1 files changed, 290 insertions, 0 deletions
diff --git a/src/output/fifo_plugin.c b/src/output/fifo_plugin.c
new file mode 100644
index 000000000..d7eb91ff6
--- /dev/null
+++ b/src/output/fifo_plugin.c
@@ -0,0 +1,290 @@
+/* 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 "../output_api.h"
+
+#ifdef HAVE_FIFO
+
+#include "../log.h"
+#include "../utils.h"
+#include "../timer.h"
+
+#include <sys/types.h>
+#include <sys/stat.h>
+#include <fcntl.h>
+
+#define FIFO_BUFFER_SIZE 65536 /* pipe capacity on Linux >= 2.6.11 */
+
+typedef struct _FifoData {
+	char *path;
+	int input;
+	int output;
+	int created;
+	Timer *timer;
+} FifoData;
+
+static FifoData *newFifoData(void)
+{
+	FifoData *ret;
+
+	ret = xmalloc(sizeof(FifoData));
+
+	ret->path = NULL;
+	ret->input = -1;
+	ret->output = -1;
+	ret->created = 0;
+	ret->timer = NULL;
+	
+	return ret;
+}
+
+static void freeFifoData(FifoData *fd)
+{
+	if (fd->path)
+		free(fd->path);
+
+	if (fd->timer)
+		timer_free(fd->timer);
+
+	free(fd);
+}
+
+static void removeFifo(FifoData *fd)
+{
+	DEBUG("Removing FIFO \"%s\"\n", fd->path);
+
+	if (unlink(fd->path) < 0) {
+		ERROR("Could not remove FIFO \"%s\": %s\n",
+		      fd->path, strerror(errno));
+		return;
+	}
+
+	fd->created = 0;
+}
+
+static void closeFifo(FifoData *fd)
+{
+	struct stat st;
+
+	if (fd->input >= 0) {
+		close(fd->input);
+		fd->input = -1;
+	}
+
+	if (fd->output >= 0) {
+		close(fd->output);
+		fd->output = -1;
+	}
+
+	if (fd->created && (stat(fd->path, &st) == 0))
+		removeFifo(fd);
+}
+
+static int makeFifo(FifoData *fd)
+{
+	if (mkfifo(fd->path, 0666) < 0) {
+		ERROR("Couldn't create FIFO \"%s\": %s\n",
+		      fd->path, strerror(errno));
+		return -1;
+	}
+
+	fd->created = 1;
+
+	return 0;
+}
+
+static int checkFifo(FifoData *fd)
+{
+	struct stat st;
+
+	if (stat(fd->path, &st) < 0) {
+		if (errno == ENOENT) {
+			/* Path doesn't exist */
+			return makeFifo(fd);
+		}
+
+		ERROR("Failed to stat FIFO \"%s\": %s\n",
+		      fd->path, strerror(errno));
+		return -1;
+	}
+
+	if (!S_ISFIFO(st.st_mode)) {
+		ERROR("\"%s\" already exists, but is not a FIFO\n", fd->path);
+		return -1;
+	}
+
+	return 0;
+}
+
+static int openFifo(FifoData *fd)
+{
+	if (checkFifo(fd) < 0)
+		return -1;
+
+	fd->input = open(fd->path, O_RDONLY|O_NONBLOCK);
+	if (fd->input < 0) {
+		ERROR("Could not open FIFO \"%s\" for reading: %s\n",
+		      fd->path, strerror(errno));
+		closeFifo(fd);
+		return -1;
+	}
+
+	fd->output = open(fd->path, O_WRONLY|O_NONBLOCK);
+	if (fd->output < 0) {
+		ERROR("Could not open FIFO \"%s\" for writing: %s\n",
+		      fd->path, strerror(errno));
+		closeFifo(fd);
+		return -1;
+	}
+
+	return 0;
+}
+
+static void *fifo_initDriver(mpd_unused struct audio_output *ao,
+			     mpd_unused const struct audio_format *audio_format,
+			     ConfigParam *param)
+{
+	FifoData *fd;
+	BlockParam *blockParam;
+	char *path;
+
+	blockParam = getBlockParam(param, "path");
+	if (!blockParam) {
+		FATAL("No \"path\" parameter specified for fifo output "
+		      "defined at line %i\n", param->line);
+	}
+
+	path = parsePath(blockParam->value);
+	if (!path) {
+		FATAL("Could not parse \"path\" parameter for fifo output "
+		      "at line %i\n", blockParam->line);
+	}
+
+	fd = newFifoData();
+	fd->path = path;
+
+	if (openFifo(fd) < 0) {
+		freeFifoData(fd);
+		return NULL;
+	}
+
+	return fd;
+}
+
+static void fifo_finishDriver(void *data)
+{
+	FifoData *fd = (FifoData *)data;
+
+	closeFifo(fd);
+	freeFifoData(fd);
+}
+
+static int fifo_openDevice(void *data,
+			   struct audio_format *audio_format)
+{
+	FifoData *fd = (FifoData *)data;
+
+	if (fd->timer)
+		timer_free(fd->timer);
+
+	fd->timer = timer_new(audio_format);
+
+	return 0;
+}
+
+static void fifo_closeDevice(void *data)
+{
+	FifoData *fd = (FifoData *)data;
+
+	if (fd->timer) {
+		timer_free(fd->timer);
+		fd->timer = NULL;
+	}
+}
+
+static void fifo_dropBufferedAudio(void *data)
+{
+	FifoData *fd = (FifoData *)data;
+	char buf[FIFO_BUFFER_SIZE];
+	int bytes = 1;
+
+	timer_reset(fd->timer);
+
+	while (bytes > 0 && errno != EINTR)
+		bytes = read(fd->input, buf, FIFO_BUFFER_SIZE);
+
+	if (bytes < 0 && errno != EAGAIN) {
+		WARNING("Flush of FIFO \"%s\" failed: %s\n",
+		        fd->path, strerror(errno));
+	}
+}
+
+static int fifo_playAudio(void *data,
+			  const char *playChunk, size_t size)
+{
+	FifoData *fd = (FifoData *)data;
+	size_t offset = 0;
+	ssize_t bytes;
+
+	if (!fd->timer->started)
+		timer_start(fd->timer);
+	else
+		timer_sync(fd->timer);
+
+	timer_add(fd->timer, size);
+
+	while (size) {
+		bytes = write(fd->output, playChunk + offset, size);
+		if (bytes < 0) {
+			switch (errno) {
+			case EAGAIN:
+				/* The pipe is full, so empty it */
+				fifo_dropBufferedAudio(fd);
+				continue;
+			case EINTR:
+				continue;
+			}
+
+			ERROR("Closing FIFO output \"%s\" due to write error: "
+			      "%s\n", fd->path, strerror(errno));
+			fifo_closeDevice(fd);
+			return -1;
+		}
+
+		size -= bytes;
+		offset += bytes;
+	}
+
+	return 0;
+}
+
+const struct audio_output_plugin fifoPlugin = {
+	.name = "fifo",
+	.init = fifo_initDriver,
+	.finish = fifo_finishDriver,
+	.open = fifo_openDevice,
+	.play = fifo_playAudio,
+	.cancel = fifo_dropBufferedAudio,
+	.close = fifo_closeDevice,
+};
+
+#else /* HAVE_FIFO */
+
+DISABLED_AUDIO_OUTPUT_PLUGIN(fifoPlugin)
+
+#endif /* !HAVE_FIFO */