/* * Copyright (C) 2010 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 _UTILS_TOKENIZER_H #define _UTILS_TOKENIZER_H #include <assert.h> #include <utils/Errors.h> #include <utils/FileMap.h> #include <utils/String8.h> namespace android { /** * A simple tokenizer for loading and parsing ASCII text files line by line. */ class Tokenizer { Tokenizer(const String8& filename, FileMap* fileMap, char* buffer, bool ownBuffer, size_t length); public: ~Tokenizer(); /** * Opens a file and maps it into memory. * * Returns OK and a tokenizer for the file, if successful. * Otherwise returns an error and sets outTokenizer to NULL. */ static status_t open(const String8& filename, Tokenizer** outTokenizer); /** * Prepares to tokenize the contents of a string. * * Returns OK and a tokenizer for the string, if successful. * Otherwise returns an error and sets outTokenizer to NULL. */ static status_t fromContents(const String8& filename, const char* contents, Tokenizer** outTokenizer); /** * Returns true if at the end of the file. */ inline bool isEof() const { return mCurrent == getEnd(); } /** * Returns true if at the end of the line or end of the file. */ inline bool isEol() const { return isEof() || *mCurrent == '\n'; } /** * Gets the name of the file. */ inline String8 getFilename() const { return mFilename; } /** * Gets a 1-based line number index for the current position. */ inline int32_t getLineNumber() const { return mLineNumber; } /** * Formats a location string consisting of the filename and current line number. * Returns a string like "MyFile.txt:33". */ String8 getLocation() const; /** * Gets the character at the current position. * Returns null at end of file. */ inline char peekChar() const { return isEof() ? '\0' : *mCurrent; } /** * Gets the remainder of the current line as a string, excluding the newline character. */ String8 peekRemainderOfLine() const; /** * Gets the character at the current position and advances past it. * Returns null at end of file. */ inline char nextChar() { return isEof() ? '\0' : *(mCurrent++); } /** * Gets the next token on this line stopping at the specified delimiters * or the end of the line whichever comes first and advances past it. * Also stops at embedded nulls. * Returns the token or an empty string if the current character is a delimiter * or is at the end of the line. */ String8 nextToken(const char* delimiters); /** * Advances to the next line. * Does nothing if already at the end of the file. */ void nextLine(); /** * Skips over the specified delimiters in the line. * Also skips embedded nulls. */ void skipDelimiters(const char* delimiters); private: Tokenizer(const Tokenizer& other); // not copyable String8 mFilename; FileMap* mFileMap; char* mBuffer; bool mOwnBuffer; size_t mLength; const char* mCurrent; int32_t mLineNumber; inline const char* getEnd() const { return mBuffer + mLength; } }; } // namespace android #endif // _UTILS_TOKENIZER_H