X-Git-Url: https://git.kernel.dk/?p=fio.git;a=blobdiff_plain;f=fifo.c;h=ac0d21576dcf9fce5192945472cb7dd04f624bff;hp=1e55b6344ba1d4cbcb52dac65a6ddbb87d33a81d;hb=01bf5128d0581e267383f280c6a1dcd26517240f;hpb=e28875637094451a3c5ec4071f964c1a02dd8f5b

diff --git a/fifo.c b/fifo.c
index 1e55b634..ac0d2157 100644
--- a/fifo.c
+++ b/fifo.c
@@ -15,7 +15,7 @@
  *
  * You should have received a copy of the GNU General Public License
  * along with this program; if not, write to the Free Software
- * Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
+ * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.
  *
  */
 
@@ -24,6 +24,7 @@
 #include <string.h>
 
 #include "fifo.h"
+#include "minmax.h"
 
 struct fifo *fifo_alloc(unsigned int size)
 {
@@ -31,11 +32,11 @@ struct fifo *fifo_alloc(unsigned int size)
 
 	fifo = malloc(sizeof(struct fifo));
 	if (!fifo)
-		return 0;
+		return NULL;
 
 	fifo->buffer = malloc(size);
 	fifo->size = size;
-	fifo->in = fifo->out = 0xffff0000;
+	fifo->in = fifo->out = 0;
 
 	return fifo;
 }
@@ -50,7 +51,7 @@ unsigned int fifo_put(struct fifo *fifo, void *buffer, unsigned int len)
 {
 	unsigned int l;
 
-	len = min(len, fifo->size - fifo->in + fifo->out);
+	len = min(len, fifo_room(fifo));
 
 	/* first put the data starting from fifo->in to buffer end */
 	l = min(len, fifo->size - (fifo->in & (fifo->size - 1)));
@@ -69,20 +70,29 @@ unsigned int fifo_put(struct fifo *fifo, void *buffer, unsigned int len)
 	return len;
 }
 
-unsigned int fifo_get(struct fifo *fifo, void *buffer, unsigned int len)
+unsigned int fifo_get(struct fifo *fifo, void *buf, unsigned int len)
 {
-	unsigned int l;
-
 	len = min(len, fifo->in - fifo->out);
 
-	/* first get the data from fifo->out until the end of the buffer */
-	l = min(len, fifo->size - (fifo->out & (fifo->size - 1)));
-	memcpy(buffer, fifo->buffer + (fifo->out & (fifo->size - 1)), l);
+	if (buf) {
+		unsigned int l;
 
-	/* then get the rest (if any) from the beginning of the buffer */
-	memcpy(buffer + l, fifo->buffer, len - l);
+		/*
+		 * first get the data from fifo->out until the end of the buffer
+		 */
+		l = min(len, fifo->size - (fifo->out & (fifo->size - 1)));
+		memcpy(buf, fifo->buffer + (fifo->out & (fifo->size - 1)), l);
+
+		/*
+		 * then get the rest (if any) from the beginning of the buffer
+		 */
+		memcpy(buf + l, fifo->buffer, len - l);
+	}
 
 	fifo->out += len;
 
+	if (fifo->in == fifo->out)
+		fifo->in = fifo->out = 0;
+
 	return len;
 }