1 // Copyright 2006-2009 the V8 project authors. All rights reserved.
2 // Use of this source code is governed by a BSD-style license that can be
3 // found in the LICENSE file.
5 #ifndef V8_LOG_UTILS_H_
6 #define V8_LOG_UTILS_H_
8 #include "src/allocation.h"
15 // Functions and data for performing output of log messages.
18 // Performs process-wide initialization.
19 void Initialize(const char* log_file_name);
21 // Disables logging, but preserves acquired resources.
22 void stop() { is_stopped_ = true; }
24 static bool InitLogAtStart() {
25 return FLAG_log || FLAG_log_api || FLAG_log_code || FLAG_log_gc
26 || FLAG_log_handles || FLAG_log_suspect || FLAG_log_regexp
27 || FLAG_ll_prof || FLAG_perf_basic_prof || FLAG_perf_jit_prof
28 || FLAG_log_internal_timer_events;
31 // Frees all resources acquired in Initialize and Open... functions.
32 // When a temporary file is used for the log, returns its stream descriptor,
33 // leaving the file open.
36 // Returns whether logging is enabled.
38 return !is_stopped_ && output_handle_ != NULL;
41 // Size of buffer used for formatting log messages.
42 static const int kMessageBufferSize = 2048;
44 // This mode is only used in tests, as temporary files are automatically
45 // deleted on close and thus can't be accessed afterwards.
46 static const char* const kLogToTemporaryFile;
47 static const char* const kLogToConsole;
49 // Utility class for formatting log messages. It fills the message into the
50 // static buffer in Log.
51 class MessageBuilder BASE_EMBEDDED {
53 // Create a message builder starting from position 0.
54 // This acquires the mutex in the log as well.
55 explicit MessageBuilder(Log* log);
58 // Append string data to the log message.
59 void Append(const char* format, ...);
61 // Append string data to the log message.
62 void AppendVA(const char* format, va_list args);
64 // Append a character to the log message.
65 void Append(const char c);
67 // Append double quoted string to the log message.
68 void AppendDoubleQuotedString(const char* string);
70 // Append a heap string.
71 void Append(String* str);
73 // Appends an address.
74 void AppendAddress(Address addr);
76 void AppendSymbolName(Symbol* symbol);
78 void AppendDetailed(String* str, bool show_impl_info);
80 // Append a portion of a string.
81 void AppendStringPart(const char* str, int len);
83 // Write the log message to the log file currently opened.
84 void WriteToLogFile();
88 LockGuard<Mutex> lock_guard_;
93 explicit Log(Logger* logger);
95 // Opens stdout for logging.
98 // Opens file for logging.
99 void OpenFile(const char* name);
101 // Opens a temporary file for logging.
102 void OpenTemporaryFile();
104 // Implementation of writing to a log file.
105 int WriteToFile(const char* msg, int length) {
106 ASSERT(output_handle_ != NULL);
107 size_t rv = fwrite(msg, 1, length, output_handle_);
108 ASSERT(static_cast<size_t>(length) == rv);
110 fflush(output_handle_);
114 // Whether logging is stopped (e.g. due to insufficient resources).
117 // When logging is active output_handle_ is used to store a pointer to log
118 // destination. mutex_ should be acquired before using output_handle_.
119 FILE* output_handle_;
121 // mutex_ is a Mutex used for enforcing exclusive
122 // access to the formatting buffer and the log file or log memory buffer.
125 // Buffer used for formatting log messages. This is a singleton buffer and
126 // mutex_ should be acquired before using it.
127 char* message_buffer_;
135 } } // namespace v8::internal
137 #endif // V8_LOG_UTILS_H_