diff options
Diffstat (limited to 'sys/dev/evdev/cdev.c')
| -rw-r--r-- | sys/dev/evdev/cdev.c | 860 |
1 files changed, 860 insertions, 0 deletions
diff --git a/sys/dev/evdev/cdev.c b/sys/dev/evdev/cdev.c new file mode 100644 index 0000000..fb81ace --- /dev/null +++ b/sys/dev/evdev/cdev.c @@ -0,0 +1,860 @@ +/*- + * Copyright (c) 2014 Jakub Wojciech Klama <jceel@FreeBSD.org> + * Copyright (c) 2015-2016 Vladimir Kondratyev <wulf@cicgroup.ru> + * All rights reserved. + * + * Redistribution and use in source and binary forms, with or without + * modification, are permitted provided that the following conditions + * are met: + * 1. Redistributions of source code must retain the above copyright + * notice, this list of conditions and the following disclaimer. + * 2. 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. + * + * THIS SOFTWARE IS PROVIDED BY THE AUTHOR 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 AUTHOR 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. + * + * $FreeBSD$ + */ + +#include "opt_evdev.h" + +#include <sys/types.h> +#include <sys/bitstring.h> +#include <sys/systm.h> +#include <sys/param.h> +#include <sys/kernel.h> +#include <sys/conf.h> +#include <sys/uio.h> +#include <sys/proc.h> +#include <sys/poll.h> +#include <sys/filio.h> +#include <sys/fcntl.h> +#include <sys/selinfo.h> +#include <sys/malloc.h> +#include <sys/time.h> + +#include <dev/evdev/input.h> +#include <dev/evdev/evdev.h> +#include <dev/evdev/evdev_private.h> + +#ifdef EVDEV_DEBUG +#define debugf(client, fmt, args...) printf("evdev cdev: "fmt"\n", ##args) +#else +#define debugf(client, fmt, args...) +#endif + +#define DEF_RING_REPORTS 8 + +static d_open_t evdev_open; +static d_read_t evdev_read; +static d_write_t evdev_write; +static d_ioctl_t evdev_ioctl; +static d_poll_t evdev_poll; +static d_kqfilter_t evdev_kqfilter; + +static int evdev_kqread(struct knote *kn, long hint); +static void evdev_kqdetach(struct knote *kn); +static void evdev_dtor(void *); +static int evdev_ioctl_eviocgbit(struct evdev_dev *, int, int, caddr_t); +static void evdev_client_filter_queue(struct evdev_client *, uint16_t); + +static struct cdevsw evdev_cdevsw = { + .d_version = D_VERSION, + .d_open = evdev_open, + .d_read = evdev_read, + .d_write = evdev_write, + .d_ioctl = evdev_ioctl, + .d_poll = evdev_poll, + .d_kqfilter = evdev_kqfilter, + .d_name = "evdev", +}; + +static struct filterops evdev_cdev_filterops = { + .f_isfd = 1, + .f_attach = NULL, + .f_detach = evdev_kqdetach, + .f_event = evdev_kqread, +}; + +static int +evdev_open(struct cdev *dev, int oflags, int devtype, struct thread *td) +{ + struct evdev_dev *evdev = dev->si_drv1; + struct evdev_client *client; + size_t buffer_size; + int ret; + + if (evdev == NULL) + return (ENODEV); + + /* Initialize client structure */ + buffer_size = evdev->ev_report_size * DEF_RING_REPORTS; + client = malloc(offsetof(struct evdev_client, ec_buffer) + + sizeof(struct input_event) * buffer_size, + M_EVDEV, M_WAITOK | M_ZERO); + + /* Initialize ring buffer */ + client->ec_buffer_size = buffer_size; + client->ec_buffer_head = 0; + client->ec_buffer_tail = 0; + client->ec_buffer_ready = 0; + + client->ec_evdev = evdev; + mtx_init(&client->ec_buffer_mtx, "evclient", "evdev", MTX_DEF); + knlist_init_mtx(&client->ec_selp.si_note, &client->ec_buffer_mtx); + + /* Avoid race with evdev_unregister */ + EVDEV_LOCK(evdev); + if (dev->si_drv1 == NULL) + ret = ENODEV; + else + ret = evdev_register_client(evdev, client); + + if (ret != 0) + evdev_revoke_client(client); + /* + * Unlock evdev here because non-sleepable lock held + * while calling devfs_set_cdevpriv upsets WITNESS + */ + EVDEV_UNLOCK(evdev); + + if (!ret) + ret = devfs_set_cdevpriv(client, evdev_dtor); + + if (ret != 0) { + debugf(client, "cannot register evdev client"); + evdev_dtor(client); + } + + return (ret); +} + +static void +evdev_dtor(void *data) +{ + struct evdev_client *client = (struct evdev_client *)data; + + EVDEV_LOCK(client->ec_evdev); + if (!client->ec_revoked) + evdev_dispose_client(client->ec_evdev, client); + EVDEV_UNLOCK(client->ec_evdev); + + knlist_clear(&client->ec_selp.si_note, 0); + seldrain(&client->ec_selp); + knlist_destroy(&client->ec_selp.si_note); + funsetown(&client->ec_sigio); + mtx_destroy(&client->ec_buffer_mtx); + free(client, M_EVDEV); +} + +static int +evdev_read(struct cdev *dev, struct uio *uio, int ioflag) +{ + struct evdev_client *client; + struct input_event *event; + int ret = 0; + int remaining; + + ret = devfs_get_cdevpriv((void **)&client); + if (ret != 0) + return (ret); + + debugf(client, "read %zd bytes by thread %d", uio->uio_resid, + uio->uio_td->td_tid); + + if (client->ec_revoked) + return (ENODEV); + + /* Zero-sized reads are allowed for error checking */ + if (uio->uio_resid != 0 && uio->uio_resid < sizeof(struct input_event)) + return (EINVAL); + + remaining = uio->uio_resid / sizeof(struct input_event); + + EVDEV_CLIENT_LOCKQ(client); + + if (EVDEV_CLIENT_EMPTYQ(client)) { + if (ioflag & O_NONBLOCK) + ret = EWOULDBLOCK; + else { + if (remaining != 0) { + client->ec_blocked = true; + ret = mtx_sleep(client, &client->ec_buffer_mtx, + PCATCH, "evread", 0); + } + } + } + + while (ret == 0 && !EVDEV_CLIENT_EMPTYQ(client) && remaining > 0) { + event = &client->ec_buffer[client->ec_buffer_head]; + client->ec_buffer_head = + (client->ec_buffer_head + 1) % client->ec_buffer_size; + remaining--; + + EVDEV_CLIENT_UNLOCKQ(client); + ret = uiomove(event, sizeof(struct input_event), uio); + EVDEV_CLIENT_LOCKQ(client); + } + + EVDEV_CLIENT_UNLOCKQ(client); + + return (ret); +} + +static int +evdev_write(struct cdev *dev, struct uio *uio, int ioflag) +{ + struct evdev_dev *evdev = dev->si_drv1; + struct evdev_client *client; + struct input_event event; + int ret = 0; + + ret = devfs_get_cdevpriv((void **)&client); + if (ret != 0) + return (ret); + + debugf(client, "write %zd bytes by thread %d", uio->uio_resid, + uio->uio_td->td_tid); + + if (client->ec_revoked || evdev == NULL) + return (ENODEV); + + if (uio->uio_resid % sizeof(struct input_event) != 0) { + debugf(client, "write size not multiple of input_event size"); + return (EINVAL); + } + + while (uio->uio_resid > 0 && ret == 0) { + ret = uiomove(&event, sizeof(struct input_event), uio); + if (ret == 0) + ret = evdev_inject_event(evdev, event.type, event.code, + event.value); + } + + return (ret); +} + +static int +evdev_poll(struct cdev *dev, int events, struct thread *td) +{ + struct evdev_client *client; + int ret; + int revents = 0; + + ret = devfs_get_cdevpriv((void **)&client); + if (ret != 0) + return (POLLNVAL); + + debugf(client, "poll by thread %d", td->td_tid); + + if (client->ec_revoked) + return (POLLHUP); + + if (events & (POLLIN | POLLRDNORM)) { + EVDEV_CLIENT_LOCKQ(client); + if (!EVDEV_CLIENT_EMPTYQ(client)) + revents = events & (POLLIN | POLLRDNORM); + else { + client->ec_selected = true; + selrecord(td, &client->ec_selp); + } + EVDEV_CLIENT_UNLOCKQ(client); + } + + return (revents); +} + +static int +evdev_kqfilter(struct cdev *dev, struct knote *kn) +{ + struct evdev_client *client; + int ret; + + ret = devfs_get_cdevpriv((void **)&client); + if (ret != 0) + return (ret); + + if (client->ec_revoked) + return (ENODEV); + + switch(kn->kn_filter) { + case EVFILT_READ: + kn->kn_fop = &evdev_cdev_filterops; + break; + default: + return(EINVAL); + } + kn->kn_hook = (caddr_t)client; + + knlist_add(&client->ec_selp.si_note, kn, 0); + return (0); +} + +static int +evdev_kqread(struct knote *kn, long hint) +{ + struct evdev_client *client; + int ret; + + client = (struct evdev_client *)kn->kn_hook; + + EVDEV_CLIENT_LOCKQ_ASSERT(client); + + if (client->ec_revoked) { + kn->kn_flags |= EV_EOF; + ret = 1; + } else { + kn->kn_data = EVDEV_CLIENT_SIZEQ(client) * + sizeof(struct input_event); + ret = !EVDEV_CLIENT_EMPTYQ(client); + } + return (ret); +} + +static void +evdev_kqdetach(struct knote *kn) +{ + struct evdev_client *client; + + client = (struct evdev_client *)kn->kn_hook; + knlist_remove(&client->ec_selp.si_note, kn, 0); +} + +static int +evdev_ioctl(struct cdev *dev, u_long cmd, caddr_t data, int fflag, + struct thread *td) +{ + struct evdev_dev *evdev = dev->si_drv1; + struct evdev_client *client; + struct input_keymap_entry *ke; + int ret, len, limit, type_num; + uint32_t code; + size_t nvalues; + + ret = devfs_get_cdevpriv((void **)&client); + if (ret != 0) + return (ret); + + if (client->ec_revoked || evdev == NULL) + return (ENODEV); + + /* file I/O ioctl handling */ + switch (cmd) { + case FIOSETOWN: + return (fsetown(*(int *)data, &client->ec_sigio)); + + case FIOGETOWN: + *(int *)data = fgetown(&client->ec_sigio); + return (0); + + case FIONBIO: + return (0); + + case FIOASYNC: + if (*(int *)data) + client->ec_async = true; + else + client->ec_async = false; + + return (0); + + case FIONREAD: + EVDEV_CLIENT_LOCKQ(client); + *(int *)data = + EVDEV_CLIENT_SIZEQ(client) * sizeof(struct input_event); + EVDEV_CLIENT_UNLOCKQ(client); + return (0); + } + + len = IOCPARM_LEN(cmd); + debugf(client, "ioctl called: cmd=0x%08lx, data=%p", cmd, data); + + /* evdev fixed-length ioctls handling */ + switch (cmd) { + case EVIOCGVERSION: + *(int *)data = EV_VERSION; + return (0); + + case EVIOCGID: + debugf(client, "EVIOCGID: bus=%d vendor=0x%04x product=0x%04x", + evdev->ev_id.bustype, evdev->ev_id.vendor, + evdev->ev_id.product); + memcpy(data, &evdev->ev_id, sizeof(struct input_id)); + return (0); + + case EVIOCGREP: + if (!evdev_event_supported(evdev, EV_REP)) + return (ENOTSUP); + + memcpy(data, evdev->ev_rep, sizeof(evdev->ev_rep)); + return (0); + + case EVIOCSREP: + if (!evdev_event_supported(evdev, EV_REP)) + return (ENOTSUP); + + evdev_inject_event(evdev, EV_REP, REP_DELAY, ((int *)data)[0]); + evdev_inject_event(evdev, EV_REP, REP_PERIOD, + ((int *)data)[1]); + return (0); + + case EVIOCGKEYCODE: + /* Fake unsupported ioctl */ + return (0); + + case EVIOCGKEYCODE_V2: + if (evdev->ev_methods == NULL || + evdev->ev_methods->ev_get_keycode == NULL) + return (ENOTSUP); + + ke = (struct input_keymap_entry *)data; + evdev->ev_methods->ev_get_keycode(evdev, evdev->ev_softc, ke); + return (0); + + case EVIOCSKEYCODE: + /* Fake unsupported ioctl */ + return (0); + + case EVIOCSKEYCODE_V2: + if (evdev->ev_methods == NULL || + evdev->ev_methods->ev_set_keycode == NULL) + return (ENOTSUP); + + ke = (struct input_keymap_entry *)data; + evdev->ev_methods->ev_set_keycode(evdev, evdev->ev_softc, ke); + return (0); + + case EVIOCGABS(0) ... EVIOCGABS(ABS_MAX): + if (evdev->ev_absinfo == NULL) + return (EINVAL); + + memcpy(data, &evdev->ev_absinfo[cmd - EVIOCGABS(0)], + sizeof(struct input_absinfo)); + return (0); + + case EVIOCSABS(0) ... EVIOCSABS(ABS_MAX): + if (evdev->ev_absinfo == NULL) + return (EINVAL); + + code = cmd - EVIOCSABS(0); + /* mt-slot number can not be changed */ + if (code == ABS_MT_SLOT) + return (EINVAL); + + EVDEV_LOCK(evdev); + evdev_set_absinfo(evdev, code, (struct input_absinfo *)data); + EVDEV_UNLOCK(evdev); + return (0); + + case EVIOCSFF: + case EVIOCRMFF: + case EVIOCGEFFECTS: + /* Fake unsupported ioctls */ + return (0); + + case EVIOCGRAB: + EVDEV_LOCK(evdev); + if (*(int *)data) + ret = evdev_grab_client(evdev, client); + else + ret = evdev_release_client(evdev, client); + EVDEV_UNLOCK(evdev); + return (ret); + + case EVIOCREVOKE: + if (*(int *)data != 0) + return (EINVAL); + + EVDEV_LOCK(evdev); + if (dev->si_drv1 != NULL && !client->ec_revoked) { + evdev_dispose_client(evdev, client); + evdev_revoke_client(client); + } + EVDEV_UNLOCK(evdev); + return (0); + + case EVIOCSCLOCKID: + switch (*(int *)data) { + case CLOCK_REALTIME: + client->ec_clock_id = EV_CLOCK_REALTIME; + return (0); + case CLOCK_MONOTONIC: + client->ec_clock_id = EV_CLOCK_MONOTONIC; + return (0); + default: + return (EINVAL); + } + } + + /* evdev variable-length ioctls handling */ + switch (IOCBASECMD(cmd)) { + case EVIOCGNAME(0): + strlcpy(data, evdev->ev_name, len); + return (0); + + case EVIOCGPHYS(0): + if (evdev->ev_shortname[0] == 0) + return (ENOENT); + + strlcpy(data, evdev->ev_shortname, len); + return (0); + + case EVIOCGUNIQ(0): + if (evdev->ev_serial[0] == 0) + return (ENOENT); + + strlcpy(data, evdev->ev_serial, len); + return (0); + + case EVIOCGPROP(0): + limit = MIN(len, bitstr_size(INPUT_PROP_CNT)); + memcpy(data, evdev->ev_prop_flags, limit); + return (0); + + case EVIOCGMTSLOTS(0): + if (evdev->ev_mt == NULL) + return (EINVAL); + if (len < sizeof(uint32_t)) + return (EINVAL); + code = *(uint32_t *)data; + if (!ABS_IS_MT(code)) + return (EINVAL); + + nvalues = + MIN(len / sizeof(int32_t) - 1, MAXIMAL_MT_SLOT(evdev) + 1); + for (int i = 0; i < nvalues; i++) + ((int32_t *)data)[i + 1] = + evdev_get_mt_value(evdev, i, code); + return (0); + + case EVIOCGKEY(0): + limit = MIN(len, bitstr_size(KEY_CNT)); + EVDEV_LOCK(evdev); + evdev_client_filter_queue(client, EV_KEY); + memcpy(data, evdev->ev_key_states, limit); + EVDEV_UNLOCK(evdev); + return (0); + + case EVIOCGLED(0): + limit = MIN(len, bitstr_size(LED_CNT)); + EVDEV_LOCK(evdev); + evdev_client_filter_queue(client, EV_LED); + memcpy(data, evdev->ev_led_states, limit); + EVDEV_UNLOCK(evdev); + return (0); + + case EVIOCGSND(0): + limit = MIN(len, bitstr_size(SND_CNT)); + EVDEV_LOCK(evdev); + evdev_client_filter_queue(client, EV_SND); + memcpy(data, evdev->ev_snd_states, limit); + EVDEV_UNLOCK(evdev); + return (0); + + case EVIOCGSW(0): + limit = MIN(len, bitstr_size(SW_CNT)); + EVDEV_LOCK(evdev); + evdev_client_filter_queue(client, EV_SW); + memcpy(data, evdev->ev_sw_states, limit); + EVDEV_UNLOCK(evdev); + return (0); + + case EVIOCGBIT(0, 0) ... EVIOCGBIT(EV_MAX, 0): + type_num = IOCBASECMD(cmd) - EVIOCGBIT(0, 0); + debugf(client, "EVIOCGBIT(%d): data=%p, len=%d", type_num, + data, len); + return (evdev_ioctl_eviocgbit(evdev, type_num, len, data)); + } + + return (EINVAL); +} + +static int +evdev_ioctl_eviocgbit(struct evdev_dev *evdev, int type, int len, caddr_t data) +{ + unsigned long *bitmap; + int limit; + + switch (type) { + case 0: + bitmap = evdev->ev_type_flags; + limit = EV_CNT; + break; + case EV_KEY: + bitmap = evdev->ev_key_flags; + limit = KEY_CNT; + break; + case EV_REL: + bitmap = evdev->ev_rel_flags; + limit = REL_CNT; + break; + case EV_ABS: + bitmap = evdev->ev_abs_flags; + limit = ABS_CNT; + break; + case EV_MSC: + bitmap = evdev->ev_msc_flags; + limit = MSC_CNT; + break; + case EV_LED: + bitmap = evdev->ev_led_flags; + limit = LED_CNT; + break; + case EV_SND: + bitmap = evdev->ev_snd_flags; + limit = SND_CNT; + break; + case EV_SW: + bitmap = evdev->ev_sw_flags; + limit = SW_CNT; + break; + case EV_FF: + /* + * We don't support EV_FF now, so let's + * just fake it returning only zeros. + */ + bzero(data, len); + return (0); + default: + return (ENOTTY); + } + + /* + * Clear ioctl data buffer in case it's bigger than + * bitmap size + */ + bzero(data, len); + + limit = bitstr_size(limit); + len = MIN(limit, len); + memcpy(data, bitmap, len); + return (0); +} + +void +evdev_revoke_client(struct evdev_client *client) +{ + + EVDEV_LOCK_ASSERT(client->ec_evdev); + + client->ec_revoked = true; +} + +void +evdev_notify_event(struct evdev_client *client) +{ + + EVDEV_CLIENT_LOCKQ_ASSERT(client); + + if (client->ec_blocked) { + client->ec_blocked = false; + wakeup(client); + } + if (client->ec_selected) { + client->ec_selected = false; + selwakeup(&client->ec_selp); + } + KNOTE_LOCKED(&client->ec_selp.si_note, 0); + + if (client->ec_async && client->ec_sigio != NULL) + pgsigio(&client->ec_sigio, SIGIO, 0); +} + +int +evdev_cdev_create(struct evdev_dev *evdev) +{ + struct make_dev_args mda; + int ret, unit = 0; + + make_dev_args_init(&mda); + mda.mda_flags = MAKEDEV_WAITOK | MAKEDEV_CHECKNAME; + mda.mda_devsw = &evdev_cdevsw; + mda.mda_uid = UID_ROOT; + mda.mda_gid = GID_WHEEL; + mda.mda_mode = 0600; + mda.mda_si_drv1 = evdev; + + /* Try to coexist with cuse-backed input/event devices */ + while ((ret = make_dev_s(&mda, &evdev->ev_cdev, "input/event%d", unit)) + == EEXIST) + unit++; + + if (ret == 0) + evdev->ev_unit = unit; + + return (ret); +} + +int +evdev_cdev_destroy(struct evdev_dev *evdev) +{ + + destroy_dev(evdev->ev_cdev); + return (0); +} + +static void +evdev_client_gettime(struct evdev_client *client, struct timeval *tv) +{ + + switch (client->ec_clock_id) { + case EV_CLOCK_BOOTTIME: + /* + * XXX: FreeBSD does not support true POSIX monotonic clock. + * So aliase EV_CLOCK_BOOTTIME to EV_CLOCK_MONOTONIC. + */ + case EV_CLOCK_MONOTONIC: + microuptime(tv); + break; + + case EV_CLOCK_REALTIME: + default: + microtime(tv); + break; + } +} + +void +evdev_client_push(struct evdev_client *client, uint16_t type, uint16_t code, + int32_t value) +{ + struct timeval time; + size_t count, head, tail, ready; + + EVDEV_CLIENT_LOCKQ_ASSERT(client); + head = client->ec_buffer_head; + tail = client->ec_buffer_tail; + ready = client->ec_buffer_ready; + count = client->ec_buffer_size; + + /* If queue is full drop its content and place SYN_DROPPED event */ + if ((tail + 1) % count == head) { + debugf(client, "client %p: buffer overflow", client); + + head = (tail + count - 1) % count; + client->ec_buffer[head] = (struct input_event) { + .type = EV_SYN, + .code = SYN_DROPPED, + .value = 0 + }; + /* + * XXX: Here is a small race window from now till the end of + * report. The queue is empty but client has been already + * notified of data readyness. Can be fixed in two ways: + * 1. Implement bulk insert so queue lock would not be dropped + * till the SYN_REPORT event. + * 2. Insert SYN_REPORT just now and skip remaining events + */ + client->ec_buffer_head = head; + client->ec_buffer_ready = head; + } + + client->ec_buffer[tail].type = type; + client->ec_buffer[tail].code = code; + client->ec_buffer[tail].value = value; + client->ec_buffer_tail = (tail + 1) % count; + + /* Allow users to read events only after report has been completed */ + if (type == EV_SYN && code == SYN_REPORT) { + evdev_client_gettime(client, &time); + for (; ready != client->ec_buffer_tail; + ready = (ready + 1) % count) + client->ec_buffer[ready].time = time; + client->ec_buffer_ready = client->ec_buffer_tail; + } +} + +void +evdev_client_dumpqueue(struct evdev_client *client) +{ + struct input_event *event; + size_t i, head, tail, ready, size; + + head = client->ec_buffer_head; + tail = client->ec_buffer_tail; + ready = client->ec_buffer_ready; + size = client->ec_buffer_size; + + printf("evdev client: %p\n", client); + printf("event queue: head=%zu ready=%zu tail=%zu size=%zu\n", + head, ready, tail, size); + + printf("queue contents:\n"); + + for (i = 0; i < size; i++) { + event = &client->ec_buffer[i]; + printf("%zu: ", i); + + if (i < head || i > tail) + printf("unused\n"); + else + printf("type=%d code=%d value=%d ", event->type, + event->code, event->value); + + if (i == head) + printf("<- head\n"); + else if (i == tail) + printf("<- tail\n"); + else if (i == ready) + printf("<- ready\n"); + else + printf("\n"); + } +} + +static void +evdev_client_filter_queue(struct evdev_client *client, uint16_t type) +{ + struct input_event *event; + size_t head, tail, count, i; + bool last_was_syn = false; + + EVDEV_CLIENT_LOCKQ(client); + + i = head = client->ec_buffer_head; + tail = client->ec_buffer_tail; + count = client->ec_buffer_size; + client->ec_buffer_ready = client->ec_buffer_tail; + + while (i != client->ec_buffer_tail) { + event = &client->ec_buffer[i]; + i = (i + 1) % count; + + /* Skip event of given type */ + if (event->type == type) + continue; + + /* Remove empty SYN_REPORT events */ + if (event->type == EV_SYN && event->code == SYN_REPORT) { + if (last_was_syn) + continue; + else + client->ec_buffer_ready = (tail + 1) % count; + } + + /* Rewrite entry */ + memcpy(&client->ec_buffer[tail], event, + sizeof(struct input_event)); + + last_was_syn = (event->type == EV_SYN && + event->code == SYN_REPORT); + + tail = (tail + 1) % count; + } + + client->ec_buffer_head = i; + client->ec_buffer_tail = tail; + + EVDEV_CLIENT_UNLOCKQ(client); +} |
