removed unused sources
Cleaning up artifacts from a merge gone wrong. Also remove the ringbuf library, which is not being used.
This commit is contained in:
Max Kellermann
parent
fb233df7a9
commit
1e0acb2e1a
@ -59,7 +59,6 @@ mpd_headers = \
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playlist.h \
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playlist_save.h \
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replayGain.h \
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ringbuf.h \
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signal_check.h \
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sig_handlers.h \
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song.h \
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@ -138,7 +137,6 @@ mpd_SOURCES = \
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playlist.c \
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playlist_save.c \
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replayGain.c \
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ringbuf.c \
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sig_handlers.c \
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signal_check.c \
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song.c \
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@ -1,151 +0,0 @@
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/* the Music Player Daemon (MPD)
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* Copyright (C) 2003-2007 by Warren Dukes (warren.dukes@gmail.com)
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* This project's homepage is: http://www.musicpd.org
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*
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* This program is free software; you can redistribute it and/or modify
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* it under the terms of the GNU General Public License as published by
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* the Free Software Foundation; either version 2 of the License, or
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* (at your option) any later version.
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*
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* This program is distributed in the hope that it will be useful,
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* but WITHOUT ANY WARRANTY; without even the implied warranty of
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* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
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* GNU General Public License for more details.
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* You should have received a copy of the GNU General Public License
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* along with this program; if not, write to the Free Software
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* Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
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*/
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#include "metadata_pipe.h"
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#include "ringbuf.h"
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#include "decode.h"
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#include "os_compat.h"
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#include "log.h"
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#include "outputBuffer.h"
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#include "gcc.h"
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static struct ringbuf *mp;
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/* Each one of these is a packet inside the metadata pipe */
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struct tag_container {
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float metadata_time;
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uint8_t seq; /* ob.seq_decoder at time of metadata_pipe_send() */
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struct mpd_tag *tag; /* our payload */
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};
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/*
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* We have two readers even though ringbuf was designed for one (locklessly),
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* so we will use a lock to allow readers to safely read. Writing is only
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* done from one thread, so it will never block or clobber.
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*/
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static pthread_mutex_t read_lock = PTHREAD_MUTEX_INITIALIZER;
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static struct mpd_tag *current_tag; /* requires read_lock for both r/w access */
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static void metadata_pipe_finish(void)
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{
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ringbuf_free(mp);
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if (current_tag)
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tag_free(current_tag);
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}
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void init_metadata_pipe(void)
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{
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mp = ringbuf_create(sizeof(struct tag_container) * 16);
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atexit(metadata_pipe_finish);
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}
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void metadata_pipe_send(struct mpd_tag *tag, float metadata_time)
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{
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struct tag_container tc;
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size_t written;
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assert(pthread_equal(pthread_self(), dc.thread));
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if (mpd_unlikely(ringbuf_write_space(mp)
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< sizeof(struct tag_container))) {
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DEBUG("metadata_pipe: insufficient buffer space, dropping\n");
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tag_free(tag);
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return;
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}
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tc.tag = tag;
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tc.metadata_time = metadata_time;
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tc.seq = ob_get_decoder_sequence();
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written = ringbuf_write(mp, &tc, sizeof(struct tag_container));
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assert(written == sizeof(struct tag_container));
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}
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struct mpd_tag * metadata_pipe_recv(void)
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{
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struct tag_container tc;
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size_t r;
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static const size_t uint8_t_max = 255; /* XXX CLEANUP */
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uint8_t expect_seq = ob_get_player_sequence();
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unsigned long current_time = ob_get_elapsed_time();
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struct mpd_tag *tag = NULL;
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if (pthread_mutex_trylock(&read_lock) == EBUSY)
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return NULL;
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retry:
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if (!(r = ringbuf_peek(mp, &tc, sizeof(struct tag_container))))
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goto out;
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assert(r == sizeof(struct tag_container));
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assert(tc.tag);
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if (expect_seq == tc.seq) {
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if (current_time < tc.metadata_time)
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goto out; /* not ready for tag yet */
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if (tag_equal(tc.tag, current_tag)) {
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tag_free(tc.tag);
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ringbuf_read_advance(mp, sizeof(struct tag_container));
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goto out; /* nothing changed, don't bother */
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}
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tag = tag_dup(tc.tag);
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if (current_tag)
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tag_free(current_tag);
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current_tag = tc.tag;
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ringbuf_read_advance(mp, sizeof(struct tag_container));
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} else if (expect_seq > tc.seq ||
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(!expect_seq && tc.seq == uint8_t_max)) {
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DEBUG("metadata_pipe: reader is ahead of writer\n");
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tag_free(tc.tag);
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ringbuf_read_advance(mp, sizeof(struct tag_container));
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goto retry; /* read and skip packets */
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} /* else not ready for tag yet */
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out:
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pthread_mutex_unlock(&read_lock);
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return tag;
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}
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struct mpd_tag *metadata_pipe_current(void)
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{
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struct mpd_tag *tag;
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assert(! pthread_equal(pthread_self(), dc.thread));
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if (pthread_mutex_trylock(&read_lock) == EBUSY)
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return NULL;
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tag = current_tag ? tag_dup(current_tag) : NULL;
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pthread_mutex_unlock(&read_lock);
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return tag;
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}
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void metadata_pipe_clear(void)
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{
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struct tag_container tc;
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size_t r;
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pthread_mutex_lock(&read_lock);
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while ((r = ringbuf_read(mp, &tc, sizeof(struct tag_container)))) {
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assert(r == sizeof(struct tag_container));
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tag_free(tc.tag);
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}
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if (current_tag) {
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tag_free(current_tag);
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current_tag = NULL;
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}
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pthread_mutex_unlock(&read_lock);
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}
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311
src/ringbuf.c
311
src/ringbuf.c
@ -1,311 +0,0 @@
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/*
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* This file is originally from JACK Audio Connection Kit
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*
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* Copyright (C) 2000 Paul Davis
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* Copyright (C) 2003 Rohan Drape
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*
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* This program is free software; you can redistribute it and/or modify
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* it under the terms of the GNU Lesser General Public License as published by
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* the Free Software Foundation; either version 2.1 of the License, or
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* (at your option) any later version.
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*
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* This program is distributed in the hope that it will be useful,
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* but WITHOUT ANY WARRANTY; without even the implied warranty of
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* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
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* GNU Lesser General Public License for more details.
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*
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* You should have received a copy of the GNU Lesser General Public License
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* along with this program; if not, write to the Free Software
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* Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
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*
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* ISO/POSIX C version of Paul Davis's lock free ringbuffer C++ code.
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* This is safe for the case of one read thread and one write thread.
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*/
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#include "ringbuf.h"
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#include "utils.h"
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#include <string.h>
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#define advance_ptr(ptr,cnt,mask) ptr = (ptr + cnt) & mask
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/*
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* Create a new ringbuffer to hold at least `sz' bytes of data. The
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* actual buffer size is rounded up to the next power of two.
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*/
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struct ringbuf *ringbuf_create(size_t sz)
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{
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struct ringbuf *rb = xmalloc(sizeof(struct ringbuf));
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size_t power_of_two;
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for (power_of_two = 1; (size_t)(1 << power_of_two) < sz; power_of_two++)
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/* next power_of_two... */;
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rb->size = 1 << power_of_two;
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rb->size_mask = rb->size;
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rb->size_mask -= 1;
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rb->buf = xmalloc(rb->size);
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ringbuf_reset(rb);
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return rb;
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}
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/* Free all data associated with the ringbuffer `rb'. */
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void ringbuf_free(struct ringbuf * rb)
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{
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free(rb->buf);
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free(rb);
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}
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/* Reset the read and write pointers to zero. This is not thread safe. */
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void ringbuf_reset(struct ringbuf * rb)
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{
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rb->read_ptr = 0;
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rb->write_ptr = 0;
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}
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/* Reset the read and write pointers, thread-safe iff called only by writer */
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void ringbuf_writer_reset(struct ringbuf * rb)
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{
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rb->write_ptr = rb->read_ptr;
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}
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/* Reset the read and write pointers, thread-safe iff called only by reader */
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void ringbuf_reader_reset(struct ringbuf * rb)
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{
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rb->read_ptr = rb->write_ptr;
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}
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/*
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* Return the number of bytes available for reading. This is the
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* number of bytes in front of the read pointer and behind the write
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* pointer.
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*/
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size_t ringbuf_read_space(const struct ringbuf * rb)
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{
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size_t w = rb->write_ptr;
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size_t r = rb->read_ptr;
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if (w > r)
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return w - r;
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else
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return (w - r + rb->size) & rb->size_mask;
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}
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/*
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* Return the number of bytes available for writing. This is the
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* number of bytes in front of the write pointer and behind the read
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* pointer.
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*/
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size_t ringbuf_write_space(const struct ringbuf * rb)
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{
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size_t w = rb->write_ptr;
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size_t r = rb->read_ptr;
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if (w > r)
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return ((r - w + rb->size) & rb->size_mask) - 1;
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else if (w < r)
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return (r - w) - 1;
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else
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return rb->size - 1;
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}
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/*
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* The copying data reader. Copy at most `cnt' bytes from `rb' to
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* `dest'. Returns the actual number of bytes copied.
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*/
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size_t ringbuf_read(struct ringbuf * rb, void *dest, size_t cnt)
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{
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size_t free_cnt;
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size_t cnt2;
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size_t to_read;
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size_t n1, n2;
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if ((free_cnt = ringbuf_read_space(rb)) == 0)
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return 0;
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to_read = cnt > free_cnt ? free_cnt : cnt;
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cnt2 = rb->read_ptr + to_read;
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if (cnt2 > rb->size) {
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n1 = rb->size - rb->read_ptr;
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n2 = cnt2 & rb->size_mask;
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} else {
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n1 = to_read;
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n2 = 0;
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}
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memcpy(dest, rb->buf + rb->read_ptr, n1);
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ringbuf_read_advance(rb, n1);
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if (n2) {
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memcpy((char*)dest + n1, rb->buf + rb->read_ptr, n2);
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ringbuf_read_advance(rb, n2);
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}
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return to_read;
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}
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/*
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* The copying data reader w/o read pointer advance. Copy at most
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* `cnt' bytes from `rb' to `dest'. Returns the actual number of bytes
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* copied.
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*/
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size_t ringbuf_peek(struct ringbuf * rb, void *dest, size_t cnt)
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{
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size_t free_cnt;
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size_t cnt2;
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size_t to_read;
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size_t n1, n2;
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size_t tmp_read_ptr = rb->read_ptr;
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if ((free_cnt = ringbuf_read_space(rb)) == 0)
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return 0;
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to_read = cnt > free_cnt ? free_cnt : cnt;
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cnt2 = tmp_read_ptr + to_read;
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if (cnt2 > rb->size) {
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n1 = rb->size - tmp_read_ptr;
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n2 = cnt2 & rb->size_mask;
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} else {
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n1 = to_read;
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n2 = 0;
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}
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memcpy(dest, rb->buf + tmp_read_ptr, n1);
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advance_ptr(tmp_read_ptr, n1, rb->size_mask);
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if (n2) {
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memcpy((char*)dest + n1, rb->buf + tmp_read_ptr, n2);
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advance_ptr(tmp_read_ptr, n2, rb->size_mask);
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}
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return to_read;
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}
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/*
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* The copying data writer. Copy at most `cnt' bytes to `rb' from
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* `src'. Returns the actual number of bytes copied.
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*/
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size_t ringbuf_write(struct ringbuf * rb, const void *src, size_t cnt)
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{
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size_t free_cnt;
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size_t cnt2;
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size_t to_write;
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size_t n1, n2;
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if ((free_cnt = ringbuf_write_space(rb)) == 0)
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return 0;
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to_write = cnt > free_cnt ? free_cnt : cnt;
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cnt2 = rb->write_ptr + to_write;
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if (cnt2 > rb->size) {
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n1 = rb->size - rb->write_ptr;
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n2 = cnt2 & rb->size_mask;
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} else {
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n1 = to_write;
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n2 = 0;
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}
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memcpy(rb->buf + rb->write_ptr, src, n1);
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ringbuf_write_advance(rb, n1);
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if (n2) {
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memcpy(rb->buf + rb->write_ptr, (const char*)src + n1, n2);
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ringbuf_write_advance(rb, n2);
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}
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return to_write;
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}
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/* Advance the read pointer `cnt' places. */
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void ringbuf_read_advance(struct ringbuf * rb, size_t cnt)
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{
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advance_ptr(rb->read_ptr, cnt, rb->size_mask);
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}
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/* Advance the write pointer `cnt' places. */
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void ringbuf_write_advance(struct ringbuf * rb, size_t cnt)
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{
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advance_ptr(rb->write_ptr, cnt, rb->size_mask);
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}
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/*
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* The non-copying data reader. `vec' is an array of two places. Set
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* the values at `vec' to hold the current readable data at `rb'. If
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* the readable data is in one segment the second segment has zero
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* length.
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*/
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size_t ringbuf_get_read_vector(const struct ringbuf * rb, struct iovec * vec)
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{
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size_t free_cnt;
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size_t cnt2;
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size_t w = rb->write_ptr;
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size_t r = rb->read_ptr;
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if (w > r)
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free_cnt = w - r;
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else
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free_cnt = (w - r + rb->size) & rb->size_mask;
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cnt2 = r + free_cnt;
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if (cnt2 > rb->size) {
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/*
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* Two part vector: the rest of the buffer after the current
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* write ptr, plus some from the start of the buffer.
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*/
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vec[0].iov_base = rb->buf + r;
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vec[0].iov_len = rb->size - r;
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vec[1].iov_base = rb->buf;
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vec[1].iov_len = cnt2 & rb->size_mask;
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} else {
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/* Single part vector: just the rest of the buffer */
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vec[0].iov_base = rb->buf + r;
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vec[0].iov_len = free_cnt;
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vec[1].iov_len = 0;
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}
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return vec[0].iov_len + vec[1].iov_len;
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}
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/*
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* The non-copying data writer. `vec' is an array of two places. Set
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* the values at `vec' to hold the current writeable data at `rb'. If
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* the writeable data is in one segment the second segment has zero
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* length.
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*/
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size_t ringbuf_get_write_vector(const struct ringbuf * rb, struct iovec * vec)
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{
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size_t free_cnt;
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size_t cnt2;
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size_t w = rb->write_ptr;
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size_t r = rb->read_ptr;
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if (w > r)
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free_cnt = ((r - w + rb->size) & rb->size_mask) - 1;
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else if (w < r)
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free_cnt = (r - w) - 1;
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else
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free_cnt = rb->size - 1;
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cnt2 = w + free_cnt;
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if (cnt2 > rb->size) {
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/*
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* Two part vector: the rest of the buffer after the current
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* write ptr, plus some from the start of the buffer.
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*/
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vec[0].iov_base = rb->buf + w;
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vec[0].iov_len = rb->size - w;
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vec[1].iov_base = rb->buf;
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vec[1].iov_len = cnt2 & rb->size_mask;
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} else {
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vec[0].iov_base = rb->buf + w;
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vec[0].iov_len = free_cnt;
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vec[1].iov_len = 0;
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}
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return vec[0].iov_len + vec[1].iov_len;
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}
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227
src/ringbuf.h
227
src/ringbuf.h
@ -1,227 +0,0 @@
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/*
|
||||
* This file is originally from JACK Audio Connection Kit
|
||||
*
|
||||
* Copyright (C) 2000 Paul Davis
|
||||
* Copyright (C) 2003 Rohan Drape
|
||||
*
|
||||
* This program is free software; you can redistribute it and/or modify
|
||||
* it under the terms of the GNU Lesser General Public License as published by
|
||||
* the Free Software Foundation; either version 2.1 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 Lesser General Public License for more details.
|
||||
*
|
||||
* You should have received a copy of the GNU Lesser 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.
|
||||
*/
|
||||
|
||||
#ifndef MPD_RINGBUF_H
|
||||
#define MPD_RINGBUF_H
|
||||
|
||||
#include <stddef.h>
|
||||
#include <sys/uio.h>
|
||||
|
||||
/** @file ringbuf.h
|
||||
*
|
||||
* A set of library functions to make lock-free ringbuffers available
|
||||
* to JACK clients. The `capture_client.c' (in the example_clients
|
||||
* directory) is a fully functioning user of this API.
|
||||
*
|
||||
* The key attribute of a ringbuffer is that it can be safely accessed
|
||||
* by two threads simultaneously -- one reading from the buffer and
|
||||
* the other writing to it -- without using any synchronization or
|
||||
* mutual exclusion primitives. For this to work correctly, there can
|
||||
* only be a single reader and a single writer thread. Their
|
||||
* identities cannot be interchanged.
|
||||
*/
|
||||
|
||||
struct ringbuf {
|
||||
unsigned char *buf;
|
||||
size_t write_ptr;
|
||||
size_t read_ptr;
|
||||
size_t size;
|
||||
size_t size_mask;
|
||||
};
|
||||
|
||||
/**
|
||||
* Allocates a ringbuffer data structure of a specified size. The
|
||||
* caller must arrange for a call to ringbuf_free() to release
|
||||
* the memory associated with the ringbuffer.
|
||||
*
|
||||
* @param sz the ringbuffer size in bytes.
|
||||
*
|
||||
* @return a pointer to a new struct ringbuf, if successful; NULL
|
||||
* otherwise.
|
||||
*/
|
||||
struct ringbuf *ringbuf_create(size_t sz);
|
||||
|
||||
/**
|
||||
* Frees the ringbuffer data structure allocated by an earlier call to
|
||||
* ringbuf_create().
|
||||
*
|
||||
* @param rb a pointer to the ringbuffer structure.
|
||||
*/
|
||||
void ringbuf_free(struct ringbuf * rb);
|
||||
|
||||
/**
|
||||
* Fill a data structure with a description of the current readable
|
||||
* data held in the ringbuffer. This description is returned in a two
|
||||
* element array of struct iovec. Two elements are needed
|
||||
* because the data to be read may be split across the end of the
|
||||
* ringbuffer.
|
||||
*
|
||||
* The first element will always contain a valid @a len field, which
|
||||
* may be zero or greater. If the @a len field is non-zero, then data
|
||||
* can be read in a contiguous fashion using the address given in the
|
||||
* corresponding @a buf field.
|
||||
*
|
||||
* If the second element has a non-zero @a len field, then a second
|
||||
* contiguous stretch of data can be read from the address given in
|
||||
* its corresponding @a buf field.
|
||||
*
|
||||
* @param rb a pointer to the ringbuffer structure.
|
||||
* @param vec a pointer to a 2 element array of struct iovec.
|
||||
*
|
||||
* @return total number of bytes readable into both vec elements
|
||||
*/
|
||||
size_t ringbuf_get_read_vector(const struct ringbuf * rb, struct iovec * vec);
|
||||
|
||||
/**
|
||||
* Fill a data structure with a description of the current writable
|
||||
* space in the ringbuffer. The description is returned in a two
|
||||
* element array of struct iovec. Two elements are needed
|
||||
* because the space available for writing may be split across the end
|
||||
* of the ringbuffer.
|
||||
*
|
||||
* The first element will always contain a valid @a len field, which
|
||||
* may be zero or greater. If the @a len field is non-zero, then data
|
||||
* can be written in a contiguous fashion using the address given in
|
||||
* the corresponding @a buf field.
|
||||
*
|
||||
* If the second element has a non-zero @a len field, then a second
|
||||
* contiguous stretch of data can be written to the address given in
|
||||
* the corresponding @a buf field.
|
||||
*
|
||||
* @param rb a pointer to the ringbuffer structure.
|
||||
* @param vec a pointer to a 2 element array of struct iovec.
|
||||
*
|
||||
* @return total number of bytes writable in both vec elements
|
||||
*/
|
||||
size_t ringbuf_get_write_vector(const struct ringbuf * rb, struct iovec * vec);
|
||||
|
||||
/**
|
||||
* Read data from the ringbuffer.
|
||||
*
|
||||
* @param rb a pointer to the ringbuffer structure.
|
||||
* @param dest a pointer to a buffer where data read from the
|
||||
* ringbuffer will go.
|
||||
* @param cnt the number of bytes to read.
|
||||
*
|
||||
* @return the number of bytes read, which may range from 0 to cnt.
|
||||
*/
|
||||
size_t ringbuf_read(struct ringbuf * rb, void *dest, size_t cnt);
|
||||
|
||||
/**
|
||||
* Read data from the ringbuffer. Opposed to ringbuf_read()
|
||||
* this function does not move the read pointer. Thus it's
|
||||
* a convenient way to inspect data in the ringbuffer in a
|
||||
* continous fashion. The price is that the data is copied
|
||||
* into a user provided buffer. For "raw" non-copy inspection
|
||||
* of the data in the ringbuffer use ringbuf_get_read_vector().
|
||||
*
|
||||
* @param rb a pointer to the ringbuffer structure.
|
||||
* @param dest a pointer to a buffer where data read from the
|
||||
* ringbuffer will go.
|
||||
* @param cnt the number of bytes to read.
|
||||
*
|
||||
* @return the number of bytes read, which may range from 0 to cnt.
|
||||
*/
|
||||
size_t ringbuf_peek(struct ringbuf * rb, void *dest, size_t cnt);
|
||||
|
||||
/**
|
||||
* Advance the read pointer.
|
||||
*
|
||||
* After data have been read from the ringbuffer using the pointers
|
||||
* returned by ringbuf_get_read_vector(), use this function to
|
||||
* advance the buffer pointers, making that space available for future
|
||||
* write operations.
|
||||
*
|
||||
* @param rb a pointer to the ringbuffer structure.
|
||||
* @param cnt the number of bytes read.
|
||||
*/
|
||||
void ringbuf_read_advance(struct ringbuf * rb, size_t cnt);
|
||||
|
||||
/**
|
||||
* Return the number of bytes available for reading.
|
||||
*
|
||||
* @param rb a pointer to the ringbuffer structure.
|
||||
*
|
||||
* @return the number of bytes available to read.
|
||||
*/
|
||||
size_t ringbuf_read_space(const struct ringbuf * rb);
|
||||
|
||||
/**
|
||||
* Reset the read and write pointers, making an empty buffer.
|
||||
*
|
||||
* This is not thread safe.
|
||||
*
|
||||
* @param rb a pointer to the ringbuffer structure.
|
||||
*/
|
||||
void ringbuf_reset(struct ringbuf * rb);
|
||||
|
||||
/**
|
||||
* Reset the write pointer to the read pointer, making an empty buffer.
|
||||
*
|
||||
* This should only be called by the writer
|
||||
*
|
||||
* @param rb a pointer to the ringbuffer structure.
|
||||
*/
|
||||
void ringbuf_writer_reset(struct ringbuf * rb);
|
||||
|
||||
/**
|
||||
* Reset the read pointer to the write pointer, making an empty buffer.
|
||||
*
|
||||
* This should only be called by the reader
|
||||
*
|
||||
* @param rb a pointer to the ringbuffer structure.
|
||||
*/
|
||||
void ringbuf_reader_reset(struct ringbuf * rb);
|
||||
|
||||
/**
|
||||
* Write data into the ringbuffer.
|
||||
*
|
||||
* @param rb a pointer to the ringbuffer structure.
|
||||
* @param src a pointer to the data to be written to the ringbuffer.
|
||||
* @param cnt the number of bytes to write.
|
||||
*
|
||||
* @return the number of bytes write, which may range from 0 to cnt
|
||||
*/
|
||||
size_t ringbuf_write(struct ringbuf * rb, const void *src, size_t cnt);
|
||||
|
||||
/**
|
||||
* Advance the write pointer.
|
||||
*
|
||||
* After data have been written the ringbuffer using the pointers
|
||||
* returned by ringbuf_get_write_vector(), use this function
|
||||
* to advance the buffer pointer, making the data available for future
|
||||
* read operations.
|
||||
*
|
||||
* @param rb a pointer to the ringbuffer structure.
|
||||
* @param cnt the number of bytes written.
|
||||
*/
|
||||
void ringbuf_write_advance(struct ringbuf * rb, size_t cnt);
|
||||
|
||||
/**
|
||||
* Return the number of bytes available for writing.
|
||||
*
|
||||
* @param rb a pointer to the ringbuffer structure.
|
||||
*
|
||||
* @return the amount of free space (in bytes) available for writing.
|
||||
*/
|
||||
size_t ringbuf_write_space(const struct ringbuf * rb);
|
||||
|
||||
#endif /* RINGBUF_H */
|
||||
Loading…
Reference in New Issue
Block a user