/* * 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. */ #define LOG_TAG "Tokenizer" #include <stdlib.h> #include <unistd.h> #include <fcntl.h> #include <errno.h> #include <sys/types.h> #include <sys/stat.h> #include <utils/Log.h> #include <utils/Tokenizer.h> // Enables debug output for the tokenizer. #define DEBUG_TOKENIZER 0 namespace android { static inline bool isDelimiter(char ch, const char* delimiters) { return strchr(delimiters, ch) != NULL; } Tokenizer::Tokenizer(const String8& filename, FileMap* fileMap, char* buffer, size_t length) : mFilename(filename), mFileMap(fileMap), mBuffer(buffer), mLength(length), mCurrent(buffer), mLineNumber(1) { } Tokenizer::~Tokenizer() { if (mFileMap) { mFileMap->release(); } else { delete[] mBuffer; } } status_t Tokenizer::open(const String8& filename, Tokenizer** outTokenizer) { *outTokenizer = NULL; int result = NO_ERROR; int fd = ::open(filename.string(), O_RDONLY); if (fd < 0) { result = -errno; ALOGE("Error opening file '%s', %s.", filename.string(), strerror(errno)); } else { struct stat stat; if (fstat(fd, &stat)) { result = -errno; ALOGE("Error getting size of file '%s', %s.", filename.string(), strerror(errno)); } else { size_t length = size_t(stat.st_size); FileMap* fileMap = new FileMap(); char* buffer; if (fileMap->create(NULL, fd, 0, length, true)) { fileMap->advise(FileMap::SEQUENTIAL); buffer = static_cast<char*>(fileMap->getDataPtr()); } else { fileMap->release(); fileMap = NULL; // Fall back to reading into a buffer since we can't mmap files in sysfs. // The length we obtained from stat is wrong too (it will always be 4096) // so we must trust that read will read the entire file. buffer = new char[length]; ssize_t nrd = read(fd, buffer, length); if (nrd < 0) { result = -errno; ALOGE("Error reading file '%s', %s.", filename.string(), strerror(errno)); delete[] buffer; buffer = NULL; } else { length = size_t(nrd); } } if (!result) { *outTokenizer = new Tokenizer(filename, fileMap, buffer, length); } } close(fd); } return result; } String8 Tokenizer::getLocation() const { String8 result; result.appendFormat("%s:%d", mFilename.string(), mLineNumber); return result; } String8 Tokenizer::peekRemainderOfLine() const { const char* end = getEnd(); const char* eol = mCurrent; while (eol != end) { char ch = *eol; if (ch == '\n') { break; } eol += 1; } return String8(mCurrent, eol - mCurrent); } String8 Tokenizer::nextToken(const char* delimiters) { #if DEBUG_TOKENIZER ALOGD("nextToken"); #endif const char* end = getEnd(); const char* tokenStart = mCurrent; while (mCurrent != end) { char ch = *mCurrent; if (ch == '\n' || isDelimiter(ch, delimiters)) { break; } mCurrent += 1; } return String8(tokenStart, mCurrent - tokenStart); } void Tokenizer::nextLine() { #if DEBUG_TOKENIZER ALOGD("nextLine"); #endif const char* end = getEnd(); while (mCurrent != end) { char ch = *(mCurrent++); if (ch == '\n') { mLineNumber += 1; break; } } } void Tokenizer::skipDelimiters(const char* delimiters) { #if DEBUG_TOKENIZER ALOGD("skipDelimiters"); #endif const char* end = getEnd(); while (mCurrent != end) { char ch = *mCurrent; if (ch == '\n' || !isDelimiter(ch, delimiters)) { break; } mCurrent += 1; } } } // namespace android