1 files changed, 228 insertions, 0 deletions
diff --git a/src/pipe.c b/src/pipe.c
new file mode 100644
index 000000000..9b8683834
--- /dev/null
+++ b/src/pipe.c
@@ -0,0 +1,228 @@
+/* the Music Player Daemon (MPD)
+ * Copyright (C) 2003-2007 by Warren Dukes (warren.dukes@gmail.com)
+ * This project's homepage is: http://www.musicpd.org
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2 of the License, or
+ * (at your option) any later version.
+ *
+ * This program 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 General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
+ */
+
+#include "pipe.h"
+#include "notify.h"
+#include "utils.h"
+
+#include <assert.h>
+#include <string.h>
+
+struct output_buffer ob;
+
+void
+ob_init(unsigned int size, struct notify *notify)
+{
+	assert(size > 0);
+
+	ob.chunks = xmalloc(size * sizeof(*ob.chunks));
+	ob.size = size;
+	ob.begin = 0;
+	ob.end = 0;
+	ob.lazy = false;
+	ob.notify = notify;
+	ob.chunks[0].chunkSize = 0;
+}
+
+void ob_free(void)
+{
+	assert(ob.chunks != NULL);
+	free(ob.chunks);
+}
+
+void ob_clear(void)
+{
+	ob.end = ob.begin;
+	ob.chunks[ob.end].chunkSize = 0;
+}
+
+/** return the index of the chunk after i */
+static inline unsigned successor(unsigned i)
+{
+	assert(i <= ob.size);
+
+	++i;
+	return i == ob.size ? 0 : i;
+}
+
+/**
+ * Mark the tail chunk as "full" and wake up the player if is waiting
+ * for the decoder.
+ */
+static void output_buffer_expand(unsigned i)
+{
+	int was_empty = ob.notify != NULL && (!ob.lazy || ob_is_empty());
+
+	assert(i == (ob.end + 1) % ob.size);
+	assert(i != ob.end);
+
+	ob.end = i;
+	ob.chunks[i].chunkSize = 0;
+	if (was_empty)
+		/* if the buffer was empty, the player thread might be
+		   waiting for us; wake it up now that another decoded
+		   buffer has become available. */
+		notify_signal(ob.notify);
+}
+
+void ob_flush(void)
+{
+	ob_chunk *chunk = ob_get_chunk(ob.end);
+
+	if (chunk->chunkSize > 0) {
+		unsigned int next = successor(ob.end);
+		if (next == ob.begin)
+			/* all buffers are full; we have to wait for
+			   the player to free one, so don't flush
+			   right now */
+			return;
+
+		output_buffer_expand(next);
+	}
+}
+
+void ob_set_lazy(bool lazy)
+{
+	ob.lazy = lazy;
+}
+
+void ob_shift(void)
+{
+	assert(ob.begin != ob.end);
+	assert(ob.begin < ob.size);
+
+	ob.begin = successor(ob.begin);
+}
+
+unsigned int ob_relative(const unsigned i)
+{
+	if (i >= ob.begin)
+		return i - ob.begin;
+	else
+		return i + ob.size - ob.begin;
+}
+
+unsigned ob_available(void)
+{
+	return ob_relative(ob.end);
+}
+
+int ob_absolute(const unsigned relative)
+{
+	unsigned i, max;
+
+	max = ob.end;
+	if (max < ob.begin)
+		max += ob.size;
+	i = (unsigned)ob.begin + relative;
+	if (i >= max)
+		return -1;
+
+	if (i >= ob.size)
+		i -= ob.size;
+
+	return (int)i;
+}
+
+ob_chunk * ob_get_chunk(const unsigned i)
+{
+	assert(i < ob.size);
+
+	return &ob.chunks[i];
+}
+
+/**
+ * Return the tail chunk which has room for additional data.
+ *
+ * @return the chunk which has room for more data; NULL if there is no
+ * room.
+ */
+static ob_chunk *tail_chunk(float data_time, uint16_t bitRate)
+{
+	const size_t frame_size = audio_format_frame_size(&ob.audioFormat);
+	unsigned int next;
+	ob_chunk *chunk;
+
+	chunk = ob_get_chunk(ob.end);
+	assert(chunk->chunkSize <= sizeof(chunk->data));
+	if (chunk->chunkSize + frame_size > sizeof(chunk->data)) {
+		/* this chunk is full; allocate a new chunk */
+		next = successor(ob.end);
+		if (ob.begin == next)
+			/* no chunks available */
+			return NULL;
+
+		output_buffer_expand(next);
+		chunk = ob_get_chunk(next);
+		assert(chunk->chunkSize == 0);
+	}
+
+	if (chunk->chunkSize == 0) {
+		/* if the chunk is empty, nobody has set bitRate and
+		   times yet */
+
+		chunk->bitRate = bitRate;
+		chunk->times = data_time;
+	}
+
+	return chunk;
+}
+
+size_t ob_append(const void *data0, size_t datalen,
+		 float data_time, uint16_t bitRate)
+{
+	const unsigned char *data = data0;
+	const size_t frame_size = audio_format_frame_size(&ob.audioFormat);
+	size_t ret = 0, dataToSend;
+	ob_chunk *chunk = NULL;
+
+	/* no partial frames allowed */
+	assert((datalen % frame_size) == 0);
+
+	while (datalen) {
+		chunk = tail_chunk(data_time, bitRate);
+		if (chunk == NULL)
+			return ret;
+
+		dataToSend = sizeof(chunk->data) - chunk->chunkSize;
+		if (dataToSend > datalen)
+			dataToSend = datalen;
+
+		/* don't split frames */
+		dataToSend /= frame_size;
+		dataToSend *= frame_size;
+
+		memcpy(chunk->data + chunk->chunkSize, data, dataToSend);
+		chunk->chunkSize += dataToSend;
+		datalen -= dataToSend;
+		data += dataToSend;
+		ret += dataToSend;
+	}
+
+	if (chunk != NULL && chunk->chunkSize == sizeof(chunk->data))
+		ob_flush();
+
+	return ret;
+}
+
+void ob_skip(unsigned num)
+{
+	int i = ob_absolute(num);
+	if (i >= 0)
+		ob.begin = i;
+}