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 #include "allocation.h" 32 33 namespace v8 { 34 namespace internal { 35 36 class Logger; 37 38 // Functions and data for performing output of log messages. 39 class Log { 40 public: 41 // Performs process-wide initialization. 42 void Initialize(const char* log_file_name); 43 44 // Disables logging, but preserves acquired resources. stop()45 void stop() { is_stopped_ = true; } 46 InitLogAtStart()47 static bool InitLogAtStart() { 48 return FLAG_log || FLAG_log_runtime || FLAG_log_api 49 || FLAG_log_code || FLAG_log_gc || FLAG_log_handles || FLAG_log_suspect 50 || FLAG_log_regexp || FLAG_ll_prof || FLAG_perf_basic_prof 51 || FLAG_perf_jit_prof || FLAG_log_internal_timer_events; 52 } 53 54 // Frees all resources acquired in Initialize and Open... functions. 55 // When a temporary file is used for the log, returns its stream descriptor, 56 // leaving the file open. 57 FILE* Close(); 58 59 // Returns whether logging is enabled. IsEnabled()60 bool IsEnabled() { 61 return !is_stopped_ && output_handle_ != NULL; 62 } 63 64 // Size of buffer used for formatting log messages. 65 static const int kMessageBufferSize = 2048; 66 67 // This mode is only used in tests, as temporary files are automatically 68 // deleted on close and thus can't be accessed afterwards. 69 static const char* const kLogToTemporaryFile; 70 static const char* const kLogToConsole; 71 72 // Utility class for formatting log messages. It fills the message into the 73 // static buffer in Log. 74 class MessageBuilder BASE_EMBEDDED { 75 public: 76 // Create a message builder starting from position 0. 77 // This acquires the mutex in the log as well. 78 explicit MessageBuilder(Log* log); ~MessageBuilder()79 ~MessageBuilder() { } 80 81 // Append string data to the log message. 82 void Append(const char* format, ...); 83 84 // Append string data to the log message. 85 void AppendVA(const char* format, va_list args); 86 87 // Append a character to the log message. 88 void Append(const char c); 89 90 // Append double quoted string to the log message. 91 void AppendDoubleQuotedString(const char* string); 92 93 // Append a heap string. 94 void Append(String* str); 95 96 // Appends an address. 97 void AppendAddress(Address addr); 98 99 void AppendSymbolName(Symbol* symbol); 100 101 void AppendDetailed(String* str, bool show_impl_info); 102 103 // Append a portion of a string. 104 void AppendStringPart(const char* str, int len); 105 106 // Write the log message to the log file currently opened. 107 void WriteToLogFile(); 108 109 private: 110 Log* log_; 111 LockGuard<Mutex> lock_guard_; 112 int pos_; 113 }; 114 115 private: 116 explicit Log(Logger* logger); 117 118 // Opens stdout for logging. 119 void OpenStdout(); 120 121 // Opens file for logging. 122 void OpenFile(const char* name); 123 124 // Opens a temporary file for logging. 125 void OpenTemporaryFile(); 126 127 // Implementation of writing to a log file. WriteToFile(const char * msg,int length)128 int WriteToFile(const char* msg, int length) { 129 ASSERT(output_handle_ != NULL); 130 size_t rv = fwrite(msg, 1, length, output_handle_); 131 ASSERT(static_cast<size_t>(length) == rv); 132 USE(rv); 133 fflush(output_handle_); 134 return length; 135 } 136 137 // Whether logging is stopped (e.g. due to insufficient resources). 138 bool is_stopped_; 139 140 // When logging is active output_handle_ is used to store a pointer to log 141 // destination. mutex_ should be acquired before using output_handle_. 142 FILE* output_handle_; 143 144 // mutex_ is a Mutex used for enforcing exclusive 145 // access to the formatting buffer and the log file or log memory buffer. 146 Mutex mutex_; 147 148 // Buffer used for formatting log messages. This is a singleton buffer and 149 // mutex_ should be acquired before using it. 150 char* message_buffer_; 151 152 Logger* logger_; 153 154 friend class Logger; 155 }; 156 157 158 } } // namespace v8::internal 159 160 #endif // V8_LOG_UTILS_H_ 161