vfork.S 649 B

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  1. #include <asm/unistd.h>
  2. #ifndef __NR_vfork
  3. #define __NR_vfork __NR_fork /* uClinux-2.0 only has fork which is vfork */
  4. #endif
  5. #define IMM #
  6. .text
  7. .align 2
  8. .globl errno
  9. .globl vfork
  10. .type vfork,@function
  11. vfork:
  12. movl %sp@+, %a1 /* save the return address for later */
  13. movl IMM __NR_vfork,%d0
  14. trap #0
  15. movl IMM -4097, %d1
  16. cmpl %d0, %d1
  17. bcs fix_errno
  18. jmp %a1@ /* don't return, just jmp directly */
  19. fix_errno:
  20. negl %d0
  21. #ifndef __PIC__
  22. movl errno, %a0
  23. #else
  24. movl errno@GOT(%a5), %a0
  25. #endif
  26. movl %d0, %a0@
  27. movl IMM -1, %d0
  28. jmp %a1@ /* don't return, just jmp directly */