Fix stuck channel in ARI through the introduction of synchronous bridge actions.
[asterisk/asterisk.git] / res / res_odbc.c
index e7b50d6..bdbe8f2 100644 (file)
@@ -1,7 +1,7 @@
 /*
  * Asterisk -- An open source telephony toolkit.
  *
- * Copyright (C) 1999 - 2005, Digium, Inc.
+ * Copyright (C) 1999 - 2012, Digium, Inc.
  *
  * Mark Spencer <markster@digium.com>
  *
  * 
  * \author Mark Spencer <markster@digium.com>
  * \author Anthony Minessale II <anthmct@yahoo.com>
+ * \author Tilghman Lesher <tilghman@digium.com>
  *
  * \arg See also: \ref cdr_odbc
  */
 
+/*! \li \ref res_odbc.c uses the configuration file \ref res_odbc.conf
+ * \addtogroup configuration_file Configuration Files
+ */
+
+/*! 
+ * \page res_odbc.conf res_odbc.conf
+ * \verbinclude res_odbc.conf.sample
+ */
+
 /*** MODULEINFO
-       <depend>unixodbc</depend>
+       <depend>generic_odbc</depend>
        <depend>ltdl</depend>
+       <support_level>core</support_level>
  ***/
 
 #include "asterisk.h"
@@ -48,6 +59,70 @@ ASTERISK_FILE_VERSION(__FILE__, "$Revision$")
 #include "asterisk/res_odbc.h"
 #include "asterisk/time.h"
 #include "asterisk/astobj2.h"
+#include "asterisk/app.h"
+#include "asterisk/strings.h"
+#include "asterisk/threadstorage.h"
+#include "asterisk/data.h"
+
+/*** DOCUMENTATION
+       <function name="ODBC" language="en_US">
+               <synopsis>
+                       Controls ODBC transaction properties.
+               </synopsis>
+               <syntax>
+                       <parameter name="property" required="true">
+                               <enumlist>
+                                       <enum name="transaction">
+                                               <para>Gets or sets the active transaction ID.  If set, and the transaction ID does not
+                                               exist and a <replaceable>database name</replaceable> is specified as an argument, it will be created.</para>
+                                       </enum>
+                                       <enum name="forcecommit">
+                                               <para>Controls whether a transaction will be automatically committed when the channel
+                                               hangs up.  Defaults to false.  If a <replaceable>transaction ID</replaceable> is specified in the optional argument,
+                                               the property will be applied to that ID, otherwise to the current active ID.</para>
+                                       </enum>
+                                       <enum name="isolation">
+                                               <para>Controls the data isolation on uncommitted transactions.  May be one of the
+                                               following: <literal>read_committed</literal>, <literal>read_uncommitted</literal>,
+                                               <literal>repeatable_read</literal>, or <literal>serializable</literal>.  Defaults to the
+                                               database setting in <filename>res_odbc.conf</filename> or <literal>read_committed</literal>
+                                               if not specified.  If a <replaceable>transaction ID</replaceable> is specified as an optional argument, it will be
+                                               applied to that ID, otherwise the current active ID.</para>
+                                       </enum>
+                               </enumlist>
+                       </parameter>
+                       <parameter name="argument" required="false" />
+               </syntax>
+               <description>
+                       <para>The ODBC() function allows setting several properties to influence how a connected
+                       database processes transactions.</para>
+               </description>
+       </function>
+       <application name="ODBC_Commit" language="en_US">
+               <synopsis>
+                       Commits a currently open database transaction.
+               </synopsis>
+               <syntax>
+                       <parameter name="transaction ID" required="no" />
+               </syntax>
+               <description>
+                       <para>Commits the database transaction specified by <replaceable>transaction ID</replaceable>
+                       or the current active transaction, if not specified.</para>
+               </description>
+       </application>
+       <application name="ODBC_Rollback" language="en_US">
+               <synopsis>
+                       Rollback a currently open database transaction.
+               </synopsis>
+               <syntax>
+                       <parameter name="transaction ID" required="no" />
+               </syntax>
+               <description>
+                       <para>Rolls back the database transaction specified by <replaceable>transaction ID</replaceable>
+                       or the current active transaction, if not specified.</para>
+               </description>
+       </application>
+ ***/
 
 struct odbc_class
 {
@@ -58,22 +133,271 @@ struct odbc_class
        char *password;
        char *sanitysql;
        SQLHENV env;
-       unsigned int haspool:1;              /* Boolean - TDS databases need this */
-       unsigned int delme:1;                /* Purge the class */
-       unsigned int backslash_is_escape:1;  /* On this database, the backslash is a native escape sequence */
-       unsigned int limit;                  /* 1023 wasn't enough for some people */
-       unsigned int count;                  /* Running count of pooled connections */
-       unsigned int idlecheck;              /* Recheck the connection if it is idle for this long */
+       unsigned int haspool:1;              /*!< Boolean - TDS databases need this */
+       unsigned int delme:1;                /*!< Purge the class */
+       unsigned int backslash_is_escape:1;  /*!< On this database, the backslash is a native escape sequence */
+       unsigned int forcecommit:1;          /*!< Should uncommitted transactions be auto-committed on handle release? */
+       unsigned int isolation;              /*!< Flags for how the DB should deal with data in other, uncommitted transactions */
+       unsigned int limit;                  /*!< Maximum number of database handles we will allow */
+       int count;                           /*!< Running count of pooled connections */
+       unsigned int idlecheck;              /*!< Recheck the connection if it is idle for this long (in seconds) */
+       unsigned int conntimeout;            /*!< Maximum time the connection process should take */
+       /*! When a connection fails, cache that failure for how long? */
+       struct timeval negative_connection_cache;
+       /*! When a connection fails, when did that last occur? */
+       struct timeval last_negative_connect;
+       /*! List of handles associated with this class */
        struct ao2_container *obj_container;
 };
 
-struct ao2_container *class_container;
+static struct ao2_container *class_container;
 
 static AST_RWLIST_HEAD_STATIC(odbc_tables, odbc_cache_tables);
 
 static odbc_status odbc_obj_connect(struct odbc_obj *obj);
 static odbc_status odbc_obj_disconnect(struct odbc_obj *obj);
 static int odbc_register_class(struct odbc_class *class, int connect);
+static void odbc_txn_free(void *data);
+static void odbc_release_obj2(struct odbc_obj *obj, struct odbc_txn_frame *tx);
+
+AST_THREADSTORAGE(errors_buf);
+
+static const struct ast_datastore_info txn_info = {
+       .type = "ODBC_Transaction",
+       .destroy = odbc_txn_free,
+};
+
+struct odbc_txn_frame {
+       AST_LIST_ENTRY(odbc_txn_frame) list;
+       struct ast_channel *owner;
+       struct odbc_obj *obj;        /*!< Database handle within which transacted statements are run */
+       /*!\brief Is this record the current active transaction within the channel?
+        * Note that the active flag is really only necessary for statements which
+        * are triggered from the dialplan, as there isn't a direct correlation
+        * between multiple statements.  Applications wishing to use transactions
+        * may simply perform each statement on the same odbc_obj, which keeps the
+        * transaction persistent.
+        */
+       unsigned int active:1;
+       unsigned int forcecommit:1;     /*!< Should uncommitted transactions be auto-committed on handle release? */
+       unsigned int isolation;         /*!< Flags for how the DB should deal with data in other, uncommitted transactions */
+       char name[0];                   /*!< Name of this transaction ID */
+};
+
+#define DATA_EXPORT_ODBC_CLASS(MEMBER)                         \
+       MEMBER(odbc_class, name, AST_DATA_STRING)               \
+       MEMBER(odbc_class, dsn, AST_DATA_STRING)                \
+       MEMBER(odbc_class, username, AST_DATA_STRING)           \
+       MEMBER(odbc_class, password, AST_DATA_PASSWORD)         \
+       MEMBER(odbc_class, limit, AST_DATA_INTEGER)             \
+       MEMBER(odbc_class, count, AST_DATA_INTEGER)             \
+       MEMBER(odbc_class, forcecommit, AST_DATA_BOOLEAN)
+
+AST_DATA_STRUCTURE(odbc_class, DATA_EXPORT_ODBC_CLASS);
+
+static const char *isolation2text(int iso)
+{
+       if (iso == SQL_TXN_READ_COMMITTED) {
+               return "read_committed";
+       } else if (iso == SQL_TXN_READ_UNCOMMITTED) {
+               return "read_uncommitted";
+       } else if (iso == SQL_TXN_SERIALIZABLE) {
+               return "serializable";
+       } else if (iso == SQL_TXN_REPEATABLE_READ) {
+               return "repeatable_read";
+       } else {
+               return "unknown";
+       }
+}
+
+static int text2isolation(const char *txt)
+{
+       if (strncasecmp(txt, "read_", 5) == 0) {
+               if (strncasecmp(txt + 5, "c", 1) == 0) {
+                       return SQL_TXN_READ_COMMITTED;
+               } else if (strncasecmp(txt + 5, "u", 1) == 0) {
+                       return SQL_TXN_READ_UNCOMMITTED;
+               } else {
+                       return 0;
+               }
+       } else if (strncasecmp(txt, "ser", 3) == 0) {
+               return SQL_TXN_SERIALIZABLE;
+       } else if (strncasecmp(txt, "rep", 3) == 0) {
+               return SQL_TXN_REPEATABLE_READ;
+       } else {
+               return 0;
+       }
+}
+
+static struct odbc_txn_frame *find_transaction(struct ast_channel *chan, struct odbc_obj *obj, const char *name, int active)
+{
+       struct ast_datastore *txn_store;
+       AST_LIST_HEAD(, odbc_txn_frame) *oldlist;
+       struct odbc_txn_frame *txn = NULL;
+
+       if (!chan && obj && obj->txf && obj->txf->owner) {
+               chan = obj->txf->owner;
+       } else if (!chan) {
+               /* No channel == no transaction */
+               return NULL;
+       }
+
+       ast_channel_lock(chan);
+       if ((txn_store = ast_channel_datastore_find(chan, &txn_info, NULL))) {
+               oldlist = txn_store->data;
+       } else {
+               /* Need to create a new datastore */
+               if (!(txn_store = ast_datastore_alloc(&txn_info, NULL))) {
+                       ast_log(LOG_ERROR, "Unable to allocate a new datastore.  Cannot create a new transaction.\n");
+                       ast_channel_unlock(chan);
+                       return NULL;
+               }
+
+               if (!(oldlist = ast_calloc(1, sizeof(*oldlist)))) {
+                       ast_log(LOG_ERROR, "Unable to allocate datastore list head.  Cannot create a new transaction.\n");
+                       ast_datastore_free(txn_store);
+                       ast_channel_unlock(chan);
+                       return NULL;
+               }
+
+               txn_store->data = oldlist;
+               AST_LIST_HEAD_INIT(oldlist);
+               ast_channel_datastore_add(chan, txn_store);
+       }
+
+       AST_LIST_LOCK(oldlist);
+       ast_channel_unlock(chan);
+
+       /* Scanning for an object is *fast*.  Scanning for a name is much slower. */
+       if (obj != NULL || active == 1) {
+               AST_LIST_TRAVERSE(oldlist, txn, list) {
+                       if (txn->obj == obj || txn->active) {
+                               AST_LIST_UNLOCK(oldlist);
+                               return txn;
+                       }
+               }
+       }
+
+       if (name != NULL) {
+               AST_LIST_TRAVERSE(oldlist, txn, list) {
+                       if (!strcasecmp(txn->name, name)) {
+                               AST_LIST_UNLOCK(oldlist);
+                               return txn;
+                       }
+               }
+       }
+
+       /* Nothing found, create one */
+       if (name && obj && (txn = ast_calloc(1, sizeof(*txn) + strlen(name) + 1))) {
+               struct odbc_txn_frame *otxn;
+
+               strcpy(txn->name, name); /* SAFE */
+               txn->obj = obj;
+               txn->isolation = obj->parent->isolation;
+               txn->forcecommit = obj->parent->forcecommit;
+               txn->owner = chan;
+               txn->active = 1;
+
+               /* On creation, the txn becomes active, and all others inactive */
+               AST_LIST_TRAVERSE(oldlist, otxn, list) {
+                       otxn->active = 0;
+               }
+               AST_LIST_INSERT_TAIL(oldlist, txn, list);
+
+               obj->txf = txn;
+               obj->tx = 1;
+       }
+       AST_LIST_UNLOCK(oldlist);
+
+       return txn;
+}
+
+static struct odbc_txn_frame *release_transaction(struct odbc_txn_frame *tx)
+{
+       if (!tx) {
+               return NULL;
+       }
+
+       ast_debug(2, "release_transaction(%p) called (tx->obj = %p, tx->obj->txf = %p)\n", tx, tx->obj, tx->obj ? tx->obj->txf : NULL);
+
+       /* If we have an owner, disassociate */
+       if (tx->owner) {
+               struct ast_datastore *txn_store;
+               AST_LIST_HEAD(, odbc_txn_frame) *oldlist;
+
+               ast_channel_lock(tx->owner);
+               if ((txn_store = ast_channel_datastore_find(tx->owner, &txn_info, NULL))) {
+                       oldlist = txn_store->data;
+                       AST_LIST_LOCK(oldlist);
+                       AST_LIST_REMOVE(oldlist, tx, list);
+                       AST_LIST_UNLOCK(oldlist);
+               }
+               ast_channel_unlock(tx->owner);
+               tx->owner = NULL;
+       }
+
+       if (tx->obj) {
+               /* If we have any uncommitted transactions, they are handled when we release the object */
+               struct odbc_obj *obj = tx->obj;
+               /* Prevent recursion during destruction */
+               tx->obj->txf = NULL;
+               tx->obj = NULL;
+               odbc_release_obj2(obj, tx);
+       }
+       ast_free(tx);
+       return NULL;
+}
+
+static void odbc_txn_free(void *vdata)
+{
+       struct odbc_txn_frame *tx;
+       AST_LIST_HEAD(, odbc_txn_frame) *oldlist = vdata;
+
+       ast_debug(2, "odbc_txn_free(%p) called\n", vdata);
+
+       AST_LIST_LOCK(oldlist);
+       while ((tx = AST_LIST_REMOVE_HEAD(oldlist, list))) {
+               release_transaction(tx);
+       }
+       AST_LIST_UNLOCK(oldlist);
+       AST_LIST_HEAD_DESTROY(oldlist);
+       ast_free(oldlist);
+}
+
+static int mark_transaction_active(struct ast_channel *chan, struct odbc_txn_frame *tx)
+{
+       struct ast_datastore *txn_store;
+       AST_LIST_HEAD(, odbc_txn_frame) *oldlist;
+       struct odbc_txn_frame *active = NULL, *txn;
+
+       if (!chan && tx && tx->owner) {
+               chan = tx->owner;
+       }
+
+       if (!chan) {
+               return -1;
+       }
+
+       ast_channel_lock(chan);
+       if (!(txn_store = ast_channel_datastore_find(chan, &txn_info, NULL))) {
+               ast_channel_unlock(chan);
+               return -1;
+       }
+
+       oldlist = txn_store->data;
+       AST_LIST_LOCK(oldlist);
+       AST_LIST_TRAVERSE(oldlist, txn, list) {
+               if (txn == tx) {
+                       txn->active = 1;
+                       active = txn;
+               } else {
+                       txn->active = 0;
+               }
+       }
+       AST_LIST_UNLOCK(oldlist);
+       ast_channel_unlock(chan);
+       return active ? 0 : -1;
+}
 
 static void odbc_class_destructor(void *data)
 {
@@ -81,12 +405,15 @@ static void odbc_class_destructor(void *data)
        /* Due to refcounts, we can safely assume that any objects with a reference
         * to us will prevent our destruction, so we don't need to worry about them.
         */
-       if (class->username)
+       if (class->username) {
                ast_free(class->username);
-       if (class->password)
+       }
+       if (class->password) {
                ast_free(class->password);
-       if (class->sanitysql)
+       }
+       if (class->sanitysql) {
                ast_free(class->sanitysql);
+       }
        ao2_ref(class->obj_container, -1);
        SQLFreeHandle(SQL_HANDLE_ENV, class->env);
 }
@@ -99,9 +426,10 @@ static int null_hash_fn(const void *obj, const int flags)
 static void odbc_obj_destructor(void *data)
 {
        struct odbc_obj *obj = data;
+       struct odbc_class *class = obj->parent;
+       obj->parent = NULL;
        odbc_obj_disconnect(obj);
-       ast_mutex_destroy(&obj->lock);
-       ao2_ref(obj->parent, -1);
+       ao2_ref(class, -1);
 }
 
 static void destroy_table_cache(struct odbc_cache_tables *table) {
@@ -118,11 +446,12 @@ static void destroy_table_cache(struct odbc_cache_tables *table) {
 
 /*!
  * \brief Find or create an entry describing the table specified.
- * \param obj An active ODBC handle on which to query the table
- * \param table Tablename to describe
+ * \param database Name of an ODBC class on which to query the table
+ * \param tablename Tablename to describe
  * \retval A structure describing the table layout, or NULL, if the table is not found or another error occurs.
  * When a structure is returned, the contained columns list will be
  * rdlock'ed, to ensure that it will be retained in memory.
+ * \since 1.6.1
  */
 struct odbc_cache_tables *ast_odbc_find_table(const char *database, const char *tablename)
 {
@@ -151,18 +480,19 @@ struct odbc_cache_tables *ast_odbc_find_table(const char *database, const char *
 
        if (!obj) {
                ast_log(LOG_WARNING, "Unable to retrieve database handle for table description '%s@%s'\n", tablename, database);
+               AST_RWLIST_UNLOCK(&odbc_tables);
                return NULL;
        }
 
        /* Table structure not already cached; build it now. */
+       ao2_lock(obj);
        do {
-retry:
                res = SQLAllocHandle(SQL_HANDLE_STMT, obj->con, &stmt);
                if ((res != SQL_SUCCESS) && (res != SQL_SUCCESS_WITH_INFO)) {
                        if (try == 0) {
                                try = 1;
                                ast_odbc_sanity_check(obj);
-                               goto retry;
+                               continue;
                        }
                        ast_log(LOG_WARNING, "SQL Alloc Handle failed on connection '%s'!\n", database);
                        break;
@@ -174,7 +504,7 @@ retry:
                                try = 1;
                                SQLFreeHandle(SQL_HANDLE_STMT, stmt);
                                ast_odbc_sanity_check(obj);
-                               goto retry;
+                               continue;
                        }
                        ast_log(LOG_ERROR, "Unable to query database columns on connection '%s'.\n", database);
                        break;
@@ -224,7 +554,9 @@ retry:
 
                AST_RWLIST_INSERT_TAIL(&odbc_tables, tableptr, list);
                AST_RWLIST_RDLOCK(&(tableptr->columns));
-       } while (0);
+               break;
+       } while (1);
+       ao2_unlock(obj);
 
        AST_RWLIST_UNLOCK(&odbc_tables);
 
@@ -271,20 +603,26 @@ SQLHSTMT ast_odbc_direct_execute(struct odbc_obj *obj, SQLHSTMT (*exec_cb)(struc
        int attempt;
        SQLHSTMT stmt;
 
+       ao2_lock(obj);
+
        for (attempt = 0; attempt < 2; attempt++) {
                stmt = exec_cb(obj, data);
 
                if (stmt) {
                        break;
-               } else {
-                       obj->up = 0;
-                       ast_log(LOG_WARNING, "SQL Exec Direct failed.  Attempting a reconnect...\n");
-
-                       odbc_obj_disconnect(obj);
-                       odbc_obj_connect(obj);
+               } else if (obj->tx) {
+                       ast_log(LOG_WARNING, "Failed to execute, but unable to reconnect, as we're transactional.\n");
+                       break;
+               } else if (attempt == 0) {
+                       ast_log(LOG_WARNING, "SQL Execute error! Verifying connection to %s [%s]...\n", obj->parent->name, obj->parent->dsn);
+               }
+               if (!ast_odbc_sanity_check(obj)) {
+                       break;
                }
        }
 
+       ao2_unlock(obj);
+
        return stmt;
 }
 
@@ -296,6 +634,8 @@ SQLHSTMT ast_odbc_prepare_and_execute(struct odbc_obj *obj, SQLHSTMT (*prepare_c
        unsigned char state[10], diagnostic[256];
        SQLHSTMT stmt;
 
+       ao2_lock(obj);
+
        for (attempt = 0; attempt < 2; attempt++) {
                /* This prepare callback may do more than just prepare -- it may also
                 * bind parameters, bind results, etc.  The real key, here, is that
@@ -319,34 +659,47 @@ SQLHSTMT ast_odbc_prepare_and_execute(struct odbc_obj *obj, SQLHSTMT (*prepare_c
                                        }
                                }
 
-                               ast_log(LOG_WARNING, "SQL Execute error %d! Attempting a reconnect...\n", res);
-                               SQLFreeHandle(SQL_HANDLE_STMT, stmt);
-                               stmt = NULL;
+                               if (obj->tx) {
+                                       ast_log(LOG_WARNING, "SQL Execute error, but unable to reconnect, as we're transactional.\n");
+                                       break;
+                               } else {
+                                       ast_log(LOG_WARNING, "SQL Execute error %d! Verifying connection to %s [%s]...\n", res, obj->parent->name, obj->parent->dsn);
+                                       SQLFreeHandle(SQL_HANDLE_STMT, stmt);
+                                       stmt = NULL;
 
-                               obj->up = 0;
-                               /*
-                                * While this isn't the best way to try to correct an error, this won't automatically
-                                * fail when the statement handle invalidates.
-                                */
-                               ast_odbc_sanity_check(obj);
-                               continue;
-                       } else
+                                       obj->up = 0;
+                                       /*
+                                        * While this isn't the best way to try to correct an error, this won't automatically
+                                        * fail when the statement handle invalidates.
+                                        */
+                                       if (!ast_odbc_sanity_check(obj)) {
+                                               break;
+                                       }
+                                       continue;
+                               }
+                       } else {
                                obj->last_used = ast_tvnow();
+                       }
                        break;
-               } else if (attempt == 0)
+               } else if (attempt == 0) {
                        ast_odbc_sanity_check(obj);
+               }
        }
 
+       ao2_unlock(obj);
+
        return stmt;
 }
 
-int ast_odbc_smart_execute(struct odbc_obj *obj, SQLHSTMT stmt) 
+int ast_odbc_smart_execute(struct odbc_obj *obj, SQLHSTMT stmt)
 {
        int res = 0, i;
        SQLINTEGER nativeerror=0, numfields=0;
        SQLSMALLINT diagbytes=0;
        unsigned char state[10], diagnostic[256];
 
+       ao2_lock(obj);
+
        res = SQLExecute(stmt);
        if ((res != SQL_SUCCESS) && (res != SQL_SUCCESS_WITH_INFO) && (res != SQL_NO_DATA)) {
                if (res == SQL_ERROR) {
@@ -360,12 +713,31 @@ int ast_odbc_smart_execute(struct odbc_obj *obj, SQLHSTMT stmt)
                                }
                        }
                }
-       } else
+       } else {
                obj->last_used = ast_tvnow();
-       
+       }
+
+       ao2_unlock(obj);
+
        return res;
 }
 
+SQLRETURN ast_odbc_ast_str_SQLGetData(struct ast_str **buf, int pmaxlen, SQLHSTMT StatementHandle, SQLUSMALLINT ColumnNumber, SQLSMALLINT TargetType, SQLLEN *StrLen_or_Ind)
+{
+       SQLRETURN res;
+
+       if (pmaxlen == 0) {
+               if (SQLGetData(StatementHandle, ColumnNumber, TargetType, ast_str_buffer(*buf), 0, StrLen_or_Ind) == SQL_SUCCESS_WITH_INFO) {
+                       ast_str_make_space(buf, *StrLen_or_Ind + 1);
+               }
+       } else if (pmaxlen > 0) {
+               ast_str_make_space(buf, pmaxlen);
+       }
+       res = SQLGetData(StatementHandle, ColumnNumber, TargetType, ast_str_buffer(*buf), ast_str_size(*buf), StrLen_or_Ind);
+       ast_str_update(*buf);
+
+       return res;
+}
 
 int ast_odbc_sanity_check(struct odbc_obj *obj) 
 {
@@ -394,7 +766,7 @@ int ast_odbc_sanity_check(struct odbc_obj *obj)
                SQLFreeHandle (SQL_HANDLE_STMT, stmt);
        }
 
-       if (!obj->up) { /* Try to reconnect! */
+       if (!obj->up && !obj->tx) { /* Try to reconnect! */
                ast_log(LOG_WARNING, "Connection is down attempting to reconnect...\n");
                odbc_obj_disconnect(obj);
                odbc_obj_connect(obj);
@@ -409,7 +781,8 @@ static int load_odbc_config(void)
        struct ast_variable *v;
        char *cat;
        const char *dsn, *username, *password, *sanitysql;
-       int enabled, pooling, limit, bse;
+       int enabled, pooling, limit, bse, conntimeout, forcecommit, isolation;
+       struct timeval ncache = { 0, 0 };
        unsigned int idlecheck;
        int preconnect = 0, res = 0;
        struct ast_flags config_flags = { 0 };
@@ -435,6 +808,9 @@ static int load_odbc_config(void)
                        pooling = 0;
                        limit = 0;
                        bse = 1;
+                       conntimeout = 10;
+                       forcecommit = 0;
+                       isolation = SQL_TXN_READ_COMMITTED;
                        for (v = ast_variable_browse(config, cat); v; v = v->next) {
                                if (!strcasecmp(v->name, "pooling")) {
                                        if (ast_true(v->value))
@@ -444,7 +820,7 @@ static int load_odbc_config(void)
                                        if (ast_false(v->value))
                                                pooling = 1;
                                } else if (!strcasecmp(v->name, "limit")) {
-                                       sscanf(v->value, "%d", &limit);
+                                       sscanf(v->value, "%30d", &limit);
                                        if (ast_true(v->value) && !limit) {
                                                ast_log(LOG_WARNING, "Limit should be a number, not a boolean: '%s'.  Setting limit to 1023 for ODBC class '%s'.\n", v->value, cat);
                                                limit = 1023;
@@ -454,7 +830,7 @@ static int load_odbc_config(void)
                                                break;
                                        }
                                } else if (!strcasecmp(v->name, "idlecheck")) {
-                                       sscanf(v->value, "%d", &idlecheck);
+                                       sscanf(v->value, "%30u", &idlecheck);
                                } else if (!strcasecmp(v->name, "enabled")) {
                                        enabled = ast_true(v->value);
                                } else if (!strcasecmp(v->name, "pre-connect")) {
@@ -469,6 +845,29 @@ static int load_odbc_config(void)
                                        sanitysql = v->value;
                                } else if (!strcasecmp(v->name, "backslash_is_escape")) {
                                        bse = ast_true(v->value);
+                               } else if (!strcasecmp(v->name, "connect_timeout")) {
+                                       if (sscanf(v->value, "%d", &conntimeout) != 1 || conntimeout < 1) {
+                                               ast_log(LOG_WARNING, "connect_timeout must be a positive integer\n");
+                                               conntimeout = 10;
+                                       }
+                               } else if (!strcasecmp(v->name, "negative_connection_cache")) {
+                                       double dncache;
+                                       if (sscanf(v->value, "%lf", &dncache) != 1 || dncache < 0) {
+                                               ast_log(LOG_WARNING, "negative_connection_cache must be a non-negative integer\n");
+                                               /* 5 minutes sounds like a reasonable default */
+                                               ncache.tv_sec = 300;
+                                               ncache.tv_usec = 0;
+                                       } else {
+                                               ncache.tv_sec = (int)dncache;
+                                               ncache.tv_usec = (dncache - ncache.tv_sec) * 1000000;
+                                       }
+                               } else if (!strcasecmp(v->name, "forcecommit")) {
+                                       forcecommit = ast_true(v->value);
+                               } else if (!strcasecmp(v->name, "isolation")) {
+                                       if ((isolation = text2isolation(v->value)) == 0) {
+                                               ast_log(LOG_ERROR, "Unrecognized value for 'isolation': '%s' in section '%s'\n", v->value, cat);
+                                               isolation = SQL_TXN_READ_COMMITTED;
+                                       }
                                }
                        }
 
@@ -502,7 +901,11 @@ static int load_odbc_config(void)
                                }
 
                                new->backslash_is_escape = bse ? 1 : 0;
+                               new->forcecommit = forcecommit ? 1 : 0;
+                               new->isolation = isolation;
                                new->idlecheck = idlecheck;
+                               new->conntimeout = conntimeout;
+                               new->negative_connection_cache = ncache;
 
                                if (cat)
                                        ast_copy_string(new->name, cat, sizeof(new->name));
@@ -534,7 +937,7 @@ static int load_odbc_config(void)
 
 static char *handle_cli_odbc_show(struct ast_cli_entry *e, int cmd, struct ast_cli_args *a)
 {
-       struct ao2_iterator aoi = ao2_iterator_init(class_container, 0);
+       struct ao2_iterator aoi;
        struct odbc_class *class;
        struct odbc_obj *current;
        int length = 0;
@@ -553,14 +956,17 @@ static char *handle_cli_odbc_show(struct ast_cli_entry *e, int cmd, struct ast_c
                if (a->pos != 2)
                        return NULL;
                length = strlen(a->word);
+               aoi = ao2_iterator_init(class_container, 0);
                while ((class = ao2_iterator_next(&aoi))) {
                        if (!strncasecmp(a->word, class->name, length) && ++which > a->n) {
                                ret = ast_strdup(class->name);
-                               ao2_ref(class, -1);
-                               break;
                        }
                        ao2_ref(class, -1);
+                       if (ret) {
+                               break;
+                       }
                }
+               ao2_iterator_destroy(&aoi);
                if (!ret && !strncasecmp(a->word, "all", length) && ++which > a->n) {
                        ret = ast_strdup("all");
                }
@@ -573,7 +979,13 @@ static char *handle_cli_odbc_show(struct ast_cli_entry *e, int cmd, struct ast_c
        while ((class = ao2_iterator_next(&aoi))) {
                if ((a->argc == 2) || (a->argc == 3 && !strcmp(a->argv[2], "all")) || (!strcmp(a->argv[2], class->name))) {
                        int count = 0;
+                       char timestr[80];
+                       struct ast_tm tm;
+
+                       ast_localtime(&class->last_negative_connect, &tm, NULL);
+                       ast_strftime(timestr, sizeof(timestr), "%Y-%m-%d %T", &tm);
                        ast_cli(a->fd, "  Name:   %s\n  DSN:    %s\n", class->name, class->dsn);
+                       ast_cli(a->fd, "    Last connection attempt: %s\n", timestr);
 
                        if (class->haspool) {
                                struct ao2_iterator aoi2 = ao2_iterator_init(class->obj_container, 0);
@@ -581,7 +993,7 @@ static char *handle_cli_odbc_show(struct ast_cli_entry *e, int cmd, struct ast_c
                                ast_cli(a->fd, "  Pooled: Yes\n  Limit:  %d\n  Connections in use: %d\n", class->limit, class->count);
 
                                while ((current = ao2_iterator_next(&aoi2))) {
-                                       ast_mutex_lock(&current->lock);
+                                       ao2_lock(current);
 #ifdef DEBUG_THREADS
                                        ast_cli(a->fd, "    - Connection %d: %s (%s:%d %s)\n", ++count,
                                                current->used ? "in use" :
@@ -592,21 +1004,25 @@ static char *handle_cli_odbc_show(struct ast_cli_entry *e, int cmd, struct ast_c
                                                current->used ? "in use" :
                                                current->up && ast_odbc_sanity_check(current) ? "connected" : "disconnected");
 #endif
-                                       ast_mutex_unlock(&current->lock);
+                                       ao2_unlock(current);
                                        ao2_ref(current, -1);
                                }
+                               ao2_iterator_destroy(&aoi2);
                        } else {
-                               /* Should only ever be one of these */
+                               /* Should only ever be one of these (unless there are transactions) */
                                struct ao2_iterator aoi2 = ao2_iterator_init(class->obj_container, 0);
                                while ((current = ao2_iterator_next(&aoi2))) {
-                                       ast_cli(a->fd, "  Pooled: No\n  Connected: %s\n", current->up && ast_odbc_sanity_check(current) ? "Yes" : "No");
+                                       ast_cli(a->fd, "  Pooled: No\n  Connected: %s\n", current->used ? "In use" :
+                                               current->up && ast_odbc_sanity_check(current) ? "Yes" : "No");
                                        ao2_ref(current, -1);
                                }
+                               ao2_iterator_destroy(&aoi2);
                        }
                        ast_cli(a->fd, "\n");
                }
                ao2_ref(class, -1);
        }
+       ao2_iterator_destroy(&aoi);
 
        return CLI_SUCCESS;
 }
@@ -625,8 +1041,9 @@ static int odbc_register_class(struct odbc_class *class, int preconnect)
                if (preconnect) {
                        /* Request and release builds a connection */
                        obj = ast_odbc_request_obj(class->name, 0);
-                       if (obj)
+                       if (obj) {
                                ast_odbc_release_obj(obj);
+                       }
                }
 
                return 0;
@@ -636,153 +1053,466 @@ static int odbc_register_class(struct odbc_class *class, int preconnect)
        }
 }
 
-void ast_odbc_release_obj(struct odbc_obj *obj)
+static void odbc_release_obj2(struct odbc_obj *obj, struct odbc_txn_frame *tx)
 {
-       /* For pooled connections, this frees the connection to be
-        * reused.  For non-pooled connections, it does nothing. */
-       obj->used = 0;
+       SQLINTEGER nativeerror=0, numfields=0;
+       SQLSMALLINT diagbytes=0, i;
+       unsigned char state[10], diagnostic[256];
+
+       ast_debug(2, "odbc_release_obj2(%p) called (obj->txf = %p)\n", obj, obj->txf);
+       if (tx) {
+               ast_debug(1, "called on a transactional handle with %s\n", tx->forcecommit ? "COMMIT" : "ROLLBACK");
+               if (SQLEndTran(SQL_HANDLE_DBC, obj->con, tx->forcecommit ? SQL_COMMIT : SQL_ROLLBACK) == SQL_ERROR) {
+                       /* Handle possible transaction commit failure */
+                       SQLGetDiagField(SQL_HANDLE_DBC, obj->con, 1, SQL_DIAG_NUMBER, &numfields, SQL_IS_INTEGER, &diagbytes);
+                       for (i = 0; i < numfields; i++) {
+                               SQLGetDiagRec(SQL_HANDLE_DBC, obj->con, i + 1, state, &nativeerror, diagnostic, sizeof(diagnostic), &diagbytes);
+                               ast_log(LOG_WARNING, "SQLEndTran returned an error: %s: %s\n", state, diagnostic);
+                               if (!strcmp((char *)state, "25S02") || !strcmp((char *)state, "08007")) {
+                                       /* These codes mean that a commit failed and a transaction
+                                        * is still active. We must rollback, or things will get
+                                        * very, very weird for anybody using the handle next. */
+                                       SQLEndTran(SQL_HANDLE_DBC, obj->con, SQL_ROLLBACK);
+                               }
+                               if (i > 10) {
+                                       ast_log(LOG_WARNING, "Oh, that was good.  There are really %d diagnostics?\n", (int)numfields);
+                                       break;
+                               }
+                       }
+               }
+
+               /* Transaction is done, reset autocommit */
+               if (SQLSetConnectAttr(obj->con, SQL_ATTR_AUTOCOMMIT, (void *)SQL_AUTOCOMMIT_ON, 0) == SQL_ERROR) {
+                       SQLGetDiagField(SQL_HANDLE_DBC, obj->con, 1, SQL_DIAG_NUMBER, &numfields, SQL_IS_INTEGER, &diagbytes);
+                       for (i = 0; i < numfields; i++) {
+                               SQLGetDiagRec(SQL_HANDLE_DBC, obj->con, i + 1, state, &nativeerror, diagnostic, sizeof(diagnostic), &diagbytes);
+                               ast_log(LOG_WARNING, "SetConnectAttr (Autocommit) returned an error: %s: %s\n", state, diagnostic);
+                               if (i > 10) {
+                                       ast_log(LOG_WARNING, "Oh, that was good.  There are really %d diagnostics?\n", (int)numfields);
+                                       break;
+                               }
+                       }
+               }
+       }
+
 #ifdef DEBUG_THREADS
        obj->file[0] = '\0';
        obj->function[0] = '\0';
        obj->lineno = 0;
 #endif
+
+       /* For pooled connections, this frees the connection to be
+        * reused.  For non-pooled connections, it does nothing. */
+       obj->used = 0;
+       if (obj->txf) {
+               /* Prevent recursion -- transaction is already closed out. */
+               obj->txf->obj = NULL;
+               obj->txf = release_transaction(obj->txf);
+       }
        ao2_ref(obj, -1);
 }
 
+void ast_odbc_release_obj(struct odbc_obj *obj)
+{
+       struct odbc_txn_frame *tx = find_transaction(NULL, obj, NULL, 0);
+       odbc_release_obj2(obj, tx);
+}
+
 int ast_odbc_backslash_is_escape(struct odbc_obj *obj)
 {
        return obj->parent->backslash_is_escape;
 }
 
-#ifdef DEBUG_THREADS
-struct odbc_obj *_ast_odbc_request_obj(const char *name, int check, const char *file, const char *function, int lineno)
-#else
-struct odbc_obj *ast_odbc_request_obj(const char *name, int check)
-#endif
+static int commit_exec(struct ast_channel *chan, const char *data)
 {
-       struct odbc_obj *obj = NULL;
-       struct odbc_class *class;
-       struct ao2_iterator aoi = ao2_iterator_init(class_container, 0);
+       struct odbc_txn_frame *tx;
+       SQLINTEGER nativeerror=0, numfields=0;
+       SQLSMALLINT diagbytes=0, i;
+       unsigned char state[10], diagnostic[256];
 
-       while ((class = ao2_iterator_next(&aoi))) {
-               if (!strcmp(class->name, name) && !class->delme) {
-                       break;
+       if (ast_strlen_zero(data)) {
+               tx = find_transaction(chan, NULL, NULL, 1);
+       } else {
+               tx = find_transaction(chan, NULL, data, 0);
+       }
+
+       pbx_builtin_setvar_helper(chan, "COMMIT_RESULT", "OK");
+
+       if (tx) {
+               if (SQLEndTran(SQL_HANDLE_DBC, tx->obj->con, SQL_COMMIT) == SQL_ERROR) {
+                       struct ast_str *errors = ast_str_thread_get(&errors_buf, 16);
+                       ast_str_reset(errors);
+
+                       /* Handle possible transaction commit failure */
+                       SQLGetDiagField(SQL_HANDLE_DBC, tx->obj->con, 1, SQL_DIAG_NUMBER, &numfields, SQL_IS_INTEGER, &diagbytes);
+                       for (i = 0; i < numfields; i++) {
+                               SQLGetDiagRec(SQL_HANDLE_DBC, tx->obj->con, i + 1, state, &nativeerror, diagnostic, sizeof(diagnostic), &diagbytes);
+                               ast_str_append(&errors, 0, "%s%s", ast_str_strlen(errors) ? "," : "", state);
+                               ast_log(LOG_WARNING, "SQLEndTran returned an error: %s: %s\n", state, diagnostic);
+                               if (i > 10) {
+                                       ast_log(LOG_WARNING, "Oh, that was good.  There are really %d diagnostics?\n", (int)numfields);
+                                       break;
+                               }
+                       }
+                       pbx_builtin_setvar_helper(chan, "COMMIT_RESULT", ast_str_buffer(errors));
                }
-               ao2_ref(class, -1);
        }
+       return 0;
+}
 
-       if (!class)
+static int rollback_exec(struct ast_channel *chan, const char *data)
+{
+       struct odbc_txn_frame *tx;
+       SQLINTEGER nativeerror=0, numfields=0;
+       SQLSMALLINT diagbytes=0, i;
+       unsigned char state[10], diagnostic[256];
+
+       if (ast_strlen_zero(data)) {
+               tx = find_transaction(chan, NULL, NULL, 1);
+       } else {
+               tx = find_transaction(chan, NULL, data, 0);
+       }
+
+       pbx_builtin_setvar_helper(chan, "ROLLBACK_RESULT", "OK");
+
+       if (tx) {
+               if (SQLEndTran(SQL_HANDLE_DBC, tx->obj->con, SQL_ROLLBACK) == SQL_ERROR) {
+                       struct ast_str *errors = ast_str_thread_get(&errors_buf, 16);
+                       ast_str_reset(errors);
+
+                       /* Handle possible transaction commit failure */
+                       SQLGetDiagField(SQL_HANDLE_DBC, tx->obj->con, 1, SQL_DIAG_NUMBER, &numfields, SQL_IS_INTEGER, &diagbytes);
+                       for (i = 0; i < numfields; i++) {
+                               SQLGetDiagRec(SQL_HANDLE_DBC, tx->obj->con, i + 1, state, &nativeerror, diagnostic, sizeof(diagnostic), &diagbytes);
+                               ast_str_append(&errors, 0, "%s%s", ast_str_strlen(errors) ? "," : "", state);
+                               ast_log(LOG_WARNING, "SQLEndTran returned an error: %s: %s\n", state, diagnostic);
+                               if (i > 10) {
+                                       ast_log(LOG_WARNING, "Oh, that was good.  There are really %d diagnostics?\n", (int)numfields);
+                                       break;
+                               }
+                       }
+                       pbx_builtin_setvar_helper(chan, "ROLLBACK_RESULT", ast_str_buffer(errors));
+               }
+       }
+       return 0;
+}
+
+static int aoro2_class_cb(void *obj, void *arg, int flags)
+{
+       struct odbc_class *class = obj;
+       char *name = arg;
+       if (!strcmp(class->name, name) && !class->delme) {
+               return CMP_MATCH | CMP_STOP;
+       }
+       return 0;
+}
+
+#define USE_TX (void *)(long)1
+#define NO_TX  (void *)(long)2
+#define EOR_TX (void *)(long)3
+
+static int aoro2_obj_cb(void *vobj, void *arg, int flags)
+{
+       struct odbc_obj *obj = vobj;
+       ao2_lock(obj);
+       if ((arg == NO_TX && !obj->tx) || (arg == EOR_TX && !obj->used) || (arg == USE_TX && obj->tx && !obj->used)) {
+               obj->used = 1;
+               ao2_unlock(obj);
+               return CMP_MATCH | CMP_STOP;
+       }
+       ao2_unlock(obj);
+       return 0;
+}
+
+/* This function should only be called for shared connections. Otherwise, the lack of
+ * setting vobj->used breaks EOR_TX searching. For nonshared connections, use
+ * aoro2_obj_cb instead. */
+static int aoro2_obj_notx_cb(void *vobj, void *arg, int flags)
+{
+       struct odbc_obj *obj = vobj;
+       if (!obj->tx) {
+               return CMP_MATCH | CMP_STOP;
+       }
+       return 0;
+}
+
+struct odbc_obj *_ast_odbc_request_obj2(const char *name, struct ast_flags flags, const char *file, const char *function, int lineno)
+{
+       struct odbc_obj *obj = NULL;
+       struct odbc_class *class;
+       SQLINTEGER nativeerror=0, numfields=0;
+       SQLSMALLINT diagbytes=0, i;
+       unsigned char state[10], diagnostic[256];
+
+       if (!(class = ao2_callback(class_container, 0, aoro2_class_cb, (char *) name))) {
+               ast_debug(1, "Class '%s' not found!\n", name);
                return NULL;
+       }
+
+       ast_assert(ao2_ref(class, 0) > 1);
 
        if (class->haspool) {
                /* Recycle connections before building another */
-               aoi = ao2_iterator_init(class->obj_container, 0);
-               while ((obj = ao2_iterator_next(&aoi))) {
-                       if (! obj->used) {
-                               ast_mutex_lock(&obj->lock);
+               obj = ao2_callback(class->obj_container, 0, aoro2_obj_cb, EOR_TX);
+
+               if (obj) {
+                       ast_assert(ao2_ref(obj, 0) > 1);
+               }
+               if (!obj && (ast_atomic_fetchadd_int(&class->count, +1) < class->limit) &&
+                               (time(NULL) > class->last_negative_connect.tv_sec + class->negative_connection_cache.tv_sec)) {
+                       obj = ao2_alloc(sizeof(*obj), odbc_obj_destructor);
+                       if (!obj) {
+                               class->count--;
+                               ao2_ref(class, -1);
+                               ast_debug(3, "Unable to allocate object\n");
+                               ast_atomic_fetchadd_int(&class->count, -1);
+                               return NULL;
+                       }
+                       ast_assert(ao2_ref(obj, 0) == 1);
+                       /* obj inherits the outstanding reference to class */
+                       obj->parent = class;
+                       class = NULL;
+                       if (odbc_obj_connect(obj) == ODBC_FAIL) {
+                               ast_log(LOG_WARNING, "Failed to connect to %s\n", name);
+                               ast_assert(ao2_ref(obj->parent, 0) > 0);
+                               /* Because it was never within the container, we have to manually decrement the count here */
+                               ast_atomic_fetchadd_int(&obj->parent->count, -1);
+                               ao2_ref(obj, -1);
+                               obj = NULL;
+                       } else {
                                obj->used = 1;
-                               ast_mutex_unlock(&obj->lock);
-                               break;
+                               ao2_link(obj->parent->obj_container, obj);
                        }
-                       ao2_ref(obj, -1);
+               } else {
+                       /* If construction fails due to the limit (or negative timecache), reverse our increment. */
+                       if (!obj) {
+                               ast_atomic_fetchadd_int(&class->count, -1);
+                       }
+                       /* Object is not constructed, so delete outstanding reference to class. */
+                       ao2_ref(class, -1);
+                       class = NULL;
                }
 
-               if (!obj && (class->count < class->limit)) {
-                       class->count++;
+               if (!obj) {
+                       return NULL;
+               }
+
+               ao2_lock(obj);
+
+               if (ast_test_flag(&flags, RES_ODBC_INDEPENDENT_CONNECTION)) {
+                       /* Ensure this connection has autocommit turned off. */
+                       if (SQLSetConnectAttr(obj->con, SQL_ATTR_AUTOCOMMIT, (void *)SQL_AUTOCOMMIT_OFF, 0) == SQL_ERROR) {
+                               SQLGetDiagField(SQL_HANDLE_DBC, obj->con, 1, SQL_DIAG_NUMBER, &numfields, SQL_IS_INTEGER, &diagbytes);
+                               for (i = 0; i < numfields; i++) {
+                                       SQLGetDiagRec(SQL_HANDLE_DBC, obj->con, i + 1, state, &nativeerror, diagnostic, sizeof(diagnostic), &diagbytes);
+                                       ast_log(LOG_WARNING, "SQLSetConnectAttr (Autocommit) returned an error: %s: %s\n", state, diagnostic);
+                                       if (i > 10) {
+                                               ast_log(LOG_WARNING, "Oh, that was good.  There are really %d diagnostics?\n", (int)numfields);
+                                               break;
+                                       }
+                               }
+                       }
+               }
+       } else if (ast_test_flag(&flags, RES_ODBC_INDEPENDENT_CONNECTION)) {
+               /* Non-pooled connections -- but must use a separate connection handle */
+               if (!(obj = ao2_callback(class->obj_container, 0, aoro2_obj_cb, USE_TX))) {
+                       ast_debug(1, "Object not found\n");
                        obj = ao2_alloc(sizeof(*obj), odbc_obj_destructor);
                        if (!obj) {
                                ao2_ref(class, -1);
+                               ast_debug(3, "Unable to allocate object\n");
                                return NULL;
                        }
-                       ast_mutex_init(&obj->lock);
                        /* obj inherits the outstanding reference to class */
                        obj->parent = class;
+                       class = NULL;
                        if (odbc_obj_connect(obj) == ODBC_FAIL) {
                                ast_log(LOG_WARNING, "Failed to connect to %s\n", name);
                                ao2_ref(obj, -1);
                                obj = NULL;
-                               class->count--;
                        } else {
                                obj->used = 1;
-                               ao2_link(class->obj_container, obj);
+                               ao2_link(obj->parent->obj_container, obj);
+                               ast_atomic_fetchadd_int(&obj->parent->count, +1);
                        }
                }
-       } else {
-               /* Non-pooled connection: multiple modules can use the same connection. */
-               aoi = ao2_iterator_init(class->obj_container, 0);
-               while ((obj = ao2_iterator_next(&aoi))) {
-                       /* Non-pooled connection: if there is an entry, return it */
-                       break;
-               }
 
                if (!obj) {
+                       return NULL;
+               }
+
+               ao2_lock(obj);
+
+               if (SQLSetConnectAttr(obj->con, SQL_ATTR_AUTOCOMMIT, (void *)SQL_AUTOCOMMIT_OFF, 0) == SQL_ERROR) {
+                       SQLGetDiagField(SQL_HANDLE_DBC, obj->con, 1, SQL_DIAG_NUMBER, &numfields, SQL_IS_INTEGER, &diagbytes);
+                       for (i = 0; i < numfields; i++) {
+                               SQLGetDiagRec(SQL_HANDLE_DBC, obj->con, i + 1, state, &nativeerror, diagnostic, sizeof(diagnostic), &diagbytes);
+                               ast_log(LOG_WARNING, "SetConnectAttr (Autocommit) returned an error: %s: %s\n", state, diagnostic);
+                               if (i > 10) {
+                                       ast_log(LOG_WARNING, "Oh, that was good.  There are really %d diagnostics?\n", (int)numfields);
+                                       break;
+                               }
+                       }
+               }
+       } else {
+               /* Non-pooled connection: multiple modules can use the same connection. */
+               if ((obj = ao2_callback(class->obj_container, 0, aoro2_obj_notx_cb, NO_TX))) {
+                       /* Object is not constructed, so delete outstanding reference to class. */
+                       ast_assert(ao2_ref(class, 0) > 1);
+                       ao2_ref(class, -1);
+                       class = NULL;
+               } else {
                        /* No entry: build one */
-                       obj = ao2_alloc(sizeof(*obj), odbc_obj_destructor);
-                       if (!obj) {
+                       if (!(obj = ao2_alloc(sizeof(*obj), odbc_obj_destructor))) {
+                               ast_assert(ao2_ref(class, 0) > 1);
                                ao2_ref(class, -1);
+                               ast_debug(3, "Unable to allocate object\n");
                                return NULL;
                        }
-                       ast_mutex_init(&obj->lock);
                        /* obj inherits the outstanding reference to class */
                        obj->parent = class;
+                       class = NULL;
                        if (odbc_obj_connect(obj) == ODBC_FAIL) {
                                ast_log(LOG_WARNING, "Failed to connect to %s\n", name);
                                ao2_ref(obj, -1);
                                obj = NULL;
                        } else {
-                               ao2_link(class->obj_container, obj);
+                               ao2_link(obj->parent->obj_container, obj);
+                               ast_assert(ao2_ref(obj, 0) > 1);
+                       }
+               }
+
+               if (!obj) {
+                       return NULL;
+               }
+
+               ao2_lock(obj);
+
+               if (SQLSetConnectAttr(obj->con, SQL_ATTR_AUTOCOMMIT, (void *)SQL_AUTOCOMMIT_ON, 0) == SQL_ERROR) {
+                       SQLGetDiagField(SQL_HANDLE_DBC, obj->con, 1, SQL_DIAG_NUMBER, &numfields, SQL_IS_INTEGER, &diagbytes);
+                       for (i = 0; i < numfields; i++) {
+                               SQLGetDiagRec(SQL_HANDLE_DBC, obj->con, i + 1, state, &nativeerror, diagnostic, sizeof(diagnostic), &diagbytes);
+                               ast_log(LOG_WARNING, "SetConnectAttr (Autocommit) returned an error: %s: %s\n", state, diagnostic);
+                               if (i > 10) {
+                                       ast_log(LOG_WARNING, "Oh, that was good.  There are really %d diagnostics?\n", (int)numfields);
+                                       break;
+                               }
                        }
                }
        }
 
-       if (obj && check) {
+       ast_assert(obj != NULL);
+
+       /* Set the isolation property */
+       if (SQLSetConnectAttr(obj->con, SQL_ATTR_TXN_ISOLATION, (void *)(long)obj->parent->isolation, 0) == SQL_ERROR) {
+               SQLGetDiagField(SQL_HANDLE_DBC, obj->con, 1, SQL_DIAG_NUMBER, &numfields, SQL_IS_INTEGER, &diagbytes);
+               for (i = 0; i < numfields; i++) {
+                       SQLGetDiagRec(SQL_HANDLE_DBC, obj->con, i + 1, state, &nativeerror, diagnostic, sizeof(diagnostic), &diagbytes);
+                       ast_log(LOG_WARNING, "SetConnectAttr (Txn isolation) returned an error: %s: %s\n", state, diagnostic);
+                       if (i > 10) {
+                               ast_log(LOG_WARNING, "Oh, that was good.  There are really %d diagnostics?\n", (int)numfields);
+                               break;
+                       }
+               }
+       }
+
+       if (ast_test_flag(&flags, RES_ODBC_CONNECTED) && !obj->up) {
+               /* Check if this connection qualifies for reconnection, with negative connection cache time */
+               if (time(NULL) > obj->parent->last_negative_connect.tv_sec + obj->parent->negative_connection_cache.tv_sec) {
+                       odbc_obj_connect(obj);
+               }
+       } else if (ast_test_flag(&flags, RES_ODBC_SANITY_CHECK)) {
                ast_odbc_sanity_check(obj);
-       } else if (obj && obj->parent->idlecheck > 0 && ast_tvdiff_sec(ast_tvnow(), obj->last_used) > obj->parent->idlecheck)
+       } else if (obj->parent->idlecheck > 0 && ast_tvdiff_sec(ast_tvnow(), obj->last_used) > obj->parent->idlecheck) {
                odbc_obj_connect(obj);
+       }
 
 #ifdef DEBUG_THREADS
-       if (obj) {
-               ast_copy_string(obj->file, file, sizeof(obj->file));
-               ast_copy_string(obj->function, function, sizeof(obj->function));
-               obj->lineno = lineno;
-       }
+       ast_copy_string(obj->file, file, sizeof(obj->file));
+       ast_copy_string(obj->function, function, sizeof(obj->function));
+       obj->lineno = lineno;
 #endif
 
+       /* We had it locked because of the obj_connects we see here. */
+       ao2_unlock(obj);
+
+       ast_assert(class == NULL);
+
+       ast_assert(ao2_ref(obj, 0) > 1);
        return obj;
 }
 
+struct odbc_obj *_ast_odbc_request_obj(const char *name, int check, const char *file, const char *function, int lineno)
+{
+       struct ast_flags flags = { check ? RES_ODBC_SANITY_CHECK : 0 };
+       return _ast_odbc_request_obj2(name, flags, file, function, lineno);
+}
+
+struct odbc_obj *ast_odbc_retrieve_transaction_obj(struct ast_channel *chan, const char *objname)
+{
+       struct ast_datastore *txn_store;
+       AST_LIST_HEAD(, odbc_txn_frame) *oldlist;
+       struct odbc_txn_frame *txn = NULL;
+
+       if (!chan) {
+               /* No channel == no transaction */
+               return NULL;
+       }
+
+       ast_channel_lock(chan);
+       if ((txn_store = ast_channel_datastore_find(chan, &txn_info, NULL))) {
+               oldlist = txn_store->data;
+       } else {
+               ast_channel_unlock(chan);
+               return NULL;
+       }
+
+       AST_LIST_LOCK(oldlist);
+       ast_channel_unlock(chan);
+
+       AST_LIST_TRAVERSE(oldlist, txn, list) {
+               if (txn->obj && txn->obj->parent && !strcmp(txn->obj->parent->name, objname)) {
+                       AST_LIST_UNLOCK(oldlist);
+                       return txn->obj;
+               }
+       }
+       AST_LIST_UNLOCK(oldlist);
+       return NULL;
+}
+
 static odbc_status odbc_obj_disconnect(struct odbc_obj *obj)
 {
        int res;
        SQLINTEGER err;
        short int mlen;
-       unsigned char msg[200], stat[10];
+       unsigned char msg[200], state[10];
+       SQLHDBC con;
 
        /* Nothing to disconnect */
        if (!obj->con) {
                return ODBC_SUCCESS;
        }
 
-       ast_mutex_lock(&obj->lock);
-
-       res = SQLDisconnect(obj->con);
+       con = obj->con;
+       obj->con = NULL;
+       res = SQLDisconnect(con);
 
-       if (res == SQL_SUCCESS || res == SQL_SUCCESS_WITH_INFO) {
-               ast_log(LOG_DEBUG, "Disconnected %d from %s [%s]\n", res, obj->parent->name, obj->parent->dsn);
-       } else {
-               ast_log(LOG_DEBUG, "res_odbc: %s [%s] already disconnected\n", obj->parent->name, obj->parent->dsn);
+       if (obj->parent) {
+               if (res == SQL_SUCCESS || res == SQL_SUCCESS_WITH_INFO) {
+                       ast_debug(1, "Disconnected %d from %s [%s]\n", res, obj->parent->name, obj->parent->dsn);
+               } else {
+                       ast_debug(1, "res_odbc: %s [%s] already disconnected\n", obj->parent->name, obj->parent->dsn);
+               }
        }
 
-       if ((res = SQLFreeHandle(SQL_HANDLE_DBC, obj->con) == SQL_SUCCESS)) {
-               obj->con = NULL;
-               ast_log(LOG_DEBUG, "Database handle deallocated\n");
+       if ((res = SQLFreeHandle(SQL_HANDLE_DBC, con)) == SQL_SUCCESS) {
+               ast_debug(1, "Database handle %p deallocated\n", con);
        } else {
-               SQLGetDiagRec(SQL_HANDLE_DBC, obj->con, 1, stat, &err, msg, 100, &mlen);
-               ast_log(LOG_WARNING, "Unable to deallocate database handle? %d errno=%d %s\n", res, (int)err, msg);
+               SQLGetDiagRec(SQL_HANDLE_DBC, con, 1, state, &err, msg, 100, &mlen);
+               ast_log(LOG_WARNING, "Unable to deallocate database handle %p? %d errno=%d %s\n", con, res, (int)err, msg);
        }
 
        obj->up = 0;
-       ast_mutex_unlock(&obj->lock);
        return ODBC_SUCCESS;
 }
 
@@ -796,38 +1526,43 @@ static odbc_status odbc_obj_connect(struct odbc_obj *obj)
        SQLINTEGER enable = 1;
        char *tracefile = "/tmp/odbc.trace";
 #endif
-       ast_mutex_lock(&obj->lock);
+       SQLHDBC con;
 
        if (obj->up) {
                odbc_obj_disconnect(obj);
                ast_log(LOG_NOTICE, "Re-connecting %s\n", obj->parent->name);
        } else {
+               ast_assert(obj->con == NULL);
                ast_log(LOG_NOTICE, "Connecting %s\n", obj->parent->name);
        }
 
-       res = SQLAllocHandle(SQL_HANDLE_DBC, obj->parent->env, &obj->con);
+       res = SQLAllocHandle(SQL_HANDLE_DBC, obj->parent->env, &con);
 
        if ((res != SQL_SUCCESS) && (res != SQL_SUCCESS_WITH_INFO)) {
                ast_log(LOG_WARNING, "res_odbc: Error AllocHDB %d\n", res);
-               ast_mutex_unlock(&obj->lock);
+               obj->parent->last_negative_connect = ast_tvnow();
                return ODBC_FAIL;
        }
-       SQLSetConnectAttr(obj->con, SQL_LOGIN_TIMEOUT, (SQLPOINTER *) 10, 0);
-       SQLSetConnectAttr(obj->con, SQL_ATTR_CONNECTION_TIMEOUT, (SQLPOINTER *) 10, 0);
+       SQLSetConnectAttr(con, SQL_LOGIN_TIMEOUT, (SQLPOINTER *)(long) obj->parent->conntimeout, 0);
+       SQLSetConnectAttr(con, SQL_ATTR_CONNECTION_TIMEOUT, (SQLPOINTER *)(long) obj->parent->conntimeout, 0);
 #ifdef NEEDTRACE
-       SQLSetConnectAttr(obj->con, SQL_ATTR_TRACE, &enable, SQL_IS_INTEGER);
-       SQLSetConnectAttr(obj->con, SQL_ATTR_TRACEFILE, tracefile, strlen(tracefile));
+       SQLSetConnectAttr(con, SQL_ATTR_TRACE, &enable, SQL_IS_INTEGER);
+       SQLSetConnectAttr(con, SQL_ATTR_TRACEFILE, tracefile, strlen(tracefile));
 #endif
 
-       res = SQLConnect(obj->con,
+       res = SQLConnect(con,
                   (SQLCHAR *) obj->parent->dsn, SQL_NTS,
                   (SQLCHAR *) obj->parent->username, SQL_NTS,
                   (SQLCHAR *) obj->parent->password, SQL_NTS);
 
        if ((res != SQL_SUCCESS) && (res != SQL_SUCCESS_WITH_INFO)) {
-               SQLGetDiagRec(SQL_HANDLE_DBC, obj->con, 1, state, &err, msg, 100, &mlen);
-               ast_mutex_unlock(&obj->lock);
+               SQLGetDiagRec(SQL_HANDLE_DBC, con, 1, state, &err, msg, 100, &mlen);
+               obj->parent->last_negative_connect = ast_tvnow();
                ast_log(LOG_WARNING, "res_odbc: Error SQLConnect=%d errno=%d %s\n", res, (int)err, msg);
+               if ((res = SQLFreeHandle(SQL_HANDLE_DBC, con)) != SQL_SUCCESS) {
+                       SQLGetDiagRec(SQL_HANDLE_DBC, con, 1, state, &err, msg, 100, &mlen);
+                       ast_log(LOG_WARNING, "Unable to deallocate database handle %p? %d errno=%d %s\n", con, res, (int)err, msg);
+               }
                return ODBC_FAIL;
        } else {
                ast_log(LOG_NOTICE, "res_odbc: Connected to %s [%s]\n", obj->parent->name, obj->parent->dsn);
@@ -835,10 +1570,240 @@ static odbc_status odbc_obj_connect(struct odbc_obj *obj)
                obj->last_used = ast_tvnow();
        }
 
-       ast_mutex_unlock(&obj->lock);
+       obj->con = con;
        return ODBC_SUCCESS;
 }
 
+static int acf_transaction_read(struct ast_channel *chan, const char *cmd, char *data, char *buf, size_t len)
+{
+       AST_DECLARE_APP_ARGS(args,
+               AST_APP_ARG(property);
+               AST_APP_ARG(opt);
+       );
+       struct odbc_txn_frame *tx;
+
+       AST_STANDARD_APP_ARGS(args, data);
+       if (strcasecmp(args.property, "transaction") == 0) {
+               if ((tx = find_transaction(chan, NULL, NULL, 1))) {
+                       ast_copy_string(buf, tx->name, len);
+                       return 0;
+               }
+       } else if (strcasecmp(args.property, "isolation") == 0) {
+               if (!ast_strlen_zero(args.opt)) {
+                       tx = find_transaction(chan, NULL, args.opt, 0);
+               } else {
+                       tx = find_transaction(chan, NULL, NULL, 1);
+               }
+               if (tx) {
+                       ast_copy_string(buf, isolation2text(tx->isolation), len);
+                       return 0;
+               }
+       } else if (strcasecmp(args.property, "forcecommit") == 0) {
+               if (!ast_strlen_zero(args.opt)) {
+                       tx = find_transaction(chan, NULL, args.opt, 0);
+               } else {
+                       tx = find_transaction(chan, NULL, NULL, 1);
+               }
+               if (tx) {
+                       ast_copy_string(buf, tx->forcecommit ? "1" : "0", len);
+                       return 0;
+               }
+       }
+       return -1;
+}
+
+static int acf_transaction_write(struct ast_channel *chan, const char *cmd, char *s, const char *value)
+{
+       AST_DECLARE_APP_ARGS(args,
+               AST_APP_ARG(property);
+               AST_APP_ARG(opt);
+       );
+       struct odbc_txn_frame *tx;
+       SQLINTEGER nativeerror=0, numfields=0;
+       SQLSMALLINT diagbytes=0, i;
+       unsigned char state[10], diagnostic[256];
+
+       AST_STANDARD_APP_ARGS(args, s);
+       if (strcasecmp(args.property, "transaction") == 0) {
+               /* Set active transaction */
+               struct odbc_obj *obj;
+               if ((tx = find_transaction(chan, NULL, value, 0))) {
+                       mark_transaction_active(chan, tx);
+               } else {
+                       /* No such transaction, create one */
+                       struct ast_flags flags = { RES_ODBC_INDEPENDENT_CONNECTION };
+                       if (ast_strlen_zero(args.opt) || !(obj = ast_odbc_request_obj2(args.opt, flags))) {
+                               ast_log(LOG_ERROR, "Could not create transaction: invalid database specification '%s'\n", S_OR(args.opt, ""));
+                               pbx_builtin_setvar_helper(chan, "ODBC_RESULT", "INVALID_DB");
+                               return -1;
+                       }
+                       if (!find_transaction(chan, obj, value, 0)) {
+                               pbx_builtin_setvar_helper(chan, "ODBC_RESULT", "FAILED_TO_CREATE");
+                               return -1;
+                       }
+                       obj->tx = 1;
+               }
+               pbx_builtin_setvar_helper(chan, "ODBC_RESULT", "OK");
+               return 0;
+       } else if (strcasecmp(args.property, "forcecommit") == 0) {
+               /* Set what happens when an uncommitted transaction ends without explicit Commit or Rollback */
+               if (ast_strlen_zero(args.opt)) {
+                       tx = find_transaction(chan, NULL, NULL, 1);
+               } else {
+                       tx = find_transaction(chan, NULL, args.opt, 0);
+               }
+               if (!tx) {
+                       pbx_builtin_setvar_helper(chan, "ODBC_RESULT", "FAILED_TO_CREATE");
+                       return -1;
+               }
+               if (ast_true(value)) {
+                       tx->forcecommit = 1;
+               } else if (ast_false(value)) {
+                       tx->forcecommit = 0;
+               } else {
+                       ast_log(LOG_ERROR, "Invalid value for forcecommit: '%s'\n", S_OR(value, ""));
+                       pbx_builtin_setvar_helper(chan, "ODBC_RESULT", "INVALID_VALUE");
+                       return -1;
+               }
+
+               pbx_builtin_setvar_helper(chan, "ODBC_RESULT", "OK");
+               return 0;
+       } else if (strcasecmp(args.property, "isolation") == 0) {
+               /* How do uncommitted transactions affect reads? */
+               int isolation = text2isolation(value);
+               if (ast_strlen_zero(args.opt)) {
+                       tx = find_transaction(chan, NULL, NULL, 1);
+               } else {
+                       tx = find_transaction(chan, NULL, args.opt, 0);
+               }
+               if (!tx) {
+                       pbx_builtin_setvar_helper(chan, "ODBC_RESULT", "FAILED_TO_CREATE");
+                       return -1;
+               }
+               if (isolation == 0) {
+                       pbx_builtin_setvar_helper(chan, "ODBC_RESULT", "INVALID_VALUE");
+                       ast_log(LOG_ERROR, "Invalid isolation specification: '%s'\n", S_OR(value, ""));
+               } else if (SQLSetConnectAttr(tx->obj->con, SQL_ATTR_TXN_ISOLATION, (void *)(long)isolation, 0) == SQL_ERROR) {
+                       pbx_builtin_setvar_helper(chan, "ODBC_RESULT", "SQL_ERROR");
+                       SQLGetDiagField(SQL_HANDLE_DBC, tx->obj->con, 1, SQL_DIAG_NUMBER, &numfields, SQL_IS_INTEGER, &diagbytes);
+                       for (i = 0; i < numfields; i++) {
+                               SQLGetDiagRec(SQL_HANDLE_DBC, tx->obj->con, i + 1, state, &nativeerror, diagnostic, sizeof(diagnostic), &diagbytes);
+                               ast_log(LOG_WARNING, "SetConnectAttr (Txn isolation) returned an error: %s: %s\n", state, diagnostic);
+                               if (i > 10) {
+                                       ast_log(LOG_WARNING, "Oh, that was good.  There are really %d diagnostics?\n", (int)numfields);
+                                       break;
+                               }
+                       }
+               } else {
+                       pbx_builtin_setvar_helper(chan, "ODBC_RESULT", "OK");
+                       tx->isolation = isolation;
+               }
+               return 0;
+       } else {
+               ast_log(LOG_ERROR, "Unknown property: '%s'\n", args.property);
+               return -1;
+       }
+}
+
+static struct ast_custom_function odbc_function = {
+       .name = "ODBC",
+       .read = acf_transaction_read,
+       .write = acf_transaction_write,
+};
+
+static const char * const app_commit = "ODBC_Commit";
+static const char * const app_rollback = "ODBC_Rollback";
+
+/*!
+ * \internal
+ * \brief Implements the channels provider.
+ */
+static int data_odbc_provider_handler(const struct ast_data_search *search,
+               struct ast_data *root)
+{
+       struct ao2_iterator aoi, aoi2;
+       struct odbc_class *class;
+       struct odbc_obj *current;
+       struct ast_data *data_odbc_class, *data_odbc_connections, *data_odbc_connection;
+       struct ast_data *enum_node;
+       int count;
+
+       aoi = ao2_iterator_init(class_container, 0);
+       while ((class = ao2_iterator_next(&aoi))) {
+               data_odbc_class = ast_data_add_node(root, "class");
+               if (!data_odbc_class) {
+                       ao2_ref(class, -1);
+                       continue;
+               }
+
+               ast_data_add_structure(odbc_class, data_odbc_class, class);
+
+               if (!ao2_container_count(class->obj_container)) {
+                       ao2_ref(class, -1);
+                       continue;
+               }
+
+               data_odbc_connections = ast_data_add_node(data_odbc_class, "connections");
+               if (!data_odbc_connections) {
+                       ao2_ref(class, -1);
+                       continue;
+               }
+
+               ast_data_add_bool(data_odbc_class, "shared", !class->haspool);
+               /* isolation */
+               enum_node = ast_data_add_node(data_odbc_class, "isolation");
+               if (!enum_node) {
+                       ao2_ref(class, -1);
+                       continue;
+               }
+               ast_data_add_int(enum_node, "value", class->isolation);
+               ast_data_add_str(enum_node, "text", isolation2text(class->isolation));
+
+               count = 0;
+               aoi2 = ao2_iterator_init(class->obj_container, 0);
+               while ((current = ao2_iterator_next(&aoi2))) {
+                       data_odbc_connection = ast_data_add_node(data_odbc_connections, "connection");
+                       if (!data_odbc_connection) {
+                               ao2_ref(current, -1);
+                               continue;
+                       }
+
+                       ao2_lock(current);
+                       ast_data_add_str(data_odbc_connection, "status", current->used ? "in use" :
+                                       current->up && ast_odbc_sanity_check(current) ? "connected" : "disconnected");
+                       ast_data_add_bool(data_odbc_connection, "transactional", current->tx);
+                       ao2_unlock(current);
+
+                       if (class->haspool) {
+                               ast_data_add_int(data_odbc_connection, "number", ++count);
+                       }
+
+                       ao2_ref(current, -1);
+               }
+               ao2_iterator_destroy(&aoi2);
+               ao2_ref(class, -1);
+
+               if (!ast_data_search_match(search, data_odbc_class)) {
+                       ast_data_remove_node(root, data_odbc_class);
+               }
+       }
+       ao2_iterator_destroy(&aoi);
+       return 0;
+}
+
+/*!
+ * \internal
+ * \brief /asterisk/res/odbc/listprovider.
+ */
+static const struct ast_data_handler odbc_provider = {
+       .version = AST_DATA_HANDLER_VERSION,
+       .get = data_odbc_provider_handler
+};
+
+static const struct ast_data_entry odbc_providers[] = {
+       AST_DATA_ENTRY("/asterisk/res/odbc", &odbc_provider),
+};
+
 static int reload(void)
 {
        struct odbc_cache_tables *table;
@@ -851,6 +1816,7 @@ static int reload(void)
                class->delme = 1;
                ao2_ref(class, -1);
        }
+       ao2_iterator_destroy(&aoi);
 
        load_odbc_config();
 
@@ -890,6 +1856,7 @@ static int reload(void)
                                 * b) the object has already been destroyed.
                                 */
                        }
+                       ao2_iterator_destroy(&aoi2);
                        ao2_unlink(class_container, class); /* unlink C-ref from container (reference handled implicitly) */
                        /* At this point, either
                         * a) there's an outstanding O-ref, which holds an outstanding C-ref, or
@@ -899,6 +1866,7 @@ static int reload(void)
                }
                ao2_ref(class, -1); /* C-ref-- (by iterator) */
        }
+       ao2_iterator_destroy(&aoi);
 
        /* Empty the cache; it will get rebuilt the next time the tables are needed. */
        AST_RWLIST_WRLOCK(&odbc_tables);
@@ -916,19 +1884,34 @@ static int unload_module(void)
        return -1;
 }
 
+/*!
+ * \brief Load the module
+ *
+ * Module loading including tests for configuration or dependencies.
+ * This function can return AST_MODULE_LOAD_FAILURE, AST_MODULE_LOAD_DECLINE,
+ * or AST_MODULE_LOAD_SUCCESS. If a dependency or environment variable fails
+ * tests return AST_MODULE_LOAD_FAILURE. If the module can not load the 
+ * configuration file or other non-critical problem return 
+ * AST_MODULE_LOAD_DECLINE. On success return AST_MODULE_LOAD_SUCCESS.
+ */
 static int load_module(void)
 {
        if (!(class_container = ao2_container_alloc(1, null_hash_fn, ao2_match_by_addr)))
                return AST_MODULE_LOAD_DECLINE;
        if (load_odbc_config() == -1)
                return AST_MODULE_LOAD_DECLINE;
-       ast_cli_register_multiple(cli_odbc, sizeof(cli_odbc) / sizeof(struct ast_cli_entry));
+       ast_cli_register_multiple(cli_odbc, ARRAY_LEN(cli_odbc));
+       ast_data_register_multiple(odbc_providers, ARRAY_LEN(odbc_providers));
+       ast_register_application_xml(app_commit, commit_exec);
+       ast_register_application_xml(app_rollback, rollback_exec);
+       ast_custom_function_register(&odbc_function);
        ast_log(LOG_NOTICE, "res_odbc loaded.\n");
        return 0;
 }
 
-AST_MODULE_INFO(ASTERISK_GPL_KEY, AST_MODFLAG_GLOBAL_SYMBOLS, "ODBC resource",
+AST_MODULE_INFO(ASTERISK_GPL_KEY, AST_MODFLAG_GLOBAL_SYMBOLS | AST_MODFLAG_LOAD_ORDER, "ODBC resource",
                .load = load_module,
                .unload = unload_module,
                .reload = reload,
+               .load_pri = AST_MODPRI_REALTIME_DEPEND,
               );