common/log.c

   1 /* -*- Mode: C ; c-basic-offset: 2 -*- */
   2 /*
   3  * LADI Session Handler (ladish)
   4  *
   5  * Copyright (C) 2008, 2009, 2010, 2012 Nedko Arnaudov <nedko@arnaudov.name>
   6  * Copyright (C) 2008 Marc-Olivier Barre
   7  *
   8  **************************************************************************
   9  * This file contains code that implements logging functionality
  10  **************************************************************************
  11  *
  12  * LADI Session Handler is free software; you can redistribute it and/or modify
  13  * it under the terms of the GNU General Public License as published by
  14  * the Free Software Foundation; either version 2 of the License, or
  15  * (at your option) any later version.
  16  *
  17  * LADI Session Handler is distributed in the hope that it will be useful,
  18  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  19  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  20  * GNU General Public License for more details.
  21  *
  22  * You should have received a copy of the GNU General Public License
  23  * along with LADI Session Handler. If not, see <http://www.gnu.org/licenses/>
  24  * or write to the Free Software Foundation, Inc.,
  25  * 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
  26  */
  27
  28 #include "config.h"
  29 #include "../common.h"
  30
  31 #include <errno.h>
  32 #include <time.h>
  33 #include <stdarg.h>
  34 #include <sys/stat.h>
  35
  36 #include "../common/catdup.h"
  37 #include "../common/dirhelpers.h"
  38
  39 #define DEFAULT_XDG_LOG "/.log"
  40 #define LADISH_XDG_SUBDIR "/" BASE_NAME
  41 #define LADISH_XDG_LOG "/" BASE_NAME ".log"
  42
  43 #if !defined(LOG_OUTPUT_STDOUT)
  44 static ino_t g_log_file_ino;
  45 static FILE * g_logfile;
  46 static char * g_log_filename;
  47
  48 static bool ladish_log_open(void)
  49 {
  50     struct stat st;
  51     int ret;
  52     int retry;
  53
  54     if (g_logfile != NULL)
  55     {
  56         ret = stat(g_log_filename, &st);
  57         if (ret != 0 || g_log_file_ino != st.st_ino)
  58         {
  59             fclose(g_logfile);
  60         }
  61         else
  62         {
  63             return true;
  64         }
  65     }
  66
  67     for (retry = 0; retry < 10; retry++)
  68     {
  69         g_logfile = fopen(g_log_filename, "a");
  70         if (g_logfile == NULL)
  71         {
  72             fprintf(stderr, "Cannot open ladishd log file \"%s\": %d (%s)\n", g_log_filename, errno, strerror(errno));
  73             return false;
  74         }
  75
  76         ret = stat(g_log_filename, &st);
  77         if (ret == 0)
  78         {
  79             g_log_file_ino = st.st_ino;
  80             return true;
  81         }
  82
  83         fclose(g_logfile);
  84         g_logfile = NULL;
  85     }
  86
  87     fprintf(stderr, "Cannot stat just opened ladishd log file \"%s\": %d (%s). %d retries\n", g_log_filename, errno, strerror(errno), retry);
  88     return false;
  89 }
  90
  91 void ladish_log_init() __attribute__ ((constructor));
  92 void ladish_log_init()
  93 {
  94   char * ladish_log_dir;
  95   const char * home_dir;
  96   char * xdg_log_home;
  97
  98   home_dir = getenv("HOME");
  99   if (home_dir == NULL)
 100   {
 101     log_error("Environment variable HOME not set");
 102     goto exit;
 103   }
 104
 105   xdg_log_home = catdup(home_dir, DEFAULT_XDG_LOG);
 106   if (xdg_log_home == NULL)
 107   {
 108     log_error("catdup failed for '%s' and '%s'", home_dir, DEFAULT_XDG_LOG);
 109     goto exit;
 110   }
 111
 112   ladish_log_dir = catdup(xdg_log_home, LADISH_XDG_SUBDIR);
 113   if (ladish_log_dir == NULL)
 114   {
 115     log_error("catdup failed for '%s' and '%s'", home_dir, LADISH_XDG_SUBDIR);
 116     goto free_log_home;
 117   }
 118
 119   if (!ensure_dir_exist(xdg_log_home, 0700))
 120   {
 121     goto free_log_dir;
 122   }
 123
 124   if (!ensure_dir_exist(ladish_log_dir, 0700))
 125   {
 126     goto free_log_dir;
 127   }
 128
 129   g_log_filename = catdup(ladish_log_dir, LADISH_XDG_LOG);
 130   if (g_log_filename == NULL)
 131   {
 132     log_error("Out of memory");
 133     goto free_log_dir;
 134   }
 135
 136   ladish_log_open();
 137   cdbus_log_setup(ladish_log);
 138
 139 free_log_dir:
 140   free(ladish_log_dir);
 141
 142 free_log_home:
 143   free(xdg_log_home);
 144
 145 exit:
 146   return;
 147 }
 148
 149 void ladish_log_uninit()  __attribute__ ((destructor));
 150 void ladish_log_uninit()
 151 {
 152   if (g_logfile != NULL)
 153   {
 154     fclose(g_logfile);
 155   }
 156
 157   free(g_log_filename);
 158 }
 159 #else
 160 void ladish_log_init() __attribute__ ((constructor));
 161 void ladish_log_init()
 162 {
 163   cdbus_log_setup(ladish_log);
 164 }
 165 #endif  /* #if !defined(LOG_OUTPUT_STDOUT) */
 166
 167 #if 0
 168 # define log_debug(fmt, args...) ladish_log(CDBUS_LOG_LEVEL_DEBUG, "%s:%d:%s: " fmt "\n", __FILE__, __LINE__, __func__, ## args)
 169 # define log_info(fmt, args...) ladish_log(CDBUS_LOG_LEVEL_INFO, fmt "\n", ## args)
 170 # define log_warn(fmt, args...) ladish_log(CDBUS_LOG_LEVEL_WARN, ANSI_COLOR_YELLOW "WARNING: " ANSI_RESET "%s: " fmt "\n", __func__, ## args)
 171 # define log_error(fmt, args...) ladish_log(CDBUS_LOG_LEVEL_ERROR, ANSI_COLOR_RED "ERROR: " ANSI_RESET "%s: " fmt "\n", __func__, ## args)
 172 # define log_error_plain(fmt, args...) ladish_log(CDBUS_LOG_LEVEL_ERROR_PLAIN, ANSI_COLOR_RED "ERROR: " ANSI_RESET fmt "\n", ## args)
 173 #endif
 174
 175 static
 176 bool
 177 ladish_log_enabled(
 178   unsigned int level,
 179   const char * UNUSED(file),
 180   unsigned int UNUSED(line),
 181   const char * UNUSED(func))
 182 {
 183   return level != CDBUS_LOG_LEVEL_DEBUG;
 184 }
 185
 186 void
 187 ladish_log(
 188   unsigned int level,
 189   const char * file,
 190   unsigned int line,
 191   const char * func,
 192   const char * format,
 193   ...)
 194 {
 195   va_list ap;
 196   FILE * stream;
 197 #if !defined(LOG_OUTPUT_STDOUT)
 198   time_t timestamp;
 199   char timestamp_str[26];
 200 #endif
 201   const char * color;
 202
 203   if (!ladish_log_enabled(level, file, line, func))
 204   {
 205     return;
 206   }
 207
 208 #if !defined(LOG_OUTPUT_STDOUT)
 209   if (g_logfile != NULL && ladish_log_open())
 210   {
 211     stream = g_logfile;
 212   }
 213   else
 214 #endif
 215   {
 216     switch (level)
 217     {
 218     case CDBUS_LOG_LEVEL_DEBUG:
 219     case CDBUS_LOG_LEVEL_INFO:
 220       stream = stdout;
 221       break;
 222     case CDBUS_LOG_LEVEL_WARN:
 223     case CDBUS_LOG_LEVEL_ERROR:
 224     case CDBUS_LOG_LEVEL_ERROR_PLAIN:
 225     default:
 226       stream = stderr;
 227     }
 228   }
 229
 230 #if !defined(LOG_OUTPUT_STDOUT)
 231   time(&timestamp);
 232   ctime_r(&timestamp, timestamp_str);
 233   timestamp_str[24] = 0;
 234
 235   fprintf(stream, "%s: ", timestamp_str);
 236 #endif
 237
 238   color = NULL;
 239   switch (level)
 240   {
 241   case CDBUS_LOG_LEVEL_DEBUG:
 242     fprintf(stream, "%s:%d:%s ", file, line, func);
 243     break;
 244   case CDBUS_LOG_LEVEL_WARN:
 245     color = ANSI_COLOR_YELLOW;
 246     break;
 247   case CDBUS_LOG_LEVEL_ERROR:
 248   case CDBUS_LOG_LEVEL_ERROR_PLAIN:
 249     color = ANSI_COLOR_RED;
 250     break;
 251   }
 252
 253   if (color != NULL)
 254   {
 255     fputs(color, stream);
 256   }
 257
 258   va_start(ap, format);
 259   vfprintf(stream, format, ap);
 260   va_end(ap);
 261
 262   if (color != NULL)
 263   {
 264     fputs(ANSI_RESET, stream);
 265   }
 266
 267   fputs("\n", stream);
 268
 269   fflush(stream);
 270 }