nptl/pthread_cleanup_upto.c

   1 /* Copyright (C) 2002-2022 Free Software Foundation, Inc.
   2    This file is part of the GNU C Library.
   3
   4    The GNU C Library is free software; you can redistribute it and/or
   5    modify it under the terms of the GNU Lesser General Public
   6    License as published by the Free Software Foundation; either
   7    version 2.1 of the License, or (at your option) any later version.
   8
   9    The GNU C Library is distributed in the hope that it will be useful,
  10    but WITHOUT ANY WARRANTY; without even the implied warranty of
  11    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  12    Lesser General Public License for more details.
  13
  14    You should have received a copy of the GNU Lesser General Public
  15    License along with the GNU C Library; if not, see
  16    <https://www.gnu.org/licenses/>.  */
  17
  18 #include <setjmp.h>
  19 #include <stdlib.h>
  20 #include "pthreadP.h"
  21 #include <jmpbuf-unwind.h>
  22
  23 void
  24 __pthread_cleanup_upto (__jmp_buf target, char *targetframe)
  25 {
  26   struct pthread *self = THREAD_SELF;
  27   struct _pthread_cleanup_buffer *cbuf;
  28
  29   /* Adjust all pointers used in comparisons, so that top of thread's
  30      stack is at the top of address space.  Without that, things break
  31      if stack is allocated above the main stack.  */
  32   uintptr_t adj = (uintptr_t) self->stackblock + self->stackblock_size;
  33   uintptr_t targetframe_adj = (uintptr_t) targetframe - adj;
  34
  35   for (cbuf = THREAD_GETMEM (self, cleanup);
  36        cbuf != NULL && _JMPBUF_UNWINDS_ADJ (target, cbuf, adj);
  37        cbuf = cbuf->__prev)
  38     {
  39 #if _STACK_GROWS_DOWN
  40       if ((uintptr_t) cbuf - adj <= targetframe_adj)
  41         {
  42           cbuf = NULL;
  43           break;
  44         }
  45 #elif _STACK_GROWS_UP
  46       if ((uintptr_t) cbuf - adj >= targetframe_adj)
  47         {
  48           cbuf = NULL;
  49           break;
  50         }
  51 #else
  52 # error "Define either _STACK_GROWS_DOWN or _STACK_GROWS_UP"
  53 #endif
  54
  55       /* Call the cleanup code.  */
  56       cbuf->__routine (cbuf->__arg);
  57     }
  58
  59   THREAD_SETMEM (self, cleanup, cbuf);
  60 }
  61 libc_hidden_def (__pthread_cleanup_upto)