src/egl/main/egllog.c

   1 /**************************************************************************
   2  *
   3  * Copyright 2008 VMware, Inc.
   4  * Copyright 2009-2010 Chia-I Wu <olvaffe@gmail.com>
   5  * Copyright 2010 LunarG, Inc.
   6  * All Rights Reserved.
   7  *
   8  * Permission is hereby granted, free of charge, to any person obtaining a
   9  * copy of this software and associated documentation files (the
  10  * "Software"), to deal in the Software without restriction, including
  11  * without limitation the rights to use, copy, modify, merge, publish,
  12  * distribute, sub license, and/or sell copies of the Software, and to
  13  * permit persons to whom the Software is furnished to do so, subject to
  14  * the following conditions:
  15  *
  16  * The above copyright notice and this permission notice (including the
  17  * next paragraph) shall be included in all copies or substantial portions
  18  * of the Software.
  19  *
  20  * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
  21  * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
  22  * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.  IN NO EVENT SHALL
  23  * THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
  24  * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
  25  * FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER
  26  * DEALINGS IN THE SOFTWARE.
  27  *
  28  **************************************************************************/
  29
  30
  31 /**
  32  * Logging facility for debug/info messages.
  33  * _EGL_FATAL messages are printed to stderr
  34  * The EGL_LOG_LEVEL var controls the output of other warning/info/debug msgs.
  35  */
  36
  37
  38 #include <stdarg.h>
  39 #include <stdio.h>
  40 #include <stdlib.h>
  41 #include <string.h>
  42 #include <strings.h>
  43 #include "c11/threads.h"
  44
  45 #include "egllog.h"
  46
  47 #define MAXSTRING 1000
  48 #define FALLBACK_LOG_LEVEL _EGL_WARNING
  49
  50
  51 static struct {
  52    mtx_t mutex;
  53
  54    EGLBoolean initialized;
  55    EGLint level;
  56    _EGLLogProc logger;
  57    EGLint num_messages;
  58 } logging = {
  59    _MTX_INITIALIZER_NP,
  60    EGL_FALSE,
  61    FALLBACK_LOG_LEVEL,
  62    NULL,
  63    0
  64 };
  65
  66 static const char *level_strings[] = {
  67    /* the order is important */
  68    "fatal",
  69    "warning",
  70    "info",
  71    "debug",
  72    NULL
  73 };
  74
  75
  76 /**
  77  * Set the function to be called when there is a message to log.
  78  * Note that the function will be called with an internal lock held.
  79  * Recursive logging is not allowed.
  80  */
  81 void
  82 _eglSetLogProc(_EGLLogProc logger)
  83 {
  84    EGLint num_messages = 0;
  85
  86    mtx_lock(&logging.mutex);
  87
  88    if (logging.logger != logger) {
  89       logging.logger = logger;
  90
  91       num_messages = logging.num_messages;
  92       logging.num_messages = 0;
  93    }
  94
  95    mtx_unlock(&logging.mutex);
  96
  97    if (num_messages)
  98       _eglLog(_EGL_DEBUG,
  99               "New logger installed. "
 100               "Messages before the new logger might not be available.");
 101 }
 102
 103
 104 /**
 105  * The default logger.  It prints the message to stderr.
 106  */
 107 static void
 108 _eglDefaultLogger(EGLint level, const char *msg)
 109 {
 110    fprintf(stderr, "libEGL %s: %s\n", level_strings[level], msg);
 111 }
 112
 113
 114 /**
 115  * Initialize the logging facility.
 116  */
 117 static void
 118 _eglInitLogger(void)
 119 {
 120    const char *log_env;
 121    EGLint i, level = -1;
 122
 123    if (logging.initialized)
 124       return;
 125
 126    log_env = getenv("EGL_LOG_LEVEL");
 127    if (log_env) {
 128       for (i = 0; level_strings[i]; i++) {
 129          if (strcasecmp(log_env, level_strings[i]) == 0) {
 130             level = i;
 131             break;
 132          }
 133       }
 134    }
 135    else {
 136       level = FALLBACK_LOG_LEVEL;
 137    }
 138
 139    logging.logger = _eglDefaultLogger;
 140    logging.level = (level >= 0) ? level : FALLBACK_LOG_LEVEL;
 141    logging.initialized = EGL_TRUE;
 142
 143    /* it is fine to call _eglLog now */
 144    if (log_env && level < 0) {
 145       _eglLog(_EGL_WARNING,
 146               "Unrecognized EGL_LOG_LEVEL environment variable value. "
 147               "Expected one of \"fatal\", \"warning\", \"info\", \"debug\". "
 148               "Got \"%s\". Falling back to \"%s\".",
 149               log_env, level_strings[FALLBACK_LOG_LEVEL]);
 150    }
 151 }
 152
 153
 154 /**
 155  * Log a message with message logger.
 156  * \param level one of _EGL_FATAL, _EGL_WARNING, _EGL_INFO, _EGL_DEBUG.
 157  */
 158 void
 159 _eglLog(EGLint level, const char *fmtStr, ...)
 160 {
 161    va_list args;
 162    char msg[MAXSTRING];
 163    int ret;
 164
 165    /* one-time initialization; a little race here is fine */
 166    if (!logging.initialized)
 167       _eglInitLogger();
 168    if (level > logging.level || level < 0)
 169       return;
 170
 171    mtx_lock(&logging.mutex);
 172
 173    if (logging.logger) {
 174       va_start(args, fmtStr);
 175       ret = vsnprintf(msg, MAXSTRING, fmtStr, args);
 176       if (ret < 0 || ret >= MAXSTRING)
 177          strcpy(msg, "<message truncated>");
 178       va_end(args);
 179
 180       logging.logger(level, msg);
 181       logging.num_messages++;
 182    }
 183
 184    mtx_unlock(&logging.mutex);
 185
 186    if (level == _EGL_FATAL)
 187       exit(1); /* or abort()? */
 188 }