libpq-fe.h

/*-------------------------------------------------------------------------
 *
 * libpq-fe.h--
 *    This file contains definitions for structures and
 *    externs for functions used by frontend postgres applications.
 *
 * Copyright (c) 1994, Regents of the University of California
 *
 * $Id: libpq-fe.h,v 1.9 1996/11/04 04:00:56 momjian Exp $
 *
 *-------------------------------------------------------------------------
 */

#ifndef LIBPQ_FE_H
#define LIBPQ_FE_H

#ifdef __cplusplus
extern "C" {
#endif

/* ----------------
 *	include stuff common to fe and be
 * ----------------
 */
/* #include "libpq/libpq.h" */
#include "libpq/pqcomm.h"
#include "lib/dllist.h"

typedef enum {CONNECTION_OK,
	      CONNECTION_BAD}  ConnStatusType;

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 resulttuples */
  PGRES_COPY_OUT, 
  PGRES_COPY_IN,
  PGRES_BAD_RESPONSE, /* an unexpected response was recv'd from the backend */
  PGRES_NONFATAL_ERROR,
  PGRES_FATAL_ERROR

} ExecStatusType;

/* string descriptions of the ExecStatusTypes */
extern const char* pgresStatus[]; 

/* 
 * POSTGRES backend dependent Constants. 
 */

/* ERROR_MSG_LENGTH should really be the same as ELOG_MAXLEN in utils/elog.h*/
#define ERROR_MSG_LENGTH 4096
#define COMMAND_LENGTH 20
#define REMARK_LENGTH 80
#define PORTAL_NAME_LENGTH 16

/* ----------------
 * PQArgBlock --
 *	Information (pointer to array of this structure) required
 *	for the PQfn() call.
 * ----------------
 */
typedef struct {
    int len;
    int isint;
    union {
        int *ptr;	/* can't use void (dec compiler barfs)	*/
	int integer;
    } u;
} PQArgBlock;

typedef struct pgresAttDesc {
  char* name; /* type name */
  Oid adtid;  /* type id */
  int2 adtsize; /* type size */
} PGresAttDesc;

/* use char* for Attribute values,
   ASCII tuples are guaranteed to be null-terminated
   For binary tuples, the first four bytes of the value is the size,
   and the bytes afterwards are the value.  The binary value is 
   not guaranteed to be null-terminated.  In fact, it can have embedded nulls*/

#define NULL_LEN	(-1)	/* pg_result len for NULL value */

typedef struct pgresAttValue {
  int len; /* length in bytes of the value */
  char *value; /* actual value */
} PGresAttValue;

typedef struct pgNotify {
    char relname[NAMEDATALEN];	/* name of relation containing data */
    int be_pid;			/* process id of backend */
} PGnotify;

/* PGconn encapsulates a connection to the backend */
typedef struct pg_conn{
  char *pghost; /* the machine on which the server is running */
  char *pgtty;  /* tty on which the backend messages is displayed */
  char *pgport; /* the communication port with the backend */
  char *pgoptions; /* options to start the backend with */
  char *dbName; /* database name */
  ConnStatusType status;
  char errorMessage[ERROR_MSG_LENGTH];
  /* pipes for be/fe communication */
  FILE *Pfin;
  FILE *Pfout;
  FILE *Pfdebug;
  void *port; /* really a Port* */
  int asyncNotifyWaiting;
  Dllist* notifyList;
  char *pguser;  /* Postgres username of user who is connected */
} PGconn;

#define CMDSTATUS_LEN 40

/* PGresult encapsulates the result of a query */
/* unlike the old libpq, we assume that queries only return in one group */
typedef struct pg_result{
  int ntups;
  int numAttributes;
  PGresAttDesc *attDescs;
  PGresAttValue* *tuples; /* each PGresTuple is an array of PGresAttValue's */
  int tupArrSize;         /* size of tuples array allocated */
  ExecStatusType resultStatus;
  char cmdStatus[CMDSTATUS_LEN]; /* cmd status from the last insert query*/
  int binary; /* binary tuple values if binary == 1, otherwise ASCII */
  PGconn* conn;
} PGresult;

struct _PQprintOpt {
    bool header;         /* print output field headings and row count */
    bool align;          /* fill align the fields */
    bool standard;       /* old brain dead format */
    bool html3;          /* output html tables */
    bool expanded;       /* expand tables */
    bool pager;          /* use pager for output if needed */
    char *fieldSep;      /* field separator */
    char *tableOpt;	 /* insert to HTML <table ...> */
    char *caption;       /* HTML <caption> */
    char **fieldName;    /* null terminated array of repalcement field names */
};

typedef struct _PQprintOpt PQprintOpt;

/* ===  in fe-connect.c === */
  /* make a new client connection to the backend */
extern PGconn* PQsetdb(const char* pghost, const char* pgport, const char* pgoptions, 
		       const char* pgtty, const char* dbName);
  /* close the current connection and free the PGconn data structure */
extern void PQfinish(PGconn* conn);
  /* close the current connection and restablish a new one with the same 
     parameters */
extern void PQreset(PGconn* conn);

extern char* PQdb(PGconn* conn);
extern char* PQhost(PGconn* conn);
extern char* PQoptions(PGconn* conn);
extern char* PQport(PGconn* conn);
extern char* PQtty(PGconn* conn);
extern ConnStatusType PQstatus(PGconn* conn);
extern char* PQerrorMessage(PGconn* conn);
extern void PQtrace(PGconn *conn, FILE* debug_port);
extern void PQuntrace(PGconn *conn);

/* === in fe-exec.c === */
extern PGresult* PQexec(PGconn* conn, const char* query);
extern int PQgetline(PGconn *conn, char* string, int length);
extern int PQendcopy(PGconn *conn);
extern void PQputline(PGconn *conn, const char* string);
extern ExecStatusType PQresultStatus(PGresult* res);
extern int PQntuples(PGresult *res);
extern int PQnfields(PGresult *res);
extern char* PQfname(PGresult *res, int field_num);
extern int PQfnumber(PGresult *res, const char* field_name);
extern Oid PQftype(PGresult *res, int field_num);
extern int2 PQfsize(PGresult *res, int field_num);
extern char* PQcmdStatus(PGresult *res);
extern const char* PQoidStatus(PGresult *res);
extern char* PQgetvalue(PGresult *res, int tup_num, int field_num);
extern int PQgetlength(PGresult *res, int tup_num, int field_num);
extern int PQgetisnull(PGresult *res, int tup_num, int field_num);
extern void PQclear(PGresult* res);
/* PQdisplayTuples() is a better version of PQprintTuples() */
extern void PQdisplayTuples(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(PGresult* res, 
			  FILE* fout,      /* output stream */
			  int printAttName,/* print attribute names or not*/
			  int terseOutput, /* delimiter bars or not?*/
			  int width        /* width of column, 
					      if 0, use variable width */
			  );
extern void PQprint(FILE* fout,      /* output stream */
		    PGresult* res, 
		    PQprintOpt *ps   /* option structure */
		    );
extern PGnotify* PQnotifies(PGconn *conn);
extern PGresult* PQfn(PGconn* conn,
		      int fnid, 
		      int *result_buf, 
		      int *result_len,
		      int result_is_int,
		      PQArgBlock *args, 
		      int nargs);
/* === in fe-auth.c === */
extern MsgType fe_getauthsvc(char* PQerrormsg);
extern void fe_setauthsvc(const char *name, char* PQerrormsg);
extern char *fe_getauthname(char* PQerrormsg);

/* === in fe-misc.c === */
/* pqGets and pqPuts gets and sends strings to the file stream
   returns 0 if successful 
   if debug is non-null, debugging output is sent to that stream 
*/
extern int pqGets(char* s, int maxlen, FILE* stream, FILE* debug);
extern int pqGetnchar(char* s, int maxlen, FILE* stream, FILE* debug);
extern int pqPutnchar(const char* s, int maxlen, FILE* stream, FILE* debug);
extern int pqPuts(const char* s, FILE* stream, FILE* debug );
extern int pqGetc(FILE* stream, FILE *debug);
/* get a n-byte integer from the stream into result */
/* returns 0 if successful */
extern int pqGetInt(int* result, int bytes, FILE* stream, FILE *debug );
/* put a n-byte integer into the stream */
/* returns 0 if successful */
extern int pqPutInt(int n, int bytes, FILE* stream, FILE *debug );
extern void pqFlush(FILE* stream, FILE* debug);

/* === in fe-lobj.c === */
int lo_open(PGconn* conn, Oid lobjId, int mode);
int lo_close(PGconn *conn, int fd);
int lo_read(PGconn *conn, int fd, char *buf, int len);
int lo_write(PGconn *conn, int fd, char *buf, int len);
int lo_lseek(PGconn *conn, int fd, int offset, int whence);
Oid lo_creat(PGconn *conn, int mode);
int lo_tell(PGconn *conn, int fd);
int lo_unlink(PGconn *conn, Oid lobjId);
Oid lo_import(PGconn *conn, char *filename);
int lo_export(PGconn *conn, Oid lobjId, char *filename);
/* max length of message to send  */
#define MAX_MESSAGE_LEN 8193

/* maximum number of fields in a tuple */
#define BYTELEN 8
#define MAX_FIELDS 512

/* fall back options if they are not specified by arguments or defined
   by environment variables */
#define DefaultHost	"localhost"
#define DefaultTty	""
#define DefaultOption	""

typedef void *TUPLE;
#define palloc malloc
#define pfree free

#if defined(sparc)
extern char *sys_errlist[];
#define strerror(A) (sys_errlist[(A)])
#endif /* sparc */

#ifdef __cplusplus
};
#endif

#endif /* LIBPQ_FE_H */