logger.c

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/*
 * Asterisk -- An open source telephony toolkit.
 *
 * Copyright (C) 1999 - 2006, Digium, Inc.
 *
 * Mark Spencer <markster@digium.com>
 *
 * See http://www.asterisk.org for more information about
 * the Asterisk project. Please do not directly contact
 * any of the maintainers of this project for assistance;
 * the project provides a web site, mailing lists and IRC
 * channels for your use.
 *
 * This program is free software, distributed under the terms of
 * the GNU General Public License Version 2. See the LICENSE file
 * at the top of the source tree.
 */

/*! \file
 *
 * \brief Asterisk Logger
 *
 * Logging routines
 *
 * \author Mark Spencer <markster@digium.com>
 */

#include "asterisk.h"

ASTERISK_FILE_VERSION(__FILE__, "$Revision: 360933 $")

/* When we include logger.h again it will trample on some stuff in syslog.h, but
 * nothing we care about in here. */
#include <syslog.h>

#include "asterisk/_private.h"
#include "asterisk/paths.h"   /* use ast_config_AST_LOG_DIR */
#include "asterisk/logger.h"
#include "asterisk/lock.h"
#include "asterisk/channel.h"
#include "asterisk/config.h"
#include "asterisk/term.h"
#include "asterisk/cli.h"
#include "asterisk/utils.h"
#include "asterisk/manager.h"
#include "asterisk/threadstorage.h"
#include "asterisk/strings.h"
#include "asterisk/pbx.h"
#include "asterisk/app.h"
#include "asterisk/syslog.h"

#include <signal.h>
#include <time.h>
#include <sys/stat.h>
#include <fcntl.h>
#ifdef HAVE_BKTR
#include <execinfo.h>
#define MAX_BACKTRACE_FRAMES 20
#  if defined(HAVE_DLADDR) && defined(HAVE_BFD) && defined(BETTER_BACKTRACES)
#    include <dlfcn.h>
#    include <bfd.h>
#  endif
#endif

#if defined(__linux__) && !defined(__NR_gettid)
#include <asm/unistd.h>
#endif

#if defined(__linux__) && defined(__NR_gettid)
#define GETTID() syscall(__NR_gettid)
#else
#define GETTID() getpid()
#endif
static char dateformat[256] = "%b %e %T";    /* Original Asterisk Format */

static char queue_log_name[256] = QUEUELOG;
static char exec_after_rotate[256] = "";

static int filesize_reload_needed;
static unsigned int global_logmask = 0xFFFF;
static int queuelog_init;
static int logger_initialized;

static enum rotatestrategy {
   SEQUENTIAL = 1 << 0,     /* Original method - create a new file, in order */
   ROTATE = 1 << 1,         /* Rotate all files, such that the oldest file has the highest suffix */
   TIMESTAMP = 1 << 2,      /* Append the epoch timestamp onto the end of the archived file */
} rotatestrategy = SEQUENTIAL;

static struct {
   unsigned int queue_log:1;
   unsigned int queue_log_to_file:1;
   unsigned int queue_adaptive_realtime:1;
} logfiles = { 1 };

static char hostname[MAXHOSTNAMELEN];

enum logtypes {
   LOGTYPE_SYSLOG,
   LOGTYPE_FILE,
   LOGTYPE_CONSOLE,
};

struct logchannel {
   /*! What to log to this channel */
   unsigned int logmask;
   /*! If this channel is disabled or not */
   int disabled;
   /*! syslog facility */
   int facility;
   /*! Type of log channel */
   enum logtypes type;
   /*! logfile logging file pointer */
   FILE *fileptr;
   /*! Filename */
   char filename[PATH_MAX];
   /*! field for linking to list */
   AST_LIST_ENTRY(logchannel) list;
   /*! Line number from configuration file */
   int lineno;
   /*! Components (levels) from last config load */
   char components[0];
};

static AST_RWLIST_HEAD_STATIC(logchannels, logchannel);

enum logmsgtypes {
   LOGMSG_NORMAL = 0,
   LOGMSG_VERBOSE,
};

struct logmsg {
   enum logmsgtypes type;
   int level;
   int line;
   long process_id;
   AST_DECLARE_STRING_FIELDS(
      AST_STRING_FIELD(date);
      AST_STRING_FIELD(file);
      AST_STRING_FIELD(function);
      AST_STRING_FIELD(message);
      AST_STRING_FIELD(level_name);
   );
   AST_LIST_ENTRY(logmsg) list;
};

static AST_LIST_HEAD_STATIC(logmsgs, logmsg);
static pthread_t logthread = AST_PTHREADT_NULL;
static ast_cond_t logcond;
static int close_logger_thread = 0;

static FILE *qlog;

/*! \brief Logging channels used in the Asterisk logging system
 *
 * The first 16 levels are reserved for system usage, and the remaining
 * levels are reserved for usage by dynamic levels registered via
 * ast_logger_register_level.
 */

/* Modifications to this array are protected by the rwlock in the
 * logchannels list.
 */

static char *levels[NUMLOGLEVELS] = {
   "DEBUG",
   "---EVENT---",    /* no longer used */
   "NOTICE",
   "WARNING",
   "ERROR",
   "VERBOSE",
   "DTMF",
};

/*! \brief Colors used in the console for logging */
static const int colors[NUMLOGLEVELS] = {
   COLOR_BRGREEN,
   COLOR_BRBLUE,     /* no longer used */
   COLOR_YELLOW,
   COLOR_BRRED,
   COLOR_RED,
   COLOR_GREEN,
   COLOR_BRGREEN,
   0,
   0,
   0,
   0,
   0,
   0,
   0,
   0,
   0,
   COLOR_BRBLUE,
   COLOR_BRBLUE,
   COLOR_BRBLUE,
   COLOR_BRBLUE,
   COLOR_BRBLUE,
   COLOR_BRBLUE,
   COLOR_BRBLUE,
   COLOR_BRBLUE,
   COLOR_BRBLUE,
   COLOR_BRBLUE,
   COLOR_BRBLUE,
   COLOR_BRBLUE,
   COLOR_BRBLUE,
   COLOR_BRBLUE,
   COLOR_BRBLUE,
   COLOR_BRBLUE,
};

AST_THREADSTORAGE(verbose_buf);
#define VERBOSE_BUF_INIT_SIZE   256

AST_THREADSTORAGE(log_buf);
#define LOG_BUF_INIT_SIZE       256

static void logger_queue_init(void);

static unsigned int make_components(const char *s, int lineno)
{
   char *w;
   unsigned int res = 0;
   char *stringp = ast_strdupa(s);
   unsigned int x;

   while ((w = strsep(&stringp, ","))) {
      w = ast_skip_blanks(w);

      if (!strcmp(w, "*")) {
         res = 0xFFFFFFFF;
         break;
      } else for (x = 0; x < ARRAY_LEN(levels); x++) {
         if (levels[x] && !strcasecmp(w, levels[x])) {
            res |= (1 << x);
            break;
         }
      }
   }

   return res;
}

static struct logchannel *make_logchannel(const char *channel, const char *components, int lineno)
{
   struct logchannel *chan;
   char *facility;

   if (ast_strlen_zero(channel) || !(chan = ast_calloc(1, sizeof(*chan) + strlen(components) + 1)))
      return NULL;

   strcpy(chan->components, components);
   chan->lineno = lineno;

   if (!strcasecmp(channel, "console")) {
      chan->type = LOGTYPE_CONSOLE;
   } else if (!strncasecmp(channel, "syslog", 6)) {
      /*
      * syntax is:
      *  syslog.facility => level,level,level
      */
      facility = strchr(channel, '.');
      if (!facility++ || !facility) {
         facility = "local0";
      }

      chan->facility = ast_syslog_facility(facility);

      if (chan->facility < 0) {
         fprintf(stderr, "Logger Warning: bad syslog facility in logger.conf\n");
         ast_free(chan);
         return NULL;
      }

      chan->type = LOGTYPE_SYSLOG;
      ast_copy_string(chan->filename, channel, sizeof(chan->filename));
      openlog("asterisk", LOG_PID, chan->facility);
   } else {
      if (!ast_strlen_zero(hostname)) {
         snprintf(chan->filename, sizeof(chan->filename), "%s/%s.%s",
             channel[0] != '/' ? ast_config_AST_LOG_DIR : "", channel, hostname);
      } else {
         snprintf(chan->filename, sizeof(chan->filename), "%s/%s",
             channel[0] != '/' ? ast_config_AST_LOG_DIR : "", channel);
      }
      if (!(chan->fileptr = fopen(chan->filename, "a"))) {
         /* Can't do real logging here since we're called with a lock
          * so log to any attached consoles */
         ast_console_puts_mutable("ERROR: Unable to open log file '", __LOG_ERROR);
         ast_console_puts_mutable(chan->filename, __LOG_ERROR);
         ast_console_puts_mutable("': ", __LOG_ERROR);
         ast_console_puts_mutable(strerror(errno), __LOG_ERROR);
         ast_console_puts_mutable("'\n", __LOG_ERROR);
         ast_free(chan);
         return NULL;
      }
      chan->type = LOGTYPE_FILE;
   }
   chan->logmask = make_components(chan->components, lineno);

   return chan;
}

static void init_logger_chain(int locked)
{
   struct logchannel *chan;
   struct ast_config *cfg;
   struct ast_variable *var;
   const char *s;
   struct ast_flags config_flags = { 0 };

   if (!(cfg = ast_config_load2("logger.conf", "logger", config_flags)) || cfg == CONFIG_STATUS_FILEINVALID) {
      return;
   }

   /* delete our list of log channels */
   if (!locked) {
      AST_RWLIST_WRLOCK(&logchannels);
   }
   while ((chan = AST_RWLIST_REMOVE_HEAD(&logchannels, list))) {
      ast_free(chan);
   }
   global_logmask = 0;
   if (!locked) {
      AST_RWLIST_UNLOCK(&logchannels);
   }

   errno = 0;
   /* close syslog */
   closelog();

   /* If no config file, we're fine, set default options. */
   if (!cfg) {
      if (errno) {
         fprintf(stderr, "Unable to open logger.conf: %s; default settings will be used.\n", strerror(errno));
      } else {
         fprintf(stderr, "Errors detected in logger.conf: see above; default settings will be used.\n");
      }
      if (!(chan = ast_calloc(1, sizeof(*chan)))) {
         return;
      }
      chan->type = LOGTYPE_CONSOLE;
      chan->logmask = __LOG_WARNING | __LOG_NOTICE | __LOG_ERROR;
      if (!locked) {
         AST_RWLIST_WRLOCK(&logchannels);
      }
      AST_RWLIST_INSERT_HEAD(&logchannels, chan, list);
      global_logmask |= chan->logmask;
      if (!locked) {
         AST_RWLIST_UNLOCK(&logchannels);
      }
      return;
   }

   if ((s = ast_variable_retrieve(cfg, "general", "appendhostname"))) {
      if (ast_true(s)) {
         if (gethostname(hostname, sizeof(hostname) - 1)) {
            ast_copy_string(hostname, "unknown", sizeof(hostname));
            fprintf(stderr, "What box has no hostname???\n");
         }
      } else
         hostname[0] = '\0';
   } else
      hostname[0] = '\0';
   if ((s = ast_variable_retrieve(cfg, "general", "dateformat")))
      ast_copy_string(dateformat, s, sizeof(dateformat));
   else
      ast_copy_string(dateformat, "%b %e %T", sizeof(dateformat));
   if ((s = ast_variable_retrieve(cfg, "general", "queue_log"))) {
      logfiles.queue_log = ast_true(s);
   }
   if ((s = ast_variable_retrieve(cfg, "general", "queue_log_to_file"))) {
      logfiles.queue_log_to_file = ast_true(s);
   }
   if ((s = ast_variable_retrieve(cfg, "general", "queue_log_name"))) {
      ast_copy_string(queue_log_name, s, sizeof(queue_log_name));
   }
   if ((s = ast_variable_retrieve(cfg, "general", "exec_after_rotate"))) {
      ast_copy_string(exec_after_rotate, s, sizeof(exec_after_rotate));
   }
   if ((s = ast_variable_retrieve(cfg, "general", "rotatestrategy"))) {
      if (strcasecmp(s, "timestamp") == 0) {
         rotatestrategy = TIMESTAMP;
      } else if (strcasecmp(s, "rotate") == 0) {
         rotatestrategy = ROTATE;
      } else if (strcasecmp(s, "sequential") == 0) {
         rotatestrategy = SEQUENTIAL;
      } else {
         fprintf(stderr, "Unknown rotatestrategy: %s\n", s);
      }
   } else {
      if ((s = ast_variable_retrieve(cfg, "general", "rotatetimestamp"))) {
         rotatestrategy = ast_true(s) ? TIMESTAMP : SEQUENTIAL;
         fprintf(stderr, "rotatetimestamp option has been deprecated.  Please use rotatestrategy instead.\n");
      }
   }

   if (!locked) {
      AST_RWLIST_WRLOCK(&logchannels);
   }
   var = ast_variable_browse(cfg, "logfiles");
   for (; var; var = var->next) {
      if (!(chan = make_logchannel(var->name, var->value, var->lineno))) {
         /* Print error message directly to the consoles since the lock is held
          * and we don't want to unlock with the list partially built */
         ast_console_puts_mutable("ERROR: Unable to create log channel '", __LOG_ERROR);
         ast_console_puts_mutable(var->name, __LOG_ERROR);
         ast_console_puts_mutable("'\n", __LOG_ERROR);
         continue;
      }
      AST_RWLIST_INSERT_HEAD(&logchannels, chan, list);
      global_logmask |= chan->logmask;
   }

   if (qlog) {
      fclose(qlog);
      qlog = NULL;
   }

   if (!locked) {
      AST_RWLIST_UNLOCK(&logchannels);
   }

   ast_config_destroy(cfg);
}

void ast_child_verbose(int level, const char *fmt, ...)
{
   char *msg = NULL, *emsg = NULL, *sptr, *eptr;
   va_list ap, aq;
   int size;

   /* Don't bother, if the level isn't that high */
   if (option_verbose < level) {
      return;
   }

   va_start(ap, fmt);
   va_copy(aq, ap);
   if ((size = vsnprintf(msg, 0, fmt, ap)) < 0) {
      va_end(ap);
      va_end(aq);
      return;
   }
   va_end(ap);

   if (!(msg = ast_malloc(size + 1))) {
      va_end(aq);
      return;
   }

   vsnprintf(msg, size + 1, fmt, aq);
   va_end(aq);

   if (!(emsg = ast_malloc(size * 2 + 1))) {
      ast_free(msg);
      return;
   }

   for (sptr = msg, eptr = emsg; ; sptr++) {
      if (*sptr == '"') {
         *eptr++ = '\\';
      }
      *eptr++ = *sptr;
      if (*sptr == '\0') {
         break;
      }
   }
   ast_free(msg);

   fprintf(stdout, "verbose \"%s\" %d\n", emsg, level);
   fflush(stdout);
   ast_free(emsg);
}

void ast_queue_log(const char *queuename, const char *callid, const char *agent, const char *event, const char *fmt, ...)
{
   va_list ap;
   struct timeval tv;
   struct ast_tm tm;
   char qlog_msg[8192];
   int qlog_len;
   char time_str[30];

   if (!logger_initialized) {
      /* You are too early.  We are not open yet! */
      return;
   }
   if (!queuelog_init) {
      AST_RWLIST_WRLOCK(&logchannels);
      if (!queuelog_init) {
         /*
          * We have delayed initializing the queue logging system so
          * preloaded realtime modules can get up.  We must initialize
          * now since someone is trying to log something.
          */
         logger_queue_init();
         queuelog_init = 1;
         AST_RWLIST_UNLOCK(&logchannels);
         ast_queue_log("NONE", "NONE", "NONE", "QUEUESTART", "%s", "");
      } else {
         AST_RWLIST_UNLOCK(&logchannels);
      }
   }

   if (ast_check_realtime("queue_log")) {
      tv = ast_tvnow();
      ast_localtime(&tv, &tm, NULL);
      ast_strftime(time_str, sizeof(time_str), "%F %T.%6q", &tm);
      va_start(ap, fmt);
      vsnprintf(qlog_msg, sizeof(qlog_msg), fmt, ap);
      va_end(ap);
      if (logfiles.queue_adaptive_realtime) {
         AST_DECLARE_APP_ARGS(args,
            AST_APP_ARG(data)[5];
         );
         AST_NONSTANDARD_APP_ARGS(args, qlog_msg, '|');
         /* Ensure fields are large enough to receive data */
         ast_realtime_require_field("queue_log",
            "data1", RQ_CHAR, strlen(S_OR(args.data[0], "")),
            "data2", RQ_CHAR, strlen(S_OR(args.data[1], "")),
            "data3", RQ_CHAR, strlen(S_OR(args.data[2], "")),
            "data4", RQ_CHAR, strlen(S_OR(args.data[3], "")),
            "data5", RQ_CHAR, strlen(S_OR(args.data[4], "")),
            SENTINEL);

         /* Store the log */
         ast_store_realtime("queue_log", "time", time_str,
            "callid", callid,
            "queuename", queuename,
            "agent", agent,
            "event", event,
            "data1", S_OR(args.data[0], ""),
            "data2", S_OR(args.data[1], ""),
            "data3", S_OR(args.data[2], ""),
            "data4", S_OR(args.data[3], ""),
            "data5", S_OR(args.data[4], ""),
            SENTINEL);
      } else {
         ast_store_realtime("queue_log", "time", time_str,
            "callid", callid,
            "queuename", queuename,
            "agent", agent,
            "event", event,
            "data", qlog_msg,
            SENTINEL);
      }

      if (!logfiles.queue_log_to_file) {
         return;
      }
   }

   if (qlog) {
      va_start(ap, fmt);
      qlog_len = snprintf(qlog_msg, sizeof(qlog_msg), "%ld|%s|%s|%s|%s|", (long)time(NULL), callid, queuename, agent, event);
      vsnprintf(qlog_msg + qlog_len, sizeof(qlog_msg) - qlog_len, fmt, ap);
      va_end(ap);
      AST_RWLIST_RDLOCK(&logchannels);
      if (qlog) {
         fprintf(qlog, "%s\n", qlog_msg);
         fflush(qlog);
      }
      AST_RWLIST_UNLOCK(&logchannels);
   }
}

static int rotate_file(const char *filename)
{
   char old[PATH_MAX];
   char new[PATH_MAX];
   int x, y, which, found, res = 0, fd;
   char *suffixes[4] = { "", ".gz", ".bz2", ".Z" };

   switch (rotatestrategy) {
   case SEQUENTIAL:
      for (x = 0; ; x++) {
         snprintf(new, sizeof(new), "%s.%d", filename, x);
         fd = open(new, O_RDONLY);
         if (fd > -1)
            close(fd);
         else
            break;
      }
      if (rename(filename, new)) {
         fprintf(stderr, "Unable to rename file '%s' to '%s'\n", filename, new);
         res = -1;
      } else {
         filename = new;
      }
      break;
   case TIMESTAMP:
      snprintf(new, sizeof(new), "%s.%ld", filename, (long)time(NULL));
      if (rename(filename, new)) {
         fprintf(stderr, "Unable to rename file '%s' to '%s'\n", filename, new);
         res = -1;
      } else {
         filename = new;
      }
      break;
   case ROTATE:
      /* Find the next empty slot, including a possible suffix */
      for (x = 0; ; x++) {
         found = 0;
         for (which = 0; which < ARRAY_LEN(suffixes); which++) {
            snprintf(new, sizeof(new), "%s.%d%s", filename, x, suffixes[which]);
            fd = open(new, O_RDONLY);
            if (fd > -1) {
               close(fd);
               found = 1;
               break;
            }
         }
         if (!found) {
            break;
         }
      }

      /* Found an empty slot */
      for (y = x; y > 0; y--) {
         for (which = 0; which < ARRAY_LEN(suffixes); which++) {
            snprintf(old, sizeof(old), "%s.%d%s", filename, y - 1, suffixes[which]);
            fd = open(old, O_RDONLY);
            if (fd > -1) {
               /* Found the right suffix */
               close(fd);
               snprintf(new, sizeof(new), "%s.%d%s", filename, y, suffixes[which]);
               if (rename(old, new)) {
                  fprintf(stderr, "Unable to rename file '%s' to '%s'\n", old, new);
                  res = -1;
               }
               break;
            }
         }
      }

      /* Finally, rename the current file */
      snprintf(new, sizeof(new), "%s.0", filename);
      if (rename(filename, new)) {
         fprintf(stderr, "Unable to rename file '%s' to '%s'\n", filename, new);
         res = -1;
      } else {
         filename = new;
      }
   }

   if (!ast_strlen_zero(exec_after_rotate)) {
      struct ast_channel *c = ast_dummy_channel_alloc();
      char buf[512];

      pbx_builtin_setvar_helper(c, "filename", filename);
      pbx_substitute_variables_helper(c, exec_after_rotate, buf, sizeof(buf));
      if (c) {
         c = ast_channel_unref(c);
      }
      if (ast_safe_system(buf) == -1) {
         ast_log(LOG_WARNING, "error executing '%s'\n", buf);
      }
   }
   return res;
}

/*!
 * \internal
 * \brief Start the realtime queue logging if configured.
 *
 * \retval TRUE if not to open queue log file.
 */
static int logger_queue_rt_start(void)
{
   if (ast_check_realtime("queue_log")) {
      if (!ast_realtime_require_field("queue_log",
         "time", RQ_DATETIME, 26,
         "data1", RQ_CHAR, 20,
         "data2", RQ_CHAR, 20,
         "data3", RQ_CHAR, 20,
         "data4", RQ_CHAR, 20,
         "data5", RQ_CHAR, 20,
         SENTINEL)) {
         logfiles.queue_adaptive_realtime = 1;
      } else {
         logfiles.queue_adaptive_realtime = 0;
      }

      if (!logfiles.queue_log_to_file) {
         /* Don't open the log file. */
         return 1;
      }
   }
   return 0;
}

/*!
 * \internal
 * \brief Rotate the queue log file and restart.
 *
 * \param queue_rotate Log queue rotation mode.
 *
 * \note Assumes logchannels is write locked on entry.
 *
 * \retval 0 on success.
 * \retval -1 on error.
 */
static int logger_queue_restart(int queue_rotate)
{
   int res = 0;
   char qfname[PATH_MAX];

   if (logger_queue_rt_start()) {
      return res;
   }

   snprintf(qfname, sizeof(qfname), "%s/%s", ast_config_AST_LOG_DIR, queue_log_name);
   if (qlog) {
      /* Just in case it was still open. */
      fclose(qlog);
      qlog = NULL;
   }
   if (queue_rotate) {
      rotate_file(qfname);
   }

   /* Open the log file. */
   qlog = fopen(qfname, "a");
   if (!qlog) {
      ast_log(LOG_ERROR, "Unable to create queue log: %s\n", strerror(errno));
      res = -1;
   }
   return res;
}

static int reload_logger(int rotate)
{
   int queue_rotate = rotate;
   struct logchannel *f;
   int res = 0;

   AST_RWLIST_WRLOCK(&logchannels);

   if (qlog) {
      if (rotate < 0) {
         /* Check filesize - this one typically doesn't need an auto-rotate */
         if (ftello(qlog) > 0x40000000) { /* Arbitrarily, 1 GB */
            fclose(qlog);
            qlog = NULL;
         } else {
            queue_rotate = 0;
         }
      } else {
         fclose(qlog);
         qlog = NULL;
      }
   } else {
      queue_rotate = 0;
   }

   ast_mkdir(ast_config_AST_LOG_DIR, 0777);

   AST_RWLIST_TRAVERSE(&logchannels, f, list) {
      if (f->disabled) {
         f->disabled = 0;  /* Re-enable logging at reload */
         manager_event(EVENT_FLAG_SYSTEM, "LogChannel", "Channel: %s\r\nEnabled: Yes\r\n", f->filename);
      }
      if (f->fileptr && (f->fileptr != stdout) && (f->fileptr != stderr)) {
         int rotate_this = 0;
         if (ftello(f->fileptr) > 0x40000000) { /* Arbitrarily, 1 GB */
            /* Be more proactive about rotating massive log files */
            rotate_this = 1;
         }
         fclose(f->fileptr);  /* Close file */
         f->fileptr = NULL;
         if (rotate || rotate_this) {
            rotate_file(f->filename);
         }
      }
   }

   filesize_reload_needed = 0;

   init_logger_chain(1 /* locked */);

   ast_unload_realtime("queue_log");
   if (logfiles.queue_log) {
      res = logger_queue_restart(queue_rotate);
      AST_RWLIST_UNLOCK(&logchannels);
      ast_queue_log("NONE", "NONE", "NONE", "CONFIGRELOAD", "%s", "");
      ast_verb(1, "Asterisk Queue Logger restarted\n");
   } else {
      AST_RWLIST_UNLOCK(&logchannels);
   }

   return res;
}

/*! \brief Reload the logger module without rotating log files (also used from loader.c during
   a full Asterisk reload) */
int logger_reload(void)
{
   if (reload_logger(0)) {
      return RESULT_FAILURE;
   }
   return RESULT_SUCCESS;
}

static char *handle_logger_reload(struct ast_cli_entry *e, int cmd, struct ast_cli_args *a)
{
   switch (cmd) {
   case CLI_INIT:
      e->command = "logger reload";
      e->usage = 
         "Usage: logger reload\n"
         "       Reloads the logger subsystem state.  Use after restarting syslogd(8) if you are using syslog logging.\n";
      return NULL;
   case CLI_GENERATE:
      return NULL;
   }
   if (reload_logger(0)) {
      ast_cli(a->fd, "Failed to reload the logger\n");
      return CLI_FAILURE;
   }
   return CLI_SUCCESS;
}

static char *handle_logger_rotate(struct ast_cli_entry *e, int cmd, struct ast_cli_args *a)
{
   switch (cmd) {
   case CLI_INIT:
      e->command = "logger rotate";
      e->usage = 
         "Usage: logger rotate\n"
         "       Rotates and Reopens the log files.\n";
      return NULL;
   case CLI_GENERATE:
      return NULL;   
   }
   if (reload_logger(1)) {
      ast_cli(a->fd, "Failed to reload the logger and rotate log files\n");
      return CLI_FAILURE;
   } 
   return CLI_SUCCESS;
}

static char *handle_logger_set_level(struct ast_cli_entry *e, int cmd, struct ast_cli_args *a)
{
   int x;
   int state;
   int level = -1;

   switch (cmd) {
   case CLI_INIT:
      e->command = "logger set level {DEBUG|NOTICE|WARNING|ERROR|VERBOSE|DTMF} {on|off}";
      e->usage = 
         "Usage: logger set level {DEBUG|NOTICE|WARNING|ERROR|VERBOSE|DTMF} {on|off}\n"
         "       Set a specific log level to enabled/disabled for this console.\n";
      return NULL;
   case CLI_GENERATE:
      return NULL;
   }

   if (a->argc < 5)
      return CLI_SHOWUSAGE;

   AST_RWLIST_WRLOCK(&logchannels);

   for (x = 0; x < ARRAY_LEN(levels); x++) {
      if (levels[x] && !strcasecmp(a->argv[3], levels[x])) {
         level = x;
         break;
      }
   }

   AST_RWLIST_UNLOCK(&logchannels);

   state = ast_true(a->argv[4]) ? 1 : 0;

   if (level != -1) {
      ast_console_toggle_loglevel(a->fd, level, state);
      ast_cli(a->fd, "Logger status for '%s' has been set to '%s'.\n", levels[level], state ? "on" : "off");
   } else
      return CLI_SHOWUSAGE;

   return CLI_SUCCESS;
}

/*! \brief CLI command to show logging system configuration */
static char *handle_logger_show_channels(struct ast_cli_entry *e, int cmd, struct ast_cli_args *a)
{
#define FORMATL   "%-35.35s %-8.8s %-9.9s "
   struct logchannel *chan;
   switch (cmd) {
   case CLI_INIT:
      e->command = "logger show channels";
      e->usage = 
         "Usage: logger show channels\n"
         "       List configured logger channels.\n";
      return NULL;
   case CLI_GENERATE:
      return NULL;   
   }
   ast_cli(a->fd, FORMATL, "Channel", "Type", "Status");
   ast_cli(a->fd, "Configuration\n");
   ast_cli(a->fd, FORMATL, "-------", "----", "------");
   ast_cli(a->fd, "-------------\n");
   AST_RWLIST_RDLOCK(&logchannels);
   AST_RWLIST_TRAVERSE(&logchannels, chan, list) {
      unsigned int level;

      ast_cli(a->fd, FORMATL, chan->filename, chan->type == LOGTYPE_CONSOLE ? "Console" : (chan->type == LOGTYPE_SYSLOG ? "Syslog" : "File"),
         chan->disabled ? "Disabled" : "Enabled");
      ast_cli(a->fd, " - ");
      for (level = 0; level < ARRAY_LEN(levels); level++) {
         if ((chan->logmask & (1 << level)) && levels[level]) {
            ast_cli(a->fd, "%s ", levels[level]);
         }
      }
      ast_cli(a->fd, "\n");
   }
   AST_RWLIST_UNLOCK(&logchannels);
   ast_cli(a->fd, "\n");

   return CLI_SUCCESS;
}

struct verb {
   void (*verboser)(const char *string);
   AST_LIST_ENTRY(verb) list;
};

static AST_RWLIST_HEAD_STATIC(verbosers, verb);

static struct ast_cli_entry cli_logger[] = {
   AST_CLI_DEFINE(handle_logger_show_channels, "List configured log channels"),
   AST_CLI_DEFINE(handle_logger_reload, "Reopens the log files"),
   AST_CLI_DEFINE(handle_logger_rotate, "Rotates and reopens the log files"),
   AST_CLI_DEFINE(handle_logger_set_level, "Enables/Disables a specific logging level for this console")
};

static void _handle_SIGXFSZ(int sig)
{
   /* Indicate need to reload */
   filesize_reload_needed = 1;
}

static struct sigaction handle_SIGXFSZ = {
   .sa_handler = _handle_SIGXFSZ,
   .sa_flags = SA_RESTART,
};

static void ast_log_vsyslog(struct logmsg *msg)
{
   char buf[BUFSIZ];
   int syslog_level = ast_syslog_priority_from_loglevel(msg->level);

   if (syslog_level < 0) {
      /* we are locked here, so cannot ast_log() */
      fprintf(stderr, "ast_log_vsyslog called with bogus level: %d\n", msg->level);
      return;
   }

   snprintf(buf, sizeof(buf), "%s[%ld]: %s:%d in %s: %s",
       levels[msg->level], msg->process_id, msg->file, msg->line, msg->function, msg->message);

   term_strip(buf, buf, strlen(buf) + 1);
   syslog(syslog_level, "%s", buf);
}

/*! \brief Print a normal log message to the channels */
static void logger_print_normal(struct logmsg *logmsg)
{
   struct logchannel *chan = NULL;
   char buf[BUFSIZ];
   struct verb *v = NULL;

   if (logmsg->level == __LOG_VERBOSE) {
      char *tmpmsg = ast_strdupa(logmsg->message + 1);
      /* Iterate through the list of verbosers and pass them the log message string */
      AST_RWLIST_RDLOCK(&verbosers);
      AST_RWLIST_TRAVERSE(&verbosers, v, list)
         v->verboser(logmsg->message);
      AST_RWLIST_UNLOCK(&verbosers);
      ast_string_field_set(logmsg, message, tmpmsg);
   }

   AST_RWLIST_RDLOCK(&logchannels);

   if (!AST_RWLIST_EMPTY(&logchannels)) {
      AST_RWLIST_TRAVERSE(&logchannels, chan, list) {
         /* If the channel is disabled, then move on to the next one */
         if (chan->disabled)
            continue;
         /* Check syslog channels */
         if (chan->type == LOGTYPE_SYSLOG && (chan->logmask & (1 << logmsg->level))) {
            ast_log_vsyslog(logmsg);
         /* Console channels */
         } else if (chan->type == LOGTYPE_CONSOLE && (chan->logmask & (1 << logmsg->level))) {
            char linestr[128];
            char tmp1[80], tmp2[80], tmp3[80], tmp4[80];

            /* If the level is verbose, then skip it */
            if (logmsg->level == __LOG_VERBOSE)
               continue;

            /* Turn the numerical line number into a string */
            snprintf(linestr, sizeof(linestr), "%d", logmsg->line);
            /* Build string to print out */
            snprintf(buf, sizeof(buf), "[%s] %s[%ld]: %s:%s %s: %s",
                logmsg->date,
                term_color(tmp1, logmsg->level_name, colors[logmsg->level], 0, sizeof(tmp1)),
                logmsg->process_id,
                term_color(tmp2, logmsg->file, COLOR_BRWHITE, 0, sizeof(tmp2)),
                term_color(tmp3, linestr, COLOR_BRWHITE, 0, sizeof(tmp3)),
                term_color(tmp4, logmsg->function, COLOR_BRWHITE, 0, sizeof(tmp4)),
                logmsg->message);
            /* Print out */
            ast_console_puts_mutable(buf, logmsg->level);
         /* File channels */
         } else if (chan->type == LOGTYPE_FILE && (chan->logmask & (1 << logmsg->level))) {
            int res = 0;

            /* If no file pointer exists, skip it */
            if (!chan->fileptr) {
               continue;
            }

            /* Print out to the file */
            res = fprintf(chan->fileptr, "[%s] %s[%ld] %s: %s",
                     logmsg->date, logmsg->level_name, logmsg->process_id, logmsg->file, term_strip(buf, logmsg->message, BUFSIZ));
            if (res <= 0 && !ast_strlen_zero(logmsg->message)) {
               fprintf(stderr, "**** Asterisk Logging Error: ***********\n");
               if (errno == ENOMEM || errno == ENOSPC)
                  fprintf(stderr, "Asterisk logging error: Out of disk space, can't log to log file %s\n", chan->filename);
               else
                  fprintf(stderr, "Logger Warning: Unable to write to log file '%s': %s (disabled)\n", chan->filename, strerror(errno));
               manager_event(EVENT_FLAG_SYSTEM, "LogChannel", "Channel: %s\r\nEnabled: No\r\nReason: %d - %s\r\n", chan->filename, errno, strerror(errno));
               chan->disabled = 1;
            } else if (res > 0) {
               fflush(chan->fileptr);
            }
         }
      }
   } else if (logmsg->level != __LOG_VERBOSE) {
      fputs(logmsg->message, stdout);
   }

   AST_RWLIST_UNLOCK(&logchannels);

   /* If we need to reload because of the file size, then do so */
   if (filesize_reload_needed) {
      reload_logger(-1);
      ast_verb(1, "Rotated Logs Per SIGXFSZ (Exceeded file size limit)\n");
   }

   return;
}

/*! \brief Actual logging thread */
static void *logger_thread(void *data)
{
   struct logmsg *next = NULL, *msg = NULL;

   for (;;) {
      /* We lock the message list, and see if any message exists... if not we wait on the condition to be signalled */
      AST_LIST_LOCK(&logmsgs);
      if (AST_LIST_EMPTY(&logmsgs)) {
         if (close_logger_thread) {
            AST_LIST_UNLOCK(&logmsgs);
            break;
         } else {
            ast_cond_wait(&logcond, &logmsgs.lock);
         }
      }
      next = AST_LIST_FIRST(&logmsgs);
      AST_LIST_HEAD_INIT_NOLOCK(&logmsgs);
      AST_LIST_UNLOCK(&logmsgs);

      /* Otherwise go through and process each message in the order added */
      while ((msg = next)) {
         /* Get the next entry now so that we can free our current structure later */
         next = AST_LIST_NEXT(msg, list);

         /* Depending on the type, send it to the proper function */
         logger_print_normal(msg);

         /* Free the data since we are done */
         ast_free(msg);
      }

      /* If we should stop, then stop */
      if (close_logger_thread)
         break;
   }

   return NULL;
}

/*!
 * \internal
 * \brief Initialize the logger queue.
 *
 * \note Assumes logchannels is write locked on entry.
 *
 * \return Nothing
 */
static void logger_queue_init(void)
{
   ast_unload_realtime("queue_log");
   if (logfiles.queue_log) {
      char qfname[PATH_MAX];

      if (logger_queue_rt_start()) {
         return;
      }

      /* Open the log file. */
      snprintf(qfname, sizeof(qfname), "%s/%s", ast_config_AST_LOG_DIR,
         queue_log_name);
      if (qlog) {
         /* Just in case it was already open. */
         fclose(qlog);
      }
      qlog = fopen(qfname, "a");
      if (!qlog) {
         ast_log(LOG_ERROR, "Unable to create queue log: %s\n", strerror(errno));
      }
   }
}

int init_logger(void)
{
   /* auto rotate if sig SIGXFSZ comes a-knockin */
   sigaction(SIGXFSZ, &handle_SIGXFSZ, NULL);

   /* start logger thread */
   ast_cond_init(&logcond, NULL);
   if (ast_pthread_create(&logthread, NULL, logger_thread, NULL) < 0) {
      ast_cond_destroy(&logcond);
      return -1;
   }

   /* register the logger cli commands */
   ast_cli_register_multiple(cli_logger, ARRAY_LEN(cli_logger));

   ast_mkdir(ast_config_AST_LOG_DIR, 0777);

   /* create log channels */
   init_logger_chain(0 /* locked */);
   logger_initialized = 1;

   return 0;
}

void close_logger(void)
{
   struct logchannel *f = NULL;

   logger_initialized = 0;

   /* Stop logger thread */
   AST_LIST_LOCK(&logmsgs);
   close_logger_thread = 1;
   ast_cond_signal(&logcond);
   AST_LIST_UNLOCK(&logmsgs);

   if (logthread != AST_PTHREADT_NULL)
      pthread_join(logthread, NULL);

   AST_RWLIST_WRLOCK(&logchannels);

   if (qlog) {
      fclose(qlog);
      qlog = NULL;
   }

   AST_RWLIST_TRAVERSE(&logchannels, f, list) {
      if (f->fileptr && (f->fileptr != stdout) && (f->fileptr != stderr)) {
         fclose(f->fileptr);
         f->fileptr = NULL;
      }
   }

   closelog(); /* syslog */

   AST_RWLIST_UNLOCK(&logchannels);
}

/*!
 * \brief send log messages to syslog and/or the console
 */
void ast_log(int level, const char *file, int line, const char *function, const char *fmt, ...)
{
   struct logmsg *logmsg = NULL;
   struct ast_str *buf = NULL;
   struct ast_tm tm;
   struct timeval now = ast_tvnow();
   int res = 0;
   va_list ap;
   char datestring[256];

   if (!(buf = ast_str_thread_get(&log_buf, LOG_BUF_INIT_SIZE)))
      return;

   if (level != __LOG_VERBOSE && AST_RWLIST_EMPTY(&logchannels)) {
      /*
       * we don't have the logger chain configured yet,
       * so just log to stdout
       */
      int result;
      va_start(ap, fmt);
      result = ast_str_set_va(&buf, BUFSIZ, fmt, ap); /* XXX BUFSIZ ? */
      va_end(ap);
      if (result != AST_DYNSTR_BUILD_FAILED) {
         term_filter_escapes(ast_str_buffer(buf));
         fputs(ast_str_buffer(buf), stdout);
      }
      return;
   }
   
   /* don't display LOG_DEBUG messages unless option_verbose _or_ option_debug
      are non-zero; LOG_DEBUG messages can still be displayed if option_debug
      is zero, if option_verbose is non-zero (this allows for 'level zero'
      LOG_DEBUG messages to be displayed, if the logmask on any channel
      allows it)
   */
   if (!option_verbose && !option_debug && (level == __LOG_DEBUG))
      return;

   /* Ignore anything that never gets logged anywhere */
   if (level != __LOG_VERBOSE && !(global_logmask & (1 << level)))
      return;
   
   /* Build string */
   va_start(ap, fmt);
   res = ast_str_set_va(&buf, BUFSIZ, fmt, ap);
   va_end(ap);

   /* If the build failed, then abort and free this structure */
   if (res == AST_DYNSTR_BUILD_FAILED)
      return;

   /* Create a new logging message */
   if (!(logmsg = ast_calloc_with_stringfields(1, struct logmsg, res + 128)))
      return;

   /* Copy string over */
   ast_string_field_set(logmsg, message, ast_str_buffer(buf));

   /* Set type */
   if (level == __LOG_VERBOSE) {
      logmsg->type = LOGMSG_VERBOSE;
   } else {
      logmsg->type = LOGMSG_NORMAL;
   }

   /* Create our date/time */
   ast_localtime(&now, &tm, NULL);
   ast_strftime(datestring, sizeof(datestring), dateformat, &tm);
   ast_string_field_set(logmsg, date, datestring);

   /* Copy over data */
   logmsg->level = level;
   logmsg->line = line;
   ast_string_field_set(logmsg, level_name, levels[level]);
   ast_string_field_set(logmsg, file, file);
   ast_string_field_set(logmsg, function, function);
   logmsg->process_id = (long) GETTID();

   /* If the logger thread is active, append it to the tail end of the list - otherwise skip that step */
   if (logthread != AST_PTHREADT_NULL) {
      AST_LIST_LOCK(&logmsgs);
      if (close_logger_thread) {
         /* Logger is either closing or closed.  We cannot log this message. */
         ast_free(logmsg);
      } else {
         AST_LIST_INSERT_TAIL(&logmsgs, logmsg, list);
         ast_cond_signal(&logcond);
      }
      AST_LIST_UNLOCK(&logmsgs);
   } else {
      logger_print_normal(logmsg);
      ast_free(logmsg);
   }
}

#ifdef HAVE_BKTR

struct ast_bt *ast_bt_create(void) 
{
   struct ast_bt *bt = ast_calloc(1, sizeof(*bt));
   if (!bt) {
      ast_log(LOG_ERROR, "Unable to allocate memory for backtrace structure!\n");
      return NULL;
   }

   bt->alloced = 1;

   ast_bt_get_addresses(bt);

   return bt;
}

int ast_bt_get_addresses(struct ast_bt *bt)
{
   bt->num_frames = backtrace(bt->addresses, AST_MAX_BT_FRAMES);

   return 0;
}

void *ast_bt_destroy(struct ast_bt *bt)
{
   if (bt->alloced) {
      ast_free(bt);
   }

   return NULL;
}

char **ast_bt_get_symbols(void **addresses, size_t num_frames)
{
   char **strings = NULL;
#if defined(BETTER_BACKTRACES)
   int stackfr;
   bfd *bfdobj;           /* bfd.h */
   Dl_info dli;           /* dlfcn.h */
   long allocsize;
   asymbol **syms = NULL; /* bfd.h */
   bfd_vma offset;        /* bfd.h */
   const char *lastslash;
   asection *section;
   const char *file, *func;
   unsigned int line;
   char address_str[128];
   char msg[1024];
   size_t strings_size;
   size_t *eachlen;
#endif

#if defined(BETTER_BACKTRACES)
   strings_size = num_frames * sizeof(*strings);
   eachlen = ast_calloc(num_frames, sizeof(*eachlen));

   if (!(strings = ast_calloc(num_frames, sizeof(*strings)))) {
      return NULL;
   }

   for (stackfr = 0; stackfr < num_frames; stackfr++) {
      int found = 0, symbolcount;

      msg[0] = '\0';

      if (!dladdr(addresses[stackfr], &dli)) {
         continue;
      }

      if (strcmp(dli.dli_fname, "asterisk") == 0) {
         char asteriskpath[256];
         if (!(dli.dli_fname = ast_utils_which("asterisk", asteriskpath, sizeof(asteriskpath)))) {
            /* This will fail to find symbols */
            ast_log(LOG_DEBUG, "Failed to find asterisk binary for debug symbols.\n");
            dli.dli_fname = "asterisk";
         }
      }

      lastslash = strrchr(dli.dli_fname, '/');
      if (  (bfdobj = bfd_openr(dli.dli_fname, NULL)) &&
            bfd_check_format(bfdobj, bfd_object) &&
            (allocsize = bfd_get_symtab_upper_bound(bfdobj)) > 0 &&
            (syms = ast_malloc(allocsize)) &&
            (symbolcount = bfd_canonicalize_symtab(bfdobj, syms))) {

         if (bfdobj->flags & DYNAMIC) {
            offset = addresses[stackfr] - dli.dli_fbase;
         } else {
            offset = addresses[stackfr] - (void *) 0;
         }

         for (section = bfdobj->sections; section; section = section->next) {
            if (  !bfd_get_section_flags(bfdobj, section) & SEC_ALLOC ||
                  section->vma > offset ||
                  section->size + section->vma < offset) {
               continue;
            }

            if (!bfd_find_nearest_line(bfdobj, section, syms, offset - section->vma, &file, &func, &line)) {
               continue;
            }

            /* Stack trace output */
            found++;
            if ((lastslash = strrchr(file, '/'))) {
               const char *prevslash;
               for (prevslash = lastslash - 1; *prevslash != '/' && prevslash >= file; prevslash--);
               if (prevslash >= file) {
                  lastslash = prevslash;
               }
            }
            if (dli.dli_saddr == NULL) {
               address_str[0] = '\0';
            } else {
               snprintf(address_str, sizeof(address_str), " (%p+%lX)",
                  dli.dli_saddr,
                  (unsigned long) (addresses[stackfr] - dli.dli_saddr));
            }
            snprintf(msg, sizeof(msg), "%s:%u %s()%s",
               lastslash ? lastslash + 1 : file, line,
               S_OR(func, "???"),
               address_str);

            break; /* out of section iteration */
         }
      }
      if (bfdobj) {
         bfd_close(bfdobj);
         if (syms) {
            ast_free(syms);
         }
      }

      /* Default output, if we cannot find the information within BFD */
      if (!found) {
         if (dli.dli_saddr == NULL) {
            address_str[0] = '\0';
         } else {
            snprintf(address_str, sizeof(address_str), " (%p+%lX)",
               dli.dli_saddr,
               (unsigned long) (addresses[stackfr] - dli.dli_saddr));
         }
         snprintf(msg, sizeof(msg), "%s %s()%s",
            lastslash ? lastslash + 1 : dli.dli_fname,
            S_OR(dli.dli_sname, "<unknown>"),
            address_str);
      }

      if (!ast_strlen_zero(msg)) {
         char **tmp;
         eachlen[stackfr] = strlen(msg);
         if (!(tmp = ast_realloc(strings, strings_size + eachlen[stackfr] + 1))) {
            ast_free(strings);
            strings = NULL;
            break; /* out of stack frame iteration */
         }
         strings = tmp;
         strings[stackfr] = (char *) strings + strings_size;
         ast_copy_string(strings[stackfr], msg, eachlen[stackfr] + 1);
         strings_size += eachlen[stackfr] + 1;
      }
   }

   if (strings) {
      /* Recalculate the offset pointers */
      strings[0] = (char *) strings + num_frames * sizeof(*strings);
      for (stackfr = 1; stackfr < num_frames; stackfr++) {
         strings[stackfr] = strings[stackfr - 1] + eachlen[stackfr - 1] + 1;
      }
   }
#else /* !defined(BETTER_BACKTRACES) */
   strings = backtrace_symbols(addresses, num_frames);
#endif /* defined(BETTER_BACKTRACES) */
   return strings;
}

#endif /* HAVE_BKTR */

void ast_backtrace(void)
{
#ifdef HAVE_BKTR
   struct ast_bt *bt;
   int i = 0;
   char **strings;

   if (!(bt = ast_bt_create())) {
      ast_log(LOG_WARNING, "Unable to allocate space for backtrace structure\n");
      return;
   }

   if ((strings = ast_bt_get_symbols(bt->addresses, bt->num_frames))) {
      ast_debug(1, "Got %d backtrace record%c\n", bt->num_frames, bt->num_frames != 1 ? 's' : ' ');
      for (i = 3; i < bt->num_frames - 2; i++) {
         ast_log(LOG_DEBUG, "#%d: [%p] %s\n", i - 3, bt->addresses[i], strings[i]);
      }

      /* MALLOC_DEBUG will erroneously report an error here, unless we undef the macro. */
#undef free
      free(strings);
   } else {
      ast_debug(1, "Could not allocate memory for backtrace\n");
   }
   ast_bt_destroy(bt);
#else
   ast_log(LOG_WARNING, "Must run configure with '--with-execinfo' for stack backtraces.\n");
#endif /* defined(HAVE_BKTR) */
}

void __ast_verbose_ap(const char *file, int line, const char *func, const char *fmt, va_list ap)
{
   struct ast_str *buf = NULL;
   int res = 0;

   if (!(buf = ast_str_thread_get(&verbose_buf, VERBOSE_BUF_INIT_SIZE)))
      return;

   if (ast_opt_timestamp) {
      struct timeval now;
      struct ast_tm tm;
      char date[40];
      char *datefmt;

      now = ast_tvnow();
      ast_localtime(&now, &tm, NULL);
      ast_strftime(date, sizeof(date), dateformat, &tm);
      datefmt = alloca(strlen(date) + 3 + strlen(fmt) + 1);
      sprintf(datefmt, "%c[%s] %s", 127, date, fmt);
      fmt = datefmt;
   } else {
      char *tmp = alloca(strlen(fmt) + 2);
      sprintf(tmp, "%c%s", 127, fmt);
      fmt = tmp;
   }

   /* Build string */
   res = ast_str_set_va(&buf, 0, fmt, ap);

   /* If the build failed then we can drop this allocated message */
   if (res == AST_DYNSTR_BUILD_FAILED)
      return;

   ast_log(__LOG_VERBOSE, file, line, func, "%s", ast_str_buffer(buf));
}

void __ast_verbose(const char *file, int line, const char *func, const char *fmt, ...)
{
   va_list ap;

   va_start(ap, fmt);
   __ast_verbose_ap(file, line, func, fmt, ap);
   va_end(ap);
}

/* No new code should use this directly, but we have the ABI for backwards compat */
#undef ast_verbose
void __attribute__((format(printf, 1,2))) ast_verbose(const char *fmt, ...);
void ast_verbose(const char *fmt, ...)
{
   va_list ap;

   va_start(ap, fmt);
   __ast_verbose_ap("", 0, "", fmt, ap);
   va_end(ap);
}

int ast_register_verbose(void (*v)(const char *string)) 
{
   struct verb *verb;

   if (!(verb = ast_malloc(sizeof(*verb))))
      return -1;

   verb->verboser = v;

   AST_RWLIST_WRLOCK(&verbosers);
   AST_RWLIST_INSERT_HEAD(&verbosers, verb, list);
   AST_RWLIST_UNLOCK(&verbosers);
   
   return 0;
}

int ast_unregister_verbose(void (*v)(const char *string))
{
   struct verb *cur;

   AST_RWLIST_WRLOCK(&verbosers);
   AST_RWLIST_TRAVERSE_SAFE_BEGIN(&verbosers, cur, list) {
      if (cur->verboser == v) {
         AST_RWLIST_REMOVE_CURRENT(list);
         ast_free(cur);
         break;
      }
   }
   AST_RWLIST_TRAVERSE_SAFE_END;
   AST_RWLIST_UNLOCK(&verbosers);
   
   return cur ? 0 : -1;
}

static void update_logchannels(void)
{
   struct logchannel *cur;

   AST_RWLIST_WRLOCK(&logchannels);

   global_logmask = 0;

   AST_RWLIST_TRAVERSE(&logchannels, cur, list) {
      cur->logmask = make_components(cur->components, cur->lineno);
      global_logmask |= cur->logmask;
   }

   AST_RWLIST_UNLOCK(&logchannels);
}

int ast_logger_register_level(const char *name)
{
   unsigned int level;
   unsigned int available = 0;

   AST_RWLIST_WRLOCK(&logchannels);

   for (level = 0; level < ARRAY_LEN(levels); level++) {
      if ((level >= 16) && !available && !levels[level]) {
         available = level;
         continue;
      }

      if (levels[level] && !strcasecmp(levels[level], name)) {
         ast_log(LOG_WARNING,
            "Unable to register dynamic logger level '%s': a standard logger level uses that name.\n",
            name);
         AST_RWLIST_UNLOCK(&logchannels);

         return -1;
      }
   }

   if (!available) {
      ast_log(LOG_WARNING,
         "Unable to register dynamic logger level '%s'; maximum number of levels registered.\n",
         name);
      AST_RWLIST_UNLOCK(&logchannels);

      return -1;
   }

   levels[available] = ast_strdup(name);

   AST_RWLIST_UNLOCK(&logchannels);

   ast_debug(1, "Registered dynamic logger level '%s' with index %d.\n", name, available);

   update_logchannels();

   return available;
}

void ast_logger_unregister_level(const char *name)
{
   unsigned int found = 0;
   unsigned int x;

   AST_RWLIST_WRLOCK(&logchannels);

   for (x = 16; x < ARRAY_LEN(levels); x++) {
      if (!levels[x]) {
         continue;
      }

      if (strcasecmp(levels[x], name)) {
         continue;
      }

      found = 1;
      break;
   }

   if (found) {
      /* take this level out of the global_logmask, to ensure that no new log messages
       * will be queued for it
       */

      global_logmask &= ~(1 << x);

      ast_free(levels[x]);
      levels[x] = NULL;
      AST_RWLIST_UNLOCK(&logchannels);

      ast_debug(1, "Unregistered dynamic logger level '%s' with index %d.\n", name, x);

      update_logchannels();
   } else {
      AST_RWLIST_UNLOCK(&logchannels);
   }
}