Pass in a buffer to olm_session_describe

instead of having a static one, as that could end up taking up a
lot of memory if your app keeps olm sessions hanging about.

1 files changed, 10 insertions, 4 deletions

diff --git a/javascript/olm_post.js b/javascript/olm_post.js
index c0498db..e204f30 100644
--- a/javascript/olm_post.js
+++ b/javascript/olm_post.js
@@ -460,10 +460,16 @@ Session.prototype['decrypt'] = restore_stack(function(
 });
 
 Session.prototype['describe'] = restore_stack(function() {
-    var description_buf = session_method(Module['_olm_session_describe'])(
-        this.ptr
-    );
-    return UTF8ToString(description_buf);
+    var description_buf;
+    try {
+        description_buf = malloc(256);
+        session_method(Module['_olm_session_describe'])(
+            this.ptr, description_buf, 256
+        );
+        return UTF8ToString(description_buf);
+    } finally {
+        if (description_buf !== undefined) free(description_buf);
+    }
 });
 
 function Utility() {