| /* $Id$ */ |
| /* |
| * Copyright (C) 2008-2009 Teluu Inc. (http://www.teluu.com) |
| * Copyright (C) 2003-2008 Benny Prijono <benny@prijono.org> |
| * |
| * This program is free software; you can redistribute it and/or modify |
| * it under the terms of the GNU General Public License as published by |
| * the Free Software Foundation; either version 2 of the License, or |
| * (at your option) any later version. |
| * |
| * This program 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 General Public License for more details. |
| * |
| * You should have received a copy of the GNU General Public License |
| * along with this program; if not, write to the Free Software |
| * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA |
| */ |
| #include <pjmedia/clock.h> |
| #include <pjmedia/errno.h> |
| #include <pj/assert.h> |
| #include <pj/lock.h> |
| #include <pj/os.h> |
| #include <pj/pool.h> |
| |
| |
| /* |
| * Implementation of media clock with OS thread. |
| */ |
| |
| struct pjmedia_clock |
| { |
| pj_timestamp freq; |
| pj_timestamp interval; |
| pj_timestamp next_tick; |
| pj_timestamp timestamp; |
| unsigned samples_per_frame; |
| unsigned options; |
| pj_uint64_t max_jump; |
| pjmedia_clock_callback *cb; |
| void *user_data; |
| pj_thread_t *thread; |
| pj_bool_t running; |
| pj_bool_t quitting; |
| pj_lock_t *lock; |
| }; |
| |
| |
| static int clock_thread(void *arg); |
| |
| #define MAX_JUMP_MSEC 500 |
| |
| /* |
| * Create media clock. |
| */ |
| PJ_DEF(pj_status_t) pjmedia_clock_create( pj_pool_t *pool, |
| unsigned clock_rate, |
| unsigned channel_count, |
| unsigned samples_per_frame, |
| unsigned options, |
| pjmedia_clock_callback *cb, |
| void *user_data, |
| pjmedia_clock **p_clock) |
| { |
| pjmedia_clock *clock; |
| pj_status_t status; |
| |
| PJ_ASSERT_RETURN(pool && clock_rate && samples_per_frame && p_clock, |
| PJ_EINVAL); |
| |
| clock = PJ_POOL_ALLOC_T(pool, pjmedia_clock); |
| |
| |
| status = pj_get_timestamp_freq(&clock->freq); |
| if (status != PJ_SUCCESS) |
| return status; |
| |
| clock->interval.u64 = samples_per_frame * clock->freq.u64 / |
| channel_count / clock_rate; |
| clock->next_tick.u64 = 0; |
| clock->timestamp.u64 = 0; |
| clock->max_jump = MAX_JUMP_MSEC * clock->freq.u64 / 1000; |
| clock->samples_per_frame = samples_per_frame; |
| clock->options = options; |
| clock->cb = cb; |
| clock->user_data = user_data; |
| clock->thread = NULL; |
| clock->running = PJ_FALSE; |
| clock->quitting = PJ_FALSE; |
| |
| /* I don't think we need a mutex, so we'll use null. */ |
| status = pj_lock_create_null_mutex(pool, "clock", &clock->lock); |
| if (status != PJ_SUCCESS) |
| return status; |
| |
| if ((clock->options & PJMEDIA_CLOCK_NO_ASYNC) == 0) { |
| status = pj_thread_create(pool, "clock", &clock_thread, clock, |
| 0, 0, &clock->thread); |
| if (status != PJ_SUCCESS) { |
| pj_lock_destroy(clock->lock); |
| return status; |
| } |
| } |
| |
| |
| *p_clock = clock; |
| |
| return PJ_SUCCESS; |
| } |
| |
| |
| /* |
| * Start the clock. |
| */ |
| PJ_DEF(pj_status_t) pjmedia_clock_start(pjmedia_clock *clock) |
| { |
| pj_timestamp now; |
| pj_status_t status; |
| |
| PJ_ASSERT_RETURN(clock != NULL, PJ_EINVAL); |
| |
| if (clock->running) |
| return PJ_SUCCESS; |
| |
| status = pj_get_timestamp(&now); |
| if (status != PJ_SUCCESS) |
| return status; |
| |
| pj_lock_acquire(clock->lock); |
| clock->next_tick.u64 = now.u64 + clock->interval.u64; |
| clock->running = PJ_TRUE; |
| pj_lock_release(clock->lock); |
| |
| return status; |
| } |
| |
| |
| /* |
| * Stop the clock. |
| */ |
| PJ_DEF(pj_status_t) pjmedia_clock_stop(pjmedia_clock *clock) |
| { |
| PJ_ASSERT_RETURN(clock != NULL, PJ_EINVAL); |
| |
| clock->running = PJ_FALSE; |
| |
| return PJ_SUCCESS; |
| } |
| |
| |
| /* Calculate next tick */ |
| PJ_INLINE(void) clock_calc_next_tick(pjmedia_clock *clock, |
| pj_timestamp *now) |
| { |
| if (clock->next_tick.u64+clock->max_jump < now->u64) { |
| /* Timestamp has made large jump, adjust next_tick */ |
| clock->next_tick.u64 = now->u64; |
| } |
| clock->next_tick.u64 += clock->interval.u64; |
| |
| } |
| |
| /* |
| * Poll the clock. |
| */ |
| PJ_DEF(pj_bool_t) pjmedia_clock_wait( pjmedia_clock *clock, |
| pj_bool_t wait, |
| pj_timestamp *ts) |
| { |
| pj_timestamp now; |
| pj_status_t status; |
| |
| PJ_ASSERT_RETURN(clock != NULL, PJ_FALSE); |
| PJ_ASSERT_RETURN((clock->options & PJMEDIA_CLOCK_NO_ASYNC) != 0, |
| PJ_FALSE); |
| PJ_ASSERT_RETURN(clock->running, PJ_FALSE); |
| |
| status = pj_get_timestamp(&now); |
| if (status != PJ_SUCCESS) |
| return PJ_FALSE; |
| |
| /* Wait for the next tick to happen */ |
| if (now.u64 < clock->next_tick.u64) { |
| unsigned msec; |
| |
| if (!wait) |
| return PJ_FALSE; |
| |
| msec = pj_elapsed_msec(&now, &clock->next_tick); |
| pj_thread_sleep(msec); |
| } |
| |
| /* Call callback, if any */ |
| if (clock->cb) |
| (*clock->cb)(&clock->timestamp, clock->user_data); |
| |
| /* Report timestamp to caller */ |
| if (ts) |
| ts->u64 = clock->timestamp.u64; |
| |
| /* Increment timestamp */ |
| clock->timestamp.u64 += clock->samples_per_frame; |
| |
| /* Calculate next tick */ |
| clock_calc_next_tick(clock, &now); |
| |
| /* Done */ |
| return PJ_TRUE; |
| } |
| |
| |
| /* |
| * Clock thread |
| */ |
| static int clock_thread(void *arg) |
| { |
| pj_timestamp now; |
| pjmedia_clock *clock = (pjmedia_clock*) arg; |
| |
| /* Set thread priority to maximum unless not wanted. */ |
| if ((clock->options & PJMEDIA_CLOCK_NO_HIGHEST_PRIO) == 0) { |
| int max = pj_thread_get_prio_max(pj_thread_this()); |
| if (max > 0) |
| pj_thread_set_prio(pj_thread_this(), max); |
| } |
| |
| /* Get the first tick */ |
| pj_get_timestamp(&clock->next_tick); |
| clock->next_tick.u64 += clock->interval.u64; |
| |
| |
| while (!clock->quitting) { |
| |
| pj_get_timestamp(&now); |
| |
| /* Wait for the next tick to happen */ |
| if (now.u64 < clock->next_tick.u64) { |
| unsigned msec; |
| msec = pj_elapsed_msec(&now, &clock->next_tick); |
| pj_thread_sleep(msec); |
| } |
| |
| /* Skip if not running */ |
| if (!clock->running) { |
| /* Calculate next tick */ |
| clock_calc_next_tick(clock, &now); |
| continue; |
| } |
| |
| pj_lock_acquire(clock->lock); |
| |
| /* Call callback, if any */ |
| if (clock->cb) |
| (*clock->cb)(&clock->timestamp, clock->user_data); |
| |
| /* Increment timestamp */ |
| clock->timestamp.u64 += clock->samples_per_frame; |
| |
| /* Calculate next tick */ |
| clock_calc_next_tick(clock, &now); |
| |
| pj_lock_release(clock->lock); |
| } |
| |
| return 0; |
| } |
| |
| |
| /* |
| * Destroy the clock. |
| */ |
| PJ_DEF(pj_status_t) pjmedia_clock_destroy(pjmedia_clock *clock) |
| { |
| PJ_ASSERT_RETURN(clock != NULL, PJ_EINVAL); |
| |
| clock->running = PJ_FALSE; |
| clock->quitting = PJ_TRUE; |
| |
| if (clock->thread) { |
| pj_thread_join(clock->thread); |
| pj_thread_destroy(clock->thread); |
| clock->thread = NULL; |
| } |
| |
| if (clock->lock) { |
| pj_lock_destroy(clock->lock); |
| clock->lock = NULL; |
| } |
| |
| return PJ_SUCCESS; |
| } |
| |
| |