lib/logging.c

   1 /*
   2    Provides a log file to ease tracing the program.
   3
   4    Copyright (C) 2006, 2009 Free Software Foundation, Inc.
   5
   6    Written: 2006 Roland Illig <roland.illig@gmx.de>.
   7
   8    This file is part of the Midnight Commander.
   9
  10    The Midnight Commander is free software; you can redistribute it
  11    and/or modify it under the terms of the GNU General Public License as
  12    published by the Free Software Foundation; either version 2 of the
  13    License, or (at your option) any later version.
  14
  15    The Midnight Commander is distributed in the hope that it will be
  16    useful, but WITHOUT ANY WARRANTY; without even the implied warranty
  17    of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  18    General Public License for more details.
  19
  20    You should have received a copy of the GNU General Public License
  21    along with this program; if not, write to the Free Software
  22    Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston,
  23    MA 02110-1301, USA.
  24  */
  25
  26 /** \file logging.c
  27  *  \brief Source: provides a log file to ease tracing the program
  28  */
  29
  30 #include <config.h>
  31
  32 #include <stdarg.h>
  33 #include <stdio.h>
  34
  35 #include "lib/global.h"
  36 #include "lib/mcconfig.h"
  37 #include "lib/fileloc.h"
  38
  39 #include "logging.h"
  40
  41 /*** global variables ****************************************************************************/
  42
  43 /*** file scope macro definitions ****************************************************************/
  44
  45 #define CONFIG_GROUP_NAME "Development"
  46 #define CONFIG_KEY_NAME "logging"
  47 #define CONFIG_KEY_NAME_FILE "logfile"
  48
  49 /*** file scope type declarations ****************************************************************/
  50
  51 /*** file scope variables ************************************************************************/
  52
  53 static gboolean logging_initialized = FALSE;
  54 static gboolean logging_enabled = FALSE;
  55
  56 /*** file scope functions ************************************************************************/
  57 /* --------------------------------------------------------------------------------------------- */
  58
  59 static gboolean
  60 is_logging_enabled_from_env (void)
  61 {
  62     const char *env_is_enabled;
  63
  64     env_is_enabled = g_getenv ("MC_LOG_ENABLE");
  65     if (env_is_enabled == NULL)
  66         return FALSE;
  67
  68     logging_enabled = (*env_is_enabled == '1' || g_ascii_strcasecmp (env_is_enabled, "true") == 0);
  69     logging_initialized = TRUE;
  70     return TRUE;
  71 }
  72
  73 /* --------------------------------------------------------------------------------------------- */
  74
  75 static gboolean
  76 is_logging_enabled (void)
  77 {
  78
  79     if (logging_initialized)
  80         return logging_enabled;
  81
  82     if (is_logging_enabled_from_env ())
  83         return logging_enabled;
  84
  85     logging_enabled =
  86         mc_config_get_bool (mc_main_config, CONFIG_GROUP_NAME, CONFIG_KEY_NAME, FALSE);
  87     logging_initialized = TRUE;
  88
  89     return logging_enabled;
  90 }
  91
  92 /* --------------------------------------------------------------------------------------------- */
  93
  94 static char *
  95 get_log_filename (void)
  96 {
  97     const char *env_filename;
  98
  99     env_filename = g_getenv ("MC_LOG_FILE");
 100     if (env_filename != NULL)
 101         return g_strdup (env_filename);
 102
 103     if (mc_config_has_param (mc_main_config, CONFIG_GROUP_NAME, CONFIG_KEY_NAME_FILE))
 104         return mc_config_get_string (mc_main_config, CONFIG_GROUP_NAME, CONFIG_KEY_NAME_FILE, NULL);
 105
 106     return g_build_filename (mc_config_get_cache_path (), "mc.log", NULL);
 107 }
 108
 109 /* --------------------------------------------------------------------------------------------- */
 110
 111 static void
 112 mc_va_log (const char *fmt, va_list args)
 113 {
 114     FILE *f;
 115     char *logfilename;
 116
 117     logfilename = get_log_filename ();
 118
 119     if (logfilename != NULL)
 120     {
 121         f = fopen (logfilename, "a");
 122         if (f != NULL)
 123         {
 124             (void) vfprintf (f, fmt, args);
 125             (void) fclose (f);
 126         }
 127         g_free (logfilename);
 128     }
 129
 130 }
 131
 132 /* --------------------------------------------------------------------------------------------- */
 133 /*** public functions ****************************************************************************/
 134 /* --------------------------------------------------------------------------------------------- */
 135
 136 void
 137 mc_log (const char *fmt, ...)
 138 {
 139     va_list args;
 140
 141     if (!is_logging_enabled ())
 142         return;
 143
 144     va_start (args, fmt);
 145     mc_va_log (fmt, args);
 146     va_end (args);
 147 }
 148
 149 /* --------------------------------------------------------------------------------------------- */
 150
 151 void
 152 mc_always_log (const char *fmt, ...)
 153 {
 154     va_list args;
 155
 156     va_start (args, fmt);
 157     mc_va_log (fmt, args);
 158     va_end (args);
 159 }
 160
 161 /* --------------------------------------------------------------------------------------------- */