On Sun, 10 Jul 2016 13:08:02 +0200 Jiri Olsa <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> > Reported-and-tested-by: 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 | 34 > ++++++++++++++++++---- > 1 file changed, 28 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 ff134700bf30..75e9790ebb96 100644 > --- a/tools/perf/util/scripting-engines/trace-event-python.c > +++ b/tools/perf/util/scripting-engines/trace-event-python.c > @@ -386,6 +386,16 @@ exit: > return pylist; > } > > +static int is_printable_array(char *p, unsigned int len) > +{ > + unsigned int i; > + > + for (i = 0; i < len; i++) > + if (!isprint(p[i]) && !isspace(p[i])) > + return 0; I believe this will return the wrong result if you pass in a string that has '\0' in it. Try it out: char a[] = "hello"; printf("a=%s is %d\n", a, is_printable_array(a, sizeof(a))); and see what you get? -- Steve > + > + return 1; > +} > > static void python_process_tracepoint(struct perf_sample *sample, > struct perf_evsel *evsel, > @@ -457,14 +467,26 @@ 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); > }
