1 /*
2  * Copyright (c) Huawei Technologies Co., Ltd. 2021. All rights reserved.
3  * Licensed under the Apache License, Version 2.0 (the "License");
4  * you may not use this file except in compliance with the License.
5  * You may obtain a copy of the License at
6  *
7  *     http://www.apache.org/licenses/LICENSE-2.0
8  *
9  * Unless required by applicable law or agreed to in writing, software
10  * distributed under the License is distributed on an "AS IS" BASIS,
11  * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
12  * See the License for the specific language governing permissions and
13  * limitations under the License.
14  *
15  * Description: FileUtils implements
16  */
17 #include "file_utils.h"
18 
19 #include <cerrno>
20 #include <cstring>
21 #include <dirent.h>
22 #include <fcntl.h>
23 #include <unistd.h>
24 #include <regex>
25 #include "logging.h"
26 
27 namespace {
28 constexpr size_t DEFAULT_READ_SIZE = 4096;
29 }
30 
ReadFile(int fd)31 std::string FileUtils::ReadFile(int fd)
32 {
33     std::string content;
34     size_t count = 0;
35     while (true) {
36         if (content.size() - count < DEFAULT_READ_SIZE) {
37             content.resize(content.size() + DEFAULT_READ_SIZE);
38         }
39         ssize_t nBytes = TEMP_FAILURE_RETRY(read(fd, &content[count], content.size() - count));
40         if (nBytes == -1 && errno == EAGAIN) {
41             continue;
42         }
43         if (nBytes <= 0) {
44             break;
45         }
46         count += nBytes;
47     }
48     content.resize(count);
49     return content;
50 }
51 
ReadFile(const std::string& path)52 std::string FileUtils::ReadFile(const std::string& path)
53 {
54     char realPath[PATH_MAX + 1] = {0};
55     CHECK_TRUE((path.length() < PATH_MAX) && (realpath(path.c_str(), realPath) != nullptr), "",
56                "%s:path is invalid: %s, errno=%d", __func__, path.c_str(), errno);
57     int fd = open(realPath, O_RDONLY);
58     if (fd == -1) {
59         const int bufSize = 256;
60         char buf[bufSize] = { 0 };
61         strerror_r(errno, buf, bufSize);
62         PROFILER_LOG_WARN(LOG_CORE, "open file %s FAILED: %s!", path.c_str(), buf);
63         return "";
64     }
65     std::string content = ReadFile(fd);
66     CHECK_TRUE(close(fd) != -1, content, "close %s failed, %d", path.c_str(), errno);
67     return content;
68 }
69 
WriteFile(const std::string& path, const std::string& content)70 int FileUtils::WriteFile(const std::string& path, const std::string& content)
71 {
72     return WriteFile(path, content, O_WRONLY);
73 }
74 
WriteFile(const std::string& path, const std::string& content, int flags)75 int FileUtils::WriteFile(const std::string& path, const std::string& content, int flags)
76 {
77     return WriteFile(path, content, flags, 0);
78 }
79 
WriteFile(const std::string& path, const std::string& content, int flags, int mode)80 int FileUtils::WriteFile(const std::string& path, const std::string& content, int flags, int mode)
81 {
82     CHECK_TRUE(!path.empty() && (path.length() < PATH_MAX), -1,
83                "%s:path is invalid: %s, errno=%d", __func__, path.c_str(), errno);
84 
85     std::regex dirNameRegex("[.~-]");
86     std::regex fileNameRegex("[\\/:*?\"<>|]");
87     size_t pos = path.rfind("/");
88     if (pos != std::string::npos) {
89         std::string dirName = path.substr(0, pos+1);
90         size_t index = path.length() > (pos + 1) ? path.length() - pos - 1 : 0;
91         std::string fileName = path.substr(pos+1, index);
92         CHECK_TRUE(!(std::regex_search(dirName, dirNameRegex) || std::regex_search(fileName, fileNameRegex)), -1,
93                    "%s:path is invalid: %s, errno=%d", __func__, path.c_str(), errno);
94     } else {
95         CHECK_TRUE(!std::regex_search(path, fileNameRegex), -1,
96                    "%s:path is invalid: %s, errno=%d", __func__, path.c_str(), errno);
97     }
98 
99     int fd = open(path.c_str(), flags, mode);
100     CHECK_TRUE(fd >= 0, -1, "open %s failed, %d", path.c_str(), errno);
101 
102     int retval = write(fd, content.data(), content.size());
103     CHECK_TRUE(close(fd) != -1, -1, "close %s failed, %d", path.c_str(), errno);
104     return retval;
105 }
106 
ListDir(const std::string& dirPath)107 std::vector<std::string> FileUtils::ListDir(const std::string& dirPath)
108 {
109     std::vector<std::string> result;
110     DIR* dir = opendir(dirPath.c_str());
111     if (dir == nullptr) {
112         return result;
113     }
114 
115     struct dirent* ent = nullptr;
116     while ((ent = readdir(dir)) != nullptr) {
117         std::string name = ent->d_name;
118         if (name == "." || name == "..") {
119             continue;
120         }
121         result.push_back(name);
122     }
123     closedir(dir);
124     return result;
125 }
126