From 3108dd1c76ab57f1e4462c691cd6d015eb65f4eb Mon Sep 17 00:00:00 2001
From: Alexander Sulfrian <alexander@sulfrian.net>
Date: Wed, 7 Dec 2011 19:00:19 +0100
Subject: freeing PGresult just after executing a query

do not save PGresult anymore, just calculate the maybe needed values
(modified row count, last inserted id) and freeing PGresult afterwards
---
 ts3db.c | 58 ++++++++++++++++++++++------------------------------------
 1 file changed, 22 insertions(+), 36 deletions(-)

(limited to 'ts3db.c')

diff --git a/ts3db.c b/ts3db.c
index 70eb152..b264b8a 100644
--- a/ts3db.c
+++ b/ts3db.c
@@ -8,7 +8,8 @@
 
 typedef struct {
     PGconn *conn;
-    PGresult *result;
+    unsigned long long modified_rows;
+    unsigned long long last_inserted_id;
 } pg_connection;
 
 static log_callback log = 0;
@@ -37,7 +38,6 @@ int ts3dbplugin_disconnect()
 {
     unsigned int i;
     for (i = 0; i < connection_count; i++) {
-        PQclear(connections[i].result);
         PQfinish(connections[i].conn);
     }
 
@@ -98,7 +98,8 @@ int ts3dbplugin_connect(unsigned int *connection_nr)
 
     *connection_nr = connection_count;
     connections[connection_count].conn = conn;
-    connections[connection_count].result = NULL;
+    connections[connection_count].modified_rows = 0;
+    connections[connection_count].last_inserted_id = 0;
     connection_count++;
 
     return 0;
@@ -114,28 +115,28 @@ PGconn *get_connection(unsigned int connection_nr)
     return connections[connection_nr].conn;
 }
 
-PGresult *get_last_result(unsigned int connection_nr)
-{
-    if (connection_nr >= connection_count) {
-        log("Connection not found.", LOG_ERROR);
-        return NULL;
-    }
-
-    return connections[connection_nr].result;
-}
-
 void save_last_result(unsigned int connection_nr, PGresult *result)
 {
+    const char *rows, *last_id;
     if (connection_nr >= connection_count) {
         log("Connection not found.", LOG_ERROR);
         return;
     }
 
-    if (connections[connection_nr].result != NULL) {
-        PQclear(connections[connection_nr].result);
-    }
+    connections[connection_nr].modified_rows = 0;
+    connections[connection_nr].last_inserted_id = 0;
+
+    rows = PQcmdTuples(result);
+    sscanf(rows, "%llu", &connections[connection_nr].modified_rows);
+
+    if (PQnfields(result) == 1) {
+        if (strcmp(PQfname(result, 0), "last_inserted_id") == 0) {
+            last_id = PQgetvalue(result, 0, 0);
 
-    connections[connection_nr].result = result;
+            log(last_id, LOG_ERROR);
+            sscanf(last_id, "%llu", &connections[connection_nr].last_inserted_id);
+        }
+    }
 }
 
 char *ts3dbplugin_getlasterror(unsigned int connection_nr)
@@ -173,30 +174,13 @@ unsigned int ts3dbplugin_tableexists(unsigned int connection_nr, const char* tab
 unsigned long long ts3dbplugin_getmodifiedrowcount(unsigned int connection_nr)
 {
     log("getmodifiedrowcount", LOG_DEVELOP);
-    PGresult *result = get_last_result(connection_nr);
-    const char *count = PQcmdTuples(result);
-    unsigned long long number;
-
-    sscanf(count, "%llu", &number);
-    return number;
+    return connections[connection_nr].modified_rows;
 }
 
 unsigned long long ts3dbplugin_getlastinsertid(unsigned int connection_nr)
 {
     log("getlastinsertid", LOG_DEVELOP);
-    const PGresult *result = get_last_result(connection_nr);
-
-    if (PQnfields(result) == 1) {
-        if (strcmp(PQfname(result, 0), "last_inserted_id") == 0) {
-            const char *count = PQgetvalue(result, 0, 0);
-            unsigned long long number;
-
-            sscanf(count, "%llu", &number);
-            return number;
-        }
-    }
-
-    return 0;
+    return connections[connection_nr].last_inserted_id;
 }
 
 unsigned int ts3dbplugin_open(unsigned int connection_nr, const char* query,
@@ -239,6 +223,7 @@ unsigned int ts3dbplugin_open(unsigned int connection_nr, const char* query,
         }
     }
 
+    PQclear(result);
     return 0;
 }
 
@@ -261,5 +246,6 @@ unsigned int ts3dbplugin_exec(unsigned int connection_nr, const char* query)
         log(PQresultErrorMessage(result), LOG_WARNING);
     }
 
+    PQclear(result);
     return 0;
 }
-- 
cgit v1.2.3