Merge branch 'refs/heads/t/markdown'
[paraslash.git] / alsa_write.c
index 047e88f..63a7055 100644 (file)
@@ -1,5 +1,5 @@
 /*
 /*
- * Copyright (C) 2005-2011 Andre Noll <maan@systemlinux.org>
+ * Copyright (C) 2005 Andre Noll <maan@tuebingen.mpg.de>
  *
  * Licensed under the GPL v2. For licencing details see COPYING.
  */
  *
  * Licensed under the GPL v2. For licencing details see COPYING.
  */
@@ -15,8 +15,6 @@
 #include <regex.h>
 #include <sys/types.h>
 #include <alsa/asoundlib.h>
 #include <regex.h>
 #include <sys/types.h>
 #include <alsa/asoundlib.h>
-#include <sys/time.h>
-#include <stdbool.h>
 
 #include "para.h"
 #include "fd.h"
 
 #include "para.h"
 #include "fd.h"
@@ -36,21 +34,24 @@ struct private_alsa_write_data {
        snd_pcm_t *handle;
        /** Determined and set by alsa_init(). */
        int bytes_per_frame;
        snd_pcm_t *handle;
        /** Determined and set by alsa_init(). */
        int bytes_per_frame;
-       /** The approximate maximum buffer duration in us. */
-       unsigned buffer_time;
-       /* Number of frames that fit into the buffer. */
-       snd_pcm_uframes_t buffer_frames;
-       /**
-        * The sample rate given by command line option or the decoder
-        * of the writer node group.
+       /*
+        * If the sample rate is not given at the command line and no wav
+        * header was detected, the btr exec mechanism is employed to query the
+        * ancestor buffer tree nodes for this information. In a typical setup
+        * the decoder passes the sample rate back to the alsa writer.
+        *
+        *  \sa \ref btr_exec_up().
         */
        unsigned sample_rate;
         */
        unsigned sample_rate;
-       snd_pcm_format_t sample_format;
-       /**
-        * The number of channels, given by command line option or the
-        * decoder of the writer node group.
+       /*
+        * The sample format (8/16 bit, signed/unsigned, little/big endian) is
+        * determined in the same way as the \a sample_rate.
         */
         */
+       snd_pcm_format_t sample_format;
+       /* The number of channels, again determined like \a sample_rate. */
        unsigned channels;
        unsigned channels;
+       /* time until buffer underrun occurs, in milliseconds */
+       unsigned buffer_time;
        struct timeval drain_barrier;
        /* File descriptor for select(). */
        int poll_fd;
        struct timeval drain_barrier;
        /* File descriptor for select(). */
        int poll_fd;
@@ -73,80 +74,142 @@ static snd_pcm_format_t get_alsa_pcm_format(enum sample_format sf)
 static int alsa_init(struct private_alsa_write_data *pad,
                struct alsa_write_args_info *conf)
 {
 static int alsa_init(struct private_alsa_write_data *pad,
                struct alsa_write_args_info *conf)
 {
-       snd_pcm_hw_params_t *hwparams;
-       snd_pcm_sw_params_t *swparams;
+       snd_pcm_hw_params_t *hwparams = NULL;
+       snd_pcm_sw_params_t *swparams = NULL;
        snd_pcm_uframes_t start_threshold, stop_threshold;
        snd_pcm_uframes_t start_threshold, stop_threshold;
-       snd_pcm_uframes_t period_size;
-       int err;
+       snd_pcm_uframes_t buffer_size, period_size;
+       snd_output_t *output_log;
+       int ret;
+       const char *msg;
+       unsigned period_time;
 
        PARA_INFO_LOG("opening %s\n", conf->device_arg);
 
        PARA_INFO_LOG("opening %s\n", conf->device_arg);
-       err = snd_pcm_open(&pad->handle, conf->device_arg,
+       msg = "unable to open pcm";
+       ret = snd_pcm_open(&pad->handle, conf->device_arg,
                SND_PCM_STREAM_PLAYBACK, SND_PCM_NONBLOCK);
                SND_PCM_STREAM_PLAYBACK, SND_PCM_NONBLOCK);
-       if (err < 0)
-               return -E_PCM_OPEN;
-
-       snd_pcm_hw_params_alloca(&hwparams);
-       snd_pcm_sw_params_alloca(&swparams);
-       if (snd_pcm_hw_params_any(pad->handle, hwparams) < 0)
-               return -E_BROKEN_CONF;
-       if (snd_pcm_hw_params_set_access(pad->handle, hwparams,
-                       SND_PCM_ACCESS_RW_INTERLEAVED) < 0)
-               return -E_ACCESS_TYPE;
-       if (snd_pcm_hw_params_set_format(pad->handle, hwparams,
-                       pad->sample_format) < 0)
-               return -E_SAMPLE_FORMAT;
-       if (snd_pcm_hw_params_set_channels(pad->handle, hwparams,
-                       pad->channels) < 0)
-               return -E_CHANNEL_COUNT;
-       if (snd_pcm_hw_params_set_rate_near(pad->handle, hwparams,
-                       &pad->sample_rate, NULL) < 0)
-               return -E_SET_RATE;
-       err = snd_pcm_hw_params_get_buffer_time_max(hwparams,
+       if (ret < 0)
+               goto fail;
+       ret = snd_pcm_hw_params_malloc(&hwparams);
+       assert(ret >= 0);
+       msg = "Broken alsa configuration";
+       ret = snd_pcm_hw_params_any(pad->handle, hwparams);
+       if (ret < 0)
+               goto fail;
+       msg = "access type not available";
+       ret = snd_pcm_hw_params_set_access(pad->handle, hwparams,
+               SND_PCM_ACCESS_RW_INTERLEAVED);
+       if (ret < 0)
+               goto fail;
+       msg = "sample format not available";
+       ret = snd_pcm_hw_params_set_format(pad->handle, hwparams,
+               pad->sample_format);
+       if (ret < 0)
+               goto fail;
+       msg = "channels count not available";
+       ret = snd_pcm_hw_params_set_channels(pad->handle, hwparams,
+               pad->channels);
+       if (ret < 0)
+               goto fail;
+       msg = "could not set sample rate";
+       ret = snd_pcm_hw_params_set_rate_near(pad->handle, hwparams,
+               &pad->sample_rate, NULL);
+       if (ret < 0)
+               goto fail;
+       /* alsa wants microseconds */
+       pad->buffer_time = conf->buffer_time_arg * 1000;
+       msg = "could not set buffer time";
+       ret = snd_pcm_hw_params_set_buffer_time_near(pad->handle, hwparams,
                &pad->buffer_time, NULL);
                &pad->buffer_time, NULL);
-       if (err < 0 || !pad->buffer_time)
-               return -E_GET_BUFFER_TIME;
-       PARA_INFO_LOG("buffer time: %d\n", pad->buffer_time);
-       if (snd_pcm_hw_params_set_buffer_time_near(pad->handle, hwparams,
-                       &pad->buffer_time, NULL) < 0)
-               return -E_SET_BUFFER_TIME;
-       if (snd_pcm_hw_params(pad->handle, hwparams) < 0)
-               return -E_HW_PARAMS;
+       if (ret < 0)
+               goto fail;
+       pad->buffer_time /= 1000; /* we prefer milliseconds */
+       period_time = pad->buffer_time * 250; /* buffer time / 4 */
+       msg = "could not set period time";
+       ret = snd_pcm_hw_params_set_period_time_near(pad->handle, hwparams,
+               &period_time, NULL);
+       if (ret < 0)
+               goto fail;
+
+       msg = "unable to install hw params";
+       ret = snd_pcm_hw_params(pad->handle, hwparams);
+       if (ret < 0)
+               goto fail;
        snd_pcm_hw_params_get_period_size(hwparams, &period_size, NULL);
        snd_pcm_hw_params_get_period_size(hwparams, &period_size, NULL);
-       snd_pcm_hw_params_get_buffer_size(hwparams, &pad->buffer_frames);
-       PARA_INFO_LOG("buffer size: %lu, period_size: %lu\n", pad->buffer_frames,
-               period_size);
-       if (period_size == pad->buffer_frames)
-               return -E_BAD_PERIOD;
+       snd_pcm_hw_params_get_buffer_size(hwparams, &buffer_size);
+       msg = "period size equals buffer size";
+       if (period_size == buffer_size)
+               goto fail;
+
+       /* software parameter setup */
+       ret = snd_pcm_sw_params_malloc(&swparams);
+       assert(ret >= 0);
        snd_pcm_sw_params_current(pad->handle, swparams);
        snd_pcm_sw_params_set_avail_min(pad->handle, swparams, period_size);
        snd_pcm_sw_params_current(pad->handle, swparams);
        snd_pcm_sw_params_set_avail_min(pad->handle, swparams, period_size);
-       if (pad->buffer_frames < 1)
+       if (buffer_size < 1)
                start_threshold = 1;
        else
                start_threshold = 1;
        else
-               start_threshold = PARA_MIN(pad->buffer_frames,
+               start_threshold = PARA_MIN(buffer_size,
                        (snd_pcm_uframes_t)pad->sample_rate);
                        (snd_pcm_uframes_t)pad->sample_rate);
-       if (snd_pcm_sw_params_set_start_threshold(pad->handle, swparams,
-                       start_threshold) < 0)
-               return -E_START_THRESHOLD;
-       stop_threshold = pad->buffer_frames;
-       if (snd_pcm_sw_params_set_stop_threshold(pad->handle, swparams,
-                       stop_threshold) < 0)
-               return -E_STOP_THRESHOLD;
-       if (snd_pcm_sw_params(pad->handle, swparams) < 0)
-               PARA_WARNING_LOG("unable to install sw params\n");
-       pad->bytes_per_frame = snd_pcm_format_physical_width(pad->sample_format)
-               * pad->channels / 8;
-       if (pad->bytes_per_frame <= 0)
-               return -E_PHYSICAL_WIDTH;
-       PARA_INFO_LOG("bytes per frame: %d\n", pad->bytes_per_frame);
-       if (snd_pcm_nonblock(pad->handle, 1))
-               PARA_ERROR_LOG("failed to set nonblock mode\n");
-       return 1;
+       msg = "could not set start threshold";
+       ret = snd_pcm_sw_params_set_start_threshold(pad->handle, swparams,
+               start_threshold);
+       if (ret < 0)
+               goto fail;
+       stop_threshold = buffer_size;
+       msg = "could not set stop threshold";
+       ret = snd_pcm_sw_params_set_stop_threshold(pad->handle, swparams,
+               stop_threshold);
+       if (ret < 0)
+               goto fail;
+       msg = "unable to install sw params";
+       ret = snd_pcm_sw_params(pad->handle, swparams);
+       if (ret < 0)
+               goto fail;
+       msg = "unable to determine bytes per frame";
+       ret = snd_pcm_format_physical_width(pad->sample_format);
+       if (ret <= 0)
+               goto fail;
+       pad->bytes_per_frame = ret * pad->channels / 8;
+       msg = "failed to set alsa handle to nonblock mode";
+       ret = snd_pcm_nonblock(pad->handle, 1);
+       if (ret < 0)
+               goto fail;
+       ret = snd_output_buffer_open(&output_log);
+       if (ret == 0) {
+               char *buf, *p;
+               size_t sz;
+               PARA_DEBUG_LOG("dumping alsa configuration\n");
+               snd_pcm_dump(pad->handle, output_log);
+               snd_pcm_hw_params_dump(hwparams, output_log);
+               sz = snd_output_buffer_string(output_log, &buf);
+               for (p = buf; p < buf + sz;) {
+                       char *q = memchr(p, '\n', buf + sz - p);
+                       if (!q)
+                               break;
+                       *q = '\0';
+                       PARA_DEBUG_LOG("%s\n", p);
+                       p = q + 1;
+               }
+               snd_output_close(output_log);
+       }
+       ret = 1;
+       goto out;
+fail:
+       if (ret < 0)
+               PARA_ERROR_LOG("%s: %s\n", msg, snd_strerror(-ret));
+       else
+               PARA_ERROR_LOG("%s\n", msg);
+       ret = -E_ALSA;
+out:
+       snd_pcm_hw_params_free(hwparams);
+       snd_pcm_sw_params_free(swparams);
+       return ret;
 }
 
 }
 
-static void alsa_write_pre_select(struct sched *s, struct task *t)
+static void alsa_write_pre_select(struct sched *s, void *context)
 {
        struct pollfd pfd;
 {
        struct pollfd pfd;
-       struct writer_node *wn = container_of(t, struct writer_node, task);
+       struct writer_node *wn = context;
        struct private_alsa_write_data *pad = wn->private_data;
        int ret = btr_node_status(wn->btrn, wn->min_iqs, BTR_NT_LEAF);
 
        struct private_alsa_write_data *pad = wn->private_data;
        int ret = btr_node_status(wn->btrn, wn->min_iqs, BTR_NT_LEAF);
 
@@ -162,10 +225,12 @@ static void alsa_write_pre_select(struct sched *s, struct task *t)
                sched_request_barrier_or_min_delay(&pad->drain_barrier, s);
                return;
        }
                sched_request_barrier_or_min_delay(&pad->drain_barrier, s);
                return;
        }
+       /* wait at most 50% of the buffer time */
+       sched_request_timeout_ms(pad->buffer_time / 2, s);
        ret = snd_pcm_poll_descriptors(pad->handle, &pfd, 1);
        if (ret < 0) {
        ret = snd_pcm_poll_descriptors(pad->handle, &pfd, 1);
        if (ret < 0) {
-               PARA_ERROR_LOG("%s\n", snd_strerror(-ret));
-               t->error = -E_ALSA_POLL_FDS;
+               PARA_ERROR_LOG("could not get alsa poll fd: %s\n",
+                       snd_strerror(-ret));
                return;
        }
        pad->poll_fd = pfd.fd;
                return;
        }
        pad->poll_fd = pfd.fd;
@@ -190,10 +255,9 @@ static void alsa_close(struct writer_node *wn)
        free(pad);
 }
 
        free(pad);
 }
 
-static void alsa_write_post_select(__a_unused struct sched *s,
-               struct task *t)
+static int alsa_write_post_select(__a_unused struct sched *s, void *context)
 {
 {
-       struct writer_node *wn = container_of(t, struct writer_node, task);
+       struct writer_node *wn = context;
        struct private_alsa_write_data *pad = wn->private_data;
        struct btr_node *btrn = wn->btrn;
        char *data;
        struct private_alsa_write_data *pad = wn->private_data;
        struct btr_node *btrn = wn->btrn;
        char *data;
@@ -201,11 +265,13 @@ static void alsa_write_post_select(__a_unused struct sched *s,
        snd_pcm_sframes_t frames;
        int ret;
 
        snd_pcm_sframes_t frames;
        int ret;
 
+       ret = task_get_notification(wn->task);
+       if (ret < 0)
+               goto err;
 again:
 again:
-       t->error = 0;
        ret = btr_node_status(btrn, wn->min_iqs, BTR_NT_LEAF);
        if (ret == 0)
        ret = btr_node_status(btrn, wn->min_iqs, BTR_NT_LEAF);
        if (ret == 0)
-               return;
+               return 0;
        btr_merge(btrn, wn->min_iqs);
        bytes = btr_next_buffer(btrn, &data);
        if (ret < 0 || bytes < wn->min_iqs) { /* eof */
        btr_merge(btrn, wn->min_iqs);
        bytes = btr_next_buffer(btrn, &data);
        if (ret < 0 || bytes < wn->min_iqs) { /* eof */
@@ -218,17 +284,17 @@ again:
                        PARA_DEBUG_LOG("waiting for device to drain\n");
                        tv_add(now, &(struct timeval)EMBRACE(0, 200 * 1000),
                                &pad->drain_barrier);
                        PARA_DEBUG_LOG("waiting for device to drain\n");
                        tv_add(now, &(struct timeval)EMBRACE(0, 200 * 1000),
                                &pad->drain_barrier);
-                       return;
+                       return 0;
                }
                if (tv_diff(now, &pad->drain_barrier, NULL) > 0)
                        goto err;
                }
                if (tv_diff(now, &pad->drain_barrier, NULL) > 0)
                        goto err;
-               return;
+               return 0;
        }
        if (!pad) {
                int32_t val;
 
                if (bytes == 0) /* no data available */
        }
        if (!pad) {
                int32_t val;
 
                if (bytes == 0) /* no data available */
-                       return;
+                       return 0;
                pad = para_calloc(sizeof(*pad));
                get_btr_sample_rate(btrn, &val);
                pad->sample_rate = val;
                pad = para_calloc(sizeof(*pad));
                get_btr_sample_rate(btrn, &val);
                pad->sample_rate = val;
@@ -248,12 +314,15 @@ again:
                wn->min_iqs = pad->bytes_per_frame;
                goto again;
        }
                wn->min_iqs = pad->bytes_per_frame;
                goto again;
        }
-       if (pad->poll_fd >= 0 && !FD_ISSET(pad->poll_fd, &s->rfds))
-               return;
        frames = bytes / pad->bytes_per_frame;
        frames = snd_pcm_writei(pad->handle, data, frames);
        frames = bytes / pad->bytes_per_frame;
        frames = snd_pcm_writei(pad->handle, data, frames);
-       if (frames == 0 || frames == -EAGAIN)
-               return;
+       if (frames == 0 || frames == -EAGAIN) {
+               char buf[100];
+               if (pad->poll_fd >= 0 && FD_ISSET(pad->poll_fd, &s->rfds))
+                       if (read(pad->poll_fd, buf, 100))
+                               do_nothing;
+               return 0;
+       }
        if (frames > 0) {
                btr_consume(btrn, frames * pad->bytes_per_frame);
                goto again;
        if (frames > 0) {
                btr_consume(btrn, frames * pad->bytes_per_frame);
                goto again;
@@ -261,28 +330,28 @@ again:
        if (frames == -EPIPE) {
                PARA_WARNING_LOG("underrun (tried to write %zu bytes)\n", bytes);
                snd_pcm_prepare(pad->handle);
        if (frames == -EPIPE) {
                PARA_WARNING_LOG("underrun (tried to write %zu bytes)\n", bytes);
                snd_pcm_prepare(pad->handle);
-               return;
+               return 0;
        }
        }
-       PARA_WARNING_LOG("%s\n", snd_strerror(-frames));
-       ret = -E_ALSA_WRITE;
+       PARA_ERROR_LOG("alsa write error: %s\n", snd_strerror(-frames));
+       ret = -E_ALSA;
 err:
        assert(ret < 0);
 err:
        assert(ret < 0);
-       btr_remove_node(btrn);
-       t->error = ret;
+       btr_remove_node(&wn->btrn);
+       return ret;
 }
 
 }
 
-__malloc static void *alsa_parse_config_or_die(const char *options)
+__malloc static void *alsa_parse_config_or_die(int argc, char **argv)
 {
        struct alsa_write_args_info *conf = para_calloc(sizeof(*conf));
 
        /* exits on errors */
 {
        struct alsa_write_args_info *conf = para_calloc(sizeof(*conf));
 
        /* exits on errors */
-       alsa_cmdline_parser_string(options, conf, "alsa_write");
+       alsa_write_cmdline_parser(argc, argv, conf);
        return conf;
 }
 
 static void alsa_free_config(void *conf)
 {
        return conf;
 }
 
 static void alsa_free_config(void *conf)
 {
-       alsa_cmdline_parser_free(conf);
+       alsa_write_cmdline_parser_free(conf);
 }
 
 /**
 }
 
 /**
@@ -296,16 +365,12 @@ void alsa_write_init(struct writer *w)
 {
        struct alsa_write_args_info dummy;
 
 {
        struct alsa_write_args_info dummy;
 
-       alsa_cmdline_parser_init(&dummy);
+       alsa_write_cmdline_parser_init(&dummy);
        w->close = alsa_close;
        w->pre_select = alsa_write_pre_select;
        w->post_select = alsa_write_post_select;
        w->parse_config_or_die = alsa_parse_config_or_die;
        w->close = alsa_close;
        w->pre_select = alsa_write_pre_select;
        w->post_select = alsa_write_post_select;
        w->parse_config_or_die = alsa_parse_config_or_die;
-       w->shutdown = NULL; /* nothing to do */
        w->free_config = alsa_free_config;
        w->free_config = alsa_free_config;
-       w->help = (struct ggo_help) {
-               .short_help = alsa_write_args_info_help,
-               .detailed_help = alsa_write_args_info_detailed_help
-       };
-       alsa_cmdline_parser_free(&dummy);
+       w->help = (struct ggo_help)DEFINE_GGO_HELP(alsa_write);
+       alsa_write_cmdline_parser_free(&dummy);
 }
 }