libpq-fe.h

跨平台C++基础库

extern const char *PQparameterStatus(const PGconn *conn,
				  const char *paramName);
extern int	PQprotocolVersion(const PGconn *conn);
extern int	PQserverVersion(const PGconn *conn);
extern char *PQerrorMessage(const PGconn *conn);
extern int	PQsocket(const PGconn *conn);
extern int	PQbackendPID(const PGconn *conn);
extern int	PQclientEncoding(const PGconn *conn);
extern int	PQsetClientEncoding(PGconn *conn, const char *encoding);

/* Get the OpenSSL structure associated with a connection. Returns NULL for
 * unencrypted connections or if any other TLS library is in use. */
extern void *PQgetssl(PGconn *conn);

/* Tell libpq whether it needs to initialize OpenSSL */
extern void PQinitSSL(int do_init);

/* Set verbosity for PQerrorMessage and PQresultErrorMessage */
extern PGVerbosity PQsetErrorVerbosity(PGconn *conn, PGVerbosity verbosity);

/* Enable/disable tracing */
extern void PQtrace(PGconn *conn, FILE *debug_port);
extern void PQuntrace(PGconn *conn);

/* Override default notice handling routines */
extern PQnoticeReceiver PQsetNoticeReceiver(PGconn *conn,
					PQnoticeReceiver proc,
					void *arg);
extern PQnoticeProcessor PQsetNoticeProcessor(PGconn *conn,
					 PQnoticeProcessor proc,
					 void *arg);

/*
 *	   Used to set callback that prevents concurrent access to
 *	   non-thread safe functions that libpq needs.
 *	   The default implementation uses a libpq internal mutex.
 *	   Only required for multithreaded apps that use kerberos
 *	   both within their app and for postgresql connections.
 */
typedef void (*pgthreadlock_t) (int acquire);

extern pgthreadlock_t PQregisterThreadLock(pgthreadlock_t newhandler);

/* === in fe-exec.c === */

/* Simple synchronous query */
extern PGresult *PQexec(PGconn *conn, const char *query);
extern PGresult *PQexecParams(PGconn *conn,
			 const char *command,
			 int nParams,
			 const Oid *paramTypes,
			 const char *const * paramValues,
			 const int *paramLengths,
			 const int *paramFormats,
			 int resultFormat);
extern PGresult *PQprepare(PGconn *conn, const char *stmtName,
		  const char *query, int nParams,
		  const Oid *paramTypes);
extern PGresult *PQexecPrepared(PGconn *conn,
			   const char *stmtName,
			   int nParams,
			   const char *const * paramValues,
			   const int *paramLengths,
			   const int *paramFormats,
			   int resultFormat);

/* Interface for multiple-result or asynchronous queries */
extern int	PQsendQuery(PGconn *conn, const char *query);
extern int PQsendQueryParams(PGconn *conn,
				  const char *command,
				  int nParams,
				  const Oid *paramTypes,
				  const char *const * paramValues,
				  const int *paramLengths,
				  const int *paramFormats,
				  int resultFormat);
extern int PQsendPrepare(PGconn *conn, const char *stmtName,
			  const char *query, int nParams,
			  const Oid *paramTypes);
extern int PQsendQueryPrepared(PGconn *conn,
					const char *stmtName,
					int nParams,
					const char *const * paramValues,
					const int *paramLengths,
					const int *paramFormats,
					int resultFormat);
extern PGresult *PQgetResult(PGconn *conn);

/* Routines for managing an asynchronous query */
extern int	PQisBusy(PGconn *conn);
extern int	PQconsumeInput(PGconn *conn);

/* LISTEN/NOTIFY support */
extern PGnotify *PQnotifies(PGconn *conn);

/* Routines for copy in/out */
extern int	PQputCopyData(PGconn *conn, const char *buffer, int nbytes);
extern int	PQputCopyEnd(PGconn *conn, const char *errormsg);
extern int	PQgetCopyData(PGconn *conn, char **buffer, int async);

/* Deprecated routines for copy in/out */
extern int	PQgetline(PGconn *conn, char *string, int length);
extern int	PQputline(PGconn *conn, const char *string);
extern int	PQgetlineAsync(PGconn *conn, char *buffer, int bufsize);
extern int	PQputnbytes(PGconn *conn, const char *buffer, int nbytes);
extern int	PQendcopy(PGconn *conn);

/* Set blocking/nonblocking connection to the backend */
extern int	PQsetnonblocking(PGconn *conn, int arg);
extern int	PQisnonblocking(const PGconn *conn);
extern int	PQisthreadsafe(void);

/* Force the write buffer to be written (or at least try) */
extern int	PQflush(PGconn *conn);

/*
 * "Fast path" interface --- not really recommended for application
 * use
 */
extern PGresult *PQfn(PGconn *conn,
	 int fnid,
	 int *result_buf,
	 int *result_len,
	 int result_is_int,
	 const PQArgBlock *args,
	 int nargs);

/* Accessor functions for PGresult objects */
extern ExecStatusType PQresultStatus(const PGresult *res);
extern char *PQresStatus(ExecStatusType status);
extern char *PQresultErrorMessage(const PGresult *res);
extern char *PQresultErrorField(const PGresult *res, int fieldcode);
extern int	PQntuples(const PGresult *res);
extern int	PQnfields(const PGresult *res);
extern int	PQbinaryTuples(const PGresult *res);
extern char *PQfname(const PGresult *res, int field_num);
extern int	PQfnumber(const PGresult *res, const char *field_name);
extern Oid	PQftable(const PGresult *res, int field_num);
extern int	PQftablecol(const PGresult *res, int field_num);
extern int	PQfformat(const PGresult *res, int field_num);
extern Oid	PQftype(const PGresult *res, int field_num);
extern int	PQfsize(const PGresult *res, int field_num);
extern int	PQfmod(const PGresult *res, int field_num);
extern char *PQcmdStatus(PGresult *res);
extern char *PQoidStatus(const PGresult *res);	/* old and ugly */
extern Oid	PQoidValue(const PGresult *res);	/* new and improved */
extern char *PQcmdTuples(PGresult *res);
extern char *PQgetvalue(const PGresult *res, int tup_num, int field_num);
extern int	PQgetlength(const PGresult *res, int tup_num, int field_num);
extern int	PQgetisnull(const PGresult *res, int tup_num, int field_num);
extern int	PQnparams(const PGresult *res);
extern Oid	PQparamtype(const PGresult *res, int param_num);

/* Describe prepared statements and portals */
extern PGresult *PQdescribePrepared(PGconn *conn, const char *stmt);
extern PGresult *PQdescribePortal(PGconn *conn, const char *portal);
extern int	PQsendDescribePrepared(PGconn *conn, const char *stmt);
extern int	PQsendDescribePortal(PGconn *conn, const char *portal);

/* Delete a PGresult */
extern void PQclear(PGresult *res);

/* For freeing other alloc'd results, such as PGnotify structs */
extern void PQfreemem(void *ptr);

/* Exists for backward compatibility.  bjm 2003-03-24 */
#define PQfreeNotify(ptr) PQfreemem(ptr)

/* Define the string so all uses are consistent. */
#define PQnoPasswordSupplied	"fe_sendauth: no password supplied\n"

/*
 * Make an empty PGresult with given status (some apps find this
 * useful). If conn is not NULL and status indicates an error, the
 * conn's errorMessage is copied.
 */
extern PGresult *PQmakeEmptyPGresult(PGconn *conn, ExecStatusType status);


/* Quoting strings before inclusion in queries. */
extern size_t PQescapeStringConn(PGconn *conn,
				   char *to, const char *from, size_t length,
				   int *error);
extern unsigned char *PQescapeByteaConn(PGconn *conn,
				  const unsigned char *from, size_t from_length,
				  size_t *to_length);
extern unsigned char *PQunescapeBytea(const unsigned char *strtext,
				size_t *retbuflen);

/* These forms are deprecated! */
extern size_t PQescapeString(char *to, const char *from, size_t length);
extern unsigned char *PQescapeBytea(const unsigned char *from, size_t from_length,
			  size_t *to_length);



/* === in fe-print.c === */

extern void
PQprint(FILE *fout,				/* output stream */
		const PGresult *res,
		const PQprintOpt *ps);	/* option structure */

/*
 * really old printing routines
 */
extern void
PQdisplayTuples(const PGresult *res,
				FILE *fp,		/* where to send the output */
				int fillAlign,	/* pad the fields with spaces */
				const char *fieldSep,	/* field separator */
				int printHeader,	/* display headers? */
				int quiet);

extern void
PQprintTuples(const PGresult *res,
			  FILE *fout,		/* output stream */
			  int printAttName, /* print attribute names */
			  int terseOutput,	/* delimiter bars */
			  int width);		/* width of column, if 0, use variable width */


/* === in fe-lobj.c === */

/* Large-object access routines */
extern int	lo_open(PGconn *conn, Oid lobjId, int mode);
extern int	lo_close(PGconn *conn, int fd);
extern int	lo_read(PGconn *conn, int fd, char *buf, size_t len);
extern int	lo_write(PGconn *conn, int fd, const char *buf, size_t len);
extern int	lo_lseek(PGconn *conn, int fd, int offset, int whence);
extern Oid	lo_creat(PGconn *conn, int mode);
extern Oid	lo_create(PGconn *conn, Oid lobjId);
extern int	lo_tell(PGconn *conn, int fd);
extern int	lo_unlink(PGconn *conn, Oid lobjId);
extern Oid	lo_import(PGconn *conn, const char *filename);
extern int	lo_export(PGconn *conn, Oid lobjId, const char *filename);

/* === in fe-misc.c === */

/* Determine length of multibyte encoded char at *s */
extern int	PQmblen(const char *s, int encoding);

/* Determine display length of multibyte encoded char at *s */
extern int	PQdsplen(const char *s, int encoding);

/* Get encoding id from environment variable PGCLIENTENCODING */
extern int	PQenv2encoding(void);

/* === in fe-auth.c === */

extern char *PQencryptPassword(const char *passwd, const char *user);

#ifdef __cplusplus
}
#endif

#endif   /* LIBPQ_FE_H */