Remove dependency on libevdev (mostly complete) + minor fixes

Signed-off-by: Mattias Andrée <maandree@kth.se>

1 files changed, 107 insertions, 38 deletions

diff --git a/libgamepad_next_event.c b/libgamepad_next_event.c
index c74d641..b9d8986 100644
--- a/libgamepad_next_event.c
+++ b/libgamepad_next_event.c
@@ -2,56 +2,125 @@
 #include "common.h"
 
 
-int
-libgamepad_next_event(struct libgamepad_device *device, struct libgamepad_input_event *eventp)
+static int
+update_button(struct libgamepad_device *device, uint16_t code, int32_t value)
 {
-	int r;
-	struct input_event ev;
+	int16_t index;
+	if (code > ELEMSOF(device->button_map))
+		return 0;
+	index = device->button_map[code];
+	if (index < 0 || GETBIT(device->internals->buttons, (size_t)index) == value)
+		return 1;
+	XORBIT(device->internals->buttons, (size_t)index);
+	return 1;
+}
+
+
+static int
+update_absolute_axis(struct libgamepad_device *device, uint16_t code, int32_t value)
+{
+	int16_t index;
+	if (code > ELEMSOF(device->absolute_axis_map))
+		return 0;
+	index = device->absolute_axis_map[code];
+	if (index < 0 || device->internals->absinfo[index].value == value)
+		return 0;
+	device->internals->absinfo[index].value = value;
+	return 1;
+}
+
+
+ssize_t
+libgamepad_next_event(struct libgamepad_device *device, struct libgamepad_input_event *events, size_t max)
+{
+	size_t i, dequeued = 0;
+	void *new;
+	ssize_t r;
+	struct input_event *ev;
+
+	if (device->internals->deferred_error) {
+		errno = device->internals->deferred_error;
+		device->internals->deferred_error = 0;
+		return -1;
+	}
+
+	if (device->internals->require_sync)
+		if (libgamepad_drain_events(device))
+			return -1;
 
-	if (!device->internals->require_sync) {
-		r = libevdev_next_event(device->internals->dev, LIBEVDEV_READ_FLAG_NORMAL, &ev);
-		if (r < 0) {
-			errno = -r;
+	if (max > device->internals->evbuf_size) {
+		if (max > SIZE_MAX / sizeof(*device->internals->evbuf)) {
+			errno = ENOMEM;
 			return -1;
 		}
-	} else {
-		r = libevdev_next_event(device->internals->dev, LIBEVDEV_READ_FLAG_SYNC, &ev);
-		if (r == -EAGAIN) {
-			device->internals->require_sync = 0; /* yes, this is how it is document */
-			return 0;
-		} else if (r < 0) {
-			errno = -r;
+		new = realloc(device->internals->evbuf, max * sizeof(*device->internals->evbuf));
+		if (!new)
+			return -1;
+		device->internals->evbuf = new;
+		device->internals->evbuf_size = max;
+	}
+
+	dequeued = device->internals->ev_queued < max ? device->internals->ev_queued : max;
+	if (!dequeued || dequeued < max) {
+		r = read(device->fd, &device->internals->evbuf[dequeued], (max - dequeued) * sizeof(*device->internals->evbuf));
+		if (r <= 0) {
+			if (!r && (max - dequeued))
+				errno = ENODEV;
+			return -1;
+		} else if ((size_t)r % sizeof(*device->internals->evbuf)) {
+			errno = EBADF;
 			return -1;
 		}
-		if (r != LIBEVDEV_READ_STATUS_SYNC) /* just to be safe */
-			device->internals->require_sync = 0;
+	} else {
+		r = 0;
 	}
+	r += (ssize_t)(dequeued * sizeof(*device->internals->evbuf));
 
-	eventp->sync_event = (r == LIBEVDEV_READ_STATUS_SYNC);
-	eventp->code = ev.code;
-	eventp->value = ev.value;
-	eventp->time.tv_sec = ev.input_event_sec;
-	eventp->time.tv_usec = ev.input_event_usec;
+	i = 0;
+	for (ev = device->internals->evbuf; r; r -= (ssize_t)sizeof(*device->internals->evbuf), ev++) {
+		events[i].code = ev->code;
+		events[i].value = ev->value;
+		events[i].time.tv_sec = ev->input_event_sec;
+		events[i].time.tv_usec = ev->input_event_usec;
 
-	switch (ev.type) {
-	case EV_KEY:
-		eventp->type = LIBGAMEPAD_BUTTON;
-		return 1;
+		switch (ev->type) {
+		case EV_SYN:
+			events[i].code = 0;
+			events[i].value = 0;
+			if (ev->code == SYN_REPORT) {
+				events[i++].type = LIBGAMEPAD_EVENT_END;
+			} else if (ev->code == SYN_DROPPED) {
+				device->internals->require_sync = device->auto_sync;
+				events[i++].type = LIBGAMEPAD_EVENT_DROP;
+				goto out;
+			}
+			break;
 
-	case EV_ABS:
-		eventp->type = LIBGAMEPAD_ABSOLUTE_AXIS;
-		return 1;
+		case EV_KEY:
+			ev->value = !!ev->value;
+			if (update_button(device, ev->code, ev->value))
+				events[i++].type = LIBGAMEPAD_BUTTON;
+			break;
 
-	case EV_REL:
-		eventp->type = LIBGAMEPAD_RELATIVE_AXIS;
-		return 1;
+		case EV_REL:
+			events[i++].type = LIBGAMEPAD_RELATIVE_AXIS;
+			break;
 
-	case EV_SYN:
-		if (ev.code == SYN_DROPPED)
-			device->internals->require_sync = 1;
-		return 0;
+		case EV_ABS:
+			if (update_absolute_axis(device, ev->code, ev->value))
+				events[i++].type = LIBGAMEPAD_ABSOLUTE_AXIS;
+			break;
 
-	default:
-		return 0;
+		default:
+			break;
+		}
+	}
+
+out:
+	if (dequeued) {
+		device->internals->ev_queued -= dequeued;
+		memmove(&device->internals->evbuf[0], &device->internals->evbuf[dequeued],
+		        device->internals->ev_queued * sizeof(*device->internals->evbuf));
 	}
+	return (ssize_t)i;
 }