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/*****************************************************************************
*
* mtdev - MT device event converter (MIT license)
*
* Copyright (C) 2010 Henrik Rydberg <rydberg@euromail.se>
* Copyright (C) 2010 Canonical Ltd.
*
* Permission is hereby granted, free of charge, to any person obtaining a
* copy of this software and associated documentation files (the "Software"),
* to deal in the Software without restriction, including without limitation
* the rights to use, copy, modify, merge, publish, distribute, sublicense,
* and/or sell copies of the Software, and to permit persons to whom the
* Software is furnished to do so, subject to the following conditions:
*
* The above copyright notice and this permission notice (including the next
* paragraph) shall be included in all copies or substantial portions of the
* Software.
*
* THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
* IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
* FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL
* THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
* LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
* FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER
* DEALINGS IN THE SOFTWARE.
*
****************************************************************************/
#include "iobuf.h"
#include "state.h"
#include <poll.h>
int mtdev_idle(struct mtdev *dev, int fd, int ms)
{
struct mtdev_state *state = dev->state;
struct mtdev_iobuf *buf = &state->iobuf;
struct pollfd fds = { fd, POLLIN, 0 };
return evbuf_empty(&state->outbuf) &&
evbuf_empty(&state->inbuf) &&
buf->head == buf->tail &&
poll(&fds, 1, ms) <= 0;
}
int mtdev_fetch(struct mtdev *dev, int fd, struct input_event *ev)
{
struct mtdev_iobuf *buf = &dev->state->iobuf;
int n = buf->head - buf->tail;
if (n < EVENT_SIZE) {
if (buf->tail && n > 0)
memmove(buf->data, buf->data + buf->tail, n);
buf->head = n;
buf->tail = 0;
SYSCALL(n = read(fd, buf->data + buf->head,
DIM_BUFFER - buf->head));
if (n <= 0)
return n;
buf->head += n;
}
if (buf->head - buf->tail < EVENT_SIZE)
return 0;
memcpy(ev, buf->data + buf->tail, EVENT_SIZE);
buf->tail += EVENT_SIZE;
return 1;
}
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)
return ret;
if (ret == 0)
break;
mtdev_put(dev, &ev);
count++;
}
return count;
}
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