/*
* Function: FetchWork
*
* Fetch a work item from the queue, blocking if none available.
* Return value indicates of false indicates error/fatal condition.
*/
BOOL
FetchWork ( WorkQueue* pq, void** ppw )
{
DWORD rc;
if (!pq) {
queue_error("FetchWork", "NULL WorkQueue object");
return false;
}
if (!ppw) {
queue_error("FetchWork", "NULL WorkItem object");
return false;
}
EnterCriticalSection(&pq->queueLock);
*ppw = pq->items[pq->head];
/* For sanity's sake, zero out the pointer. */
pq->items[pq->head] = NULL;
pq->head = (pq->head + 1) % WORKQUEUE_SIZE;
rc = ReleaseSemaphore(pq->roomAvailable,1, NULL);
LeaveCriticalSection(&pq->queueLock);
if ( 0 == rc ) {
queue_error_rc("FetchWork.ReleaseSemaphore()", GetLastError());
return false;
}
return true;
}
/*
* Function: SubmitWork
*
* Add work item to the queue, blocking if no room available.
* Return value indicates of false indicates error/fatal condition.
*/
BOOL
SubmitWork ( WorkQueue* pq, void* pw )
{
DWORD rc;
if (!pq) {
queue_error("SubmitWork", "NULL WorkQueue object");
return false;
}
if (!pw) {
queue_error("SubmitWork", "NULL WorkItem object");
return false;
}
/* Block waiting for work item to become available */
if ( (rc = WaitForSingleObject( pq->roomAvailable, INFINITE))
!= WAIT_OBJECT_0 ) {
queue_error_rc("SubmitWork.WaitForSingleObject(workAvailable)",
( (WAIT_FAILED == rc) ? GetLastError() : rc));
return false;
}
EnterCriticalSection(&pq->queueLock);
pq->items[pq->tail] = pw;
pq->tail = (pq->tail + 1) % WORKQUEUE_SIZE;
rc = ReleaseSemaphore(pq->workAvailable,1, NULL);
LeaveCriticalSection(&pq->queueLock);
if ( 0 == rc ) {
queue_error_rc("SubmitWork.ReleaseSemaphore()", GetLastError());
return false;
}
return true;
}
static void add_error_log_rec
(
error_log_rec_t *log_rec_p,
STRTAB_str_t filename,
int lineno,
idl_error_list_t *msgs
)
{
if (log_rec_p->lineno < lineno)
{
if (log_rec_p->links.asBinTree.right != NULL)
add_error_log_rec(log_rec_p->links.asBinTree.right, filename, lineno,
msgs);
else
log_rec_p->links.asBinTree.right = alloc_log_rec(filename, lineno,
msgs);
return;
}
if (log_rec_p->lineno > lineno)
{
if (log_rec_p->links.asBinTree.left != NULL)
add_error_log_rec(log_rec_p->links.asBinTree.left, filename, lineno,
msgs);
else
log_rec_p->links.asBinTree.left = alloc_log_rec(filename, lineno,
msgs);
return;
}
if (log_rec_p->lineno == lineno)
queue_error(log_rec_p, filename, msgs);
}
/*
* Function: NewWorkQueue
*
* The queue constructor - semaphores are initialised to match
* max number of queue entries.
*
*/
WorkQueue*
NewWorkQueue()
{
WorkQueue* wq = (WorkQueue*)malloc(sizeof(WorkQueue));
if (!wq) {
queue_error("NewWorkQueue", "malloc() failed");
return wq;
}
memset(wq, 0, sizeof *wq);
InitializeCriticalSection(&wq->queueLock);
wq->workAvailable = newSemaphore(0, WORKQUEUE_SIZE);
wq->roomAvailable = newSemaphore(WORKQUEUE_SIZE, WORKQUEUE_SIZE);
/* Fail if we were unable to create any of the sync objects. */
if ( NULL == wq->workAvailable ||
NULL == wq->roomAvailable ) {
FreeWorkQueue(wq);
return NULL;
}
return wq;
}
/*
* Function: GetWork
*
* Fetch a work item from the queue, blocking if none available.
* Return value indicates of false indicates error/fatal condition.
*/
BOOL
GetWork ( WorkQueue* pq, void** ppw )
{
DWORD rc;
if (!pq) {
queue_error("GetWork", "NULL WorkQueue object");
return false;
}
if (!ppw) {
queue_error("GetWork", "NULL WorkItem object");
return false;
}
/* Block waiting for work item to become available */
if ( (rc = WaitForSingleObject( pq->workAvailable, INFINITE))
!= WAIT_OBJECT_0 ) {
queue_error_rc("GetWork.WaitForSingleObject(workAvailable)",
( (WAIT_FAILED == rc) ? GetLastError() : rc));
return false;
}
return FetchWork(pq,ppw);
}
