fixup! shell: watch for R updates

src/shell/info.c

@@ -68,8 +68,14 @@ static flux_future_t *lookup_jobspec (flux_t *h, flux_jobid_t jobid)
     return f;
 }
 
-static void resource_watch_update (struct shell_info *info)
+/*  Unpack R from a job-info.update-watch response and update the
+ *  shell's internal info->R and info->rcalc. If a response can't be
+ *  unpacked or rcalc_create_json() fails, just ignore this response
+ *  and let caller decide if the error is fatal.
+ */
+static int resource_watch_update (struct shell_info *info)
 {
+    int rc = -1;
     flux_future_t *f = info->R_watch_future;
     json_t *R = NULL;
     json_t *tmp_R;
@@ -93,17 +99,20 @@ static void resource_watch_update (struct shell_info *info)
     tmp_rcalc = info->rcalc;
     info->rcalc = rcalc;
     rcalc = tmp_rcalc;
+    rc = 0;
 out:
     rcalc_destroy (rcalc);
     json_decref (R);
     flux_future_reset (f);
+    return rc;
 }
 
 static void R_update_cb (flux_future_t *f, void *arg)
 {
     flux_shell_t *shell = arg;
 
-    resource_watch_update (shell->info);
+    if (resource_watch_update (shell->info) < 0)
+        return;
 
     /*  Destroy cached shell "info" JSON object otherwise plugins will
      *  not see the updated R
@@ -174,9 +183,11 @@ static int shell_init_jobinfo (flux_shell_t *shell, struct shell_info *info)
         goto out;
     }
 
-    /*  Get initial version of R from initial job-info watch response:
+    /*  Synchronously get initial version of R from first job-info
+     *  watch response:
      */
-    resource_watch_update (info);
+    if (resource_watch_update (info) < 0)
+        goto out;
 
     /*  Register callback for future R updates:
      */