Replace old PostODBC driver with new one...

This one is based on an older PostODBC driver, rewritten and maintained by
InsightDist(?)

src/interfaces/odbc/columninfo.c

@@ -0,0 +1,159 @@
+
+/* Module:          columninfo.c
+ *
+ * Description:     This module contains routines related to 
+ *                  reading and storing the field information from a query.
+ *
+ * Classes:         ColumnInfoClass (Functions prefix: "CI_")
+ *
+ * API functions:   none
+ *
+ * Comments:        See "notice.txt" for copyright and license information.
+ *
+ */
+
+#include "columninfo.h"
+#include "socket.h"
+#include <stdlib.h>
+#include <malloc.h>
+
+ColumnInfoClass *
+CI_Constructor()
+{
+ColumnInfoClass *rv;
+
+	rv = (ColumnInfoClass *) malloc(sizeof(ColumnInfoClass));
+
+	if (rv) {
+		rv->num_fields = 0;
+		rv->name = NULL;
+		rv->adtid = NULL;
+		rv->adtsize = NULL;
+	}
+
+	return rv;
+}
+
+void
+CI_Destructor(ColumnInfoClass *self)
+{
+	CI_free_memory(self);
+
+	free(self);
+}
+
+/*  Read in field descriptions.
+    If self is not null, then also store the information.
+	If self is null, then just read, don't store.
+*/
+char
+CI_read_fields(ColumnInfoClass *self, SocketClass *sock)
+{
+Int2 lf;
+int new_num_fields;
+Oid new_adtid;
+Int2 new_adtsize;
+char new_field_name[MAX_MESSAGE_LEN+1];
+
+
+	/* at first read in the number of fields that are in the query */
+	new_num_fields = (Int2) SOCK_get_int(sock, sizeof(Int2));
+
+	mylog("num_fields = %d\n", new_num_fields);
+
+	if (self) { 	/* according to that allocate memory */
+		CI_set_num_fields(self, new_num_fields);
+	}
+
+	/* now read in the descriptions */
+	for(lf = 0; lf < new_num_fields; lf++) {
+
+		SOCK_get_string(sock, new_field_name, MAX_MESSAGE_LEN);
+		new_adtid = (Oid) SOCK_get_int(sock, 4);
+		new_adtsize = (Int2) SOCK_get_int(sock, 2);
+
+		mylog("CI_read_fields: fieldname='%s', adtid=%d, adtsize=%d\n", new_field_name, new_adtid, new_adtsize);
+
+		if (self)
+			CI_set_field_info(self, lf, new_field_name, new_adtid, new_adtsize);
+	}
+
+	return (SOCK_get_errcode(sock) == 0);
+}
+
+
+
+void
+CI_free_memory(ColumnInfoClass *self)
+{
+register Int2 lf;
+int num_fields = self->num_fields;
+
+	for (lf = 0; lf < num_fields; lf++) {
+		if( self->name[lf])
+			free (self->name[lf]);
+	}
+
+	/*	Safe to call even if null */
+	free(self->name);
+	free(self->adtid);
+	free(self->adtsize);
+}
+
+void
+CI_set_num_fields(ColumnInfoClass *self, int new_num_fields)
+{
+	CI_free_memory(self);	/* always safe to call */
+
+	self->num_fields = new_num_fields;
+
+	self->name = (char **) malloc (sizeof(char *) * self->num_fields);
+	self->adtid = (Oid *) malloc (sizeof(Oid) * self->num_fields);
+	self->adtsize = (Int2 *) malloc (sizeof(Int2) * self->num_fields);
+}
+
+void
+CI_set_field_info(ColumnInfoClass *self, int field_num, char *new_name, 
+                                      Oid new_adtid, Int2 new_adtsize)
+{
+    
+	// check bounds
+	if((field_num < 0) || (field_num >= self->num_fields)) {
+		return;
+	}
+
+	// store the info
+	self->name[field_num] = strdup(new_name);  
+	self->adtid[field_num] = new_adtid;
+	self->adtsize[field_num] = new_adtsize;
+}
+
+char *
+CI_get_fieldname(ColumnInfoClass *self, Int2 which)
+{
+char *rv = NULL;
+    
+	if ( ! self->name)
+		return NULL;
+
+	if ((which >= 0) && (which < self->num_fields))
+		rv = self->name[which];
+
+	return rv;
+}
+
+
+Int2
+CI_get_fieldsize(ColumnInfoClass *self, Int2 which)
+{
+Int2 rv = 0;
+
+	if ( ! self->adtsize)
+		return 0;
+
+	if ((which >= 0) && (which < self->num_fields))
+		rv = self->adtsize[which];
+
+	return rv;
+}
+