Allow max_events to be zero in mtdev_pull()

When reading from non-blocking devices, it makes sense to read
all events available. This patch lets a zero max_events achieve that.

Signed-off-by: Henrik Rydberg <rydberg@euromail.se>

2 files changed, 7 insertions, 4 deletions

diff --git a/include/mtdev.h b/include/mtdev.h
index abb76da..7d442f1 100644
--- a/include/mtdev.h
+++ b/include/mtdev.h
@@ -189,12 +189,13 @@ void mtdev_put(struct mtdev *dev, const struct input_event *ev);
  * mtdev_pull - pull events from the kernel device
  * @dev: the mtdev in use
  * @fd: file descriptor of the kernel device
- * @max_events: max number of events to read
+ * @max_events: max number of events to read (zero for all)
  *
  * Read a maxmimum of max_events events from the device, and put them
- * in the converter. The read operation behaves as dictated by the
- * file descriptior; if O_NONBLOCK is not set, the read will block
- * until max_events events are available or the buffer is full.
+ * in the converter. If max_events is zero, all available events will
+ * be read. The read operation behaves as dictated by the file
+ * descriptior; if O_NONBLOCK is not set, the read will block until
+ * max_events events are available or the buffer is full.
  *
  * On success, returns the number of events read. Otherwise, a standard
  * negative error number is returned.
diff --git a/src/iobuf.c b/src/iobuf.c
index 199e0d8..6516a2c 100644
--- a/src/iobuf.c
+++ b/src/iobuf.c
@@ -68,6 +68,8 @@ int mtdev_pull(struct mtdev *dev, int fd, int max_events)
 	struct mtdev_state *state = dev->state;
 	struct input_event ev;
 	int ret, count = 0;
+	if (max_events <= 0)
+		max_events = DIM_EVENTS;
 	while (max_events-- && !evbuf_full(&state->inbuf)) {
 		ret = mtdev_fetch(dev, fd, &ev);
 		if (ret < 0)