diff --git a/doc/src/sgml/libpgeasy.sgml b/doc/src/sgml/libpgeasy.sgml
index 9196621c8c..4bb1b7949b 100644
--- a/doc/src/sgml/libpgeasy.sgml
+++ b/doc/src/sgml/libpgeasy.sgml
@@ -1,5 +1,5 @@
@@ -11,7 +11,7 @@ $Header: /cvsroot/pgsql/doc/src/sgml/Attic/libpgeasy.sgml,v 2.8 2002/01/07 02:29
Written by Bruce Momjian
(pgman@candle.pha.pa.us)
- and last updated 2000-03-30
+ and last updated 2002-03-04
@@ -19,13 +19,12 @@ $Header: /cvsroot/pgsql/doc/src/sgml/Attic/libpgeasy.sgml,v 2.8 2002/01/07 02:29
pgeasy allows you to cleanly interface
to the libpq library, more like a 4GL
SQL interface. Refer to for more
- information about libpq
+ information about libpq.
- It consists of set of simplified C functions that encapsulate the
- functionality of libpq.
- The functions are:
+ It consists of a set of simplified C functions that encapsulate the
+ functionality of libpq. The functions are:
@@ -88,53 +87,50 @@ void set_result(PGresult *newres);
-
-
-void unset_result(PGresult *oldres);
-
-
- Many functions return a structure or value, so you can do more work
+ Many functions return a structure or value, so you can work
with the result if required.
- You basically connect to the database with connectdb,
- issue your query with doquery,
- fetch the results with fetch,
- and finish with disconnectdb.
+ You basically connect to the database with
+ connectdb, issue your query with
+ doquery, fetch the results with
+ fetch, and finish with
+ disconnectdb.
For SELECT queries, 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 cannot be used if you are running the
- pgeasy
- client on a system with a different architecture than the database
- server. If you pass a NULL pointer parameter, the column is skipped.
- fetchwithnulls allows you to retrieve the NULL
- status of the field by passing an 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 doquery.
- reset_fetch starts the fetch back at the beginning.
+ 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 cannot be used if you are running the
+ pgeasy client on a system with a different
+ architecture than the database server. If you pass a NULL pointer
+ parameter, the column is skipped. fetchwithnulls
+ allows you to retrieve the NULL status of the field by passing an
+ int* after each result pointer, which returns true
+ or false to indicate if the field is null. You can always use
+ libpq functions on the
+ PGresult pointer returned by
+ doquery. reset_fetch starts
+ the fetch back at the beginning.
- get_result,
- set_result,
- and
- unset_result
- allow you to handle multiple result sets at the same time.
+ get_result and set_result
+ allow you to handle multiple open result sets. Use
+ get_result to save a result into an application
+ variable. You can then later use set_result to
+ return to the previously save result.
- There are several demonstration programs in the
- source directory.
+ There are several demonstration programs in
+ pgsql/src/interfaces/libpgeasy/examples.
diff --git a/src/interfaces/libpgeasy/examples/Makefile b/src/interfaces/libpgeasy/examples/Makefile
index 1885bb425f..af8dc0c32a 100644
--- a/src/interfaces/libpgeasy/examples/Makefile
+++ b/src/interfaces/libpgeasy/examples/Makefile
@@ -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:
diff --git a/src/interfaces/libpgeasy/libpgeasy.c b/src/interfaces/libpgeasy/libpgeasy.c
index 4bddece659..40684a2cfe 100644
--- a/src/interfaces/libpgeasy/libpgeasy.c
+++ b/src/interfaces/libpgeasy/libpgeasy.c
@@ -6,6 +6,7 @@
#include
#include
#include
+#include
#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;
}