Fixed a bug where a value past the end of an array could be read

(though it would never be used).


git-svn-id: svn://svn.code.sf.net/p/sc2/code/trunk@1417 8092fc87-c524-0410-9efc-e669fe64eaf9

sc2/src/sc2code/libs/uio/hashtable.c

@@ -230,18 +230,26 @@ nextPower2(uio_uint32 x) {
 //       there are outstanding iterators.
 HASHTABLE_(Iterator) *
 HASHTABLE_(getIterator)(const HASHTABLE_(HashTable) *hashTable) {
-	HASHTABLE_(Iterator) *result;
+	HASHTABLE_(Iterator) *iterator;
 	uio_uint32 i;
 
-	result = uio_malloc(sizeof (HASHTABLE_(Iterator)));
-	result->hashTable = hashTable;
-	i = 0;	
-	while (i < hashTable->size &&
-			hashTable->entries[i] == NULL)
-		i++;
-	result->bucketNr = i;
-	result->entry = hashTable->entries[i];
-	return result;
+	iterator = uio_malloc(sizeof (HASHTABLE_(Iterator)));
+	iterator->hashTable = hashTable;
+	
+	// Look for the first used bucket.
+	for (i = 0; i < iterator->hashTable->size; i++) {
+		if (iterator->hashTable->entries[i] != NULL) {
+			// Found a used bucket.
+			iterator->bucketNr = i;
+			iterator->entry = iterator->hashTable->entries[i];
+			return iterator;
+		}
+	}
+
+	// No entries were found.
+	iterator->bucketNr = i;
+	iterator->entry = NULL;
+	return iterator;
 }
 
 int
@@ -259,22 +267,29 @@ HASHTABLE_(iteratorValue)(HASHTABLE_(Iterator) *iterator) {
 	return iterator->entry->value;
 }
 
+// Should not be called if the iterator is already past the last entry.
 HASHTABLE_(Iterator) *
 HASHTABLE_(iteratorNext)(HASHTABLE_(Iterator) *iterator) {
 	uio_uint32 i;
 
-	if (iterator->entry != NULL) {
-		iterator->entry = iterator->entry->next;
-		if (iterator->entry != NULL)
+	// If there's another entry in this bucket, use that.
+	iterator->entry = iterator->entry->next;
+	if (iterator->entry != NULL)
+		return iterator;
+
+	// Look for the next used bucket.
+	for (i = iterator->bucketNr + 1; i < iterator->hashTable->size; i++) {
+		if (iterator->hashTable->entries[i] != NULL) {
+			// Found another used bucket.
+			iterator->bucketNr = i;
+			iterator->entry = iterator->hashTable->entries[i];
 			return iterator;
+		}
 	}
 
-	i = iterator->bucketNr + 1;
-	while (i < iterator->hashTable->size &&
-			iterator->hashTable->entries[i] == NULL)
-		i++;
+	// No more entries were found.
 	iterator->bucketNr = i;
-	iterator->entry = iterator->hashTable->entries[i];
+	iterator->entry = NULL;
 	return iterator;
 }