lib/logging.c

   1 /*
   2    Provides a log file to ease tracing the program.
   3
   4    Copyright (C) 2006, 2009, 2011
   5    The Free Software Foundation, Inc.
   6
   7    Written by:
   8    Roland Illig <roland.illig@gmx.de>, 2006
   9    Slava Zanko <slavazanko@gmail.com>, 2009, 2011
  10
  11    This file is part of the Midnight Commander.
  12
  13    The Midnight Commander is free software: you can redistribute it
  14    and/or modify it under the terms of the GNU General Public License as
  15    published by the Free Software Foundation, either version 3 of the License,
  16    or (at your option) any later version.
  17
  18    The Midnight Commander is distributed in the hope that it will be useful,
  19    but WITHOUT ANY WARRANTY; without even the implied warranty of
  20    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  21    GNU General Public License for more details.
  22
  23    You should have received a copy of the GNU General Public License
  24    along with this program.  If not, see <http://www.gnu.org/licenses/>.
  25  */
  26
  27 /** \file logging.c
  28  *  \brief Source: provides a log file to ease tracing the program
  29  */
  30
  31 #include <config.h>
  32
  33 #include <stdarg.h>
  34 #include <stdio.h>
  35
  36 #include "lib/global.h"
  37 #include "lib/mcconfig.h"
  38 #include "lib/fileloc.h"
  39
  40 #include "logging.h"
  41
  42 /*** global variables ****************************************************************************/
  43
  44 /*** file scope macro definitions ****************************************************************/
  45
  46 #define CONFIG_GROUP_NAME "Development"
  47 #define CONFIG_KEY_NAME "logging"
  48 #define CONFIG_KEY_NAME_FILE "logfile"
  49
  50 /*** file scope type declarations ****************************************************************/
  51
  52 /*** file scope variables ************************************************************************/
  53
  54 static gboolean logging_initialized = FALSE;
  55 static gboolean logging_enabled = FALSE;
  56
  57 /*** file scope functions ************************************************************************/
  58 /* --------------------------------------------------------------------------------------------- */
  59
  60 static gboolean
  61 is_logging_enabled_from_env (void)
  62 {
  63     const char *env_is_enabled;
  64
  65     env_is_enabled = g_getenv ("MC_LOG_ENABLE");
  66     if (env_is_enabled == NULL)
  67         return FALSE;
  68
  69     logging_enabled = (*env_is_enabled == '1' || g_ascii_strcasecmp (env_is_enabled, "true") == 0);
  70     logging_initialized = TRUE;
  71     return TRUE;
  72 }
  73
  74 /* --------------------------------------------------------------------------------------------- */
  75
  76 static gboolean
  77 is_logging_enabled (void)
  78 {
  79
  80     if (logging_initialized)
  81         return logging_enabled;
  82
  83     if (is_logging_enabled_from_env ())
  84         return logging_enabled;
  85
  86     logging_enabled =
  87         mc_config_get_bool (mc_main_config, CONFIG_GROUP_NAME, CONFIG_KEY_NAME, FALSE);
  88     logging_initialized = TRUE;
  89
  90     return logging_enabled;
  91 }
  92
  93 /* --------------------------------------------------------------------------------------------- */
  94
  95 static char *
  96 get_log_filename (void)
  97 {
  98     const char *env_filename;
  99
 100     env_filename = g_getenv ("MC_LOG_FILE");
 101     if (env_filename != NULL)
 102         return g_strdup (env_filename);
 103
 104     if (mc_config_has_param (mc_main_config, CONFIG_GROUP_NAME, CONFIG_KEY_NAME_FILE))
 105         return mc_config_get_string (mc_main_config, CONFIG_GROUP_NAME, CONFIG_KEY_NAME_FILE, NULL);
 106
 107     return mc_config_get_full_path ("mc.log");
 108 }
 109
 110 /* --------------------------------------------------------------------------------------------- */
 111
 112 static void
 113 mc_va_log (const char *fmt, va_list args)
 114 {
 115     FILE *f;
 116     char *logfilename;
 117
 118     logfilename = get_log_filename ();
 119
 120     if (logfilename != NULL)
 121     {
 122         f = fopen (logfilename, "a");
 123         if (f != NULL)
 124         {
 125             (void) vfprintf (f, fmt, args);
 126             (void) fclose (f);
 127         }
 128         g_free (logfilename);
 129     }
 130
 131 }
 132
 133 /* --------------------------------------------------------------------------------------------- */
 134 /*** public functions ****************************************************************************/
 135 /* --------------------------------------------------------------------------------------------- */
 136
 137 void
 138 mc_log (const char *fmt, ...)
 139 {
 140     va_list args;
 141
 142     if (!is_logging_enabled ())
 143         return;
 144
 145     va_start (args, fmt);
 146     mc_va_log (fmt, args);
 147     va_end (args);
 148 }
 149
 150 /* --------------------------------------------------------------------------------------------- */
 151
 152 void
 153 mc_always_log (const char *fmt, ...)
 154 {
 155     va_list args;
 156
 157     va_start (args, fmt);
 158     mc_va_log (fmt, args);
 159     va_end (args);
 160 }
 161
 162 /* --------------------------------------------------------------------------------------------- */