Sat Nov 1 06:28:23 2008

Asterisk developer's documentation

---

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.
 */


#include "asterisk.h"

ASTERISK_FILE_VERSION(__FILE__, "$Revision: 152811 $")

#include <unistd.h>
#include <stdlib.h>
#include <string.h>
#include <stdio.h>
#include <signal.h>

#include "asterisk/lock.h"
#include "asterisk/channel.h"
#include "asterisk/cdr.h"
#include "asterisk/logger.h"
#include "asterisk/callerid.h"
#include "asterisk/causes.h"
#include "asterisk/options.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"

/*! 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_LIST_ENTRY(ast_cdr_beitem) list;
};

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

#define BATCH_SIZE_DEFAULT 100
#define BATCH_TIME_DEFAULT 300
#define BATCH_SCHEDULER_ONLY_DEFAULT 0
#define BATCH_SAFE_SHUTDOWN_DEFAULT 1

static int enabled;     /*! Is the CDR subsystem enabled ? */
static int unanswered;
static int batchmode;
static int batchsize;
static int batchtime;
static int batchscheduleronly;
static int batchsafeshutdown;

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;


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

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

   AST_LIST_LOCK(&be_list);
   AST_LIST_TRAVERSE(&be_list, i, list) {
      if (!strcasecmp(name, i->name))
         break;
   }
   AST_LIST_UNLOCK(&be_list);

   if (i) {
      ast_log(LOG_WARNING, "Already have a CDR backend called '%s'\n", name);
      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_LIST_LOCK(&be_list);
   AST_LIST_INSERT_HEAD(&be_list, i, list);
   AST_LIST_UNLOCK(&be_list);

   return 0;
}

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

   AST_LIST_LOCK(&be_list);
   AST_LIST_TRAVERSE_SAFE_BEGIN(&be_list, i, list) {
      if (!strcasecmp(name, i->name)) {
         AST_LIST_REMOVE_CURRENT(&be_list, list);
         if (option_verbose > 1)
            ast_verbose(VERBOSE_PREFIX_2 "Unregistered '%s' CDR backend\n", name);
         free(i);
         break;
      }
   }
   AST_LIST_TRAVERSE_SAFE_END;
   AST_LIST_UNLOCK(&be_list);
}

int ast_cdr_isset_unanswered(void)
{
   return unanswered;
}

/*! 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 tv, const char *fmt, char *buf, int bufsize)
{
   if (fmt == NULL) {   /* raw mode */
      snprintf(buf, bufsize, "%ld.%06ld", (long)tv.tv_sec, (long)tv.tv_usec);
   } else {  
      time_t t = tv.tv_sec;
      if (t) {
         struct tm tm;

         ast_localtime(&t, &tm, NULL);
         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->duration);
   else if (!strcasecmp(name, "billsec"))
      snprintf(workspace, workspacelen, "%ld", cdr->billsec);
   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, "uniqueid"))
      ast_copy_string(workspace, cdr->uniqueid, workspacelen);
   else if (!strcasecmp(name, "userfield"))
      ast_copy_string(workspace, cdr->userfield, workspacelen);
   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 *cdr_readonly_vars[] = { "clid", "src", "dst", "dcontext", "channel", "dstchannel",
                "lastapp", "lastdata", "start", "answer", "end", "duration",
                "billsec", "disposition", "amaflags", "accountcode", "uniqueid",
                "userfield", 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;
   
   if (!cdr)  /* don't die if the cdr is null */
      return -1;
   
   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(headp, 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, char *buf, size_t size, char delim, char sep, int recur) 
{
   struct ast_var_t *variables;
   const char *var, *val;
   char *tmp;
   char workspace[256];
   int total = 0, x = 0, i;

   memset(buf, 0, size);

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

      AST_LIST_TRAVERSE(&cdr->varshead, variables, entries) {
         if (variables &&
             (var = ast_var_name(variables)) && (val = ast_var_value(variables)) &&
             !ast_strlen_zero(var) && !ast_strlen_zero(val)) {
            if (ast_build_string(&buf, &size, "level %d: %s%c%s%c", x, var, delim, val, sep)) {
               ast_log(LOG_ERROR, "Data Buffer Size Exceeded!\n");
               break;
            } else
               total++;
         } 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(cdr, cdr_readonly_vars[i], &tmp, workspace, sizeof(workspace), 0, 0);
         if (!tmp)
            continue;
         
         if (ast_build_string(&buf, &size, "level %d: %s%c%s%c", x, cdr_readonly_vars[i], delim, tmp, sep)) {
            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;
      char *chan = S_OR(cdr->channel, "<unknown>");
      if (option_verbose > 1 && !ast_test_flag(cdr, AST_CDR_FLAG_POSTED) && !ast_test_flag(cdr, AST_CDR_FLAG_POST_DISABLED))
         ast_verbose(VERBOSE_PREFIX_2 "CDR on channel '%s' not posted\n", chan);
      if (option_verbose > 1 && ast_tvzero(cdr->end))
         ast_verbose(VERBOSE_PREFIX_2 "CDR on channel '%s' lacks end\n", chan);
      if (option_verbose > 1 && ast_tvzero(cdr->start))
         ast_verbose(VERBOSE_PREFIX_2 "CDR on channel '%s' lacks start\n", chan);

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

struct ast_cdr *ast_cdr_alloc(void)
{
   struct ast_cdr *x = ast_calloc(1, sizeof(struct ast_cdr));
   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 = NULL, *fromvarval = NULL;
      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_REMOVE_CURRENT(headpfrom, entries);
      AST_LIST_INSERT_HEAD(headpto, variablesfrom, 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.");
         to = zcdr; /* safety-- if all there are is locked CDR's, then.... ?? */
         lto = NULL;
      }
   }

   if (ast_test_flag(from, AST_CDR_FLAG_LOCKED)) {
      discard_from = 1;
      if (lto) {
         struct ast_cdr *llfrom = NULL;
         /* 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 */
         llfrom->next = to;
         from = lfrom;
      } else {
         /* save copy of the current *to cdr */
         struct ast_cdr tcdr;
         struct ast_cdr *llfrom = NULL;
         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
            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->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)
{
   char *chan; 

   for (; cdr; cdr = cdr->next) {
      if (!ast_test_flag(cdr, AST_CDR_FLAG_LOCKED)) {
         chan = S_OR(cdr->channel, "<unknown>");
         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);
         if (cdr->disposition < AST_CDR_BUSY)
            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)) {
         if (cdr->disposition < AST_CDR_FAILED)
            cdr->disposition = AST_CDR_FAILED;
      }
   }
}

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

   while (cdr) {
      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 (!ast_test_flag(cdr, AST_CDR_FLAG_LOCKED)) {
         if (cdr->disposition < AST_CDR_NOANSWER)
            cdr->disposition = AST_CDR_NOANSWER;
      }
      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_NORMAL:
         break;
      default:
         res = -1;
      }
   }
   return res;
}

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

void ast_cdr_setapp(struct ast_cdr *cdr, char *app, 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));
      }
   }
}

/* set cid info for one record */
static void set_one_cid(struct ast_cdr *cdr, struct ast_channel *c)
{
   /* Grab source from ANI or normal Caller*ID */
   const char *num = S_OR(c->cid.cid_ani, c->cid.cid_num);
   if (!cdr)
      return;
   if (!ast_strlen_zero(c->cid.cid_name)) {
      if (!ast_strlen_zero(num)) /* both name and number */
         snprintf(cdr->clid, sizeof(cdr->clid), "\"%s\" <%s>", c->cid.cid_name, num);
      else           /* only name */
         ast_copy_string(cdr->clid, c->cid.cid_name, sizeof(cdr->clid));
   } else if (!ast_strlen_zero(num)) { /* only number */
      ast_copy_string(cdr->clid, num, sizeof(cdr->clid));
   } else {          /* nothing known */
      cdr->clid[0] = '\0';
   }
   ast_copy_string(cdr->src, S_OR(num, ""), sizeof(cdr->src));

}
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;
}

int ast_cdr_init(struct ast_cdr *cdr, struct ast_channel *c)
{
   char *chan;

   for ( ; cdr ; cdr = cdr->next) {
      if (!ast_test_flag(cdr, AST_CDR_FLAG_LOCKED)) {
         chan = S_OR(cdr->channel, "<unknown>");
         ast_copy_string(cdr->channel, c->name, sizeof(cdr->channel));
         set_one_cid(cdr, c);

         cdr->disposition = (c->_state == AST_STATE_UP) ?  AST_CDR_ANSWERED : AST_CDR_NULL;
         cdr->amaflags = c->amaflags ? c->amaflags :  ast_default_amaflags;
         ast_copy_string(cdr->accountcode, c->accountcode, sizeof(cdr->accountcode));
         /* Destination information */
         ast_copy_string(cdr->dst, S_OR(c->macroexten,c->exten), sizeof(cdr->dst));
         ast_copy_string(cdr->dcontext, S_OR(c->macrocontext,c->context), sizeof(cdr->dcontext));
         /* Unique call identifier */
         ast_copy_string(cdr->uniqueid, c->uniqueid, sizeof(cdr->uniqueid));
      }
   }
   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;
   }
}

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";
   }
   return "UNKNOWN";
}

/*! Converts AMA flag to printable string */
char *ast_cdr_flags2str(int flag)
{
   switch(flag) {