| /* |
| * Copyright (c) 2008 Travis Geiselbrecht |
| * |
| * 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 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 <debug.h> |
| #include <err.h> |
| #include <kernel/event.h> |
| |
| #if DEBUGLEVEL > 1 |
| #define EVENT_CHECK 1 |
| #endif |
| |
| void event_init(event_t *e, bool initial, uint flags) |
| { |
| #if EVENT_CHECK |
| // ASSERT(e->magic != EVENT_MAGIC); |
| #endif |
| |
| e->magic = EVENT_MAGIC; |
| e->signalled = initial; |
| e->flags = flags; |
| wait_queue_init(&e->wait); |
| } |
| |
| void event_destroy(event_t *e) |
| { |
| enter_critical_section(); |
| |
| #if EVENT_CHECK |
| ASSERT(e->magic == EVENT_MAGIC); |
| #endif |
| |
| e->magic = 0; |
| e->signalled = false; |
| e->flags = 0; |
| wait_queue_destroy(&e->wait, true); |
| |
| exit_critical_section(); |
| } |
| |
| status_t event_wait_timeout(event_t *e, time_t timeout) |
| { |
| status_t ret = NO_ERROR; |
| |
| enter_critical_section(); |
| |
| #if EVENT_CHECK |
| ASSERT(e->magic == EVENT_MAGIC); |
| #endif |
| |
| if (e->signalled) { |
| /* signalled, we're going to fall through */ |
| if (e->flags & EVENT_FLAG_AUTOUNSIGNAL) { |
| /* autounsignal flag lets one thread fall through before unsignalling */ |
| e->signalled = false; |
| } |
| } else { |
| /* unsignalled, block here */ |
| ret = wait_queue_block(&e->wait, timeout); |
| if (ret < 0) |
| goto err; |
| } |
| |
| err: |
| exit_critical_section(); |
| |
| return ret; |
| } |
| |
| status_t event_wait(event_t *e) |
| { |
| return event_wait_timeout(e, INFINITE_TIME); |
| } |
| |
| status_t event_signal(event_t *e, bool reschedule) |
| { |
| enter_critical_section(); |
| |
| #if EVENT_CHECK |
| ASSERT(e->magic == EVENT_MAGIC); |
| #endif |
| |
| if (!e->signalled) { |
| if (e->flags & EVENT_FLAG_AUTOUNSIGNAL) { |
| /* try to release one thread and leave unsignalled if successful */ |
| if (wait_queue_wake_one(&e->wait, reschedule, NO_ERROR) <= 0) { |
| /* |
| * if we didn't actually find a thread to wake up, go to |
| * signalled state and let the next call to event_wait |
| * unsignal the event. |
| */ |
| e->signalled = true; |
| } |
| } else { |
| /* release all threads and remain signalled */ |
| e->signalled = true; |
| wait_queue_wake_all(&e->wait, reschedule, NO_ERROR); |
| } |
| } |
| |
| exit_critical_section(); |
| |
| return NO_ERROR; |
| } |
| |
| status_t event_unsignal(event_t *e) |
| { |
| enter_critical_section(); |
| |
| #if EVENT_CHECK |
| ASSERT(e->magic == EVENT_MAGIC); |
| #endif |
| |
| e->signalled = false; |
| |
| exit_critical_section(); |
| |
| return NO_ERROR; |
| } |
| |