Initial commit

Change-Id: I6a4444e3c193dae437cd7929f4c39aba7b749efa
diff --git a/libfdproto/fifo.c b/libfdproto/fifo.c
new file mode 100644
index 0000000..cf5b7fc
--- /dev/null
+++ b/libfdproto/fifo.c
@@ -0,0 +1,700 @@
+/*********************************************************************************************************
+* Software License Agreement (BSD License)                                                               *
+* Author: Sebastien Decugis <sdecugis@freediameter.net>							 *
+*													 *
+* Copyright (c) 2013, WIDE Project and NICT								 *
+* All rights reserved.											 *
+* 													 *
+* Redistribution and use of this software in source and binary forms, with or without modification, are  *
+* permitted provided that the following conditions are met:						 *
+* 													 *
+* * Redistributions of source code must retain the above 						 *
+*   copyright notice, this list of conditions and the 							 *
+*   following disclaimer.										 *
+*    													 *
+* * Redistributions in binary form must reproduce the above 						 *
+*   copyright notice, this list of conditions and the 							 *
+*   following disclaimer in the documentation and/or other						 *
+*   materials provided with the distribution.								 *
+* 													 *
+* * Neither the name of the WIDE Project or NICT nor the 						 *
+*   names of its contributors may be used to endorse or 						 *
+*   promote products derived from this software without 						 *
+*   specific prior written permission of WIDE Project and 						 *
+*   NICT.												 *
+* 													 *
+* THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS" AND ANY EXPRESS OR IMPLIED *
+* WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A *
+* PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE LIABLE FOR *
+* ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT 	 *
+* LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS 	 *
+* INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR *
+* TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF   *
+* ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.								 *
+*********************************************************************************************************/
+
+/* FIFO queues module.
+ *
+ * The threads that call these functions must be in the cancellation state PTHREAD_CANCEL_ENABLE and type PTHREAD_CANCEL_DEFERRED.
+ * This is the default state and type on thread creation.
+ *
+ * In order to destroy properly a queue, the application must:
+ *  -> shutdown any process that can add into the queue first.
+ *  -> pthread_cancel any thread that could be waiting on the queue.
+ *  -> consume any element that is in the queue, using fd_qu_tryget_int.
+ *  -> then destroy the queue using fd_mq_del.
+ */
+
+#include "fdproto-internal.h"
+
+/* Definition of a FIFO queue object */
+struct fifo {
+	int		eyec;	/* An eye catcher, also used to check a queue is valid. FIFO_EYEC */
+	
+	pthread_mutex_t	mtx;	/* Mutex protecting this queue */
+	pthread_cond_t	cond_pull;	/* condition variable for pulling threads */
+	pthread_cond_t	cond_push;	/* condition variable for pushing threads */
+	
+	struct fd_list	list;	/* sentinel for the list of elements */
+	int		count;	/* number of objects in the list */
+	int		thrs;	/* number of threads waiting for a new element (when count is 0) */
+	
+	int 		max;	/* maximum number of items to accept if not 0 */
+	int		thrs_push; /* number of threads waitnig to push an item */
+	
+	uint16_t	high;	/* High level threshold (see libfreeDiameter.h for details) */
+	uint16_t	low;	/* Low level threshhold */
+	void 		*data;	/* Opaque pointer for threshold callbacks */
+	void		(*h_cb)(struct fifo *, void **); /* The callbacks */
+	void		(*l_cb)(struct fifo *, void **);
+	int 		highest;/* The highest count value for which h_cb has been called */
+	int		highest_ever; /* The max count value this queue has reached (for tweaking) */
+	
+	long long	total_items;   /* Cumulated number of items that went through this fifo (excluding current count), always increasing. */
+	struct timespec total_time;    /* Cumulated time all items spent in this queue, including blocking time (always growing, use deltas for monitoring) */
+	struct timespec blocking_time; /* Cumulated time threads trying to post new items were blocked (queue full). */
+	struct timespec last_time;     /* For the last element retrieved from the queue, how long it take between posting (including blocking) and poping */
+	
+};
+
+struct fifo_item {
+	struct fd_list   item;
+	struct timespec  posted_on;
+};
+
+/* The eye catcher value */
+#define FIFO_EYEC	0xe7ec1130
+
+/* Macro to check a pointer */
+#define CHECK_FIFO( _queue ) (( (_queue) != NULL) && ( (_queue)->eyec == FIFO_EYEC) )
+
+
+/* Create a new queue, with max number of items -- use 0 for no max */
+int fd_fifo_new ( struct fifo ** queue, int max )
+{
+	struct fifo * new;
+	
+	TRACE_ENTRY( "%p", queue );
+	
+	CHECK_PARAMS( queue );
+	
+	/* Create a new object */
+	CHECK_MALLOC( new = malloc (sizeof (struct fifo) )  );
+	
+	/* Initialize the content */
+	memset(new, 0, sizeof(struct fifo));
+	
+	new->eyec = FIFO_EYEC;
+	CHECK_POSIX( pthread_mutex_init(&new->mtx, NULL) );
+	CHECK_POSIX( pthread_cond_init(&new->cond_pull, NULL) );
+	CHECK_POSIX( pthread_cond_init(&new->cond_push, NULL) );
+	new->max = max;
+	
+	fd_list_init(&new->list, NULL);
+	
+	/* We're done */
+	*queue = new;
+	return 0;
+}
+
+/* Dump the content of a queue */
+DECLARE_FD_DUMP_PROTOTYPE(fd_fifo_dump, char * name, struct fifo * queue, fd_fifo_dump_item_cb dump_item)
+{
+	FD_DUMP_HANDLE_OFFSET();
+	
+	if (name) {
+		CHECK_MALLOC_DO( fd_dump_extend( FD_DUMP_STD_PARAMS, "'%s'(@%p): ", name, queue), return NULL);	
+	} else {
+		CHECK_MALLOC_DO( fd_dump_extend( FD_DUMP_STD_PARAMS, "{fifo}(@%p): ", queue), return NULL);
+	}
+	
+	if (!CHECK_FIFO( queue )) {
+		return fd_dump_extend(FD_DUMP_STD_PARAMS, "INVALID/NULL");
+	}
+	
+	CHECK_POSIX_DO(  pthread_mutex_lock( &queue->mtx ), /* continue */  );
+	CHECK_MALLOC_DO( fd_dump_extend( FD_DUMP_STD_PARAMS, "items:%d,%d,%d threads:%d,%d stats:%lld/%ld.%06ld,%ld.%06ld,%ld.%06ld thresholds:%d,%d,%d,%p,%p,%p", 
+						queue->count, queue->highest_ever, queue->max,
+						queue->thrs, queue->thrs_push,
+						queue->total_items,(long)queue->total_time.tv_sec,(long)(queue->total_time.tv_nsec/1000),(long)queue->blocking_time.tv_sec,(long)(queue->blocking_time.tv_nsec/1000),(long)queue->last_time.tv_sec,(long)(queue->last_time.tv_nsec/1000),
+						queue->high, queue->low, queue->highest, queue->h_cb, queue->l_cb, queue->data), 
+			 goto error);
+	
+	if (dump_item) {
+		struct fd_list * li;
+		int i = 0;
+		for (li = queue->list.next; li != &queue->list; li = li->next) {
+			struct fifo_item * fi = (struct fifo_item *)li;
+			CHECK_MALLOC_DO( fd_dump_extend( FD_DUMP_STD_PARAMS, "\n [#%i](@%p)@%ld.%06ld: ", 
+						i++, fi->item.o, (long)fi->posted_on.tv_sec,(long)(fi->posted_on.tv_nsec/1000)), 
+					 goto error);
+			CHECK_MALLOC_DO( (*dump_item)(FD_DUMP_STD_PARAMS, fi->item.o), goto error);
+		}
+	}
+	CHECK_POSIX_DO(  pthread_mutex_unlock( &queue->mtx ), /* continue */  );
+	
+	return *buf;
+error:
+	CHECK_POSIX_DO(  pthread_mutex_unlock( &queue->mtx ), /* continue */  );
+	return NULL;
+}
+
+/* Delete a queue. It must be empty. */ 
+int fd_fifo_del ( struct fifo  ** queue )
+{
+	struct fifo * q;
+	int loops = 0;
+	
+	TRACE_ENTRY( "%p", queue );
+
+	CHECK_PARAMS( queue && CHECK_FIFO( *queue ) );
+	
+	q = *queue;
+	
+	CHECK_POSIX(  pthread_mutex_lock( &q->mtx )  );
+	
+	if ((q->count != 0) || (q->data != NULL)) {
+		TRACE_DEBUG(INFO, "The queue cannot be destroyed (%d, %p)", q->count, q->data);
+		CHECK_POSIX_DO(  pthread_mutex_unlock( &q->mtx ), /* no fallback */  );
+		return EINVAL;
+	}
+	
+	/* Ok, now invalidate the queue */
+	q->eyec = 0xdead;
+	
+	/* Have all waiting threads return an error */
+	while (q->thrs) {
+		CHECK_POSIX(  pthread_mutex_unlock( &q->mtx ));
+		CHECK_POSIX(  pthread_cond_signal(&q->cond_pull)  );
+		usleep(1000);
+		
+		CHECK_POSIX(  pthread_mutex_lock( &q->mtx )  );
+		ASSERT( ++loops < 20 ); /* detect infinite loops */
+	}
+	
+	/* sanity check */
+	ASSERT(FD_IS_LIST_EMPTY(&q->list));
+	
+	/* And destroy it */
+	CHECK_POSIX(  pthread_mutex_unlock( &q->mtx )  );
+	
+	CHECK_POSIX_DO(  pthread_cond_destroy( &q->cond_pull ),  );
+	
+	CHECK_POSIX_DO(  pthread_cond_destroy( &q->cond_push ),  );
+	
+	CHECK_POSIX_DO(  pthread_mutex_destroy( &q->mtx ),  );
+	
+	free(q);
+	*queue = NULL;
+	
+	return 0;
+}
+
+/* Move the content of old into new, and update loc_update atomically. We leave the old queue empty but valid */
+int fd_fifo_move ( struct fifo * old, struct fifo * new, struct fifo ** loc_update )
+{
+	int loops = 0;
+	
+	TRACE_ENTRY("%p %p %p", old, new, loc_update);
+	CHECK_PARAMS( CHECK_FIFO( old ) && CHECK_FIFO( new ));
+	
+	CHECK_PARAMS( ! old->data );
+	if (new->high) {
+		TODO("Implement support for thresholds in fd_fifo_move...");
+	}
+	
+	/* Update loc_update */
+	if (loc_update)
+		*loc_update = new;
+	
+	/* Lock the queues */
+	CHECK_POSIX(  pthread_mutex_lock( &old->mtx )  );
+	
+	CHECK_PARAMS_DO( (! old->thrs_push), {
+			pthread_mutex_unlock( &old->mtx );
+			return EINVAL;
+		} );
+	
+	CHECK_POSIX(  pthread_mutex_lock( &new->mtx )  );
+	
+	/* Any waiting thread on the old queue returns an error */
+	old->eyec = 0xdead;
+	while (old->thrs) {
+		CHECK_POSIX(  pthread_mutex_unlock( &old->mtx ));
+		CHECK_POSIX(  pthread_cond_signal( &old->cond_pull )  );
+		usleep(1000);
+		
+		CHECK_POSIX(  pthread_mutex_lock( &old->mtx )  );
+		ASSERT( loops < 20 ); /* detect infinite loops */
+	}
+	
+	/* Move all data from old to new */
+	fd_list_move_end( &new->list, &old->list );
+	if (old->count && (!new->count)) {
+		CHECK_POSIX(  pthread_cond_signal(&new->cond_pull)  );
+	}
+	new->count += old->count;
+	
+	/* Reset old */
+	old->count = 0;
+	old->eyec = FIFO_EYEC;
+	
+	/* Merge the stats in the new queue */
+	new->total_items += old->total_items;
+	old->total_items = 0;
+	
+	new->total_time.tv_nsec += old->total_time.tv_nsec;
+	new->total_time.tv_sec += old->total_time.tv_sec + (new->total_time.tv_nsec / 1000000000);
+	new->total_time.tv_nsec %= 1000000000;
+	old->total_time.tv_nsec = 0;
+	old->total_time.tv_sec = 0;
+	
+	new->blocking_time.tv_nsec += old->blocking_time.tv_nsec;
+	new->blocking_time.tv_sec += old->blocking_time.tv_sec + (new->blocking_time.tv_nsec / 1000000000);
+	new->blocking_time.tv_nsec %= 1000000000;
+	old->blocking_time.tv_nsec = 0;
+	old->blocking_time.tv_sec = 0;
+	
+	/* Unlock, we're done */
+	CHECK_POSIX(  pthread_mutex_unlock( &new->mtx )  );
+	CHECK_POSIX(  pthread_mutex_unlock( &old->mtx )  );
+	
+	return 0;
+}
+
+/* Get the information on the queue */
+int fd_fifo_getstats( struct fifo * queue, int * current_count, int * limit_count, int * highest_count, long long * total_count, 
+				           struct timespec * total, struct timespec * blocking, struct timespec * last)
+{
+	TRACE_ENTRY( "%p %p %p %p %p %p %p %p", queue, current_count, limit_count, highest_count, total_count, total, blocking, last);
+	
+	/* Check the parameters */
+	CHECK_PARAMS( CHECK_FIFO( queue ) );
+	
+	/* lock the queue */
+	CHECK_POSIX(  pthread_mutex_lock( &queue->mtx )  );
+	
+	if (current_count)
+		*current_count = queue->count;
+	
+	if (limit_count)
+		*limit_count = queue->max;
+	
+	if (highest_count)
+		*highest_count = queue->highest_ever;
+	
+	if (total_count)
+		*total_count = queue->total_items;
+	
+	if (total)
+		memcpy(total, &queue->total_time, sizeof(struct timespec));
+	
+	if (blocking)
+		memcpy(blocking, &queue->blocking_time, sizeof(struct timespec));
+	
+	if (last)
+		memcpy(last, &queue->last_time, sizeof(struct timespec));
+	
+	/* Unlock */
+	CHECK_POSIX(  pthread_mutex_unlock( &queue->mtx )  );
+	
+	/* Done */
+	return 0;
+}
+
+
+/* alternate version with no error checking */
+int fd_fifo_length ( struct fifo * queue )
+{
+	if ( !CHECK_FIFO( queue ) )
+		return 0;
+	
+	return queue->count; /* Let's hope it's read atomically, since we are not locking... */
+}
+
+/* Set the thresholds of the queue */
+int fd_fifo_setthrhd ( struct fifo * queue, void * data, uint16_t high, void (*h_cb)(struct fifo *, void **), uint16_t low, void (*l_cb)(struct fifo *, void **) )
+{
+	TRACE_ENTRY( "%p %p %hu %p %hu %p", queue, data, high, h_cb, low, l_cb );
+	
+	/* Check the parameters */
+	CHECK_PARAMS( CHECK_FIFO( queue ) && (high > low) && (queue->data == NULL) );
+	
+	/* lock the queue */
+	CHECK_POSIX(  pthread_mutex_lock( &queue->mtx )  );
+	
+	/* Save the values */
+	queue->high = high;
+	queue->low  = low;
+	queue->data = data;
+	queue->h_cb = h_cb;
+	queue->l_cb = l_cb;
+	
+	/* Unlock */
+	CHECK_POSIX(  pthread_mutex_unlock( &queue->mtx )  );
+	
+	/* Done */
+	return 0;
+}
+
+
+/* This handler is called when a thread is blocked on a queue, and cancelled */
+static void fifo_cleanup_push(void * queue)
+{
+	struct fifo * q = (struct fifo *)queue;
+	TRACE_ENTRY( "%p", queue );
+	
+	/* The thread has been cancelled, therefore it does not wait on the queue anymore */
+	q->thrs_push--;
+	
+	/* Now unlock the queue, and we're done */
+	CHECK_POSIX_DO(  pthread_mutex_unlock( &q->mtx ),  /* nothing */  );
+	
+	/* End of cleanup handler */
+	return;
+}
+
+
+/* Post a new item in the queue */
+int fd_fifo_post_internal ( struct fifo * queue, void ** item, int skip_max )
+{
+	struct fifo_item * new;
+	int call_cb = 0;
+	struct timespec posted_on, queued_on;
+	
+	/* Get the timing of this call */
+	CHECK_SYS(  clock_gettime(CLOCK_REALTIME, &posted_on)  );
+	
+	/* lock the queue */
+	CHECK_POSIX(  pthread_mutex_lock( &queue->mtx )  );
+	
+	if ((!skip_max) && (queue->max)) {
+		while (queue->count >= queue->max) {
+			int ret = 0;
+			
+			/* We have to wait for an item to be pulled */
+			queue->thrs_push++ ;
+			pthread_cleanup_push( fifo_cleanup_push, queue);
+			ret = pthread_cond_wait( &queue->cond_push, &queue->mtx );
+			pthread_cleanup_pop(0);
+			queue->thrs_push-- ;
+			
+			ASSERT( ret == 0 );
+		}
+	}
+	
+	/* Create a new list item */
+	CHECK_MALLOC_DO(  new = malloc (sizeof (struct fifo_item)) , {
+			pthread_mutex_unlock( &queue->mtx );
+			return ENOMEM;
+		} );
+	
+	fd_list_init(&new->item, *item);
+	*item = NULL;
+	
+	/* Add the new item at the end */
+	fd_list_insert_before( &queue->list, &new->item);
+	queue->count++;
+	if (queue->highest_ever < queue->count)
+		queue->highest_ever = queue->count;
+	if (queue->high && ((queue->count % queue->high) == 0)) {
+		call_cb = 1;
+		queue->highest = queue->count;
+	}
+	
+	/* store timing */
+	memcpy(&new->posted_on, &posted_on, sizeof(struct timespec));
+	
+	/* update queue timing info "blocking time" */
+	{
+		long long blocked_ns;
+		CHECK_SYS(  clock_gettime(CLOCK_REALTIME, &queued_on)  );
+		blocked_ns = (queued_on.tv_sec - posted_on.tv_sec) * 1000000000;
+		blocked_ns += (queued_on.tv_nsec - posted_on.tv_nsec);
+		blocked_ns += queue->blocking_time.tv_nsec;
+		queue->blocking_time.tv_sec += blocked_ns / 1000000000;
+		queue->blocking_time.tv_nsec = blocked_ns % 1000000000;
+	}
+	
+	/* Signal if threads are asleep */
+	if (queue->thrs > 0) {
+		CHECK_POSIX(  pthread_cond_signal(&queue->cond_pull)  );
+	}
+	if (queue->thrs_push > 0) {
+		/* cascade */
+		CHECK_POSIX(  pthread_cond_signal(&queue->cond_push)  );
+	}
+	
+	/* Unlock */
+	CHECK_POSIX(  pthread_mutex_unlock( &queue->mtx )  );
+	
+	/* Call high-watermark cb as needed */
+	if (call_cb && queue->h_cb)
+		(*queue->h_cb)(queue, &queue->data);
+	
+	/* Done */
+	return 0;
+}
+
+/* Post a new item in the queue */
+int fd_fifo_post_int ( struct fifo * queue, void ** item )
+{
+	TRACE_ENTRY( "%p %p", queue, item );
+	
+	/* Check the parameters */
+	CHECK_PARAMS( CHECK_FIFO( queue ) && item && *item );
+	
+	return fd_fifo_post_internal ( queue,item, 0 );
+	
+}
+
+/* Post a new item in the queue, not blocking */
+int fd_fifo_post_noblock ( struct fifo * queue, void ** item )
+{
+	TRACE_ENTRY( "%p %p", queue, item );
+	
+	/* Check the parameters */
+	CHECK_PARAMS( CHECK_FIFO( queue ) && item && *item );
+	
+	return fd_fifo_post_internal ( queue,item, 1 );
+	
+}
+
+/* Pop the first item from the queue */
+static void * mq_pop(struct fifo * queue)
+{
+	void * ret = NULL;
+	struct fifo_item * fi;
+	struct timespec now;
+	
+	ASSERT( ! FD_IS_LIST_EMPTY(&queue->list) );
+	
+	fi = (struct fifo_item *)(queue->list.next);
+	ret = fi->item.o;
+	fd_list_unlink(&fi->item);
+	queue->count--;
+	queue->total_items++;
+	
+	/* Update the timings */
+	CHECK_SYS_DO(  clock_gettime(CLOCK_REALTIME, &now), goto skip_timing  );
+	{
+		long long elapsed = (now.tv_sec - fi->posted_on.tv_sec) * 1000000000;
+		elapsed += now.tv_nsec - fi->posted_on.tv_nsec;
+		
+		queue->last_time.tv_sec = elapsed / 1000000000;
+		queue->last_time.tv_nsec = elapsed % 1000000000;
+		
+		elapsed += queue->total_time.tv_nsec;
+		queue->total_time.tv_sec += elapsed / 1000000000;
+		queue->total_time.tv_nsec = elapsed % 1000000000;
+	}
+skip_timing:	
+	free(fi);
+	
+	if (queue->thrs_push) {
+		CHECK_POSIX_DO( pthread_cond_signal( &queue->cond_push ), );
+	}
+	
+	return ret;
+}
+
+/* Check if the low watermark callback must be called. */
+static __inline__ int test_l_cb(struct fifo * queue)
+{
+	if ((queue->high == 0) || (queue->low == 0) || (queue->l_cb == 0))
+		return 0;
+	
+	if (((queue->count % queue->high) == queue->low) && (queue->highest > queue->count)) {
+		queue->highest -= queue->high;
+		return 1;
+	}
+	
+	return 0;
+}
+
+/* Try poping an item */
+int fd_fifo_tryget_int ( struct fifo * queue, void ** item )
+{
+	int wouldblock = 0;
+	int call_cb = 0;
+	
+	TRACE_ENTRY( "%p %p", queue, item );
+	
+	/* Check the parameters */
+	CHECK_PARAMS( CHECK_FIFO( queue ) && item );
+	
+	/* lock the queue */
+	CHECK_POSIX(  pthread_mutex_lock( &queue->mtx )  );
+	
+	/* Check queue status */
+	if (queue->count > 0) {
+got_item:
+		/* There are elements in the queue, so pick the first one */
+		*item = mq_pop(queue);
+		call_cb = test_l_cb(queue);
+	} else {
+		if (queue->thrs_push > 0) {
+			/* A thread is trying to push something, let's give it a chance */
+			CHECK_POSIX(  pthread_mutex_unlock( &queue->mtx )  );
+			CHECK_POSIX(  pthread_cond_signal( &queue->cond_push )  );
+			usleep(1000);
+			CHECK_POSIX(  pthread_mutex_lock( &queue->mtx )  );
+			if (queue->count > 0)
+				goto got_item;
+		}
+		
+		wouldblock = 1;
+		*item = NULL;
+	}
+		
+	/* Unlock */
+	CHECK_POSIX(  pthread_mutex_unlock( &queue->mtx )  );
+	
+	/* Call low watermark callback as needed */
+	if (call_cb)
+		(*queue->l_cb)(queue, &queue->data);
+	
+	/* Done */
+	return wouldblock ? EWOULDBLOCK : 0;
+}
+
+/* This handler is called when a thread is blocked on a queue, and cancelled */
+static void fifo_cleanup(void * queue)
+{
+	struct fifo * q = (struct fifo *)queue;
+	TRACE_ENTRY( "%p", queue );
+	
+	/* The thread has been cancelled, therefore it does not wait on the queue anymore */
+	q->thrs--;
+	
+	/* Now unlock the queue, and we're done */
+	CHECK_POSIX_DO(  pthread_mutex_unlock( &q->mtx ),  /* nothing */  );
+	
+	/* End of cleanup handler */
+	return;
+}
+
+/* The internal function for fd_fifo_timedget and fd_fifo_get */
+static int fifo_tget ( struct fifo * queue, void ** item, int istimed, const struct timespec *abstime)
+{
+	int call_cb = 0;
+	int ret = 0;
+	
+	/* Check the parameters */
+	CHECK_PARAMS( CHECK_FIFO( queue ) && item && (abstime || !istimed) );
+	
+	/* Initialize the return value */
+	*item = NULL;
+	
+	/* lock the queue */
+	CHECK_POSIX(  pthread_mutex_lock( &queue->mtx )  );
+	
+awaken:
+	/* Check queue status */
+	if (!CHECK_FIFO( queue )) {
+		/* The queue is being destroyed */
+		CHECK_POSIX(  pthread_mutex_unlock( &queue->mtx )  );
+		TRACE_DEBUG(FULL, "The queue is being destroyed -> EPIPE");
+		return EPIPE;
+	}
+	
+	if (queue->count > 0) {
+		/* There are items in the queue, so pick the first one */
+		*item = mq_pop(queue);
+		call_cb = test_l_cb(queue);
+	} else {
+		/* We have to wait for a new item */
+		queue->thrs++ ;
+		pthread_cleanup_push( fifo_cleanup, queue);
+		if (istimed) {
+			ret = pthread_cond_timedwait( &queue->cond_pull, &queue->mtx, abstime );
+		} else {
+			ret = pthread_cond_wait( &queue->cond_pull, &queue->mtx );
+		}
+		pthread_cleanup_pop(0);
+		queue->thrs-- ;
+		if (ret == 0)
+			goto awaken;  /* test for spurious wake-ups */
+		
+		/* otherwise (ETIMEDOUT / other error) just continue */
+	}
+	
+	/* Unlock */
+	CHECK_POSIX(  pthread_mutex_unlock( &queue->mtx )  );
+	
+	/* Call low watermark callback as needed */
+	if (call_cb)
+		(*queue->l_cb)(queue, &queue->data);
+	
+	/* Done */
+	return ret;
+}
+
+/* Get the next available item, block until there is one */
+int fd_fifo_get_int ( struct fifo * queue, void ** item )
+{
+	TRACE_ENTRY( "%p %p", queue, item );
+	return fifo_tget(queue, item, 0, NULL);
+}
+
+/* Get the next available item, block until there is one, or the timeout expires */
+int fd_fifo_timedget_int ( struct fifo * queue, void ** item, const struct timespec *abstime )
+{
+	TRACE_ENTRY( "%p %p %p", queue, item, abstime );
+	return fifo_tget(queue, item, 1, abstime);
+}
+
+/* Test if data is available in the queue, without pulling it */
+int fd_fifo_select ( struct fifo * queue, const struct timespec *abstime )
+{
+	int ret = 0;
+	TRACE_ENTRY( "%p %p", queue, abstime );
+	
+	CHECK_PARAMS_DO( CHECK_FIFO( queue ), return -EINVAL );
+	
+	/* lock the queue */
+	CHECK_POSIX_DO(  pthread_mutex_lock( &queue->mtx ), return -__ret__  );
+	
+awaken:	
+	ret = (queue->count > 0 ) ? queue->count : 0;
+	if ((ret == 0) && (abstime != NULL)) {
+		/* We have to wait for a new item */
+		queue->thrs++ ;
+		pthread_cleanup_push( fifo_cleanup, queue);
+		ret = pthread_cond_timedwait( &queue->cond_pull, &queue->mtx, abstime );
+		pthread_cleanup_pop(0);
+		queue->thrs-- ;
+		if (ret == 0)
+			goto awaken;  /* test for spurious wake-ups */
+		
+		if (ret == ETIMEDOUT)
+			ret = 0;
+		else 
+			ret = -ret;
+	}
+	
+	/* Unlock */
+	CHECK_POSIX_DO(  pthread_mutex_unlock( &queue->mtx ), return -__ret__  );
+	
+	return ret;
+}