Fri, Jul 15, 2016 at 09:29:55AM CEST, jo...@kernel.org wrote:
>Jirka reported that python code returns all arrays as strings.
>This makes impossible to get all items for byte array tracepoint
>field containing 0x00 value item.
>
>Fixing this by scanning full length of the array and returning
>it as PyByteArray object in case non printable byte is found.
>
>Cc: Steven Rostedt (Red Hat) <rost...@goodmis.org>
>Cc: Jiri Pirko <j...@mellanox.com>
>Link: http://lkml.kernel.org/n/tip-22f4vhhz5uytegkggy1on...@git.kernel.org
>Signed-off-by: Jiri Olsa <jo...@kernel.org>
>---
> .../util/scripting-engines/trace-event-python.c | 37 ++++++++++++++++++----
> 1 file changed, 31 insertions(+), 6 deletions(-)
>
>diff --git a/tools/perf/util/scripting-engines/trace-event-python.c
>b/tools/perf/util/scripting-engines/trace-event-python.c
>index 6ac6b7a33f42..1bc995de5a6d 100644
>--- a/tools/perf/util/scripting-engines/trace-event-python.c
>+++ b/tools/perf/util/scripting-engines/trace-event-python.c
>@@ -386,6 +386,19 @@ exit:
> return pylist;
> }
>
>+static int is_printable_array(char *p, unsigned int len)
>+{
>+ unsigned int i;
>+
>+ if (p[len - 1] == 0)
>+ len--;
>+
>+ for (i = 0; i < len - 1; i++)
>+ if (!isprint(p[i]) && !isspace(p[i]))
>+ return 0;
for "AA\1\0" this returns "1" although that should return "0".
orig len 4
decremented len 3
for:
0 1
index 2 would not be inspected. Or am I missing something?
I think that the for check should be "i < len"
Thanks.
>+
>+ return 1;
>+}
>
> static void python_process_tracepoint(struct perf_sample *sample,
> struct perf_evsel *evsel,
>@@ -457,14 +470,26 @@ static void python_process_tracepoint(struct perf_sample
>*sample,
> pydict_set_item_string_decref(dict, "common_callchain",
> callchain);
> }
> for (field = event->format.fields; field; field = field->next) {
>- if (field->flags & FIELD_IS_STRING) {
>- int offset;
>+ unsigned int offset, len;
>+ unsigned long long val;
>+
>+ if (field->flags & FIELD_IS_ARRAY) {
>+ offset = field->offset;
>+ len = field->size;
> if (field->flags & FIELD_IS_DYNAMIC) {
>- offset = *(int *)(data + field->offset);
>+ val =
>pevent_read_number(scripting_context->pevent,
>+ data + offset,
>len);
>+ offset = val;
>+ len = offset >> 16;
> offset &= 0xffff;
>- } else
>- offset = field->offset;
>- obj = PyString_FromString((char *)data + offset);
>+ }
>+ if (field->flags & FIELD_IS_STRING &&
>+ is_printable_array(data + offset, len)) {
>+ obj = PyString_FromString((char *) data +
>offset);
>+ } else {
>+ obj = PyByteArray_FromStringAndSize((const char
>*) data + offset, len);
>+ field->flags &= ~FIELD_IS_STRING;
>+ }
> } else { /* FIELD_IS_NUMERIC */
> obj = get_field_numeric_entry(event, field, data);
> }
>--
>2.4.11
>
