/* UnwindProtect.m
 *
 * Copyright Niels Möller <nisse@lysator.liu.se> 1995
 *
 * Freely distributable under the terms and conditions of the
 * GNU General Public License.
 */


#include <UnwindProtect.h>


/* I'm not sure if I should hardcode StackFrame here or not. */
#ifndef FRAME_STACK
#define FRAME_STACK [self class]
#endif FRAME_STACK


@implementation UnwindProtect 
- init
{
  [ [self initDontFree] cleanupBySending: @selector(rawFree) to: self];
  return self;
}


- initDontFree
{
  [super init];
  frame = NULL;
  return self;
}


- cleanupByCalling: ( void (*)(void)) function
{
  frame_id newFrame = [FRAME_STACK pushProtectCall: function];
  if (!frame)
    frame = newFrame;
  return self;
}


- cleanupBySending: (SEL) message to: rec
{
  frame_id newFrame = [FRAME_STACK pushProtect: rec send: message];
  if (!frame)
    frame = newFrame;
  return self;
}


- (void) cleanup
{
  /* This cleanup may send me the free message, so copy the
   * instance variable first. */

  frame_id oldFrame = frame;
  frame = NULL;
  
  if (oldFrame)
    {
      [FRAME_STACK unwind: oldFrame];
      [FRAME_STACK freeFrame: oldFrame];
    }
}
@end /* UnwindProtect */