From af403073f055323ce72efcce4e990c0c52743c92 Mon Sep 17 00:00:00 2001
From: Christophe CURIS <christophe.curis@free.fr>
Date: Wed, 8 May 2013 15:44:12 +0200
Subject: [PATCH] Fixed memory leak due to non-freed property list structure

The history is actually loaded from a file into a property list that
is then converted to an array. The intermediate property list was
not freed, which led to memory leak.

It looks like it was a tentative of optimisation to avoid duplicating
an already allocated string and re-use the pointer instead, but this
means it is not possible to free the original container as it would
free the string too.

There is a better way to do this, but it requires an API change on the
WUtil library so it is left for a future improvment.
---
 src/dialog.c | 32 +++++++++++++++++++++++---------
 1 file changed, 23 insertions(+), 9 deletions(-)

diff --git a/src/dialog.c b/src/dialog.c
index 05087474..7b0b4f28 100644
--- a/src/dialog.c
+++ b/src/dialog.c
@@ -191,24 +191,38 @@ static WMArray *LoadHistory(const char *filename, int max)
 	WMPropList *plitem;
 	WMArray *history;
 	int i, num;
+	char *str;
 
 	history = WMCreateArrayWithDestructor(1, wfree);
 	WMAddToArray(history, wstrdup(""));
 
 	plhistory = WMReadPropListFromFile(filename);
 
-	if (plhistory && WMIsPLArray(plhistory)) {
-		num = WMGetPropListItemCount(plhistory);
+	if (plhistory) {
+		if (WMIsPLArray(plhistory)) {
+			num = WMGetPropListItemCount(plhistory);
 
-		for (i = 0; i < num; ++i) {
-			plitem = WMGetFromPLArray(plhistory, i);
-			if (WMIsPLString(plitem) && WMFindInArray(history, strmatch,
-								  WMGetFromPLString(plitem)) == WANotFound) {
-				WMAddToArray(history, WMGetFromPLString(plitem));
-				if (--max <= 0)
-					break;
+			for (i = 0; i < num; ++i) {
+				plitem = WMGetFromPLArray(plhistory, i);
+				if (WMIsPLString(plitem)) {
+					str = WMGetFromPLString(plitem);
+					if (WMFindInArray(history, strmatch, str) == WANotFound) {
+						/*
+						 * The string here is duplicated because it will be freed
+						 * automatically when the array is deleted. This is not really
+						 * great because it is already an allocated string,
+						 * unfortunately we cannot re-use it because it will be freed
+						 * when we discard the PL (and we don't want to waste the PL's
+						 * memory either)
+						 */
+						WMAddToArray(history, wstrdup(str));
+						if (--max <= 0)
+							break;
+					}
+				}
 			}
 		}
+		WMReleasePropList(plhistory);
 	}
 
 	return history;