/*------------------------------------------------------------------------- * * libpq-fe.h * This file contains definitions for structures and * externs for functions used by frontend postgres applications. * * Portions Copyright (c) 1996-2002, PostgreSQL Global Development Group * Portions Copyright (c) 1994, Regents of the University of California * * $Id: libpq-fe.h,v 1.86 2002/09/04 20:31:47 momjian Exp $ * *------------------------------------------------------------------------- */ #ifndef LIBPQ_FE_H #define LIBPQ_FE_H #ifdef __cplusplus extern "C" { #endif #include /* * postgres_ext.h defines the backend's externally visible types, * such as Oid. */ #include "postgres_ext.h" /* SSL type is needed here only to declare PQgetssl() */ #ifdef USE_SSL #include #endif /* Application-visible enum types */ typedef enum { /* * Although you may decide to change this list in some way, values * which become unused should never be removed, nor should constants * be redefined - that would break compatibility with existing code. */ CONNECTION_OK, CONNECTION_BAD, /* Non-blocking mode only below here */ /* * The existence of these should never be relied upon - they should * only be used for user feedback or similar purposes. */ CONNECTION_STARTED, /* Waiting for connection to be made. */ CONNECTION_MADE, /* Connection OK; waiting to send. */ CONNECTION_AWAITING_RESPONSE, /* Waiting for a response from the * postmaster. */ CONNECTION_AUTH_OK, /* Received authentication; waiting for * backend startup. */ CONNECTION_SETENV /* Negotiating environment. */ } ConnStatusType; typedef enum { PGRES_POLLING_FAILED = 0, PGRES_POLLING_READING, /* These two indicate that one may */ PGRES_POLLING_WRITING, /* use select before polling again. */ PGRES_POLLING_OK, PGRES_POLLING_ACTIVE /* Can call poll function immediately. */ } PostgresPollingStatusType; typedef enum { PGRES_EMPTY_QUERY = 0, PGRES_COMMAND_OK, /* a query command that doesn't return * anything was executed properly by the * backend */ PGRES_TUPLES_OK, /* a query command that returns tuples was * executed properly by the backend, * PGresult contains the result tuples */ PGRES_COPY_OUT, /* Copy Out data transfer in progress */ PGRES_COPY_IN, /* Copy In data transfer in progress */ PGRES_BAD_RESPONSE, /* an unexpected response was recv'd from * the backend */ PGRES_NONFATAL_ERROR, PGRES_FATAL_ERROR } ExecStatusType; /* PGconn encapsulates a connection to the backend. * The contents of this struct are not supposed to be known to applications. */ typedef struct pg_conn PGconn; /* PGresult encapsulates the result of a query (or more precisely, of a single * SQL command --- a query string given to PQsendQuery can contain multiple * commands and thus return multiple PGresult objects). * The contents of this struct are not supposed to be known to applications. */ typedef struct pg_result PGresult; /* PGnotify represents the occurrence of a NOTIFY message. * Ideally this would be an opaque typedef, but it's so simple that it's * unlikely to change. * NOTE: in Postgres 6.4 and later, the be_pid is the notifying backend's, * whereas in earlier versions it was always your own backend's PID. */ typedef struct pgNotify { char *relname; /* name of relation containing data */ int be_pid; /* process id of backend */ } PGnotify; /* PQnoticeProcessor is the function type for the notice-message callback. */ typedef void (*PQnoticeProcessor) (void *arg, const char *message); /* Print options for PQprint() */ typedef char pqbool; typedef struct _PQprintOpt { pqbool header; /* print output field headings and row * count */ pqbool align; /* fill align the fields */ pqbool standard; /* old brain dead format */ pqbool html3; /* output html tables */ pqbool expanded; /* expand tables */ pqbool pager; /* use pager for output if needed */ char *fieldSep; /* field separator */ char *tableOpt; /* insert to HTML */ char *caption; /* HTML
*/ char **fieldName; /* null terminated array of repalcement * field names */ } PQprintOpt; /* ---------------- * Structure for the conninfo parameter definitions returned by PQconndefaults * * All fields except "val" point at static strings which must not be altered. * "val" is either NULL or a malloc'd current-value string. PQconninfoFree() * will release both the val strings and the PQconninfoOption array itself. * ---------------- */ typedef struct _PQconninfoOption { char *keyword; /* The keyword of the option */ char *envvar; /* Fallback environment variable name */ char *compiled; /* Fallback compiled in default value */ char *val; /* Option's current value, or NULL */ char *label; /* Label for field in connect dialog */ char *dispchar; /* Character to display for this field in * a connect dialog. Values are: "" * Display entered value as is "*" * Password field - hide value "D" Debug * option - don't show by default */ int dispsize; /* Field size in characters for dialog */ } PQconninfoOption; /* ---------------- * PQArgBlock -- structure for PQfn() arguments * ---------------- */ typedef struct { int len; int isint; union { int *ptr; /* can't use void (dec compiler barfs) */ int integer; } u; } PQArgBlock; /* ---------------- * Exported functions of libpq * ---------------- */ /* === in fe-connect.c === */ /* make a new client connection to the backend */ /* Asynchronous (non-blocking) */ extern PGconn *PQconnectStart(const char *conninfo); extern PostgresPollingStatusType PQconnectPoll(PGconn *conn); /* Synchronous (blocking) */ extern PGconn *PQconnectdb(const char *conninfo); extern PGconn *PQsetdbLogin(const char *pghost, const char *pgport, const char *pgoptions, const char *pgtty, const char *dbName, const char *login, const char *pwd); #define PQsetdb(M_PGHOST,M_PGPORT,M_PGOPT,M_PGTTY,M_DBNAME) \ PQsetdbLogin(M_PGHOST, M_PGPORT, M_PGOPT, M_PGTTY, M_DBNAME, NULL, NULL) /* close the current connection and free the PGconn data structure */ extern void PQfinish(PGconn *conn); /* get info about connection options known to PQconnectdb */ extern PQconninfoOption *PQconndefaults(void); /* free the data structure returned by PQconndefaults() */ extern void PQconninfoFree(PQconninfoOption *connOptions); /* * close the current connection and restablish a new one with the same * parameters */ /* Asynchronous (non-blocking) */ extern int PQresetStart(PGconn *conn); extern PostgresPollingStatusType PQresetPoll(PGconn *conn); /* Synchronous (blocking) */ extern void PQreset(PGconn *conn); /* issue a cancel request */ extern int PQrequestCancel(PGconn *conn); /* Accessor functions for PGconn objects */ extern char *PQdb(const PGconn *conn); extern char *PQuser(const PGconn *conn); extern char *PQpass(const PGconn *conn); extern char *PQhost(const PGconn *conn); extern char *PQport(const PGconn *conn); extern char *PQtty(const PGconn *conn); extern char *PQoptions(const PGconn *conn); extern ConnStatusType PQstatus(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); #ifdef USE_SSL /* Get the SSL structure associated with a connection */ extern SSL *PQgetssl(PGconn *conn); #endif /* Enable/disable tracing */ extern void PQtrace(PGconn *conn, FILE *debug_port); extern void PQuntrace(PGconn *conn); /* Override default notice processor */ extern PQnoticeProcessor PQsetNoticeProcessor(PGconn *conn, PQnoticeProcessor proc, void *arg); /* === in fe-exec.c === */ /* Quoting strings before inclusion in queries. */ extern size_t PQescapeString(char *to, const char *from, size_t length); extern unsigned char *PQescapeBytea(unsigned char *bintext, size_t binlen, size_t *bytealen); extern unsigned char *PQunescapeBytea(unsigned char *strtext, size_t *retbuflen); /* Simple synchronous query */ extern PGresult *PQexec(PGconn *conn, const char *query); extern PGnotify *PQnotifies(PGconn *conn); extern void PQfreeNotify(PGnotify *notify); /* Interface for multiple-result or asynchronous queries */ extern int PQsendQuery(PGconn *conn, const char *query); extern PGresult *PQgetResult(PGconn *conn); /* Routines for managing an asychronous query */ extern int PQisBusy(PGconn *conn); extern int PQconsumeInput(PGconn *conn); /* 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); /* Force the write buffer to be written (or at least try) */ extern int PQflush(PGconn *conn); extern int PQsendSome(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 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 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); /* Delete a PGresult */ extern void PQclear(PGresult *res); /* * 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); /* === 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, 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 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 unsigned char *s, int encoding); /* Get encoding id from environment variable PGCLIENTENCODING */ extern int PQenv2encoding(void); #ifdef __cplusplus } #endif #endif /* LIBPQ_FE_H */