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Diffstat (limited to 'src/modules/module-loopback.c')
| -rw-r--r-- | src/modules/module-loopback.c | 1652 |
1 files changed, 1652 insertions, 0 deletions
diff --git a/src/modules/module-loopback.c b/src/modules/module-loopback.c new file mode 100644 index 0000000..871f011 --- /dev/null +++ b/src/modules/module-loopback.c @@ -0,0 +1,1652 @@ +/*** + This file is part of PulseAudio. + + Copyright 2009 Intel Corporation + Contributor: Pierre-Louis Bossart <pierre-louis.bossart@intel.com> + + PulseAudio 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. + + PulseAudio 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 Lesser General Public License + along with PulseAudio; if not, see <http://www.gnu.org/licenses/>. +***/ + +#ifdef HAVE_CONFIG_H +#include <config.h> +#endif + +#include <stdio.h> + +#include <pulse/xmalloc.h> + +#include <pulsecore/sink-input.h> +#include <pulsecore/module.h> +#include <pulsecore/modargs.h> +#include <pulsecore/namereg.h> +#include <pulsecore/log.h> +#include <pulsecore/core-util.h> + +#include <pulse/rtclock.h> +#include <pulse/timeval.h> + +PA_MODULE_AUTHOR("Pierre-Louis Bossart"); +PA_MODULE_DESCRIPTION("Loopback from source to sink"); +PA_MODULE_VERSION(PACKAGE_VERSION); +PA_MODULE_LOAD_ONCE(false); +PA_MODULE_USAGE( + "source=<source to connect to> " + "sink=<sink to connect to> " + "adjust_time=<how often to readjust rates in s> " + "latency_msec=<latency in ms> " + "max_latency_msec=<maximum latency in ms> " + "fast_adjust_threshold_msec=<threshold for fast adjust in ms> " + "format=<sample format> " + "rate=<sample rate> " + "channels=<number of channels> " + "channel_map=<channel map> " + "sink_input_properties=<proplist> " + "source_output_properties=<proplist> " + "source_dont_move=<boolean> " + "sink_dont_move=<boolean> " + "remix=<remix channels?> "); + +#define DEFAULT_LATENCY_MSEC 200 + +#define MEMBLOCKQ_MAXLENGTH (1024*1024*32) + +#define MIN_DEVICE_LATENCY (2.5*PA_USEC_PER_MSEC) + +#define DEFAULT_ADJUST_TIME_USEC (10*PA_USEC_PER_SEC) + +typedef struct loopback_msg loopback_msg; + +struct userdata { + pa_core *core; + pa_module *module; + + loopback_msg *msg; + + pa_sink_input *sink_input; + pa_source_output *source_output; + + pa_asyncmsgq *asyncmsgq; + pa_memblockq *memblockq; + + pa_rtpoll_item *rtpoll_item_read, *rtpoll_item_write; + + pa_time_event *time_event; + + /* Variables used to calculate the average time between + * subsequent calls of adjust_rates() */ + pa_usec_t adjust_time_stamp; + pa_usec_t real_adjust_time; + pa_usec_t real_adjust_time_sum; + + /* Values from command line configuration */ + pa_usec_t latency; + pa_usec_t max_latency; + pa_usec_t adjust_time; + pa_usec_t fast_adjust_threshold; + + /* Latency boundaries and current values */ + pa_usec_t min_source_latency; + pa_usec_t max_source_latency; + pa_usec_t min_sink_latency; + pa_usec_t max_sink_latency; + pa_usec_t configured_sink_latency; + pa_usec_t configured_source_latency; + int64_t source_latency_offset; + int64_t sink_latency_offset; + pa_usec_t minimum_latency; + + /* lower latency limit found by underruns */ + pa_usec_t underrun_latency_limit; + + /* Various counters */ + uint32_t iteration_counter; + uint32_t underrun_counter; + uint32_t adjust_counter; + + bool fixed_alsa_source; + bool source_sink_changed; + + /* Used for sink input and source output snapshots */ + struct { + int64_t send_counter; + int64_t source_latency; + pa_usec_t source_timestamp; + + int64_t recv_counter; + size_t loopback_memblockq_length; + int64_t sink_latency; + pa_usec_t sink_timestamp; + } latency_snapshot; + + /* Input thread variable */ + int64_t send_counter; + + /* Output thread variables */ + struct { + int64_t recv_counter; + pa_usec_t effective_source_latency; + + /* Copied from main thread */ + pa_usec_t minimum_latency; + + /* Various booleans */ + bool in_pop; + bool pop_called; + bool pop_adjust; + bool first_pop_done; + bool push_called; + } output_thread_info; +}; + +struct loopback_msg { + pa_msgobject parent; + struct userdata *userdata; +}; + +PA_DEFINE_PRIVATE_CLASS(loopback_msg, pa_msgobject); +#define LOOPBACK_MSG(o) (loopback_msg_cast(o)) + +static const char* const valid_modargs[] = { + "source", + "sink", + "adjust_time", + "latency_msec", + "max_latency_msec", + "fast_adjust_threshold_msec", + "format", + "rate", + "channels", + "channel_map", + "sink_input_properties", + "source_output_properties", + "source_dont_move", + "sink_dont_move", + "remix", + NULL, +}; + +enum { + SINK_INPUT_MESSAGE_POST = PA_SINK_INPUT_MESSAGE_MAX, + SINK_INPUT_MESSAGE_REWIND, + SINK_INPUT_MESSAGE_LATENCY_SNAPSHOT, + SINK_INPUT_MESSAGE_SOURCE_CHANGED, + SINK_INPUT_MESSAGE_SET_EFFECTIVE_SOURCE_LATENCY, + SINK_INPUT_MESSAGE_UPDATE_MIN_LATENCY, + SINK_INPUT_MESSAGE_FAST_ADJUST, +}; + +enum { + SOURCE_OUTPUT_MESSAGE_LATENCY_SNAPSHOT = PA_SOURCE_OUTPUT_MESSAGE_MAX, +}; + +enum { + LOOPBACK_MESSAGE_SOURCE_LATENCY_RANGE_CHANGED, + LOOPBACK_MESSAGE_SINK_LATENCY_RANGE_CHANGED, + LOOPBACK_MESSAGE_UNDERRUN, +}; + +static void enable_adjust_timer(struct userdata *u, bool enable); + +/* Called from main context */ +static void teardown(struct userdata *u) { + pa_assert(u); + pa_assert_ctl_context(); + + u->adjust_time = 0; + enable_adjust_timer(u, false); + + /* Handling the asyncmsgq between the source output and the sink input + * requires some care. When the source output is unlinked, nothing needs + * to be done for the asyncmsgq, because the source output is the sending + * end. But when the sink input is unlinked, we should ensure that the + * asyncmsgq is emptied, because the messages in the queue hold references + * to the sink input. Also, we need to ensure that new messages won't be + * written to the queue after we have emptied it. + * + * Emptying the queue can be done in the state_change() callback of the + * sink input, when the new state is "unlinked". + * + * Preventing new messages from being written to the queue can be achieved + * by unlinking the source output before unlinking the sink input. There + * are no other writers for that queue, so this is sufficient. */ + + if (u->source_output) { + pa_source_output_unlink(u->source_output); + pa_source_output_unref(u->source_output); + u->source_output = NULL; + } + + if (u->sink_input) { + pa_sink_input_unlink(u->sink_input); + pa_sink_input_unref(u->sink_input); + u->sink_input = NULL; + } +} + +/* rate controller, called from main context + * - maximum deviation from base rate is less than 1% + * - can create audible artifacts by changing the rate too quickly + * - exhibits hunting with USB or Bluetooth sources + */ +static uint32_t rate_controller( + uint32_t base_rate, + pa_usec_t adjust_time, + int32_t latency_difference_usec) { + + uint32_t new_rate; + double min_cycles; + + /* Calculate best rate to correct the current latency offset, limit at + * slightly below 1% difference from base_rate */ + min_cycles = (double)abs(latency_difference_usec) / adjust_time / 0.01 + 1; + new_rate = base_rate * (1.0 + (double)latency_difference_usec / min_cycles / adjust_time); + + return new_rate; +} + +/* Called from main thread. + * It has been a matter of discussion how to correctly calculate the minimum + * latency that module-loopback can deliver with a given source and sink. + * The calculation has been placed in a separate function so that the definition + * can easily be changed. The resulting estimate is not very exact because it + * depends on the reported latency ranges. In cases were the lower bounds of + * source and sink latency are not reported correctly (USB) the result will + * be wrong. */ +static void update_minimum_latency(struct userdata *u, pa_sink *sink, bool print_msg) { + + if (u->underrun_latency_limit) + /* If we already detected a real latency limit because of underruns, use it */ + u->minimum_latency = u->underrun_latency_limit; + + else { + /* Calculate latency limit from latency ranges */ + + u->minimum_latency = u->min_sink_latency; + if (u->fixed_alsa_source) + /* If we are using an alsa source with fixed latency, we will get a wakeup when + * one fragment is filled, and then we empty the source buffer, so the source + * latency never grows much beyond one fragment (assuming that the CPU doesn't + * cause a bottleneck). */ + u->minimum_latency += u->core->default_fragment_size_msec * PA_USEC_PER_MSEC; + + else + /* In all other cases the source will deliver new data at latest after one source latency. + * Make sure there is enough data available that the sink can keep on playing until new + * data is pushed. */ + u->minimum_latency += u->min_source_latency; + + /* Multiply by 1.1 as a safety margin for delays that are proportional to the buffer sizes */ + u->minimum_latency *= 1.1; + + /* Add 1.5 ms as a safety margin for delays not related to the buffer sizes */ + u->minimum_latency += 1.5 * PA_USEC_PER_MSEC; + } + + /* Add the latency offsets */ + if (-(u->sink_latency_offset + u->source_latency_offset) <= (int64_t)u->minimum_latency) + u->minimum_latency += u->sink_latency_offset + u->source_latency_offset; + else + u->minimum_latency = 0; + + /* If the sink is valid, send a message to update the minimum latency to + * the output thread, else set the variable directly */ + if (sink) + pa_asyncmsgq_send(sink->asyncmsgq, PA_MSGOBJECT(u->sink_input), SINK_INPUT_MESSAGE_UPDATE_MIN_LATENCY, NULL, u->minimum_latency, NULL); + else + u->output_thread_info.minimum_latency = u->minimum_latency; + + if (print_msg) { + pa_log_info("Minimum possible end to end latency: %0.2f ms", (double)u->minimum_latency / PA_USEC_PER_MSEC); + if (u->latency < u->minimum_latency) + pa_log_warn("Configured latency of %0.2f ms is smaller than minimum latency, using minimum instead", (double)u->latency / PA_USEC_PER_MSEC); + } +} + +/* Called from main context */ +static void adjust_rates(struct userdata *u) { + size_t buffer; + uint32_t old_rate, base_rate, new_rate, run_hours; + int32_t latency_difference; + pa_usec_t current_buffer_latency, snapshot_delay; + int64_t current_source_sink_latency, current_latency, latency_at_optimum_rate; + pa_usec_t final_latency, now, time_passed; + + pa_assert(u); + pa_assert_ctl_context(); + + /* Runtime and counters since last change of source or sink + * or source/sink latency */ + run_hours = u->iteration_counter * u->real_adjust_time / PA_USEC_PER_SEC / 3600; + u->iteration_counter +=1; + + /* If we are seeing underruns then the latency is too small */ + if (u->underrun_counter > 2) { + pa_usec_t target_latency; + + target_latency = PA_MAX(u->latency, u->minimum_latency) + 5 * PA_USEC_PER_MSEC; + + if (u->max_latency == 0 || target_latency < u->max_latency) { + u->underrun_latency_limit = PA_CLIP_SUB((int64_t)target_latency, u->sink_latency_offset + u->source_latency_offset); + pa_log_warn("Too many underruns, increasing latency to %0.2f ms", (double)target_latency / PA_USEC_PER_MSEC); + } else { + u->underrun_latency_limit = PA_CLIP_SUB((int64_t)u->max_latency, u->sink_latency_offset + u->source_latency_offset); + pa_log_warn("Too many underruns, configured maximum latency of %0.2f ms is reached", (double)u->max_latency / PA_USEC_PER_MSEC); + pa_log_warn("Consider increasing the max_latency_msec"); + } + + update_minimum_latency(u, u->sink_input->sink, false); + u->underrun_counter = 0; + } + + /* Allow one underrun per hour */ + if (u->iteration_counter * u->real_adjust_time / PA_USEC_PER_SEC / 3600 > run_hours) { + u->underrun_counter = PA_CLIP_SUB(u->underrun_counter, 1u); + pa_log_info("Underrun counter: %u", u->underrun_counter); + } + + /* Calculate real adjust time if source or sink did not change and if the system has + * not been suspended. If the time between two calls is more than 5% longer than the + * configured adjust time, we assume that the system has been sleeping and skip the + * calculation for this iteration. */ + now = pa_rtclock_now(); + time_passed = now - u->adjust_time_stamp; + if (!u->source_sink_changed && time_passed < u->adjust_time * 1.05) { + u->adjust_counter++; + u->real_adjust_time_sum += time_passed; + u->real_adjust_time = u->real_adjust_time_sum / u->adjust_counter; + } + u->adjust_time_stamp = now; + + /* Rates and latencies */ + old_rate = u->sink_input->sample_spec.rate; + base_rate = u->source_output->sample_spec.rate; + + buffer = u->latency_snapshot.loopback_memblockq_length; + if (u->latency_snapshot.recv_counter <= u->latency_snapshot.send_counter) + buffer += (size_t) (u->latency_snapshot.send_counter - u->latency_snapshot.recv_counter); + else + buffer = PA_CLIP_SUB(buffer, (size_t) (u->latency_snapshot.recv_counter - u->latency_snapshot.send_counter)); + + current_buffer_latency = pa_bytes_to_usec(buffer, &u->sink_input->sample_spec); + snapshot_delay = u->latency_snapshot.source_timestamp - u->latency_snapshot.sink_timestamp; + current_source_sink_latency = u->latency_snapshot.sink_latency + u->latency_snapshot.source_latency - snapshot_delay; + + /* Current latency */ + current_latency = current_source_sink_latency + current_buffer_latency; + + /* Latency at base rate */ + latency_at_optimum_rate = current_source_sink_latency + current_buffer_latency * old_rate / base_rate; + + final_latency = PA_MAX(u->latency, u->minimum_latency); + latency_difference = (int32_t)(latency_at_optimum_rate - final_latency); + + pa_log_debug("Loopback overall latency is %0.2f ms + %0.2f ms + %0.2f ms = %0.2f ms", + (double) u->latency_snapshot.sink_latency / PA_USEC_PER_MSEC, + (double) current_buffer_latency / PA_USEC_PER_MSEC, + (double) u->latency_snapshot.source_latency / PA_USEC_PER_MSEC, + (double) current_latency / PA_USEC_PER_MSEC); + + pa_log_debug("Loopback latency at base rate is %0.2f ms", (double)latency_at_optimum_rate / PA_USEC_PER_MSEC); + + /* Drop or insert samples if fast_adjust_threshold_msec was specified and the latency difference is too large. */ + if (u->fast_adjust_threshold > 0 && abs(latency_difference) > u->fast_adjust_threshold) { + pa_log_debug ("Latency difference larger than %" PRIu64 " msec, skipping or inserting samples.", u->fast_adjust_threshold / PA_USEC_PER_MSEC); + + pa_asyncmsgq_send(u->sink_input->sink->asyncmsgq, PA_MSGOBJECT(u->sink_input), SINK_INPUT_MESSAGE_FAST_ADJUST, NULL, current_source_sink_latency, NULL); + + /* Skip real adjust time calculation on next iteration. */ + u->source_sink_changed = true; + return; + } + + /* Calculate new rate */ + new_rate = rate_controller(base_rate, u->real_adjust_time, latency_difference); + + u->source_sink_changed = false; + + /* Set rate */ + pa_sink_input_set_rate(u->sink_input, new_rate); + pa_log_debug("[%s] Updated sampling rate to %lu Hz.", u->sink_input->sink->name, (unsigned long) new_rate); +} + +/* Called from main context */ +static void time_callback(pa_mainloop_api *a, pa_time_event *e, const struct timeval *t, void *userdata) { + struct userdata *u = userdata; + + pa_assert(u); + pa_assert(a); + pa_assert(u->time_event == e); + + /* Restart timer right away */ + pa_core_rttime_restart(u->core, u->time_event, pa_rtclock_now() + u->adjust_time); + + /* Get sink and source latency snapshot */ + pa_asyncmsgq_send(u->sink_input->sink->asyncmsgq, PA_MSGOBJECT(u->sink_input), SINK_INPUT_MESSAGE_LATENCY_SNAPSHOT, NULL, 0, NULL); + pa_asyncmsgq_send(u->source_output->source->asyncmsgq, PA_MSGOBJECT(u->source_output), SOURCE_OUTPUT_MESSAGE_LATENCY_SNAPSHOT, NULL, 0, NULL); + + adjust_rates(u); +} + +/* Called from main context + * When source or sink changes, give it a third of a second to settle down, then call adjust_rates for the first time */ +static void enable_adjust_timer(struct userdata *u, bool enable) { + if (enable) { + if (!u->adjust_time) + return; + if (u->time_event) + u->core->mainloop->time_free(u->time_event); + + u->time_event = pa_core_rttime_new(u->core, pa_rtclock_now() + 333 * PA_USEC_PER_MSEC, time_callback, u); + } else { + if (!u->time_event) + return; + + u->core->mainloop->time_free(u->time_event); + u->time_event = NULL; + } +} + +/* Called from main context */ +static void update_adjust_timer(struct userdata *u) { + if (u->sink_input->state == PA_SINK_INPUT_CORKED || u->source_output->state == PA_SOURCE_OUTPUT_CORKED) + enable_adjust_timer(u, false); + else + enable_adjust_timer(u, true); +} + +/* Called from main thread + * Calculates minimum and maximum possible latency for source and sink */ +static void update_latency_boundaries(struct userdata *u, pa_source *source, pa_sink *sink) { + const char *s; + + if (source) { + /* Source latencies */ + u->fixed_alsa_source = false; + if (source->flags & PA_SOURCE_DYNAMIC_LATENCY) + pa_source_get_latency_range(source, &u->min_source_latency, &u->max_source_latency); + else { + u->min_source_latency = pa_source_get_fixed_latency(source); + u->max_source_latency = u->min_source_latency; + if ((s = pa_proplist_gets(source->proplist, PA_PROP_DEVICE_API))) { + if (pa_streq(s, "alsa")) + u->fixed_alsa_source = true; + } + } + /* Source offset */ + u->source_latency_offset = source->port_latency_offset; + + /* Latencies below 2.5 ms cause problems, limit source latency if possible */ + if (u->max_source_latency >= MIN_DEVICE_LATENCY) + u->min_source_latency = PA_MAX(u->min_source_latency, MIN_DEVICE_LATENCY); + else + u->min_source_latency = u->max_source_latency; + } + + if (sink) { + /* Sink latencies */ + if (sink->flags & PA_SINK_DYNAMIC_LATENCY) + pa_sink_get_latency_range(sink, &u->min_sink_latency, &u->max_sink_latency); + else { + u->min_sink_latency = pa_sink_get_fixed_latency(sink); + u->max_sink_latency = u->min_sink_latency; + } + /* Sink offset */ + u->sink_latency_offset = sink->port_latency_offset; + + /* Latencies below 2.5 ms cause problems, limit sink latency if possible */ + if (u->max_sink_latency >= MIN_DEVICE_LATENCY) + u->min_sink_latency = PA_MAX(u->min_sink_latency, MIN_DEVICE_LATENCY); + else + u->min_sink_latency = u->max_sink_latency; + } + + update_minimum_latency(u, sink, true); +} + +/* Called from output context + * Sets the memblockq to the configured latency corrected by latency_offset_usec */ +static void memblockq_adjust(struct userdata *u, int64_t latency_offset_usec, bool allow_push) { + size_t current_memblockq_length, requested_memblockq_length, buffer_correction; + int64_t requested_buffer_latency; + pa_usec_t final_latency, requested_sink_latency; + + final_latency = PA_MAX(u->latency, u->output_thread_info.minimum_latency); + + /* If source or sink have some large negative latency offset, we might want to + * hold more than final_latency in the memblockq */ + requested_buffer_latency = (int64_t)final_latency - latency_offset_usec; + + /* Keep at least one sink latency in the queue to make sure that the sink + * never underruns initially */ + requested_sink_latency = pa_sink_get_requested_latency_within_thread(u->sink_input->sink); + if (requested_buffer_latency < (int64_t)requested_sink_latency) + requested_buffer_latency = requested_sink_latency; + + requested_memblockq_length = pa_usec_to_bytes(requested_buffer_latency, &u->sink_input->sample_spec); + current_memblockq_length = pa_memblockq_get_length(u->memblockq); + + if (current_memblockq_length > requested_memblockq_length) { + /* Drop audio from queue */ + buffer_correction = current_memblockq_length - requested_memblockq_length; + pa_log_info("Dropping %" PRIu64 " usec of audio from queue", pa_bytes_to_usec(buffer_correction, &u->sink_input->sample_spec)); + pa_memblockq_drop(u->memblockq, buffer_correction); + + } else if (current_memblockq_length < requested_memblockq_length && allow_push) { + /* Add silence to queue */ + buffer_correction = requested_memblockq_length - current_memblockq_length; + pa_log_info("Adding %" PRIu64 " usec of silence to queue", pa_bytes_to_usec(buffer_correction, &u->sink_input->sample_spec)); + pa_memblockq_seek(u->memblockq, (int64_t)buffer_correction, PA_SEEK_RELATIVE, true); + } +} + +/* Called from input thread context */ +static void source_output_push_cb(pa_source_output *o, const pa_memchunk *chunk) { + struct userdata *u; + pa_usec_t push_time; + int64_t current_source_latency; + + pa_source_output_assert_ref(o); + pa_source_output_assert_io_context(o); + pa_assert_se(u = o->userdata); + + /* Send current source latency and timestamp with the message */ + push_time = pa_rtclock_now(); + current_source_latency = pa_source_get_latency_within_thread(u->source_output->source, true); + + pa_asyncmsgq_post(u->asyncmsgq, PA_MSGOBJECT(u->sink_input), SINK_INPUT_MESSAGE_POST, PA_INT_TO_PTR(current_source_latency), push_time, chunk, NULL); + u->send_counter += (int64_t) chunk->length; +} + +/* Called from input thread context */ +static void source_output_process_rewind_cb(pa_source_output *o, size_t nbytes) { + struct userdata *u; + + pa_source_output_assert_ref(o); + pa_source_output_assert_io_context(o); + pa_assert_se(u = o->userdata); + + pa_asyncmsgq_post(u->asyncmsgq, PA_MSGOBJECT(u->sink_input), SINK_INPUT_MESSAGE_REWIND, NULL, (int64_t) nbytes, NULL, NULL); + u->send_counter -= (int64_t) nbytes; +} + +/* Called from input thread context */ +static int source_output_process_msg_cb(pa_msgobject *obj, int code, void *data, int64_t offset, pa_memchunk *chunk) { + struct userdata *u = PA_SOURCE_OUTPUT(obj)->userdata; + + switch (code) { + + case SOURCE_OUTPUT_MESSAGE_LATENCY_SNAPSHOT: { + size_t length; + + length = pa_memblockq_get_length(u->source_output->thread_info.delay_memblockq); + + u->latency_snapshot.send_counter = u->send_counter; + /* Add content of delay memblockq to the source latency */ + u->latency_snapshot.source_latency = pa_source_get_latency_within_thread(u->source_output->source, true) + + pa_bytes_to_usec(length, &u->source_output->source->sample_spec); + u->latency_snapshot.source_timestamp = pa_rtclock_now(); + + return 0; + } + } + + return pa_source_output_process_msg(obj, code, data, offset, chunk); +} + +/* Called from main thread. + * Get current effective latency of the source. If the source is in use with + * smaller latency than the configured latency, it will continue running with + * the smaller value when the source output is switched to the source. */ +static void update_effective_source_latency(struct userdata *u, pa_source *source, pa_sink *sink) { + pa_usec_t effective_source_latency; + + effective_source_latency = u->configured_source_latency; + + if (source) { + effective_source_latency = pa_source_get_requested_latency(source); + if (effective_source_latency == 0 || effective_source_latency > u->configured_source_latency) + effective_source_latency = u->configured_source_latency; + } + + /* If the sink is valid, send a message to the output thread, else set the variable directly */ + if (sink) + pa_asyncmsgq_send(sink->asyncmsgq, PA_MSGOBJECT(u->sink_input), SINK_INPUT_MESSAGE_SET_EFFECTIVE_SOURCE_LATENCY, NULL, (int64_t)effective_source_latency, NULL); + else + u->output_thread_info.effective_source_latency = effective_source_latency; +} + +/* Called from main thread. + * Set source output latency to one third of the overall latency if possible. + * The choice of one third is rather arbitrary somewhere between the minimum + * possible latency which would cause a lot of CPU load and half the configured + * latency which would quickly lead to underruns */ +static void set_source_output_latency(struct userdata *u, pa_source *source) { + pa_usec_t latency, requested_latency; + + requested_latency = u->latency / 3; + + /* Normally we try to configure sink and source latency equally. If the + * sink latency cannot match the requested source latency try to set the + * source latency to a smaller value to avoid underruns */ + if (u->min_sink_latency > requested_latency) { + latency = PA_MAX(u->latency, u->minimum_latency); + requested_latency = (latency - u->min_sink_latency) / 2; + } + + latency = PA_CLAMP(requested_latency , u->min_source_latency, u->max_source_latency); + u->configured_source_latency = pa_source_output_set_requested_latency(u->source_output, latency); + if (u->configured_source_latency != requested_latency) + pa_log_warn("Cannot set requested source latency of %0.2f ms, adjusting to %0.2f ms", (double)requested_latency / PA_USEC_PER_MSEC, (double)u->configured_source_latency / PA_USEC_PER_MSEC); +} + +/* Called from input thread context */ +static void source_output_attach_cb(pa_source_output *o) { + struct userdata *u; + + pa_source_output_assert_ref(o); + pa_source_output_assert_io_context(o); + pa_assert_se(u = o->userdata); + + u->rtpoll_item_write = pa_rtpoll_item_new_asyncmsgq_write( + o->source->thread_info.rtpoll, + PA_RTPOLL_LATE, + u->asyncmsgq); +} + +/* Called from input thread context */ +static void source_output_detach_cb(pa_source_output *o) { + struct userdata *u; + + pa_source_output_assert_ref(o); + pa_source_output_assert_io_context(o); + pa_assert_se(u = o->userdata); + + if (u->rtpoll_item_write) { + pa_rtpoll_item_free(u->rtpoll_item_write); + u->rtpoll_item_write = NULL; + } +} + +/* Called from main thread */ +static void source_output_kill_cb(pa_source_output *o) { + struct userdata *u; + + pa_source_output_assert_ref(o); + pa_assert_ctl_context(); + pa_assert_se(u = o->userdata); + + teardown(u); + pa_module_unload_request(u->module, true); +} + +/* Called from main thread */ +static bool source_output_may_move_to_cb(pa_source_output *o, pa_source *dest) { + struct userdata *u; + + pa_source_output_assert_ref(o); + pa_assert_ctl_context(); + pa_assert_se(u = o->userdata); + + if (!u->sink_input || !u->sink_input->sink) + return true; + + return dest != u->sink_input->sink->monitor_source; +} + +/* Called from main thread */ +static void source_output_moving_cb(pa_source_output *o, pa_source *dest) { + struct userdata *u; + char *input_description; + const char *n; + + if (!dest) + return; + + pa_source_output_assert_ref(o); + pa_assert_ctl_context(); + pa_assert_se(u = o->userdata); + + input_description = pa_sprintf_malloc("Loopback of %s", + pa_strnull(pa_proplist_gets(dest->proplist, PA_PROP_DEVICE_DESCRIPTION))); + pa_sink_input_set_property(u->sink_input, PA_PROP_MEDIA_NAME, input_description); + pa_xfree(input_description); + + if ((n = pa_proplist_gets(dest->proplist, PA_PROP_DEVICE_ICON_NAME))) + pa_sink_input_set_property(u->sink_input, PA_PROP_DEVICE_ICON_NAME, n); + + /* Set latency and calculate latency limits */ + u->underrun_latency_limit = 0; + update_latency_boundaries(u, dest, u->sink_input->sink); + set_source_output_latency(u, dest); + update_effective_source_latency(u, dest, u->sink_input->sink); + + /* Uncork the sink input unless the destination is suspended for other + * reasons than idle. */ + if (dest->state == PA_SOURCE_SUSPENDED) + pa_sink_input_cork(u->sink_input, (dest->suspend_cause != PA_SUSPEND_IDLE)); + else + pa_sink_input_cork(u->sink_input, false); + + update_adjust_timer(u); + + /* Reset counters */ + u->iteration_counter = 0; + u->underrun_counter = 0; + + u->source_sink_changed = true; + + /* Send a mesage to the output thread that the source has changed. + * If the sink is invalid here during a profile switching situation + * we can safely set push_called to false directly. */ + if (u->sink_input->sink) + pa_asyncmsgq_send(u->sink_input->sink->asyncmsgq, PA_MSGOBJECT(u->sink_input), SINK_INPUT_MESSAGE_SOURCE_CHANGED, NULL, 0, NULL); + else + u->output_thread_info.push_called = false; + + /* The sampling rate may be far away from the default rate if we are still + * recovering from a previous source or sink change, so reset rate to + * default before moving the source. */ + pa_sink_input_set_rate(u->sink_input, u->source_output->sample_spec.rate); +} + +/* Called from main thread */ +static void source_output_suspend_cb(pa_source_output *o, pa_source_state_t old_state, pa_suspend_cause_t old_suspend_cause) { + struct userdata *u; + bool suspended; + + pa_source_output_assert_ref(o); + pa_assert_ctl_context(); + pa_assert_se(u = o->userdata); + + /* State has not changed, nothing to do */ + if (old_state == o->source->state) + return; + + suspended = (o->source->state == PA_SOURCE_SUSPENDED); + + /* If the source has been suspended, we need to handle this like + * a source change when the source is resumed */ + if (suspended) { + if (u->sink_input->sink) + pa_asyncmsgq_send(u->sink_input->sink->asyncmsgq, PA_MSGOBJECT(u->sink_input), SINK_INPUT_MESSAGE_SOURCE_CHANGED, NULL, 0, NULL); + else + u->output_thread_info.push_called = false; + + } else + /* Get effective source latency on unsuspend */ + update_effective_source_latency(u, u->source_output->source, u->sink_input->sink); + + pa_sink_input_cork(u->sink_input, suspended); + + update_adjust_timer(u); +} + +/* Called from input thread context */ +static void update_source_latency_range_cb(pa_source_output *i) { + struct userdata *u; + + pa_source_output_assert_ref(i); + pa_source_output_assert_io_context(i); + pa_assert_se(u = i->userdata); + + /* Source latency may have changed */ + pa_asyncmsgq_post(pa_thread_mq_get()->outq, PA_MSGOBJECT(u->msg), LOOPBACK_MESSAGE_SOURCE_LATENCY_RANGE_CHANGED, NULL, 0, NULL, NULL); +} + +/* Called from output thread context */ +static int sink_input_pop_cb(pa_sink_input *i, size_t nbytes, pa_memchunk *chunk) { + struct userdata *u; + + pa_sink_input_assert_ref(i); + pa_sink_input_assert_io_context(i); + pa_assert_se(u = i->userdata); + pa_assert(chunk); + + /* It seems necessary to handle outstanding push messages here, though it is not clear + * why. Removing this part leads to underruns when low latencies are configured. */ + u->output_thread_info.in_pop = true; + while (pa_asyncmsgq_process_one(u->asyncmsgq) > 0) + ; + u->output_thread_info.in_pop = false; + + /* While pop has not been called, latency adjustments in SINK_INPUT_MESSAGE_POST are + * enabled. Disable them on second pop and enable the final adjustment during the + * next push. The adjustment must be done on the next push, because there is no way + * to retrieve the source latency here. We are waiting for the second pop, because + * the first pop may be called before the sink is actually started. */ + if (!u->output_thread_info.pop_called && u->output_thread_info.first_pop_done) { + u->output_thread_info.pop_adjust = true; + u->output_thread_info.pop_called = true; + } + u->output_thread_info.first_pop_done = true; + + if (pa_memblockq_peek(u->memblockq, chunk) < 0) { + pa_log_info("Could not peek into queue"); + return -1; + } + + chunk->length = PA_MIN(chunk->length, nbytes); + pa_memblockq_drop(u->memblockq, chunk->length); + + /* Adjust the memblockq to ensure that there is + * enough data in the queue to avoid underruns. */ + if (!u->output_thread_info.push_called) + memblockq_adjust(u, 0, true); + + return 0; +} + +/* Called from output thread context */ +static void sink_input_process_rewind_cb(pa_sink_input *i, size_t nbytes) { + struct userdata *u; + + pa_sink_input_assert_ref(i); + pa_sink_input_assert_io_context(i); + pa_assert_se(u = i->userdata); + + pa_memblockq_rewind(u->memblockq, nbytes); +} + +/* Called from output thread context */ +static int sink_input_process_msg_cb(pa_msgobject *obj, int code, void *data, int64_t offset, pa_memchunk *chunk) { + struct userdata *u = PA_SINK_INPUT(obj)->userdata; + + pa_sink_input_assert_io_context(u->sink_input); + + switch (code) { + + case PA_SINK_INPUT_MESSAGE_GET_LATENCY: { + pa_usec_t *r = data; + + *r = pa_bytes_to_usec(pa_memblockq_get_length(u->memblockq), &u->sink_input->sample_spec); + + /* Fall through, the default handler will add in the extra + * latency added by the resampler */ + break; + } + + case SINK_INPUT_MESSAGE_POST: + + pa_memblockq_push_align(u->memblockq, chunk); + + /* If push has not been called yet, latency adjustments in sink_input_pop_cb() + * are enabled. Disable them on first push and correct the memblockq. If pop + * has not been called yet, wait until the pop_cb() requests the adjustment */ + if (u->output_thread_info.pop_called && (!u->output_thread_info.push_called || u->output_thread_info.pop_adjust)) { + int64_t time_delta; + + /* This is the source latency at the time push was called */ + time_delta = PA_PTR_TO_INT(data); + /* Add the time between push and post */ + time_delta += pa_rtclock_now() - (pa_usec_t) offset; + /* Add the sink latency */ + time_delta += pa_sink_get_latency_within_thread(u->sink_input->sink, true); + + /* The source latency report includes the audio in the chunk, + * but since we already pushed the chunk to the memblockq, we need + * to subtract the chunk size from the source latency so that it + * won't be counted towards both the memblockq latency and the + * source latency. + * + * Sometimes the alsa source reports way too low latency (might + * be a bug in the alsa source code). This seems to happen when + * there's an overrun. As an attempt to detect overruns, we + * check if the chunk size is larger than the configured source + * latency. If so, we assume that the source should have pushed + * a chunk whose size equals the configured latency, so we + * modify time_delta only by that amount, which makes + * memblockq_adjust() drop more data than it would otherwise. + * This seems to work quite well, but it's possible that the + * next push also contains too much data, and in that case the + * resulting latency will be wrong. */ + if (pa_bytes_to_usec(chunk->length, &u->sink_input->sample_spec) > u->output_thread_info.effective_source_latency) + time_delta -= (int64_t)u->output_thread_info.effective_source_latency; + else + time_delta -= (int64_t)pa_bytes_to_usec(chunk->length, &u->sink_input->sample_spec); + + /* FIXME: We allow pushing silence here to fix up the latency. This + * might lead to a gap in the stream */ + memblockq_adjust(u, time_delta, true); + + u->output_thread_info.pop_adjust = false; + u->output_thread_info.push_called = true; + } + + /* If pop has not been called yet, make sure the latency does not grow too much. + * Don't push any silence here, because we already have new data in the queue */ + if (!u->output_thread_info.pop_called) + memblockq_adjust(u, 0, false); + + /* Is this the end of an underrun? Then let's start things + * right-away */ + if (u->sink_input->sink->thread_info.state != PA_SINK_SUSPENDED && + u->sink_input->thread_info.underrun_for > 0 && + pa_memblockq_is_readable(u->memblockq)) { + + pa_asyncmsgq_post(pa_thread_mq_get()->outq, PA_MSGOBJECT(u->msg), LOOPBACK_MESSAGE_UNDERRUN, NULL, 0, NULL, NULL); + /* If called from within the pop callback skip the rewind */ + if (!u->output_thread_info.in_pop) { + pa_log_debug("Requesting rewind due to end of underrun."); + pa_sink_input_request_rewind(u->sink_input, + (size_t) (u->sink_input->thread_info.underrun_for == (size_t) -1 ? 0 : u->sink_input->thread_info.underrun_for), + false, true, false); + } + } + + u->output_thread_info.recv_counter += (int64_t) chunk->length; + + return 0; + + case SINK_INPUT_MESSAGE_REWIND: + + /* Do not try to rewind if no data was pushed yet */ + if (u->output_thread_info.push_called) + pa_memblockq_seek(u->memblockq, -offset, PA_SEEK_RELATIVE, true); + + u->output_thread_info.recv_counter -= offset; + + return 0; + + case SINK_INPUT_MESSAGE_LATENCY_SNAPSHOT: { + size_t length; + + length = pa_memblockq_get_length(u->sink_input->thread_info.render_memblockq); + + u->latency_snapshot.recv_counter = u->output_thread_info.recv_counter; + u->latency_snapshot.loopback_memblockq_length = pa_memblockq_get_length(u->memblockq); + /* Add content of render memblockq to sink latency */ + u->latency_snapshot.sink_latency = pa_sink_get_latency_within_thread(u->sink_input->sink, true) + + pa_bytes_to_usec(length, &u->sink_input->sink->sample_spec); + u->latency_snapshot.sink_timestamp = pa_rtclock_now(); + + return 0; + } + + case SINK_INPUT_MESSAGE_SOURCE_CHANGED: + + u->output_thread_info.push_called = false; + + return 0; + + case SINK_INPUT_MESSAGE_SET_EFFECTIVE_SOURCE_LATENCY: + + u->output_thread_info.effective_source_latency = (pa_usec_t)offset; + + return 0; + + case SINK_INPUT_MESSAGE_UPDATE_MIN_LATENCY: + + u->output_thread_info.minimum_latency = (pa_usec_t)offset; + + return 0; + + case SINK_INPUT_MESSAGE_FAST_ADJUST: + + memblockq_adjust(u, offset, true); + + return 0; + } + + return pa_sink_input_process_msg(obj, code, data, offset, chunk); +} +/* Called from main thread. + * Set sink input latency to one third of the overall latency if possible. + * The choice of one third is rather arbitrary somewhere between the minimum + * possible latency which would cause a lot of CPU load and half the configured + * latency which would quickly lead to underruns. */ +static void set_sink_input_latency(struct userdata *u, pa_sink *sink) { + pa_usec_t latency, requested_latency; + + requested_latency = u->latency / 3; + + /* Normally we try to configure sink and source latency equally. If the + * source latency cannot match the requested sink latency try to set the + * sink latency to a smaller value to avoid underruns */ + if (u->min_source_latency > requested_latency) { + latency = PA_MAX(u->latency, u->minimum_latency); + requested_latency = (latency - u->min_source_latency) / 2; + } + + latency = PA_CLAMP(requested_latency , u->min_sink_latency, u->max_sink_latency); + u->configured_sink_latency = pa_sink_input_set_requested_latency(u->sink_input, latency); + if (u->configured_sink_latency != requested_latency) + pa_log_warn("Cannot set requested sink latency of %0.2f ms, adjusting to %0.2f ms", (double)requested_latency / PA_USEC_PER_MSEC, (double)u->configured_sink_latency / PA_USEC_PER_MSEC); +} + +/* Called from output thread context */ +static void sink_input_attach_cb(pa_sink_input *i) { + struct userdata *u; + + pa_sink_input_assert_ref(i); + pa_sink_input_assert_io_context(i); + pa_assert_se(u = i->userdata); + + u->rtpoll_item_read = pa_rtpoll_item_new_asyncmsgq_read( + i->sink->thread_info.rtpoll, + PA_RTPOLL_LATE, + u->asyncmsgq); + + pa_memblockq_set_prebuf(u->memblockq, pa_sink_input_get_max_request(i)*2); + pa_memblockq_set_maxrewind(u->memblockq, pa_sink_input_get_max_rewind(i)); +} + +/* Called from output thread context */ +static void sink_input_detach_cb(pa_sink_input *i) { + struct userdata *u; + + pa_sink_input_assert_ref(i); + pa_sink_input_assert_io_context(i); + pa_assert_se(u = i->userdata); + + if (u->rtpoll_item_read) { + pa_rtpoll_item_free(u->rtpoll_item_read); + u->rtpoll_item_read = NULL; + } +} + +/* Called from output thread context */ +static void sink_input_update_max_rewind_cb(pa_sink_input *i, size_t nbytes) { + struct userdata *u; + + pa_sink_input_assert_ref(i); + pa_sink_input_assert_io_context(i); + pa_assert_se(u = i->userdata); + + pa_memblockq_set_maxrewind(u->memblockq, nbytes); +} + +/* Called from output thread context */ +static void sink_input_update_max_request_cb(pa_sink_input *i, size_t nbytes) { + struct userdata *u; + + pa_sink_input_assert_ref(i); + pa_sink_input_assert_io_context(i); + pa_assert_se(u = i->userdata); + + pa_memblockq_set_prebuf(u->memblockq, nbytes*2); + pa_log_info("Max request changed"); +} + +/* Called from main thread */ +static void sink_input_kill_cb(pa_sink_input *i) { + struct userdata *u; + + pa_sink_input_assert_ref(i); + pa_assert_ctl_context(); + pa_assert_se(u = i->userdata); + + teardown(u); + pa_module_unload_request(u->module, true); +} + +/* Called from the output thread context */ +static void sink_input_state_change_cb(pa_sink_input *i, pa_sink_input_state_t state) { + struct userdata *u; + + pa_sink_input_assert_ref(i); + pa_assert_se(u = i->userdata); + + if (state == PA_SINK_INPUT_UNLINKED) + pa_asyncmsgq_flush(u->asyncmsgq, false); +} + +/* Called from main thread */ +static void sink_input_moving_cb(pa_sink_input *i, pa_sink *dest) { + struct userdata *u; + char *output_description; + const char *n; + + if (!dest) + return; + + pa_sink_input_assert_ref(i); + pa_assert_ctl_context(); + pa_assert_se(u = i->userdata); + + output_description = pa_sprintf_malloc("Loopback to %s", + pa_strnull(pa_proplist_gets(dest->proplist, PA_PROP_DEVICE_DESCRIPTION))); + pa_source_output_set_property(u->source_output, PA_PROP_MEDIA_NAME, output_description); + pa_xfree(output_description); + + if ((n = pa_proplist_gets(dest->proplist, PA_PROP_DEVICE_ICON_NAME))) + pa_source_output_set_property(u->source_output, PA_PROP_MEDIA_ICON_NAME, n); + + /* Set latency and calculate latency limits */ + u->underrun_latency_limit = 0; + update_latency_boundaries(u, NULL, dest); + set_sink_input_latency(u, dest); + update_effective_source_latency(u, u->source_output->source, dest); + + /* Uncork the source output unless the destination is suspended for other + * reasons than idle */ + if (dest->state == PA_SINK_SUSPENDED) + pa_source_output_cork(u->source_output, (dest->suspend_cause != PA_SUSPEND_IDLE)); + else + pa_source_output_cork(u->source_output, false); + + update_adjust_timer(u); + + /* Reset counters */ + u->iteration_counter = 0; + u->underrun_counter = 0; + + u->source_sink_changed = true; + + u->output_thread_info.pop_called = false; + u->output_thread_info.first_pop_done = false; + + /* Sample rate may be far away from the default rate if we are still + * recovering from a previous source or sink change, so reset rate to + * default before moving the sink. */ + pa_sink_input_set_rate(u->sink_input, u->source_output->sample_spec.rate); +} + +/* Called from main thread */ +static bool sink_input_may_move_to_cb(pa_sink_input *i, pa_sink *dest) { + struct userdata *u; + + pa_sink_input_assert_ref(i); + pa_assert_ctl_context(); + pa_assert_se(u = i->userdata); + + if (!u->source_output || !u->source_output->source) + return true; + + return dest != u->source_output->source->monitor_of; +} + +/* Called from main thread */ +static void sink_input_suspend_cb(pa_sink_input *i, pa_sink_state_t old_state, pa_suspend_cause_t old_suspend_cause) { + struct userdata *u; + bool suspended; + + pa_sink_input_assert_ref(i); + pa_assert_ctl_context(); + pa_assert_se(u = i->userdata); + + /* State has not changed, nothing to do */ + if (old_state == i->sink->state) + return; + + suspended = (i->sink->state == PA_SINK_SUSPENDED); + + /* If the sink has been suspended, we need to handle this like + * a sink change when the sink is resumed. Because the sink + * is suspended, we can set the variables directly. */ + if (suspended) { + u->output_thread_info.pop_called = false; + u->output_thread_info.first_pop_done = false; + + } else + /* Set effective source latency on unsuspend */ + update_effective_source_latency(u, u->source_output->source, u->sink_input->sink); + + pa_source_output_cork(u->source_output, suspended); + + update_adjust_timer(u); +} + +/* Called from output thread context */ +static void update_sink_latency_range_cb(pa_sink_input *i) { + struct userdata *u; + + pa_sink_input_assert_ref(i); + pa_sink_input_assert_io_context(i); + pa_assert_se(u = i->userdata); + + /* Sink latency may have changed */ + pa_asyncmsgq_post(pa_thread_mq_get()->outq, PA_MSGOBJECT(u->msg), LOOPBACK_MESSAGE_SINK_LATENCY_RANGE_CHANGED, NULL, 0, NULL, NULL); +} + +/* Called from main context */ +static int loopback_process_msg_cb(pa_msgobject *o, int code, void *userdata, int64_t offset, pa_memchunk *chunk) { + struct loopback_msg *msg; + struct userdata *u; + pa_usec_t current_latency; + + pa_assert(o); + pa_assert_ctl_context(); + + msg = LOOPBACK_MSG(o); + pa_assert_se(u = msg->userdata); + + switch (code) { + + case LOOPBACK_MESSAGE_SOURCE_LATENCY_RANGE_CHANGED: + + update_effective_source_latency(u, u->source_output->source, u->sink_input->sink); + current_latency = pa_source_get_requested_latency(u->source_output->source); + if (current_latency > u->configured_source_latency) { + /* The minimum latency has changed to a value larger than the configured latency, so + * the source latency has been increased. The case that the minimum latency changes + * back to a smaller value is not handled because this never happens with the current + * source implementations. */ + pa_log_warn("Source minimum latency increased to %0.2f ms", (double)current_latency / PA_USEC_PER_MSEC); + u->configured_source_latency = current_latency; + update_latency_boundaries(u, u->source_output->source, u->sink_input->sink); + /* We re-start counting when the latency has changed */ + u->iteration_counter = 0; + u->underrun_counter = 0; + } + + return 0; + + case LOOPBACK_MESSAGE_SINK_LATENCY_RANGE_CHANGED: + + current_latency = pa_sink_get_requested_latency(u->sink_input->sink); + if (current_latency > u->configured_sink_latency) { + /* The minimum latency has changed to a value larger than the configured latency, so + * the sink latency has been increased. The case that the minimum latency changes back + * to a smaller value is not handled because this never happens with the current sink + * implementations. */ + pa_log_warn("Sink minimum latency increased to %0.2f ms", (double)current_latency / PA_USEC_PER_MSEC); + u->configured_sink_latency = current_latency; + update_latency_boundaries(u, u->source_output->source, u->sink_input->sink); + /* We re-start counting when the latency has changed */ + u->iteration_counter = 0; + u->underrun_counter = 0; + } + + return 0; + + case LOOPBACK_MESSAGE_UNDERRUN: + + u->underrun_counter++; + pa_log_debug("Underrun detected, counter incremented to %u", u->underrun_counter); + + return 0; + + } + + return 0; +} + +static pa_hook_result_t sink_port_latency_offset_changed_cb(pa_core *core, pa_sink *sink, struct userdata *u) { + + if (sink != u->sink_input->sink) + return PA_HOOK_OK; + + u->sink_latency_offset = sink->port_latency_offset; + update_minimum_latency(u, sink, true); + + return PA_HOOK_OK; +} + +static pa_hook_result_t source_port_latency_offset_changed_cb(pa_core *core, pa_source *source, struct userdata *u) { + + if (source != u->source_output->source) + return PA_HOOK_OK; + + u->source_latency_offset = source->port_latency_offset; + update_minimum_latency(u, u->sink_input->sink, true); + + return PA_HOOK_OK; +} + +int pa__init(pa_module *m) { + pa_modargs *ma = NULL; + struct userdata *u; + pa_sink *sink = NULL; + pa_sink_input_new_data sink_input_data; + bool sink_dont_move; + pa_source *source = NULL; + pa_source_output_new_data source_output_data; + bool source_dont_move; + uint32_t latency_msec; + uint32_t max_latency_msec; + uint32_t fast_adjust_threshold; + pa_sample_spec ss; + pa_channel_map map; + bool format_set = false; + bool rate_set = false; + bool channels_set = false; + pa_memchunk silence; + uint32_t adjust_time_sec; + const char *n; + bool remix = true; + + pa_assert(m); + + if (!(ma = pa_modargs_new(m->argument, valid_modargs))) { + pa_log("Failed to parse module arguments"); + goto fail; + } + + n = pa_modargs_get_value(ma, "source", NULL); + if (n && !(source = pa_namereg_get(m->core, n, PA_NAMEREG_SOURCE))) { + pa_log("No such source."); + goto fail; + } + + n = pa_modargs_get_value(ma, "sink", NULL); + if (n && !(sink = pa_namereg_get(m->core, n, PA_NAMEREG_SINK))) { + pa_log("No such sink."); + goto fail; + } + + if (pa_modargs_get_value_boolean(ma, "remix", &remix) < 0) { + pa_log("Invalid boolean remix parameter"); + goto fail; + } + + if (source) { + ss = source->sample_spec; + map = source->channel_map; + format_set = true; + rate_set = true; + channels_set = true; + } else if (sink) { + ss = sink->sample_spec; + map = sink->channel_map; + format_set = true; + rate_set = true; + channels_set = true; + } else { + /* FIXME: Dummy stream format, needed because pa_sink_input_new() + * requires valid sample spec and channel map even when all the FIX_* + * stream flags are specified. pa_sink_input_new() should be changed + * to ignore the sample spec and channel map when the FIX_* flags are + * present. */ + ss.format = PA_SAMPLE_U8; + ss.rate = 8000; + ss.channels = 1; + map.channels = 1; + map.map[0] = PA_CHANNEL_POSITION_MONO; + } + + if (pa_modargs_get_sample_spec_and_channel_map(ma, &ss, &map, PA_CHANNEL_MAP_DEFAULT) < 0) { + pa_log("Invalid sample format specification or channel map"); + goto fail; + } + + if (ss.rate < 4000 || ss.rate > PA_RATE_MAX) { + pa_log("Invalid rate specification, valid range is 4000 Hz to %i Hz", PA_RATE_MAX); + goto fail; + } + + if (pa_modargs_get_value(ma, "format", NULL)) + format_set = true; + + if (pa_modargs_get_value(ma, "rate", NULL)) + rate_set = true; + + if (pa_modargs_get_value(ma, "channels", NULL) || pa_modargs_get_value(ma, "channel_map", NULL)) + channels_set = true; + + latency_msec = DEFAULT_LATENCY_MSEC; + if (pa_modargs_get_value_u32(ma, "latency_msec", &latency_msec) < 0 || latency_msec < 1 || latency_msec > 30000) { + pa_log("Invalid latency specification"); + goto fail; + } + + fast_adjust_threshold = 0; + if (pa_modargs_get_value_u32(ma, "fast_adjust_threshold_msec", &fast_adjust_threshold) < 0 || (fast_adjust_threshold != 0 && fast_adjust_threshold < 100)) { + pa_log("Invalid fast adjust threshold specification"); + goto fail; + } + + max_latency_msec = 0; + if (pa_modargs_get_value_u32(ma, "max_latency_msec", &max_latency_msec) < 0) { + pa_log("Invalid maximum latency specification"); + goto fail; + } + + if (max_latency_msec > 0 && max_latency_msec < latency_msec) { + pa_log_warn("Configured maximum latency is smaller than latency, using latency instead"); + max_latency_msec = latency_msec; + } + + m->userdata = u = pa_xnew0(struct userdata, 1); + u->core = m->core; + u->module = m; + u->latency = (pa_usec_t) latency_msec * PA_USEC_PER_MSEC; + u->max_latency = (pa_usec_t) max_latency_msec * PA_USEC_PER_MSEC; + u->output_thread_info.pop_called = false; + u->output_thread_info.pop_adjust = false; + u->output_thread_info.push_called = false; + u->iteration_counter = 0; + u->underrun_counter = 0; + u->underrun_latency_limit = 0; + u->source_sink_changed = true; + u->real_adjust_time_sum = 0; + u->adjust_counter = 0; + u->fast_adjust_threshold = fast_adjust_threshold * PA_USEC_PER_MSEC; + + adjust_time_sec = DEFAULT_ADJUST_TIME_USEC / PA_USEC_PER_SEC; + if (pa_modargs_get_value_u32(ma, "adjust_time", &adjust_time_sec) < 0) { + pa_log("Failed to parse adjust_time value"); + goto fail; + } + + if (adjust_time_sec != DEFAULT_ADJUST_TIME_USEC / PA_USEC_PER_SEC) + u->adjust_time = adjust_time_sec * PA_USEC_PER_SEC; + else + u->adjust_time = DEFAULT_ADJUST_TIME_USEC; + + u->real_adjust_time = u->adjust_time; + + pa_source_output_new_data_init(&source_output_data); + source_output_data.driver = __FILE__; + source_output_data.module = m; + if (source) + pa_source_output_new_data_set_source(&source_output_data, source, false, true); + + if (pa_modargs_get_proplist(ma, "source_output_properties", source_output_data.proplist, PA_UPDATE_REPLACE) < 0) { + pa_log("Failed to parse the source_output_properties value."); + pa_source_output_new_data_done(&source_output_data); + goto fail; + } + + if (!pa_proplist_contains(source_output_data.proplist, PA_PROP_MEDIA_ROLE)) + pa_proplist_sets(source_output_data.proplist, PA_PROP_MEDIA_ROLE, "abstract"); + + pa_source_output_new_data_set_sample_spec(&source_output_data, &ss); + pa_source_output_new_data_set_channel_map(&source_output_data, &map); + source_output_data.flags = PA_SOURCE_OUTPUT_START_CORKED; + + if (!remix) + source_output_data.flags |= PA_SOURCE_OUTPUT_NO_REMIX; + + if (!format_set) + source_output_data.flags |= PA_SOURCE_OUTPUT_FIX_FORMAT; + + if (!rate_set) + source_output_data.flags |= PA_SOURCE_OUTPUT_FIX_RATE; + + if (!channels_set) + source_output_data.flags |= PA_SOURCE_OUTPUT_FIX_CHANNELS; + + source_dont_move = false; + if (pa_modargs_get_value_boolean(ma, "source_dont_move", &source_dont_move) < 0) { + pa_log("source_dont_move= expects a boolean argument."); + goto fail; + } + + if (source_dont_move) + source_output_data.flags |= PA_SOURCE_OUTPUT_DONT_MOVE; + + pa_source_output_new(&u->source_output, m->core, &source_output_data); + pa_source_output_new_data_done(&source_output_data); + + if (!u->source_output) + goto fail; + + u->source_output->parent.process_msg = source_output_process_msg_cb; + u->source_output->push = source_output_push_cb; + u->source_output->process_rewind = source_output_process_rewind_cb; + u->source_output->kill = source_output_kill_cb; + u->source_output->attach = source_output_attach_cb; + u->source_output->detach = source_output_detach_cb; + u->source_output->may_move_to = source_output_may_move_to_cb; + u->source_output->moving = source_output_moving_cb; + u->source_output->suspend = source_output_suspend_cb; + u->source_output->update_source_latency_range = update_source_latency_range_cb; + u->source_output->update_source_fixed_latency = update_source_latency_range_cb; + u->source_output->userdata = u; + + /* If format, rate or channels were originally unset, they are set now + * after the pa_source_output_new() call. */ + ss = u->source_output->sample_spec; + map = u->source_output->channel_map; + + pa_sink_input_new_data_init(&sink_input_data); + sink_input_data.driver = __FILE__; + sink_input_data.module = m; + + if (sink) + pa_sink_input_new_data_set_sink(&sink_input_data, sink, false, true); + + if (pa_modargs_get_proplist(ma, "sink_input_properties", sink_input_data.proplist, PA_UPDATE_REPLACE) < 0) { + pa_log("Failed to parse the sink_input_properties value."); + pa_sink_input_new_data_done(&sink_input_data); + goto fail; + } + + if (!pa_proplist_contains(sink_input_data.proplist, PA_PROP_MEDIA_ROLE)) + pa_proplist_sets(sink_input_data.proplist, PA_PROP_MEDIA_ROLE, "abstract"); + + pa_sink_input_new_data_set_sample_spec(&sink_input_data, &ss); + pa_sink_input_new_data_set_channel_map(&sink_input_data, &map); + sink_input_data.flags = PA_SINK_INPUT_VARIABLE_RATE | PA_SINK_INPUT_START_CORKED; + + if (!remix) + sink_input_data.flags |= PA_SINK_INPUT_NO_REMIX; + + sink_dont_move = false; + if (pa_modargs_get_value_boolean(ma, "sink_dont_move", &sink_dont_move) < 0) { + pa_log("sink_dont_move= expects a boolean argument."); + goto fail; + } + + if (sink_dont_move) + sink_input_data.flags |= PA_SINK_INPUT_DONT_MOVE; + + pa_sink_input_new(&u->sink_input, m->core, &sink_input_data); + pa_sink_input_new_data_done(&sink_input_data); + + if (!u->sink_input) + goto fail; + + u->sink_input->parent.process_msg = sink_input_process_msg_cb; + u->sink_input->pop = sink_input_pop_cb; + u->sink_input->process_rewind = sink_input_process_rewind_cb; + u->sink_input->kill = sink_input_kill_cb; + u->sink_input->state_change = sink_input_state_change_cb; + u->sink_input->attach = sink_input_attach_cb; + u->sink_input->detach = sink_input_detach_cb; + u->sink_input->update_max_rewind = sink_input_update_max_rewind_cb; + u->sink_input->update_max_request = sink_input_update_max_request_cb; + u->sink_input->may_move_to = sink_input_may_move_to_cb; + u->sink_input->moving = sink_input_moving_cb; + u->sink_input->suspend = sink_input_suspend_cb; + u->sink_input->update_sink_latency_range = update_sink_latency_range_cb; + u->sink_input->update_sink_fixed_latency = update_sink_latency_range_cb; + u->sink_input->userdata = u; + + update_latency_boundaries(u, u->source_output->source, u->sink_input->sink); + set_sink_input_latency(u, u->sink_input->sink); + set_source_output_latency(u, u->source_output->source); + + pa_sink_input_get_silence(u->sink_input, &silence); + u->memblockq = pa_memblockq_new( + "module-loopback memblockq", + 0, /* idx */ + MEMBLOCKQ_MAXLENGTH, /* maxlength */ + MEMBLOCKQ_MAXLENGTH, /* tlength */ + &ss, /* sample_spec */ + 0, /* prebuf */ + 0, /* minreq */ + 0, /* maxrewind */ + &silence); /* silence frame */ + pa_memblock_unref(silence.memblock); + /* Fill the memblockq with silence */ + pa_memblockq_seek(u->memblockq, pa_usec_to_bytes(u->latency, &u->sink_input->sample_spec), PA_SEEK_RELATIVE, true); + + u->asyncmsgq = pa_asyncmsgq_new(0); + if (!u->asyncmsgq) { + pa_log("pa_asyncmsgq_new() failed."); + goto fail; + } + + if (!pa_proplist_contains(u->source_output->proplist, PA_PROP_MEDIA_NAME)) + pa_proplist_setf(u->source_output->proplist, PA_PROP_MEDIA_NAME, "Loopback to %s", + pa_strnull(pa_proplist_gets(u->sink_input->sink->proplist, PA_PROP_DEVICE_DESCRIPTION))); + + if (!pa_proplist_contains(u->source_output->proplist, PA_PROP_MEDIA_ICON_NAME) + && (n = pa_proplist_gets(u->sink_input->sink->proplist, PA_PROP_DEVICE_ICON_NAME))) + pa_proplist_sets(u->source_output->proplist, PA_PROP_MEDIA_ICON_NAME, n); + + if (!pa_proplist_contains(u->sink_input->proplist, PA_PROP_MEDIA_NAME)) + pa_proplist_setf(u->sink_input->proplist, PA_PROP_MEDIA_NAME, "Loopback from %s", + pa_strnull(pa_proplist_gets(u->source_output->source->proplist, PA_PROP_DEVICE_DESCRIPTION))); + + if (source && !pa_proplist_contains(u->sink_input->proplist, PA_PROP_MEDIA_ICON_NAME) + && (n = pa_proplist_gets(u->source_output->source->proplist, PA_PROP_DEVICE_ICON_NAME))) + pa_proplist_sets(u->sink_input->proplist, PA_PROP_MEDIA_ICON_NAME, n); + + /* Hooks to track changes of latency offsets */ + pa_module_hook_connect(m, &m->core->hooks[PA_CORE_HOOK_SINK_PORT_LATENCY_OFFSET_CHANGED], + PA_HOOK_NORMAL, (pa_hook_cb_t) sink_port_latency_offset_changed_cb, u); + pa_module_hook_connect(m, &m->core->hooks[PA_CORE_HOOK_SOURCE_PORT_LATENCY_OFFSET_CHANGED], + PA_HOOK_NORMAL, (pa_hook_cb_t) source_port_latency_offset_changed_cb, u); + + /* Setup message handler for main thread */ + u->msg = pa_msgobject_new(loopback_msg); + u->msg->parent.process_msg = loopback_process_msg_cb; + u->msg->userdata = u; + + /* The output thread is not yet running, set effective_source_latency directly */ + update_effective_source_latency(u, u->source_output->source, NULL); + + pa_sink_input_put(u->sink_input); + pa_source_output_put(u->source_output); + + if (u->source_output->source->state != PA_SOURCE_SUSPENDED) + pa_sink_input_cork(u->sink_input, false); + + if (u->sink_input->sink->state != PA_SINK_SUSPENDED) + pa_source_output_cork(u->source_output, false); + + update_adjust_timer(u); + + pa_modargs_free(ma); + return 0; + +fail: + if (ma) + pa_modargs_free(ma); + + pa__done(m); + + return -1; +} + +void pa__done(pa_module*m) { + struct userdata *u; + + pa_assert(m); + + if (!(u = m->userdata)) + return; + + teardown(u); + + if (u->memblockq) + pa_memblockq_free(u->memblockq); + + if (u->asyncmsgq) + pa_asyncmsgq_unref(u->asyncmsgq); + + pa_xfree(u); +} |