api: vppapitrace JSON/API trace converter

usage: vppapitrace.py [-h] [--debug] [--apidir APIDIR] {convert,replay} ...

optional arguments:
  -h, --help        show this help message and exit
  --debug           enable debug mode
  --apidir APIDIR   Location of JSON API definitions

subcommands:
  valid subcommands

  {convert,replay}  additional help
    convert         Convert API trace to JSON or Python and back
    replay          Replay messages to running VPP instance

To convert an API trace file to JSON:
vppapitrace convert /tmp/api.trace trace.json

To convert an (edited) JSON file back to API trace for replay:
vppapitrace convert trace.json api-edited.trace

To generate a Python file that can be replayed:
vppapitrace convert /tmp/api.trace trace.py
vppapitrace convert trace.json trace.py

Replay it to a running VPP instance:
vppapitrace replay --socket /tmp/api.trace

In VPP that file can be replayed with:
vpp# api trace replay api-edited.trace

This patch also modifies the API binary trace format, to include the
message id to message name table.

Change-Id: Ie6441efb53c1c93c9f778f6ae9c1758bccc8dd87
Type: refactor
Signed-off-by: Ole Troan <ot@cisco.com>

2 files changed, 36 insertions, 4 deletions

diff --git a/src/vlibapi/api.h b/src/vlibapi/api.h
index 7238a31f2f3..3eef0503310 100644
--- a/src/vlibapi/api.h
+++ b/src/vlibapi/api.h
@@ -30,9 +30,9 @@
 
 /* *INDENT-OFF* */
 typedef CLIB_PACKED ( struct {
-   u8 endian;
-   u8 wrapped;
    u32 nitems;
+   u32 msgtbl_size;
+   u8 wrapped;
 }) vl_api_trace_file_header_t;
 /* *INDENT-ON* */
 
diff --git a/src/vlibapi/api_shared.c b/src/vlibapi/api_shared.c
index 355be35c677..ce7c4aec712 100644
--- a/src/vlibapi/api_shared.c
+++ b/src/vlibapi/api_shared.c
@@ -189,6 +189,29 @@ vl_msg_api_trace_free (api_main_t * am, vl_api_trace_which_t which)
   return 0;
 }
 
+u8 *
+vl_api_serialize_message_table (api_main_t * am, u8 * vector)
+{
+  serialize_main_t _sm, *sm = &_sm;
+  hash_pair_t *hp;
+  u32 nmsg = hash_elts (am->msg_index_by_name_and_crc);
+
+  serialize_open_vector (sm, vector);
+
+  /* serialize the count */
+  serialize_integer (sm, nmsg, sizeof (u32));
+
+  /* *INDENT-OFF* */
+  hash_foreach_pair (hp, am->msg_index_by_name_and_crc,
+  ({
+    serialize_likely_small_unsigned_integer (sm, hp->value[0]);
+    serialize_cstring (sm, (char *) hp->key);
+  }));
+  /* *INDENT-ON* */
+
+  return serialize_close_vector (sm);
+}
+
 int
 vl_msg_api_trace_save (api_main_t * am, vl_api_trace_which_t which, FILE * fp)
 {
@@ -223,15 +246,24 @@ vl_msg_api_trace_save (api_main_t * am, vl_api_trace_which_t which, FILE * fp)
     }
 
   /* Write the file header */
-  fh.nitems = vec_len (tp->traces);
-  fh.endian = tp->endian;
   fh.wrapped = tp->wrapped;
+  fh.nitems = clib_host_to_net_u32 (vec_len (tp->traces));
+  u8 *m = vl_api_serialize_message_table (am, 0);
+  clib_warning ("Message table length %d", vec_len (m));
+  fh.msgtbl_size = clib_host_to_net_u32 (vec_len (m));
 
   if (fwrite (&fh, sizeof (fh), 1, fp) != 1)
     {
       return (-10);
     }
 
+  /* Write the message table */
+  if (fwrite (m, vec_len (m), 1, fp) != 1)
+    {
+      return (-14);
+    }
+  vec_free (m);
+
   /* No-wrap case */
   if (tp->wrapped == 0)
     {