pthread_condattr_setpshared.c 3.8 KB

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  1. /*
  2. * pthread_condattr_setpshared.c
  3. *
  4. * Description:
  5. * This translation unit implements condition variables and their primitives.
  6. *
  7. *
  8. * --------------------------------------------------------------------------
  9. *
  10. * Pthreads-embedded (PTE) - POSIX Threads Library for embedded systems
  11. * Copyright(C) 2008 Jason Schmidlapp
  12. *
  13. * Contact Email: [email protected]
  14. *
  15. *
  16. * Based upon Pthreads-win32 - POSIX Threads Library for Win32
  17. * Copyright(C) 1998 John E. Bossom
  18. * Copyright(C) 1999,2005 Pthreads-win32 contributors
  19. *
  20. * Contact Email: [email protected]
  21. *
  22. * The original list of contributors to the Pthreads-win32 project
  23. * is contained in the file CONTRIBUTORS.ptw32 included with the
  24. * source code distribution. The list can also be seen at the
  25. * following World Wide Web location:
  26. * http://sources.redhat.com/pthreads-win32/contributors.html
  27. *
  28. * This library is free software; you can redistribute it and/or
  29. * modify it under the terms of the GNU Lesser General Public
  30. * License as published by the Free Software Foundation; either
  31. * version 2 of the License, or (at your option) any later version.
  32. *
  33. * This library is distributed in the hope that it will be useful,
  34. * but WITHOUT ANY WARRANTY; without even the implied warranty of
  35. * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
  36. * Lesser General Public License for more details.
  37. *
  38. * You should have received a copy of the GNU Lesser General Public
  39. * License along with this library in the file COPYING.LIB;
  40. * if not, write to the Free Software Foundation, Inc.,
  41. * 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA
  42. */
  43. #include "pthread.h"
  44. #include "implement.h"
  45. int
  46. pthread_condattr_setpshared (pthread_condattr_t * attr, int pshared)
  47. /*
  48. * ------------------------------------------------------
  49. * DOCPUBLIC
  50. * Mutexes created with 'attr' can be shared between
  51. * processes if pthread_mutex_t variable is allocated
  52. * in memory shared by these processes.
  53. *
  54. * PARAMETERS
  55. * attr
  56. * pointer to an instance of pthread_mutexattr_t
  57. *
  58. * pshared
  59. * must be one of:
  60. *
  61. * PTHREAD_PROCESS_SHARED
  62. * May be shared if in shared memory
  63. *
  64. * PTHREAD_PROCESS_PRIVATE
  65. * Cannot be shared.
  66. *
  67. * DESCRIPTION
  68. * Mutexes creatd with 'attr' can be shared between
  69. * processes if pthread_mutex_t variable is allocated
  70. * in memory shared by these processes.
  71. *
  72. * NOTES:
  73. * 1) pshared mutexes MUST be allocated in shared
  74. * memory.
  75. *
  76. * 2) The following macro is defined if shared mutexes
  77. * are supported:
  78. * _POSIX_THREAD_PROCESS_SHARED
  79. *
  80. * RESULTS
  81. * 0 successfully set attribute,
  82. * EINVAL 'attr' or pshared is invalid,
  83. * ENOSYS PTHREAD_PROCESS_SHARED not supported,
  84. *
  85. * ------------------------------------------------------
  86. */
  87. {
  88. int result;
  89. if ((attr != NULL && *attr != NULL)
  90. && ((pshared == PTHREAD_PROCESS_SHARED)
  91. || (pshared == PTHREAD_PROCESS_PRIVATE)))
  92. {
  93. if (pshared == PTHREAD_PROCESS_SHARED)
  94. {
  95. #if !defined( _POSIX_THREAD_PROCESS_SHARED )
  96. result = ENOSYS;
  97. pshared = PTHREAD_PROCESS_PRIVATE;
  98. #else
  99. result = 0;
  100. #endif /* _POSIX_THREAD_PROCESS_SHARED */
  101. }
  102. else
  103. {
  104. result = 0;
  105. }
  106. (*attr)->pshared = pshared;
  107. }
  108. else
  109. {
  110. result = EINVAL;
  111. }
  112. return result;
  113. } /* pthread_condattr_setpshared */