TemporaryFile::~TemporaryFile() { - if (fd != -1) { - close(fd); - } - if (remove_file_) { - unlink(path); - } -} - -int TemporaryFile::release() { - int result = fd; - fd = -1; - return result; -} - -void TemporaryFile::init(const std::string& tmp_dir) { - snprintf(path, sizeof(path), "%s%cTemporaryFile-XXXXXX", tmp_dir.c_str(), OS_PATH_SEPARATOR); -#if defined(_WIN32) - fd = mkstemp(path, sizeof(path)); -#else - fd = mkstemp(path); -#endif -} - -TemporaryDir::TemporaryDir() { - init(GetSystemTempDir()); -} - -TemporaryDir::~TemporaryDir() { - if (!remove_dir_and_contents_) return; - - auto callback = [](const char* child, const struct stat*, int file_type, struct FTW*) -> int { - switch (file_type) { - case FTW_D: - case FTW_DP: - case FTW_DNR: - if (rmdir(child) == -1) { - PLOG(ERROR) << "rmdir " << child; - } - break; - case FTW_NS: - default: - if (rmdir(child) != -1) break; - // FALLTHRU (for gcc, lint, pcc, etc; and following for clang) - FALLTHROUGH_INTENDED; - case FTW_F: - case FTW_SL: - case FTW_SLN: - if (unlink(child) == -1) { - PLOG(ERROR) << "unlink " << child; - } - break; - } - return 0; - }; - - nftw(path, callback, 128, FTW_DEPTH | FTW_MOUNT | FTW_PHYS); -} - -bool TemporaryDir::init(const std::string& tmp_dir) { - snprintf(path, sizeof(path), "%s%cTemporaryDir-XXXXXX", tmp_dir.c_str(), OS_PATH_SEPARATOR); -#if defined(_WIN32) - return (mkdtemp(path, sizeof(path)) != nullptr); -#else - return (mkdtemp(path) != nullptr); -#endif -} - -namespace android { -namespace base { - -// Versions of standard library APIs that support UTF-8 strings. -using namespace android::base::utf8; - -bool ReadFdToString(borrowed_fd fd, std::string* content) { - content->clear(); - - // Although original we had small files in mind, this code gets used for - // very large files too, where the std::string growth heuristics might not - // be suitable. https://code.google.com/p/android/issues/detail?id=258500. - struct stat sb; - if (fstat(fd.get(), &sb) != -1 && sb.st_size > 0) { - content->reserve(sb.st_size); - } - - char buf[BUFSIZ] __attribute__((__uninitialized__)); - ssize_t n; - while ((n = TEMP_FAILURE_RETRY(read(fd.get(), &buf[0], sizeof(buf)))) > 0) { - content->append(buf, n); - } - return (n == 0) ? true : false; -} - -bool ReadFileToString(const std::string& path, std::string* content, bool follow_symlinks) { - content->clear(); - - int flags = O_RDONLY | O_CLOEXEC | O_BINARY | (follow_symlinks ? 0 : O_NOFOLLOW); - android::base::unique_fd fd(TEMP_FAILURE_RETRY(open(path.c_str(), flags))); - if (fd == -1) { - return false; - } - return ReadFdToString(fd, content); -} - -bool WriteStringToFd(const std::string& content, borrowed_fd fd) { - const char* p = content.data(); - size_t left = content.size(); - while (left > 0) { - ssize_t n = TEMP_FAILURE_RETRY(write(fd.get(), p, left)); - if (n == -1) { - return false; - } - p += n; - left -= n; - } - return true; -} - -static bool CleanUpAfterFailedWrite(const std::string& path) { - // Something went wrong. Let's not leave a corrupt file lying around. - int saved_errno = errno; - unlink(path.c_str()); - errno = saved_errno; - return false; -} - -#if !defined(_WIN32) -bool WriteStringToFile(const std::string& content, const std::string& path, - mode_t mode, uid_t owner, gid_t group, - bool follow_symlinks) { - int flags = O_WRONLY | O_CREAT | O_TRUNC | O_CLOEXEC | O_BINARY | - (follow_symlinks ? 0 : O_NOFOLLOW); - android::base::unique_fd fd(TEMP_FAILURE_RETRY(open(path.c_str(), flags, mode))); - if (fd == -1) { - PLOG(ERROR) << "android::WriteStringToFile open failed"; - return false; - } - - // We do an explicit fchmod here because we assume that the caller really - // meant what they said and doesn't want the umask-influenced mode. - if (fchmod(fd, mode) == -1) { - PLOG(ERROR) << "android::WriteStringToFile fchmod failed"; - return CleanUpAfterFailedWrite(path); - } - if (fchown(fd, owner, group) == -1) { - PLOG(ERROR) << "android::WriteStringToFile fchown failed"; - return CleanUpAfterFailedWrite(path); - } - if (!WriteStringToFd(content, fd)) { - PLOG(ERROR) << "android::WriteStringToFile write failed"; - return CleanUpAfterFailedWrite(path); - } - return true; -} -#endif - -bool WriteStringToFile(const std::string& content, const std::string& path, - bool follow_symlinks) { - int flags = O_WRONLY | O_CREAT | O_TRUNC | O_CLOEXEC | O_BINARY | - (follow_symlinks ? 0 : O_NOFOLLOW); - android::base::unique_fd fd(TEMP_FAILURE_RETRY(open(path.c_str(), flags, 0666))); - if (fd == -1) { - return false; - } - return WriteStringToFd(content, fd) || CleanUpAfterFailedWrite(path); -} - -bool ReadFully(borrowed_fd fd, void* data, size_t byte_count) { - uint8_t* p = reinterpret_cast<uint8_t*>(data); - size_t remaining = byte_count; - while (remaining > 0) { - ssize_t n = TEMP_FAILURE_RETRY(read(fd.get(), p, remaining)); - if (n <= 0) return false; - p += n; - remaining -= n; - } - return true; -} - -#if defined(_WIN32) -// Windows implementation of pread. Note that this DOES move the file descriptors read position, -// but it does so atomically. -static ssize_t pread(borrowed_fd fd, void* data, size_t byte_count, off64_t offset) { - DWORD bytes_read; - OVERLAPPED overlapped; - memset(&overlapped, 0, sizeof(OVERLAPPED)); - overlapped.Offset = static_cast<DWORD>(offset); - overlapped.OffsetHigh = static_cast<DWORD>(offset >> 32); - if (!ReadFile(reinterpret_cast<HANDLE>(_get_osfhandle(fd.get())), data, - static_cast<DWORD>(byte_count), &bytes_read, &overlapped)) { - // In case someone tries to read errno (since this is masquerading as a POSIX call) - errno = EIO; - return -1; - } - return static_cast<ssize_t>(bytes_read); -} -#endif - -bool ReadFullyAtOffset(borrowed_fd fd, void* data, size_t byte_count, off64_t offset) { - uint8_t* p = reinterpret_cast<uint8_t*>(data); - while (byte_count > 0) { - ssize_t n = TEMP_FAILURE_RETRY(pread(fd.get(), p, byte_count, offset)); - if (n <= 0) return false; - p += n; - byte_count -= n; - offset += n; - } - return true; -} - -bool WriteFully(borrowed_fd fd, const void* data, size_t byte_count) { - const uint8_t* p = reinterpret_cast<const uint8_t*>(data); - size_t remaining = byte_count; - while (remaining > 0) { - ssize_t n = TEMP_FAILURE_RETRY(write(fd.get(), p, remaining)); - if (n == -1) return false; - p += n; - remaining -= n; - } - return true; -} - -bool RemoveFileIfExists(const std::string& path, std::string* err) { - struct stat st; -#if defined(_WIN32) - // TODO: Windows version can't handle symbolic links correctly. - int result = stat(path.c_str(), &st); - bool file_type_removable = (result == 0 && S_ISREG(st.st_mode)); -#else - int result = lstat(path.c_str(), &st); - bool file_type_removable = (result == 0 && (S_ISREG(st.st_mode) || S_ISLNK(st.st_mode))); -#endif - if (result == -1) { - if (errno == ENOENT || errno == ENOTDIR) return true; - if (err != nullptr) *err = strerror(errno); - return false; - } - - if (result == 0) { - if (!file_type_removable) { - if (err != nullptr) { - *err = "is not a regular file or symbolic link"; - } - return false; - } - if (unlink(path.c_str()) == -1) { - if (err != nullptr) { - *err = strerror(errno); - } - return false; - } - } - return true; -} - -#if !defined(_WIN32) -bool Readlink(const std::string& path, std::string* result) { - result->clear(); - - // Most Linux file systems (ext2 and ext4, say) limit symbolic links to - // 4095 bytes. Since we'll copy out into the string anyway, it doesn't - // waste memory to just start there. We add 1 so that we can recognize - // whether it actually fit (rather than being truncated to 4095). - std::vector<char> buf(4095 + 1); - while (true) { - ssize_t size = readlink(path.c_str(), &buf[0], buf.size()); - // Unrecoverable error? - if (size == -1) return false; - // It fit! (If size == buf.size(), it may have been truncated.) - if (static_cast<size_t>(size) < buf.size()) { - result->assign(&buf[0], size); - return true; - } - // Double our buffer and try again. - buf.resize(buf.size() * 2); - } -} -#endif - -#if !defined(_WIN32) -bool Realpath(const std::string& path, std::string* result) { - result->clear(); - - // realpath may exit with EINTR. Retry if so. - char* realpath_buf = nullptr; - do { - realpath_buf = realpath(path.c_str(), nullptr); - } while (realpath_buf == nullptr && errno == EINTR); - - if (realpath_buf == nullptr) { - return false; - } - result->assign(realpath_buf); - free(realpath_buf); - return true; -} -#endif - -std::string GetExecutablePath() { -#if defined(__linux__) - std::string path; - android::base::Readlink("/proc/self/exe", &path); - return path; -#elif defined(__APPLE__) - char path[PATH_MAX + 1]; - uint32_t path_len = sizeof(path); - int rc = _NSGetExecutablePath(path, &path_len); - if (rc < 0) { - std::unique_ptr<char> path_buf(new char[path_len]); - _NSGetExecutablePath(path_buf.get(), &path_len); - return path_buf.get(); - } - return path; -#elif defined(_WIN32) - char path[PATH_MAX + 1]; - DWORD result = GetModuleFileName(NULL, path, sizeof(path) - 1); - if (result == 0 || result == sizeof(path) - 1) return ""; - path[PATH_MAX - 1] = 0; - return path; -#else -#error unknown OS -#endif -} - -std::string GetExecutableDirectory() { - return Dirname(GetExecutablePath()); -} - -std::string Basename(const std::string& path) { - // Copy path because basename may modify the string passed in. - std::string result(path); - -#if !defined(__BIONIC__) - // Use lock because basename() may write to a process global and return a - // pointer to that. Note that this locking strategy only works if all other - // callers to basename in the process also grab this same lock, but its - // better than nothing. Bionic's basename returns a thread-local buffer. - static std::mutex& basename_lock = *new std::mutex(); - std::lock_guard<std::mutex> lock(basename_lock); -#endif - - // Note that if std::string uses copy-on-write strings, &str[0] will cause - // the copy to be made, so there is no chance of us accidentally writing to - // the storage for 'path'. - char* name = basename(&result[0]); - - // In case basename returned a pointer to a process global, copy that string - // before leaving the lock. - result.assign(name); - - return result; -} - -std::string Dirname(const std::string& path) { - // Copy path because dirname may modify the string passed in. - std::string result(path); - -#if !defined(__BIONIC__) - // Use lock because dirname() may write to a process global and return a - // pointer to that. Note that this locking strategy only works if all other - // callers to dirname in the process also grab this same lock, but its - // better than nothing. Bionic's dirname returns a thread-local buffer. - static std::mutex& dirname_lock = *new std::mutex(); - std::lock_guard<std::mutex> lock(dirname_lock); -#endif - - // Note that if std::string uses copy-on-write strings, &str[0] will cause - // the copy to be made, so there is no chance of us accidentally writing to - // the storage for 'path'. - char* parent = dirname(&result[0]); - - // In case dirname returned a pointer to a process global, copy that string - // before leaving the lock. - result.assign(parent); - - return result; -} - -} // namespace base -} // namespace android |