1 files changed, 333 insertions, 0 deletions

diff --git a/src/modules/module-sine-source.c b/src/modules/module-sine-source.c
new file mode 100644
index 0000000..803fae5
--- /dev/null
+++ b/src/modules/module-sine-source.c
@@ -0,0 +1,333 @@
+/***
+  This file is part of PulseAudio.
+
+  Copyright 2008 Lennart Poettering
+
+  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 <stdlib.h>
+#include <stdio.h>
+#include <errno.h>
+#include <unistd.h>
+
+#include <pulse/rtclock.h>
+#include <pulse/timeval.h>
+#include <pulse/xmalloc.h>
+
+#include <pulsecore/source.h>
+#include <pulsecore/module.h>
+#include <pulsecore/core-util.h>
+#include <pulsecore/modargs.h>
+#include <pulsecore/log.h>
+#include <pulsecore/thread.h>
+#include <pulsecore/thread-mq.h>
+#include <pulsecore/rtpoll.h>
+
+PA_MODULE_AUTHOR("Lennart Poettering");
+PA_MODULE_DESCRIPTION("Sine wave generator source");
+PA_MODULE_VERSION(PACKAGE_VERSION);
+PA_MODULE_LOAD_ONCE(false);
+PA_MODULE_USAGE(
+        "source_name=<name for the source> "
+        "source_properties=<properties for the source> "
+        "rate=<sample rate> "
+        "frequency=<frequency in Hz>");
+
+#define DEFAULT_SOURCE_NAME "sine_input"
+#define BLOCK_USEC (PA_USEC_PER_SEC * 2)
+
+struct userdata {
+    pa_core *core;
+    pa_module *module;
+    pa_source *source;
+
+    pa_thread *thread;
+    pa_thread_mq thread_mq;
+    pa_rtpoll *rtpoll;
+
+    pa_memchunk memchunk;
+    size_t peek_index;
+
+    pa_usec_t block_usec; /* how much to push at once */
+    pa_usec_t timestamp;  /* when to push next */
+};
+
+static const char* const valid_modargs[] = {
+    "source_name",
+    "source_properties",
+    "rate",
+    "frequency",
+    NULL
+};
+
+static int source_process_msg(
+        pa_msgobject *o,
+        int code,
+        void *data,
+        int64_t offset,
+        pa_memchunk *chunk) {
+
+    struct userdata *u = PA_SOURCE(o)->userdata;
+
+    switch (code) {
+
+        case PA_SOURCE_MESSAGE_GET_LATENCY: {
+            pa_usec_t now, left_to_fill;
+
+            now = pa_rtclock_now();
+            left_to_fill = u->timestamp > now ? u->timestamp - now : 0ULL;
+
+            *((int64_t*) data) = (int64_t)u->block_usec - left_to_fill;
+
+            return 0;
+        }
+    }
+
+    return pa_source_process_msg(o, code, data, offset, chunk);
+}
+
+/* Called from the IO thread. */
+static int source_set_state_in_io_thread_cb(pa_source *s, pa_source_state_t new_state, pa_suspend_cause_t new_suspend_cause) {
+    struct userdata *u;
+
+    pa_assert(s);
+    pa_assert_se(u = s->userdata);
+
+    if (new_state == PA_SOURCE_RUNNING)
+        u->timestamp = pa_rtclock_now();
+
+    return 0;
+}
+
+static void source_update_requested_latency_cb(pa_source *s) {
+    struct userdata *u;
+
+    pa_source_assert_ref(s);
+    pa_assert_se(u = s->userdata);
+
+    u->block_usec = pa_source_get_requested_latency_within_thread(s);
+
+    if (u->block_usec == (pa_usec_t) -1)
+        u->block_usec = s->thread_info.max_latency;
+
+    pa_log_debug("new block msec = %lu", (unsigned long) (u->block_usec / PA_USEC_PER_MSEC));
+}
+
+static void process_render(struct userdata *u, pa_usec_t now) {
+    pa_assert(u);
+
+    while (u->timestamp < now + u->block_usec) {
+        pa_memchunk chunk;
+        size_t k;
+
+        k = pa_usec_to_bytes_round_up(now + u->block_usec - u->timestamp, &u->source->sample_spec);
+
+        chunk = u->memchunk;
+        chunk.index += u->peek_index;
+        chunk.length = PA_MIN(chunk.length - u->peek_index, k);
+
+/*         pa_log_debug("posting %lu", (unsigned long) chunk.length); */
+        pa_source_post(u->source, &chunk);
+
+        u->peek_index += chunk.length;
+        while (u->peek_index >= u->memchunk.length)
+            u->peek_index -= u->memchunk.length;
+
+        u->timestamp += pa_bytes_to_usec(chunk.length, &u->source->sample_spec);
+    }
+}
+
+static void thread_func(void *userdata) {
+    struct userdata *u = userdata;
+
+    pa_assert(u);
+
+    pa_log_debug("Thread starting up");
+
+    pa_thread_mq_install(&u->thread_mq);
+
+    u->timestamp = pa_rtclock_now();
+
+    for (;;) {
+        int ret;
+
+        if (PA_SOURCE_IS_OPENED(u->source->thread_info.state)) {
+            pa_usec_t now;
+
+            now = pa_rtclock_now();
+
+            if (u->timestamp <= now)
+                process_render(u, now);
+
+            pa_rtpoll_set_timer_absolute(u->rtpoll, u->timestamp);
+        } else
+            pa_rtpoll_set_timer_disabled(u->rtpoll);
+
+        /* Hmm, nothing to do. Let's sleep */
+        if ((ret = pa_rtpoll_run(u->rtpoll)) < 0)
+            goto fail;
+
+        if (ret == 0)
+            goto finish;
+    }
+
+fail:
+    /* If this was no regular exit from the loop we have to continue
+     * processing messages until we received PA_MESSAGE_SHUTDOWN */
+    pa_asyncmsgq_post(u->thread_mq.outq, PA_MSGOBJECT(u->core), PA_CORE_MESSAGE_UNLOAD_MODULE, u->module, 0, NULL, NULL);
+    pa_asyncmsgq_wait_for(u->thread_mq.inq, PA_MESSAGE_SHUTDOWN);
+
+finish:
+    pa_log_debug("Thread shutting down");
+}
+
+int pa__init(pa_module*m) {
+    struct userdata *u;
+    pa_modargs *ma;
+    pa_source_new_data data;
+    uint32_t frequency;
+    pa_sample_spec ss;
+
+    pa_assert(m);
+
+    if (!(ma = pa_modargs_new(m->argument, valid_modargs))) {
+        pa_log("failed to parse module arguments.");
+        goto fail;
+    }
+
+    ss.format = PA_SAMPLE_FLOAT32;
+    ss.channels = 1;
+    ss.rate = 44100;
+
+    if (pa_modargs_get_sample_rate(ma, &ss.rate) < 0) {
+        pa_log("Invalid rate specification");
+        goto fail;
+    }
+
+    frequency = 440;
+    if (pa_modargs_get_value_u32(ma, "frequency", &frequency) < 0 || frequency < 1 || frequency > ss.rate/2) {
+        pa_log("Invalid frequency specification");
+        goto fail;
+    }
+
+    m->userdata = u = pa_xnew0(struct userdata, 1);
+    u->core = m->core;
+    u->module = m;
+    u->rtpoll = pa_rtpoll_new();
+
+    if (pa_thread_mq_init(&u->thread_mq, m->core->mainloop, u->rtpoll) < 0) {
+        pa_log("pa_thread_mq_init() failed.");
+        goto fail;
+    }
+
+    u->peek_index = 0;
+    pa_memchunk_sine(&u->memchunk, m->core->mempool, ss.rate, frequency);
+
+    pa_source_new_data_init(&data);
+    data.driver = __FILE__;
+    data.module = m;
+    pa_source_new_data_set_name(&data, pa_modargs_get_value(ma, "source_name", DEFAULT_SOURCE_NAME));
+    pa_proplist_setf(data.proplist, PA_PROP_DEVICE_DESCRIPTION, "Sine source at %u Hz", (unsigned) frequency);
+    pa_proplist_sets(data.proplist, PA_PROP_DEVICE_CLASS, "abstract");
+    pa_proplist_setf(data.proplist, "sine.hz", "%u", frequency);
+    pa_source_new_data_set_sample_spec(&data, &ss);
+
+    if (pa_modargs_get_proplist(ma, "source_properties", data.proplist, PA_UPDATE_REPLACE) < 0) {
+        pa_log("Invalid properties");
+        pa_source_new_data_done(&data);
+        goto fail;
+    }
+
+    u->source = pa_source_new(m->core, &data, PA_SOURCE_LATENCY);
+    pa_source_new_data_done(&data);
+
+    if (!u->source) {
+        pa_log("Failed to create source.");
+        goto fail;
+    }
+
+    u->source->parent.process_msg = source_process_msg;
+    u->source->set_state_in_io_thread = source_set_state_in_io_thread_cb;
+    u->source->update_requested_latency = source_update_requested_latency_cb;
+    u->source->userdata = u;
+
+    u->block_usec = BLOCK_USEC;
+
+    pa_source_set_asyncmsgq(u->source, u->thread_mq.inq);
+    pa_source_set_rtpoll(u->source, u->rtpoll);
+    pa_source_set_fixed_latency(u->source, u->block_usec);
+
+    if (!(u->thread = pa_thread_new("sine-source", thread_func, u))) {
+        pa_log("Failed to create thread.");
+        goto fail;
+    }
+
+    pa_source_put(u->source);
+
+    pa_modargs_free(ma);
+
+    return 0;
+
+fail:
+    if (ma)
+        pa_modargs_free(ma);
+
+    pa__done(m);
+
+    return -1;
+}
+
+int pa__get_n_used(pa_module *m) {
+    struct userdata *u;
+
+    pa_assert(m);
+    pa_assert_se(u = m->userdata);
+
+    return pa_source_linked_by(u->source);
+}
+
+void pa__done(pa_module*m) {
+    struct userdata *u;
+
+    pa_assert(m);
+
+    if (!(u = m->userdata))
+        return;
+
+    if (u->source)
+        pa_source_unlink(u->source);
+
+    if (u->thread) {
+        pa_asyncmsgq_send(u->thread_mq.inq, NULL, PA_MESSAGE_SHUTDOWN, NULL, 0, NULL);
+        pa_thread_free(u->thread);
+    }
+
+    pa_thread_mq_done(&u->thread_mq);
+
+    if (u->source)
+        pa_source_unref(u->source);
+
+    if (u->memchunk.memblock)
+        pa_memblock_unref(u->memchunk.memblock);
+
+    if (u->rtpoll)
+        pa_rtpoll_free(u->rtpoll);
+
+    pa_xfree(u);
+}