From: Andre Noll <maan@systemlinux.org>
Date: Tue, 29 Dec 2009 23:51:21 +0000 (+0100)
Subject: para_write: Make check for wav header work with btr.
X-Git-Tag: v0.4.2~239
X-Git-Url: http://git.tuebingen.mpg.de/?p=paraslash.git;a=commitdiff_plain;h=e4713d70469e7ca1afd8e8b9a3e67c3764cf3933;hp=5587494468627e20fe622b6055689717262d09ab

para_write: Make check for wav header work with btr.
---

diff --git a/buffer_tree.c b/buffer_tree.c
index 92566745..7b3355a2 100644
--- a/buffer_tree.c
+++ b/buffer_tree.c
@@ -36,6 +36,7 @@ struct btr_node {
 	 */
 	struct list_head input_queue;
 	btr_command_handler execute;
+	void *context;
 };
 
 #define FOR_EACH_CHILD(_tn, _btrn) list_for_each_entry((_tn), \
@@ -47,13 +48,14 @@ struct btr_node {
 	list_for_each_entry_safe((_br), (_tmp), &(_btrn)->input_queue, node)
 
 struct btr_node *btr_new_node(char *name, struct btr_node *parent,
-		btr_command_handler handler)
+		btr_command_handler handler, void *context)
 {
 	struct btr_node *btrn = para_malloc(sizeof(*btrn));
 
 	btrn->name = para_strdup(name);
 	btrn->parent = parent;
 	btrn->execute = handler;
+	btrn->context = context;
 	if (parent)
 		list_add_tail(&btrn->node, &parent->children);
 	INIT_LIST_HEAD(&btrn->children);
@@ -93,14 +95,15 @@ static void btr_drop_buffer_reference(struct btr_buffer_reference *br)
 	}
 }
 
-static void add_btrb_to_children(struct btr_buffer *btrb, struct btr_node *btrn)
+static void add_btrb_to_children(struct btr_buffer *btrb,
+		struct btr_node *btrn, size_t consumed)
 {
 	struct btr_node *ch;
 
 	FOR_EACH_CHILD(ch, btrn) {
 		struct btr_buffer_reference *br = para_malloc(sizeof(*br));
 		br->btrb = btrb;
-		br->consumed = 0;
+		br->consumed = consumed;
 		list_add_tail(&br->node, &ch->input_queue);
 		btrb->refcount++;
 	}
@@ -111,12 +114,12 @@ void btr_add_output(char *buf, size_t size, struct btr_node *btrn)
 	struct btr_buffer *btrb;
 
 	btrb = new_btrb(buf, size);
-	add_btrb_to_children(btrb, btrn);
+	add_btrb_to_children(btrb, btrn, 0);
 }
 
 static void btr_pushdown_br(struct btr_buffer_reference *br, struct btr_node *btrn)
 {
-	add_btrb_to_children(br->btrb, btrn);
+	add_btrb_to_children(br->btrb, btrn, br->consumed);
 	btr_drop_buffer_reference(br);
 }
 
@@ -257,7 +260,7 @@ int btr_exec(struct btr_node *btrn, const char *command, char **value_result)
 		return -ERRNO_TO_PARA_ERROR(EINVAL);
 	if (!btrn->execute)
 		return -ERRNO_TO_PARA_ERROR(ENOTSUP);
-	return btrn->execute(command, value_result);
+	return btrn->execute(btrn, command, value_result);
 }
 
 int btr_exec_up(struct btr_node *btrn, const char *command, char **value_result)
@@ -271,7 +274,7 @@ int btr_exec_up(struct btr_node *btrn, const char *command, char **value_result)
 			return -ERRNO_TO_PARA_ERROR(ENOTSUP);
 		if (!parent->execute)
 			continue;
-		ret = parent->execute(command, value_result);
+		ret = parent->execute(parent, command, value_result);
 		if (ret == -ERRNO_TO_PARA_ERROR(ENOTSUP))
 			continue;
 		if (ret < 0)
@@ -279,3 +282,8 @@ int btr_exec_up(struct btr_node *btrn, const char *command, char **value_result)
 	}
 	return -ERRNO_TO_PARA_ERROR(ENOTSUP);
 }
+
+void *btr_context(struct btr_node *btrn)
+{
+	return btrn->context;
+}
diff --git a/buffer_tree.h b/buffer_tree.h
index 69886c79..27f5da2f 100644
--- a/buffer_tree.h
+++ b/buffer_tree.h
@@ -1,10 +1,11 @@
 
 struct btr_node;
 
-typedef int (*btr_command_handler)(const char *command, char **result);
+typedef int (*btr_command_handler)(struct btr_node *btrn,
+		const char *command, char **result);
 
 struct btr_node *btr_new_node(char *name, struct btr_node *parent,
-		btr_command_handler handler);
+		btr_command_handler handler, void *context);
 void btr_del_node(struct btr_node *btrn);
 void btr_add_output(char *buf, size_t size, struct btr_node *btrn);
 bool btr_no_children(struct btr_node *btrn);
@@ -16,3 +17,5 @@ void btr_consume(struct btr_node *btrn, size_t numbytes);
 int btr_exec(struct btr_node *btrn, const char *command, char **value_result);
 int btr_exec_up(struct btr_node *btrn, const char *command, char **value_result);
 int btr_splice_out_node(struct btr_node *btrn);
+void btr_pushdown(struct btr_node *btrn);
+void *btr_context(struct btr_node *btrn);
diff --git a/error.h b/error.h
index f5fdea64..1a3e6483 100644
--- a/error.h
+++ b/error.h
@@ -387,6 +387,7 @@ extern const char **para_errlist[];
 	PARA_ERROR(WAV_HEADER_SUCCESS, "successfully read wave header"), \
 	PARA_ERROR(NO_DELAY, "no initial delay"), \
 	PARA_ERROR(DELAY_TIMEOUT, "initial delay timeout"), \
+	PARA_ERROR(WRITE_EOF, "end of file"), \
 
 
 #define ALSA_WRITE_ERRORS \
diff --git a/http_recv.c b/http_recv.c
index 59f00d83..cf93076d 100644
--- a/http_recv.c
+++ b/http_recv.c
@@ -215,7 +215,7 @@ static int http_recv_open(struct receiver_node *rn)
 	phd->fd = fd;
 	phd->status = HTTP_CONNECTED;
 	if (conf->buffer_tree_given)
-		rn->btrn = btr_new_node("receiver", NULL, NULL);
+		rn->btrn = btr_new_node("receiver", NULL, NULL, NULL);
 	return 1;
 }
 
diff --git a/recv.c b/recv.c
index 57931943..6f05c47f 100644
--- a/recv.c
+++ b/recv.c
@@ -98,7 +98,7 @@ int main(int argc, char *argv[])
 	r_opened = 1;
 
 	if (conf.buffer_tree_given)
-		sot.btrn = btr_new_node("stdout", rn.btrn, NULL);
+		sot.btrn = btr_new_node("stdout", rn.btrn, NULL, NULL);
 
 	stdout_set_defaults(&sot);
 	sot.bufp = &rn.buf;
diff --git a/write.c b/write.c
index 818175a4..8b0e183f 100644
--- a/write.c
+++ b/write.c
@@ -42,6 +42,23 @@ struct check_wav_task {
 	struct task task;
 };
 
+enum check_wav_state {
+	CWS_NEED_HEADER,
+	CWS_HAVE_HEADER,
+	CWS_NO_HEADER,
+};
+
+struct check_wav_task_btr {
+	int state;
+	/** Number of channels specified in wav header given by \a buf. */
+	unsigned channels;
+	/** Sample rate specified in wav header given by \a buf. */
+	unsigned samplerate;
+	/** The task structure used by the scheduler. */
+	struct task task;
+	struct btr_node *btrn;
+};
+
 /** Delay writing until given time. */
 struct initial_delay_task {
 	/** The time the first data should be written out. */
@@ -103,6 +120,85 @@ out:
 	s->timeout.tv_usec = 1;
 }
 
+static void check_wav_pre_select_btr(__a_unused struct sched *s, struct task *t)
+{
+	struct check_wav_task_btr *cwt = container_of(t, struct check_wav_task_btr, task);
+
+	if (btr_get_input_queue_size(cwt->btrn) < WAV_HEADER_LEN)
+		return;
+	s->timeout.tv_sec = 0;
+	s->timeout.tv_usec = 1;
+}
+
+static int check_wav_exec(struct btr_node *btrn, const char *cmd, char **result)
+{
+	struct check_wav_task_btr *cwt = btr_context(btrn);
+
+	if (!strcmp(cmd, "samplerate")) {
+		if (cwt->state != CWS_HAVE_HEADER)
+			return -ERRNO_TO_PARA_ERROR(ENAVAIL);
+		*result = make_message("%d", cwt->samplerate);
+		return 1;
+	}
+	if (!strcmp(cmd, "channels")) {
+		if (cwt->state != CWS_HAVE_HEADER)
+			return -ERRNO_TO_PARA_ERROR(ENAVAIL);
+		*result = make_message("%d", cwt->samplerate);
+		return 1;
+	}
+	return -ERRNO_TO_PARA_ERROR(ENOTSUP);
+}
+
+static void check_wav_post_select_btr(__a_unused struct sched *s, struct task *t)
+{
+	struct check_wav_task_btr *cwt = container_of(t, struct check_wav_task_btr, task);
+	unsigned char *a;
+	size_t sz = btr_get_input_queue_size(cwt->btrn);
+
+	t->error = 0;
+	if (cwt->state != CWS_NEED_HEADER)
+		goto out;
+	if (sz < WAV_HEADER_LEN) {
+		if (!btr_no_parent(cwt->btrn))
+			return;
+		if (sz != 0) {
+			cwt->state = CWS_NO_HEADER;
+			goto out;
+		}
+		t->error = -E_WRITE_EOF;
+		goto err;
+	}
+	cwt->channels = 2;
+	cwt->samplerate = 44100;
+	btr_next_buffer(cwt->btrn, (char **)&a);
+	if (a[0] != 'R' || a[1] != 'I' || a[2] != 'F' || a[3] != 'F') {
+		PARA_NOTICE_LOG("wav header not found\n");
+		cwt->state = CWS_NO_HEADER;
+		sprintf(t->status, "check wav: no header");
+		goto consume;
+	}
+	PARA_INFO_LOG("found wav header\n");
+	cwt->state = CWS_HAVE_HEADER;
+	sprintf(t->status, "check wav: have header");
+	cwt->channels = (unsigned) a[22];
+	cwt->samplerate = a[24] + (a[25] << 8) + (a[26] << 16) + (a[27] << 24);
+consume:
+	PARA_INFO_LOG("channels: %d, sample rate: %d\n", cwt->channels, cwt->samplerate);
+	btr_consume(cwt->btrn, WAV_HEADER_LEN);
+out:
+	if (sz) {
+		btr_pushdown(cwt->btrn);
+		s->timeout.tv_sec = 0;
+		s->timeout.tv_usec = 1;
+	} else {
+		if (btr_no_parent(cwt->btrn))
+			t->error = -E_WRITE_EOF;
+	}
+err:
+	if (t->error < 0)
+		btr_del_node(cwt->btrn);
+}
+
 static void initial_delay_pre_select(struct sched *s, struct task *t)
 {
 	struct initial_delay_task *idt = container_of(t, struct initial_delay_task, task);
@@ -189,14 +285,22 @@ static int main_btr(struct sched *s)
 	struct writer_node *wn = para_malloc(sizeof(*wn));
 	struct writer *w = writers + DEFAULT_WRITER;
 	int ret;
+	struct check_wav_task_btr _cwt, *cwt = &_cwt;
 
-	sit.btrn = btr_new_node("stdin", NULL /* stdin has no parent */, NULL);
+	sit.btrn = btr_new_node("stdin", NULL /* stdin has no parent */, NULL, NULL);
 	stdin_set_defaults(&sit);
 	register_task(&sit.task);
 
+	cwt->state = CWS_NEED_HEADER;
+	cwt->btrn = btr_new_node("check wav", sit.btrn, check_wav_exec, cwt);
+	sprintf(cwt->task.status, "check wav");
+	cwt->task.pre_select = check_wav_pre_select_btr;
+	cwt->task.post_select = check_wav_post_select_btr;
+	register_task(&cwt->task);
+
 	wn->writer_num = DEFAULT_WRITER;
 	wn->conf = writers[DEFAULT_WRITER].parse_config("-B");
-	wn->btrn = btr_new_node("writer", sit.btrn, NULL);
+	wn->btrn = btr_new_node("writer", cwt->btrn, NULL, NULL);
 	sprintf(wn->task.status, "some writer");
 	w->open(wn);
 	wn->task.post_select = w->post_select_btr;