modules/logger/syslog.c

   1 /*****************************************************************************
   2  * syslog.c: POSIX syslog logger plugin
   3  *****************************************************************************
   4  * Copyright (C) 2002-2008 the VideoLAN team
   5  * Copyright © 2007-2015 Rémi Denis-Courmont
   6  *
   7  * This program is free software; you can redistribute it and/or modify
   8  * it under the terms of the GNU General Public License as published by
   9  * the Free Software Foundation; either version 2 of the License, or
  10  * (at your option) any later version.
  11  *
  12  * This program is distributed in the hope that it will be useful,
  13  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  14  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  15  * GNU General Public License for more details.
  16  *
  17  * You should have received a copy of the GNU General Public License along
  18  * with this program; if not, write to the Free Software Foundation, Inc.,
  19  * 51 Franklin Street, Fifth Floor, Boston MA 02110-1301, USA.
  20  *****************************************************************************/
  21
  22 #ifdef HAVE_CONFIG_H
  23 # include "config.h"
  24 #endif
  25
  26 #define VLC_MODULE_LICENSE VLC_LICENSE_GPL_2_PLUS
  27 #include <vlc_common.h>
  28 #include <vlc_plugin.h>
  29
  30 #include <stdarg.h>
  31 #include <syslog.h>
  32
  33 static const int priorities[4] = {
  34     [VLC_MSG_INFO] = LOG_INFO,
  35     [VLC_MSG_ERR]  = LOG_ERR,
  36     [VLC_MSG_WARN] = LOG_WARNING,
  37     [VLC_MSG_DBG]  = LOG_DEBUG,
  38 };
  39
  40 static void Log(void *opaque, int type, const vlc_log_t *meta,
  41                 const char *format, va_list ap)
  42 {
  43     static const char default_msg[] = "message lost";
  44     char *str;
  45     int priority = priorities[type];
  46
  47     if (vasprintf(&str, format, ap) == -1)
  48         str = (char *)default_msg;
  49
  50     if (meta->psz_header != NULL)
  51         syslog(priority, "[%s] %s: %s", meta->psz_header, meta->psz_module,
  52                str);
  53     else
  54         syslog(priority, "%s: %s", meta->psz_module, str);
  55
  56     if (str != default_msg)
  57         free(str);
  58     (void) opaque;
  59 }
  60
  61 /* First in list is the default facility used. */
  62 #define DEFINE_SYSLOG_FACILITY \
  63   DEF("user",   LOG_USER),   \
  64   DEF("daemon", LOG_DAEMON), \
  65   DEF("local0", LOG_LOCAL0), \
  66   DEF("local1", LOG_LOCAL1), \
  67   DEF("local2", LOG_LOCAL2), \
  68   DEF("local3", LOG_LOCAL3), \
  69   DEF("local4", LOG_LOCAL4), \
  70   DEF("local5", LOG_LOCAL5), \
  71   DEF("local6", LOG_LOCAL6), \
  72   DEF("local7", LOG_LOCAL7)
  73
  74 #define DEF(a,b) a
  75 static const char *const fac_names[] = { DEFINE_SYSLOG_FACILITY };
  76 #undef  DEF
  77 #define DEF(a,b) b
  78 static const int         fac_ids[] = { DEFINE_SYSLOG_FACILITY };
  79 #undef  DEF
  80 #undef  DEFINE_SYSLOG_FACILITY
  81
  82 static int var_InheritFacility(vlc_object_t *obj, const char *varname)
  83 {
  84     char *str = var_InheritString(obj, varname);
  85     if (unlikely(str == NULL))
  86         return LOG_USER; /* LOG_USEr is the spec default. */
  87
  88     for (size_t i = 0; i < sizeof (fac_ids) / sizeof (fac_ids[0]); i++)
  89     {
  90         if (!strcmp(str, fac_names[i]))
  91         {
  92             free(str);
  93             return fac_ids[i];
  94         }
  95     }
  96
  97     msg_Warn(obj, "unknown syslog facility \"%s\"", str);
  98     free(str);
  99     return LOG_USER;
 100 }
 101
 102 static const char default_ident[] = PACKAGE;
 103
 104 static vlc_log_cb Open(vlc_object_t *obj, void **sysp)
 105 {
 106     if (!var_InheritBool(obj, "syslog"))
 107         return NULL;
 108
 109     char *ident = var_InheritString(obj, "syslog-ident");
 110     if (ident == NULL)
 111         ident = (char *)default_ident;
 112     *sysp = ident;
 113
 114     /* Open log */
 115     int facility = var_InheritFacility(obj, "syslog-facility");
 116
 117     openlog(ident, LOG_PID | LOG_NDELAY, facility);
 118
 119     /* Set priority filter */
 120     int mask = LOG_MASK(LOG_ERR) | LOG_MASK(LOG_WARNING) | LOG_MASK(LOG_INFO);
 121     if (var_InheritBool(obj, "syslog-debug"))
 122         mask |= LOG_MASK(LOG_DEBUG);
 123
 124     setlogmask(mask);
 125
 126     return Log;
 127 }
 128
 129 static void Close(void *opaque)
 130 {
 131     char *ident = opaque;
 132
 133     closelog();
 134     if (ident != default_ident)
 135         free(ident);
 136 }
 137
 138 #define SYSLOG_TEXT N_("System log (syslog)")
 139 #define SYSLOG_LONGTEXT N_("Emit log messages through the POSIX system log.")
 140
 141 #define SYSLOG_DEBUG_TEXT N_("Debug messages")
 142 #define SYSLOG_DEBUG_LONGTEXT N_("Include debug messages in system log.")
 143
 144 #define SYSLOG_IDENT_TEXT N_("Identity")
 145 #define SYSLOG_IDENT_LONGTEXT N_("Process identity in system log.")
 146
 147 #define SYSLOG_FACILITY_TEXT N_("Facility")
 148 #define SYSLOG_FACILITY_LONGTEXT N_("System logging facility.")
 149
 150 vlc_module_begin()
 151     set_shortname(N_( "syslog" ))
 152     set_description(N_("System logger (syslog)"))
 153     set_category(CAT_ADVANCED)
 154     set_subcategory(SUBCAT_ADVANCED_MISC)
 155     set_capability("logger", 20)
 156     set_callbacks(Open, Close)
 157
 158     add_bool("syslog", false, SYSLOG_TEXT, SYSLOG_LONGTEXT,
 159              false)
 160     add_bool("syslog-debug", false, SYSLOG_DEBUG_TEXT, SYSLOG_DEBUG_LONGTEXT,
 161              false)
 162     add_string("syslog-ident", default_ident, SYSLOG_IDENT_TEXT,
 163                SYSLOG_IDENT_LONGTEXT, true)
 164     add_string("syslog-facility", fac_names[0], SYSLOG_FACILITY_TEXT,
 165                SYSLOG_FACILITY_LONGTEXT, true)
 166         change_string_list(fac_names, fac_names)
 167 vlc_module_end()