libogc/semaphore.c

   1 /*-------------------------------------------------------------
   2
   3 semaphore.c -- Thread subsystem IV
   4
   5 Copyright (C) 2004
   6 Michael Wiedenbauer (shagkur)
   7 Dave Murphy (WinterMute)
   8
   9 This software is provided 'as-is', without any express or implied
  10 warranty.  In no event will the authors be held liable for any
  11 damages arising from the use of this software.
  12
  13 Permission is granted to anyone to use this software for any
  14 purpose, including commercial applications, and to alter it and
  15 redistribute it freely, subject to the following restrictions:
  16
  17 1.      The origin of this software must not be misrepresented; you
  18 must not claim that you wrote the original software. If you use
  19 this software in a product, an acknowledgment in the product
  20 documentation would be appreciated but is not required.
  21
  22 2.      Altered source versions must be plainly marked as such, and
  23 must not be misrepresented as being the original software.
  24
  25 3.      This notice may not be removed or altered from any source
  26 distribution.
  27
  28
  29 -------------------------------------------------------------*/
  30
  31
  32 #include <stdlib.h>
  33 #include <errno.h>
  34 #include <asm.h>
  35 #include "lwp_sema.h"
  36 #include "lwp_objmgr.h"
  37 #include "lwp_config.h"
  38 #include "semaphore.h"
  39
  40 #define LWP_OBJTYPE_SEM                         4
  41
  42 #define LWP_CHECK_SEM(hndl)             \
  43 {                                                                       \
  44         if(((hndl)==LWP_SEM_NULL) || (LWP_OBJTYPE(hndl)!=LWP_OBJTYPE_SEM))      \
  45                 return NULL;                            \
  46 }
  47
  48
  49 typedef struct _sema_st
  50 {
  51         lwp_obj object;
  52         lwp_sema sema;
  53 } sema_st;
  54
  55 lwp_objinfo _lwp_sema_objects;
  56
  57 void __lwp_sema_init()
  58 {
  59         __lwp_objmgr_initinfo(&_lwp_sema_objects,LWP_MAX_SEMAS,sizeof(sema_st));
  60 }
  61
  62 static __inline__ sema_st* __lwp_sema_open(sem_t sem)
  63 {
  64         LWP_CHECK_SEM(sem);
  65         return (sema_st*)__lwp_objmgr_get(&_lwp_sema_objects,LWP_OBJMASKID(sem));
  66 }
  67
  68 static __inline__ void __lwp_sema_free(sema_st *sema)
  69 {
  70         __lwp_objmgr_close(&_lwp_sema_objects,&sema->object);
  71         __lwp_objmgr_free(&_lwp_sema_objects,&sema->object);
  72 }
  73
  74 static sema_st* __lwp_sema_allocate()
  75 {
  76         sema_st *sema;
  77
  78         __lwp_thread_dispatchdisable();
  79         sema = (sema_st*)__lwp_objmgr_allocate(&_lwp_sema_objects);
  80         if(sema) {
  81                 __lwp_objmgr_open(&_lwp_sema_objects,&sema->object);
  82                 return sema;
  83         }
  84         __lwp_thread_dispatchenable();
  85         return NULL;
  86 }
  87
  88 s32 LWP_SemInit(sem_t *sem,u32 start,u32 max)
  89 {
  90         lwp_semattr attr;
  91         sema_st *ret;
  92
  93         if(!sem) return -1;
  94
  95         ret = __lwp_sema_allocate();
  96         if(!ret) return -1;
  97
  98         attr.max_cnt = max;
  99         attr.mode = LWP_SEMA_MODEFIFO;
 100         __lwp_sema_initialize(&ret->sema,&attr,start);
 101
 102         *sem = (sem_t)(LWP_OBJMASKTYPE(LWP_OBJTYPE_SEM)|LWP_OBJMASKID(ret->object.id));
 103         __lwp_thread_dispatchenable();
 104         return 0;
 105 }
 106
 107 s32 LWP_SemWait(sem_t sem)
 108 {
 109         sema_st *lwp_sem;
 110
 111         lwp_sem = __lwp_sema_open(sem);
 112         if(!lwp_sem) return -1;
 113
 114         __lwp_sema_seize(&lwp_sem->sema,lwp_sem->object.id,TRUE,LWP_THREADQ_NOTIMEOUT);
 115         __lwp_thread_dispatchenable();
 116
 117         switch(_thr_executing->wait.ret_code) {
 118                 case LWP_SEMA_SUCCESSFUL:
 119                         break;
 120                 case LWP_SEMA_UNSATISFIED_NOWAIT:
 121                         return EAGAIN;
 122                 case LWP_SEMA_DELETED:
 123                         return EAGAIN;
 124                 case LWP_SEMA_TIMEOUT:
 125                         return ETIMEDOUT;
 126
 127         }
 128         return 0;
 129 }
 130
 131 s32 LWP_SemPost(sem_t sem)
 132 {
 133         sema_st *lwp_sem;
 134
 135         lwp_sem = __lwp_sema_open(sem);
 136         if(!lwp_sem) return -1;
 137
 138         __lwp_sema_surrender(&lwp_sem->sema,lwp_sem->object.id);
 139         __lwp_thread_dispatchenable();
 140
 141         return 0;
 142 }
 143
 144 s32 LWP_SemDestroy(sem_t sem)
 145 {
 146         sema_st *lwp_sem;
 147
 148         lwp_sem = __lwp_sema_open(sem);
 149         if(!lwp_sem) return -1;
 150
 151         __lwp_sema_flush(&lwp_sem->sema,-1);
 152         __lwp_thread_dispatchenable();
 153
 154         __lwp_sema_free(lwp_sem);
 155         return 0;
 156 }