Umut Aradağ
/
Semaphores
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Revision 3:cf23d5c2ef90, committed 2011-08-06
- Comitter:
- umutaradag
- Date:
- Sat Aug 06 04:40:56 2011 +0000
- Parent:
- 2:ac3746d21033
- Commit message:
Changed in this revision
| semaphore.c | Show annotated file Show diff for this revision Revisions of this file |
| semaphore.h | Show annotated file Show diff for this revision Revisions of this file |
--- a/semaphore.c Thu Aug 04 10:00:02 2011 +0000
+++ b/semaphore.c Sat Aug 06 04:40:56 2011 +0000
@@ -4,32 +4,34 @@
void semInit(semaphore* s, int initVal)
{
- *s = initVal;
+ s->count = initVal;
}
void semPost(semaphore* s)
{
__disable_irq();
- (*s)++;
+ s->count++;
//printf("sem released %d\n",*s);
__enable_irq();
}
-int semPend(semaphore* s, int trials)
+int semPend(semaphore* s, int maxNumOfTrials)
{
- int* counter = (int*)malloc(sizeof(int));
+ s->trials = 0;
do
{
__disable_irq();
//printf("sem testing %d\n",*s);
- if(*s>0)
+ if(s->count > 0)
{
- (*s)--;
+ s->count--;
__enable_irq();
//printf("sem acquired\n");
- free(counter);
return SEM_OK;
}
__enable_irq();
- }while(trials > (*counter)++);
- free(counter);
+ }while(maxNumOfTrials > s->trials++);
return SEM_ERR;
+}
+void semSet(semaphore* s, int val)
+{
+ s->count = val;
}
\ No newline at end of file
--- a/semaphore.h Thu Aug 04 10:00:02 2011 +0000
+++ b/semaphore.h Sat Aug 06 04:40:56 2011 +0000
@@ -1,9 +1,15 @@
-typedef int semaphore;
+typedef struct
+{
+ int count;
+ int trials;
+}
+semaphore;
#define SEM_OK 1
#define SEM_ERR 0
void semInit(semaphore* s, int initVal);
void semPost(semaphore* s);
+void semSet(semaphore* s, int val);
int semPend(semaphore* s, int trials);
\ No newline at end of file