// Copyright 2019 The MediaPipe Authors. // // 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 "mediapipe/framework/deps/file_path.h" #include "absl/strings/str_cat.h" namespace mediapipe { namespace file { // 40% of the time in JoinPath() is from calls with 2 arguments, so we // specialize that case. std::string JoinPath(absl::string_view path1, absl::string_view path2) { if (path1.empty()) return std::string(path2); if (path2.empty()) return std::string(path1); if (path1.back() == '/') { if (path2.front() == '/') return absl::StrCat(path1, absl::ClippedSubstr(path2, 1)); } else { if (path2.front() != '/') return absl::StrCat(path1, "/", path2); } return absl::StrCat(path1, path2); } namespace internal { // Given a collection of file paths, append them all together, // ensuring that the proper path separators are inserted between them. std::string JoinPathImpl(bool honor_abs, std::initializer_list paths) { std::string result; if (paths.size() != 0) { // This size calculation is worst-case: it assumes one extra "/" for every // path other than the first. size_t total_size = paths.size() - 1; for (const absl::string_view path : paths) total_size += path.size(); result.resize(total_size); auto begin = result.begin(); auto out = begin; bool trailing_slash = false; for (absl::string_view path : paths) { if (path.empty()) continue; if (path.front() == '/') { if (honor_abs) { out = begin; // wipe out whatever we've built up so far. } else if (trailing_slash) { path.remove_prefix(1); } } else { if (!trailing_slash && out != begin) *out++ = '/'; } const size_t this_size = path.size(); memcpy(&*out, path.data(), this_size); out += this_size; trailing_slash = out[-1] == '/'; } result.erase(out - begin); } return result; } // Return the parts of the basename of path, split on the final ".". // If there is no "." in the basename or "." is the final character in the // basename, the second value will be empty. std::pair SplitBasename( absl::string_view path) { path = Basename(path); absl::string_view::size_type pos = path.find_last_of('.'); if (pos == absl::string_view::npos) return std::make_pair(path, absl::ClippedSubstr(path, path.size(), 0)); return std::make_pair(path.substr(0, pos), absl::ClippedSubstr(path, pos + 1)); } } // namespace internal absl::string_view Dirname(absl::string_view path) { return SplitPath(path).first; } absl::string_view Basename(absl::string_view path) { return SplitPath(path).second; } std::pair SplitPath( absl::string_view path) { absl::string_view::size_type pos = path.find_last_of('/'); // Handle the case with no '/' in 'path'. if (pos == absl::string_view::npos) return std::make_pair(path.substr(0, 0), path); // Handle the case with a single leading '/' in 'path'. if (pos == 0) return std::make_pair(path.substr(0, 1), absl::ClippedSubstr(path, 1)); return std::make_pair(path.substr(0, pos), absl::ClippedSubstr(path, pos + 1)); } absl::string_view Extension(absl::string_view path) { return internal::SplitBasename(path).second; } } // namespace file } // namespace mediapipe