From dec12b2b71ec73483f9a2267ee5717d7eb0cdf6d Mon Sep 17 00:00:00 2001 From: Elliott Hughes Date: Mon, 2 Feb 2015 17:31:27 -0800 Subject: Add Google-style ReadFileToString and WriteStringToFile. Bug: 19217569 Change-Id: I64789d3fa6777ee30a324cdf00fdc275c1230e1b --- libutils/file.cpp | 68 +++++++++++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 68 insertions(+) create mode 100644 libutils/file.cpp (limited to 'libutils/file.cpp') diff --git a/libutils/file.cpp b/libutils/file.cpp new file mode 100644 index 0000000..15bda7f --- /dev/null +++ b/libutils/file.cpp @@ -0,0 +1,68 @@ +/* + * 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 "utils/file.h" + +#include +#include +#include +#include + +bool android::ReadFileToString(const std::string& path, std::string* content) { + content->clear(); + + int fd = TEMP_FAILURE_RETRY(open(path.c_str(), O_RDONLY | O_CLOEXEC | O_NOFOLLOW)); + if (fd == -1) { + return false; + } + + while (true) { + char buf[BUFSIZ]; + ssize_t n = TEMP_FAILURE_RETRY(read(fd, &buf[0], sizeof(buf))); + if (n == -1) { + TEMP_FAILURE_RETRY(close(fd)); + return false; + } + if (n == 0) { + TEMP_FAILURE_RETRY(close(fd)); + return true; + } + content->append(buf, n); + } +} + +bool android::WriteStringToFile(const std::string& content, const std::string& path) { + int fd = TEMP_FAILURE_RETRY(open(path.c_str(), + O_WRONLY | O_CREAT | O_TRUNC | O_CLOEXEC | O_NOFOLLOW, + DEFFILEMODE)); + if (fd == -1) { + return false; + } + + const char* p = content.data(); + size_t left = content.size(); + while (left > 0) { + ssize_t n = TEMP_FAILURE_RETRY(write(fd, p, left)); + if (n == -1) { + TEMP_FAILURE_RETRY(close(fd)); + return false; + } + p += n; + left -= n; + } + TEMP_FAILURE_RETRY(close(fd)); + return true; +} -- cgit v1.1