cel_pgsql.c

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/*
 * Asterisk -- An open source telephony toolkit.
 *
 * Copyright (C) 2008
 *
 * Steve Murphy - adapted to CEL, from:
 * Matthew D. Hardeman <[email protected]>
 * Adapted from the MySQL CDR logger originally by James Sharp
 *
 * Modified April, 2007; Dec, 2008
 * Steve Murphy <[email protected]>

 * Modified September 2003
 * Matthew D. Hardeman <[email protected]>
 *
 * 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 PostgreSQL CEL logger
 *
 * \author Steve Murphy <[email protected]>
 * PostgreSQL http://www.postgresql.org/
 *
 * See also
 * \arg \ref Config_cel
 * PostgreSQL http://www.postgresql.org/
 * \ingroup cel_drivers
 */

/*** MODULEINFO
   <depend>pgsql</depend>
   <support_level>extended</support_level>
 ***/

#include "asterisk.h"

#include <libpq-fe.h>

#include "asterisk/config.h"
#include "asterisk/options.h"
#include "asterisk/channel.h"
#include "asterisk/cel.h"
#include "asterisk/module.h"
#include "asterisk/logger.h"
#include "asterisk.h"

#define DATE_FORMAT "%Y-%m-%d %T.%6q"

#define PGSQL_BACKEND_NAME "CEL PGSQL backend"

#define PGSQL_MIN_VERSION_SCHEMA 70300

static char *config = "cel_pgsql.conf";

static char *pghostname;
static char *pgdbname;
static char *pgdbuser;
static char *pgpassword;
static char *pgappname;
static char *pgdbport;
static char *table;
static char *schema;

static int connected = 0;
/* Optimization to reduce number of memory allocations */
static int maxsize = 512, maxsize2 = 512;
static int usegmtime = 0;

/*! \brief show_user_def is off by default */
#define CEL_SHOW_USERDEF_DEFAULT 0

/*! TRUE if we should set the eventtype field to USER_DEFINED on user events. */
static unsigned char cel_show_user_def;

AST_MUTEX_DEFINE_STATIC(pgsql_lock);

static PGconn  *conn = NULL;
static PGresult   *result = NULL;

struct columns {
   char *name;
   char *type;
   int len;
   unsigned int notnull:1;
   unsigned int hasdefault:1;
   AST_RWLIST_ENTRY(columns) list;
};

static AST_RWLIST_HEAD_STATIC(psql_columns, columns);

#define LENGTHEN_BUF(size, var_sql) \
   do { \
      /* Lengthen buffer, if necessary */ \
      if (ast_str_strlen(var_sql) + size + 1 > ast_str_size(var_sql)) { \
         if (ast_str_make_space(&var_sql, ((ast_str_size(var_sql) + size + 3) / 512 + 1) * 512) != 0) { \
            ast_log(LOG_ERROR, "Unable to allocate sufficient memory.  Insert CEL '%s:%s' failed.\n", pghostname, table); \
            ast_free(sql); \
            ast_free(sql2); \
            AST_RWLIST_UNLOCK(&psql_columns); \
            return; \
         } \
      } \
   } while (0)

#define LENGTHEN_BUF1(size) \
   LENGTHEN_BUF(size, sql);
#define LENGTHEN_BUF2(size) \
   LENGTHEN_BUF(size, sql2);

static void pgsql_reconnect(void)
{
   struct ast_str *conn_info = ast_str_create(128);
   if (!conn_info) {
      ast_log(LOG_ERROR, "Failed to allocate memory for connection string.\n");
      return;
   }

   if (conn) {
      PQfinish(conn);
      conn = NULL;
   }

   ast_str_set(&conn_info, 0, "host=%s port=%s dbname=%s user=%s",
      pghostname, pgdbport, pgdbname, pgdbuser);

   if (!ast_strlen_zero(pgappname)) {
      ast_str_append(&conn_info, 0, " application_name=%s", pgappname);
   }

   if (!ast_strlen_zero(pgpassword)) {
      ast_str_append(&conn_info, 0, " password=%s", pgpassword);
   }

   conn = PQconnectdb(ast_str_buffer(conn_info));
   ast_free(conn_info);
}


static void pgsql_log(struct ast_event *event)
{
   struct ast_tm tm;
   char timestr[128];
   char *pgerror;
   struct ast_cel_event_record record = {
      .version = AST_CEL_EVENT_RECORD_VERSION,
   };

   if (ast_cel_fill_record(event, &record)) {
      return;
   }

   ast_mutex_lock(&pgsql_lock);

   ast_localtime(&record.event_time, &tm, usegmtime ? "GMT" : NULL);
   ast_strftime(timestr, sizeof(timestr), DATE_FORMAT, &tm);

   if ((!connected) && pghostname && pgdbuser && pgpassword && pgdbname) {
      pgsql_reconnect();
      if (PQstatus(conn) != CONNECTION_BAD) {
         connected = 1;
      } else {
         pgerror = PQerrorMessage(conn);
         ast_log(LOG_ERROR, "cel_pgsql: Unable to connect to database server %s.  Calls will not be logged!\n", pghostname);
         ast_log(LOG_ERROR, "cel_pgsql: Reason: %s\n", pgerror);
         PQfinish(conn);
         conn = NULL;
      }
   }
   if (connected) {
      struct columns *cur;
      struct ast_str *sql = ast_str_create(maxsize), *sql2 = ast_str_create(maxsize2);
      char buf[257];
      char *escapebuf = NULL;
      const char *value;
      int first = 1;
      size_t bufsize = 513;

      escapebuf = ast_malloc(bufsize);
      if (!escapebuf || !sql || !sql2) {
         goto ast_log_cleanup;
      }

      ast_str_set(&sql, 0, "INSERT INTO %s (", table);
      ast_str_set(&sql2, 0, " VALUES (");

#define SEP (first ? "" : ",")

      AST_RWLIST_RDLOCK(&psql_columns);
      AST_RWLIST_TRAVERSE(&psql_columns, cur, list) {
         LENGTHEN_BUF1(strlen(cur->name) + 2);
         ast_str_append(&sql, 0, "%s\"%s\"", SEP, cur->name);

         if (strcmp(cur->name, "eventtime") == 0) {
            if (strncmp(cur->type, "int", 3) == 0) {
               LENGTHEN_BUF2(13);
               ast_str_append(&sql2, 0, "%s%ld", SEP, (long) record.event_time.tv_sec);
            } else if (strncmp(cur->type, "float", 5) == 0) {
               LENGTHEN_BUF2(31);
               ast_str_append(&sql2, 0, "%s%f",
                  SEP,
                  (double) record.event_time.tv_sec +
                  (double) record.event_time.tv_usec / 1000000.0);
            } else {
               /* char, hopefully */
               LENGTHEN_BUF2(31);
               ast_localtime(&record.event_time, &tm, usegmtime ? "GMT" : NULL);
               ast_strftime(buf, sizeof(buf), DATE_FORMAT, &tm);
               ast_str_append(&sql2, 0, "%s'%s'", SEP, buf);
            }
         } else if (strcmp(cur->name, "eventtype") == 0) {
            if (cur->type[0] == 'i') {
               /* Get integer, no need to escape anything */
               LENGTHEN_BUF2(5);
               ast_str_append(&sql2, 0, "%s%d", SEP, (int) record.event_type);
            } else if (strncmp(cur->type, "float", 5) == 0) {
               LENGTHEN_BUF2(31);
               ast_str_append(&sql2, 0, "%s%f", SEP, (double) record.event_type);
            } else {
               /* Char field, probably */
               const char *event_name;

               event_name = (!cel_show_user_def
                  && record.event_type == AST_CEL_USER_DEFINED)
                  ? record.user_defined_name : record.event_name;
               LENGTHEN_BUF2(strlen(event_name) + 1);
               ast_str_append(&sql2, 0, "%s'%s'", SEP, event_name);
            }
         } else if (strcmp(cur->name, "amaflags") == 0) {
            if (strncmp(cur->type, "int", 3) == 0) {
               /* Integer, no need to escape anything */
               LENGTHEN_BUF2(13);
               ast_str_append(&sql2, 0, "%s%u", SEP, record.amaflag);
            } else {
               /* Although this is a char field, there are no special characters in the values for these fields */
               LENGTHEN_BUF2(31);
               ast_str_append(&sql2, 0, "%s'%u'", SEP, record.amaflag);
            }
         } else {
            /* Arbitrary field, could be anything */
            if (strcmp(cur->name, "userdeftype") == 0) {
               value = record.user_defined_name;
            } else if (strcmp(cur->name, "cid_name") == 0) {
               value = record.caller_id_name;
            } else if (strcmp(cur->name, "cid_num") == 0) {
               value = record.caller_id_num;
            } else if (strcmp(cur->name, "cid_ani") == 0) {
               value = record.caller_id_ani;
            } else if (strcmp(cur->name, "cid_rdnis") == 0) {
               value = record.caller_id_rdnis;
            } else if (strcmp(cur->name, "cid_dnid") == 0) {
               value = record.caller_id_dnid;
            } else if (strcmp(cur->name, "exten") == 0) {
               value = record.extension;
            } else if (strcmp(cur->name, "context") == 0) {
               value = record.context;
            } else if (strcmp(cur->name, "channame") == 0) {
               value = record.channel_name;
            } else if (strcmp(cur->name, "appname") == 0) {
               value = record.application_name;
            } else if (strcmp(cur->name, "appdata") == 0) {
               value = record.application_data;
            } else if (strcmp(cur->name, "accountcode") == 0) {
               value = record.account_code;
            } else if (strcmp(cur->name, "peeraccount") == 0) {
               value = record.peer_account;
            } else if (strcmp(cur->name, "uniqueid") == 0) {
               value = record.unique_id;
            } else if (strcmp(cur->name, "linkedid") == 0) {
               value = record.linked_id;
            } else if (strcmp(cur->name, "userfield") == 0) {
               value = record.user_field;
            } else if (strcmp(cur->name, "peer") == 0) {
               value = record.peer;
            } else if (strcmp(cur->name, "extra") == 0) {
               value = record.extra;
            } else {
               value = NULL;
            }

            if (value == NULL) {
               ast_str_append(&sql2, 0, "%sDEFAULT", SEP);
            } else if (strncmp(cur->type, "int", 3) == 0) {
               long long whatever;
               if (value && sscanf(value, "%30lld", &whatever) == 1) {
                  LENGTHEN_BUF2(26);
                  ast_str_append(&sql2, 0, "%s%lld", SEP, whatever);
               } else {
                  LENGTHEN_BUF2(2);
                  ast_str_append(&sql2, 0, "%s0", SEP);
               }
            } else if (strncmp(cur->type, "float", 5) == 0) {
               long double whatever;
               if (value && sscanf(value, "%30Lf", &whatever) == 1) {
                  LENGTHEN_BUF2(51);
                  ast_str_append(&sql2, 0, "%s%30Lf", SEP, whatever);
               } else {
                  LENGTHEN_BUF2(2);
                  ast_str_append(&sql2, 0, "%s0", SEP);
               }
               /* XXX Might want to handle dates, times, and other misc fields here XXX */
            } else {
               if (value) {
                  size_t required_size = strlen(value) * 2 + 1;

                  /* If our argument size exceeds our buffer, grow it,
                   * as PQescapeStringConn() expects the buffer to be
                   * adequitely sized and does *NOT* do size checking.
                   */
                  if (required_size > bufsize) {
                     char *tmpbuf = ast_realloc(escapebuf, required_size);

                     if (!tmpbuf) {
                        AST_RWLIST_UNLOCK(&psql_columns);
                        goto ast_log_cleanup;
                     }

                     escapebuf = tmpbuf;
                     bufsize = required_size;
                  }
                  PQescapeStringConn(conn, escapebuf, value, strlen(value), NULL);
               } else {
                  escapebuf[0] = '\0';
               }
               LENGTHEN_BUF2(strlen(escapebuf) + 3);
               ast_str_append(&sql2, 0, "%s'%s'", SEP, escapebuf);
            }
         }
         first = 0;
      }
      AST_RWLIST_UNLOCK(&psql_columns);
      LENGTHEN_BUF1(ast_str_strlen(sql2) + 2);
      ast_str_append(&sql, 0, ")%s)", ast_str_buffer(sql2));

      ast_debug(3, "Inserting a CEL record: [%s].\n", ast_str_buffer(sql));
      /* Test to be sure we're still connected... */
      /* If we're connected, and connection is working, good. */
      /* Otherwise, attempt reconnect.  If it fails... sorry... */
      if (PQstatus(conn) == CONNECTION_OK) {
         connected = 1;
      } else {
         ast_log(LOG_WARNING, "Connection was lost... attempting to reconnect.\n");
         PQreset(conn);
         if (PQstatus(conn) == CONNECTION_OK) {
            ast_log(LOG_NOTICE, "Connection reestablished.\n");
            connected = 1;
         } else {
            pgerror = PQerrorMessage(conn);
            ast_log(LOG_ERROR, "Unable to reconnect to database server %s. Calls will not be logged!\n", pghostname);
            ast_log(LOG_ERROR, "Reason: %s\n", pgerror);
            PQfinish(conn);
            conn = NULL;
            connected = 0;
            goto ast_log_cleanup;
         }
      }
      result = PQexec(conn, ast_str_buffer(sql));
      if (PQresultStatus(result) != PGRES_COMMAND_OK) {
         pgerror = PQresultErrorMessage(result);
         ast_log(LOG_WARNING, "Failed to insert call detail record into database!\n");
         ast_log(LOG_WARNING, "Reason: %s\n", pgerror);
         ast_log(LOG_WARNING, "Connection may have been lost... attempting to reconnect.\n");
         PQreset(conn);
         if (PQstatus(conn) == CONNECTION_OK) {
            ast_log(LOG_NOTICE, "Connection reestablished.\n");
            connected = 1;
            PQclear(result);
            result = PQexec(conn, ast_str_buffer(sql));
            if (PQresultStatus(result) != PGRES_COMMAND_OK) {
               pgerror = PQresultErrorMessage(result);
               ast_log(LOG_ERROR, "HARD ERROR!  Attempted reconnection failed.  DROPPING CALL RECORD!\n");
               ast_log(LOG_ERROR, "Reason: %s\n", pgerror);
            }
         }
      }
      PQclear(result);

      /* Next time, just allocate buffers that are that big to start with. */
      if (ast_str_strlen(sql) > maxsize) {
         maxsize = ast_str_strlen(sql);
      }
      if (ast_str_strlen(sql2) > maxsize2) {
         maxsize2 = ast_str_strlen(sql2);
      }

ast_log_cleanup:
      ast_free(sql);
      ast_free(sql2);
      ast_free(escapebuf);
   }

   ast_mutex_unlock(&pgsql_lock);
}

static int my_unload_module(void)
{
   struct columns *current;

   ast_cel_backend_unregister(PGSQL_BACKEND_NAME);
   AST_RWLIST_WRLOCK(&psql_columns);
   if (conn) {
      PQfinish(conn);
      conn = NULL;
   }
   if (pghostname) {
      ast_free(pghostname);
      pghostname = NULL;
   }
   if (pgdbname) {
      ast_free(pgdbname);
      pgdbname = NULL;
   }
   if (pgdbuser) {
      ast_free(pgdbuser);
      pgdbuser = NULL;
   }
   if (pgpassword) {
      ast_free(pgpassword);
      pgpassword = NULL;
   }
   if (pgappname) {
      ast_free(pgappname);
      pgappname = NULL;
   }
   if (pgdbport) {
      ast_free(pgdbport);
      pgdbport = NULL;
   }
   if (table) {
      ast_free(table);
      table = NULL;
   }
   if (schema) {
      ast_free(schema);
      schema = NULL;
   }
   while ((current = AST_RWLIST_REMOVE_HEAD(&psql_columns, list))) {
      ast_free(current);
   }
   AST_RWLIST_UNLOCK(&psql_columns);
   return 0;
}

static int unload_module(void)
{
   return my_unload_module();
}

static int process_my_load_module(struct ast_config *cfg)
{
   struct ast_variable *var;
   char *pgerror;
   const char *tmp;
   PGresult *result;
   struct columns *cur;

   if (!(var = ast_variable_browse(cfg, "global"))) {
      ast_log(LOG_WARNING,"CEL pgsql config file missing global section.\n");
      return AST_MODULE_LOAD_DECLINE;
   }
   if (!(tmp = ast_variable_retrieve(cfg,"global","hostname"))) {
      ast_log(LOG_WARNING,"PostgreSQL server hostname not specified.  Assuming unix socket connection\n");
      tmp = "";   /* connect via UNIX-socket by default */
   }
   if (pghostname)
      ast_free(pghostname);
   if (!(pghostname = ast_strdup(tmp))) {
      ast_log(LOG_WARNING,"PostgreSQL Ran out of memory copying host info\n");
      return AST_MODULE_LOAD_DECLINE;
   }
   if (!(tmp = ast_variable_retrieve(cfg, "global", "dbname"))) {
      ast_log(LOG_WARNING,"PostgreSQL database not specified.  Assuming asterisk\n");
      tmp = "asteriskceldb";
   }
   if (pgdbname)
      ast_free(pgdbname);
   if (!(pgdbname = ast_strdup(tmp))) {
      ast_log(LOG_WARNING,"PostgreSQL Ran out of memory copying dbname info\n");
      return AST_MODULE_LOAD_DECLINE;
   }
   if (!(tmp = ast_variable_retrieve(cfg, "global", "user"))) {
      ast_log(LOG_WARNING,"PostgreSQL database user not specified.  Assuming asterisk\n");
      tmp = "asterisk";
   }
   if (pgdbuser)
      ast_free(pgdbuser);
   if (!(pgdbuser = ast_strdup(tmp))) {
      ast_log(LOG_WARNING,"PostgreSQL Ran out of memory copying user info\n");
      return AST_MODULE_LOAD_DECLINE;
   }
   if (!(tmp = ast_variable_retrieve(cfg, "global", "password"))) {
      ast_log(LOG_WARNING, "PostgreSQL database password not specified.  Assuming blank\n");
      tmp = "";
   }
   if (pgpassword)
      ast_free(pgpassword);
   if (!(pgpassword = ast_strdup(tmp))) {
      ast_log(LOG_WARNING,"PostgreSQL Ran out of memory copying password info\n");
      return AST_MODULE_LOAD_DECLINE;
   }
   if (!(tmp = ast_variable_retrieve(cfg, "global", "appname"))) {
      tmp = "";
   }
   if (pgappname) {
      ast_free(pgappname);
   }
   if (!(pgappname = ast_strdup(tmp))) {
      ast_log(LOG_WARNING,"PostgreSQL Ran out of memory copying appname info\n");
      return AST_MODULE_LOAD_DECLINE;
   }

   if (!(tmp = ast_variable_retrieve(cfg,"global","port"))) {
      ast_log(LOG_WARNING,"PostgreSQL database port not specified.  Using default 5432.\n");
      tmp = "5432";
   }
   if (pgdbport)
      ast_free(pgdbport);
   if (!(pgdbport = ast_strdup(tmp))) {
      ast_log(LOG_WARNING,"PostgreSQL Ran out of memory copying port info\n");
      return AST_MODULE_LOAD_DECLINE;
   }
   if (!(tmp = ast_variable_retrieve(cfg, "global", "table"))) {
      ast_log(LOG_WARNING,"CEL table not specified.  Assuming cel\n");
      tmp = "cel";
   }
   if (table)
      ast_free(table);
   if (!(table = ast_strdup(tmp))) {
      return AST_MODULE_LOAD_DECLINE;
   }
   cel_show_user_def = CEL_SHOW_USERDEF_DEFAULT;
   if ((tmp = ast_variable_retrieve(cfg, "global", "show_user_defined"))) {
      cel_show_user_def = ast_true(tmp) ? 1 : 0;
   }
   if ((tmp = ast_variable_retrieve(cfg, "global", "usegmtime"))) {
      usegmtime = ast_true(tmp);
   } else {
      usegmtime = 0;
   }
   if (!(tmp = ast_variable_retrieve(cfg, "global", "schema"))) {
      tmp = "";
   }
   if (schema) {
      ast_free(schema);
   }
   if (!(schema = ast_strdup(tmp))) {
      ast_log(LOG_WARNING,"PostgreSQL Ran out of memory copying schema info\n");
      return AST_MODULE_LOAD_DECLINE;
   }
   if (DEBUG_ATLEAST(3)) {
      if (ast_strlen_zero(pghostname)) {
         ast_log(LOG_DEBUG, "cel_pgsql: using default unix socket\n");
      } else {
         ast_log(LOG_DEBUG, "cel_pgsql: got hostname of %s\n", pghostname);
      }
      ast_log(LOG_DEBUG, "cel_pgsql: got port of %s\n", pgdbport);
      ast_log(LOG_DEBUG, "cel_pgsql: got user of %s\n", pgdbuser);
      ast_log(LOG_DEBUG, "cel_pgsql: got dbname of %s\n", pgdbname);
      ast_log(LOG_DEBUG, "cel_pgsql: got password of %s\n", pgpassword);
      ast_log(LOG_DEBUG, "cel_pgsql: got sql table name of %s\n", table);
      ast_log(LOG_DEBUG, "cel_pgsql: got show_user_defined of %s\n",
         cel_show_user_def ? "Yes" : "No");
   }

   pgsql_reconnect();
   if (PQstatus(conn) != CONNECTION_BAD) {
      char sqlcmd[768];
      char *fname, *ftype, *flen, *fnotnull, *fdef, *tablename, *tmp_tablename;
      int i, rows, version;

      ast_debug(1, "Successfully connected to PostgreSQL database.\n");
      connected = 1;

      version = PQserverVersion(conn);
      /* Remove any schema name from the table */
      if ((tmp_tablename = strrchr(table, '.'))) {
         tmp_tablename++;
      } else {
         tmp_tablename = table;
      }
      tablename = ast_alloca(strlen(tmp_tablename) * 2 + 1);
      PQescapeStringConn(conn, tablename, tmp_tablename, strlen(tmp_tablename), NULL);
      if (version >= PGSQL_MIN_VERSION_SCHEMA) {
         char *schemaname;
         int lenschema;
         lenschema = strlen(schema);
         schemaname = ast_alloca(lenschema * 2 + 1);
         PQescapeStringConn(conn, schemaname, schema, lenschema, NULL);

         snprintf(sqlcmd, sizeof(sqlcmd),
         "SELECT a.attname, t.typname, a.attlen, a.attnotnull, pg_catalog.pg_get_expr(d.adbin, d.adrelid) adsrc, a.atttypmod "
         "FROM (((pg_catalog.pg_class c INNER JOIN pg_catalog.pg_namespace n ON n.oid = c.relnamespace "
                  "AND c.relname = '%s' AND n.nspname = %s%s%s) "
                "INNER JOIN pg_catalog.pg_attribute a ON ("
                    "NOT a.attisdropped) AND a.attnum > 0 AND a.attrelid = c.oid) "
             "INNER JOIN pg_catalog.pg_type t ON t.oid = a.atttypid) "
         "LEFT OUTER JOIN pg_attrdef d ON a.atthasdef AND d.adrelid = a.attrelid "
           "AND d.adnum = a.attnum "
         "ORDER BY n.nspname, c.relname, attnum",
            tablename,
            lenschema == 0 ? "" : "'", lenschema == 0 ? "current_schema()" : schemaname, lenschema == 0 ? "" : "'");
      } else {
         snprintf(sqlcmd, sizeof(sqlcmd),
         "SELECT a.attname, t.typname, a.attlen, a.attnotnull, d.adsrc, a.atttypmod "
         "FROM pg_class c, pg_type t, pg_attribute a "
         "LEFT OUTER JOIN pg_attrdef d ON a.atthasdef AND d.adrelid = a.attrelid "
         "AND d.adnum = a.attnum WHERE c.oid = a.attrelid AND a.atttypid = t.oid "
         "AND (a.attnum > 0) AND c.relname = '%s' ORDER BY c.relname, attnum", tablename);
      }
      /* Query the columns */
      result = PQexec(conn, sqlcmd);
      if (PQresultStatus(result) != PGRES_TUPLES_OK) {
         pgerror = PQresultErrorMessage(result);
         ast_log(LOG_ERROR, "Failed to query database columns: %s\n", pgerror);
         PQclear(result);
         unload_module();
         return AST_MODULE_LOAD_DECLINE;
      }

      rows = PQntuples(result);
      for (i = 0; i < rows; i++) {
         fname = PQgetvalue(result, i, 0);
         ftype = PQgetvalue(result, i, 1);
         flen = PQgetvalue(result, i, 2);
         fnotnull = PQgetvalue(result, i, 3);
         fdef = PQgetvalue(result, i, 4);
         ast_verb(4, "Found column '%s' of type '%s'\n", fname, ftype);
         cur = ast_calloc(1, sizeof(*cur) + strlen(fname) + strlen(ftype) + 2);
         if (cur) {
            sscanf(flen, "%30d", &cur->len);
            cur->name = (char *)cur + sizeof(*cur);
            cur->type = (char *)cur + sizeof(*cur) + strlen(fname) + 1;
            strcpy(cur->name, fname);
            strcpy(cur->type, ftype);
            if (*fnotnull == 't') {
               cur->notnull = 1;
            } else {
               cur->notnull = 0;
            }
            if (!ast_strlen_zero(fdef)) {
               cur->hasdefault = 1;
            } else {
               cur->hasdefault = 0;
            }
            AST_RWLIST_INSERT_TAIL(&psql_columns, cur, list);
         }
      }
      PQclear(result);
   } else {
      pgerror = PQerrorMessage(conn);
      ast_log(LOG_ERROR, "cel_pgsql: Unable to connect to database server %s.  CALLS WILL NOT BE LOGGED!!\n", pghostname);
      ast_log(LOG_ERROR, "cel_pgsql: Reason: %s\n", pgerror);
      connected = 0;
      PQfinish(conn);
      conn = NULL;
   }
   return AST_MODULE_LOAD_SUCCESS;
}

static int my_load_module(int reload)
{
   struct ast_config *cfg;
   struct ast_flags config_flags = { reload ? CONFIG_FLAG_FILEUNCHANGED : 0 };

   if ((cfg = ast_config_load(config, config_flags)) == NULL || cfg == CONFIG_STATUS_FILEINVALID) {
      ast_log(LOG_WARNING, "Unable to load config for PostgreSQL CEL's: %s\n", config);
      return AST_MODULE_LOAD_DECLINE;
   } else if (cfg == CONFIG_STATUS_FILEUNCHANGED) {
      return AST_MODULE_LOAD_SUCCESS;
   }

   if (reload) {
      my_unload_module();
   }

   process_my_load_module(cfg);
   ast_config_destroy(cfg);

   if (ast_cel_backend_register(PGSQL_BACKEND_NAME, pgsql_log)) {
      ast_log(LOG_WARNING, "Unable to subscribe to CEL events for pgsql\n");
      return AST_MODULE_LOAD_DECLINE;
   }

   return AST_MODULE_LOAD_SUCCESS;
}

static int load_module(void)
{
   return my_load_module(0);
}

static int reload(void)
{
   return my_load_module(1);
}

AST_MODULE_INFO(ASTERISK_GPL_KEY, AST_MODFLAG_LOAD_ORDER, "PostgreSQL CEL Backend",
   .support_level = AST_MODULE_SUPPORT_EXTENDED,
   .load = load_module,
   .unload = unload_module,
   .reload = reload,
   .load_pri = AST_MODPRI_CDR_DRIVER,
   .requires = "cel",
);