cdr.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 Call Detail Record API
 *
 * \author Mark Spencer <markster@digium.com>
 *
 * \note Includes code and algorithms from the Zapata library.
 *
 * \note We do a lot of checking here in the CDR code to try to be sure we don't ever let a CDR slip
 * through our fingers somehow.  If someone allocates a CDR, it must be completely handled normally
 * or a WARNING shall be logged, so that we can best keep track of any escape condition where the CDR
 * isn't properly generated and posted.
 */


/*** MODULEINFO
   <support_level>core</support_level>
 ***/

#include "asterisk.h"

ASTERISK_FILE_VERSION(__FILE__, "$Revision: 371989 $")

#include <signal.h>

#include "asterisk/lock.h"
#include "asterisk/channel.h"
#include "asterisk/cdr.h"
#include "asterisk/callerid.h"
#include "asterisk/manager.h"
#include "asterisk/causes.h"
#include "asterisk/linkedlists.h"
#include "asterisk/utils.h"
#include "asterisk/sched.h"
#include "asterisk/config.h"
#include "asterisk/cli.h"
#include "asterisk/stringfields.h"
#include "asterisk/data.h"

/*** DOCUMENTATION
 ***/

/*! Default AMA flag for billing records (CDR's) */
int ast_default_amaflags = AST_CDR_DOCUMENTATION;
char ast_default_accountcode[AST_MAX_ACCOUNT_CODE];

struct ast_cdr_beitem {
   char name[20];
   char desc[80];
   ast_cdrbe be;
   AST_RWLIST_ENTRY(ast_cdr_beitem) list;
};

static AST_RWLIST_HEAD_STATIC(be_list, ast_cdr_beitem);

struct ast_cdr_batch_item {
   struct ast_cdr *cdr;
   struct ast_cdr_batch_item *next;
};

static struct ast_cdr_batch {
   int size;
   struct ast_cdr_batch_item *head;
   struct ast_cdr_batch_item *tail;
} *batch = NULL;


static int cdr_sequence =  0;

static int cdr_seq_inc(struct ast_cdr *cdr);

static struct ast_sched_context *sched;
static int cdr_sched = -1;
static pthread_t cdr_thread = AST_PTHREADT_NULL;

static int enabled;
static const int ENABLED_DEFAULT = 1;

static int batchmode;
static const int BATCHMODE_DEFAULT = 0;

static int unanswered;
static const int UNANSWERED_DEFAULT = 0;

static int congestion;
static const int CONGESTION_DEFAULT = 0;

static int batchsize;
static const int BATCH_SIZE_DEFAULT = 100;

static int batchtime;
static const int BATCH_TIME_DEFAULT = 300;

static int batchscheduleronly;
static const int BATCH_SCHEDULER_ONLY_DEFAULT = 0;

static int batchsafeshutdown;
static const int BATCH_SAFE_SHUTDOWN_DEFAULT = 1;

AST_MUTEX_DEFINE_STATIC(cdr_batch_lock);

/* these are used to wake up the CDR thread when there's work to do */
AST_MUTEX_DEFINE_STATIC(cdr_pending_lock);
static ast_cond_t cdr_pending_cond;

int check_cdr_enabled(void)
{
   return enabled;
}

/*!
 * \brief Register a CDR driver. Each registered CDR driver generates a CDR
 * \retval 0 on success.
 * \retval -1 on error
 */
int ast_cdr_register(const char *name, const char *desc, ast_cdrbe be)
{
   struct ast_cdr_beitem *i = NULL;

   if (!name)
      return -1;

   if (!be) {
      ast_log(LOG_WARNING, "CDR engine '%s' lacks backend\n", name);
      return -1;
   }

   AST_RWLIST_WRLOCK(&be_list);
   AST_RWLIST_TRAVERSE(&be_list, i, list) {
      if (!strcasecmp(name, i->name)) {
         ast_log(LOG_WARNING, "Already have a CDR backend called '%s'\n", name);
         AST_RWLIST_UNLOCK(&be_list);
         return -1;
      }
   }

   if (!(i = ast_calloc(1, sizeof(*i))))
      return -1;

   i->be = be;
   ast_copy_string(i->name, name, sizeof(i->name));
   ast_copy_string(i->desc, desc, sizeof(i->desc));

   AST_RWLIST_INSERT_HEAD(&be_list, i, list);
   AST_RWLIST_UNLOCK(&be_list);

   return 0;
}

/*! unregister a CDR driver */
void ast_cdr_unregister(const char *name)
{
   struct ast_cdr_beitem *i = NULL;

   AST_RWLIST_WRLOCK(&be_list);
   AST_RWLIST_TRAVERSE_SAFE_BEGIN(&be_list, i, list) {
      if (!strcasecmp(name, i->name)) {
         AST_RWLIST_REMOVE_CURRENT(list);
         break;
      }
   }
   AST_RWLIST_TRAVERSE_SAFE_END;
   AST_RWLIST_UNLOCK(&be_list);

   if (i) {
      ast_verb(2, "Unregistered '%s' CDR backend\n", name);
      ast_free(i);
   }
}

int ast_cdr_isset_unanswered(void)
{
   return unanswered;
}

int ast_cdr_isset_congestion(void)
{
   return congestion;
}

struct ast_cdr *ast_cdr_dup_unique(struct ast_cdr *cdr)
{
   struct ast_cdr *newcdr = ast_cdr_dup(cdr);
   if (!newcdr)
      return NULL;

   cdr_seq_inc(newcdr);
   return newcdr;
}

struct ast_cdr *ast_cdr_dup_unique_swap(struct ast_cdr *cdr)
{
   struct ast_cdr *newcdr = ast_cdr_dup(cdr);
   if (!newcdr)
      return NULL;

   cdr_seq_inc(cdr);
   return newcdr;
}

/*! Duplicate a CDR record
   \returns Pointer to new CDR record
*/
struct ast_cdr *ast_cdr_dup(struct ast_cdr *cdr)
{
   struct ast_cdr *newcdr;

   if (!cdr) /* don't die if we get a null cdr pointer */
      return NULL;
   newcdr = ast_cdr_alloc();
   if (!newcdr)
      return NULL;

   memcpy(newcdr, cdr, sizeof(*newcdr));
   /* The varshead is unusable, volatile even, after the memcpy so we take care of that here */
   memset(&newcdr->varshead, 0, sizeof(newcdr->varshead));
   ast_cdr_copy_vars(newcdr, cdr);
   newcdr->next = NULL;

   return newcdr;
}

static const char *ast_cdr_getvar_internal(struct ast_cdr *cdr, const char *name, int recur)
{
   if (ast_strlen_zero(name))
      return NULL;

   for (; cdr; cdr = recur ? cdr->next : NULL) {
      struct ast_var_t *variables;
      struct varshead *headp = &cdr->varshead;
      AST_LIST_TRAVERSE(headp, variables, entries) {
         if (!strcasecmp(name, ast_var_name(variables)))
            return ast_var_value(variables);
      }
   }

   return NULL;
}

static void cdr_get_tv(struct timeval when, const char *fmt, char *buf, int bufsize)
{
   if (fmt == NULL) {   /* raw mode */
      snprintf(buf, bufsize, "%ld.%06ld", (long)when.tv_sec, (long)when.tv_usec);
   } else {
      if (when.tv_sec) {
         struct ast_tm tm;

         ast_localtime(&when, &tm, NULL);
         ast_strftime(buf, bufsize, fmt, &tm);
      }
   }
}

/*! CDR channel variable retrieval */
void ast_cdr_getvar(struct ast_cdr *cdr, const char *name, char **ret, char *workspace, int workspacelen, int recur, int raw)
{
   const char *fmt = "%Y-%m-%d %T";
   const char *varbuf;

   if (!cdr)  /* don't die if the cdr is null */
      return;

   *ret = NULL;
   /* special vars (the ones from the struct ast_cdr when requested by name)
      I'd almost say we should convert all the stringed vals to vars */

   if (!strcasecmp(name, "clid"))
      ast_copy_string(workspace, cdr->clid, workspacelen);
   else if (!strcasecmp(name, "src"))
      ast_copy_string(workspace, cdr->src, workspacelen);
   else if (!strcasecmp(name, "dst"))
      ast_copy_string(workspace, cdr->dst, workspacelen);
   else if (!strcasecmp(name, "dcontext"))
      ast_copy_string(workspace, cdr->dcontext, workspacelen);
   else if (!strcasecmp(name, "channel"))
      ast_copy_string(workspace, cdr->channel, workspacelen);
   else if (!strcasecmp(name, "dstchannel"))
      ast_copy_string(workspace, cdr->dstchannel, workspacelen);
   else if (!strcasecmp(name, "lastapp"))
      ast_copy_string(workspace, cdr->lastapp, workspacelen);
   else if (!strcasecmp(name, "lastdata"))
      ast_copy_string(workspace, cdr->lastdata, workspacelen);
   else if (!strcasecmp(name, "start"))
      cdr_get_tv(cdr->start, raw ? NULL : fmt, workspace, workspacelen);
   else if (!strcasecmp(name, "answer"))
      cdr_get_tv(cdr->answer, raw ? NULL : fmt, workspace, workspacelen);
   else if (!strcasecmp(name, "end"))
      cdr_get_tv(cdr->end, raw ? NULL : fmt, workspace, workspacelen);
   else if (!strcasecmp(name, "duration")) {
      snprintf(workspace, workspacelen, "%ld", cdr->end.tv_sec != 0 ? cdr->duration : (long)ast_tvdiff_ms(ast_tvnow(), cdr->start) / 1000);
   } else if (!strcasecmp(name, "billsec"))
      snprintf(workspace, workspacelen, "%ld", cdr->billsec || cdr->answer.tv_sec == 0 ? cdr->billsec : (long)ast_tvdiff_ms(ast_tvnow(), cdr->answer) / 1000);
   else if (!strcasecmp(name, "disposition")) {
      if (raw) {
         snprintf(workspace, workspacelen, "%ld", cdr->disposition);
      } else {
         ast_copy_string(workspace, ast_cdr_disp2str(cdr->disposition), workspacelen);
      }
   } else if (!strcasecmp(name, "amaflags")) {
      if (raw) {
         snprintf(workspace, workspacelen, "%ld", cdr->amaflags);
      } else {
         ast_copy_string(workspace, ast_cdr_flags2str(cdr->amaflags), workspacelen);
      }
   } else if (!strcasecmp(name, "accountcode"))
      ast_copy_string(workspace, cdr->accountcode, workspacelen);
   else if (!strcasecmp(name, "peeraccount"))
      ast_copy_string(workspace, cdr->peeraccount, workspacelen);
   else if (!strcasecmp(name, "uniqueid"))
      ast_copy_string(workspace, cdr->uniqueid, workspacelen);
   else if (!strcasecmp(name, "linkedid"))
      ast_copy_string(workspace, cdr->linkedid, workspacelen);
   else if (!strcasecmp(name, "userfield"))
      ast_copy_string(workspace, cdr->userfield, workspacelen);
   else if (!strcasecmp(name, "sequence"))
      snprintf(workspace, workspacelen, "%d", cdr->sequence);
   else if ((varbuf = ast_cdr_getvar_internal(cdr, name, recur)))
      ast_copy_string(workspace, varbuf, workspacelen);
   else
      workspace[0] = '\0';

   if (!ast_strlen_zero(workspace))
      *ret = workspace;
}

/* readonly cdr variables */
static const char * const cdr_readonly_vars[] = { "clid", "src", "dst", "dcontext", "channel", "dstchannel",
                    "lastapp", "lastdata", "start", "answer", "end", "duration",
                    "billsec", "disposition", "amaflags", "accountcode", "uniqueid", "linkedid",
                    "userfield", "sequence", NULL };
/*! Set a CDR channel variable
   \note You can't set the CDR variables that belong to the actual CDR record, like "billsec".
*/
int ast_cdr_setvar(struct ast_cdr *cdr, const char *name, const char *value, int recur)
{
   struct ast_var_t *newvariable;
   struct varshead *headp;
   int x;

   for (x = 0; cdr_readonly_vars[x]; x++) {
      if (!strcasecmp(name, cdr_readonly_vars[x])) {
         ast_log(LOG_ERROR, "Attempt to set the '%s' read-only variable!.\n", name);
         return -1;
      }
   }

   if (!cdr) {
      ast_log(LOG_ERROR, "Attempt to set a variable on a nonexistent CDR record.\n");
      return -1;
   }

   for (; cdr; cdr = recur ? cdr->next : NULL) {
      if (ast_test_flag(cdr, AST_CDR_FLAG_DONT_TOUCH) && ast_test_flag(cdr, AST_CDR_FLAG_LOCKED))
         continue;
      headp = &cdr->varshead;
      AST_LIST_TRAVERSE_SAFE_BEGIN(headp, newvariable, entries) {
         if (!strcasecmp(ast_var_name(newvariable), name)) {
            /* there is already such a variable, delete it */
            AST_LIST_REMOVE_CURRENT(entries);
            ast_var_delete(newvariable);
            break;
         }
      }
      AST_LIST_TRAVERSE_SAFE_END;

      if (value) {
         newvariable = ast_var_assign(name, value);
         AST_LIST_INSERT_HEAD(headp, newvariable, entries);
      }
   }

   return 0;
}

int ast_cdr_copy_vars(struct ast_cdr *to_cdr, struct ast_cdr *from_cdr)
{
   struct ast_var_t *variables, *newvariable = NULL;
   struct varshead *headpa, *headpb;
   const char *var, *val;
   int x = 0;

   if (!to_cdr || !from_cdr) /* don't die if one of the pointers is null */
      return 0;

   headpa = &from_cdr->varshead;
   headpb = &to_cdr->varshead;

   AST_LIST_TRAVERSE(headpa,variables,entries) {
      if (variables &&
          (var = ast_var_name(variables)) && (val = ast_var_value(variables)) &&
          !ast_strlen_zero(var) && !ast_strlen_zero(val)) {
         newvariable = ast_var_assign(var, val);
         AST_LIST_INSERT_HEAD(headpb, newvariable, entries);
         x++;
      }
   }

   return x;
}

int ast_cdr_serialize_variables(struct ast_cdr *cdr, struct ast_str **buf, char delim, char sep, int recur)
{
   struct ast_var_t *variables;
   const char *var;
   char *tmp;
   char workspace[256];
   int total = 0, x = 0, i;

   ast_str_reset(*buf);

   for (; cdr; cdr = recur ? cdr->next : NULL) {
      if (++x > 1)
         ast_str_append(buf, 0, "\n");

      AST_LIST_TRAVERSE(&cdr->varshead, variables, entries) {
         if (!(var = ast_var_name(variables))) {
            continue;
         }

         if (ast_str_append(buf, 0, "level %d: %s%c%s%c", x, var, delim, S_OR(ast_var_value(variables), ""), sep) < 0) {
            ast_log(LOG_ERROR, "Data Buffer Size Exceeded!\n");
            break;
         }

         total++;
      }

      for (i = 0; cdr_readonly_vars[i]; i++) {
         workspace[0] = 0; /* null out the workspace, because the cdr_get_tv() won't write anything if time is NULL, so you get old vals */
         ast_cdr_getvar(cdr, cdr_readonly_vars[i], &tmp, workspace, sizeof(workspace), 0, 0);
         if (!tmp)
            continue;

         if (ast_str_append(buf, 0, "level %d: %s%c%s%c", x, cdr_readonly_vars[i], delim, tmp, sep) < 0) {
            ast_log(LOG_ERROR, "Data Buffer Size Exceeded!\n");
            break;
         } else
            total++;
      }
   }

   return total;
}


void ast_cdr_free_vars(struct ast_cdr *cdr, int recur)
{

   /* clear variables */
   for (; cdr; cdr = recur ? cdr->next : NULL) {
      struct ast_var_t *vardata;
      struct varshead *headp = &cdr->varshead;
      while ((vardata = AST_LIST_REMOVE_HEAD(headp, entries)))
         ast_var_delete(vardata);
   }
}

/*! \brief  print a warning if cdr already posted */
static void check_post(struct ast_cdr *cdr)
{
   if (!cdr)
      return;
   if (ast_test_flag(cdr, AST_CDR_FLAG_POSTED))
      ast_log(LOG_NOTICE, "CDR on channel '%s' already posted\n", S_OR(cdr->channel, "<unknown>"));
}

void ast_cdr_free(struct ast_cdr *cdr)
{

   while (cdr) {
      struct ast_cdr *next = cdr->next;

      ast_cdr_free_vars(cdr, 0);
      ast_free(cdr);
      cdr = next;
   }
}

/*! \brief the same as a cdr_free call, only with no checks; just get rid of it */
void ast_cdr_discard(struct ast_cdr *cdr)
{
   while (cdr) {
      struct ast_cdr *next = cdr->next;

      ast_cdr_free_vars(cdr, 0);
      ast_free(cdr);
      cdr = next;
   }
}

struct ast_cdr *ast_cdr_alloc(void)
{
   struct ast_cdr *x;
   x = ast_calloc(1, sizeof(*x));
   if (!x)
      ast_log(LOG_ERROR,"Allocation Failure for a CDR!\n");
   return x;
}

static void cdr_merge_vars(struct ast_cdr *to, struct ast_cdr *from)
{
   struct ast_var_t *variablesfrom,*variablesto;
   struct varshead *headpfrom = &to->varshead;
   struct varshead *headpto = &from->varshead;
   AST_LIST_TRAVERSE_SAFE_BEGIN(headpfrom, variablesfrom, entries) {
      /* for every var in from, stick it in to */
      const char *fromvarname, *fromvarval;
      const char *tovarname = NULL, *tovarval = NULL;
      fromvarname = ast_var_name(variablesfrom);
      fromvarval = ast_var_value(variablesfrom);
      tovarname = 0;

      /* now, quick see if that var is in the 'to' cdr already */
      AST_LIST_TRAVERSE(headpto, variablesto, entries) {

         /* now, quick see if that var is in the 'to' cdr already */
         if ( strcasecmp(fromvarname, ast_var_name(variablesto)) == 0 ) {
            tovarname = ast_var_name(variablesto);
            tovarval = ast_var_value(variablesto);
            break;
         }
      }
      if (tovarname && strcasecmp(fromvarval,tovarval) != 0) {  /* this message here to see how irritating the userbase finds it */
         ast_log(LOG_NOTICE, "Merging CDR's: variable %s value %s dropped in favor of value %s\n", tovarname, fromvarval, tovarval);
         continue;
      } else if (tovarname && strcasecmp(fromvarval,tovarval) == 0) /* if they are the same, the job is done */
         continue;

      /* rip this var out of the from cdr, and stick it in the to cdr */
      AST_LIST_MOVE_CURRENT(headpto, entries);
   }
   AST_LIST_TRAVERSE_SAFE_END;
}

void ast_cdr_merge(struct ast_cdr *to, struct ast_cdr *from)
{
   struct ast_cdr *zcdr;
   struct ast_cdr *lto = NULL;
   struct ast_cdr *lfrom = NULL;
   int discard_from = 0;

   if (!to || !from)
      return;

   /* don't merge into locked CDR's -- it's bad business */
   if (ast_test_flag(to, AST_CDR_FLAG_LOCKED)) {
      zcdr = to; /* safety valve? */
      while (to->next) {
         lto = to;
         to = to->next;
      }

      if (ast_test_flag(to, AST_CDR_FLAG_LOCKED)) {
         ast_log(LOG_WARNING, "Merging into locked CDR... no choice.\n");
         to = zcdr; /* safety-- if all there are is locked CDR's, then.... ?? */
         lto = NULL;
      }
   }

   if (ast_test_flag(from, AST_CDR_FLAG_LOCKED)) {
      struct ast_cdr *llfrom = NULL;
      discard_from = 1;
      if (lto) {
         /* insert the from stuff after lto */
         lto->next = from;
         lfrom = from;
         while (lfrom && lfrom->next) {
            if (!lfrom->next->next)
               llfrom = lfrom;
            lfrom = lfrom->next;
         }
         /* rip off the last entry and put a copy of the to at the end */
         if (llfrom) {
            llfrom->next = to;
         }
         from = lfrom;
      } else {
         /* save copy of the current *to cdr */
         struct ast_cdr tcdr;
         memcpy(&tcdr, to, sizeof(tcdr));
         /* copy in the locked from cdr */
         memcpy(to, from, sizeof(*to));
         lfrom = from;
         while (lfrom && lfrom->next) {
            if (!lfrom->next->next)
               llfrom = lfrom;
            lfrom = lfrom->next;
         }
         from->next = NULL;
         /* rip off the last entry and put a copy of the to at the end */
         if (llfrom == from) {
            to = to->next = ast_cdr_dup(&tcdr);
         } else if (llfrom) {
            to = llfrom->next = ast_cdr_dup(&tcdr);
         }
         from = lfrom;
      }
   }

   if (!ast_tvzero(from->start)) {
      if (!ast_tvzero(to->start)) {
         if (ast_tvcmp(to->start, from->start) > 0 ) {
            to->start = from->start; /* use the earliest time */
            from->start = ast_tv(0,0); /* we actively "steal" these values */
         }
         /* else nothing to do */
      } else {
         to->start = from->start;
         from->start = ast_tv(0,0); /* we actively "steal" these values */
      }
   }
   if (!ast_tvzero(from->answer)) {
      if (!ast_tvzero(to->answer)) {
         if (ast_tvcmp(to->answer, from->answer) > 0 ) {
            to->answer = from->answer; /* use the earliest time */
            from->answer = ast_tv(0,0); /* we actively "steal" these values */
         }
         /* we got the earliest answer time, so we'll settle for that? */
      } else {
         to->answer = from->answer;
         from->answer = ast_tv(0,0); /* we actively "steal" these values */
      }
   }
   if (!ast_tvzero(from->end)) {
      if (!ast_tvzero(to->end)) {
         if (ast_tvcmp(to->end, from->end) < 0 ) {
            to->end = from->end; /* use the latest time */
            from->end = ast_tv(0,0); /* we actively "steal" these values */
            to->duration = to->end.tv_sec - to->start.tv_sec;  /* don't forget to update the duration, billsec, when we set end */
            to->billsec = ast_tvzero(to->answer) ? 0 : to->end.tv_sec - to->answer.tv_sec;
         }
         /* else, nothing to do */
      } else {
         to->end = from->end;
         from->end = ast_tv(0,0); /* we actively "steal" these values */
         to->duration = to->end.tv_sec - to->start.tv_sec;
         to->billsec = ast_tvzero(to->answer) ? 0 : to->end.tv_sec - to->answer.tv_sec;
      }
   }
   if (to->disposition < from->disposition) {
      to->disposition = from->disposition;
      from->disposition = AST_CDR_NOANSWER;
   }
   if (ast_strlen_zero(to->lastapp) && !ast_strlen_zero(from->lastapp)) {
      ast_copy_string(to->lastapp, from->lastapp, sizeof(to->lastapp));
      from->lastapp[0] = 0; /* theft */
   }
   if (ast_strlen_zero(to->lastdata) && !ast_strlen_zero(from->lastdata)) {
      ast_copy_string(to->lastdata, from->lastdata, sizeof(to->lastdata));
      from->lastdata[0] = 0; /* theft */
   }
   if (ast_strlen_zero(to->dcontext) && !ast_strlen_zero(from->dcontext)) {
      ast_copy_string(to->dcontext, from->dcontext, sizeof(to->dcontext));
      from->dcontext[0] = 0; /* theft */
   }
   if (ast_strlen_zero(to->dstchannel) && !ast_strlen_zero(from->dstchannel)) {
      ast_copy_string(to->dstchannel, from->dstchannel, sizeof(to->dstchannel));
      from->dstchannel[0] = 0; /* theft */
   }
   if (!ast_strlen_zero(from->channel) && (ast_strlen_zero(to->channel) || !strncasecmp(from->channel, "Agent/", 6))) {
      ast_copy_string(to->channel, from->channel, sizeof(to->channel));
      from->channel[0] = 0; /* theft */
   }
   if (ast_strlen_zero(to->src) && !ast_strlen_zero(from->src)) {
      ast_copy_string(to->src, from->src, sizeof(to->src));
      from->src[0] = 0; /* theft */
   }
   if (ast_strlen_zero(to->clid) && !ast_strlen_zero(from->clid)) {
      ast_copy_string(to->clid, from->clid, sizeof(to->clid));
      from->clid[0] = 0; /* theft */
   }
   if (ast_strlen_zero(to->dst) && !ast_strlen_zero(from->dst)) {
      ast_copy_string(to->dst, from->dst, sizeof(to->dst));
      from->dst[0] = 0; /* theft */
   }
   if (!to->amaflags)
      to->amaflags = AST_CDR_DOCUMENTATION;
   if (!from->amaflags)
      from->amaflags = AST_CDR_DOCUMENTATION; /* make sure both amaflags are set to something (DOC is default) */
   if (ast_test_flag(from, AST_CDR_FLAG_LOCKED) || (to->amaflags == AST_CDR_DOCUMENTATION && from->amaflags != AST_CDR_DOCUMENTATION)) {
      to->amaflags = from->amaflags;
   }
   if (ast_test_flag(from, AST_CDR_FLAG_LOCKED) || (ast_strlen_zero(to->accountcode) && !ast_strlen_zero(from->accountcode))) {
      ast_copy_string(to->accountcode, from->accountcode, sizeof(to->accountcode));
   }
   if (ast_test_flag(from, AST_CDR_FLAG_LOCKED) || (ast_strlen_zero(to->peeraccount) && !ast_strlen_zero(from->peeraccount))) {
      ast_copy_string(to->peeraccount, from->peeraccount, sizeof(to->peeraccount));
   }
   if (ast_test_flag(from, AST_CDR_FLAG_LOCKED) || (ast_strlen_zero(to->userfield) && !ast_strlen_zero(from->userfield))) {
      ast_copy_string(to->userfield, from->userfield, sizeof(to->userfield));
   }
   /* flags, varsead, ? */
   cdr_merge_vars(from, to);

   if (ast_test_flag(from, AST_CDR_FLAG_KEEP_VARS))
      ast_set_flag(to, AST_CDR_FLAG_KEEP_VARS);
   if (ast_test_flag(from, AST_CDR_FLAG_POSTED))
      ast_set_flag(to, AST_CDR_FLAG_POSTED);
   if (ast_test_flag(from, AST_CDR_FLAG_LOCKED))
      ast_set_flag(to, AST_CDR_FLAG_LOCKED);
   if (ast_test_flag(from, AST_CDR_FLAG_CHILD))
      ast_set_flag(to, AST_CDR_FLAG_CHILD);
   if (ast_test_flag(from, AST_CDR_FLAG_POST_DISABLED))
      ast_set_flag(to, AST_CDR_FLAG_POST_DISABLED);

   /* last, but not least, we need to merge any forked CDRs to the 'to' cdr */
   while (from->next) {
      /* just rip 'em off the 'from' and insert them on the 'to' */
      zcdr = from->next;
      from->next = zcdr->next;
      zcdr->next = NULL;
      /* zcdr is now ripped from the current list; */
      ast_cdr_append(to, zcdr);
   }
   if (discard_from)
      ast_cdr_discard(from);
}

void ast_cdr_start(struct ast_cdr *cdr)
{
   for (; cdr; cdr = cdr->next) {
      if (!ast_test_flag(cdr, AST_CDR_FLAG_LOCKED)) {
         check_post(cdr);
         cdr->start = ast_tvnow();
      }
   }
}

void ast_cdr_answer(struct ast_cdr *cdr)
{

   for (; cdr; cdr = cdr->next) {
      if (ast_test_flag(cdr, AST_CDR_FLAG_ANSLOCKED))
         continue;
      if (ast_test_flag(cdr, AST_CDR_FLAG_DONT_TOUCH) && ast_test_flag(cdr, AST_CDR_FLAG_LOCKED))
         continue;
      check_post(cdr);
      if (cdr->disposition < AST_CDR_ANSWERED)
         cdr->disposition = AST_CDR_ANSWERED;
      if (ast_tvzero(cdr->answer))
         cdr->answer = ast_tvnow();
   }
}

void ast_cdr_busy(struct ast_cdr *cdr)
{

   for (; cdr; cdr = cdr->next) {
      if (!ast_test_flag(cdr, AST_CDR_FLAG_LOCKED)) {
         check_post(cdr);
         cdr->disposition = AST_CDR_BUSY;
      }
   }
}

void ast_cdr_failed(struct ast_cdr *cdr)
{
   for (; cdr; cdr = cdr->next) {
      check_post(cdr);
      if (!ast_test_flag(cdr, AST_CDR_FLAG_LOCKED)) {
         check_post(cdr);
         if (cdr->disposition < AST_CDR_FAILED)
            cdr->disposition = AST_CDR_FAILED;
      }
   }
}

void ast_cdr_noanswer(struct ast_cdr *cdr)
{
   while (cdr) {
      if (!ast_test_flag(cdr, AST_CDR_FLAG_LOCKED)) {
         check_post(cdr);
         cdr->disposition = AST_CDR_NOANSWER;
      }
      cdr = cdr->next;
   }
}

void ast_cdr_congestion(struct ast_cdr *cdr)
{
   char *chan;

   /* if congestion log is disabled, pass the buck to ast_cdr_failed */
   if (!congestion) {
      ast_cdr_failed(cdr);
   }

   while (cdr && congestion) {
      if (!ast_test_flag(cdr, AST_CDR_FLAG_LOCKED)) {
         chan = !ast_strlen_zero(cdr->channel) ? cdr->channel : "<unknown>";

         if (ast_test_flag(cdr, AST_CDR_FLAG_POSTED)) {
            ast_log(LOG_WARNING, "CDR on channel '%s' already posted\n", chan);
         }

         if (cdr->disposition < AST_CDR_CONGESTION) {
            cdr->disposition = AST_CDR_CONGESTION;
         }
      }
      cdr = cdr->next;
   }
}

/* everywhere ast_cdr_disposition is called, it will call ast_cdr_failed()
   if ast_cdr_disposition returns a non-zero value */

int ast_cdr_disposition(struct ast_cdr *cdr, int cause)
{
   int res = 0;

   for (; cdr; cdr = cdr->next) {
      switch (cause) {  /* handle all the non failure, busy cases, return 0 not to set disposition,
                     return -1 to set disposition to FAILED */
      case AST_CAUSE_BUSY:
         ast_cdr_busy(cdr);
         break;
      case AST_CAUSE_NO_ANSWER:
         ast_cdr_noanswer(cdr);
         break;
      case AST_CAUSE_NORMAL_CIRCUIT_CONGESTION:
         ast_cdr_congestion(cdr);
         break;
      case AST_CAUSE_NORMAL:
         break;
      default:
         res = -1;
      }
   }
   return res;
}

void ast_cdr_setdestchan(struct ast_cdr *cdr, const char *chann)
{
   for (; cdr; cdr = cdr->next) {
      if (!ast_test_flag(cdr, AST_CDR_FLAG_LOCKED)) {
         check_post(cdr);
         ast_copy_string(cdr->dstchannel, chann, sizeof(cdr->dstchannel));
      }
   }
}

void ast_cdr_setapp(struct ast_cdr *cdr, const char *app, const char *data)
{

   for (; cdr; cdr = cdr->next) {
      if (!ast_test_flag(cdr, AST_CDR_FLAG_LOCKED)) {
         check_post(cdr);
         ast_copy_string(cdr->lastapp, S_OR(app, ""), sizeof(cdr->lastapp));
         ast_copy_string(cdr->lastdata, S_OR(data, ""), sizeof(cdr->lastdata));
      }
   }
}

void ast_cdr_setanswer(struct ast_cdr *cdr, struct timeval t)
{

   for (; cdr; cdr = cdr->next) {
      if (ast_test_flag(cdr, AST_CDR_FLAG_ANSLOCKED))
         continue;
      if (ast_test_flag(cdr, AST_CDR_FLAG_DONT_TOUCH) && ast_test_flag(cdr, AST_CDR_FLAG_LOCKED))
         continue;
      check_post(cdr);
      cdr->answer = t;
   }
}

void ast_cdr_setdisposition(struct ast_cdr *cdr, long int disposition)
{

   for (; cdr; cdr = cdr->next) {
      if (ast_test_flag(cdr, AST_CDR_FLAG_LOCKED))
         continue;
      check_post(cdr);
      cdr->disposition = disposition;
   }
}

/* set cid info for one record */
static void set_one_cid(struct ast_cdr *cdr, struct ast_channel *c)
{
   const char *num;

   if (!cdr) {
      return;
   }

   /* Grab source from ANI or normal Caller*ID */
   num = S_COR(ast_channel_caller(c)->ani.number.valid, ast_channel_caller(c)->ani.number.str,
      S_COR(ast_channel_caller(c)->id.number.valid, ast_channel_caller(c)->id.number.str, NULL));
   ast_callerid_merge(cdr->clid, sizeof(cdr->clid),
      S_COR(ast_channel_caller(c)->id.name.valid, ast_channel_caller(c)->id.name.str, NULL), num, "");
   ast_copy_string(cdr->src, S_OR(num, ""), sizeof(cdr->src));
   ast_cdr_setvar(cdr, "dnid", S_OR(ast_channel_dialed(c)->number.str, ""), 0);

   if (ast_channel_caller(c)->id.subaddress.valid) {
      ast_cdr_setvar(cdr, "callingsubaddr", S_OR(ast_channel_caller(c)->id.subaddress.str, ""), 0);
   }
   if (ast_channel_dialed(c)->subaddress.valid) {
      ast_cdr_setvar(cdr, "calledsubaddr", S_OR(ast_channel_dialed(c)->subaddress.str, ""), 0);
   }
}

int ast_cdr_setcid(struct ast_cdr *cdr, struct ast_channel *c)
{
   for (; cdr; cdr = cdr->next) {
      if (!ast_test_flag(cdr, AST_CDR_FLAG_LOCKED))
         set_one_cid(cdr, c);
   }
   return 0;
}

static int cdr_seq_inc(struct ast_cdr *cdr)
{
   return (cdr->sequence = ast_atomic_fetchadd_int(&cdr_sequence, +1));
}

int ast_cdr_init(struct ast_cdr *cdr, struct ast_channel *c)
{
   for ( ; cdr ; cdr = cdr->next) {
      if (!ast_test_flag(cdr, AST_CDR_FLAG_LOCKED)) {
         ast_copy_string(cdr->channel, ast_channel_name(c), sizeof(cdr->channel));
         set_one_cid(cdr, c);
         cdr_seq_inc(cdr);

         cdr->disposition = (ast_channel_state(c) == AST_STATE_UP) ?  AST_CDR_ANSWERED : AST_CDR_NOANSWER;
         cdr->amaflags = ast_channel_amaflags(c) ? ast_channel_amaflags(c) :  ast_default_amaflags;
         ast_copy_string(cdr->accountcode, ast_channel_accountcode(c), sizeof(cdr->accountcode));
         ast_copy_string(cdr->peeraccount, ast_channel_peeraccount(c), sizeof(cdr->peeraccount));
         /* Destination information */
         ast_copy_string(cdr->dst, S_OR(ast_channel_macroexten(c),ast_channel_exten(c)), sizeof(cdr->dst));
         ast_copy_string(cdr->dcontext, S_OR(ast_channel_macrocontext(c),ast_channel_context(c)), sizeof(cdr->dcontext));
         /* Unique call identifier */
         ast_copy_string(cdr->uniqueid, ast_channel_uniqueid(c), sizeof(cdr->uniqueid));
         /* Linked call identifier */
         ast_copy_string(cdr->linkedid, ast_channel_linkedid(c), sizeof(cdr->linkedid));
      }
   }
   return 0;
}

/* Three routines were "fixed" via 10668, and later shown that
   users were depending on this behavior. ast_cdr_end,
   ast_cdr_setvar and ast_cdr_answer are the three routines.
   While most of the other routines would not touch
   LOCKED cdr's, these three routines were designed to
   operate on locked CDR's as a matter of course.
   I now appreciate how this plays with the ForkCDR app,
   which forms these cdr chains in the first place.
   cdr_end is pretty key: all cdrs created are closed
   together. They only vary by start time. Arithmetically,
   users can calculate the subintervals they wish to track. */

void ast_cdr_end(struct ast_cdr *cdr)
{
   for ( ; cdr ; cdr = cdr->next) {
      if (ast_test_flag(cdr, AST_CDR_FLAG_DONT_TOUCH) && ast_test_flag(cdr, AST_CDR_FLAG_LOCKED))
         continue;
      check_post(cdr);
      if (ast_tvzero(cdr->end))
         cdr->end = ast_tvnow();
      if (ast_tvzero(cdr->start)) {
         ast_log(LOG_WARNING, "CDR on channel '%s' has not started\n", S_OR(cdr->channel, "<unknown>"));
         cdr->disposition = AST_CDR_FAILED;
      } else
         cdr->duration = cdr->end.tv_sec - cdr->start.tv_sec;
      if (ast_tvzero(cdr->answer)) {
         if (cdr->disposition == AST_CDR_ANSWERED) {
            ast_log(LOG_WARNING, "CDR on channel '%s' has no answer time but is 'ANSWERED'\n", S_OR(cdr->channel, "<unknown>"));
            cdr->disposition = AST_CDR_FAILED;
         }
      } else {
         cdr->billsec = cdr->end.tv_sec - cdr->answer.tv_sec;
         if (ast_test_flag(&ast_options, AST_OPT_FLAG_INITIATED_SECONDS))
            cdr->billsec += cdr->end.tv_usec > cdr->answer.tv_usec ? 1 : 0;
      }
   }
}

char *ast_cdr_disp2str(int disposition)
{
   switch (disposition) {
   case AST_CDR_NULL:
      return "NO ANSWER"; /* by default, for backward compatibility */
   case AST_CDR_NOANSWER:
      return "NO ANSWER";
   case AST_CDR_FAILED:
      return "FAILED";
   case AST_CDR_BUSY:
      return "BUSY";
   case AST_CDR_ANSWERED:
      return "ANSWERED";
   case AST_CDR_CONGESTION:
      return "CONGESTION";
   }
   return "UNKNOWN";
}

/*! Converts AMA flag to printable string 
 *
 * \param flag, flags
 */
char *ast_cdr_flags2str(int flag)
{
   switch (flag) {
   case AST_CDR_OMIT:
      return "OMIT";
   case AST_CDR_BILLING:
      return "BILLING";
   case AST_CDR_DOCUMENTATION:
      return "DOCUMENTATION";
   }
   return "Unknown";
}

int ast_cdr_setaccount(struct ast_channel *chan, const char *account)
{
   struct ast_cdr *cdr = ast_channel_cdr(chan);
   const char *old_acct = "";

   if (!ast_strlen_zero(ast_channel_accountcode(chan))) {
      old_acct = ast_strdupa(ast_channel_accountcode(chan));
   }

   ast_channel_accountcode_set(chan, account);
   for ( ; cdr ; cdr = cdr->next) {
      if (!ast_test_flag(cdr, AST_CDR_FLAG_LOCKED)) {
         ast_copy_string(cdr->accountcode, ast_channel_accountcode(chan), sizeof(cdr->accountcode));
      }
   }
   /*** DOCUMENTATION
      <managerEventInstance>
         <synopsis>Raised when a CDR's AccountCode is changed.</synopsis>
      </managerEventInstance>
   ***/
   ast_manager_event(chan, EVENT_FLAG_CALL, "NewAccountCode",
         "Channel: %s\r\n"
         "Uniqueid: %s\r\n"
         "AccountCode: %s\r\n"
         "OldAccountCode: %s\r\n",
         ast_channel_name(chan), ast_channel_uniqueid(chan), ast_channel_accountcode(chan), old_acct);

   return 0;
}

int ast_cdr_setpeeraccount(struct ast_channel *chan, const char *account)
{
   struct ast_cdr *cdr = ast_channel_cdr(chan);
   const char *old_acct = "";

   if (!ast_strlen_zero(ast_channel_peeraccount(chan))) {
      old_acct = ast_strdupa(ast_channel_peeraccount(chan));
   }

   ast_channel_peeraccount_set(chan, account);
   for ( ; cdr ; cdr = cdr->next) {
      if (!ast_test_flag(cdr, AST_CDR_FLAG_LOCKED)) {
         ast_copy_string(cdr->peeraccount, ast_channel_peeraccount(chan), sizeof(cdr->peeraccount));
      }
   }
   /*** DOCUMENTATION
      <managerEventInstance>
         <synopsis>Raised when a CDR's PeerAccount is changed.</synopsis>
      </managerEventInstance>
   ***/
   ast_manager_event(chan, EVENT_FLAG_CALL, "NewPeerAccount",
         "Channel: %s\r\n"
         "Uniqueid: %s\r\n"
         "PeerAccount: %s\r\n"
         "OldPeerAccount: %s\r\n",
         ast_channel_name(chan), ast_channel_uniqueid(chan), ast_channel_peeraccount(chan), old_acct);

   return 0;
}

int ast_cdr_setamaflags(struct ast_channel *chan, const char *flag)
{
   struct ast_cdr *cdr;
   int newflag = ast_cdr_amaflags2int(flag);
   if (newflag) {
      for (cdr = ast_channel_cdr(chan); cdr; cdr = cdr->next) {
         if (!ast_test_flag(cdr, AST_CDR_FLAG_LOCKED)) {
            cdr->amaflags = newflag;
         }
      }
   }

   return 0;
}

int ast_cdr_setuserfield(struct ast_channel *chan, const char *userfield)
{
   struct ast_cdr *cdr = ast_channel_cdr(chan);

   for ( ; cdr ; cdr = cdr->next) {
      if (!ast_test_flag(cdr, AST_CDR_FLAG_LOCKED))
         ast_copy_string(cdr->userfield, userfield, sizeof(cdr->userfield));
   }

   return 0;
}

int ast_cdr_appenduserfield(struct ast_channel *chan, const char *userfield)
{
   struct ast_cdr *cdr = ast_channel_cdr(chan);

   for ( ; cdr ; cdr = cdr->next) {
      int len = strlen(cdr->userfield);

      if (!ast_test_flag(cdr, AST_CDR_FLAG_LOCKED))
         ast_copy_string(cdr->userfield + len, userfield, sizeof(cdr->userfield) - len);
   }

   return 0;
}

int ast_cdr_update(struct ast_channel *c)
{
   struct ast_cdr *cdr = ast_channel_cdr(c);

   for ( ; cdr ; cdr = cdr->next) {
      if (!ast_test_flag(cdr, AST_CDR_FLAG_LOCKED)) {
         set_one_cid(cdr, c);

         /* Copy account code et-al */
         ast_copy_string(cdr->accountcode, ast_channel_accountcode(c), sizeof(cdr->accountcode));
         ast_copy_string(cdr->peeraccount, ast_channel_peeraccount(c), sizeof(cdr->peeraccount));
         ast_copy_string(cdr->linkedid, ast_channel_linkedid(c), sizeof(cdr->linkedid));

         /* Destination information */ /* XXX privilege macro* ? */
         ast_copy_string(cdr->dst, S_OR(ast_channel_macroexten(c), ast_channel_exten(c)), sizeof(cdr->dst));
         ast_copy_string(cdr->dcontext, S_OR(ast_channel_macrocontext(c), ast_channel_context(c)), sizeof(cdr->dcontext));
      }
   }

   return 0;
}

int ast_cdr_amaflags2int(const char *flag)
{
   if (!strcasecmp(flag, "default"))
      return 0;
   if (!strcasecmp(flag, "omit"))
      return AST_CDR_OMIT;
   if (!strcasecmp(flag, "billing"))
      return AST_CDR_BILLING;
   if (!strcasecmp(flag, "documentation"))
      return AST_CDR_DOCUMENTATION;
   return -1;
}

static void post_cdr(struct ast_cdr *cdr)
{
   struct ast_cdr_beitem *i;

   for ( ; cdr ; cdr = cdr->next) {
      if (!unanswered && cdr->disposition < AST_CDR_ANSWERED && (ast_strlen_zero(cdr->channel) || ast_strlen_zero(cdr->dstchannel))) {
         /* For people, who don't want to see unanswered single-channel events */
         ast_set_flag(cdr, AST_CDR_FLAG_POST_DISABLED);
         continue;
      }

      /* don't post CDRs that are for dialed channels unless those
       * channels were originated from asterisk (pbx_spool, manager,
       * cli) */
      if (ast_test_flag(cdr, AST_CDR_FLAG_DIALED) && !ast_test_flag(cdr, AST_CDR_FLAG_ORIGINATED)) {
         ast_set_flag(cdr, AST_CDR_FLAG_POST_DISABLED);
         continue;
      }

      check_post(cdr);
      ast_set_flag(cdr, AST_CDR_FLAG_POSTED);
      if (ast_test_flag(cdr, AST_CDR_FLAG_POST_DISABLED))
         continue;
      AST_RWLIST_RDLOCK(&be_list);
      AST_RWLIST_TRAVERSE(&be_list, i, list) {
         i->be(cdr);
      }
      AST_RWLIST_UNLOCK(&be_list);
   }
}

void ast_cdr_reset(struct ast_cdr *cdr, struct ast_flags *_flags)
{
   struct ast_cdr *duplicate;
   struct ast_flags flags = { 0 };

   if (_flags)
      ast_copy_flags(&flags, _flags, AST_FLAGS_ALL);

   for ( ; cdr ; cdr = cdr->next) {
      /* Detach if post is requested */
      if (ast_test_flag(&flags, AST_CDR_FLAG_LOCKED) || !ast_test_flag(cdr, AST_CDR_FLAG_LOCKED)) {
         if (ast_test_flag(&flags, AST_CDR_FLAG_POSTED)) {
            ast_cdr_end(cdr);
            if ((duplicate = ast_cdr_dup_unique_swap(cdr))) {
               ast_cdr_detach(duplicate);
            }
            ast_set_flag(cdr, AST_CDR_FLAG_POSTED);
         }

         /* enable CDR only */
         if (ast_test_flag(&flags, AST_CDR_FLAG_POST_ENABLE)) {
            ast_clear_flag(cdr, AST_CDR_FLAG_POST_DISABLED);
            continue;
         }

         /* clear variables */
         if (!ast_test_flag(&flags, AST_CDR_FLAG_KEEP_VARS)) {
            ast_cdr_free_vars(cdr, 0);
         }

         /* Reset to initial state */
         ast_clear_flag(cdr, AST_FLAGS_ALL);
         memset(&cdr->start, 0, sizeof(cdr->start));
         memset(&cdr->end, 0, sizeof(cdr->end));
         memset(&cdr->answer, 0, sizeof(cdr->answer));
         cdr->billsec = 0;
         cdr->duration = 0;
         ast_cdr_start(cdr);
         cdr->disposition = AST_CDR_NOANSWER;
      }
   }
}

void ast_cdr_specialized_reset(struct ast_cdr *cdr, struct ast_flags *_flags)
{
   struct ast_flags flags = { 0 };

   if (_flags)
      ast_copy_flags(&flags, _flags, AST_FLAGS_ALL);

   /* Reset to initial state */
   if (ast_test_flag(cdr, AST_CDR_FLAG_POST_DISABLED)) { /* But do NOT lose the NoCDR() setting */
      ast_clear_flag(cdr, AST_FLAGS_ALL);
      ast_set_flag(cdr, AST_CDR_FLAG_POST_DISABLED);
   } else {
      ast_clear_flag(cdr, AST_FLAGS_ALL);
   }

   memset(&cdr->start, 0, sizeof(cdr->start));
   memset(&cdr->end, 0, sizeof(cdr->end));
   memset(&cdr->answer, 0, sizeof(cdr->answer));
   cdr->billsec = 0;
   cdr->duration = 0;
   ast_cdr_start(cdr);
   cdr->disposition = AST_CDR_NULL;
}

struct ast_cdr *ast_cdr_append(struct ast_cdr *cdr, struct ast_cdr *newcdr)
{
   struct ast_cdr *ret;

   if (cdr) {
      ret = cdr;

      while (cdr->next)
         cdr = cdr->next;
      cdr->next = newcdr;
   } else {
      ret = newcdr;
   }

   return ret;
}

/*! \note Don't call without cdr_batch_lock */
static void reset_batch(void)
{
   batch->size = 0;
   batch->head = NULL;
   batch->tail = NULL;
}

/*! \note Don't call without cdr_batch_lock */
static int init_batch(void)
{
   /* This is the single meta-batch used to keep track of all CDRs during the entire life of the program */
   if (!(batch = ast_malloc(sizeof(*batch))))
      return -1;

   reset_batch();

   return 0;
}

static void *do_batch_backend_process(void *data)
{
   struct ast_cdr_batch_item *processeditem;
   struct ast_cdr_batch_item *batchitem = data;

   /* Push each CDR into storage mechanism(s) and free all the memory */
   while (batchitem) {
      post_cdr(batchitem->cdr);
      ast_cdr_free(batchitem->cdr);
      processeditem = batchitem;
      batchitem = batchitem->next;
      ast_free(processeditem);
   }

   return NULL;
}

void ast_cdr_submit_batch(int do_shutdown)
{
   struct ast_cdr_batch_item *oldbatchitems = NULL;
   pthread_t batch_post_thread = AST_PTHREADT_NULL;

   /* if there's no batch, or no CDRs in the batch, then there's nothing to do */
   if (!batch || !batch->head)
      return;

   /* move the old CDRs aside, and prepare a new CDR batch */
   ast_mutex_lock(&cdr_batch_lock);
   oldbatchitems = batch->head;
   reset_batch();
   ast_mutex_unlock(&cdr_batch_lock);

   /* if configured, spawn a new thread to post these CDRs,
      also try to save as much as possible if we are shutting down safely */
   if (batchscheduleronly || do_shutdown) {
      ast_debug(1, "CDR single-threaded batch processing begins now\n");
      do_batch_backend_process(oldbatchitems);
   } else {
      if (ast_pthread_create_detached_background(&batch_post_thread, NULL, do_batch_backend_process, oldbatchitems)) {
         ast_log(LOG_WARNING, "CDR processing thread could not detach, now trying in this thread\n");
         do_batch_backend_process(oldbatchitems);
      } else {
         ast_debug(1, "CDR multi-threaded batch processing begins now\n");
      }
   }
}

static int submit_scheduled_batch(const void *data)
{
   ast_cdr_submit_batch(0);
   /* manually reschedule from this point in time */
   cdr_sched = ast_sched_add(sched, batchtime * 1000, submit_scheduled_batch, NULL);
   /* returning zero so the scheduler does not automatically reschedule */
   return 0;
}

static void submit_unscheduled_batch(void)
{
   /* this is okay since we are not being called from within the scheduler */
   AST_SCHED_DEL(sched, cdr_sched);
   /* schedule the submission to occur ASAP (1 ms) */
   cdr_sched = ast_sched_add(sched, 1, submit_scheduled_batch, NULL);
   /* signal the do_cdr thread to wakeup early and do some work (that lazy thread ;) */
   ast_mutex_lock(&cdr_pending_lock);
   ast_cond_signal(&cdr_pending_cond);
   ast_mutex_unlock(&cdr_pending_lock);
}

void ast_cdr_detach(struct ast_cdr *cdr)
{
   struct ast_cdr_batch_item *newtail;
   int curr;

   if (!cdr)
      return;

   /* maybe they disabled CDR stuff completely, so just drop it */
   if (!enabled) {
      ast_debug(1, "Dropping CDR !\n");
      ast_set_flag(cdr, AST_CDR_FLAG_POST_DISABLED);
      ast_cdr_free(cdr);
      return;
   }

   /* post stuff immediately if we are not in batch mode, this is legacy behaviour */
   if (!batchmode) {
      post_cdr(cdr);
      ast_cdr_free(cdr);
      return;
   }

   /* otherwise, each CDR gets put into a batch list (at the end) */
   ast_debug(1, "CDR detaching from this thread\n");

   /* we'll need a new tail for every CDR */
   if (!(newtail = ast_calloc(1, sizeof(*newtail)))) {
      post_cdr(cdr);
      ast_cdr_free(cdr);
      return;
   }

   /* don't traverse a whole list (just keep track of the tail) */
   ast_mutex_lock(&cdr_batch_lock);
   if (!batch)
      init_batch();
   if (!batch->head) {
      /* new batch is empty, so point the head at the new tail */
      batch->head = newtail;
   } else {
      /* already got a batch with something in it, so just append a new tail */
      batch->tail->next = newtail;
   }
   newtail->cdr = cdr;
   batch->tail = newtail;
   curr = batch->size++;
   ast_mutex_unlock(&cdr_batch_lock);

   /* if we have enough stuff to post, then do it */
   if (curr >= (batchsize - 1))
      submit_unscheduled_batch();
}

static void *do_cdr(void *data)
{
   struct timespec timeout;
   int schedms;
   int numevents = 0;

   for (;;) {
      struct timeval now;
      schedms = ast_sched_wait(sched);
      /* this shouldn't happen, but provide a 1 second default just in case */
      if (schedms <= 0)
         schedms = 1000;
      now = ast_tvadd(ast_tvnow(), ast_samp2tv(schedms, 1000));
      timeout.tv_sec = now.tv_sec;
      timeout.tv_nsec = now.tv_usec * 1000;
      /* prevent stuff from clobbering cdr_pending_cond, then wait on signals sent to it until the timeout expires */
      ast_mutex_lock(&cdr_pending_lock);
      ast_cond_timedwait(&cdr_pending_cond, &cdr_pending_lock, &timeout);
      numevents = ast_sched_runq(sched);
      ast_mutex_unlock(&cdr_pending_lock);
      ast_debug(2, "Processed %d scheduled CDR batches from the run queue\n", numevents);
   }

   return NULL;
}

static char *handle_cli_status(struct ast_cli_entry *e, int cmd, struct ast_cli_args *a)
{
   struct ast_cdr_beitem *beitem=NULL;
   int cnt=0;
   long nextbatchtime=0;

   switch (cmd) {
   case CLI_INIT:
      e->command = "cdr show status";
      e->usage =
         "Usage: cdr show status\n"
         "  Displays the Call Detail Record engine system status.\n";
      return NULL;
   case CLI_GENERATE:
      return NULL;
   }

   if (a->argc > 3)
      return CLI_SHOWUSAGE;

   ast_cli(a->fd, "\n");
   ast_cli(a->fd, "Call Detail Record (CDR) settings\n");
   ast_cli(a->fd, "----------------------------------\n");
   ast_cli(a->fd, "  Logging:                    %s\n", enabled ? "Enabled" : "Disabled");
   ast_cli(a->fd, "  Mode:                       %s\n", batchmode ? "Batch" : "Simple");
   if (enabled) {
      ast_cli(a->fd, "  Log unanswered calls:       %s\n", unanswered ? "Yes" : "No");
      ast_cli(a->fd, "  Log congestion:             %s\n\n", congestion ? "Yes" : "No");
      if (batchmode) {
         ast_cli(a->fd, "* Batch Mode Settings\n");
         ast_cli(a->fd, "  -------------------\n");
         if (batch)
            cnt = batch->size;
         if (cdr_sched > -1)
            nextbatchtime = ast_sched_when(sched, cdr_sched);
         ast_cli(a->fd, "  Safe shutdown:              %s\n", batchsafeshutdown ? "Enabled" : "Disabled");
         ast_cli(a->fd, "  Threading model:            %s\n", batchscheduleronly ? "Scheduler only" : "Scheduler plus separate threads");
         ast_cli(a->fd, "  Current batch size:         %d record%s\n", cnt, ESS(cnt));
         ast_cli(a->fd, "  Maximum batch size:         %d record%s\n", batchsize, ESS(batchsize));
         ast_cli(a->fd, "  Maximum batch time:         %d second%s\n", batchtime, ESS(batchtime));
         ast_cli(a->fd, "  Next batch processing time: %ld second%s\n\n", nextbatchtime, ESS(nextbatchtime));
      }
      ast_cli(a->fd, "* Registered Backends\n");
      ast_cli(a->fd, "  -------------------\n");
      AST_RWLIST_RDLOCK(&be_list);
      if (AST_RWLIST_EMPTY(&be_list)) {
         ast_cli(a->fd, "    (none)\n");
      } else {
         AST_RWLIST_TRAVERSE(&be_list, beitem, list) {
            ast_cli(a->fd, "    %s\n", beitem->name);
         }
      }
      AST_RWLIST_UNLOCK(&be_list);
      ast_cli(a->fd, "\n");
   }

   return CLI_SUCCESS;
}

static char *handle_cli_submit(struct ast_cli_entry *e, int cmd, struct ast_cli_args *a)
{
   switch (cmd) {
   case CLI_INIT:
      e->command = "cdr submit";
      e->usage =
         "Usage: cdr submit\n"
         "       Posts all pending batched CDR data to the configured CDR backend engine modules.\n";
      return NULL;
   case CLI_GENERATE:
      return NULL;
   }
   if (a->argc > 2)
      return CLI_SHOWUSAGE;

   submit_unscheduled_batch();
   ast_cli(a->fd, "Submitted CDRs to backend engines for processing.  This may take a while.\n");

   return CLI_SUCCESS;
}

static struct ast_cli_entry cli_submit = AST_CLI_DEFINE(handle_cli_submit, "Posts all pending batched CDR data");
static struct ast_cli_entry cli_status = AST_CLI_DEFINE(handle_cli_status, "Display the CDR status");

static int do_reload(int reload)
{
   struct ast_config *config;
   struct ast_variable *v;
   int cfg_size;
   int cfg_time;
   int was_enabled;
   int was_batchmode;
   int res = 0;
   struct ast_flags config_flags = { reload ? CONFIG_FLAG_FILEUNCHANGED : 0 };

   if ((config = ast_config_load2("cdr.conf", "cdr", config_flags)) == CONFIG_STATUS_FILEUNCHANGED) {
      return 0;
   }

   ast_mutex_lock(&cdr_batch_lock);

   was_enabled = enabled;
   was_batchmode = batchmode;

   batchsize = BATCH_SIZE_DEFAULT;
   batchtime = BATCH_TIME_DEFAULT;
   batchscheduleronly = BATCH_SCHEDULER_ONLY_DEFAULT;
   batchsafeshutdown = BATCH_SAFE_SHUTDOWN_DEFAULT;
   enabled = ENABLED_DEFAULT;
   batchmode = BATCHMODE_DEFAULT;
   unanswered = UNANSWERED_DEFAULT;
   congestion = CONGESTION_DEFAULT;

   if (config == CONFIG_STATUS_FILEMISSING || config == CONFIG_STATUS_FILEINVALID) {
      ast_mutex_unlock(&cdr_batch_lock);
      return 0;
   }

   /* don't run the next scheduled CDR posting while reloading */
   AST_SCHED_DEL(sched, cdr_sched);

   for (v = ast_variable_browse(config, "general"); v; v = v->next) {
      if (!strcasecmp(v->name, "enable")) {
         enabled = ast_true(v->value);
      } else if (!strcasecmp(v->name, "unanswered")) {
         unanswered = ast_true(v->value);
      } else if (!strcasecmp(v->name, "congestion")) {
         congestion = ast_true(v->value);
      } else if (!strcasecmp(v->name, "batch")) {
         batchmode = ast_true(v->value);
      } else if (!strcasecmp(v->name, "scheduleronly")) {
         batchscheduleronly = ast_true(v->value);
      } else if (!strcasecmp(v->name, "safeshutdown")) {
         batchsafeshutdown = ast_true(v->value);
      } else if (!strcasecmp(v->name, "size")) {
         if (sscanf(v->value, "%30d", &cfg_size) < 1) {
            ast_log(LOG_WARNING, "Unable to convert '%s' to a numeric value.\n", v->value);
         } else if (cfg_size < 0) {
            ast_log(LOG_WARNING, "Invalid maximum batch size '%d' specified, using default\n", cfg_size);
         } else {
            batchsize = cfg_size;
         }
      } else if (!strcasecmp(v->name, "time")) {
         if (sscanf(v->value, "%30d", &cfg_time) < 1) {
            ast_log(LOG_WARNING, "Unable to convert '%s' to a numeric value.\n", v->value);
         } else if (cfg_time < 0) {
            ast_log(LOG_WARNING, "Invalid maximum batch time '%d' specified, using default\n", cfg_time);
         } else {
            batchtime = cfg_time;
         }
      } else if (!strcasecmp(v->name, "endbeforehexten")) {
         ast_set2_flag(&ast_options, ast_true(v->value), AST_OPT_FLAG_END_CDR_BEFORE_H_EXTEN);
      } else if (!strcasecmp(v->name, "initiatedseconds")) {
         ast_set2_flag(&ast_options, ast_true(v->value), AST_OPT_FLAG_INITIATED_SECONDS);
      }
   }

   if (enabled && !batchmode) {
      ast_log(LOG_NOTICE, "CDR simple logging enabled.\n");
   } else if (enabled && batchmode) {
      cdr_sched = ast_sched_add(sched, batchtime * 1000, submit_scheduled_batch, NULL);
      ast_log(LOG_NOTICE, "CDR batch mode logging enabled, first of either size %d or time %d seconds.\n", batchsize, batchtime);
   } else {
      ast_log(LOG_NOTICE, "CDR logging disabled, data will be lost.\n");
   }

   /* if this reload enabled the CDR batch mode, create the background thread
      if it does not exist */
   if (enabled && batchmode && (!was_enabled || !was_batchmode) && (cdr_thread == AST_PTHREADT_NULL)) {
      ast_cond_init(&cdr_pending_cond, NULL);
      if (ast_pthread_create_background(&cdr_thread, NULL, do_cdr, NULL) < 0) {
         ast_log(LOG_ERROR, "Unable to start CDR thread.\n");
         AST_SCHED_DEL(sched, cdr_sched);
      } else {
         ast_cli_register(&cli_submit);
         ast_register_atexit(ast_cdr_engine_term);
         res = 0;
      }
   /* if this reload disabled the CDR and/or batch mode and there is a background thread,
      kill it */
   } else if (((!enabled && was_enabled) || (!batchmode && was_batchmode)) && (cdr_thread != AST_PTHREADT_NULL)) {
      /* wake up the thread so it will exit */
      pthread_cancel(cdr_thread);
      pthread_kill(cdr_thread, SIGURG);
      pthread_join(cdr_thread, NULL);
      cdr_thread = AST_PTHREADT_NULL;
      ast_cond_destroy(&cdr_pending_cond);
      ast_cli_unregister(&cli_submit);
      ast_unregister_atexit(ast_cdr_engine_term);
      res = 0;
      /* if leaving batch mode, then post the CDRs in the batch,
         and don't reschedule, since we are stopping CDR logging */
      if (!batchmode && was_batchmode) {
         ast_cdr_engine_term();
      }
   } else {
      res = 0;
   }

   ast_mutex_unlock(&cdr_batch_lock);
   ast_config_destroy(config);
   manager_event(EVENT_FLAG_SYSTEM, "Reload", "Module: CDR\r\nMessage: CDR subsystem reload requested\r\n");

   return res;
}

int ast_cdr_engine_init(void)
{
   int res;

   sched = ast_sched_context_create();
   if (!sched) {
      ast_log(LOG_ERROR, "Unable to create schedule context.\n");
      return -1;
   }

   ast_cli_register(&cli_status);

   res = do_reload(0);
   if (res) {
      ast_mutex_lock(&cdr_batch_lock);
      res = init_batch();
      ast_mutex_unlock(&cdr_batch_lock);
   }

   return res;
}

/* \note This actually gets called a couple of times at shutdown.  Once, before we start
   hanging up channels, and then again, after the channel hangup timeout expires */
void ast_cdr_engine_term(void)
{
   ast_cdr_submit_batch(batchsafeshutdown);
}

int ast_cdr_engine_reload(void)
{
   return do_reload(1);
}

int ast_cdr_data_add_structure(struct ast_data *tree, struct ast_cdr *cdr, int recur)
{
   struct ast_cdr *tmpcdr;
   struct ast_data *level;
   struct ast_var_t *variables;
   const char *var, *val;
   int x = 1, i;
   char workspace[256];
   char *tmp;

   if (!cdr) {
      return -1;
   }

   for (tmpcdr = cdr; tmpcdr; tmpcdr = (recur ? tmpcdr->next : NULL)) {
      level = ast_data_add_node(tree, "level");
      if (!level) {
         continue;
      }

      ast_data_add_int(level, "level_number", x);

      AST_LIST_TRAVERSE(&tmpcdr->varshead, variables, entries) {
         if (variables && (var = ast_var_name(variables)) &&
               (val = ast_var_value(variables)) && !ast_strlen_zero(var)
               && !ast_strlen_zero(val)) {
            ast_data_add_str(level, var, val);
         } else {
            break;
         }
      }

      for (i = 0; cdr_readonly_vars[i]; i++) {
         workspace[0] = 0; /* null out the workspace, because the cdr_get_tv() won't write anything if time is NULL, so you get old vals */
         ast_cdr_getvar(tmpcdr, cdr_readonly_vars[i], &tmp, workspace, sizeof(workspace), 0, 0);
         if (!tmp) {
            continue;
         }
         ast_data_add_str(level, cdr_readonly_vars[i], tmp);
      }

      x++;
   }

   return 0;
}