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Diffstat (limited to 'Radio/HW/RtlSdr/libusb/os/events_posix.c')
-rw-r--r--Radio/HW/RtlSdr/libusb/os/events_posix.c300
1 files changed, 300 insertions, 0 deletions
diff --git a/Radio/HW/RtlSdr/libusb/os/events_posix.c b/Radio/HW/RtlSdr/libusb/os/events_posix.c
new file mode 100644
index 0000000..715a2d5
--- /dev/null
+++ b/Radio/HW/RtlSdr/libusb/os/events_posix.c
@@ -0,0 +1,300 @@
+/*
+ * libusb event abstraction on POSIX platforms
+ *
+ * Copyright © 2020 Chris Dickens <christopher.a.dickens@gmail.com>
+ *
+ * This library is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU Lesser General Public
+ * License as published by the Free Software Foundation; either
+ * version 2.1 of the License, or (at your option) any later version.
+ *
+ * This library is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
+ * Lesser General Public License for more details.
+ *
+ * You should have received a copy of the GNU Lesser General Public
+ * License along with this library; if not, write to the Free Software
+ * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
+ */
+
+#include "libusbi.h"
+
+#include <errno.h>
+#include <fcntl.h>
+#ifdef HAVE_EVENTFD
+#include <sys/eventfd.h>
+#endif
+#ifdef HAVE_TIMERFD
+#include <sys/timerfd.h>
+#endif
+#include <unistd.h>
+
+#ifdef HAVE_EVENTFD
+#define EVENT_READ_FD(e) ((e)->eventfd)
+#define EVENT_WRITE_FD(e) ((e)->eventfd)
+#else
+#define EVENT_READ_FD(e) ((e)->pipefd[0])
+#define EVENT_WRITE_FD(e) ((e)->pipefd[1])
+#endif
+
+#ifdef HAVE_NFDS_T
+typedef nfds_t usbi_nfds_t;
+#else
+typedef unsigned int usbi_nfds_t;
+#endif
+
+int usbi_create_event(usbi_event_t *event)
+{
+#ifdef HAVE_EVENTFD
+ event->eventfd = eventfd(0, EFD_NONBLOCK | EFD_CLOEXEC);
+ if (event->eventfd == -1) {
+ usbi_err(NULL, "failed to create eventfd, errno=%d", errno);
+ return LIBUSB_ERROR_OTHER;
+ }
+
+ return 0;
+#else
+#if defined(HAVE_PIPE2)
+ int ret = pipe2(event->pipefd, O_CLOEXEC);
+#else
+ int ret = pipe(event->pipefd);
+#endif
+
+ if (ret != 0) {
+ usbi_err(NULL, "failed to create pipe, errno=%d", errno);
+ return LIBUSB_ERROR_OTHER;
+ }
+
+#if !defined(HAVE_PIPE2) && defined(FD_CLOEXEC)
+ ret = fcntl(event->pipefd[0], F_GETFD);
+ if (ret == -1) {
+ usbi_err(NULL, "failed to get pipe fd flags, errno=%d", errno);
+ goto err_close_pipe;
+ }
+ ret = fcntl(event->pipefd[0], F_SETFD, ret | FD_CLOEXEC);
+ if (ret == -1) {
+ usbi_err(NULL, "failed to set pipe fd flags, errno=%d", errno);
+ goto err_close_pipe;
+ }
+
+ ret = fcntl(event->pipefd[1], F_GETFD);
+ if (ret == -1) {
+ usbi_err(NULL, "failed to get pipe fd flags, errno=%d", errno);
+ goto err_close_pipe;
+ }
+ ret = fcntl(event->pipefd[1], F_SETFD, ret | FD_CLOEXEC);
+ if (ret == -1) {
+ usbi_err(NULL, "failed to set pipe fd flags, errno=%d", errno);
+ goto err_close_pipe;
+ }
+#endif
+
+ ret = fcntl(event->pipefd[1], F_GETFL);
+ if (ret == -1) {
+ usbi_err(NULL, "failed to get pipe fd status flags, errno=%d", errno);
+ goto err_close_pipe;
+ }
+ ret = fcntl(event->pipefd[1], F_SETFL, ret | O_NONBLOCK);
+ if (ret == -1) {
+ usbi_err(NULL, "failed to set pipe fd status flags, errno=%d", errno);
+ goto err_close_pipe;
+ }
+
+ return 0;
+
+err_close_pipe:
+ close(event->pipefd[1]);
+ close(event->pipefd[0]);
+ return LIBUSB_ERROR_OTHER;
+#endif
+}
+
+void usbi_destroy_event(usbi_event_t *event)
+{
+#ifdef HAVE_EVENTFD
+ if (close(event->eventfd) == -1)
+ usbi_warn(NULL, "failed to close eventfd, errno=%d", errno);
+#else
+ if (close(event->pipefd[1]) == -1)
+ usbi_warn(NULL, "failed to close pipe write end, errno=%d", errno);
+ if (close(event->pipefd[0]) == -1)
+ usbi_warn(NULL, "failed to close pipe read end, errno=%d", errno);
+#endif
+}
+
+void usbi_signal_event(usbi_event_t *event)
+{
+ uint64_t dummy = 1;
+ ssize_t r;
+
+ r = write(EVENT_WRITE_FD(event), &dummy, sizeof(dummy));
+ if (r != sizeof(dummy))
+ usbi_warn(NULL, "event write failed");
+}
+
+void usbi_clear_event(usbi_event_t *event)
+{
+ uint64_t dummy;
+ ssize_t r;
+
+ r = read(EVENT_READ_FD(event), &dummy, sizeof(dummy));
+ if (r != sizeof(dummy))
+ usbi_warn(NULL, "event read failed");
+}
+
+#ifdef HAVE_TIMERFD
+int usbi_create_timer(usbi_timer_t *timer)
+{
+ timer->timerfd = timerfd_create(CLOCK_MONOTONIC, TFD_NONBLOCK | TFD_CLOEXEC);
+ if (timer->timerfd == -1) {
+ usbi_warn(NULL, "failed to create timerfd, errno=%d", errno);
+ return LIBUSB_ERROR_OTHER;
+ }
+
+ return 0;
+}
+
+void usbi_destroy_timer(usbi_timer_t *timer)
+{
+ if (close(timer->timerfd) == -1)
+ usbi_warn(NULL, "failed to close timerfd, errno=%d", errno);
+}
+
+int usbi_arm_timer(usbi_timer_t *timer, const struct timespec *timeout)
+{
+ const struct itimerspec it = { { 0, 0 }, { timeout->tv_sec, timeout->tv_nsec } };
+
+ if (timerfd_settime(timer->timerfd, TFD_TIMER_ABSTIME, &it, NULL) == -1) {
+ usbi_warn(NULL, "failed to arm timerfd, errno=%d", errno);
+ return LIBUSB_ERROR_OTHER;
+ }
+
+ return 0;
+}
+
+int usbi_disarm_timer(usbi_timer_t *timer)
+{
+ const struct itimerspec it = { { 0, 0 }, { 0, 0 } };
+
+ if (timerfd_settime(timer->timerfd, 0, &it, NULL) == -1) {
+ usbi_warn(NULL, "failed to disarm timerfd, errno=%d", errno);
+ return LIBUSB_ERROR_OTHER;
+ }
+
+ return 0;
+}
+#endif
+
+int usbi_alloc_event_data(struct libusb_context *ctx)
+{
+ struct usbi_event_source *ievent_source;
+ struct pollfd *fds;
+ size_t i = 0;
+
+ if (ctx->event_data) {
+ free(ctx->event_data);
+ ctx->event_data = NULL;
+ }
+
+ ctx->event_data_cnt = 0;
+ for_each_event_source(ctx, ievent_source)
+ ctx->event_data_cnt++;
+
+ fds = calloc(ctx->event_data_cnt, sizeof(*fds));
+ if (!fds)
+ return LIBUSB_ERROR_NO_MEM;
+
+ for_each_event_source(ctx, ievent_source) {
+ fds[i].fd = ievent_source->data.os_handle;
+ fds[i].events = ievent_source->data.poll_events;
+ i++;
+ }
+
+ ctx->event_data = fds;
+ return 0;
+}
+
+int usbi_wait_for_events(struct libusb_context *ctx,
+ struct usbi_reported_events *reported_events, int timeout_ms)
+{
+ struct pollfd *fds = ctx->event_data;
+ usbi_nfds_t nfds = (usbi_nfds_t)ctx->event_data_cnt;
+ int internal_fds, num_ready;
+
+ usbi_dbg(ctx, "poll() %u fds with timeout in %dms", (unsigned int)nfds, timeout_ms);
+ num_ready = poll(fds, nfds, timeout_ms);
+ usbi_dbg(ctx, "poll() returned %d", num_ready);
+ if (num_ready == 0) {
+ if (usbi_using_timer(ctx))
+ goto done;
+ return LIBUSB_ERROR_TIMEOUT;
+ } else if (num_ready == -1) {
+ if (errno == EINTR)
+ return LIBUSB_ERROR_INTERRUPTED;
+ usbi_err(ctx, "poll() failed, errno=%d", errno);
+ return LIBUSB_ERROR_IO;
+ }
+
+ /* fds[0] is always the internal signalling event */
+ if (fds[0].revents) {
+ reported_events->event_triggered = 1;
+ num_ready--;
+ } else {
+ reported_events->event_triggered = 0;
+ }
+
+#ifdef HAVE_OS_TIMER
+ /* on timer configurations, fds[1] is the timer */
+ if (usbi_using_timer(ctx) && fds[1].revents) {
+ reported_events->timer_triggered = 1;
+ num_ready--;
+ } else {
+ reported_events->timer_triggered = 0;
+ }
+#endif
+
+ if (!num_ready)
+ goto done;
+
+ /* the backend will never need to attempt to handle events on the
+ * library's internal file descriptors, so we determine how many are
+ * in use internally for this context and skip these when passing any
+ * remaining pollfds to the backend. */
+ internal_fds = usbi_using_timer(ctx) ? 2 : 1;
+ fds += internal_fds;
+ nfds -= internal_fds;
+
+ usbi_mutex_lock(&ctx->event_data_lock);
+ if (ctx->event_flags & USBI_EVENT_EVENT_SOURCES_MODIFIED) {
+ struct usbi_event_source *ievent_source;
+
+ for_each_removed_event_source(ctx, ievent_source) {
+ usbi_nfds_t n;
+
+ for (n = 0; n < nfds; n++) {
+ if (ievent_source->data.os_handle != fds[n].fd)
+ continue;
+ if (!fds[n].revents)
+ continue;
+ /* pollfd was removed between the creation of the fds array and
+ * here. remove triggered revent as it is no longer relevant. */
+ usbi_dbg(ctx, "fd %d was removed, ignoring raised events", fds[n].fd);
+ fds[n].revents = 0;
+ num_ready--;
+ break;
+ }
+ }
+ }
+ usbi_mutex_unlock(&ctx->event_data_lock);
+
+ if (num_ready) {
+ assert(num_ready > 0);
+ reported_events->event_data = fds;
+ reported_events->event_data_count = (unsigned int)nfds;
+ }
+
+done:
+ reported_events->num_ready = num_ready;
+ return LIBUSB_SUCCESS;
+}