vfork.S 2.3 KB

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  1. /* Copyright (C) 2003 Free Software Foundation, Inc.
  2. This file is part of the GNU C Library.
  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, write to the Free
  13. Software Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA
  14. 02111-1307 USA. */
  15. #include <sysdep-cancel.h>
  16. #define _ERRNO_H 1
  17. #include <bits/errno.h>
  18. #include <bits/kernel-features.h>
  19. /* Clone the calling process, but without copying the whole address space.
  20. The calling process is suspended until the new process exits or is
  21. replaced by a call to `execve'. Return -1 for errors, 0 to the new process,
  22. and the process ID of the new process to the old process. */
  23. #ifdef SHARED
  24. .section ".toc","aw"
  25. .LC0:
  26. .tc __libc_pthread_functions[TC],__libc_pthread_functions
  27. .section ".text"
  28. .align 2
  29. #endif
  30. ENTRY (__vfork)
  31. #ifdef __NR_vfork
  32. # ifdef SHARED
  33. ld 10,.LC0@toc(2)
  34. ld 10,0(10)
  35. cmpwi 10,0
  36. bne- HIDDEN_JUMPTARGET(__fork)
  37. # else
  38. .weak pthread_create
  39. lis 10,pthread_create@highest
  40. ori 10,10,pthread_create@higher
  41. sldi 10,10,32
  42. oris 10,10,pthread_create@h
  43. ori 10,10,pthread_create@l
  44. cmpwi 10,0
  45. bne- .Lhidden_fork
  46. # endif
  47. DO_CALL (SYS_ify (vfork));
  48. # ifdef __ASSUME_VFORK_SYSCALL
  49. PSEUDO_RET
  50. # else
  51. bnslr+
  52. /* Check if vfork syscall is known at all. */
  53. cmpdi r3,ENOSYS
  54. # ifdef SHARED
  55. bne JUMPTARGET(__syscall_error)
  56. # else
  57. bne- .Lsyscall_error
  58. # endif
  59. # endif
  60. #endif
  61. #ifndef __ASSUME_VFORK_SYSCALL
  62. /* If we don't have vfork, fork is close enough. */
  63. DO_CALL (SYS_ify (fork));
  64. PSEUDO_RET
  65. #endif
  66. # ifndef SHARED
  67. .Lhidden_fork:
  68. b HIDDEN_JUMPTARGET(__fork)
  69. .Lsyscall_error:
  70. b JUMPTARGET(__syscall_error)
  71. # endif
  72. PSEUDO_END (__vfork)
  73. libc_hidden_def (__vfork)
  74. weak_alias (__vfork, vfork)