func_odbc.c

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/*
 * Asterisk -- An open source telephony toolkit.
 *
 * Copyright (c) 2005, 2006 Tilghman Lesher
 * Copyright (c) 2008, 2009 Digium, Inc.
 *
 * Tilghman Lesher <func_odbc__200508@the-tilghman.com>
 *
 * See http://www.asterisk.org for more information about
 * the Asterisk project. Please do not directly contact
 * any of the maintainers of this project for assistance;
 * the project provides a web site, mailing lists and IRC
 * channels for your use.
 *
 * This program is free software, distributed under the terms of
 * the GNU General Public License Version 2. See the LICENSE file
 * at the top of the source tree.
 */
 
/*!
 * \file
 *
 * \brief ODBC lookups
 *
 * \author Tilghman Lesher <func_odbc__200508@the-tilghman.com>
 *
 * \ingroup functions
 */
 
/*** MODULEINFO
    <depend>res_odbc</depend>
    <depend>generic_odbc</depend>
    <support_level>core</support_level>
 ***/
 
#include "asterisk.h"
 
#include "asterisk/module.h"
#include "asterisk/file.h"
#include "asterisk/channel.h"
#include "asterisk/pbx.h"
#include "asterisk/config.h"
#include "asterisk/res_odbc.h"
#include "asterisk/res_odbc_transaction.h"
#include "asterisk/app.h"
#include "asterisk/cli.h"
#include "asterisk/strings.h"
 
/*** DOCUMENTATION
    <function name="ODBC_FETCH" language="en_US">
        <synopsis>
            Fetch a row from a multirow query.
        </synopsis>
        <syntax>
            <parameter name="result-id" required="true" />
        </syntax>
        <description>
            <para>For queries which are marked as mode=multirow, the original
            query returns a <replaceable>result-id</replaceable> from which results
            may be fetched.  This function implements the actual fetch of the results.</para>
            <para>This also sets <variable>ODBC_FETCH_STATUS</variable>.</para>
            <variablelist>
                <variable name="ODBC_FETCH_STATUS">
                    <value name="SUCESS">
                        If rows are available.
                    </value>
                    <value name="FAILURE">
                        If no rows are available.
                    </value>
                </variable>
            </variablelist>
        </description>
    </function>
    <application name="ODBCFinish" language="en_US">
        <synopsis>
            Clear the resultset of a sucessful multirow query.
        </synopsis>
        <syntax>
            <parameter name="result-id" required="true" />
        </syntax>
        <description>
            <para>For queries which are marked as mode=multirow, this will clear
            any remaining rows of the specified resultset.</para>
        </description>
    </application>
    <function name="SQL_ESC" language="en_US">
        <synopsis>
            Escapes single ticks for use in SQL statements.
        </synopsis>
        <syntax>
            <parameter name="string" required="true" />
        </syntax>
        <description>
            <para>Used in SQL templates to escape data which may contain single ticks
            <literal>'</literal> which are otherwise used to delimit data.</para>
            <example title="Escape example">
             SELECT foo FROM bar WHERE baz='${SQL_ESC(${ARG1})}'
            </example>
        </description>
    </function>
    <function name="SQL_ESC_BACKSLASHES" language="en_US">
        <synopsis>
            Escapes backslashes for use in SQL statements.
        </synopsis>
        <syntax>
            <parameter name="string" required="true" />
        </syntax>
        <description>
            <para>Used in SQL templates to escape data which may contain backslashes
            <literal></literal> which are otherwise used to escape data.</para>
            <example title="Escape with backslashes example">
            SELECT foo FROM bar WHERE baz='${SQL_ESC(${SQL_ESC_BACKSLASHES(${ARG1})})}'
            </example>
        </description>
    </function>
 ***/
 
static char *config = "func_odbc.conf";
 
#define DEFAULT_SINGLE_DB_CONNECTION 0
 
static int single_db_connection;
 
AST_RWLOCK_DEFINE_STATIC(single_db_connection_lock);
 
enum odbc_option_flags {
    OPT_ESCAPECOMMAS =  (1 << 0),
    OPT_MULTIROW     =  (1 << 1),
};
 
struct acf_odbc_query {
    AST_RWLIST_ENTRY(acf_odbc_query) list;
    char readhandle[5][30];
    char writehandle[5][30];
    char *sql_read;
    char *sql_write;
    char *sql_insert;
    unsigned int flags;
    int rowlimit;
    int minargs;
    struct ast_custom_function *acf;
};
 
static void odbc_datastore_free(void *data);
 
static const struct ast_datastore_info odbc_info = {
    .type = "FUNC_ODBC",
    .destroy = odbc_datastore_free,
};
 
/* For storing each result row */
struct odbc_datastore_row {
    AST_LIST_ENTRY(odbc_datastore_row) list;
    char data[0];
};
 
/* For storing each result set */
struct odbc_datastore {
    AST_LIST_HEAD(, odbc_datastore_row);
    char names[0];
};
 
/*! \brief Data source name
 *
 * This holds data that pertains to a DSN
 */
struct dsn {
    /*! A connection to the database */
    struct odbc_obj *connection;
    /*! The name of the DSN as defined in res_odbc.conf */
    char name[0];
};
 
#define DSN_BUCKETS 37
 
struct ao2_container *dsns;
 
static int dsn_hash(const void *obj, const int flags)
{
    const struct dsn *object;
    const char *key;
 
    switch (flags & OBJ_SEARCH_MASK) {
    case OBJ_SEARCH_KEY:
        key = obj;
        break;
    case OBJ_SEARCH_OBJECT:
        object = obj;
        key = object->name;
        break;
    default:
        ast_assert(0);
        return 0;
    }
    return ast_str_hash(key);
}
 
static int dsn_cmp(void *obj, void *arg, int flags)
{
    const struct dsn *object_left = obj;
    const struct dsn *object_right = arg;
    const char *right_key = arg;
    int cmp;
 
    switch (flags & OBJ_SEARCH_MASK) {
    case OBJ_SEARCH_OBJECT:
        right_key = object_right->name;
        /* Fall through */
    case OBJ_SEARCH_KEY:
        cmp = strcmp(object_left->name, right_key);
        break;
    case OBJ_SEARCH_PARTIAL_KEY:
        cmp = strncmp(object_left->name, right_key, strlen(right_key));
        break;
    default:
        cmp = 0;
        break;
    }
 
    if (cmp) {
        return 0;
    }
 
    return CMP_MATCH;
}
 
static void dsn_destructor(void *obj)
{
    struct dsn *dsn = obj;
 
    if (dsn->connection) {
        ast_odbc_release_obj(dsn->connection);
    }
}
 
/*!
 * \brief Create a DSN and connect to the database
 *
 * \param name The name of the DSN as found in res_odbc.conf
 * \retval NULL Fail
 * \retval non-NULL The newly-created structure
 */
static struct dsn *create_dsn(const char *name)
{
    struct dsn *dsn;
 
    if (!dsns) {
        return NULL;
    }
 
    dsn = ao2_alloc(sizeof(*dsn) + strlen(name) + 1, dsn_destructor);
    if (!dsn) {
        return NULL;
    }
 
    /* Safe */
    strcpy(dsn->name, name);
 
    dsn->connection = ast_odbc_request_obj(name, 0);
    if (!dsn->connection) {
        ao2_ref(dsn, -1);
        return NULL;
    }
 
    if (!ao2_link_flags(dsns, dsn, OBJ_NOLOCK)) {
        ao2_ref(dsn, -1);
        return NULL;
    }
 
    return dsn;
}
 
static SQLHSTMT silent_execute(struct odbc_obj *obj, void *data);
 
/*!
 * \brief Determine if the connection has died.
 *
 * \param connection The connection to check
 * \retval 1 Yep, it's dead
 * \retval 0 It's alive and well
 */
static int connection_dead(struct odbc_obj *connection)
{
    SQLINTEGER dead;
    SQLRETURN res;
    SQLHSTMT stmt;
 
    if (!connection) {
        return 1;
    }
 
    res = SQLGetConnectAttr(connection->con, SQL_ATTR_CONNECTION_DEAD, &dead, 0, 0);
    if (SQL_SUCCEEDED(res)) {
        return dead == SQL_CD_TRUE ? 1 : 0;
    }
 
    /* If the Driver doesn't support SQL_ATTR_CONNECTION_DEAD do a direct
     * execute of a probing statement and see if that succeeds instead
     */
    stmt = ast_odbc_direct_execute(connection, silent_execute, "SELECT 1");
    if (!stmt) {
        return 1;
    }
 
    SQLFreeHandle(SQL_HANDLE_STMT, stmt);
    return 0;
}
 
/*!
 * \brief Retrieve a DSN, or create it if it does not exist.
 *
 * The created DSN is returned locked. This should be inconsequential
 * to callers in most cases.
 *
 * When finished with the returned structure, the caller must call
 * \ref release_obj_or_dsn
 *
 * \param name Name of the DSN as found in res_odbc.conf
 * \retval NULL Unable to retrieve or create the DSN
 * \retval non-NULL The retrieved/created locked DSN
 */
static struct dsn *get_dsn(const char *name)
{
    struct dsn *dsn;
 
    if (!dsns) {
        return NULL;
    }
 
    ao2_lock(dsns);
    dsn = ao2_find(dsns, name, OBJ_SEARCH_KEY | OBJ_NOLOCK);
    if (!dsn) {
        dsn = create_dsn(name);
    }
    ao2_unlock(dsns);
 
    if (!dsn) {
        return NULL;
    }
 
    ao2_lock(dsn);
    if (!dsn->connection) {
        dsn->connection = ast_odbc_request_obj(name, 0);
        if (!dsn->connection) {
            ao2_unlock(dsn);
            ao2_ref(dsn, -1);
            return NULL;
        }
        return dsn;
    }
 
    if (connection_dead(dsn->connection)) {
        ast_odbc_release_obj(dsn->connection);
        dsn->connection = ast_odbc_request_obj(name, 0);
        if (!dsn->connection) {
            ao2_unlock(dsn);
            ao2_ref(dsn, -1);
            return NULL;
        }
    }
 
    return dsn;
}
 
/*!
 * \brief Get a DB handle via a DSN or directly
 *
 * If single db connection then get the DB handle via DSN
 * else by requesting a connection directly
 *
 * \param dsn_name Name of the DSN as found in res_odbc.conf
 * \param dsn The pointer to the DSN
 * \retval NULL Unable to retrieve the DB handle
 * \retval non-NULL The retrieved DB handle
 */
static struct odbc_obj *get_odbc_obj(const char *dsn_name, struct dsn **dsn)
{
    struct odbc_obj *obj = NULL;
 
    ast_rwlock_rdlock(&single_db_connection_lock);
    if (single_db_connection) {
        if (dsn) {
            *dsn = get_dsn(dsn_name);
            if (*dsn) {
                obj = (*dsn)->connection;
            }
        }
    } else {
        obj = ast_odbc_request_obj(dsn_name, 0);
    }
    ast_rwlock_unlock(&single_db_connection_lock);
 
    return obj;
}
 
/*!
 * \brief Release an ODBC obj or a DSN
 *
 * If single db connection then unlock and unreference the DSN
 * else release the ODBC obj
 *
 * \param obj The pointer to the ODBC obj to release
 * \param dsn The pointer to the dsn to unlock and unreference
 */
static inline void release_obj_or_dsn(struct odbc_obj **obj, struct dsn **dsn)
{
    if (dsn && *dsn) {
        /* If multiple connections are not enabled then the guarantee
         * of a single connection already exists and holding on to the
         * connection would prevent any other user from acquiring it
         * indefinitely.
         */
        if (ast_odbc_get_max_connections((*dsn)->name) < 2) {
            ast_odbc_release_obj((*dsn)->connection);
            (*dsn)->connection = NULL;
        }
        ao2_unlock(*dsn);
        ao2_ref(*dsn, -1);
        *dsn = NULL;
        /* Some callers may provide both an obj and dsn. To ensure that
         * the connection is not released twice we set it to NULL here if
         * present.
         */
        if (obj) {
            *obj = NULL;
        }
    } else if (obj && *obj) {
        ast_odbc_release_obj(*obj);
        *obj = NULL;
    }
}
 
static AST_RWLIST_HEAD_STATIC(queries, acf_odbc_query);
 
static int resultcount = 0;
 
AST_THREADSTORAGE(sql_buf);
AST_THREADSTORAGE(sql2_buf);
AST_THREADSTORAGE(coldata_buf);
AST_THREADSTORAGE(colnames_buf);
 
static int acf_fetch(struct ast_channel *chan, const char *cmd, char *data, char *buf, size_t len);
 
static void odbc_datastore_free(void *data)
{
    struct odbc_datastore *result = data;
    struct odbc_datastore_row *row;
 
    if (!result) {
        return;
    }
 
    AST_LIST_LOCK(result);
    while ((row = AST_LIST_REMOVE_HEAD(result, list))) {
        ast_free(row);
    }
    AST_LIST_UNLOCK(result);
    AST_LIST_HEAD_DESTROY(result);
    ast_free(result);
}
 
/*!
 * \brief Common execution function for SQL queries.
 *
 * \param obj DB connection
 * \param data The query to execute
 * \param silent If true, do not print warnings on failure
 * \retval NULL Failed to execute query
 * \retval non-NULL The executed statement
 */
static SQLHSTMT execute(struct odbc_obj *obj, void *data, int silent)
{
    int res;
    char *sql = data;
    SQLHSTMT stmt;
 
    res = SQLAllocHandle (SQL_HANDLE_STMT, obj->con, &stmt);
    if ((res != SQL_SUCCESS) && (res != SQL_SUCCESS_WITH_INFO)) {
        ast_log(LOG_WARNING, "SQL Alloc Handle failed (%d)!\n", res);
        return NULL;
    }
 
    res = ast_odbc_execute_sql(obj, stmt, sql);
    if ((res != SQL_SUCCESS) && (res != SQL_SUCCESS_WITH_INFO) && (res != SQL_NO_DATA)) {
        if (res == SQL_ERROR && !silent) {
            int i;
            SQLINTEGER nativeerror=0, numfields=0;
            SQLSMALLINT diagbytes=0;
            unsigned char state[10], diagnostic[256];
 
            SQLGetDiagField(SQL_HANDLE_STMT, stmt, 1, SQL_DIAG_NUMBER, &numfields, SQL_IS_INTEGER, &diagbytes);
            for (i = 0; i < numfields; i++) {
                SQLGetDiagRec(SQL_HANDLE_STMT, stmt, i + 1, state, &nativeerror, diagnostic, sizeof(diagnostic), &diagbytes);
                ast_log(LOG_WARNING, "SQL Execute returned an error %d: %s: %s (%d)\n", res, state, diagnostic, diagbytes);
                if (i > 10) {
                    ast_log(LOG_WARNING, "Oh, that was good.  There are really %d diagnostics?\n", (int)numfields);
                    break;
                }
            }
        }
 
        if (!silent) {
            ast_log(LOG_WARNING, "SQL Exec Direct failed (%d)![%s]\n", res, sql);
        }
        SQLCloseCursor(stmt);
        SQLFreeHandle(SQL_HANDLE_STMT, stmt);
        return NULL;
    }
 
    return stmt;
}
 
static SQLHSTMT generic_execute(struct odbc_obj *obj, void *data)
{
    return execute(obj, data, 0);
}
 
static SQLHSTMT silent_execute(struct odbc_obj *obj, void *data)
{
    return execute(obj, data, 1);
}
 
/*
 * Master control routine
 */
static int acf_odbc_write(struct ast_channel *chan, const char *cmd, char *s, const char *value)
{
    struct odbc_obj *obj = NULL;
    struct acf_odbc_query *query;
    char *t, varname[15];
    int i, dsn_num, bogus_chan = 0;
    int transactional = 0;
    AST_DECLARE_APP_ARGS(values,
        AST_APP_ARG(field)[100];
    );
    AST_DECLARE_APP_ARGS(args,
        AST_APP_ARG(field)[100];
    );
    SQLHSTMT stmt = NULL;
    SQLLEN rows=0;
    struct ast_str *buf = ast_str_thread_get(&sql_buf, 16);
    struct ast_str *insertbuf = ast_str_thread_get(&sql2_buf, 16);
    const char *status = "FAILURE";
    struct dsn *dsn = NULL;
 
    if (!buf || !insertbuf) {
        return -1;
    }
 
    AST_RWLIST_RDLOCK(&queries);
    AST_RWLIST_TRAVERSE(&queries, query, list) {
        if (!strcmp(query->acf->name, cmd)) {
            break;
        }
    }
 
    if (!query) {
        ast_log(LOG_ERROR, "No such function '%s'\n", cmd);
        AST_RWLIST_UNLOCK(&queries);
        if (chan) {
            pbx_builtin_setvar_helper(chan, "ODBCSTATUS", status);
        }
        return -1;
    }
 
    AST_STANDARD_APP_ARGS(args, s);
    if (args.argc < query->minargs) {
        ast_log(LOG_ERROR, "%d arguments supplied to '%s' requiring minimum %d\n",
                args.argc, cmd, query->minargs);
        AST_RWLIST_UNLOCK(&queries);
        return -1;
    }
 
    if (!chan) {
        if (!(chan = ast_dummy_channel_alloc())) {
            AST_RWLIST_UNLOCK(&queries);
            return -1;
        }
        bogus_chan = 1;
    }
 
    if (!bogus_chan) {
        ast_autoservice_start(chan);
    }
 
    ast_str_make_space(&buf, strlen(query->sql_write) * 2 + 300);
    /* We only get here if sql_write is set. sql_insert is optional however. */
    if (query->sql_insert) {
        ast_str_make_space(&insertbuf, strlen(query->sql_insert) * 2 + 300);
    }
 
    /* Parse our arguments */
    t = value ? ast_strdupa(value) : "";
 
    if (!s || !t) {
        ast_log(LOG_ERROR, "Out of memory\n");
        AST_RWLIST_UNLOCK(&queries);
        if (!bogus_chan) {
            ast_autoservice_stop(chan);
            pbx_builtin_setvar_helper(chan, "ODBCSTATUS", status);
        } else {
            ast_channel_unref(chan);
        }
        return -1;
    }
 
    snprintf(varname, sizeof(varname), "%u", args.argc);
    pbx_builtin_pushvar_helper(chan, "ARGC", varname);
    for (i = 0; i < args.argc; i++) {
        snprintf(varname, sizeof(varname), "ARG%d", i + 1);
        pbx_builtin_pushvar_helper(chan, varname, args.field[i]);
    }
 
    /* Parse values, just like arguments */
    AST_STANDARD_APP_ARGS(values, t);
    for (i = 0; i < values.argc; i++) {
        snprintf(varname, sizeof(varname), "VAL%d", i + 1);
        pbx_builtin_pushvar_helper(chan, varname, values.field[i]);
    }
 
    /* Additionally set the value as a whole (but push an empty string if value is NULL) */
    pbx_builtin_pushvar_helper(chan, "VALUE", value ? value : "");
 
    ast_str_substitute_variables(&buf, 0, chan, query->sql_write);
    if (query->sql_insert) {
        ast_str_substitute_variables(&insertbuf, 0, chan, query->sql_insert);
    }
 
    if (bogus_chan) {
        chan = ast_channel_unref(chan);
    } else {
        /* Restore prior values */
        pbx_builtin_setvar_helper(chan, "ARGC", NULL);
 
        for (i = 0; i < args.argc; i++) {
            snprintf(varname, sizeof(varname), "ARG%d", i + 1);
            pbx_builtin_setvar_helper(chan, varname, NULL);
        }
 
        for (i = 0; i < values.argc; i++) {
            snprintf(varname, sizeof(varname), "VAL%d", i + 1);
            pbx_builtin_setvar_helper(chan, varname, NULL);
        }
        pbx_builtin_setvar_helper(chan, "VALUE", NULL);
    }
 
    /*!\note
     * Okay, this part is confusing.  Transactions belong to a single database
     * handle.  Therefore, when working with transactions, we CANNOT failover
     * to multiple DSNs.  We MUST have a single handle all the way through the
     * transaction, or else we CANNOT enforce atomicity.
     */
    for (dsn_num = 0; dsn_num < 5; dsn_num++) {
        if (!ast_strlen_zero(query->writehandle[dsn_num])) {
            if (transactional) {
                /* This can only happen second time through or greater. */
                ast_log(LOG_WARNING, "Transactions do not work well with multiple DSNs for 'writehandle'\n");
            }
 
            if ((obj = ast_odbc_retrieve_transaction_obj(chan, query->writehandle[dsn_num]))) {
                transactional = 1;
            } else {
                obj = get_odbc_obj(query->writehandle[dsn_num], &dsn);
                transactional = 0;
            }
 
            if (obj && (stmt = ast_odbc_direct_execute(obj, generic_execute, ast_str_buffer(buf)))) {
                break;
            }
            if (!transactional) {
                release_obj_or_dsn (&obj, &dsn);
            }
        }
    }
 
    if (stmt) {
        SQLRowCount(stmt, &rows);
        SQLCloseCursor(stmt);
        SQLFreeHandle(SQL_HANDLE_STMT, stmt);
 
        if (rows != 0) {
            status = "SUCCESS";
 
        } else if (query->sql_insert) {
            if (!transactional) {
                release_obj_or_dsn (&obj, &dsn);
            }
 
            for (transactional = 0, dsn_num = 0; dsn_num < 5; dsn_num++) {
                if (!ast_strlen_zero(query->writehandle[dsn_num])) {
                    if (transactional) {
                        /* This can only happen second time through or greater. */
                        ast_log(LOG_WARNING, "Transactions do not work well with multiple DSNs for 'writehandle'\n");
                    } else {
                        release_obj_or_dsn (&obj, &dsn);
                    }
 
                    if ((obj = ast_odbc_retrieve_transaction_obj(chan, query->writehandle[dsn_num]))) {
                        transactional = 1;
                    } else {
                        obj = get_odbc_obj(query->writehandle[dsn_num], &dsn);
                        transactional = 0;
                    }
                    if (obj) {
                        stmt = ast_odbc_direct_execute(obj, generic_execute, ast_str_buffer(insertbuf));
                    }
                }
                if (stmt) {
                    status = "FAILOVER";
                    SQLRowCount(stmt, &rows);
                    SQLCloseCursor(stmt);
                    SQLFreeHandle(SQL_HANDLE_STMT, stmt);
                    break;
                }
            }
        }
    }
 
    AST_RWLIST_UNLOCK(&queries);
 
    /* Output the affected rows, for all cases.  In the event of failure, we
     * flag this as -1 rows.  Note that this is different from 0 affected rows
     * which would be the case if we succeeded in our query, but the values did
     * not change. */
    if (!bogus_chan) {
        snprintf(varname, sizeof(varname), "%d", (int)rows);
        pbx_builtin_setvar_helper(chan, "ODBCROWS", varname);
        pbx_builtin_setvar_helper(chan, "ODBCSTATUS", status);
    }
 
    if (!transactional) {
        release_obj_or_dsn (&obj, &dsn);
    }
 
    if (!bogus_chan) {
        ast_autoservice_stop(chan);
    }
 
    return 0;
}
 
static int acf_odbc_read(struct ast_channel *chan, const char *cmd, char *s, char *buf, size_t len)
{
    struct odbc_obj *obj = NULL;
    struct acf_odbc_query *query;
    char varname[15], rowcount[12] = "-1";
    struct ast_str *colnames = ast_str_thread_get(&colnames_buf, 16);
    int res, x, y, buflen = 0, escapecommas, rowlimit = 1, multirow = 0, dsn_num, bogus_chan = 0;
    AST_DECLARE_APP_ARGS(args,
        AST_APP_ARG(field)[100];
    );
    SQLHSTMT stmt = NULL;
    SQLSMALLINT colcount=0;
    SQLLEN indicator;
    SQLSMALLINT collength;
    struct odbc_datastore *resultset = NULL;
    struct odbc_datastore_row *row = NULL;
    struct ast_str *sql = ast_str_thread_get(&sql_buf, 16);
    const char *status = "FAILURE";
    struct dsn *dsn = NULL;
 
    if (!sql || !colnames) {
        if (chan) {
            pbx_builtin_setvar_helper(chan, "ODBCSTATUS", status);
        }
        return -1;
    }
 
    ast_str_reset(colnames);
 
    AST_RWLIST_RDLOCK(&queries);
    AST_RWLIST_TRAVERSE(&queries, query, list) {
        if (!strcmp(query->acf->name, cmd)) {
            break;
        }
    }
 
    if (!query) {
        ast_log(LOG_ERROR, "No such function '%s'\n", cmd);
        AST_RWLIST_UNLOCK(&queries);
        if (chan) {
            pbx_builtin_setvar_helper(chan, "ODBCROWS", rowcount);
            pbx_builtin_setvar_helper(chan, "ODBCSTATUS", status);
        }
        return -1;
    }
 
    AST_STANDARD_APP_ARGS(args, s);
    if (args.argc < query->minargs) {
        ast_log(LOG_ERROR, "%d arguments supplied to '%s' requiring minimum %d\n",
                args.argc, cmd, query->minargs);
        AST_RWLIST_UNLOCK(&queries);
        return -1;
    }
 
    if (!chan) {
        if (!(chan = ast_dummy_channel_alloc())) {
            AST_RWLIST_UNLOCK(&queries);
            return -1;
        }
        bogus_chan = 1;
    }
 
    if (!bogus_chan) {
        ast_autoservice_start(chan);
    }
 
    snprintf(varname, sizeof(varname), "%u", args.argc);
    pbx_builtin_pushvar_helper(chan, "ARGC", varname);
    for (x = 0; x < args.argc; x++) {
        snprintf(varname, sizeof(varname), "ARG%d", x + 1);
        pbx_builtin_pushvar_helper(chan, varname, args.field[x]);
    }
 
    ast_str_substitute_variables(&sql, 0, chan, query->sql_read);
 
    if (bogus_chan) {
        chan = ast_channel_unref(chan);
    } else {
        /* Restore prior values */
        pbx_builtin_setvar_helper(chan, "ARGC", NULL);
 
        for (x = 0; x < args.argc; x++) {
            snprintf(varname, sizeof(varname), "ARG%d", x + 1);
            pbx_builtin_setvar_helper(chan, varname, NULL);
        }
    }
 
    /* Save these flags, so we can release the lock */
    escapecommas = ast_test_flag(query, OPT_ESCAPECOMMAS);
    if (!bogus_chan && ast_test_flag(query, OPT_MULTIROW)) {
        if (!(resultset = ast_calloc(1, sizeof(*resultset)))) {
            pbx_builtin_setvar_helper(chan, "ODBCROWS", rowcount);
            pbx_builtin_setvar_helper(chan, "ODBCSTATUS", status);
            AST_RWLIST_UNLOCK(&queries);
            ast_autoservice_stop(chan);
            return -1;
        }
        AST_LIST_HEAD_INIT(resultset);
        if (query->rowlimit) {
            rowlimit = query->rowlimit;
        } else {
            rowlimit = INT_MAX;
        }
        multirow = 1;
    } else if (!bogus_chan) {
        if (query->rowlimit > 1) {
            rowlimit = query->rowlimit;
            if (!(resultset = ast_calloc(1, sizeof(*resultset)))) {
                pbx_builtin_setvar_helper(chan, "ODBCROWS", rowcount);
                pbx_builtin_setvar_helper(chan, "ODBCSTATUS", status);
                AST_RWLIST_UNLOCK(&queries);
                ast_autoservice_stop(chan);
                return -1;
            }
            AST_LIST_HEAD_INIT(resultset);
        }
    }
    AST_RWLIST_UNLOCK(&queries);
 
    for (dsn_num = 0; dsn_num < 5; dsn_num++) {
        if (!ast_strlen_zero(query->readhandle[dsn_num])) {
            obj = get_odbc_obj(query->readhandle[dsn_num], &dsn);
            if (!obj) {
                continue;
            }
            stmt = ast_odbc_direct_execute(obj, generic_execute, ast_str_buffer(sql));
        }
        if (stmt) {
            break;
        }
        release_obj_or_dsn (&obj, &dsn);
    }
 
    if (!stmt) {
        ast_log(LOG_ERROR, "Unable to execute query [%s]\n", ast_str_buffer(sql));
        release_obj_or_dsn (&obj, &dsn);
        if (!bogus_chan) {
            pbx_builtin_setvar_helper(chan, "ODBCROWS", rowcount);
            ast_autoservice_stop(chan);
        }
        odbc_datastore_free(resultset);
        return -1;
    }
 
    res = SQLNumResultCols(stmt, &colcount);
    if ((res != SQL_SUCCESS) && (res != SQL_SUCCESS_WITH_INFO)) {
        ast_log(LOG_WARNING, "SQL Column Count error!\n[%s]\n\n", ast_str_buffer(sql));
        SQLCloseCursor(stmt);
        SQLFreeHandle (SQL_HANDLE_STMT, stmt);
        release_obj_or_dsn (&obj, &dsn);
        if (!bogus_chan) {
            pbx_builtin_setvar_helper(chan, "ODBCROWS", rowcount);
            ast_autoservice_stop(chan);
        }
        odbc_datastore_free(resultset);
        return -1;
    }
 
    if (colcount <= 0) {
        ast_verb(4, "Returned %d columns [%s]\n", colcount, ast_str_buffer(sql));
        buf[0] = '\0';
        SQLCloseCursor(stmt);
        SQLFreeHandle (SQL_HANDLE_STMT, stmt);
        release_obj_or_dsn (&obj, &dsn);
        if (!bogus_chan) {
            pbx_builtin_setvar_helper(chan, "ODBCROWS", "0");
            pbx_builtin_setvar_helper(chan, "ODBCSTATUS", "NODATA");
            ast_autoservice_stop(chan);
        }
        odbc_datastore_free(resultset);
        return 0;
    }
 
    res = SQLFetch(stmt);
    if ((res != SQL_SUCCESS) && (res != SQL_SUCCESS_WITH_INFO)) {
        int res1 = -1;
        if (res == SQL_NO_DATA) {
            ast_verb(4, "Found no rows [%s]\n", ast_str_buffer(sql));
            res1 = 0;
            buf[0] = '\0';
            ast_copy_string(rowcount, "0", sizeof(rowcount));
            status = "NODATA";
        } else {
            ast_log(LOG_WARNING, "Error %d in FETCH [%s]\n", res, ast_str_buffer(sql));
            status = "FETCHERROR";
        }
        SQLCloseCursor(stmt);
        SQLFreeHandle(SQL_HANDLE_STMT, stmt);
        release_obj_or_dsn (&obj, &dsn);
        if (!bogus_chan) {
            pbx_builtin_setvar_helper(chan, "ODBCROWS", rowcount);
            pbx_builtin_setvar_helper(chan, "ODBCSTATUS", status);
            ast_autoservice_stop(chan);
        }
        odbc_datastore_free(resultset);
        return res1;
    }
 
    status = "SUCCESS";
 
    for (y = 0; y < rowlimit; y++) {
        buf[0] = '\0';
        for (x = 0; x < colcount; x++) {
            int i;
            struct ast_str *coldata = ast_str_thread_get(&coldata_buf, 16);
            char *ptrcoldata;
 
            if (!coldata) {
                odbc_datastore_free(resultset);
                SQLCloseCursor(stmt);
                SQLFreeHandle(SQL_HANDLE_STMT, stmt);
                release_obj_or_dsn (&obj, &dsn);
                if (!bogus_chan) {
                    pbx_builtin_setvar_helper(chan, "ODBCSTATUS", "MEMERROR");
                    ast_autoservice_stop(chan);
                }
                return -1;
            }
 
            if (y == 0) {
                char colname[256];
                SQLLEN octetlength = 0;
 
                res = SQLDescribeCol(stmt, x + 1, (unsigned char *)colname, sizeof(colname), &collength, NULL, NULL, NULL, NULL);
                ast_debug(3, "Got collength of %d for column '%s' (offset %d)\n", (int)collength, colname, x);
                if (((res != SQL_SUCCESS) && (res != SQL_SUCCESS_WITH_INFO)) || collength == 0) {
                    snprintf(colname, sizeof(colname), "field%d", x);
                }
 
                SQLColAttribute(stmt, x + 1, SQL_DESC_OCTET_LENGTH, NULL, 0, NULL, &octetlength);
 
                ast_str_make_space(&coldata, octetlength + 1);
 
                if (ast_str_strlen(colnames)) {
                    ast_str_append(&colnames, 0, ",");
                }
                ast_str_append_escapecommas(&colnames, 0, colname, sizeof(colname));
 
                if (resultset) {
                    void *tmp = ast_realloc(resultset, sizeof(*resultset) + ast_str_strlen(colnames) + 1);
                    if (!tmp) {
                        ast_log(LOG_ERROR, "No space for a new resultset?\n");
                        odbc_datastore_free(resultset);
                        SQLCloseCursor(stmt);
                        SQLFreeHandle(SQL_HANDLE_STMT, stmt);
                        release_obj_or_dsn (&obj, &dsn);
                        if (!bogus_chan) {
                            pbx_builtin_setvar_helper(chan, "ODBCROWS", rowcount);
                            pbx_builtin_setvar_helper(chan, "ODBCSTATUS", "MEMERROR");
                            ast_autoservice_stop(chan);
                        }
                        return -1;
                    }
                    resultset = tmp;
                    strcpy((char *)resultset + sizeof(*resultset), ast_str_buffer(colnames));
                }
            }
 
            buflen = strlen(buf);
            res = ast_odbc_ast_str_SQLGetData(&coldata, -1, stmt, x + 1, SQL_CHAR, &indicator);
            if (indicator == SQL_NULL_DATA) {
                ast_debug(3, "Got NULL data\n");
                ast_str_reset(coldata);
                res = SQL_SUCCESS;
            }
 
            if ((res != SQL_SUCCESS) && (res != SQL_SUCCESS_WITH_INFO)) {
                ast_log(LOG_WARNING, "SQL Get Data error!\n[%s]\n\n", ast_str_buffer(sql));
                y = -1;
                buf[0] = '\0';
                goto end_acf_read;
            }
 
            ast_debug(2, "Got coldata of '%s'\n", ast_str_buffer(coldata));
 
            if (x) {
                buf[buflen++] = ',';
            }
 
            /* Copy data, encoding '\' and ',' for the argument parser */
            ptrcoldata = ast_str_buffer(coldata);
            for (i = 0; i < ast_str_strlen(coldata); i++) {
                if (escapecommas && (ptrcoldata[i] == '\\' || ptrcoldata[i] == ',')) {
                    buf[buflen++] = '\\';
                }
                buf[buflen++] = ptrcoldata[i];
 
                if (buflen >= len - 2) {
                    break;
                }
 
                if (ptrcoldata[i] == '\0') {
                    break;
                }
            }
 
            buf[buflen] = '\0';
            ast_debug(2, "buf is now set to '%s'\n", buf);
        }
        ast_debug(2, "buf is now set to '%s'\n", buf);
 
        if (resultset) {
            row = ast_calloc(1, sizeof(*row) + buflen + 1);
            if (!row) {
                ast_log(LOG_ERROR, "Unable to allocate space for more rows in this resultset.\n");
                status = "MEMERROR";
                goto end_acf_read;
            }
            strcpy((char *)row + sizeof(*row), buf);
            AST_LIST_INSERT_TAIL(resultset, row, list);
 
            /* Get next row */
            res = SQLFetch(stmt);
            if ((res != SQL_SUCCESS) && (res != SQL_SUCCESS_WITH_INFO)) {
                if (res != SQL_NO_DATA) {
                    ast_log(LOG_WARNING, "Error %d in FETCH [%s]\n", res, ast_str_buffer(sql));
                }
                /* Number of rows in the resultset */
                y++;
                break;
            }
        }
    }
 
end_acf_read:
    if (!bogus_chan) {
        snprintf(rowcount, sizeof(rowcount), "%d", y);
        pbx_builtin_setvar_helper(chan, "ODBCROWS", rowcount);
        pbx_builtin_setvar_helper(chan, "ODBCSTATUS", status);
        pbx_builtin_setvar_helper(chan, "~ODBCFIELDS~", ast_str_buffer(colnames));
        if (resultset) {
            struct ast_datastore *odbc_store;
            if (multirow) {
                int uid;
                uid = ast_atomic_fetchadd_int(&resultcount, +1) + 1;
                snprintf(buf, len, "%d", uid);
            } else {
                /* Name of the query is name of the resultset */
                ast_copy_string(buf, cmd, len);
 
                /* If there's one with the same name already, free it */
                ast_channel_lock(chan);
                if ((odbc_store = ast_channel_datastore_find(chan, &odbc_info, buf))) {
                    ast_channel_datastore_remove(chan, odbc_store);
                    ast_datastore_free(odbc_store);
                }
                ast_channel_unlock(chan);
            }
            odbc_store = ast_datastore_alloc(&odbc_info, buf);
            if (!odbc_store) {
                ast_log(LOG_ERROR, "Rows retrieved, but unable to store it in the channel.  Results fail.\n");
                odbc_datastore_free(resultset);
                SQLCloseCursor(stmt);
                SQLFreeHandle(SQL_HANDLE_STMT, stmt);
                release_obj_or_dsn (&obj, &dsn);
                pbx_builtin_setvar_helper(chan, "ODBCSTATUS", "MEMERROR");
                ast_autoservice_stop(chan);
                return -1;
            }
            odbc_store->data = resultset;
            ast_channel_lock(chan);
            ast_channel_datastore_add(chan, odbc_store);
            ast_channel_unlock(chan);
        }
    }
    SQLCloseCursor(stmt);
    SQLFreeHandle(SQL_HANDLE_STMT, stmt);
    release_obj_or_dsn (&obj, &dsn);
    if (resultset && !multirow) {
        /* Fetch the first resultset */
        if (!acf_fetch(chan, "", buf, buf, len)) {
            buf[0] = '\0';
        }
    }
    if (!bogus_chan) {
        ast_autoservice_stop(chan);
    }
    return 0;
}
 
static int acf_escape(struct ast_channel *chan, const char *cmd, char *data, char *buf, size_t len, char character)
{
    char *out = buf;
 
    for (; *data && out - buf < len; data++) {
        if (*data == character) {
            *out = character;
            out++;
        }
        *out++ = *data;
    }
    *out = '\0';
 
    return 0;
}
 
static int acf_escape_ticks(struct ast_channel *chan, const char *cmd, char *data, char *buf, size_t len)
{
    return acf_escape(chan, cmd, data, buf, len, '\'');
}
 
static struct ast_custom_function escape_function = {
    .name = "SQL_ESC",
    .read = acf_escape_ticks,
    .write = NULL,
};
 
static int acf_escape_backslashes(struct ast_channel *chan, const char *cmd, char *data, char *buf, size_t len)
{
    return acf_escape(chan, cmd, data, buf, len, '\\');
}
 
static struct ast_custom_function escape_backslashes_function = {
    .name = "SQL_ESC_BACKSLASHES",
    .read = acf_escape_backslashes,
    .write = NULL,
};
 
static int acf_fetch(struct ast_channel *chan, const char *cmd, char *data, char *buf, size_t len)
{
    struct ast_datastore *store;
    struct odbc_datastore *resultset;
    struct odbc_datastore_row *row;
 
    if (!chan) {
        ast_log(LOG_WARNING, "No channel was provided to %s function.\n", cmd);
        return -1;
    }
 
    ast_channel_lock(chan);
    store = ast_channel_datastore_find(chan, &odbc_info, data);
    if (!store) {
        ast_channel_unlock(chan);
        pbx_builtin_setvar_helper(chan, "ODBC_FETCH_STATUS", "FAILURE");
        return -1;
    }
    resultset = store->data;
    AST_LIST_LOCK(resultset);
    row = AST_LIST_REMOVE_HEAD(resultset, list);
    AST_LIST_UNLOCK(resultset);
    if (!row) {
        /* Cleanup datastore */
        ast_channel_datastore_remove(chan, store);
        ast_datastore_free(store);
        ast_channel_unlock(chan);
        pbx_builtin_setvar_helper(chan, "ODBC_FETCH_STATUS", "FAILURE");
        return -1;
    }
    pbx_builtin_setvar_helper(chan, "~ODBCFIELDS~", resultset->names);
    ast_channel_unlock(chan);
    ast_copy_string(buf, row->data, len);
    ast_free(row);
    pbx_builtin_setvar_helper(chan, "ODBC_FETCH_STATUS", "SUCCESS");
    return 0;
}
 
static struct ast_custom_function fetch_function = {
    .name = "ODBC_FETCH",
    .read = acf_fetch,
    .write = NULL,
};
 
static char *app_odbcfinish = "ODBCFinish";
 
static int exec_odbcfinish(struct ast_channel *chan, const char *data)
{
    struct ast_datastore *store;
 
    ast_channel_lock(chan);
    store = ast_channel_datastore_find(chan, &odbc_info, data);
    if (store) {
        ast_channel_datastore_remove(chan, store);
        ast_datastore_free(store);
    }
    ast_channel_unlock(chan);
    return 0;
}
 
static int free_acf_query(struct acf_odbc_query *query)
{
    if (query) {
        if (query->acf) {
            if (query->acf->name)
                ast_free((char *)query->acf->name);
            ast_string_field_free_memory(query->acf);
            ast_free(query->acf);
        }
        ast_free(query->sql_read);
        ast_free(query->sql_write);
        ast_free(query->sql_insert);
        ast_free(query);
    }
    return 0;
}
 
static int init_acf_query(struct ast_config *cfg, char *catg, struct acf_odbc_query **query)
{
    const char *tmp;
    const char *tmp2 = NULL;
    int i;
 
    if (!cfg || !catg) {
        return EINVAL;
    }
 
    if (!(*query = ast_calloc(1, sizeof(**query)))) {
        return ENOMEM;
    }
 
    if (((tmp = ast_variable_retrieve(cfg, catg, "writehandle"))) || ((tmp = ast_variable_retrieve(cfg, catg, "dsn")))) {
        char *tmp2 = ast_strdupa(tmp);
        AST_DECLARE_APP_ARGS(writeconf,
            AST_APP_ARG(dsn)[5];
        );
        AST_STANDARD_APP_ARGS(writeconf, tmp2);
        for (i = 0; i < 5; i++) {
            if (!ast_strlen_zero(writeconf.dsn[i]))
                ast_copy_string((*query)->writehandle[i], writeconf.dsn[i], sizeof((*query)->writehandle[i]));
        }
    }
 
    if ((tmp = ast_variable_retrieve(cfg, catg, "readhandle"))) {
        char *tmp2 = ast_strdupa(tmp);
        AST_DECLARE_APP_ARGS(readconf,
            AST_APP_ARG(dsn)[5];
        );
        AST_STANDARD_APP_ARGS(readconf, tmp2);
        for (i = 0; i < 5; i++) {
            if (!ast_strlen_zero(readconf.dsn[i]))
                ast_copy_string((*query)->readhandle[i], readconf.dsn[i], sizeof((*query)->readhandle[i]));
        }
    } else {
        /* If no separate readhandle, then use the writehandle for reading */
        for (i = 0; i < 5; i++) {
            if (!ast_strlen_zero((*query)->writehandle[i]))
                ast_copy_string((*query)->readhandle[i], (*query)->writehandle[i], sizeof((*query)->readhandle[i]));
        }
    }
 
    if ((tmp = ast_variable_retrieve(cfg, catg, "readsql")) ||
            (tmp2 = ast_variable_retrieve(cfg, catg, "read"))) {
        if (!tmp) {
            ast_log(LOG_WARNING, "Parameter 'read' is deprecated for category %s.  Please use 'readsql' instead.\n", catg);
            tmp = tmp2;
        }
        if (*tmp != '\0') { /* non-empty string */
            if (!((*query)->sql_read = ast_strdup(tmp))) {
                free_acf_query(*query);
                *query = NULL;
                return ENOMEM;
            }
        }
    }
 
    if ((*query)->sql_read && ast_strlen_zero((*query)->readhandle[0])) {
        free_acf_query(*query);
        *query = NULL;
        ast_log(LOG_ERROR, "There is SQL, but no ODBC class to be used for reading: %s\n", catg);
        return EINVAL;
    }
 
    if ((tmp = ast_variable_retrieve(cfg, catg, "writesql")) ||
            (tmp2 = ast_variable_retrieve(cfg, catg, "write"))) {
        if (!tmp) {
            ast_log(LOG_WARNING, "Parameter 'write' is deprecated for category %s.  Please use 'writesql' instead.\n", catg);
            tmp = tmp2;
        }
        if (*tmp != '\0') { /* non-empty string */
            if (!((*query)->sql_write = ast_strdup(tmp))) {
                free_acf_query(*query);
                *query = NULL;
                return ENOMEM;
            }
        }
    }
 
    if ((*query)->sql_write && ast_strlen_zero((*query)->writehandle[0])) {
        free_acf_query(*query);
        *query = NULL;
        ast_log(LOG_ERROR, "There is SQL, but no ODBC class to be used for writing: %s\n", catg);
        return EINVAL;
    }
 
    if ((tmp = ast_variable_retrieve(cfg, catg, "insertsql"))) {
        if (*tmp != '\0') { /* non-empty string */
            if (!((*query)->sql_insert = ast_strdup(tmp))) {
                free_acf_query(*query);
                *query = NULL;
                return ENOMEM;
            }
        }
    }
 
    /* Allow escaping of embedded commas in fields to be turned off */
    ast_set_flag((*query), OPT_ESCAPECOMMAS);
    if ((tmp = ast_variable_retrieve(cfg, catg, "escapecommas"))) {
        if (ast_false(tmp))
            ast_clear_flag((*query), OPT_ESCAPECOMMAS);
    }
 
    if ((tmp = ast_variable_retrieve(cfg, catg, "mode"))) {
        if (strcasecmp(tmp, "multirow") == 0)
            ast_set_flag((*query), OPT_MULTIROW);
        if ((tmp = ast_variable_retrieve(cfg, catg, "rowlimit")))
            sscanf(tmp, "%30d", &((*query)->rowlimit));
    }
 
    if ((tmp = ast_variable_retrieve(cfg, catg, "minargs"))) {
        sscanf(tmp, "%30d", &((*query)->minargs));
    }
 
    (*query)->acf = ast_calloc(1, sizeof(struct ast_custom_function));
    if (!(*query)->acf) {
        free_acf_query(*query);
        *query = NULL;
        return ENOMEM;
    }
    if (ast_string_field_init((*query)->acf, 128)) {
        free_acf_query(*query);
        *query = NULL;
        return ENOMEM;
    }
 
    if ((tmp = ast_variable_retrieve(cfg, catg, "prefix")) && !ast_strlen_zero(tmp)) {
        if (ast_asprintf((char **)&((*query)->acf->name), "%s_%s", tmp, catg) < 0) {
            (*query)->acf->name = NULL;
        }
    } else {
        if (ast_asprintf((char **)&((*query)->acf->name), "ODBC_%s", catg) < 0) {
            (*query)->acf->name = NULL;
        }
    }
 
    if (!(*query)->acf->name) {
        free_acf_query(*query);
        *query = NULL;
        return ENOMEM;
    }
 
    if ((tmp = ast_variable_retrieve(cfg, catg, "syntax")) && !ast_strlen_zero(tmp)) {
        ast_string_field_build((*query)->acf, syntax, "%s(%s)", (*query)->acf->name, tmp);
    } else {
        ast_string_field_build((*query)->acf, syntax, "%s(<arg1>[...[,<argN>]])", (*query)->acf->name);
    }
 
    if (ast_strlen_zero((*query)->acf->syntax)) {
        free_acf_query(*query);
        *query = NULL;
        return ENOMEM;
    }
 
    if ((tmp = ast_variable_retrieve(cfg, catg, "synopsis")) && !ast_strlen_zero(tmp)) {
        ast_string_field_set((*query)->acf, synopsis, tmp);
    } else {
        ast_string_field_set((*query)->acf, synopsis, "Runs the referenced query with the specified arguments");
    }
 
    if (ast_strlen_zero((*query)->acf->synopsis)) {
        free_acf_query(*query);
        *query = NULL;
        return ENOMEM;
    }
 
    if ((*query)->sql_read && (*query)->sql_write) {
        ast_string_field_build((*query)->acf, desc,
                    "Runs the following query, as defined in func_odbc.conf, performing\n"
                    "substitution of the arguments into the query as specified by ${ARG1},\n"
                    "${ARG2}, ... ${ARGn}.  When setting the function, the values are provided\n"
                    "either in whole as ${VALUE} or parsed as ${VAL1}, ${VAL2}, ... ${VALn}.\n"
                    "%s"
                    "\nRead:\n%s\n\nWrite:\n%s%s%s",
                    (*query)->sql_insert ?
                        "If the write query affects no rows, the insert query will be\n"
                        "performed.\n" : "",
                    (*query)->sql_read,
                    (*query)->sql_write,
                    (*query)->sql_insert ? "\n\nInsert:\n" : "",
                    (*query)->sql_insert ? (*query)->sql_insert : "");
    } else if ((*query)->sql_read) {
        ast_string_field_build((*query)->acf, desc,
                    "Runs the following query, as defined in func_odbc.conf, performing\n"
                    "substitution of the arguments into the query as specified by ${ARG1},\n"
                    "${ARG2}, ... ${ARGn}.  This function may only be read, not set.\n\nSQL:\n%s",
                    (*query)->sql_read);
    } else if ((*query)->sql_write) {
        ast_string_field_build((*query)->acf, desc,
                    "Runs the following query, as defined in func_odbc.conf, performing\n"
                    "substitution of the arguments into the query as specified by ${ARG1},\n"
                    "${ARG2}, ... ${ARGn}.  The values are provided either in whole as\n"
                    "${VALUE} or parsed as ${VAL1}, ${VAL2}, ... ${VALn}.\n"
                    "This function may only be set.\n%s\nSQL:\n%s%s%s",
                    (*query)->sql_insert ?
                        "If the write query affects no rows, the insert query will be\n"
                        "performed.\n" : "",
                    (*query)->sql_write,
                    (*query)->sql_insert ? "\n\nInsert:\n" : "",
                    (*query)->sql_insert ? (*query)->sql_insert : "");
    } else {
        free_acf_query(*query);
        *query = NULL;
        ast_log(LOG_WARNING, "Section '%s' was found, but there was no SQL to execute.  Ignoring.\n", catg);
        return EINVAL;
    }
 
    if (ast_strlen_zero((*query)->acf->desc)) {
        free_acf_query(*query);
        *query = NULL;
        return ENOMEM;
    }
 
    if ((*query)->sql_read) {
        (*query)->acf->read = acf_odbc_read;
    }
 
    if ((*query)->sql_write) {
        (*query)->acf->write = acf_odbc_write;
    }
 
    return 0;
}
 
static char *cli_odbc_read(struct ast_cli_entry *e, int cmd, struct ast_cli_args *a)
{
    AST_DECLARE_APP_ARGS(args,
        AST_APP_ARG(field)[100];
    );
    struct ast_str *sql;
    char *char_args, varname[15];
    struct acf_odbc_query *query;
    struct ast_channel *chan;
    int i;
 
    switch (cmd) {
    case CLI_INIT:
        e->command = "odbc read";
        e->usage =
            "Usage: odbc read <name> <args> [exec]\n"
            "       Evaluates the SQL provided in the ODBC function <name>, and\n"
            "       optionally executes the function.  This function is intended for\n"
            "       testing purposes.  Remember to quote arguments containing spaces.\n";
        return NULL;
    case CLI_GENERATE:
        if (a->pos == 2) {
            int wordlen = strlen(a->word), which = 0;
            /* Complete function name */
            AST_RWLIST_RDLOCK(&queries);
            AST_RWLIST_TRAVERSE(&queries, query, list) {
                if (!strncasecmp(query->acf->name, a->word, wordlen)) {
                    if (++which > a->n) {
                        char *res = ast_strdup(query->acf->name);
                        AST_RWLIST_UNLOCK(&queries);
                        return res;
                    }
                }
            }
            AST_RWLIST_UNLOCK(&queries);
            return NULL;
        } else if (a->pos == 4) {
            static const char * const completions[] = { "exec", NULL };
            return ast_cli_complete(a->word, completions, a->n);
        } else {
            return NULL;
        }
    }
 
    if (a->argc < 4 || a->argc > 5) {
        return CLI_SHOWUSAGE;
    }
 
    sql = ast_str_thread_get(&sql_buf, 16);
    if (!sql) {
        return CLI_FAILURE;
    }
 
    AST_RWLIST_RDLOCK(&queries);
    AST_RWLIST_TRAVERSE(&queries, query, list) {
        if (!strcmp(query->acf->name, a->argv[2])) {
            break;
        }
    }
 
    if (!query) {
        ast_cli(a->fd, "No such query '%s'\n", a->argv[2]);
        AST_RWLIST_UNLOCK(&queries);
        return CLI_SHOWUSAGE;
    }
 
    if (!query->sql_read) {
        ast_cli(a->fd, "The function %s has no readsql parameter.\n", a->argv[2]);
        AST_RWLIST_UNLOCK(&queries);
        return CLI_SUCCESS;
    }
 
    ast_str_make_space(&sql, strlen(query->sql_read) * 2 + 300);
 
    /* Evaluate function */
    char_args = ast_strdupa(a->argv[3]);
 
    chan = ast_dummy_channel_alloc();
    if (!chan) {
        AST_RWLIST_UNLOCK(&queries);
        return CLI_FAILURE;
    }
 
    AST_STANDARD_APP_ARGS(args, char_args);
    for (i = 0; i < args.argc; i++) {
        snprintf(varname, sizeof(varname), "ARG%d", i + 1);
        pbx_builtin_pushvar_helper(chan, varname, args.field[i]);
    }
 
    ast_str_substitute_variables(&sql, 0, chan, query->sql_read);
    chan = ast_channel_unref(chan);
 
    if (a->argc == 5 && !strcmp(a->argv[4], "exec")) {
        /* Execute the query */
        struct odbc_obj *obj = NULL;
        struct dsn *dsn = NULL;
        int dsn_num, executed = 0;
        SQLHSTMT stmt;
        int rows = 0, res, x;
        SQLSMALLINT colcount = 0, collength;
        SQLLEN indicator, octetlength;
        struct ast_str *coldata = ast_str_thread_get(&coldata_buf, 16);
        char colname[256];
 
        if (!coldata) {
            AST_RWLIST_UNLOCK(&queries);
            return CLI_SUCCESS;
        }
 
        for (dsn_num = 0; dsn_num < 5; dsn_num++) {
            if (ast_strlen_zero(query->readhandle[dsn_num])) {
                continue;
            }
            obj = get_odbc_obj(query->readhandle[dsn_num], &dsn);
            if (!obj) {
                continue;
            }
            ast_debug(1, "Found handle %s\n", query->readhandle[dsn_num]);
 
            if (!(stmt = ast_odbc_direct_execute(obj, generic_execute, ast_str_buffer(sql)))) {
                release_obj_or_dsn (&obj, &dsn);
                continue;
            }
 
            executed = 1;
 
            res = SQLNumResultCols(stmt, &colcount);
            if ((res != SQL_SUCCESS) && (res != SQL_SUCCESS_WITH_INFO)) {
                ast_cli(a->fd, "SQL Column Count error!\n[%s]\n\n", ast_str_buffer(sql));
                SQLCloseCursor(stmt);
                SQLFreeHandle (SQL_HANDLE_STMT, stmt);
                release_obj_or_dsn (&obj, &dsn);
                AST_RWLIST_UNLOCK(&queries);
                return CLI_SUCCESS;
            }
 
            if (colcount <= 0) {
                SQLCloseCursor(stmt);
                SQLFreeHandle (SQL_HANDLE_STMT, stmt);
                release_obj_or_dsn (&obj, &dsn);
                ast_cli(a->fd, "Returned %d columns.  Query executed on handle %d:%s [%s]\n", colcount, dsn_num, query->readhandle[dsn_num], ast_str_buffer(sql));
                AST_RWLIST_UNLOCK(&queries);
                return CLI_SUCCESS;
            }
 
            res = SQLFetch(stmt);
            if ((res != SQL_SUCCESS) && (res != SQL_SUCCESS_WITH_INFO)) {
                SQLCloseCursor(stmt);
                SQLFreeHandle(SQL_HANDLE_STMT, stmt);
                release_obj_or_dsn (&obj, &dsn);
                if (res == SQL_NO_DATA) {
                    ast_cli(a->fd, "Returned %d rows.  Query executed on handle %d:%s [%s]\n", rows, dsn_num, query->readhandle[dsn_num], ast_str_buffer(sql));
                    break;
                } else {
                    ast_cli(a->fd, "Error %d in FETCH [%s]\n", res, ast_str_buffer(sql));
                }
                AST_RWLIST_UNLOCK(&queries);
                return CLI_SUCCESS;
            }
            for (;;) {
                for (x = 0; x < colcount; x++) {
                    res = SQLDescribeCol(stmt, x + 1, (unsigned char *)colname, sizeof(colname), &collength, NULL, NULL, NULL, NULL);
                    if (((res != SQL_SUCCESS) && (res != SQL_SUCCESS_WITH_INFO)) || collength == 0) {
                        snprintf(colname, sizeof(colname), "field%d", x);
                    }
 
                    octetlength = 0;
                    SQLColAttribute(stmt, x + 1, SQL_DESC_OCTET_LENGTH, NULL, 0, NULL, &octetlength);
 
                    res = ast_odbc_ast_str_SQLGetData(&coldata, octetlength + 1, stmt, x + 1, SQL_CHAR, &indicator);
                    if (indicator == SQL_NULL_DATA) {
                        ast_str_set(&coldata, 0, "(nil)");
                        res = SQL_SUCCESS;
                    }
 
                    if ((res != SQL_SUCCESS) && (res != SQL_SUCCESS_WITH_INFO)) {
                        ast_cli(a->fd, "SQL Get Data error %d!\n[%s]\n\n", res, ast_str_buffer(sql));
                        SQLCloseCursor(stmt);
                        SQLFreeHandle(SQL_HANDLE_STMT, stmt);
                        release_obj_or_dsn (&obj, &dsn);
                        AST_RWLIST_UNLOCK(&queries);
                        return CLI_SUCCESS;
                    }
 
                    ast_cli(a->fd, "%-20.20s  %s\n", colname, ast_str_buffer(coldata));
                }
                rows++;
 
                /* Get next row */
                res = SQLFetch(stmt);
                if ((res != SQL_SUCCESS) && (res != SQL_SUCCESS_WITH_INFO)) {
                    break;
                }
                ast_cli(a->fd, "%-20.20s  %s\n", "----------", "----------");
            }
            SQLCloseCursor(stmt);
            SQLFreeHandle(SQL_HANDLE_STMT, stmt);
            release_obj_or_dsn (&obj, &dsn);
            ast_cli(a->fd, "Returned %d row%s.  Query executed on handle %d [%s]\n", rows, rows == 1 ? "" : "s", dsn_num, query->readhandle[dsn_num]);
            break;
        }
        release_obj_or_dsn (&obj, &dsn);
 
        if (!executed) {
            ast_cli(a->fd, "Failed to execute query. [%s]\n", ast_str_buffer(sql));
        }
    } else { /* No execution, just print out the resulting SQL */
        ast_cli(a->fd, "%s\n", ast_str_buffer(sql));
    }
    AST_RWLIST_UNLOCK(&queries);
    return CLI_SUCCESS;
}
 
static char *cli_odbc_write(struct ast_cli_entry *e, int cmd, struct ast_cli_args *a)
{
    AST_DECLARE_APP_ARGS(values,
        AST_APP_ARG(field)[100];
    );
    AST_DECLARE_APP_ARGS(args,
        AST_APP_ARG(field)[100];
    );
    struct ast_str *sql;
    char *char_args, *char_values, varname[15];
    struct acf_odbc_query *query;
    struct ast_channel *chan;
    int i;
 
    switch (cmd) {
    case CLI_INIT:
        e->command = "odbc write";
        e->usage =
            "Usage: odbc write <name> <args> <value> [exec]\n"
            "       Evaluates the SQL provided in the ODBC function <name>, and\n"
            "       optionally executes the function.  This function is intended for\n"
            "       testing purposes.  Remember to quote arguments containing spaces.\n";
        return NULL;
    case CLI_GENERATE:
        if (a->pos == 2) {
            int wordlen = strlen(a->word), which = 0;
            /* Complete function name */
            AST_RWLIST_RDLOCK(&queries);
            AST_RWLIST_TRAVERSE(&queries, query, list) {
                if (!strncasecmp(query->acf->name, a->word, wordlen)) {
                    if (++which > a->n) {
                        char *res = ast_strdup(query->acf->name);
                        AST_RWLIST_UNLOCK(&queries);
                        return res;
                    }
                }
            }
            AST_RWLIST_UNLOCK(&queries);
            return NULL;
        } else if (a->pos == 5) {
            static const char * const completions[] = { "exec", NULL };
            return ast_cli_complete(a->word, completions, a->n);
        } else {
            return NULL;
        }
    }
 
    if (a->argc < 5 || a->argc > 6) {
        return CLI_SHOWUSAGE;
    }
 
    sql = ast_str_thread_get(&sql_buf, 16);
    if (!sql) {
        return CLI_FAILURE;
    }
 
    AST_RWLIST_RDLOCK(&queries);
    AST_RWLIST_TRAVERSE(&queries, query, list) {
        if (!strcmp(query->acf->name, a->argv[2])) {
            break;
        }
    }
 
    if (!query) {
        ast_cli(a->fd, "No such query '%s'\n", a->argv[2]);
        AST_RWLIST_UNLOCK(&queries);
        return CLI_SHOWUSAGE;
    }
 
    if (!query->sql_write) {
        ast_cli(a->fd, "The function %s has no writesql parameter.\n", a->argv[2]);
        AST_RWLIST_UNLOCK(&queries);
        return CLI_SUCCESS;
    }
 
    /* FIXME: The code below duplicates code found in acf_odbc_write but
     * lacks the newer sql_insert additions. */
 
    ast_str_make_space(&sql, strlen(query->sql_write) * 2 + 300);
 
    /* Evaluate function */
    char_args = ast_strdupa(a->argv[3]);
    char_values = ast_strdupa(a->argv[4]);
 
    chan = ast_dummy_channel_alloc();
    if (!chan) {
        AST_RWLIST_UNLOCK(&queries);
        return CLI_FAILURE;
    }
 
    AST_STANDARD_APP_ARGS(args, char_args);
    for (i = 0; i < args.argc; i++) {
        snprintf(varname, sizeof(varname), "ARG%d", i + 1);
        pbx_builtin_pushvar_helper(chan, varname, args.field[i]);
    }
 
    /* Parse values, just like arguments */
    AST_STANDARD_APP_ARGS(values, char_values);
    for (i = 0; i < values.argc; i++) {
        snprintf(varname, sizeof(varname), "VAL%d", i + 1);
        pbx_builtin_pushvar_helper(chan, varname, values.field[i]);
    }
 
    /* Additionally set the value as a whole (but push an empty string if value is NULL) */
    pbx_builtin_pushvar_helper(chan, "VALUE", S_OR(a->argv[4], ""));
    ast_str_substitute_variables(&sql, 0, chan, query->sql_write);
    ast_debug(1, "SQL is %s\n", ast_str_buffer(sql));
 
    chan = ast_channel_unref(chan);
 
    if (a->argc == 6 && !strcmp(a->argv[5], "exec")) {
        /* Execute the query */
        struct odbc_obj *obj = NULL;
        struct dsn *dsn = NULL;
        int dsn_num, executed = 0;
        SQLHSTMT stmt;
        SQLLEN rows = -1;
 
        for (dsn_num = 0; dsn_num < 5; dsn_num++) {
            if (ast_strlen_zero(query->writehandle[dsn_num])) {
                continue;
            }
            obj = get_odbc_obj(query->writehandle[dsn_num], &dsn);
            if (!obj) {
                continue;
            }
            if (!(stmt = ast_odbc_direct_execute(obj, generic_execute, ast_str_buffer(sql)))) {
                release_obj_or_dsn (&obj, &dsn);
                continue;
            }
 
            SQLRowCount(stmt, &rows);
            SQLCloseCursor(stmt);
            SQLFreeHandle(SQL_HANDLE_STMT, stmt);
            release_obj_or_dsn (&obj, &dsn);
            ast_cli(a->fd, "Affected %d rows.  Query executed on handle %d [%s]\n", (int)rows, dsn_num, query->writehandle[dsn_num]);
            executed = 1;
            break;
        }
 
        if (!executed) {
            ast_cli(a->fd, "Failed to execute query.\n");
        }
    } else { /* No execution, just print out the resulting SQL */
        ast_cli(a->fd, "%s\n", ast_str_buffer(sql));
    }
    AST_RWLIST_UNLOCK(&queries);
    return CLI_SUCCESS;
}
 
static struct ast_cli_entry cli_func_odbc[] = {
    AST_CLI_DEFINE(cli_odbc_write, "Test setting a func_odbc function"),
    AST_CLI_DEFINE(cli_odbc_read, "Test reading a func_odbc function"),
};
 
static int load_module(void)
{
    int res = 0;
    struct ast_config *cfg;
    char *catg;
    const char *s;
    struct ast_flags config_flags = { 0 };
 
    res |= ast_custom_function_register(&fetch_function);
    res |= ast_register_application_xml(app_odbcfinish, exec_odbcfinish);
 
    cfg = ast_config_load(config, config_flags);
    if (!cfg || cfg == CONFIG_STATUS_FILEINVALID) {
        ast_log(LOG_NOTICE, "Unable to load config for func_odbc: %s\n", config);
        return AST_MODULE_LOAD_DECLINE;
    }
 
    ast_rwlock_wrlock(&single_db_connection_lock);
    if ((s = ast_variable_retrieve(cfg, "general", "single_db_connection"))) {
        single_db_connection = ast_true(s);
    } else {
        single_db_connection = DEFAULT_SINGLE_DB_CONNECTION;
    }
 
    dsns = NULL;
 
    if (single_db_connection) {
        dsns = ao2_container_alloc_hash(AO2_ALLOC_OPT_LOCK_MUTEX, 0, DSN_BUCKETS,
            dsn_hash, NULL, dsn_cmp);
        if (!dsns) {
            ast_log(LOG_ERROR, "Could not initialize DSN container\n");
            ast_rwlock_unlock(&single_db_connection_lock);
            return AST_MODULE_LOAD_DECLINE;
        }
    }
    ast_rwlock_unlock(&single_db_connection_lock);
 
    AST_RWLIST_WRLOCK(&queries);
    for (catg = ast_category_browse(cfg, NULL);
         catg;
         catg = ast_category_browse(cfg, catg)) {
        struct acf_odbc_query *query = NULL;
        int err;
 
        if (!strcasecmp(catg, "general")) {
            continue;
        }
 
        if ((err = init_acf_query(cfg, catg, &query))) {
            if (err == ENOMEM)
                ast_log(LOG_ERROR, "Out of memory\n");
            else if (err == EINVAL)
                ast_log(LOG_ERROR, "Invalid parameters for category %s\n", catg);
            else
                ast_log(LOG_ERROR, "%s (%d)\n", strerror(err), err);
        } else {
            AST_RWLIST_INSERT_HEAD(&queries, query, list);
            ast_custom_function_register(query->acf);
        }
    }
 
    ast_config_destroy(cfg);
    res |= ast_custom_function_register(&escape_function);
    res |= ast_custom_function_register(&escape_backslashes_function);
    ast_cli_register_multiple(cli_func_odbc, ARRAY_LEN(cli_func_odbc));
 
    AST_RWLIST_UNLOCK(&queries);
    return res;
}
 
static int unload_module(void)
{
    struct acf_odbc_query *query;
    int res = 0;
 
    AST_RWLIST_WRLOCK(&queries);
    while (!AST_RWLIST_EMPTY(&queries)) {
        query = AST_RWLIST_REMOVE_HEAD(&queries, list);
        ast_custom_function_unregister(query->acf);
        free_acf_query(query);
    }
 
    res |= ast_custom_function_unregister(&escape_function);
    res |= ast_custom_function_unregister(&escape_backslashes_function);
    res |= ast_custom_function_unregister(&fetch_function);
    res |= ast_unregister_application(app_odbcfinish);
    ast_cli_unregister_multiple(cli_func_odbc, ARRAY_LEN(cli_func_odbc));
 
    /* Allow any threads waiting for this lock to pass (avoids a race) */
    AST_RWLIST_UNLOCK(&queries);
    usleep(1);
    AST_RWLIST_WRLOCK(&queries);
 
    AST_RWLIST_UNLOCK(&queries);
 
    if (dsns) {
        ao2_ref(dsns, -1);
    }
    return res;
}
 
static int reload(void)
{
    int res = 0;
    struct ast_config *cfg;
    struct acf_odbc_query *oldquery;
    char *catg;
    const char *s;
    struct ast_flags config_flags = { CONFIG_FLAG_FILEUNCHANGED };
 
    cfg = ast_config_load(config, config_flags);
    if (cfg == CONFIG_STATUS_FILEUNCHANGED || cfg == CONFIG_STATUS_FILEINVALID)
        return 0;
 
    ast_rwlock_wrlock(&single_db_connection_lock);
 
    if (dsns) {
        ao2_ref(dsns, -1);
        dsns = NULL;
    }
 
    if (cfg && (s = ast_variable_retrieve(cfg, "general", "single_db_connection"))) {
        single_db_connection = ast_true(s);
    } else {
        single_db_connection = DEFAULT_SINGLE_DB_CONNECTION;
    }
 
    if (single_db_connection) {
        dsns = ao2_container_alloc_hash(AO2_ALLOC_OPT_LOCK_MUTEX, 0, DSN_BUCKETS,
            dsn_hash, NULL, dsn_cmp);
        if (!dsns) {
            ast_log(LOG_ERROR, "Could not initialize DSN container\n");
            ast_rwlock_unlock(&single_db_connection_lock);
            return 0;
        }
    }
    ast_rwlock_unlock(&single_db_connection_lock);
 
    AST_RWLIST_WRLOCK(&queries);
 
    while (!AST_RWLIST_EMPTY(&queries)) {
        oldquery = AST_RWLIST_REMOVE_HEAD(&queries, list);
        ast_custom_function_unregister(oldquery->acf);
        free_acf_query(oldquery);
    }
 
    if (!cfg) {
        ast_log(LOG_WARNING, "Unable to load config for func_odbc: %s\n", config);
        goto reload_out;
    }
 
    for (catg = ast_category_browse(cfg, NULL);
         catg;
         catg = ast_category_browse(cfg, catg)) {
        struct acf_odbc_query *query = NULL;
 
        if (!strcasecmp(catg, "general")) {
            continue;
        }
 
        if (init_acf_query(cfg, catg, &query)) {
            ast_log(LOG_ERROR, "Cannot initialize query %s\n", catg);
        } else {
            AST_RWLIST_INSERT_HEAD(&queries, query, list);
            ast_custom_function_register(query->acf);
        }
    }
 
    ast_config_destroy(cfg);
reload_out:
    AST_RWLIST_UNLOCK(&queries);
    return res;
}
 
/* XXX need to revise usecount - set if query_lock is set */
 
AST_MODULE_INFO(ASTERISK_GPL_KEY, AST_MODFLAG_DEFAULT, "ODBC lookups",
    .support_level = AST_MODULE_SUPPORT_CORE,
    .load = load_module,
    .unload = unload_module,
    .reload = reload,
    .requires = "res_odbc",
);