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Diffstat (limited to '')
| -rw-r--r-- | src/audioOutputs/audioOutput_fifo.c | 251 |
1 files changed, 251 insertions, 0 deletions
diff --git a/src/audioOutputs/audioOutput_fifo.c b/src/audioOutputs/audioOutput_fifo.c new file mode 100644 index 000000000..58bf2c265 --- /dev/null +++ b/src/audioOutputs/audioOutput_fifo.c @@ -0,0 +1,251 @@ +/* the Music Player Daemon (MPD) + * (c)2003-2006 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 "../audioOutput.h" + +#include <stdlib.h> + +#ifdef HAVE_FIFO + +#include "../conf.h" +#include "../log.h" + +#include <errno.h> +#include <fcntl.h> +#include <string.h> +#include <unistd.h> +#include <sys/stat.h> + +#define FIFO_BUFFER_SIZE 65536 /* pipe capacity on Linux >= 2.6.11 */ + +typedef struct _FifoData { + char *path; + int input; + int output; + int created; +} FifoData; + +static FifoData *newFifoData() +{ + FifoData *ret; + + ret = malloc(sizeof(FifoData)); + + ret->path = NULL; + ret->input = -1; + ret->output = -1; + ret->created = 0; + + return ret; +} + +static void freeFifoData(FifoData *fd) +{ + if (fd->path) free(fd->path); + free(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 info; + + if (stat(fd->path, &info) < 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(info.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)); + 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)); + return -1; + } + + return 0; +} + +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 info; + + if (fd->input >= 0) close(fd->input); + if (fd->output >= 0) close(fd->output); + if (fd->created && (stat(fd->path, &info) == 0)) removeFifo(fd); +} + +static int fifo_initDriver(AudioOutput *audioOutput, ConfigParam *param) +{ + BlockParam *path = NULL; + FifoData *fd; + + if (param) path = getBlockParam(param, "path"); + + if (!path) { + ERROR("No \"path\" parameter specified for fifo output " + "defined at line %i\n", param->line); + exit(EXIT_FAILURE); + } + + if (path->value[0] != '/') { + ERROR("\"path\" parameter for fifo output is not an absolute " + "path at line %i\n", param->line); + exit(EXIT_FAILURE); + } + + fd = newFifoData(); + fd->path = strdup(path->value); + audioOutput->data = fd; + + if (openFifo(fd) < 0) { + freeFifoData(fd); + return -1; + } + + return 0; +} + +static void fifo_finishDriver(AudioOutput *audioOutput) +{ + FifoData *fd; + + fd = audioOutput->data; + closeFifo(fd); + freeFifoData(fd); +} + +static int fifo_openDevice(AudioOutput *audioOutput) +{ + audioOutput->open = 1; + return 0; +} + +static void fifo_dropBufferedAudio(AudioOutput *audioOutput) +{ + FifoData *fd; + char buf[FIFO_BUFFER_SIZE]; + int bytes = 1; + + fd = audioOutput->data; + + while (bytes > 0) 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 void fifo_closeDevice(AudioOutput *audioOutput) +{ + audioOutput->open = 0; +} + +static int fifo_playAudio(AudioOutput *audioOutput, char *playChunk, int size) +{ + FifoData *fd; + int bytes; + int offset = 0; + + fd = audioOutput->data; + + while (1) { + bytes = write(fd->output, &playChunk[offset], size); + if (bytes < 0 && errno == EAGAIN) { + fifo_dropBufferedAudio(audioOutput); + } else if (bytes < 0) { + ERROR("Closing FIFO output \"%s\" due to write error: " + "%s\n", fd->path, strerror(errno)); + fifo_closeDevice(audioOutput); + return -1; + } else if (bytes < size) { + size -= bytes; + offset += bytes; + } else { + break; + } + } + + return 0; +} + +AudioOutputPlugin fifoPlugin = { + "fifo", + NULL, /* testDefaultDeviceFunc */ + fifo_initDriver, + fifo_finishDriver, + fifo_openDevice, + fifo_playAudio, + fifo_dropBufferedAudio, + fifo_closeDevice, + NULL, /* sendMetadataFunc */ +}; + +#else /* HAVE_FIFO */ + +DISABLED_AUDIO_OUTPUT_PLUGIN(fifoPlugin) + +#endif /* HAVE_FIFO */ |