1 // Copyright 2006-2009 the V8 project authors. All rights reserved. 2 // Redistribution and use in source and binary forms, with or without 3 // modification, are permitted provided that the following conditions are 4 // met: 5 // 6 // * Redistributions of source code must retain the above copyright 7 // notice, this list of conditions and the following disclaimer. 8 // * Redistributions in binary form must reproduce the above 9 // copyright notice, this list of conditions and the following 10 // disclaimer in the documentation and/or other materials provided 11 // with the distribution. 12 // * Neither the name of Google Inc. nor the names of its 13 // contributors may be used to endorse or promote products derived 14 // from this software without specific prior written permission. 15 // 16 // THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS 17 // "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT 18 // LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR 19 // A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT 20 // OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, 21 // SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT 22 // LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, 23 // DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY 24 // THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT 25 // (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE 26 // OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. 27 28 #ifndef V8_LOG_UTILS_H_ 29 #define V8_LOG_UTILS_H_ 30 31 namespace v8 { 32 namespace internal { 33 34 #ifdef ENABLE_LOGGING_AND_PROFILING 35 36 class Logger; 37 38 // A memory buffer that increments its size as you write in it. Size 39 // is incremented with 'block_size' steps, never exceeding 'max_size'. 40 // During growth, memory contents are never copied. At the end of the 41 // buffer an amount of memory specified in 'seal_size' is reserved. 42 // When writing position reaches max_size - seal_size, buffer auto-seals 43 // itself with 'seal' and allows no further writes. Data pointed by 44 // 'seal' must be available during entire LogDynamicBuffer lifetime. 45 // 46 // An instance of this class is created dynamically by Log. 47 class LogDynamicBuffer { 48 public: 49 LogDynamicBuffer( 50 int block_size, int max_size, const char* seal, int seal_size); 51 52 ~LogDynamicBuffer(); 53 54 // Reads contents of the buffer starting from 'from_pos'. Upon 55 // return, 'dest_buf' is filled with the data. Actual amount of data 56 // filled is returned, it is <= 'buf_size'. 57 int Read(int from_pos, char* dest_buf, int buf_size); 58 59 // Writes 'data' to the buffer, making it larger if necessary. If 60 // data is too big to fit in the buffer, it doesn't get written at 61 // all. In that case, buffer auto-seals itself and stops to accept 62 // any incoming writes. Returns amount of data written (it is either 63 // 'data_size', or 0, if 'data' is too big). 64 int Write(const char* data, int data_size); 65 66 private: 67 void AllocateBlock(int index) { 68 blocks_[index] = NewArray<char>(block_size_); 69 } 70 71 int BlockIndex(int pos) const { return pos / block_size_; } 72 73 int BlocksCount() const { return BlockIndex(max_size_) + 1; } 74 75 int PosInBlock(int pos) const { return pos % block_size_; } 76 77 int Seal(); 78 79 int WriteInternal(const char* data, int data_size); 80 81 const int block_size_; 82 const int max_size_; 83 const char* seal_; 84 const int seal_size_; 85 ScopedVector<char*> blocks_; 86 int write_pos_; 87 int block_index_; 88 int block_write_pos_; 89 bool is_sealed_; 90 }; 91 92 93 // Functions and data for performing output of log messages. 94 class Log { 95 public: 96 97 // Performs process-wide initialization. 98 void Initialize(); 99 100 // Disables logging, but preserves acquired resources. 101 void stop() { is_stopped_ = true; } 102 103 // Frees all resources acquired in Initialize and Open... functions. 104 void Close(); 105 106 // See description in include/v8.h. 107 int GetLogLines(int from_pos, char* dest_buf, int max_size); 108 109 // Returns whether logging is enabled. 110 bool IsEnabled() { 111 return !is_stopped_ && (output_handle_ != NULL || output_buffer_ != NULL); 112 } 113 114 // Size of buffer used for formatting log messages. 115 static const int kMessageBufferSize = v8::V8::kMinimumSizeForLogLinesBuffer; 116 117 private: 118 explicit Log(Logger* logger); 119 120 // Opens stdout for logging. 121 void OpenStdout(); 122 123 // Opens file for logging. 124 void OpenFile(const char* name); 125 126 // Opens memory buffer for logging. 127 void OpenMemoryBuffer(); 128 129 // Implementation of writing to a log file. 130 int WriteToFile(const char* msg, int length) { 131 ASSERT(output_handle_ != NULL); 132 size_t rv = fwrite(msg, 1, length, output_handle_); 133 ASSERT(static_cast<size_t>(length) == rv); 134 USE(rv); 135 fflush(output_handle_); 136 return length; 137 } 138 139 // Implementation of writing to a memory buffer. 140 int WriteToMemory(const char* msg, int length) { 141 ASSERT(output_buffer_ != NULL); 142 return output_buffer_->Write(msg, length); 143 } 144 145 bool write_to_file_; 146 147 // Whether logging is stopped (e.g. due to insufficient resources). 148 bool is_stopped_; 149 150 // When logging is active, either output_handle_ or output_buffer_ is used 151 // to store a pointer to log destination. If logging was opened via OpenStdout 152 // or OpenFile, then output_handle_ is used. If logging was opened 153 // via OpenMemoryBuffer, then output_buffer_ is used. 154 // mutex_ should be acquired before using output_handle_ or output_buffer_. 155 FILE* output_handle_; 156 157 // Used when low-level profiling is active to save code object contents. 158 FILE* output_code_handle_; 159 160 LogDynamicBuffer* output_buffer_; 161 162 // Size of dynamic buffer block (and dynamic buffer initial size). 163 static const int kDynamicBufferBlockSize = 65536; 164 165 // Maximum size of dynamic buffer. 166 static const int kMaxDynamicBufferSize = 50 * 1024 * 1024; 167 168 // Message to "seal" dynamic buffer with. 169 static const char* const kDynamicBufferSeal; 170 171 // mutex_ is a Mutex used for enforcing exclusive 172 // access to the formatting buffer and the log file or log memory buffer. 173 Mutex* mutex_; 174 175 // Buffer used for formatting log messages. This is a singleton buffer and 176 // mutex_ should be acquired before using it. 177 char* message_buffer_; 178 179 Logger* logger_; 180 181 friend class Logger; 182 friend class LogMessageBuilder; 183 }; 184 185 186 // Utility class for formatting log messages. It fills the message into the 187 // static buffer in Log. 188 class LogMessageBuilder BASE_EMBEDDED { 189 public: 190 // Create a message builder starting from position 0. This acquires the mutex 191 // in the log as well. 192 explicit LogMessageBuilder(Logger* logger); 193 ~LogMessageBuilder() { } 194 195 // Append string data to the log message. 196 void Append(const char* format, ...); 197 198 // Append string data to the log message. 199 void AppendVA(const char* format, va_list args); 200 201 // Append a character to the log message. 202 void Append(const char c); 203 204 // Append a heap string. 205 void Append(String* str); 206 207 // Appends an address. 208 void AppendAddress(Address addr); 209 210 void AppendDetailed(String* str, bool show_impl_info); 211 212 // Append a portion of a string. 213 void AppendStringPart(const char* str, int len); 214 215 // Write the log message to the log file currently opened. 216 void WriteToLogFile(); 217 218 private: 219 220 Log* log_; 221 ScopedLock sl; 222 int pos_; 223 }; 224 225 #endif // ENABLE_LOGGING_AND_PROFILING 226 227 } } // namespace v8::internal 228 229 #endif // V8_LOG_UTILS_H_ 230
