From abb2a393308bdfe62814bef19a185ee5423b8a6e Mon Sep 17 00:00:00 2001
From: Andrew Bettison <andrew@servalproject.org>
Date: Mon, 29 Jun 2015 14:52:29 +0930
Subject: [PATCH] Fix MeshMS REST newsince race condition

During GET /restful/meshms/SID1/SID2/newsince/messagelist.json, if a new
message was received before the request reached the end of its message
iterator and paused, then the new message did not make it into the
output.
---
 httpd.h          |  1 +
 meshms.c         |  7 +++++++
 meshms_restful.c | 12 ++++++++++--
 3 files changed, 18 insertions(+), 2 deletions(-)

diff --git a/httpd.h b/httpd.h
index 5a80aac1..a3c1b5d1 100644
--- a/httpd.h
+++ b/httpd.h
@@ -188,6 +188,7 @@ typedef struct httpd_request
       enum list_phase phase;
       size_t rowcount;
       struct meshms_message_iterator iter;
+      unsigned dirty;
       int finished;
     }
       msglist;
diff --git a/meshms.c b/meshms.c
index 6258d128..ec941644 100644
--- a/meshms.c
+++ b/meshms.c
@@ -785,6 +785,11 @@ void meshms_conversation_iterator_advance(struct meshms_conversation_iterator *i
 
 enum meshms_status meshms_message_iterator_open(struct meshms_message_iterator *iter, const sid_t *me, const sid_t *them)
 {
+  if (config.debug.meshms)
+    DEBUGF("iter=%p me=%s them=%s", iter,
+	  me ? alloca_tohex_sid_t(*me) : "NULL",
+	  them ? alloca_tohex_sid_t(*them) : "NULL"
+	);
   enum meshms_status status;
   bzero(iter, sizeof *iter);
   if (meshms_failed(status = find_or_create_conv(me, them, &iter->_conv)))
@@ -842,6 +847,8 @@ int meshms_message_iterator_is_open(const struct meshms_message_iterator *iter)
 
 void meshms_message_iterator_close(struct meshms_message_iterator *iter)
 {
+  if (config.debug.meshms)
+    DEBUGF("iter=%p", iter);
   if (iter->_my_manifest) {
     ply_read_close(&iter->_my_reader);
     rhizome_manifest_free(iter->_my_manifest);
diff --git a/meshms_restful.c b/meshms_restful.c
index a3298bb6..d559816d 100644
--- a/meshms_restful.c
+++ b/meshms_restful.c
@@ -290,6 +290,10 @@ static HTTP_CONTENT_GENERATOR restful_meshms_messagelist_json_content;
 
 static enum meshms_status reopen_meshms_message_iterator(httpd_request *r)
 {
+  if (r->u.msglist.dirty) {
+    meshms_message_iterator_close(&r->u.msglist.iter);
+    r->u.msglist.dirty = 0;
+  }
   if (!meshms_message_iterator_is_open(&r->u.msglist.iter)) {
     enum meshms_status status;
     if (   meshms_failed(status = meshms_message_iterator_open(&r->u.msglist.iter, &r->sid1, &r->sid2))
@@ -352,9 +356,13 @@ static int restful_meshms_newsince_messagelist_json(httpd_request *r, const char
 
 static void on_rhizome_bundle_added(httpd_request *r, rhizome_manifest *m)
 {
-  // TODO select on sender and/or recipient fields
   if (strcmp(m->service, RHIZOME_SERVICE_MESHMS2) == 0) {
-    http_request_resume_response(&r->http);
+    if (   (cmp_sid_t(&m->sender, &r->sid1) == 0 && cmp_sid_t(&m->recipient, &r->sid2) == 0)
+	|| (cmp_sid_t(&m->sender, &r->sid2) == 0 && cmp_sid_t(&m->recipient, &r->sid1) == 0)
+    ) {
+      r->u.msglist.dirty = 1;
+      http_request_resume_response(&r->http);
+    }
   }
 }