| /* |
| * Copyright (C) 2017 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. |
| */ |
| |
| #ifndef LIBTEXTCLASSIFIER_COMMON_FILE_UTILS_H_ |
| #define LIBTEXTCLASSIFIER_COMMON_FILE_UTILS_H_ |
| |
| #include <cstddef> |
| #include <memory> |
| #include <string> |
| |
| #include "common/config.h" |
| |
| #if PORTABLE_SAFT_MOBILE |
| #include <google/protobuf/io/zero_copy_stream_impl_lite.h> |
| #endif |
| |
| #include "common/mmap.h" |
| #include "util/strings/stringpiece.h" |
| |
| namespace libtextclassifier { |
| namespace nlp_core { |
| |
| namespace file_utils { |
| |
| // Reads the entire content of a file into a string. Returns true on success, |
| // false on error. |
| bool GetFileContent(const std::string &filename, std::string *content); |
| |
| // Parses a proto from its serialized representation in memory. That |
| // representation starts at address sp.data() and contains exactly sp.size() |
| // bytes. Returns true on success, false otherwise. |
| template<class Proto> |
| bool ParseProtoFromMemory(StringPiece sp, Proto *proto) { |
| if (!sp.data()) { |
| // Avoid passing a nullptr to ArrayInputStream below. |
| return false; |
| } |
| #if PORTABLE_SAFT_MOBILE |
| ::google::protobuf::io::ArrayInputStream stream(sp.data(), sp.size()); |
| return proto->ParseFromZeroCopyStream(&stream); |
| #else |
| |
| std::string data(sp.data(), sp.size()); |
| return proto->ParseFromString(data); |
| #endif |
| } |
| |
| // Parses a proto from a file. Returns true on success, false otherwise. |
| // |
| // Note: the entire content of the file should be the binary (not |
| // human-readable) serialization of a protocol buffer. |
| // |
| // Note: when we compile for Android, the proto parsing methods need to know the |
| // type of the message they are parsing. We use template polymorphism for that. |
| template<class Proto> |
| bool ReadProtoFromFile(const std::string &filename, Proto *proto) { |
| ScopedMmap scoped_mmap(filename); |
| const MmapHandle &handle = scoped_mmap.handle(); |
| if (!handle.ok()) { |
| return false; |
| } |
| return ParseProtoFromMemory(handle.to_stringpiece(), proto); |
| } |
| |
| // Returns true if filename is the name of an existing file, and false |
| // otherwise. |
| bool FileExists(const std::string &filename); |
| |
| // Returns true if dirpath is the path to an existing directory, and false |
| // otherwise. |
| bool DirectoryExists(const std::string &dirpath); |
| |
| } // namespace file_utils |
| |
| } // namespace nlp_core |
| } // namespace libtextclassifier |
| |
| #endif // LIBTEXTCLASSIFIER_COMMON_FILE_UTILS_H_ |