res_config_odbc.c

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/*
 * Asterisk -- An open source telephony toolkit.
 *
 * Copyright (C) 1999 - 2010, Digium, Inc.
 *
 * Mark Spencer <[email protected]>
 *
 * Copyright (C) 2004 - 2005 Anthony Minessale II <[email protected]>
 *
 * See http://www.asterisk.org for more information about
 * the Asterisk project. Please do not directly contact
 * any of the maintainers of this project for assistance;
 * the project provides a web site, mailing lists and IRC
 * channels for your use.
 *
 * This program is free software, distributed under the terms of
 * the GNU General Public License Version 2. See the LICENSE file
 * at the top of the source tree.
 */

/*! \file
 *
 * \brief odbc+odbc plugin for portable configuration engine
 *
 * \author Mark Spencer <[email protected]>
 * \author Anthony Minessale II <[email protected]>
 *
 * \arg http://www.unixodbc.org
 */

/*** MODULEINFO
   <depend>res_odbc</depend>
   <depend>generic_odbc</depend>
   <support_level>core</support_level>
 ***/

#include "asterisk.h"

#include "asterisk/file.h"
#include "asterisk/channel.h"
#include "asterisk/pbx.h"
#include "asterisk/config.h"
#include "asterisk/module.h"
#include "asterisk/lock.h"
#include "asterisk/res_odbc.h"
#include "asterisk/utils.h"
#include "asterisk/stringfields.h"

/*! Initial SQL query buffer size to allocate. */
#define SQL_BUF_SIZE 1024

AST_THREADSTORAGE(sql_buf);
AST_THREADSTORAGE(rowdata_buf);

struct custom_prepare_struct {
   const char *sql;
   const char *extra;
   AST_DECLARE_STRING_FIELDS(
      AST_STRING_FIELD(encoding)[256];
   );
   const struct ast_variable *fields;
   unsigned long long skip;
};

#define ENCODE_CHUNK(buffer, s) \
   do { \
      char *eptr = buffer; \
      const char *vptr = s; \
      for (; *vptr && eptr < buffer + sizeof(buffer); vptr++) { \
         if (strchr("^;", *vptr)) { \
            /* We use ^XX, instead of %XX because '%' is a special character in SQL */ \
            snprintf(eptr, buffer + sizeof(buffer) - eptr, "^%02hhX", *vptr); \
            eptr += 3; \
         } else { \
            *eptr++ = *vptr; \
         } \
      } \
      if (eptr < buffer + sizeof(buffer)) { \
         *eptr = '\0'; \
      } else { \
         buffer[sizeof(buffer) - 1] = '\0'; \
      } \
   } while(0)

static void decode_chunk(char *chunk)
{
   for (; *chunk; chunk++) {
      if (*chunk == '^' && strchr("0123456789ABCDEF", chunk[1]) && strchr("0123456789ABCDEF", chunk[2])) {
         sscanf(chunk + 1, "%02hhX", (unsigned char *)chunk);
         memmove(chunk + 1, chunk + 3, strlen(chunk + 3) + 1);
      }
   }
}

static inline int is_text(const struct odbc_cache_columns *column)
{
   return column->type == SQL_CHAR || column->type == SQL_VARCHAR || column->type == SQL_LONGVARCHAR
      || column->type == SQL_WCHAR || column->type == SQL_WVARCHAR || column->type == SQL_WLONGVARCHAR;
}

static SQLHSTMT custom_prepare(struct odbc_obj *obj, void *data)
{
   int res, x = 1, count = 0;
   struct custom_prepare_struct *cps = data;
   const struct ast_variable *field;
   char encodebuf[1024];
   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!\n");
      return NULL;
   }

   ast_debug(1, "Skip: %llu; SQL: %s\n", cps->skip, cps->sql);

   res = ast_odbc_prepare(obj, stmt, cps->sql);
   if ((res != SQL_SUCCESS) && (res != SQL_SUCCESS_WITH_INFO)) {
      if (res == SQL_ERROR) {
         ast_odbc_print_errors(SQL_HANDLE_STMT, stmt, "SQL Prepare");
      }
      ast_log(LOG_WARNING, "SQL Prepare failed! [%s]\n", cps->sql);
      SQLFreeHandle (SQL_HANDLE_STMT, stmt);
      return NULL;
   }

   for (field = cps->fields; field; field = field->next) {
      const char *newval = field->value;

      if ((1LL << count++) & cps->skip) {
         ast_debug(1, "Skipping field '%s'='%s' (%llo/%llo)\n", field->name, newval, 1ULL << (count - 1), cps->skip);
         continue;
      }
      ast_debug(1, "Parameter %d ('%s') = '%s'\n", x, field->name, newval);
      if (strchr(newval, ';') || strchr(newval, '^')) {
         ENCODE_CHUNK(encodebuf, newval);
         ast_string_field_set(cps, encoding[x], encodebuf);
         newval = cps->encoding[x];
      }
      SQLBindParameter(stmt, x++, SQL_PARAM_INPUT, SQL_C_CHAR, SQL_CHAR, strlen(newval), 0, (void *)newval, 0, NULL);
   }

   if (!ast_strlen_zero(cps->extra)) {
      const char *newval = cps->extra;
      ast_debug(1, "Parameter %d = '%s'\n", x, newval);
      if (strchr(newval, ';') || strchr(newval, '^')) {
         ENCODE_CHUNK(encodebuf, newval);
         ast_string_field_set(cps, encoding[x], encodebuf);
         newval = cps->encoding[x];
      }
      SQLBindParameter(stmt, x++, SQL_PARAM_INPUT, SQL_C_CHAR, SQL_CHAR, strlen(newval), 0, (void *)newval, 0, NULL);
   }

   return stmt;
}

/*!
 * \brief Excute an SQL query and return ast_variable list
 * \param database
 * \param table
 * \param ap list containing one or more field/operator/value set.
 *
 * Select database and preform query on table, prepare the sql statement
 * Sub-in the values to the prepared statement and execute it. Return results
 * as a ast_variable list.
 *
 * \retval var on success
 * \retval NULL on failure
 */
static struct ast_variable *realtime_odbc(const char *database, const char *table, const struct ast_variable *fields)
{
   struct odbc_obj *obj;
   SQLHSTMT stmt;
   char coltitle[256];
   struct ast_str *sql = ast_str_thread_get(&sql_buf, SQL_BUF_SIZE);
   struct ast_str *rowdata = ast_str_thread_get(&rowdata_buf, 128);
   char *op;
   const struct ast_variable *field = fields;
   char *stringp;
   char *chunk;
   SQLSMALLINT collen;
   int res;
   int x;
   struct ast_variable *var=NULL, *prev=NULL;
   SQLULEN colsize;
   SQLSMALLINT colcount=0;
   SQLSMALLINT datatype;
   SQLSMALLINT decimaldigits;
   SQLSMALLINT nullable;
   SQLLEN indicator;
   struct custom_prepare_struct cps = { .fields = fields, };
   struct ast_flags connected_flag = { RES_ODBC_CONNECTED };

   if (!table || !field || !sql || !rowdata) {
      return NULL;
   }

   obj = ast_odbc_request_obj2(database, connected_flag);
   if (!obj) {
      ast_log(LOG_ERROR, "No database handle available with the name of '%s' (check res_odbc.conf)\n", database);
      return NULL;
   }

   op = !strchr(field->name, ' ') ? " =" : "";
   ast_str_set(&sql, 0, "SELECT * FROM %s WHERE %s%s ?%s", table, field->name, op,
      strcasestr(field->name, "LIKE") && !ast_odbc_backslash_is_escape(obj) ? " ESCAPE '\\\\'" : "");
   while ((field = field->next)) {
      op = !strchr(field->name, ' ') ? " =" : "";
      ast_str_append(&sql, 0, " AND %s%s ?%s", field->name, op,
         strcasestr(field->name, "LIKE") && !ast_odbc_backslash_is_escape(obj) ? " ESCAPE '\\\\'" : "");
   }

   cps.sql = ast_str_buffer(sql);

   if (ast_string_field_init(&cps, 256)) {
      ast_odbc_release_obj(obj);
      return NULL;
   }
   stmt = ast_odbc_prepare_and_execute(obj, custom_prepare, &cps);
   ast_string_field_free_memory(&cps);

   if (!stmt) {
      ast_odbc_release_obj(obj);
      return NULL;
   }

   res = SQLNumResultCols(stmt, &colcount);
   if ((res != SQL_SUCCESS) && (res != SQL_SUCCESS_WITH_INFO)) {
      ast_log(LOG_WARNING, "SQL Column Count error! [%s]\n", ast_str_buffer(sql));
      SQLFreeHandle (SQL_HANDLE_STMT, stmt);
      ast_odbc_release_obj(obj);
      return NULL;
   }

   res = SQLFetch(stmt);
   if (res == SQL_NO_DATA) {
      SQLFreeHandle (SQL_HANDLE_STMT, stmt);
      ast_odbc_release_obj(obj);
      return NULL;
   }
   if ((res != SQL_SUCCESS) && (res != SQL_SUCCESS_WITH_INFO)) {
      ast_log(LOG_WARNING, "SQL Fetch error! [%s]\n", ast_str_buffer(sql));
      SQLFreeHandle (SQL_HANDLE_STMT, stmt);
      ast_odbc_release_obj(obj);
      return NULL;
   }
   for (x = 0; x < colcount; x++) {
      colsize = 0;
      collen = sizeof(coltitle);
      res = SQLDescribeCol(stmt, x + 1, (unsigned char *)coltitle, sizeof(coltitle), &collen,
               &datatype, &colsize, &decimaldigits, &nullable);
      if ((res != SQL_SUCCESS) && (res != SQL_SUCCESS_WITH_INFO)) {
         ast_log(LOG_WARNING, "SQL Describe Column error! [%s]\n", ast_str_buffer(sql));
         if (var)
            ast_variables_destroy(var);
         ast_odbc_release_obj(obj);
         return NULL;
      }

      ast_str_reset(rowdata);
      indicator = 0;

      res = SQLGetData(stmt, x + 1, SQL_CHAR, ast_str_buffer(rowdata), ast_str_size(rowdata), &indicator);
      ast_str_update(rowdata);
      if (indicator == SQL_NULL_DATA) {
         ast_str_reset(rowdata);
      } else if (!ast_str_strlen(rowdata)) {
         /* Because we encode the empty string for a NULL, we will encode
          * actual empty strings as a string containing a single whitespace. */
         ast_str_set(&rowdata, -1, "%s", " ");
      } else if ((res == SQL_SUCCESS) || (res == SQL_SUCCESS_WITH_INFO)) {
         if (indicator != ast_str_strlen(rowdata)) {
            /* If the available space was not enough to contain the row data enlarge and read in the rest */
            ast_str_make_space(&rowdata, indicator + 1);
            res = SQLGetData(stmt, x + 1, SQL_CHAR, ast_str_buffer(rowdata) + ast_str_strlen(rowdata),
               ast_str_size(rowdata) - ast_str_strlen(rowdata), &indicator);
            ast_str_update(rowdata);
         }
      }

      if ((res != SQL_SUCCESS) && (res != SQL_SUCCESS_WITH_INFO)) {
         ast_log(LOG_WARNING, "SQL Get Data error! [%s]\n", ast_str_buffer(sql));
         if (var)
            ast_variables_destroy(var);
         ast_odbc_release_obj(obj);
         return NULL;
      }

      stringp = ast_str_buffer(rowdata);
      if (!strncmp(coltitle, "@", 1)) {
         /* The '@' prefix indicates it's a sorcery extended field.
          * Because ast_load_realtime_fields eliminates empty entries and makes blank (single whitespace)
          * entries empty and keeps them, the empty or NULL values are encoded
          * as a string containing a single whitespace. */
         if (prev) {
            prev->next = ast_variable_new(coltitle, S_OR(stringp," "), "");
            if (prev->next) {
               prev = prev->next;
            }
         } else {
            prev = var = ast_variable_new(coltitle, S_OR(stringp," "), "");
         }
      } else {
         while (stringp) {
            chunk = strsep(&stringp, ";");
            if (!ast_strlen_zero(ast_strip(chunk))) {
               if (strchr(chunk, '^')) {
                  decode_chunk(chunk);
               }
               if (prev) {
                  prev->next = ast_variable_new(coltitle, chunk, "");
                  if (prev->next) {
                     prev = prev->next;
                  }
               } else {
                  prev = var = ast_variable_new(coltitle, chunk, "");
               }
            }
         }
      }
   }

   SQLFreeHandle(SQL_HANDLE_STMT, stmt);
   ast_odbc_release_obj(obj);
   return var;
}

/*!
 * \brief Excute an Select query and return ast_config list
 * \param database
 * \param table
 * \param ap list containing one or more field/operator/value set.
 *
 * Select database and preform query on table, prepare the sql statement
 * Sub-in the values to the prepared statement and execute it.
 * Execute this prepared query against several ODBC connected databases.
 * Return results as an ast_config variable.
 *
 * \retval var on success
 * \retval NULL on failure
 */
static struct ast_config *realtime_multi_odbc(const char *database, const char *table, const struct ast_variable *fields)
{
   struct odbc_obj *obj;
   SQLHSTMT stmt;
   char coltitle[256];
   struct ast_str *sql = ast_str_thread_get(&sql_buf, SQL_BUF_SIZE);
   struct ast_str *rowdata = ast_str_thread_get(&rowdata_buf, 128);
   const char *initfield;
   char *op;
   const struct ast_variable *field = fields;
   char *stringp;
   char *chunk;
   SQLSMALLINT collen;
   int res;
   int x;
   struct ast_variable *var=NULL;
   struct ast_config *cfg=NULL;
   struct ast_category *cat=NULL;
   struct ast_flags connected_flag = { RES_ODBC_CONNECTED };
   SQLULEN colsize;
   SQLSMALLINT colcount=0;
   SQLSMALLINT datatype;
   SQLSMALLINT decimaldigits;
   SQLSMALLINT nullable;
   SQLLEN indicator;
   struct custom_prepare_struct cps = { .fields = fields, };

   if (!table || !field || !sql || !rowdata) {
      return NULL;
   }

   obj = ast_odbc_request_obj2(database, connected_flag);
   if (!obj) {
      return NULL;
   }

   initfield = ast_strdupa(field->name);
   if ((op = strchr(initfield, ' '))) {
      *op = '\0';
   }

   op = !strchr(field->name, ' ') ? " =" : "";
   ast_str_set(&sql, 0, "SELECT * FROM %s WHERE %s%s ?%s", table, field->name, op,
      strcasestr(field->name, "LIKE") && !ast_odbc_backslash_is_escape(obj) ? " ESCAPE '\\\\'" : "");
   while ((field = field->next)) {
      op = !strchr(field->name, ' ') ? " =" : "";
      ast_str_append(&sql, 0, " AND %s%s ?%s", field->name, op,
         strcasestr(field->name, "LIKE") && !ast_odbc_backslash_is_escape(obj) ? " ESCAPE '\\\\'" : "");
   }
   ast_str_append(&sql, 0, " ORDER BY %s", initfield);

   cps.sql = ast_str_buffer(sql);

   if (ast_string_field_init(&cps, 256)) {
      ast_odbc_release_obj(obj);
      return NULL;
   }
   stmt = ast_odbc_prepare_and_execute(obj, custom_prepare, &cps);
   ast_string_field_free_memory(&cps);

   if (!stmt) {
      ast_odbc_release_obj(obj);
      return NULL;
   }

   res = SQLNumResultCols(stmt, &colcount);
   if ((res != SQL_SUCCESS) && (res != SQL_SUCCESS_WITH_INFO)) {
      ast_log(LOG_WARNING, "SQL Column Count error! [%s]\n", ast_str_buffer(sql));
      SQLFreeHandle(SQL_HANDLE_STMT, stmt);
      ast_odbc_release_obj(obj);
      return NULL;
   }

   cfg = ast_config_new();
   if (!cfg) {
      ast_log(LOG_WARNING, "Out of memory!\n");
      SQLFreeHandle(SQL_HANDLE_STMT, stmt);
      ast_odbc_release_obj(obj);
      return NULL;
   }

   while ((res=SQLFetch(stmt)) != SQL_NO_DATA) {
      var = NULL;
      if ((res != SQL_SUCCESS) && (res != SQL_SUCCESS_WITH_INFO)) {
         ast_log(LOG_WARNING, "SQL Fetch error! [%s]\n", ast_str_buffer(sql));
         continue;
      }
      cat = ast_category_new_anonymous();
      if (!cat) {
         continue;
      }
      for (x=0;x<colcount;x++) {
         colsize = 0;
         collen = sizeof(coltitle);
         res = SQLDescribeCol(stmt, x + 1, (unsigned char *)coltitle, sizeof(coltitle), &collen,
                  &datatype, &colsize, &decimaldigits, &nullable);
         if ((res != SQL_SUCCESS) && (res != SQL_SUCCESS_WITH_INFO)) {
            ast_log(LOG_WARNING, "SQL Describe Column error! [%s]\n", ast_str_buffer(sql));
            ast_category_destroy(cat);
            goto next_sql_fetch;
         }

         ast_str_reset(rowdata);
         indicator = 0;

         res = SQLGetData(stmt, x + 1, SQL_CHAR, ast_str_buffer(rowdata), ast_str_size(rowdata), &indicator);
         ast_str_update(rowdata);
         if (indicator == SQL_NULL_DATA) {
            continue;
         }

         if ((res == SQL_SUCCESS) || (res == SQL_SUCCESS_WITH_INFO)) {
            if (indicator != ast_str_strlen(rowdata)) {
               /* If the available space was not enough to contain the row data enlarge and read in the rest */
               ast_str_make_space(&rowdata, indicator + 1);
               res = SQLGetData(stmt, x + 1, SQL_CHAR, ast_str_buffer(rowdata) + ast_str_strlen(rowdata),
                  ast_str_size(rowdata) - ast_str_strlen(rowdata), &indicator);
               ast_str_update(rowdata);
            }
         }

         if ((res != SQL_SUCCESS) && (res != SQL_SUCCESS_WITH_INFO)) {
            ast_log(LOG_WARNING, "SQL Get Data error! [%s]\n", ast_str_buffer(sql));
            ast_category_destroy(cat);
            goto next_sql_fetch;
         }
         stringp = ast_str_buffer(rowdata);
         if (!strncmp(coltitle, "@", 1)) {
            /* The '@' prefix indicates it's a sorcery extended field.
             * Because ast_load_realtime_fields eliminates empty entries and makes blank (single whitespace)
             * entries empty and keeps them, the empty or NULL values are encoded
             * as a string containing a single whitespace. */
            var = ast_variable_new(coltitle, S_OR(stringp," "), "");
            ast_variable_append(cat, var);
         } else {
            while (stringp) {
               chunk = strsep(&stringp, ";");
               if (!ast_strlen_zero(ast_strip(chunk))) {
                  if (strchr(chunk, '^')) {
                     decode_chunk(chunk);
                  }
                  if (!strcmp(initfield, coltitle)) {
                     ast_category_rename(cat, chunk);
                  }
                  var = ast_variable_new(coltitle, chunk, "");
                  ast_variable_append(cat, var);
               }
            }
         }
      }
      ast_category_append(cfg, cat);
next_sql_fetch:;
   }

   SQLFreeHandle(SQL_HANDLE_STMT, stmt);
   ast_odbc_release_obj(obj);
   return cfg;
}

/*!
 * \brief Excute an UPDATE query
 * \param database
 * \param table
 * \param keyfield where clause field
 * \param lookup value of field for where clause
 * \param ap list containing one or more field/value set(s).
 *
 * Update a database table, prepare the sql statement using keyfield and lookup
 * control the number of records to change. All values to be changed are stored in ap list.
 * Sub-in the values to the prepared statement and execute it.
 *
 * \retval number of rows affected
 * \retval -1 on failure
 */
static int update_odbc(const char *database, const char *table, const char *keyfield, const char *lookup, const struct ast_variable *fields)
{
   struct odbc_obj *obj;
   SQLHSTMT stmt;
   SQLLEN rowcount=0;
   struct ast_str *sql = ast_str_thread_get(&sql_buf, SQL_BUF_SIZE);
   const struct ast_variable *field = fields;
   int res, count = 0, paramcount = 0;
   struct custom_prepare_struct cps = { .extra = lookup, .fields = fields, };
   struct odbc_cache_tables *tableptr;
   struct odbc_cache_columns *column = NULL;
   struct ast_flags connected_flag = { RES_ODBC_CONNECTED };

   if (!table || !field || !keyfield || !sql) {
      return -1;
   }

   tableptr = ast_odbc_find_table(database, table);
   if (!(obj = ast_odbc_request_obj2(database, connected_flag))) {
      ast_odbc_release_table(tableptr);
      return -1;
   }

   if (tableptr && !ast_odbc_find_column(tableptr, keyfield)) {
      ast_log(LOG_WARNING, "Key field '%s' does not exist in table '%s@%s'.  Update will fail\n", keyfield, table, database);
   }

   ast_str_set(&sql, 0, "UPDATE %s SET ", table);
   while (field) {
      if ((tableptr && (column = ast_odbc_find_column(tableptr, field->name))) || count >= 64) {
         if (paramcount++) {
            ast_str_append(&sql, 0, ", ");
         }
         /* NULL test for non-text columns */
         if (count < 64 && ast_strlen_zero(field->value) && column->nullable && !is_text(column)) {
            ast_str_append(&sql, 0, "%s=NULL", field->name);
            cps.skip |= (1LL << count);
         } else {
            /* Value is not an empty string, or column is of text type, or we couldn't fit any more into cps.skip (count >= 64 ?!). */
            ast_str_append(&sql, 0, "%s=?", field->name);
         }
      } else { /* the column does not exist in the table */
         cps.skip |= (1LL << count);
      }
      ++count;
      field = field->next;
   }
   ast_str_append(&sql, 0, " WHERE %s=?", keyfield);
   ast_odbc_release_table(tableptr);

   cps.sql = ast_str_buffer(sql);

   if (ast_string_field_init(&cps, 256)) {
      ast_odbc_release_obj(obj);
      return -1;
   }
   stmt = ast_odbc_prepare_and_execute(obj, custom_prepare, &cps);
   ast_string_field_free_memory(&cps);

   if (!stmt) {
      ast_odbc_release_obj(obj);
      return -1;
   }

   res = SQLRowCount(stmt, &rowcount);
   SQLFreeHandle (SQL_HANDLE_STMT, stmt);
   ast_odbc_release_obj(obj);

   if ((res != SQL_SUCCESS) && (res != SQL_SUCCESS_WITH_INFO)) {
      ast_log(LOG_WARNING, "SQL Row Count error! [%s]\n", ast_str_buffer(sql));
      return -1;
   }

   if (rowcount >= 0) {
      return (int) rowcount;
   }

   return -1;
}

struct update2_prepare_struct {
   const char *database;
   const char *table;
   const struct ast_variable *lookup_fields;
   const struct ast_variable *update_fields;
   struct odbc_cache_tables *tableptr;
};

static SQLHSTMT update2_prepare(struct odbc_obj *obj, void *data)
{
   int res, x = 1, first = 1;
   struct update2_prepare_struct *ups = data;
   const struct ast_variable *field;
   struct ast_str *sql = ast_str_thread_get(&sql_buf, SQL_BUF_SIZE);
   SQLHSTMT stmt;

   if (!sql) {
      return NULL;
   }

   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!\n");
      return NULL;
   }

   ast_str_set(&sql, 0, "UPDATE %s SET ", ups->table);

   for (field = ups->update_fields; field; field = field->next) {
      if (ast_odbc_find_column(ups->tableptr, field->name)) {
         ast_str_append(&sql, 0, "%s%s=? ", first ? "" : ", ", field->name);
         SQLBindParameter(stmt, x++, SQL_PARAM_INPUT, SQL_C_CHAR, SQL_CHAR, strlen(field->name), 0, (void *)field->value, 0, NULL);
         first = 0;
      } else {
         ast_log(LOG_NOTICE, "Not updating column '%s' in '%s@%s' because that column does not exist!\n", field->name, ups->table, ups->database);
      }
   }

   ast_str_append(&sql, 0, "WHERE");
   first = 1;

   for (field = ups->lookup_fields; field; field = field->next) {
      if (!ast_odbc_find_column(ups->tableptr, field->name)) {
         ast_log(LOG_ERROR, "One or more of the criteria columns '%s' on '%s@%s' for this update does not exist!\n", field->name, ups->table, ups->database);
         SQLFreeHandle(SQL_HANDLE_STMT, stmt);
         return NULL;
      }
      ast_str_append(&sql, 0, "%s %s=?", first ? "" : " AND", field->name);
      SQLBindParameter(stmt, x++, SQL_PARAM_INPUT, SQL_C_CHAR, SQL_CHAR, strlen(field->value), 0, (void *)field->value, 0, NULL);
      first = 0;
   }

   res = ast_odbc_prepare(obj, stmt, ast_str_buffer(sql));
   if ((res != SQL_SUCCESS) && (res != SQL_SUCCESS_WITH_INFO)) {
      if (res == SQL_ERROR) {
         ast_odbc_print_errors(SQL_HANDLE_STMT, stmt, "SQL Prepare");
      }
      ast_log(LOG_WARNING, "SQL Prepare failed! [%s]\n", ast_str_buffer(sql));
      SQLFreeHandle(SQL_HANDLE_STMT, stmt);
      return NULL;
   }

   return stmt;
}

/*!
 * \brief Execute an UPDATE query
 * \param database
 * \param table
 * \param ap list containing one or more field/value set(s).
 *
 * Update a database table, preparing the sql statement from a list of
 * key/value pairs specified in ap.  The lookup pairs are specified first
 * and are separated from the update pairs by a sentinel value.
 * Sub-in the values to the prepared statement and execute it.
 *
 * \retval number of rows affected
 * \retval -1 on failure
*/
static int update2_odbc(const char *database, const char *table, const struct ast_variable *lookup_fields, const struct ast_variable *update_fields)
{
   struct odbc_obj *obj;
   SQLHSTMT stmt;
   struct update2_prepare_struct ups = {
      .database = database,
      .table = table,
      .lookup_fields = lookup_fields,
      .update_fields = update_fields,
   };
   struct ast_str *sql;
   int res;
   SQLLEN rowcount = 0;

   ups.tableptr = ast_odbc_find_table(database, table);
   if (!ups.tableptr) {
      ast_log(LOG_ERROR, "Could not retrieve metadata for table '%s@%s'. Update will fail!\n", table, database);
      return -1;
   }

   if (!(obj = ast_odbc_request_obj(database, 0))) {
      ast_odbc_release_table(ups.tableptr);
      return -1;
   }

   if (!(stmt = ast_odbc_prepare_and_execute(obj, update2_prepare, &ups))) {
      ast_odbc_release_obj(obj);
      ast_odbc_release_table(ups.tableptr);
      return -1;
   }

   /* We don't need the table anymore */
   ast_odbc_release_table(ups.tableptr);

   res = SQLRowCount(stmt, &rowcount);
   SQLFreeHandle(SQL_HANDLE_STMT, stmt);
   ast_odbc_release_obj(obj);

   if ((res != SQL_SUCCESS) && (res != SQL_SUCCESS_WITH_INFO)) {
      /* Since only a single thread can access this memory, we can retrieve what would otherwise be lost. */
      sql = ast_str_thread_get(&sql_buf, SQL_BUF_SIZE);
      ast_assert(sql != NULL);
      ast_log(LOG_WARNING, "SQL Row Count error! [%s]\n", ast_str_buffer(sql));
      return -1;
   }

   if (rowcount >= 0) {
      return (int) rowcount;
   }

   return -1;
}

/*!
 * \brief Excute an INSERT query
 * \param database
 * \param table
 * \param ap list containing one or more field/value set(s)
 *
 * Insert a new record into database table, prepare the sql statement.
 * All values to be changed are stored in ap list.
 * Sub-in the values to the prepared statement and execute it.
 *
 * \retval number of rows affected
 * \retval -1 on failure
 */
static int store_odbc(const char *database, const char *table, const struct ast_variable *fields)
{
   struct odbc_obj *obj;
   SQLHSTMT stmt;
   SQLLEN rowcount=0;
   const struct ast_variable *field = fields;
   struct ast_str *keys;
   struct ast_str *vals;
   struct ast_str *sql = ast_str_thread_get(&sql_buf, SQL_BUF_SIZE);
   int res;
   struct custom_prepare_struct cps = { .fields = fields, };
   struct ast_flags connected_flag = { RES_ODBC_CONNECTED };

   keys = ast_str_create(SQL_BUF_SIZE / 2);
   vals = ast_str_create(SQL_BUF_SIZE / 4);
   if (!table || !field || !keys || !vals || !sql) {
      ast_free(vals);
      ast_free(keys);
      return -1;
   }

   obj = ast_odbc_request_obj2(database, connected_flag);
   if (!obj) {
      ast_free(vals);
      ast_free(keys);
      return -1;
   }

   ast_str_set(&keys, 0, "%s", field->name);
   ast_str_set(&vals, 0, "?");
   while ((field = field->next)) {
      ast_str_append(&keys, 0, ", %s", field->name);
      ast_str_append(&vals, 0, ", ?");
   }
   ast_str_set(&sql, 0, "INSERT INTO %s (%s) VALUES (%s)",
      table, ast_str_buffer(keys), ast_str_buffer(vals));

   ast_free(vals);
   ast_free(keys);
   cps.sql = ast_str_buffer(sql);

   if (ast_string_field_init(&cps, 256)) {
      ast_odbc_release_obj(obj);
      return -1;
   }
   stmt = ast_odbc_prepare_and_execute(obj, custom_prepare, &cps);
   ast_string_field_free_memory(&cps);

   if (!stmt) {
      ast_odbc_release_obj(obj);
      return -1;
   }

   res = SQLRowCount(stmt, &rowcount);
   SQLFreeHandle (SQL_HANDLE_STMT, stmt);
   ast_odbc_release_obj(obj);

   if ((res != SQL_SUCCESS) && (res != SQL_SUCCESS_WITH_INFO)) {
      ast_log(LOG_WARNING, "SQL Row Count error! [%s]\n", ast_str_buffer(sql));
      return -1;
   }

   if (rowcount >= 0)
      return (int)rowcount;

   return -1;
}

/*!
 * \brief Excute an DELETE query
 * \param database
 * \param table
 * \param keyfield where clause field
 * \param lookup value of field for where clause
 * \param ap list containing one or more field/value set(s)
 *
 * Delete a row from a database table, prepare the sql statement using keyfield and lookup
 * control the number of records to change. Additional params to match rows are stored in ap list.
 * Sub-in the values to the prepared statement and execute it.
 *
 * \retval number of rows affected
 * \retval -1 on failure
 */
static int destroy_odbc(const char *database, const char *table, const char *keyfield, const char *lookup, const struct ast_variable *fields)
{
   struct odbc_obj *obj;
   SQLHSTMT stmt;
   SQLLEN rowcount=0;
   struct ast_str *sql = ast_str_thread_get(&sql_buf, SQL_BUF_SIZE);
   const struct ast_variable *field;
   int res;
   struct custom_prepare_struct cps = { .extra = lookup, .fields = fields, };
   struct ast_flags connected_flag = { RES_ODBC_CONNECTED };

   if (!table || !sql) {
      return -1;
   }

   obj = ast_odbc_request_obj2(database, connected_flag);
   if (!obj) {
      return -1;
   }

   ast_str_set(&sql, 0, "DELETE FROM %s WHERE ", table);
   for (field = fields; field; field = field->next) {
      ast_str_append(&sql, 0, "%s=? AND ", field->name);
   }
   ast_str_append(&sql, 0, "%s=?", keyfield);

   cps.sql = ast_str_buffer(sql);

   if (ast_string_field_init(&cps, 256)) {
      ast_odbc_release_obj(obj);
      return -1;
   }
   stmt = ast_odbc_prepare_and_execute(obj, custom_prepare, &cps);
   ast_string_field_free_memory(&cps);

   if (!stmt) {
      ast_odbc_release_obj(obj);
      return -1;
   }

   res = SQLRowCount(stmt, &rowcount);
   SQLFreeHandle (SQL_HANDLE_STMT, stmt);
   ast_odbc_release_obj(obj);

   if ((res != SQL_SUCCESS) && (res != SQL_SUCCESS_WITH_INFO)) {
      ast_log(LOG_WARNING, "SQL Row Count error! [%s]\n", ast_str_buffer(sql));
      return -1;
   }

   if (rowcount >= 0)
      return (int)rowcount;

   return -1;
}

struct config_odbc_obj {
   char *sql;
   unsigned long cat_metric;
   char category[128];
   char var_name[128];
   char *var_val;
   unsigned long var_val_size;
   SQLLEN err;
};


static SQLHSTMT length_determination_odbc_prepare(struct odbc_obj *obj, void *data)
{
   struct config_odbc_obj *q = data;
   SQLHSTMT sth;
   int res;

   res = SQLAllocHandle(SQL_HANDLE_STMT, obj->con, &sth);
   if ((res != SQL_SUCCESS) && (res != SQL_SUCCESS_WITH_INFO)) {
      ast_verb(4, "Failure in AllocStatement %d\n", res);
      return NULL;
   }

   res = ast_odbc_prepare(obj, sth, q->sql);
   if ((res != SQL_SUCCESS) && (res != SQL_SUCCESS_WITH_INFO)) {
      ast_verb(4, "Error in PREPARE %d\n", res);
      SQLFreeHandle(SQL_HANDLE_STMT, sth);
      return NULL;
   }

   SQLBindCol(sth, 1, SQL_C_ULONG, &q->var_val_size, sizeof(q->var_val_size), &q->err);

   return sth;
}

static SQLHSTMT config_odbc_prepare(struct odbc_obj *obj, void *data)
{
   struct config_odbc_obj *q = data;
   SQLHSTMT sth;
   int res;

   res = SQLAllocHandle(SQL_HANDLE_STMT, obj->con, &sth);
   if ((res != SQL_SUCCESS) && (res != SQL_SUCCESS_WITH_INFO)) {
      ast_verb(4, "Failure in AllocStatement %d\n", res);
      return NULL;
   }

   res = ast_odbc_prepare(obj, sth, q->sql);
   if ((res != SQL_SUCCESS) && (res != SQL_SUCCESS_WITH_INFO)) {
      ast_verb(4, "Error in PREPARE %d\n", res);
      SQLFreeHandle(SQL_HANDLE_STMT, sth);
      return NULL;
   }

   SQLBindCol(sth, 1, SQL_C_ULONG, &q->cat_metric, sizeof(q->cat_metric), &q->err);
   SQLBindCol(sth, 2, SQL_C_CHAR, q->category, sizeof(q->category), &q->err);
   SQLBindCol(sth, 3, SQL_C_CHAR, q->var_name, sizeof(q->var_name), &q->err);
   SQLBindCol(sth, 4, SQL_C_CHAR, q->var_val, q->var_val_size, &q->err);

   return sth;
}

static struct ast_config *config_odbc(const char *database, const char *table, const char *file, struct ast_config *cfg, struct ast_flags flags, const char *sugg_incl, const char *who_asked)
{
   struct ast_variable *new_v;
   struct ast_category *cur_cat;
   int res = 0;
   struct odbc_obj *obj;
   struct ast_str *sql = ast_str_thread_get(&sql_buf, SQL_BUF_SIZE);
   unsigned int last_cat_metric = 0;
   SQLSMALLINT rowcount = 0;
   SQLHSTMT stmt;
   char last[128] = "";
   struct config_odbc_obj q;
   struct ast_flags loader_flags = { 0 };
   struct ast_flags connected_flag = { RES_ODBC_CONNECTED };

   memset(&q, 0, sizeof(q));

   if (!file || !strcmp (file, "res_config_odbc.conf") || !sql) {
      return NULL;      /* cant configure myself with myself ! */
   }

   obj = ast_odbc_request_obj2(database, connected_flag);
   if (!obj)
      return NULL;

   ast_str_set(&sql, 0, "SELECT MAX(LENGTH(var_val)) FROM %s WHERE filename='%s'",
      table, file);
   q.sql = ast_str_buffer(sql);

   stmt = ast_odbc_prepare_and_execute(obj, length_determination_odbc_prepare, &q);
   if (!stmt) {
      ast_log(LOG_WARNING, "SQL select error! [%s]\n", ast_str_buffer(sql));
      ast_odbc_release_obj(obj);
      return NULL;
   }

   res = SQLNumResultCols(stmt, &rowcount);

   if ((res != SQL_SUCCESS) && (res != SQL_SUCCESS_WITH_INFO)) {
      ast_log(LOG_WARNING, "SQL NumResultCols error! [%s]\n", ast_str_buffer(sql));
      SQLFreeHandle(SQL_HANDLE_STMT, stmt);
      ast_odbc_release_obj(obj);
      return NULL;
   }

   if (!rowcount) {
      ast_log(LOG_NOTICE, "found nothing\n");
      ast_odbc_release_obj(obj);
      return cfg;
   }

   /* There will be only one result for this, the maximum length of a variable value */
   if (SQLFetch(stmt) == SQL_NO_DATA) {
      ast_log(LOG_NOTICE, "Failed to determine maximum length of a configuration value\n");
      SQLFreeHandle(SQL_HANDLE_STMT, stmt);
      ast_odbc_release_obj(obj);
      return NULL;
   }

   /* Reset stuff to a fresh state for the actual query which will retrieve all configuration */
   SQLFreeHandle(SQL_HANDLE_STMT, stmt);

   ast_str_set(&sql, 0, "SELECT cat_metric, category, var_name, var_val FROM %s ", table);
   ast_str_append(&sql, 0, "WHERE filename='%s' AND commented=0 ", file);
   ast_str_append(&sql, 0, "ORDER BY cat_metric DESC, var_metric ASC, category, var_name ");
   q.sql = ast_str_buffer(sql);

   q.var_val_size += 1;
   q.var_val = ast_malloc(q.var_val_size);
   if (!q.var_val) {
      ast_log(LOG_WARNING, "Could not create buffer for reading in configuration values for '%s'\n", file);
      ast_odbc_release_obj(obj);
      return NULL;
   }

   stmt = ast_odbc_prepare_and_execute(obj, config_odbc_prepare, &q);
   if (!stmt) {
      ast_log(LOG_WARNING, "SQL select error! [%s]\n", ast_str_buffer(sql));
      ast_odbc_release_obj(obj);
      ast_free(q.var_val);
      return NULL;
   }

   res = SQLNumResultCols(stmt, &rowcount);

   if ((res != SQL_SUCCESS) && (res != SQL_SUCCESS_WITH_INFO)) {
      ast_log(LOG_WARNING, "SQL NumResultCols error! [%s]\n", ast_str_buffer(sql));
      SQLFreeHandle(SQL_HANDLE_STMT, stmt);
      ast_odbc_release_obj(obj);
      ast_free(q.var_val);
      return NULL;
   }

   if (!rowcount) {
      ast_log(LOG_NOTICE, "found nothing\n");
      ast_odbc_release_obj(obj);
      ast_free(q.var_val);
      return cfg;
   }

   cur_cat = ast_config_get_current_category(cfg);

   while ((res = SQLFetch(stmt)) != SQL_NO_DATA) {
      if (!strcmp (q.var_name, "#include")) {
         if (!ast_config_internal_load(q.var_val, cfg, loader_flags, "", who_asked)) {
            SQLFreeHandle(SQL_HANDLE_STMT, stmt);
            ast_odbc_release_obj(obj);
            ast_free(q.var_val);
            return NULL;
         }
         continue;
      }
      if (strcmp(last, q.category) || last_cat_metric != q.cat_metric) {
         cur_cat = ast_category_new_dynamic(q.category);
         if (!cur_cat) {
            break;
         }
         strcpy(last, q.category);
         last_cat_metric   = q.cat_metric;
         ast_category_append(cfg, cur_cat);
      }

      new_v = ast_variable_new(q.var_name, q.var_val, "");
      ast_variable_append(cur_cat, new_v);
   }

   SQLFreeHandle(SQL_HANDLE_STMT, stmt);
   ast_odbc_release_obj(obj);
   ast_free(q.var_val);
   return cfg;
}

#define warn_length(col, size)   ast_log(LOG_WARNING, "Realtime table %s@%s: column '%s' is not long enough to contain realtime data (needs %d)\n", table, database, col->name, size)
#define warn_type(col, type)  ast_log(LOG_WARNING, "Realtime table %s@%s: column '%s' is of the incorrect type (%d) to contain the required realtime data\n", table, database, col->name, col->type)

static int require_odbc(const char *database, const char *table, va_list ap)
{
   struct odbc_cache_tables *tableptr = ast_odbc_find_table(database, table);
   struct odbc_cache_columns *col;
   char *elm;
   int type, size;

   if (!tableptr) {
      return -1;
   }

   while ((elm = va_arg(ap, char *))) {
      type = va_arg(ap, require_type);
      size = va_arg(ap, int);
      /* Check if the field matches the criteria */
      AST_RWLIST_TRAVERSE(&tableptr->columns, col, list) {
         if (strcmp(col->name, elm) == 0) {
            /* Type check, first.  Some fields are more particular than others */
            switch (col->type) {
            case SQL_CHAR:
            case SQL_VARCHAR:
            case SQL_LONGVARCHAR:
#ifdef HAVE_ODBC_WCHAR
            case SQL_WCHAR:
            case SQL_WVARCHAR:
            case SQL_WLONGVARCHAR:
#endif
            case SQL_BINARY:
            case SQL_VARBINARY:
            case SQL_LONGVARBINARY:
            case SQL_GUID:
#define CHECK_SIZE(n) \
                  if (col->size < n) {      \
                     warn_length(col, n);  \
                  }                         \
                  break;
               switch (type) {
               case RQ_UINTEGER1: CHECK_SIZE(3)  /*         255 */
               case RQ_INTEGER1:  CHECK_SIZE(4)  /*        -128 */
               case RQ_UINTEGER2: CHECK_SIZE(5)  /*       65535 */
               case RQ_INTEGER2:  CHECK_SIZE(6)  /*      -32768 */
               case RQ_UINTEGER3:                /*    16777215 */
               case RQ_INTEGER3:  CHECK_SIZE(8)  /*    -8388608 */
               case RQ_DATE:                     /*  2008-06-09 */
               case RQ_UINTEGER4: CHECK_SIZE(10) /*  4200000000 */
               case RQ_INTEGER4:  CHECK_SIZE(11) /* -2100000000 */
               case RQ_DATETIME:                 /* 2008-06-09 16:03:47 */
               case RQ_UINTEGER8: CHECK_SIZE(19) /* trust me    */
               case RQ_INTEGER8:  CHECK_SIZE(20) /* ditto       */
               case RQ_FLOAT:
               case RQ_CHAR:      CHECK_SIZE(size)
               }
#undef CHECK_SIZE
               break;
            case SQL_TYPE_DATE:
               if (type != RQ_DATE) {
                  warn_type(col, type);
               }
               break;
            case SQL_TYPE_TIMESTAMP:
            case SQL_TIMESTAMP:
               if (type != RQ_DATE && type != RQ_DATETIME) {
                  warn_type(col, type);
               }
               break;
            case SQL_BIT:
               warn_length(col, size);
               break;
#define WARN_TYPE_OR_LENGTH(n)   \
                  if (!ast_rq_is_int(type)) {  \
                     warn_type(col, type);    \
                  } else {                     \
                     warn_length(col, n);  \
                  }
            case SQL_TINYINT:
               if (type != RQ_UINTEGER1) {
                  WARN_TYPE_OR_LENGTH(size)
               }
               break;
            case SQL_C_STINYINT:
               if (type != RQ_INTEGER1) {
                  WARN_TYPE_OR_LENGTH(size)
               }
               break;
            case SQL_C_USHORT:
               if (type != RQ_UINTEGER1 && type != RQ_INTEGER1 && type != RQ_UINTEGER2) {
                  WARN_TYPE_OR_LENGTH(size)
               }
               break;
            case SQL_SMALLINT:
            case SQL_C_SSHORT:
               if (type != RQ_UINTEGER1 && type != RQ_INTEGER1 && type != RQ_INTEGER2) {
                  WARN_TYPE_OR_LENGTH(size)
               }
               break;
            case SQL_C_ULONG:
               if (type != RQ_UINTEGER1 && type != RQ_INTEGER1 &&
                  type != RQ_UINTEGER2 && type != RQ_INTEGER2 &&
                  type != RQ_UINTEGER3 && type != RQ_INTEGER3 &&
                  type != RQ_INTEGER4) {
                  WARN_TYPE_OR_LENGTH(size)
               }
               break;
            case SQL_INTEGER:
            case SQL_C_SLONG:
               if (type != RQ_UINTEGER1 && type != RQ_INTEGER1 &&
                  type != RQ_UINTEGER2 && type != RQ_INTEGER2 &&
                  type != RQ_UINTEGER3 && type != RQ_INTEGER3 &&
                  type != RQ_INTEGER4) {
                  WARN_TYPE_OR_LENGTH(size)
               }
               break;
            case SQL_C_UBIGINT:
               if (type != RQ_UINTEGER1 && type != RQ_INTEGER1 &&
                  type != RQ_UINTEGER2 && type != RQ_INTEGER2 &&
                  type != RQ_UINTEGER3 && type != RQ_INTEGER3 &&
                  type != RQ_UINTEGER4 && type != RQ_INTEGER4 &&
                  type != RQ_INTEGER8) {
                  WARN_TYPE_OR_LENGTH(size)
               }
               break;
            case SQL_BIGINT:
            case SQL_C_SBIGINT:
               if (type != RQ_UINTEGER1 && type != RQ_INTEGER1 &&
                  type != RQ_UINTEGER2 && type != RQ_INTEGER2 &&
                  type != RQ_UINTEGER3 && type != RQ_INTEGER3 &&
                  type != RQ_UINTEGER4 && type != RQ_INTEGER4 &&
                  type != RQ_INTEGER8) {
                  WARN_TYPE_OR_LENGTH(size)
               }
               break;
#undef WARN_TYPE_OR_LENGTH
            case SQL_NUMERIC:
            case SQL_DECIMAL:
            case SQL_FLOAT:
            case SQL_REAL:
            case SQL_DOUBLE:
               if (!ast_rq_is_int(type) && type != RQ_FLOAT) {
                  warn_type(col, type);
               }
               break;
            default:
               ast_log(LOG_WARNING, "Realtime table %s@%s: column type (%d) unrecognized for column '%s'\n", table, database, col->type, elm);
            }
            break;
         }
      }
      if (!col) {
         ast_log(LOG_WARNING, "Realtime table %s@%s requires column '%s', but that column does not exist!\n", table, database, elm);
      }
   }
   AST_RWLIST_UNLOCK(&tableptr->columns);
   return 0;
}
#undef warn_length
#undef warn_type

static int unload_odbc(const char *a, const char *b)
{
   return ast_odbc_clear_cache(a, b);
}

static struct ast_config_engine odbc_engine = {
   .name = "odbc",
   .load_func = config_odbc,
   .realtime_func = realtime_odbc,
   .realtime_multi_func = realtime_multi_odbc,
   .store_func = store_odbc,
   .destroy_func = destroy_odbc,
   .update_func = update_odbc,
   .update2_func = update2_odbc,
   .require_func = require_odbc,
   .unload_func = unload_odbc,
};

static int unload_module (void)
{
   ast_config_engine_deregister(&odbc_engine);

   return 0;
}

static int load_module (void)
{
   ast_config_engine_register(&odbc_engine);

   return 0;
}

static int reload_module(void)
{
   return 0;
}

AST_MODULE_INFO(ASTERISK_GPL_KEY, AST_MODFLAG_LOAD_ORDER, "Realtime ODBC configuration",
   .support_level = AST_MODULE_SUPPORT_CORE,
   .load = load_module,
   .unload = unload_module,
   .reload = reload_module,
   .load_pri = AST_MODPRI_REALTIME_DRIVER,
   .requires = "extconfig,res_odbc",
);