+++ /dev/null
-.\" This is -*-nroff-*-
-.\" XXX standard disclaimer belongs here....
-.\" $Header: /cvsroot/pgsql/src/interfaces/libpgeasy/Attic/pgeasy.3,v 1.1 1999/10/11 18:03:00 momjian Exp $
-.TH PGEASY INTRO 08/08/98 PostgreSQL PostgreSQL
-.SH DESCRIPTION
-Pgeasy allows you to cleanly interface to the libpq library,
-more like a 4gl SQL interface.
-.PP
-It consists of set of simplified C functions that encapsulate the
-functionality of libpq.
-The functions are:
-
-.nf
-PGresult *doquery(char *query);
-PGconn *connectdb();
-void disconnectdb();
-
-int fetch(void *param,...);
-int fetchwithnulls(void *param,...);
-void reset_fetch();
-
-void on_error_continue();
-void on_error_stop();
-
-PGresult *get_result();
-void set_result(PGresult *newres);
-void unset_result(PGresult *oldres);
-.fi
-.PP
-Many functions return a structure or value, so you can do more work
-with the result if required.
-.PP
-You basically connect to the database with
-.BR connectdb ,
-issue your query with
-.BR doquery ,
-fetch the results with
-.BR fetch ,
-and finish with
-.BR disconnectdb .
-.PP
-For
-.IR select
-queries,
-.BR fetch
-allows you to pass pointers as parameters, and on return the variables
-are filled with data from the binary cursor you opened. These binary
-cursors can not be used if you are running the
-.BR pgeasy
-client on a system with a different architecture than the database
-server. If you pass a NULL pointer parameter, the column is skipped.
-.BR fetchwithnulls
-allows you to retieve the
-.IR null
-status of the field by passing an
-.IR int*
-after each result pointer, which returns true or false if the field is null.
-You can always use libpq functions on the PGresult pointer returned by
-.BR doquery .
-.BR reset_fetch
-starts the fetch back at the beginning.
-.PP
-.BR get_result ,
-.BR set_result ,
-and
-.BR unset_result
-allow you to handle multiple result sets at the same time.
-.PP
-There are a variety of demonstration programs in the
-.BR pgeasy
-source directory.
+++ /dev/null
-/*
- * pgeasy.c
- *
-*/
-
-#include <stdio.h>
-#include <string.h>
-#include <stdarg.h>
-
-#include <libpq-fe.h>
-#include "halt.h"
-#include "pgeasy.h"
-
-#define NUL '\0'
-
-#ifndef TRUE
-#define TRUE 1
-#endif
-
-#ifndef FALSE
-#define FALSE 0
-#endif
-
-/* GLOBAL VARIABLES */
-static PGconn *conn;
-static PGresult *res = NULL;
-
-#define ON_ERROR_STOP 0
-#define ON_ERROR_CONTINUE 1
-
-static int on_error_state = ON_ERROR_STOP;
-
-static in_result_block = FALSE;
-static was_get_unset_result = FALSE;
-
-/* LOCAL VARIABLES */
-static int tuple;
-
-/*
-**
-** connectdb - returns PGconn structure
-**
-*/
-PGconn *
-connectdb(char *dbName,
- char *pghost,
- char *pgport,
- char *pgoptions,
- char *pgtty)
-{
- /* make a connection to the database */
- conn = PQsetdb(pghost, pgport, pgoptions, pgtty, dbName);
- if (PQstatus(conn) == CONNECTION_BAD)
- halt("Connection to database '%s' failed.\n%s\n", dbName,
- PQerrorMessage(conn));
- return conn;
-}
-
-/*
-**
-** disconnectdb
-**
-*/
-void
-disconnectdb()
-{
- PQfinish(conn);
-}
-
-/*
-**
-** doquery - returns PGresult structure
-**
-*/
-PGresult *
-doquery(char *query)
-{
- if (res != NULL && in_result_block == FALSE && was_get_unset_result == FALSE)
- PQclear(res);
-
- was_get_unset_result = FALSE;
- res = PQexec(conn, query);
-
- if (on_error_state == ON_ERROR_STOP &&
- (res == NULL ||
- PQresultStatus(res) == PGRES_BAD_RESPONSE ||
- PQresultStatus(res) == PGRES_NONFATAL_ERROR ||
- PQresultStatus(res) == PGRES_FATAL_ERROR))
- {
- if (res != NULL)
- fprintf(stderr, "query error: %s\n", PQcmdStatus(res));
- else
- fprintf(stderr, "connection error: %s\n", PQerrorMessage(conn));
- PQfinish(conn);
- halt("failed request: %s\n", query);
- }
- tuple = 0;
- return res;
-}
-
-/*
-**
-** fetch - returns tuple number (starts at 0), or the value END_OF_TUPLES
-** NULL pointers are skipped
-**
-*/
-int
-fetch(void *param,...)
-{
- va_list ap;
- int arg,
- num_fields;
-
- num_fields = PQnfields(res);
-
- if (tuple >= PQntuples(res))
- return END_OF_TUPLES;
-
- va_start(ap, param);
- for (arg = 0; arg < num_fields; arg++)
- {
- if (param != NULL)
- {
- if (PQfsize(res, arg) == -1)
- {
- memcpy(param, PQgetvalue(res, tuple, arg), PQgetlength(res, tuple, arg));
- ((char *) param)[PQgetlength(res, tuple, arg)] = NUL;
- }
- else
- memcpy(param, PQgetvalue(res, tuple, arg), PQfsize(res, arg));
- }
- param = va_arg(ap, char *);
- }
- va_end(ap);
- return tuple++;
-}
-
-/*
-**
-** fetchwithnulls - returns tuple number (starts at 0),
-** or the value END_OF_TUPLES
-** Returns TRUE or FALSE into null indicator variables
-** NULL pointers are skipped
-*/
-int
-fetchwithnulls(void *param,...)
-{
- va_list ap;
- int arg,
- num_fields;
-
- num_fields = PQnfields(res);
-
- if (tuple >= PQntuples(res))
- return END_OF_TUPLES;
-
- va_start(ap, param);
- for (arg = 0; arg < num_fields; arg++)
- {
- if (param != NULL)
- {
- if (PQfsize(res, arg) == -1)
- {
- memcpy(param, PQgetvalue(res, tuple, arg), PQgetlength(res, tuple, arg));
- ((char *) param)[PQgetlength(res, tuple, arg)] = NUL;
- }
- else
- memcpy(param, PQgetvalue(res, tuple, arg), PQfsize(res, arg));
- }
- param = va_arg(ap, char *);
- if (PQgetisnull(res, tuple, arg) != 0)
- *(int *) param = 1;
- else
- *(int *) param = 0;
- param = va_arg(ap, char *);
- }
- va_end(ap);
- return tuple++;
-}
-
-/*
-**
-** on_error_stop
-**
-*/
-void
-on_error_stop()
-{
- on_error_state = ON_ERROR_STOP;
-}
-
-/*
-**
-** on_error_continue
-**
-*/
-void
-on_error_continue()
-{
- on_error_state = ON_ERROR_CONTINUE;
-}
-
-
-/*
-**
-** get_result
-**
-*/
-PGresult *
-get_result()
-{
- char *cmdstatus = PQcmdStatus(res);
-
- was_get_unset_result = TRUE;
-
- /* we have to store the fetch location somewhere */
- cmdstatus[0] = NUL;
- memcpy(&cmdstatus[1], &tuple, sizeof(tuple));
-
- return res;
-}
-
-/*
-**
-** set_result
-**
-*/
-void
-set_result(PGresult *newres)
-{
-
- char *cmdstatus = PQcmdStatus(res);
-
- if (newres == NULL)
- halt("set_result called with null result pointer\n");
-
- if (res != NULL && was_get_unset_result == FALSE)
- if (in_result_block == FALSE)
- PQclear(res);
- else
- {
- cmdstatus[0] = NUL;
- memcpy(&cmdstatus[1], &tuple, sizeof(tuple));
- }
-
- in_result_block = TRUE;
- was_get_unset_result = FALSE;
-
- cmdstatus = PQcmdStatus(newres);
- memcpy(&tuple, &cmdstatus[1], sizeof(tuple));
-
- res = newres;
-}
-
-
-/*
-**
-** unset_result
-**
-*/
-void
-unset_result(PGresult *oldres)
-{
- char *cmdstatus = PQcmdStatus(oldres);
-
- if (oldres == NULL)
- halt("unset_result called with null result pointer\n");
-
- if (in_result_block == FALSE)
- halt("Unset of result without being set.\n");
-
- was_get_unset_result = TRUE;
- cmdstatus[0] = NUL;
- memcpy(&cmdstatus[1], &tuple, sizeof(tuple));
- in_result_block = FALSE;
-}
-
-/*
-**
-** reset_fetch
-**
-*/
-void
-reset_fetch()
-{
- tuple = 0;
-}
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