kicad/thirdparty/sentry-native/external/libunwindstack-ndk/android-base/file.cpp

398 lines
12 KiB
C++

/*
* 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
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;
}
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