unit-tests/test-cases/big-stack/main.c

   1 /*
   2  * Copyright (c) 2006-2012 Apple Inc. All rights reserved.
   3  *
   4  * @APPLE_LICENSE_HEADER_START@
   5  *
   6  * This file contains Original Code and/or Modifications of Original Code
   7  * as defined in and that are subject to the Apple Public Source License
   8  * Version 2.0 (the 'License'). You may not use this file except in
   9  * compliance with the License. Please obtain a copy of the License at
  10  * http://www.opensource.apple.com/apsl/ and read it before using this
  11  * file.
  12  *
  13  * The Original Code and all software distributed under the License are
  14  * distributed on an 'AS IS' basis, WITHOUT WARRANTY OF ANY KIND, EITHER
  15  * EXPRESS OR IMPLIED, AND APPLE HEREBY DISCLAIMS ALL SUCH WARRANTIES,
  16  * INCLUDING WITHOUT LIMITATION, ANY WARRANTIES OF MERCHANTABILITY,
  17  * FITNESS FOR A PARTICULAR PURPOSE, QUIET ENJOYMENT OR NON-INFRINGEMENT.
  18  * Please see the License for the specific language governing rights and
  19  * limitations under the License.
  20  *
  21  * @APPLE_LICENSE_HEADER_END@
  22  */
  23 #include <stdlib.h> // EXIT_SUCCESS
  24 #include <mach-o/dyld.h>
  25 #include <sys/sysctl.h>
  26 #include <unistd.h>
  27
  28 #include "test.h"
  29
  30 //
  31 // This builds an executable that needs > 2GB of stack
  32 //
  33
  34
  35 char* keepAlive;        // to keep compiler from optimizing away stack variable
  36
  37 // keep recursing until desired stack size achieved
  38 void foo(unsigned long long stackSize, char* stackStart)
  39 {
  40         char buffer[32*1024*1024];
  41         keepAlive = buffer;
  42         // only recursive if there is enough room for next buffer
  43         intptr_t freeStackSpace = (buffer - sizeof(buffer)) - (stackStart - stackSize);
  44         //fprintf(stderr, "&buffer=%p, stackStart=%p, freeStackSpace=0x%lx\n", buffer, stackStart, freeStackSpace);
  45         if ( freeStackSpace < sizeof(buffer) )
  46                 return;
  47         else
  48                 foo(stackSize, stackStart);
  49 }
  50
  51
  52 int
  53 main()
  54 {
  55         char start;
  56   foo(STACK_SIZE, &start);
  57         return EXIT_SUCCESS;
  58 }
  59
  60