Re: [PATCH] store trace default-collect to target [3/6] tfile

[Hui Zhu <teawater at gmail dot com>]

Hi Yao,

Thanks for your patch.

I should do it but I didn't  because when I work on this part I cannot
find example in GDB src bceause the code that can be example is still
not check in.  :P

Best,
Hui

On Thu, Apr 11, 2013 at 8:53 PM, Yao Qi <yao@codesourcery.com> wrote:
> On 04/11/2013 02:17 PM, Hui Zhu wrote:
>>   /* This is the implementation of trace_file_write_ops method
>> +   write_default_collect.  */
>> +
>> +static void
>> +ctf_write_default_collect (struct trace_file_writer *self,
>> +                        char *collect)
>> +{
>> +  /* It is not supported yet to write default collect
>> +     into CTF trace data.  */
>> +}
>> +
>
> It is pity to see "default-collect" is not written to CTF in this
> patch.  The patch below is about teaching GDB to write
> "default-collect" action in CTF and read "default-collect" action from
> CTF.  Do you mind incorporating the patch below into your patch series,
> so that your series is more complete.
>
> --
> Yao (éå)
>
> gdb:
>
> 2013-04-11  Yao Qi  <yao@codesourcery.com>
>
>         * ctf.c (CTF_EVENT_ID_DEFAULT_COLLECT): New macro.
>         (ctf_write_header): Write metadata for "default-collect"
>         action.
>         (ctf_write_default_collect): Write "default-collect" action
>         in CTF.
>         (ctf_read_default_collect): New.
>         (ctf_open): Call ctf_read_default_collect.
> ---
>  gdb/ctf.c |   59 +++++++++++++++++++++++++++++++++++++++++++++++++++++++++--
>  1 files changed, 57 insertions(+), 2 deletions(-)
>
> diff --git a/gdb/ctf.c b/gdb/ctf.c
> index 2dd2ed8..5757b47 100644
> --- a/gdb/ctf.c
> +++ b/gdb/ctf.c
> @@ -74,6 +74,7 @@
>  #define CTF_EVENT_ID_STATUS 4
>  #define CTF_EVENT_ID_TSV_DEF 5
>  #define CTF_EVENT_ID_TP_DEF 6
> +#define CTF_EVENT_ID_DEFAULT_COLLECT 7
>
>  /* The state kept while writing the CTF datastream file.  */
>
> @@ -428,6 +429,16 @@ ctf_write_header (struct trace_file_writer *self)
>                           "\t};\n"
>                           "};\n", CTF_EVENT_ID_TP_DEF);
>
> +  ctf_save_write_metadata (&writer->tcs, "\n");
> +  ctf_save_write_metadata (&writer->tcs,
> +                          "event {\n\tname = \"default_collect\";\n"
> +                          "\tid = %u;\n"
> +                          "\tfields := struct { \n"
> +                          "\t\tchars contents;\n"
> +                          "\t};\n"
> +                          "};\n",
> +                          CTF_EVENT_ID_DEFAULT_COLLECT);
> +
>    gdb_assert (writer->tcs.content_size == 0);
>    gdb_assert (writer->tcs.packet_start == 0);
>
> @@ -622,8 +633,17 @@ static void
>  ctf_write_default_collect (struct trace_file_writer *self,
>                            char *collect)
>  {
> -  /* It is not supported yet to write default collect
> -     into CTF trace data.  */
> +  struct ctf_trace_file_writer *writer
> +    = (struct ctf_trace_file_writer *) self;
> +  int32_t int32;
> +
> +  /* Event Id.  */
> +  int32 = CTF_EVENT_ID_DEFAULT_COLLECT;
> +  ctf_save_align_write (&writer->tcs, (gdb_byte *) &int32, 4, 4);
> +
> +  /* Contents.  */
> +  ctf_save_write (&writer->tcs, collect, strlen (collect) + 1);
> +
>  }
>
>  /* This is the implementation of trace_file_write_ops method
> @@ -1149,6 +1169,39 @@ ctf_read_tp (struct uploaded_tp **uploaded_tps)
>      }
>  }
>
> +/* Read a CTF event on "default-collect" and update the
> +   "default-collect" action.  */
> +
> +static void
> +ctf_read_default_collect (void)
> +{
> +  struct bt_ctf_event *event;
> +  const struct bt_definition *scope;
> +  uint32_t u32;
> +  char *default_collect;
> +
> +  event = bt_ctf_iter_read_event (ctf_iter);
> +  scope = bt_ctf_get_top_level_scope (event,
> +                                     BT_STREAM_EVENT_HEADER);
> +  u32 = bt_ctf_get_uint64 (bt_ctf_get_field (event, scope,
> +                                            "id"));
> +
> +  if (u32 != CTF_EVENT_ID_DEFAULT_COLLECT)
> +    error (_("Wrong event id!"));
> +
> +  default_collect
> +    = bt_ctf_get_string (bt_ctf_get_field (event, scope, "contents"));
> +
> +  if (default_collect == NULL)
> +    default_collect = xstrdup ("");
> +  else
> +    default_collect = xstrdup (default_collect);
> +
> +  trace_set_default_collect (default_collect);
> +
> +  bt_iter_next (bt_ctf_get_iter (ctf_iter));
> +}
> +
>  /* This is the implementation of target_ops method to_open.  Open CTF
>     trace data, read trace status, trace state variables and tracepoint
>     definitions from the first packet.  Set the start position at the
> @@ -1190,6 +1243,8 @@ ctf_open (char *dirname, int from_tty)
>
>    ctf_read_tp (&uploaded_tps);
>
> +  ctf_read_default_collect ();
> +
>    event = bt_ctf_iter_read_event (ctf_iter);
>    /* EVENT can be NULL if we've already gone to the end of stream of
>       events.  */
> --
> 1.7.7.6