swapcontext.c 1.2 KB

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  1. /* Copyright (C) 2001-2013 Free Software Foundation, Inc.
  2. Contributed by David Mosberger-Tang <davidm@hpl.hp.com>.
  3. The GNU C Library is free software; you can redistribute it and/or
  4. modify it under the terms of the GNU Lesser General Public
  5. License as published by the Free Software Foundation; either
  6. version 2.1 of the License, or (at your option) any later version.
  7. The GNU C Library is distributed in the hope that it will be useful,
  8. but WITHOUT ANY WARRANTY; without even the implied warranty of
  9. MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
  10. Lesser General Public License for more details.
  11. You should have received a copy of the GNU Lesser General Public
  12. License along with the GNU C Library; if not, see
  13. <http://www.gnu.org/licenses/>. */
  14. #include <ucontext.h>
  15. struct rv
  16. {
  17. long retval;
  18. long first_return;
  19. };
  20. extern struct rv __getcontext (ucontext_t *__ucp);
  21. extern int __setcontext (const ucontext_t *__ucp);
  22. int
  23. __swapcontext (ucontext_t *oucp, const ucontext_t *ucp)
  24. {
  25. struct rv rv = __getcontext (oucp);
  26. if (rv.first_return)
  27. __setcontext (ucp);
  28. return 0;
  29. }
  30. weak_alias (__swapcontext, swapcontext)