1 #include "common.h" 2 #include <ddekit/condvar.h> 3 #include <ddekit/lock.h> 4 #include <ddekit/memory.h> 5 #include <ddekit/panic.h> 6 #include <ddekit/semaphore.h> 7 8 #ifdef DDEBUG_LEVEL_SEMAPHORE 9 #undef DDEBUG 10 #define DDEBUG DDEBUG_LEVEL_SEMAPHORE 11 #endif 12 13 #include "debug.h" 14 #include "thread.h" 15 16 struct ddekit_sem { 17 unsigned count; 18 ddekit_thread_t *wait_queue; 19 }; 20 21 #define SEM_DEBUG(p) \ 22 do { \ 23 DDEBUG_MSG_VERBOSE("%s, %p, %d\n",__func__, sem, sem->count); \ 24 } while(0) 25 26 /***************************************************************************** 27 * ddekit_sem_init * 28 *************************+**************************************************/ 29 ddekit_sem_t *ddekit_sem_init(int value) 30 { 31 ddekit_sem_t *sem; 32 33 sem = (ddekit_sem_t *) ddekit_simple_malloc(sizeof(ddekit_sem_t)); 34 35 sem->count = value; 36 sem->wait_queue = NULL; 37 38 SEM_DEBUG(p); 39 return sem; 40 } 41 42 /***************************************************************************** 43 * ddekit_sem_deinit * 44 ****************************************************************************/ 45 void ddekit_sem_deinit(ddekit_sem_t *sem) 46 { 47 SEM_DEBUG(p); 48 ddekit_simple_free(sem); 49 } 50 51 /***************************************************************************** 52 * ddekit_sem_down * 53 ****************************************************************************/ 54 void ddekit_sem_down(ddekit_sem_t *sem) 55 { 56 SEM_DEBUG(p); 57 if(sem->count == 0) { 58 if(sem->wait_queue == NULL) { 59 sem->wait_queue = ddekit_thread_myself(); 60 } else { 61 ddekit_thread_t *pos = sem->wait_queue; 62 while(pos->next != NULL) { 63 pos = pos->next; 64 } 65 pos->next = ddekit_thread_myself(); 66 } 67 _ddekit_thread_schedule(); 68 } else { 69 sem->count--; 70 } 71 } 72 73 /***************************************************************************** 74 * ddekit_sem_down_try * 75 ****************************************************************************/ 76 int ddekit_sem_down_try(ddekit_sem_t *sem) 77 { 78 if(sem->count == 0) { 79 return -1; 80 } 81 sem->count--; 82 return 0; 83 } 84 85 /***************************************************************************** 86 * ddekit_sem_up * 87 ****************************************************************************/ 88 void ddekit_sem_up(ddekit_sem_t *sem) 89 { 90 SEM_DEBUG(p); 91 if (sem->wait_queue == NULL) { 92 sem->count++; 93 return; 94 } else { 95 ddekit_thread_t *waiter = sem->wait_queue; 96 sem->wait_queue = waiter->next; 97 waiter->next = NULL; 98 _ddekit_thread_enqueue(waiter); 99 ddekit_thread_schedule(); 100 } 101 } 102 103 /**************************************************************************** 104 * ddekit_sem_down_timed * 105 ***************************************************************************/ 106 int ddekit_sem_down_timed(ddekit_sem_t *sem, int timo ) 107 { 108 ddekit_panic("not implemented!"); 109 return 0; 110 } 111 112