spdlog/details/file_helper-inl.h

0001 // Copyright(c) 2015-present, Gabi Melman & spdlog contributors.
0002 // Distributed under the MIT License (http://opensource.org/licenses/MIT)
0003
0004 #pragma once
0005
0006 #ifndef SPDLOG_HEADER_ONLY
0007     #include <spdlog/details/file_helper.h>
0008 #endif
0009
0010 #include <spdlog/common.h>
0011 #include <spdlog/details/os.h>
0012
0013 #include <cerrno>
0014 #include <chrono>
0015 #include <cstdio>
0016 #include <string>
0017 #include <thread>
0018 #include <tuple>
0019
0020 namespace spdlog {
0021 namespace details {
0022
0023 SPDLOG_INLINE file_helper::file_helper(const file_event_handlers &event_handlers)
0024     : event_handlers_(event_handlers) {}
0025
0026 SPDLOG_INLINE file_helper::~file_helper() { close(); }
0027
0028 SPDLOG_INLINE void file_helper::open(const filename_t &fname, bool truncate) {
0029     close();
0030     filename_ = fname;
0031
0032     auto *mode = SPDLOG_FILENAME_T("ab");
0033     auto *trunc_mode = SPDLOG_FILENAME_T("wb");
0034
0035     if (event_handlers_.before_open) {
0036         event_handlers_.before_open(filename_);
0037     }
0038     for (int tries = 0; tries < open_tries_; ++tries) {
0039         // create containing folder if not exists already.
0040         os::create_dir(os::dir_name(fname));
0041         if (truncate) {
0042             // Truncate by opening-and-closing a tmp file in "wb" mode, always
0043             // opening the actual log-we-write-to in "ab" mode, since that
0044             // interacts more politely with eternal processes that might
0045             // rotate/truncate the file underneath us.
0046             std::FILE *tmp;
0047             if (os::fopen_s(&tmp, fname, trunc_mode)) {
0048                 continue;
0049             }
0050             std::fclose(tmp);
0051         }
0052         if (!os::fopen_s(&fd_, fname, mode)) {
0053             if (event_handlers_.after_open) {
0054                 event_handlers_.after_open(filename_, fd_);
0055             }
0056             return;
0057         }
0058
0059         details::os::sleep_for_millis(open_interval_);
0060     }
0061
0062     throw_spdlog_ex("Failed opening file " + os::filename_to_str(filename_) + " for writing",
0063                     errno);
0064 }
0065
0066 SPDLOG_INLINE void file_helper::reopen(bool truncate) {
0067     if (filename_.empty()) {
0068         throw_spdlog_ex("Failed re opening file - was not opened before");
0069     }
0070     this->open(filename_, truncate);
0071 }
0072
0073 SPDLOG_INLINE void file_helper::flush() {
0074     if (std::fflush(fd_) != 0) {
0075         throw_spdlog_ex("Failed flush to file " + os::filename_to_str(filename_), errno);
0076     }
0077 }
0078
0079 SPDLOG_INLINE void file_helper::sync() {
0080     if (!os::fsync(fd_)) {
0081         throw_spdlog_ex("Failed to fsync file " + os::filename_to_str(filename_), errno);
0082     }
0083 }
0084
0085 SPDLOG_INLINE void file_helper::close() {
0086     if (fd_ != nullptr) {
0087         if (event_handlers_.before_close) {
0088             event_handlers_.before_close(filename_, fd_);
0089         }
0090
0091         std::fclose(fd_);
0092         fd_ = nullptr;
0093
0094         if (event_handlers_.after_close) {
0095             event_handlers_.after_close(filename_);
0096         }
0097     }
0098 }
0099
0100 SPDLOG_INLINE void file_helper::write(const memory_buf_t &buf) {
0101     if (fd_ == nullptr) return;
0102     size_t msg_size = buf.size();
0103     auto data = buf.data();
0104     if (std::fwrite(data, 1, msg_size, fd_) != msg_size) {
0105         throw_spdlog_ex("Failed writing to file " + os::filename_to_str(filename_), errno);
0106     }
0107 }
0108
0109 SPDLOG_INLINE size_t file_helper::size() const {
0110     if (fd_ == nullptr) {
0111         throw_spdlog_ex("Cannot use size() on closed file " + os::filename_to_str(filename_));
0112     }
0113     return os::filesize(fd_);
0114 }
0115
0116 SPDLOG_INLINE const filename_t &file_helper::filename() const { return filename_; }
0117
0118 //
0119 // return file path and its extension:
0120 //
0121 // "mylog.txt" => ("mylog", ".txt")
0122 // "mylog" => ("mylog", "")
0123 // "mylog." => ("mylog.", "")
0124 // "/dir1/dir2/mylog.txt" => ("/dir1/dir2/mylog", ".txt")
0125 //
0126 // the starting dot in filenames is ignored (hidden files):
0127 //
0128 // ".mylog" => (".mylog". "")
0129 // "my_folder/.mylog" => ("my_folder/.mylog", "")
0130 // "my_folder/.mylog.txt" => ("my_folder/.mylog", ".txt")
0131 SPDLOG_INLINE std::tuple<filename_t, filename_t> file_helper::split_by_extension(
0132     const filename_t &fname) {
0133     auto ext_index = fname.rfind('.');
0134
0135     // no valid extension found - return whole path and empty string as
0136     // extension
0137     if (ext_index == filename_t::npos || ext_index == 0 || ext_index == fname.size() - 1) {
0138         return std::make_tuple(fname, filename_t());
0139     }
0140
0141     // treat cases like "/etc/rc.d/somelogfile or "/abc/.hiddenfile"
0142     auto folder_index = fname.find_last_of(details::os::folder_seps_filename);
0143     if (folder_index != filename_t::npos && folder_index >= ext_index - 1) {
0144         return std::make_tuple(fname, filename_t());
0145     }
0146
0147     // finally - return a valid base and extension tuple
0148     return std::make_tuple(fname.substr(0, ext_index), fname.substr(ext_index));
0149 }
0150
0151 }  // namespace details
0152 }  // namespace spdlog