module Kernel

VALUE
lineprof(VALUE self, VALUE filename)
{
  if (!rb_block_given_p())
    rb_raise(rb_eArgError, "block required");

  if (rblineprof.enabled)
    rb_raise(rb_eArgError, "profiler is already enabled");

  VALUE filename_class = rb_obj_class(filename);

  if (filename_class == rb_cString) {
#ifdef RUBY_VM
    rblineprof.source_filename = (char *) (StringValuePtr(filename));
#else
    /* rb_source_filename will return a string we can compare directly against
     * node->file, without a strcmp()
     */
    rblineprof.source_filename = rb_source_filename(StringValuePtr(filename));
#endif
  } else if (filename_class == rb_cRegexp) {
    rblineprof.source_regex = filename;
    rblineprof.source_filename = NULL;
  } else {
    rb_raise(rb_eArgError, "argument must be String or Regexp");
  }

  // reset state
  st_foreach(rblineprof.files, cleanup_files, 0);
  if (rblineprof.file.lines) {
    xfree(rblineprof.file.lines);
    rblineprof.file.lines = NULL;
    rblineprof.file.nlines = 0;
  }
  rblineprof.cache.file = NULL;
  rblineprof.cache.srcfile = NULL;

  rblineprof.enabled = true;
#ifndef RUBY_VM
  rb_add_event_hook((rb_event_hook_func_t) profiler_hook, RUBY_EVENT_CALL|RUBY_EVENT_RETURN|RUBY_EVENT_C_CALL|RUBY_EVENT_C_RETURN);
#else
  rb_add_event_hook((rb_event_hook_func_t) profiler_hook, RUBY_EVENT_CALL|RUBY_EVENT_RETURN|RUBY_EVENT_C_CALL|RUBY_EVENT_C_RETURN, Qnil);
#endif

  rb_ensure(rb_yield, Qnil, lineprof_ensure, self);

  VALUE ret = rb_hash_new();

  if (rblineprof.source_filename) {
    summarize_files(Qnil, (st_data_t)&rblineprof.file, ret);
  } else {
    st_foreach(rblineprof.files, summarize_files, ret);
  }

  return ret;
}