diff options
author | ko1 <ko1@b2dd03c8-39d4-4d8f-98ff-823fe69b080e> | 2015-04-15 08:40:25 +0000 |
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committer | ko1 <ko1@b2dd03c8-39d4-4d8f-98ff-823fe69b080e> | 2015-04-15 08:40:25 +0000 |
commit | 0e7889959191ba74307ef450817833164eddb9f4 (patch) | |
tree | c171afdc7df3162507e9d0e571e3201cc2eae264 /vm_trace.c | |
parent | d9a2b3480ef03b79ea9070de0646d2372491a915 (diff) |
* vm_trace.c (rb_tracepoint_new): Add documentation for
rb_tracepoint_new C level API [ci skip]
Provided by @emilsoman. [fix GH-869]
git-svn-id: svn+ssh://ci.ruby-lang.org/ruby/trunk@50321 b2dd03c8-39d4-4d8f-98ff-823fe69b080e
Diffstat (limited to 'vm_trace.c')
-rw-r--r-- | vm_trace.c | 30 |
1 files changed, 30 insertions, 0 deletions
diff --git a/vm_trace.c b/vm_trace.c index e50ea992f2..a186e0d364 100644 --- a/vm_trace.c +++ b/vm_trace.c @@ -1171,6 +1171,36 @@ tracepoint_new(VALUE klass, rb_thread_t *target_th, rb_event_flag_t events, void return tpval; } +/* + * Creates a tracepoint by registering a callback function for one or more + * tracepoint events. Once the tracepoint is created, you can use + * rb_tracepoint_enable to enable the tracepoint. + * + * Parameters: + * 1. VALUE target_thval - Meant for picking the thread in which the tracepoint + * is to be created. However, current implementation ignore this parameter, + * tracepoint is created for all threads. Simply specify Qnil. + * 2. rb_event_flag_t events - Event(s) to listen to. + * 3. void (*func)(VALUE, void *) - A callback function. + * 4. void *data - Void pointer that will be passed to the callback function. + * + * When the callback function is called, it will be passed 2 parameters: + * 1)VALUE tpval - the TracePoint object from which trace args can be extracted. + * 2)void *data - A void pointer which helps to share scope with the callback function. + * + * It is important to note that you cannot register callbacks for normal events and internal events + * simultaneously because they are different purpose. + * You can use any Ruby APIs (calling methods and so on) on normal event hooks. + * However, you can not use any Ruby APIs (even object creations). + * This is why we can't specify internal events by TracePoint directly. + * Limitations are MRI version specific. + * + * Example: + * rb_tracepoint_new(Qnil, RUBY_INTERNAL_EVENT_NEWOBJ | RUBY_INTERNAL_EVENT_FREEOBJ, obj_event_i, data); + * + * In this example, a callback function obj_event_i will be registered for + * internal events RUBY_INTERNAL_EVENT_NEWOBJ and RUBY_INTERNAL_EVENT_FREEOBJ. + */ VALUE rb_tracepoint_new(VALUE target_thval, rb_event_flag_t events, void (*func)(VALUE, void *), void *data) { |