mirror of
https://github.com/postgres/postgres.git
synced 2025-07-27 12:41:57 +03:00
Improve libpgeasy API for multiple result sets, add example.
This commit is contained in:
Bruce Momjian
@ -4,23 +4,17 @@
|
||||
# Makefile for pgeasy examples
|
||||
#
|
||||
# IDENTIFICATION
|
||||
# $Header: /cvsroot/pgsql/src/interfaces/libpgeasy/examples/Attic/Makefile,v 1.2 2000/05/18 14:24:37 momjian Exp $
|
||||
# $Header: /cvsroot/pgsql/src/interfaces/libpgeasy/examples/Attic/Makefile,v 1.3 2002/03/04 18:50:21 momjian Exp $
|
||||
#
|
||||
#-------------------------------------------------------------------------
|
||||
|
||||
CFLAGS=-I/usr/local/pgsql/include
|
||||
TARGET = pginsert pgwordcount pgnulltest
|
||||
TARGET = pginsert pgwordcount pgnulltest pgmultiresult
|
||||
LDFLAGS = -L/usr/local/pgsql/lib -lpgeasy
|
||||
|
||||
all : $(TARGET)
|
||||
|
||||
pginsert:
|
||||
gcc -o $@ $(CFLAGS) $@.c $(PGEASY) $(LDFLAGS)
|
||||
|
||||
pgwordcount:
|
||||
gcc -o $@ $(CFLAGS) $@.c $(PGEASY) $(LDFLAGS)
|
||||
|
||||
pgnulltest:
|
||||
%: %.c
|
||||
gcc -o $@ $(CFLAGS) $@.c $(PGEASY) $(LDFLAGS)
|
||||
|
||||
clean:
|
||||
|
||||
@ -6,6 +6,7 @@
|
||||
#include <stdio.h>
|
||||
#include <string.h>
|
||||
#include <stdarg.h>
|
||||
#include <stdlib.h>
|
||||
|
||||
#include "libpq-fe.h"
|
||||
#include "halt.h"
|
||||
@ -16,31 +17,33 @@
|
||||
#endif
|
||||
|
||||
#ifndef TRUE
|
||||
#define TRUE 1
|
||||
#define TRUE 1
|
||||
#endif
|
||||
|
||||
#ifndef FALSE
|
||||
#define FALSE 0
|
||||
#define FALSE 0
|
||||
#endif
|
||||
|
||||
/* GLOBAL VARIABLES */
|
||||
static PGconn *conn;
|
||||
static PGresult *res = NULL;
|
||||
|
||||
static int tuple; /* stores fetch location */
|
||||
static int tuple; /* stores fetch location */
|
||||
|
||||
#define ON_ERROR_STOP 0
|
||||
#define ON_ERROR_CONTINUE 1
|
||||
#define ON_ERROR_STOP 0
|
||||
#define ON_ERROR_CONTINUE 1
|
||||
|
||||
static int on_error_state = ON_ERROR_STOP; /* halt on errors? */
|
||||
static int on_error_state = ON_ERROR_STOP; /* halt on errors? */
|
||||
|
||||
static int user_has_res = FALSE;
|
||||
|
||||
static void add_res_tuple(void);
|
||||
static void get_res_tuple(void);
|
||||
static void del_res_tuple(void);
|
||||
|
||||
static int in_result_block = FALSE;
|
||||
static int was_get_unset_result = FALSE;
|
||||
|
||||
/*
|
||||
*
|
||||
* connectdb - returns PGconn structure
|
||||
*
|
||||
*/
|
||||
PGconn *
|
||||
connectdb(char *options)
|
||||
@ -53,17 +56,14 @@ connectdb(char *options)
|
||||
return conn;
|
||||
}
|
||||
|
||||
|
||||
/*
|
||||
*
|
||||
* disconnectdb
|
||||
*
|
||||
*/
|
||||
void
|
||||
disconnectdb()
|
||||
{
|
||||
if (res != NULL &&
|
||||
in_result_block == FALSE &&
|
||||
was_get_unset_result == FALSE)
|
||||
if (res != NULL && user_has_res == FALSE)
|
||||
{
|
||||
PQclear(res);
|
||||
res = NULL;
|
||||
@ -72,20 +72,17 @@ disconnectdb()
|
||||
PQfinish(conn);
|
||||
}
|
||||
|
||||
|
||||
/*
|
||||
*
|
||||
* doquery - returns PGresult structure
|
||||
*
|
||||
*/
|
||||
PGresult *
|
||||
doquery(char *query)
|
||||
{
|
||||
if (res != NULL &&
|
||||
in_result_block == FALSE &&
|
||||
was_get_unset_result == FALSE)
|
||||
if (res != NULL && user_has_res == FALSE)
|
||||
PQclear(res);
|
||||
|
||||
was_get_unset_result = FALSE;
|
||||
user_has_res = FALSE;
|
||||
res = PQexec(conn, query);
|
||||
|
||||
if (on_error_state == ON_ERROR_STOP &&
|
||||
@ -105,11 +102,10 @@ doquery(char *query)
|
||||
return res;
|
||||
}
|
||||
|
||||
|
||||
/*
|
||||
*
|
||||
* fetch - returns tuple number (starts at 0), or the value END_OF_TUPLES
|
||||
* NULL pointers are skipped
|
||||
*
|
||||
*/
|
||||
int
|
||||
fetch(void *param,...)
|
||||
@ -142,8 +138,8 @@ fetch(void *param,...)
|
||||
return tuple++;
|
||||
}
|
||||
|
||||
|
||||
/*
|
||||
*
|
||||
* fetchwithnulls - returns tuple number (starts at 0),
|
||||
* or the value END_OF_TUPLES
|
||||
* Returns TRUE or FALSE into null indicator variables
|
||||
@ -185,10 +181,19 @@ fetchwithnulls(void *param,...)
|
||||
return tuple++;
|
||||
}
|
||||
|
||||
|
||||
/*
|
||||
* reset_fetch
|
||||
*/
|
||||
void
|
||||
reset_fetch()
|
||||
{
|
||||
tuple = 0;
|
||||
}
|
||||
|
||||
|
||||
/*
|
||||
*
|
||||
* on_error_stop
|
||||
*
|
||||
*/
|
||||
void
|
||||
on_error_stop()
|
||||
@ -196,10 +201,9 @@ on_error_stop()
|
||||
on_error_state = ON_ERROR_STOP;
|
||||
}
|
||||
|
||||
|
||||
/*
|
||||
*
|
||||
* on_error_continue
|
||||
*
|
||||
*/
|
||||
void
|
||||
on_error_continue()
|
||||
@ -209,92 +213,132 @@ on_error_continue()
|
||||
|
||||
|
||||
/*
|
||||
*
|
||||
* get_result
|
||||
*
|
||||
*/
|
||||
PGresult *
|
||||
get_result()
|
||||
{
|
||||
char *cmdstatus = PQcmdStatus(res);
|
||||
if (res == NULL)
|
||||
halt("get_result called with no result pointer used\n");
|
||||
|
||||
was_get_unset_result = TRUE;
|
||||
/* delete it if it is already there; we are about to re-add it */
|
||||
del_res_tuple();
|
||||
|
||||
/* we have to store the fetch location somewhere */
|
||||
/* XXX THIS IS A NO-NO */
|
||||
cmdstatus[0] = NUL;
|
||||
memcpy(&cmdstatus[1], &tuple, sizeof(tuple));
|
||||
/* we have to store the fetch location */
|
||||
add_res_tuple();
|
||||
|
||||
user_has_res = TRUE;
|
||||
|
||||
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 (res != NULL && user_has_res == FALSE)
|
||||
{
|
||||
if (in_result_block == FALSE)
|
||||
PQclear(res);
|
||||
else
|
||||
{
|
||||
/* XXX THIS IS A NO-NO */
|
||||
cmdstatus[0] = NUL;
|
||||
memcpy(&cmdstatus[1], &tuple, sizeof(tuple));
|
||||
}
|
||||
/*
|
||||
* Basically, throw away res. We can't return to it because the
|
||||
* user doesn't have the res pointer.
|
||||
*/
|
||||
del_res_tuple();
|
||||
PQclear(res);
|
||||
}
|
||||
|
||||
in_result_block = TRUE;
|
||||
was_get_unset_result = FALSE;
|
||||
|
||||
cmdstatus = PQcmdStatus(newres);
|
||||
memcpy(&tuple, &cmdstatus[1], sizeof(tuple));
|
||||
user_has_res = FALSE;
|
||||
|
||||
res = newres;
|
||||
|
||||
get_res_tuple();
|
||||
}
|
||||
|
||||
|
||||
/*
|
||||
*
|
||||
* unset_result
|
||||
*
|
||||
* Routines to store res/tuple mapping
|
||||
* This is used to keep track of fetch locations while using get/set on
|
||||
* result sets.
|
||||
* Auto-growing array is used, with empty slots marked by res == NULL
|
||||
*/
|
||||
void
|
||||
unset_result(PGresult *oldres)
|
||||
|
||||
static struct res_tuple
|
||||
{
|
||||
char *cmdstatus = PQcmdStatus(oldres);
|
||||
PGresult *res;
|
||||
int tuple;
|
||||
} *res_tuple = NULL;
|
||||
|
||||
if (oldres == NULL)
|
||||
halt("unset_result called with null result pointer\n");
|
||||
static int res_tuple_len = 0;
|
||||
|
||||
if (in_result_block == FALSE)
|
||||
halt("Unset of result without being set.\n");
|
||||
|
||||
was_get_unset_result = TRUE;
|
||||
|
||||
/* XXX THIS IS A NO-NO */
|
||||
cmdstatus[0] = NUL;
|
||||
memcpy(&cmdstatus[1], &tuple, sizeof(tuple));
|
||||
in_result_block = FALSE;
|
||||
}
|
||||
|
||||
/*
|
||||
*
|
||||
* reset_fetch
|
||||
*
|
||||
* add_res_tuple
|
||||
*/
|
||||
void
|
||||
reset_fetch()
|
||||
static void
|
||||
add_res_tuple(void)
|
||||
{
|
||||
tuple = 0;
|
||||
int i,
|
||||
new_res_tuple_len = res_tuple_len ? res_tuple_len * 2 : 1;
|
||||
|
||||
for (i = 0; i < res_tuple_len; i++)
|
||||
/* Put it in an empty slot */
|
||||
if (res_tuple[i].res == NULL)
|
||||
{
|
||||
res_tuple[i].res = res;
|
||||
res_tuple[i].tuple = tuple;
|
||||
}
|
||||
|
||||
/* Need to grow array */
|
||||
res_tuple = realloc(res_tuple, new_res_tuple_len * sizeof(struct res_tuple));
|
||||
|
||||
/* clear new elements */
|
||||
for (i = res_tuple_len; i < new_res_tuple_len; i++)
|
||||
{
|
||||
res_tuple[i].res = NULL;
|
||||
res_tuple[i].tuple = 0;
|
||||
}
|
||||
|
||||
/* recursion to add entry */
|
||||
add_res_tuple();
|
||||
}
|
||||
|
||||
|
||||
/*
|
||||
* get_res_tuple
|
||||
*/
|
||||
static void
|
||||
get_res_tuple(void)
|
||||
{
|
||||
int i;
|
||||
|
||||
for (i = 0; i < res_tuple_len; i++)
|
||||
if (res_tuple[i].res == res)
|
||||
{
|
||||
tuple = res_tuple[i].tuple;
|
||||
return;
|
||||
}
|
||||
halt("get_res_tuple called with invalid result pointer\n");
|
||||
}
|
||||
|
||||
|
||||
/*
|
||||
* del_res_tuple
|
||||
*/
|
||||
static void
|
||||
del_res_tuple(void)
|
||||
{
|
||||
int i;
|
||||
|
||||
for (i = 0; i < res_tuple_len; i++)
|
||||
if (res_tuple[i].res == res)
|
||||
{
|
||||
res_tuple[i].res = NULL;
|
||||
return;
|
||||
}
|
||||
return;
|
||||
}
|
||||
|
||||
Reference in New Issue
Block a user