Travis Geiselbrecht | 1d0df69 | 2008-09-01 02:26:09 -0700 | [diff] [blame] | 1 | /* |
| 2 | * Copyright (c) 2008 Travis Geiselbrecht |
| 3 | * |
| 4 | * Permission is hereby granted, free of charge, to any person obtaining |
| 5 | * a copy of this software and associated documentation files |
| 6 | * (the "Software"), to deal in the Software without restriction, |
| 7 | * including without limitation the rights to use, copy, modify, merge, |
| 8 | * publish, distribute, sublicense, and/or sell copies of the Software, |
| 9 | * and to permit persons to whom the Software is furnished to do so, |
| 10 | * subject to the following conditions: |
| 11 | * |
| 12 | * The above copyright notice and this permission notice shall be |
| 13 | * included in all copies or substantial portions of the Software. |
| 14 | * |
| 15 | * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, |
| 16 | * EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF |
| 17 | * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. |
| 18 | * IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY |
| 19 | * CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, |
| 20 | * TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE |
| 21 | * SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE. |
| 22 | */ |
| 23 | #ifndef __KERNEL_EVENT_H |
| 24 | #define __KERNEL_EVENT_H |
| 25 | |
| 26 | #include <kernel/thread.h> |
| 27 | |
| 28 | #define EVENT_MAGIC 'evnt' |
| 29 | |
| 30 | typedef struct event { |
| 31 | int magic; |
| 32 | bool signalled; |
| 33 | uint flags; |
| 34 | wait_queue_t wait; |
| 35 | } event_t; |
| 36 | |
| 37 | #define EVENT_FLAG_AUTOUNSIGNAL 1 |
| 38 | |
Brian Swetland | a07d2fa | 2009-01-24 22:36:36 -0800 | [diff] [blame] | 39 | /* Rules for Events: |
| 40 | * - Events may be signaled from interrupt context *but* the reschedule |
| 41 | * parameter must be false in that case. |
| 42 | * - Events may not be waited upon from interrupt context. |
| 43 | * - Events without FLAG_AUTOUNSIGNAL: |
| 44 | * - Wake up any waiting threads when signaled. |
| 45 | * - Continue to do so (no threads will wait) until unsignaled. |
| 46 | * - Events with FLAG_AUTOUNSIGNAL: |
| 47 | * - If one or more threads are waiting when signaled, one thread will |
| 48 | * be woken up and return. The signaled state will not be set. |
| 49 | * - If no threads are waiting when signaled, the Event will remain |
| 50 | * in the signaled state until a thread attempts to wait (at which |
| 51 | * time it will unsignal atomicly and return immediately) or |
| 52 | * event_unsignal() is called. |
| 53 | */ |
| 54 | |
Travis Geiselbrecht | 1d0df69 | 2008-09-01 02:26:09 -0700 | [diff] [blame] | 55 | void event_init(event_t *, bool initial, uint flags); |
| 56 | void event_destroy(event_t *); |
| 57 | status_t event_wait(event_t *); |
| 58 | status_t event_wait_timeout(event_t *, time_t); /* wait on the event with a timeout */ |
| 59 | status_t event_signal(event_t *, bool reschedule); |
| 60 | status_t event_unsignal(event_t *); |
Travis Geiselbrecht | 12403e3 | 2010-05-06 13:36:57 -0700 | [diff] [blame] | 61 | #define event_initialized(e) ((e)->magic == EVENT_MAGIC) |
Travis Geiselbrecht | 1d0df69 | 2008-09-01 02:26:09 -0700 | [diff] [blame] | 62 | |
| 63 | #endif |
| 64 | |