#!/usr/sbin/dtrace -s

/* Usage: sudo ./trace_msg_send -p PID ClassName [filter-message…]
 *
 * E.g. messages send to Xcode classes that start with `DVTiPhoneSimulator`:
 *
 *   $ sudo ./trace_msg_send -p $(pgrep '^Xcode$') 'DVTiPhone*' name device \
 *   deviceType supportedArchitectures isAvailable operatingSystemVersion \
 *   supportedDeviceFamilies platform
*/

/* Based on: http://stackoverflow.com/questions/16238845/show-objective-c-class-in-dtrace-output/16242756#16242756 */

#pragma D option quiet
#pragma D option defaultargs

unsigned long long indention;
int indentation_amount;
int filter_methods[string];

BEGIN
{
  indentation_amount = 2;
  filter_methods[$$2] = 1;
  filter_methods[$$3] = 1;
  filter_methods[$$4] = 1;
  filter_methods[$$5] = 1;
  filter_methods[$$6] = 1;
  filter_methods[$$7] = 1;
  filter_methods[$$8] = 1;
  filter_methods[$$9] = 1;
}

objc$target:$1::*
{
  self->class = probemod;
  self->class_or_instance = probefunc[0];
  self->selector = (string)&probefunc[1];
}

objc$target:$1::entry
/filter_methods[self->selector] == 0/
{
    printf("%*s%s %c[%s %s]\n", indention * indentation_amount, "", "->", self->class_or_instance, self->class, self->selector);
    indention++;
}

objc$target:$1::return
/filter_methods[self->selector] == 0/
{
    indention--;
    printf("%*s%s %c[%s %s]\n", indention * indentation_amount, "", "<-", self->class_or_instance, self->class, self->selector);
}