Currently methods which want to iterate over trace events, do so using the trace_event_count() and trace_event_id() methods. This leaks the concept of a single ID enum to the callers. There is an alternative trace_event_pattern() method which can be used in an iteration context, but its design is stateless, so is not easy to expand it in the future.
This defines a formal iterator API will provide an future proof way of iterating over events. The iterator is also able to apply a pattern match filter to events, further removing the need for the pattern Signed-off-by: Daniel P. Berrange <[email protected]> --- trace/control.c | 26 ++++++++++++++++++++++++++ trace/control.h | 9 +++++++++ 2 files changed, 35 insertions(+) diff --git a/trace/control.c b/trace/control.c index d173c09..deab872 100644 --- a/trace/control.c +++ b/trace/control.c @@ -124,6 +124,32 @@ TraceEvent *trace_event_pattern(const char *pat, TraceEvent *ev) return NULL; } +void trace_event_iter_init(TraceEventIter *iter, const char *pattern) +{ + iter->event = 0; + iter->pattern = pattern; +} + +TraceEvent *trace_event_iter_next(TraceEventIter *iter) +{ + TraceEvent *ev; + + if (iter->event >= TRACE_EVENT_COUNT) { + return NULL; + } + + ev = &(trace_events[iter->event]); + + do { + iter->event++; + } while (iter->event < TRACE_EVENT_COUNT && + iter->pattern && + !pattern_glob(iter->pattern, + trace_event_get_name(&(trace_events[iter->event])))); + + return ev; +} + void trace_list_events(void) { int i; diff --git a/trace/control.h b/trace/control.h index 0413b28..a3a8a78 100644 --- a/trace/control.h +++ b/trace/control.h @@ -13,6 +13,10 @@ #include "qemu-common.h" #include "trace/generated-events.h" +typedef struct TraceEventIter { + size_t event; + const char *pattern; +} TraceEventIter; /** * TraceEventID: @@ -25,6 +29,11 @@ */ enum TraceEventID; + +void trace_event_iter_init(TraceEventIter *iter, const char *pattern); + +TraceEvent *trace_event_iter_next(TraceEventIter *iter); + /** * trace_event_id: * @id: Event identifier. -- 2.7.4
