aft: Change return type of make_status_items() to void.
[paraslash.git] / alsa_write.c
index ad59a82..363e393 100644 (file)
@@ -1,8 +1,4 @@
-/*
- * Copyright (C) 2005-2014 Andre Noll <maan@systemlinux.org>
- *
- * Licensed under the GPL v2. For licencing details see COPYING.
- */
+/* Copyright (C) 2005 Andre Noll <maan@tuebingen.mpg.de>, see file COPYING. */
 
 /** \file alsa_write.c paraslash's alsa output plugin */
 
 #include <regex.h>
 #include <sys/types.h>
 #include <alsa/asoundlib.h>
+#include <lopsub.h>
 
+#include "write_cmd.lsg.h"
 #include "para.h"
 #include "fd.h"
 #include "string.h"
 #include "list.h"
 #include "sched.h"
-#include "ggo.h"
 #include "buffer_tree.h"
 #include "write.h"
-#include "write_common.h"
-#include "alsa_write.cmdline.h"
 #include "error.h"
 
 /** Data specific to the alsa writer. */
@@ -34,17 +29,24 @@ struct private_alsa_write_data {
        snd_pcm_t *handle;
        /** Determined and set by alsa_init(). */
        int bytes_per_frame;
-       /**
-        * 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;
-       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;
+       /* time until buffer underrun occurs, in milliseconds */
+       unsigned buffer_time;
        struct timeval drain_barrier;
        /* File descriptor for select(). */
        int poll_fd;
@@ -64,25 +66,26 @@ static snd_pcm_format_t get_alsa_pcm_format(enum sample_format sf)
 }
 
 /* Install PCM software and hardware configuration. */
-static int alsa_init(struct private_alsa_write_data *pad,
-               struct alsa_write_args_info *conf)
+static int alsa_init(struct writer_node *wn)
 {
-       snd_pcm_hw_params_t *hwparams;
-       snd_pcm_sw_params_t *swparams;
+       struct private_alsa_write_data *pad = wn->private_data;
+       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 buffer_size, period_size;
        snd_output_t *output_log;
-       unsigned buffer_time;
        int ret;
-       const char *msg;
+       const char *msg, *dev = WRITE_CMD_OPT_STRING_VAL(ALSA, DEVICE, wn->lpr);
+       unsigned period_time;
 
-       PARA_INFO_LOG("opening %s\n", conf->device_arg);
+       PARA_INFO_LOG("opening %s\n", dev);
        msg = "unable to open pcm";
-       ret = snd_pcm_open(&pad->handle, conf->device_arg,
-               SND_PCM_STREAM_PLAYBACK, SND_PCM_NONBLOCK);
+       ret = snd_pcm_open(&pad->handle, dev, SND_PCM_STREAM_PLAYBACK,
+               SND_PCM_NONBLOCK);
        if (ret < 0)
                goto fail;
-       snd_pcm_hw_params_alloca(&hwparams);
+       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)
@@ -107,18 +110,22 @@ static int alsa_init(struct private_alsa_write_data *pad,
                &pad->sample_rate, NULL);
        if (ret < 0)
                goto fail;
-       msg = "unable to get buffer time";
-       ret = snd_pcm_hw_params_get_buffer_time_max(hwparams, &buffer_time,
-               NULL);
-       if (ret < 0 || buffer_time == 0)
-               goto fail;
-       /* buffer at most 500 milliseconds */
-       buffer_time = PARA_MIN(buffer_time, 500U * 1000U);
+       /* alsa wants microseconds */
+       pad->buffer_time = 1000U * WRITE_CMD_OPT_UINT32_VAL(ALSA, BUFFER_TIME,
+               wn->lpr);
        msg = "could not set buffer time";
        ret = snd_pcm_hw_params_set_buffer_time_near(pad->handle, hwparams,
-               &buffer_time, NULL);
+               &pad->buffer_time, NULL);
        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)
@@ -130,7 +137,8 @@ static int alsa_init(struct private_alsa_write_data *pad,
                goto fail;
 
        /* software parameter setup */
-       snd_pcm_sw_params_alloca(&swparams);
+       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);
        if (buffer_size < 1)
@@ -166,32 +174,38 @@ static int alsa_init(struct private_alsa_write_data *pad,
        if (ret == 0) {
                char *buf, *p;
                size_t sz;
-               PARA_INFO_LOG("dumping alsa configuration\n");
+               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_INFO_LOG("%s\n", p);
+                       PARA_DEBUG_LOG("%s\n", p);
                        p = q + 1;
                }
                snd_output_close(output_log);
        }
-       return 1;
+       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);
-       return -E_ALSA;
+       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 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);
 
@@ -207,11 +221,12 @@ static void alsa_write_pre_select(struct sched *s, struct task *t)
                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) {
                PARA_ERROR_LOG("could not get alsa poll fd: %s\n",
                        snd_strerror(-ret));
-               t->error = -E_ALSA;
                return;
        }
        pad->poll_fd = pfd.fd;
@@ -236,10 +251,9 @@ static void alsa_close(struct writer_node *wn)
        free(pad);
 }
 
-static int 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;
@@ -247,7 +261,7 @@ static int alsa_write_post_select(__a_unused struct sched *s,
        snd_pcm_sframes_t frames;
        int ret;
 
-       ret = task_get_notification(t);
+       ret = task_get_notification(wn->task);
        if (ret < 0)
                goto err;
 again:
@@ -277,7 +291,7 @@ again:
 
                if (bytes == 0) /* no data available */
                        return 0;
-               pad = para_calloc(sizeof(*pad));
+               pad = wn->private_data = para_calloc(sizeof(*pad));
                get_btr_sample_rate(btrn, &val);
                pad->sample_rate = val;
                get_btr_channels(btrn, &val);
@@ -285,32 +299,24 @@ again:
                get_btr_sample_format(btrn, &val);
                pad->sample_format = get_alsa_pcm_format(val);
 
-               PARA_INFO_LOG("%d channel(s), %dHz\n", pad->channels,
+               PARA_INFO_LOG("%u channel(s), %uHz\n", pad->channels,
                        pad->sample_rate);
-               ret = alsa_init(pad, wn->conf);
+               ret = alsa_init(wn);
                if (ret < 0) {
-                       free(pad);
+                       free(wn->private_data);
+                       wn->private_data = NULL;
                        goto err;
                }
-               wn->private_data = pad;
                wn->min_iqs = pad->bytes_per_frame;
                goto again;
        }
-       if (pad->poll_fd < 0 || !FD_ISSET(pad->poll_fd, &s->rfds))
-               return 0;
        frames = bytes / pad->bytes_per_frame;
        frames = snd_pcm_writei(pad->handle, data, frames);
        if (frames == 0 || frames == -EAGAIN) {
-               /*
-                * The alsa poll fd was ready for IO but we failed to write to
-                * the alsa handle. This means another event is pending. We
-                * don't care about that but we have to dispatch the event in
-                * order to avoid a busy loop. So we simply read from the poll
-                * fd.
-                */
                char buf[100];
-               if (read(pad->poll_fd, buf, 100))
-                       do_nothing;
+               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) {
@@ -330,37 +336,9 @@ err:
        return ret;
 }
 
-__malloc static void *alsa_parse_config_or_die(int argc, char **argv)
-{
-       struct alsa_write_args_info *conf = para_calloc(sizeof(*conf));
+struct writer lsg_write_cmd_com_alsa_user_data = {
 
-       /* exits on errors */
-       alsa_write_cmdline_parser(argc, argv, conf);
-       return conf;
-}
-
-static void alsa_free_config(void *conf)
-{
-       alsa_write_cmdline_parser_free(conf);
-}
-
-/**
- * The init function of the alsa writer.
- *
- * \param w Pointer to the writer to initialize.
- *
- * \sa struct \ref writer.
- */
-void alsa_write_init(struct writer *w)
-{
-       struct alsa_write_args_info 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->free_config = alsa_free_config;
-       w->help = (struct ggo_help)DEFINE_GGO_HELP(alsa_write);
-       alsa_write_cmdline_parser_free(&dummy);
-}
+       .pre_select = alsa_write_pre_select,
+       .post_select = alsa_write_post_select,
+       .close = alsa_close,
+};