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Editing: apr_dbd.h
/* 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 driver - driver struct. * @param pool - working pool * @param params - arguments to driver (implementation-dependent) * @param handle - pointer to handle to return * @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). */ 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 driver - driver struct. * @param pool - working pool * @param params - arguments to driver (implementation-dependent) * @param handle - pointer to handle to return * @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 driver - driver struct. * @param handle - handle to close * @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
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