YA corner case: help assumption by putting cancelled transactions first.

[ccan] / ccan / tdb / tools / replay_trace.c

diff --git a/ccan/tdb/tools/replay_trace.c b/ccan/tdb/tools/replay_trace.c
index 087bd876acfd636f3af218423d93ccd0dd4e9cee..4afe900aa8e8317587e2f4eb0d84572d74fc221b 100644 (file)
--- a/ccan/tdb/tools/replay_trace.c
+++ b/ccan/tdb/tools/replay_trace.c
@@ -962,6 +962,12 @@ static bool in_transaction(const struct op op[], unsigned int i)
        return op[i].group_start && starts_transaction(&op[op[i].group_start]);
 }
 
+static bool successful_transaction(const struct op *op)
+{
+       return starts_transaction(op)
+               && op[op->group_len].op == OP_TDB_TRANSACTION_COMMIT;
+}
+
 static bool starts_traverse(const struct op *op)
 {
        return op->op == OP_TDB_TRAVERSE_START
@@ -1265,8 +1271,21 @@ static void sort_ops(struct keyinfo hash[], char *filename[], struct op *op[],
                        return a->op_num - b->op_num;
 
                /* Otherwise, arrange by serial order. */
-               return op[a->file][a->op_num].serial
-                       - op[b->file][b->op_num].serial;
+               if (op[a->file][a->op_num].serial !=
+                   op[b->file][b->op_num].serial)
+                       return op[a->file][a->op_num].serial
+                               - op[b->file][b->op_num].serial;
+
+               /* Cancelled transactions are assumed to happen first. */
+               if (starts_transaction(&op[a->file][a->op_num])
+                   && !successful_transaction(&op[a->file][a->op_num]))
+                       return -1;
+               if (starts_transaction(&op[b->file][b->op_num])
+                   && !successful_transaction(&op[b->file][b->op_num]))
+                       return 1;
+
+               /* No idea. */
+               return 0;
        }
 
        /* Now sort into serial order. */