Correctly compare queries

queries.c

@@ -115,8 +115,24 @@ struct send_file {
   int channel;
 };
 
-#define memcmp8(a,b) memcmp ((a), (b), 8)
-DEFINE_TREE (query, struct query *, memcmp8, 0) ;
+static int cmp_ll (long long a, long long b) {
+  /* Careful: don't convert to int!
+   * This does NOT always work correctly (although you'll never see the edge cases):
+   * return a - b; */
+  if (a > b) {
+      return 1;
+  } else if (a < b) {
+      return -1;
+  } else {
+      return 0;
+  }
+}
+static int cmp_query (struct query *a, struct query *b) {
+  int ret = cmp_ll (a->msg_id);
+  ret = ret ? ret : cmp_ll(a->session_id, b->session_id);
+  return ret;
+}
+DEFINE_TREE (query, struct query *, cmp_query, 0) ;
 
 static int mystreq1 (const char *a, const char *b, int l) {
   if ((int)strlen (a) != l) { return 1; }