libgcc/config/gthr-vxworks.h

   1 /* Threads compatibility routines for libgcc2 and libobjc for VxWorks.  */
   2 /* Compile this one with gcc.  */
   3 /* Copyright (C) 1997-2018 Free Software Foundation, Inc.
   4    Contributed by Mike Stump <mrs@wrs.com>.
   5
   6 This file is part of GCC.
   7
   8 GCC is free software; you can redistribute it and/or modify it under
   9 the terms of the GNU General Public License as published by the Free
  10 Software Foundation; either version 3, or (at your option) any later
  11 version.
  12
  13 GCC is distributed in the hope that it will be useful, but WITHOUT ANY
  14 WARRANTY; without even the implied warranty of MERCHANTABILITY or
  15 FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
  16 for more details.
  17
  18 Under Section 7 of GPL version 3, you are granted additional
  19 permissions described in the GCC Runtime Library Exception, version
  20 3.1, as published by the Free Software Foundation.
  21
  22 You should have received a copy of the GNU General Public License and
  23 a copy of the GCC Runtime Library Exception along with this program;
  24 see the files COPYING3 and COPYING.RUNTIME respectively.  If not, see
  25 <http://www.gnu.org/licenses/>.  */
  26
  27 #ifndef GCC_GTHR_VXWORKS_H
  28 #define GCC_GTHR_VXWORKS_H
  29
  30 #ifdef _LIBOBJC
  31
  32 /* libobjc requires the optional pthreads component.  */
  33 #include "gthr-posix.h"
  34
  35 #else
  36 #ifdef __cplusplus
  37 #define UNUSED(x)
  38 #else
  39 #define UNUSED(x) x __attribute__((__unused__))
  40 #endif
  41
  42 #ifdef __cplusplus
  43 extern "C" {
  44 #endif
  45
  46 #define __GTHREADS 1
  47 #define __gthread_active_p() 1
  48
  49 /* Mutexes are easy, except that they need to be initialized at runtime.  */
  50
  51 #include <semLib.h>
  52
  53 typedef SEM_ID __gthread_mutex_t;
  54 /* All VxWorks mutexes are recursive.  */
  55 typedef SEM_ID __gthread_recursive_mutex_t;
  56 #define __GTHREAD_MUTEX_INIT_FUNCTION __gthread_mutex_init_function
  57 #define __GTHREAD_RECURSIVE_MUTEX_INIT_FUNCTION __gthread_recursive_mutex_init_function
  58
  59 static inline void
  60 __gthread_mutex_init_function (__gthread_mutex_t *mutex)
  61 {
  62   *mutex = semMCreate (SEM_Q_PRIORITY | SEM_INVERSION_SAFE | SEM_DELETE_SAFE);
  63 }
  64
  65 static inline int
  66 __gthread_mutex_destroy (__gthread_mutex_t * UNUSED(mutex))
  67 {
  68   return 0;
  69 }
  70
  71 static inline int
  72 __gthread_mutex_lock (__gthread_mutex_t *mutex)
  73 {
  74   return semTake (*mutex, WAIT_FOREVER);
  75 }
  76
  77 static inline int
  78 __gthread_mutex_trylock (__gthread_mutex_t *mutex)
  79 {
  80   return semTake (*mutex, NO_WAIT);
  81 }
  82
  83 static inline int
  84 __gthread_mutex_unlock (__gthread_mutex_t *mutex)
  85 {
  86   return semGive (*mutex);
  87 }
  88
  89 static inline void
  90 __gthread_recursive_mutex_init_function (__gthread_recursive_mutex_t *mutex)
  91 {
  92   __gthread_mutex_init_function (mutex);
  93 }
  94
  95 static inline int
  96 __gthread_recursive_mutex_lock (__gthread_recursive_mutex_t *mutex)
  97 {
  98   return __gthread_mutex_lock (mutex);
  99 }
 100
 101 static inline int
 102 __gthread_recursive_mutex_trylock (__gthread_recursive_mutex_t *mutex)
 103 {
 104   return __gthread_mutex_trylock (mutex);
 105 }
 106
 107 static inline int
 108 __gthread_recursive_mutex_unlock (__gthread_recursive_mutex_t *mutex)
 109 {
 110   return __gthread_mutex_unlock (mutex);
 111 }
 112
 113 static inline int
 114 __gthread_recursive_mutex_destroy (__gthread_recursive_mutex_t *__mutex)
 115 {
 116   return __gthread_mutex_destroy (__mutex);
 117 }
 118
 119 /* pthread_once is complicated enough that it's implemented
 120    out-of-line.  See config/vxlib.c.  */
 121
 122 typedef struct
 123 {
 124 #if !defined(__RTP__)
 125 #if defined(__PPC__)
 126   __attribute ((aligned (__alignof (unsigned))))
 127 #endif
 128   volatile unsigned char busy;
 129 #endif
 130   volatile unsigned char done;
 131 #if !defined(__RTP__) && defined(__PPC__)
 132   /* PPC's test-and-set implementation requires a 4 byte aligned
 133      object, of which it only sets the first byte.  We use padding
 134      here, in order to maintain some amount of backwards
 135      compatibility.  Without this padding, gthread_once objects worked
 136      by accident because they happen to be static objects and the ppc
 137      port automatically increased their alignment to 4 bytes.  */
 138   unsigned char pad1;
 139   unsigned char pad2;
 140 #endif
 141 }
 142 __gthread_once_t;
 143
 144 #if defined (__RTP__)
 145 # define __GTHREAD_ONCE_INIT { 0 }
 146 #elif defined (__PPC__)
 147 # define __GTHREAD_ONCE_INIT { 0, 0, 0, 0 }
 148 #else
 149 # define __GTHREAD_ONCE_INIT { 0, 0 }
 150 #endif
 151
 152 extern int __gthread_once (__gthread_once_t *__once, void (*__func)(void));
 153
 154 /* Thread-specific data requires a great deal of effort, since VxWorks
 155    is not really set up for it.  See config/vxlib.c for the gory
 156    details.  All the TSD routines are sufficiently complex that they
 157    need to be implemented out of line.  */
 158
 159 typedef unsigned int __gthread_key_t;
 160
 161 extern int __gthread_key_create (__gthread_key_t *__keyp, void (*__dtor)(void *));
 162 extern int __gthread_key_delete (__gthread_key_t __key);
 163
 164 extern void *__gthread_getspecific (__gthread_key_t __key);
 165 extern int __gthread_setspecific (__gthread_key_t __key, void *__ptr);
 166
 167 #undef UNUSED
 168
 169 #ifdef __cplusplus
 170 }
 171 #endif
 172
 173 #endif /* not _LIBOBJC */
 174
 175 #endif /* gthr-vxworks.h */