Viewing file:  apr_dbd.h (24.07 KB) -rw-rw-rw-
Select action/file-type:
 (+) |  (+) |  (+) | Code (+) | Session (+) |  (+) | SDB (+) |  (+) |  (+) |  (+) |  (+) |  (+) |
/* Licensed to the Apache Software Foundation (ASF) under one or more
* contributor license agreements. See the NOTICE file distributed with
* this work for additional information regarding copyright ownership.
* The ASF licenses this file to You under the Apache License, Version 2.0
* (the "License"); you may not use this file except in compliance with
* the License. You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
/* Overview of what this is and does:
* http://www.apache.org/~niq/dbd.html
*/
#ifndef APR_DBD_H
#define APR_DBD_H
#include "apu.h"
#include "apr_pools.h"
#ifdef __cplusplus
extern "C" {
#endif
/**
* @file apr_dbd.h
* @brief APR-UTIL DBD library
*/
/**
* @defgroup APR_Util_DBD DBD routines
* @ingroup APR_Util
* @{
*/
/**
* Mapping of C to SQL types, used for prepared statements.
* @remarks
* For apr_dbd_p[v]query/select functions, in and out parameters are always
* const char * (i.e. regular nul terminated strings). LOB types are passed
* with four (4) arguments: payload, length, table and column, all as const
* char *, where table and column are reserved for future use by Oracle.
* @remarks
* For apr_dbd_p[v]bquery/select functions, in and out parameters are
* described next to each enumeration constant and are generally native binary
* types or some APR data type. LOB types are passed with four (4) arguments:
* payload (char*), length (apr_size_t*), table (char*) and column (char*).
* Table and column are reserved for future use by Oracle.
*/
typedef enum {
APR_DBD_TYPE_NONE,
APR_DBD_TYPE_TINY, /**< \%hhd : in, out: char* */
APR_DBD_TYPE_UTINY, /**< \%hhu : in, out: unsigned char* */
APR_DBD_TYPE_SHORT, /**< \%hd : in, out: short* */
APR_DBD_TYPE_USHORT, /**< \%hu : in, out: unsigned short* */
APR_DBD_TYPE_INT, /**< \%d : in, out: int* */
APR_DBD_TYPE_UINT, /**< \%u : in, out: unsigned int* */
APR_DBD_TYPE_LONG, /**< \%ld : in, out: long* */
APR_DBD_TYPE_ULONG, /**< \%lu : in, out: unsigned long* */
APR_DBD_TYPE_LONGLONG, /**< \%lld : in, out: apr_int64_t* */
APR_DBD_TYPE_ULONGLONG, /**< \%llu : in, out: apr_uint64_t* */
APR_DBD_TYPE_FLOAT, /**< \%f : in, out: float* */
APR_DBD_TYPE_DOUBLE, /**< \%lf : in, out: double* */
APR_DBD_TYPE_STRING, /**< \%s : in: char*, out: char** */
APR_DBD_TYPE_TEXT, /**< \%pDt : in: char*, out: char** */
APR_DBD_TYPE_TIME, /**< \%pDi : in: char*, out: char** */
APR_DBD_TYPE_DATE, /**< \%pDd : in: char*, out: char** */
APR_DBD_TYPE_DATETIME, /**< \%pDa : in: char*, out: char** */
APR_DBD_TYPE_TIMESTAMP, /**< \%pDs : in: char*, out: char** */
APR_DBD_TYPE_ZTIMESTAMP, /**< \%pDz : in: char*, out: char** */
APR_DBD_TYPE_BLOB, /**< \%pDb : in: char* apr_size_t* char* char*, out: apr_bucket_brigade* */
APR_DBD_TYPE_CLOB, /**< \%pDc : in: char* apr_size_t* char* char*, out: apr_bucket_brigade* */
APR_DBD_TYPE_NULL /**< \%pDn : in: void*, out: void** */
} apr_dbd_type_e;
/* These are opaque structs. Instantiation is up to each backend */
typedef struct apr_dbd_driver_t apr_dbd_driver_t;
typedef struct apr_dbd_t apr_dbd_t;
typedef struct apr_dbd_transaction_t apr_dbd_transaction_t;
typedef struct apr_dbd_results_t apr_dbd_results_t;
typedef struct apr_dbd_row_t apr_dbd_row_t;
typedef struct apr_dbd_prepared_t apr_dbd_prepared_t;
/** apr_dbd_init: perform once-only initialisation. Call once only.
*
* @param pool - pool to register any shutdown cleanups, etc
*/
APU_DECLARE(apr_status_t) apr_dbd_init(apr_pool_t *pool);
/** apr_dbd_get_driver: get the driver struct for a name
*
* @param pool - (process) pool to register cleanup
* @param name - driver name
* @param driver - pointer to driver struct.
* @return APR_SUCCESS for success
* @return APR_ENOTIMPL for no driver (when DSO not enabled)
* @return APR_EDSOOPEN if DSO driver file can't be opened
* @return APR_ESYMNOTFOUND if the driver file doesn't contain a driver
*/
APU_DECLARE(apr_status_t) apr_dbd_get_driver(apr_pool_t *pool, const char *name,
const apr_dbd_driver_t **driver);
/** apr_dbd_open_ex: open a connection to a backend
*
* @param pool - working pool
* @param params - arguments to driver (implementation-dependent)
* @param handle - pointer to handle to return
* @param driver - driver struct.
* @param error - descriptive error.
* @return APR_SUCCESS for success
* @return APR_EGENERAL if driver exists but connection failed
* @remarks PostgreSQL: the params is passed directly to the PQconnectdb()
* function (check PostgreSQL documentation for more details on the syntax).
* @remarks SQLite2: the params is split on a colon, with the first part used
* as the filename and second part converted to an integer and used as file
* mode.
* @remarks SQLite3: the params is passed directly to the sqlite3_open()
* function as a filename to be opened (check SQLite3 documentation for more
* details).
* @remarks Oracle: the params can have "user", "pass", "dbname" and "server"
* keys, each followed by an equal sign and a value. Such key/value pairs can
* be delimited by space, CR, LF, tab, semicolon, vertical bar or comma.
* @remarks MySQL: the params can have "host", "port", "user", "pass",
* "dbname", "sock", "flags" "fldsz", "group" and "reconnect" keys, each
* followed by an equal sign and a value. Such key/value pairs can be
* delimited by space, CR, LF, tab, semicolon, vertical bar or comma. For
* now, "flags" can only recognise CLIENT_FOUND_ROWS (check MySQL manual for
* details). The value associated with "fldsz" determines maximum amount of
* memory (in bytes) for each of the fields in the result set of prepared
* statements. By default, this value is 1 MB. The value associated with
* "group" determines which group from configuration file to use (see
* MYSQL_READ_DEFAULT_GROUP option of mysql_options() in MySQL manual).
* Reconnect is set to 1 by default (i.e. true).
* @remarks FreeTDS: the params can have "username", "password", "appname",
* "dbname", "host", "charset", "lang" and "server" keys, each followed by an
* equal sign and a value.
*/
APU_DECLARE(apr_status_t) apr_dbd_open_ex(const apr_dbd_driver_t *driver,
apr_pool_t *pool, const char *params,
apr_dbd_t **handle,
const char **error);
/** apr_dbd_open: open a connection to a backend
*
* @param pool - working pool
* @param params - arguments to driver (implementation-dependent)
* @param handle - pointer to handle to return
* @param driver - driver struct.
* @return APR_SUCCESS for success
* @return APR_EGENERAL if driver exists but connection failed
* @see apr_dbd_open_ex
*/
APU_DECLARE(apr_status_t) apr_dbd_open(const apr_dbd_driver_t *driver,
apr_pool_t *pool, const char *params,
apr_dbd_t **handle);
/** apr_dbd_close: close a connection to a backend
*
* @param handle - handle to close
* @param driver - driver struct.
* @return APR_SUCCESS for success or error status
*/
APU_DECLARE(apr_status_t) apr_dbd_close(const apr_dbd_driver_t *driver,
apr_dbd_t *handle);
/* apr-function-shaped versions of things */
/** apr_dbd_name: get the name of the driver
*
* @param driver - the driver
* @return - name
*/
APU_DECLARE(const char*) apr_dbd_name(const apr_dbd_driver_t *driver);
/** apr_dbd_native_handle: get native database handle of the underlying db
*
* @param driver - the driver
* @param handle - apr_dbd handle
* @return - native handle
*/
APU_DECLARE(void*) apr_dbd_native_handle(const apr_dbd_driver_t *driver,
apr_dbd_t *handle);
/** check_conn: check status of a database connection
*
* @param driver - the driver
* @param pool - working pool
* @param handle - the connection to check
* @return APR_SUCCESS or error
*/
APU_DECLARE(int) apr_dbd_check_conn(const apr_dbd_driver_t *driver, apr_pool_t *pool,
apr_dbd_t *handle);
/** apr_dbd_set_dbname: select database name. May be a no-op if not supported.
*
* @param driver - the driver
* @param pool - working pool
* @param handle - the connection
* @param name - the database to select
* @return 0 for success or error code
*/
APU_DECLARE(int) apr_dbd_set_dbname(const apr_dbd_driver_t *driver, apr_pool_t *pool,
apr_dbd_t *handle, const char *name);
/** apr_dbd_transaction_start: start a transaction. May be a no-op.
*
* @param driver - the driver
* @param pool - a pool to use for error messages (if any).
* @param handle - the db connection
* @param trans - ptr to a transaction. May be null on entry
* @return 0 for success or error code
* @remarks Note that transaction modes, set by calling
* apr_dbd_transaction_mode_set(), will affect all query/select calls within
* a transaction. By default, any error in query/select during a transaction
* will cause the transaction to inherit the error code and any further
* query/select calls will fail immediately. Put transaction in "ignore
* errors" mode to avoid that. Use "rollback" mode to do explicit rollback.
*/
APU_DECLARE(int) apr_dbd_transaction_start(const apr_dbd_driver_t *driver,
apr_pool_t *pool,
apr_dbd_t *handle,
apr_dbd_transaction_t **trans);
/** apr_dbd_transaction_end: end a transaction
* (commit on success, rollback on error).
* May be a no-op.
*
* @param driver - the driver
* @param handle - the db connection
* @param trans - the transaction.
* @return 0 for success or error code
*/
APU_DECLARE(int) apr_dbd_transaction_end(const apr_dbd_driver_t *driver,
apr_pool_t *pool,
apr_dbd_transaction_t *trans);
#define APR_DBD_TRANSACTION_COMMIT 0x00 /**< commit the transaction */
#define APR_DBD_TRANSACTION_ROLLBACK 0x01 /**< rollback the transaction */
#define APR_DBD_TRANSACTION_IGNORE_ERRORS 0x02 /**< ignore transaction errors */
/** apr_dbd_transaction_mode_get: get the mode of transaction
*
* @param driver - the driver
* @param trans - the transaction
* @return mode of transaction
*/
APU_DECLARE(int) apr_dbd_transaction_mode_get(const apr_dbd_driver_t *driver,
apr_dbd_transaction_t *trans);
/** apr_dbd_transaction_mode_set: set the mode of transaction
*
* @param driver - the driver
* @param trans - the transaction
* @param mode - new mode of the transaction
* @return the mode of transaction in force after the call
*/
APU_DECLARE(int) apr_dbd_transaction_mode_set(const apr_dbd_driver_t *driver,
apr_dbd_transaction_t *trans,
int mode);
/** apr_dbd_query: execute an SQL query that doesn't return a result set
*
* @param driver - the driver
* @param handle - the connection
* @param nrows - number of rows affected.
* @param statement - the SQL statement to execute
* @return 0 for success or error code
*/
APU_DECLARE(int) apr_dbd_query(const apr_dbd_driver_t *driver, apr_dbd_t *handle,
int *nrows, const char *statement);
/** apr_dbd_select: execute an SQL query that returns a result set
*
* @param driver - the driver
* @param pool - pool to allocate the result set
* @param handle - the connection
* @param res - pointer to result set pointer. May point to NULL on entry
* @param statement - the SQL statement to execute
* @param random - 1 to support random access to results (seek any row);
* 0 to support only looping through results in order
* (async access - faster)
* @return 0 for success or error code
*/
APU_DECLARE(int) apr_dbd_select(const apr_dbd_driver_t *driver, apr_pool_t *pool,
apr_dbd_t *handle, apr_dbd_results_t **res,
const char *statement, int random);
/** apr_dbd_num_cols: get the number of columns in a results set
*
* @param driver - the driver
* @param res - result set.
* @return number of columns
*/
APU_DECLARE(int) apr_dbd_num_cols(const apr_dbd_driver_t *driver,
apr_dbd_results_t *res);
/** apr_dbd_num_tuples: get the number of rows in a results set
* of a synchronous select
*
* @param driver - the driver
* @param res - result set.
* @return number of rows, or -1 if the results are asynchronous
*/
APU_DECLARE(int) apr_dbd_num_tuples(const apr_dbd_driver_t *driver,
apr_dbd_results_t *res);
/** apr_dbd_get_row: get a row from a result set
*
* @param driver - the driver
* @param pool - pool to allocate the row
* @param res - result set pointer
* @param row - pointer to row pointer. May point to NULL on entry
* @param rownum - row number (counting from 1), or -1 for "next row".
* Ignored if random access is not supported.
* @return 0 for success, -1 for rownum out of range or data finished
*/
APU_DECLARE(int) apr_dbd_get_row(const apr_dbd_driver_t *driver, apr_pool_t *pool,
apr_dbd_results_t *res, apr_dbd_row_t **row,
int rownum);
/** apr_dbd_get_entry: get an entry from a row
*
* @param driver - the driver
* @param row - row pointer
* @param col - entry number
* @return value from the row, or NULL if col is out of bounds.
*/
APU_DECLARE(const char*) apr_dbd_get_entry(const apr_dbd_driver_t *driver,
apr_dbd_row_t *row, int col);
/** apr_dbd_get_name: get an entry name from a result set
*
* @param driver - the driver
* @param res - result set pointer
* @param col - entry number
* @return name of the entry, or NULL if col is out of bounds.
*/
APU_DECLARE(const char*) apr_dbd_get_name(const apr_dbd_driver_t *driver,
apr_dbd_results_t *res, int col);
/** apr_dbd_error: get current error message (if any)
*
* @param driver - the driver
* @param handle - the connection
* @param errnum - error code from operation that returned an error
* @return the database current error message, or message for errnum
* (implementation-dependent whether errnum is ignored)
*/
APU_DECLARE(const char*) apr_dbd_error(const apr_dbd_driver_t *driver,
apr_dbd_t *handle, int errnum);
/** apr_dbd_escape: escape a string so it is safe for use in query/select
*
* @param driver - the driver
* @param pool - pool to alloc the result from
* @param string - the string to escape
* @param handle - the connection
* @return the escaped, safe string
*/
APU_DECLARE(const char*) apr_dbd_escape(const apr_dbd_driver_t *driver,
apr_pool_t *pool, const char *string,
apr_dbd_t *handle);
/** apr_dbd_prepare: prepare a statement
*
* @param driver - the driver
* @param pool - pool to alloc the result from
* @param handle - the connection
* @param query - the SQL query
* @param label - A label for the prepared statement.
* use NULL for temporary prepared statements
* (eg within a Request in httpd)
* @param statement - statement to prepare. May point to null on entry.
* @return 0 for success or error code
* @remarks To specify parameters of the prepared query, use \%s, \%d etc.
* (see below for full list) in place of database specific parameter syntax
* (e.g. for PostgreSQL, this would be $1, $2, for SQLite3 this would be ?
* etc.). For instance: "SELECT name FROM customers WHERE name=%s" would be
* a query that this function understands.
* @remarks Here is the full list of format specifiers that this function
* understands and what they map to in SQL: \%hhd (TINY INT), \%hhu (UNSIGNED
* TINY INT), \%hd (SHORT), \%hu (UNSIGNED SHORT), \%d (INT), \%u (UNSIGNED
* INT), \%ld (LONG), \%lu (UNSIGNED LONG), \%lld (LONG LONG), \%llu
* (UNSIGNED LONG LONG), \%f (FLOAT, REAL), \%lf (DOUBLE PRECISION), \%s
* (VARCHAR), \%pDt (TEXT), \%pDi (TIME), \%pDd (DATE), \%pDa (DATETIME),
* \%pDs (TIMESTAMP), \%pDz (TIMESTAMP WITH TIME ZONE), \%pDb (BLOB), \%pDc
* (CLOB) and \%pDn (NULL). Not all databases have support for all these
* types, so the underlying driver will attempt the "best match" where
* possible. A \% followed by any letter not in the above list will be
* interpreted as VARCHAR (i.e. \%s).
*/
APU_DECLARE(int) apr_dbd_prepare(const apr_dbd_driver_t *driver, apr_pool_t *pool,
apr_dbd_t *handle, const char *query,
const char *label,
apr_dbd_prepared_t **statement);
/** apr_dbd_pquery: query using a prepared statement + args
*
* @param driver - the driver
* @param pool - working pool
* @param handle - the connection
* @param nrows - number of rows affected.
* @param statement - the prepared statement to execute
* @param nargs - ignored (for backward compatibility only)
* @param args - args to prepared statement
* @return 0 for success or error code
*/
APU_DECLARE(int) apr_dbd_pquery(const apr_dbd_driver_t *driver, apr_pool_t *pool,
apr_dbd_t *handle, int *nrows,
apr_dbd_prepared_t *statement, int nargs,
const char **args);
/** apr_dbd_pselect: select using a prepared statement + args
*
* @param driver - the driver
* @param pool - working pool
* @param handle - the connection
* @param res - pointer to query results. May point to NULL on entry
* @param statement - the prepared statement to execute
* @param random - Whether to support random-access to results
* @param nargs - ignored (for backward compatibility only)
* @param args - args to prepared statement
* @return 0 for success or error code
*/
APU_DECLARE(int) apr_dbd_pselect(const apr_dbd_driver_t *driver, apr_pool_t *pool,
apr_dbd_t *handle, apr_dbd_results_t **res,
apr_dbd_prepared_t *statement, int random,
int nargs, const char **args);
/** apr_dbd_pvquery: query using a prepared statement + args
*
* @param driver - the driver
* @param pool - working pool
* @param handle - the connection
* @param nrows - number of rows affected.
* @param statement - the prepared statement to execute
* @param ... - varargs list
* @return 0 for success or error code
*/
APU_DECLARE_NONSTD(int) apr_dbd_pvquery(const apr_dbd_driver_t *driver,
apr_pool_t *pool,
apr_dbd_t *handle, int *nrows,
apr_dbd_prepared_t *statement, ...);
/** apr_dbd_pvselect: select using a prepared statement + args
*
* @param driver - the driver
* @param pool - working pool
* @param handle - the connection
* @param res - pointer to query results. May point to NULL on entry
* @param statement - the prepared statement to execute
* @param random - Whether to support random-access to results
* @param ... - varargs list
* @return 0 for success or error code
*/
APU_DECLARE_NONSTD(int) apr_dbd_pvselect(const apr_dbd_driver_t *driver,
apr_pool_t *pool, apr_dbd_t *handle,
apr_dbd_results_t **res,
apr_dbd_prepared_t *statement,
int random, ...);
/** apr_dbd_pbquery: query using a prepared statement + binary args
*
* @param driver - the driver
* @param pool - working pool
* @param handle - the connection
* @param nrows - number of rows affected.
* @param statement - the prepared statement to execute
* @param args - binary args to prepared statement
* @return 0 for success or error code
*/
APU_DECLARE(int) apr_dbd_pbquery(const apr_dbd_driver_t *driver,
apr_pool_t *pool, apr_dbd_t *handle,
int *nrows, apr_dbd_prepared_t *statement,
const void **args);
/** apr_dbd_pbselect: select using a prepared statement + binary args
*
* @param driver - the driver
* @param pool - working pool
* @param handle - the connection
* @param res - pointer to query results. May point to NULL on entry
* @param statement - the prepared statement to execute
* @param random - Whether to support random-access to results
* @param args - binary args to prepared statement
* @return 0 for success or error code
*/
APU_DECLARE(int) apr_dbd_pbselect(const apr_dbd_driver_t *driver,
apr_pool_t *pool,
apr_dbd_t *handle, apr_dbd_results_t **res,
apr_dbd_prepared_t *statement, int random,
const void **args);
/** apr_dbd_pvbquery: query using a prepared statement + binary args
*
* @param driver - the driver
* @param pool - working pool
* @param handle - the connection
* @param nrows - number of rows affected.
* @param statement - the prepared statement to execute
* @param ... - varargs list of binary args
* @return 0 for success or error code
*/
APU_DECLARE_NONSTD(int) apr_dbd_pvbquery(const apr_dbd_driver_t *driver,
apr_pool_t *pool,
apr_dbd_t *handle, int *nrows,
apr_dbd_prepared_t *statement, ...);
/** apr_dbd_pvbselect: select using a prepared statement + binary args
*
* @param driver - the driver
* @param pool - working pool
* @param handle - the connection
* @param res - pointer to query results. May point to NULL on entry
* @param statement - the prepared statement to execute
* @param random - Whether to support random-access to results
* @param ... - varargs list of binary args
* @return 0 for success or error code
*/
APU_DECLARE_NONSTD(int) apr_dbd_pvbselect(const apr_dbd_driver_t *driver,
apr_pool_t *pool, apr_dbd_t *handle,
apr_dbd_results_t **res,
apr_dbd_prepared_t *statement,
int random, ...);
/** apr_dbd_datum_get: get a binary entry from a row
*
* @param driver - the driver
* @param row - row pointer
* @param col - entry number
* @param type - type of data to get
* @param data - pointer to data, allocated by the caller
* @return APR_SUCCESS on success, APR_ENOENT if data is NULL or APR_EGENERAL
*/
APU_DECLARE(apr_status_t) apr_dbd_datum_get(const apr_dbd_driver_t *driver,
apr_dbd_row_t *row, int col,
apr_dbd_type_e type, void *data);
/** @} */
#ifdef __cplusplus
}
#endif
#endif
|