1 /* 2 * Copyright (C) 2010 The Android Open Source Project 3 * 4 * Licensed under the Apache License, Version 2.0 (the "License"); 5 * you may not use this file except in compliance with the License. 6 * You may obtain a copy of the License at 7 * 8 * http://www.apache.org/licenses/LICENSE-2.0 9 * 10 * Unless required by applicable law or agreed to in writing, software 11 * distributed under the License is distributed on an "AS IS" BASIS, 12 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. 13 * See the License for the specific language governing permissions and 14 * limitations under the License. 15 */ 16 17 #define LOG_TAG "Tokenizer" 18 19 #include <utils/Tokenizer.h> 20 #include <fcntl.h> 21 #include <sys/stat.h> 22 #include <utils/Log.h> 23 24 // Enables debug output for the tokenizer. 25 #define DEBUG_TOKENIZER 0 26 27 28 namespace android { 29 30 static inline bool isDelimiter(char ch, const char* delimiters) { 31 return strchr(delimiters, ch) != NULL; 32 } 33 34 Tokenizer::Tokenizer(const String8& filename, FileMap* fileMap, char* buffer, 35 bool ownBuffer, size_t length) : 36 mFilename(filename), mFileMap(fileMap), 37 mBuffer(buffer), mOwnBuffer(ownBuffer), mLength(length), 38 mCurrent(buffer), mLineNumber(1) { 39 } 40 41 Tokenizer::~Tokenizer() { 42 delete mFileMap; 43 if (mOwnBuffer) { 44 delete[] mBuffer; 45 } 46 } 47 48 status_t Tokenizer::open(const String8& filename, Tokenizer** outTokenizer) { 49 *outTokenizer = NULL; 50 51 int result = NO_ERROR; 52 int fd = ::open(filename.string(), O_RDONLY); 53 if (fd < 0) { 54 result = -errno; 55 ALOGE("Error opening file '%s': %s", filename.string(), strerror(errno)); 56 } else { 57 struct stat stat; 58 if (fstat(fd, &stat)) { 59 result = -errno; 60 ALOGE("Error getting size of file '%s': %s", filename.string(), strerror(errno)); 61 } else { 62 size_t length = size_t(stat.st_size); 63 64 FileMap* fileMap = new FileMap(); 65 bool ownBuffer = false; 66 char* buffer; 67 if (fileMap->create(NULL, fd, 0, length, true)) { 68 fileMap->advise(FileMap::SEQUENTIAL); 69 buffer = static_cast<char*>(fileMap->getDataPtr()); 70 } else { 71 delete fileMap; 72 fileMap = NULL; 73 74 // Fall back to reading into a buffer since we can't mmap files in sysfs. 75 // The length we obtained from stat is wrong too (it will always be 4096) 76 // so we must trust that read will read the entire file. 77 buffer = new char[length]; 78 ownBuffer = true; 79 ssize_t nrd = read(fd, buffer, length); 80 if (nrd < 0) { 81 result = -errno; 82 ALOGE("Error reading file '%s': %s", filename.string(), strerror(errno)); 83 delete[] buffer; 84 buffer = NULL; 85 } else { 86 length = size_t(nrd); 87 } 88 } 89 90 if (!result) { 91 *outTokenizer = new Tokenizer(filename, fileMap, buffer, ownBuffer, length); 92 } 93 } 94 close(fd); 95 } 96 return result; 97 } 98 99 status_t Tokenizer::fromContents(const String8& filename, 100 const char* contents, Tokenizer** outTokenizer) { 101 *outTokenizer = new Tokenizer(filename, NULL, 102 const_cast<char*>(contents), false, strlen(contents)); 103 return OK; 104 } 105 106 String8 Tokenizer::getLocation() const { 107 String8 result; 108 result.appendFormat("%s:%d", mFilename.string(), mLineNumber); 109 return result; 110 } 111 112 String8 Tokenizer::peekRemainderOfLine() const { 113 const char* end = getEnd(); 114 const char* eol = mCurrent; 115 while (eol != end) { 116 char ch = *eol; 117 if (ch == '\n') { 118 break; 119 } 120 eol += 1; 121 } 122 return String8(mCurrent, eol - mCurrent); 123 } 124 125 String8 Tokenizer::nextToken(const char* delimiters) { 126 #if DEBUG_TOKENIZER 127 ALOGD("nextToken"); 128 #endif 129 const char* end = getEnd(); 130 const char* tokenStart = mCurrent; 131 while (mCurrent != end) { 132 char ch = *mCurrent; 133 if (ch == '\n' || isDelimiter(ch, delimiters)) { 134 break; 135 } 136 mCurrent += 1; 137 } 138 return String8(tokenStart, mCurrent - tokenStart); 139 } 140 141 void Tokenizer::nextLine() { 142 #if DEBUG_TOKENIZER 143 ALOGD("nextLine"); 144 #endif 145 const char* end = getEnd(); 146 while (mCurrent != end) { 147 char ch = *(mCurrent++); 148 if (ch == '\n') { 149 mLineNumber += 1; 150 break; 151 } 152 } 153 } 154 155 void Tokenizer::skipDelimiters(const char* delimiters) { 156 #if DEBUG_TOKENIZER 157 ALOGD("skipDelimiters"); 158 #endif 159 const char* end = getEnd(); 160 while (mCurrent != end) { 161 char ch = *mCurrent; 162 if (ch == '\n' || !isDelimiter(ch, delimiters)) { 163 break; 164 } 165 mCurrent += 1; 166 } 167 } 168 169 } // namespace android 170
