server: Fix brown paper bag bug in generic_com_on().
[paraslash.git] / oss_write.c
index 8ca3c52..d4b7658 100644 (file)
@@ -1,26 +1,20 @@
-/*
- * Copyright (C) 2009-2012 Andre Noll <maan@systemlinux.org>
- *
- * Licensed under the GPL v2. For licencing details see COPYING.
- */
+/* Copyright (C) 2009 Andre Noll <maan@tuebingen.mpg.de>, see file COPYING. */
 
 /** \file oss_write.c Paraslash's oss output plugin. */
 
 #include <regex.h>
 #include <sys/ioctl.h>
-#include <fcntl.h>
 #include <sys/soundcard.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 "oss_write.cmdline.h"
 #include "error.h"
 
 /** Data specific to the oss writer. */
@@ -31,6 +25,29 @@ struct private_oss_write_data {
        int bytes_per_frame;
 };
 
+/*
+ * We keep one bit of static storage to make sure only one instance of the oss
+ * writer is running at any given time.
+ */
+static bool sound_device_busy;
+
+static bool sound_device_is_busy(void)
+{
+       return sound_device_busy;
+}
+
+static void set_sound_device_busy(void)
+{
+       assert(!sound_device_busy);
+       sound_device_busy = true;
+}
+
+static void set_sound_device_idle(void)
+{
+       assert(sound_device_busy);
+       sound_device_busy = false;
+}
+
 static int get_oss_format(enum sample_format sf)
 {
        switch (sf) {
@@ -44,13 +61,13 @@ static int get_oss_format(enum sample_format sf)
        }
 }
 
-static void oss_pre_select(struct sched *s, struct task *t)
+static void oss_pre_select(struct sched *s, void *context)
 {
-       struct writer_node *wn = container_of(t, struct writer_node, task);
+       struct writer_node *wn = context;
        struct private_oss_write_data *powd = wn->private_data;
        int ret = btr_node_status(wn->btrn, wn->min_iqs, BTR_NT_LEAF);
 
-       if (ret == 0)
+       if (ret == 0 || (sound_device_is_busy() && !powd))
                return;
        if (ret < 0 || !powd)
                return sched_min_delay(s);
@@ -65,6 +82,7 @@ static void oss_close(struct writer_node *wn)
                return;
        close(powd->fd);
        free(powd);
+       set_sound_device_idle();
 }
 
 /*
@@ -83,11 +101,11 @@ static int oss_init(struct writer_node *wn, unsigned sample_rate,
 {
        int ret, format;
        unsigned ch, rate;
-       struct oss_write_args_info *conf = wn->conf;
        struct private_oss_write_data *powd = para_calloc(sizeof(*powd));
+       const char *dev = WRITE_CMD_OPT_STRING_VAL(OSS, DEVICE, wn->lpr);
 
-       PARA_INFO_LOG("opening %s\n", conf->device_arg);
-       ret = para_open(conf->device_arg, O_WRONLY, 0);
+       PARA_INFO_LOG("opening %s\n", dev);
+       ret = para_open(dev, O_WRONLY, 0);
        if (ret < 0)
                goto err_free;
        powd->fd = ret;
@@ -123,7 +141,7 @@ static int oss_init(struct writer_node *wn, unsigned sample_rate,
         * Set sampling rate
         *
         * If we request a higher sampling rate than is supported by the
-        * device, the the highest possible speed is automatically used. The
+        * device, the highest possible speed is automatically used. The
         * value actually used is returned as the new value of the argument.
         */
        rate = sample_rate;
@@ -142,7 +160,7 @@ static int oss_init(struct writer_node *wn, unsigned sample_rate,
                ret = -E_BAD_SAMPLERATE;
                if (100 * max > 110 * min) /* more than 10% deviation */
                        goto err;
-               PARA_NOTICE_LOG("using %dHz rather than %dHz\n", rate,
+               PARA_NOTICE_LOG("using %uHz rather than %uHz\n", rate,
                        sample_rate);
        }
        wn->min_iqs = powd->bytes_per_frame;
@@ -152,22 +170,21 @@ err:
        close(powd->fd);
 err_free:
        free(powd);
-       PARA_ERROR_LOG("failed to init %s: %s\n", conf->device_arg,
-               para_strerror(-ret));
+       PARA_ERROR_LOG("failed to init %s: %s\n", dev, para_strerror(-ret));
        return ret;
 }
 
-static void oss_post_select(__a_unused struct sched *s,
-               struct task *t)
+static int oss_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_oss_write_data *powd = wn->private_data;
        struct btr_node *btrn = wn->btrn;
        size_t frames, bytes;
        int ret;
        char *data;
+       audio_buf_info abi;
 
-       ret = task_get_notification(t);
+       ret = task_get_notification(wn->task);
        if (ret < 0)
                goto out;
        ret = btr_node_status(btrn, wn->min_iqs, BTR_NT_LEAF);
@@ -175,13 +192,17 @@ static void oss_post_select(__a_unused struct sched *s,
                goto out;
        if (!powd) {
                int32_t rate, ch, format;
+
+               if (sound_device_is_busy())
+                       return 0;
                get_btr_sample_rate(btrn, &rate);
                get_btr_channels(btrn, &ch);
                get_btr_sample_format(btrn, &format);
                ret = oss_init(wn, rate, ch, format);
                if (ret < 0)
                        goto out;
-               return;
+               set_sound_device_busy();
+               return 0;
        }
        btr_merge(btrn, wn->min_iqs);
        bytes = btr_next_buffer(btrn, &data);
@@ -193,51 +214,28 @@ static void oss_post_select(__a_unused struct sched *s,
        ret = 0;
        if (!FD_ISSET(powd->fd, &s->wfds))
                goto out;
+       /* get maximal number of bytes that can be written */
+       ret = ioctl(powd->fd, SNDCTL_DSP_GETOSPACE, &abi);
+       if (ret >= 0) {
+               size_t max_frames = abi.bytes / powd->bytes_per_frame;
+               if (max_frames == 0)
+                       goto out;
+               /* cap number of frames to avoid sound artefacts */
+               frames = PARA_MIN(frames, max_frames);
+       }
        ret = xwrite(powd->fd, data, frames * powd->bytes_per_frame);
        if (ret < 0)
                goto out;
        btr_consume(btrn, ret);
        ret = 0;
 out:
-       t->error = ret;
        if (ret < 0)
                btr_remove_node(&wn->btrn);
+       return ret;
 }
 
-__malloc static void *oss_parse_config_or_die(int argc, char **argv)
-{
-       struct oss_write_args_info *conf = para_calloc(sizeof(*conf));
-
-       /* exits on errors */
-       oss_write_cmdline_parser(argc, argv, conf);
-       return conf;
-}
-
-static void oss_free_config(void *conf)
-{
-       oss_write_cmdline_parser_free(conf);
-}
-
-/**
- * The init function of the oss writer.
- *
- * \param w Pointer to the writer to initialize.
- *
- * \sa struct writer.
- */
-void oss_write_init(struct writer *w)
-{
-       struct oss_write_args_info dummy;
-
-       oss_write_cmdline_parser_init(&dummy);
-       w->close = oss_close;
-       w->pre_select = oss_pre_select;
-       w->post_select = oss_post_select;
-       w->parse_config_or_die = oss_parse_config_or_die;
-       w->free_config = oss_free_config;
-       w->help = (struct ggo_help) {
-               .short_help = oss_write_args_info_help,
-               .detailed_help = oss_write_args_info_detailed_help
-       };
-       oss_write_cmdline_parser_free(&dummy);
-}
+const struct writer lsg_write_cmd_com_oss_user_data = {
+       .pre_select = oss_pre_select,
+       .post_select = oss_post_select,
+       .close = oss_close,
+};