Make fgets not use maximal buffer length always, but shrink buffer

if it's too big.

ext/standard/file.c

@@ -990,6 +990,10 @@ PHP_FUNCTION(fgets)
 		} else {
 			return_value->value.str.val = buf;
 			return_value->value.str.len = strlen(return_value->value.str.val);
+			/* resize buffer if it's much larger than the result */
+			if(return_value->value.str.len < len/2) {
+				return_value->value.str.val = erealloc(buf,return_value->value.str.len);
+			}
 		}
 		return_value->type = IS_STRING;
 	}