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-rw-r--r--src/pulsecore/memblockq.c739
1 files changed, 739 insertions, 0 deletions
diff --git a/src/pulsecore/memblockq.c b/src/pulsecore/memblockq.c
new file mode 100644
index 00000000..8247feab
--- /dev/null
+++ b/src/pulsecore/memblockq.c
@@ -0,0 +1,739 @@
+/* $Id$ */
+
+/***
+ This file is part of PulseAudio.
+
+ Copyright 2004-2006 Lennart Poettering
+
+ PulseAudio 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 of the License,
+ or (at your option) any later version.
+
+ PulseAudio 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 Lesser General Public License
+ along with PulseAudio; if not, write to the Free Software
+ Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307
+ USA.
+***/
+
+#ifdef HAVE_CONFIG_H
+#include <config.h>
+#endif
+
+#include <sys/time.h>
+#include <time.h>
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+
+#include <pulse/xmalloc.h>
+
+#include <pulsecore/log.h>
+#include <pulsecore/mcalign.h>
+#include <pulsecore/macro.h>
+#include <pulsecore/flist.h>
+
+#include "memblockq.h"
+
+struct list_item {
+ struct list_item *next, *prev;
+ int64_t index;
+ pa_memchunk chunk;
+};
+
+PA_STATIC_FLIST_DECLARE(list_items, 0, pa_xfree);
+
+struct pa_memblockq {
+ struct list_item *blocks, *blocks_tail;
+ unsigned n_blocks;
+ size_t maxlength, tlength, base, prebuf, minreq;
+ int64_t read_index, write_index;
+ pa_bool_t in_prebuf;
+ pa_memblock *silence;
+ pa_mcalign *mcalign;
+ int64_t missing;
+ size_t requested;
+};
+
+pa_memblockq* pa_memblockq_new(
+ int64_t idx,
+ size_t maxlength,
+ size_t tlength,
+ size_t base,
+ size_t prebuf,
+ size_t minreq,
+ pa_memblock *silence) {
+
+ pa_memblockq* bq;
+
+ pa_assert(base > 0);
+
+ bq = pa_xnew(pa_memblockq, 1);
+ bq->blocks = bq->blocks_tail = NULL;
+ bq->n_blocks = 0;
+
+ bq->base = base;
+ bq->read_index = bq->write_index = idx;
+
+ pa_log_debug("memblockq requested: maxlength=%lu, tlength=%lu, base=%lu, prebuf=%lu, minreq=%lu",
+ (unsigned long) maxlength, (unsigned long) tlength, (unsigned long) base, (unsigned long) prebuf, (unsigned long) minreq);
+
+ bq->missing = bq->requested = bq->maxlength = bq->tlength = bq->prebuf = bq->minreq = 0;
+ bq->in_prebuf = TRUE;
+
+ pa_memblockq_set_maxlength(bq, maxlength);
+ pa_memblockq_set_tlength(bq, tlength);
+ pa_memblockq_set_prebuf(bq, prebuf);
+ pa_memblockq_set_minreq(bq, minreq);
+
+ pa_log_debug("memblockq sanitized: maxlength=%lu, tlength=%lu, base=%lu, prebuf=%lu, minreq=%lu",
+ (unsigned long)bq->maxlength, (unsigned long)bq->tlength, (unsigned long)bq->base, (unsigned long)bq->prebuf, (unsigned long)bq->minreq);
+
+ bq->silence = silence ? pa_memblock_ref(silence) : NULL;
+ bq->mcalign = NULL;
+
+ return bq;
+}
+
+void pa_memblockq_free(pa_memblockq* bq) {
+ pa_assert(bq);
+
+ pa_memblockq_flush(bq);
+
+ if (bq->silence)
+ pa_memblock_unref(bq->silence);
+
+ if (bq->mcalign)
+ pa_mcalign_free(bq->mcalign);
+
+ pa_xfree(bq);
+}
+
+static void drop_block(pa_memblockq *bq, struct list_item *q) {
+ pa_assert(bq);
+ pa_assert(q);
+
+ pa_assert(bq->n_blocks >= 1);
+
+ if (q->prev)
+ q->prev->next = q->next;
+ else
+ bq->blocks = q->next;
+
+ if (q->next)
+ q->next->prev = q->prev;
+ else
+ bq->blocks_tail = q->prev;
+
+ pa_memblock_unref(q->chunk.memblock);
+
+ if (pa_flist_push(PA_STATIC_FLIST_GET(list_items), q) < 0)
+ pa_xfree(q);
+
+ bq->n_blocks--;
+}
+
+static pa_bool_t can_push(pa_memblockq *bq, size_t l) {
+ int64_t end;
+
+ pa_assert(bq);
+
+ if (bq->read_index > bq->write_index) {
+ size_t d = bq->read_index - bq->write_index;
+
+ if (l > d)
+ l -= d;
+ else
+ return TRUE;
+ }
+
+ end = bq->blocks_tail ? bq->blocks_tail->index + bq->blocks_tail->chunk.length : 0;
+
+ /* Make sure that the list doesn't get too long */
+ if (bq->write_index + (int64_t)l > end)
+ if (bq->write_index + l - bq->read_index > bq->maxlength)
+ return FALSE;
+
+ return TRUE;
+}
+
+int pa_memblockq_push(pa_memblockq* bq, const pa_memchunk *uchunk) {
+ struct list_item *q, *n;
+ pa_memchunk chunk;
+ int64_t old, delta;
+
+ pa_assert(bq);
+ pa_assert(uchunk);
+ pa_assert(uchunk->memblock);
+ pa_assert(uchunk->length > 0);
+ pa_assert(uchunk->index + uchunk->length <= pa_memblock_get_length(uchunk->memblock));
+
+ if (uchunk->length % bq->base)
+ return -1;
+
+ if (!can_push(bq, uchunk->length))
+ return -1;
+
+ old = bq->write_index;
+ chunk = *uchunk;
+
+ if (bq->read_index > bq->write_index) {
+
+ /* We currently have a buffer underflow, we need to drop some
+ * incoming data */
+
+ size_t d = bq->read_index - bq->write_index;
+
+ if (chunk.length > d) {
+ chunk.index += d;
+ chunk.length -= d;
+ bq->write_index += d;
+ } else {
+ /* We drop the incoming data completely */
+ bq->write_index += chunk.length;
+ goto finish;
+ }
+ }
+
+ /* We go from back to front to look for the right place to add
+ * this new entry. Drop data we will overwrite on the way */
+
+ q = bq->blocks_tail;
+ while (q) {
+
+ if (bq->write_index >= q->index + (int64_t) q->chunk.length)
+ /* We found the entry where we need to place the new entry immediately after */
+ break;
+ else if (bq->write_index + (int64_t) chunk.length <= q->index) {
+ /* This entry isn't touched at all, let's skip it */
+ q = q->prev;
+ } else if (bq->write_index <= q->index &&
+ bq->write_index + chunk.length >= q->index + q->chunk.length) {
+
+ /* This entry is fully replaced by the new entry, so let's drop it */
+
+ struct list_item *p;
+ p = q;
+ q = q->prev;
+ drop_block(bq, p);
+ } else if (bq->write_index >= q->index) {
+ /* The write index points into this memblock, so let's
+ * truncate or split it */
+
+ if (bq->write_index + chunk.length < q->index + q->chunk.length) {
+
+ /* We need to save the end of this memchunk */
+ struct list_item *p;
+ size_t d;
+
+ /* Create a new list entry for the end of thie memchunk */
+ if (!(p = pa_flist_pop(PA_STATIC_FLIST_GET(list_items))))
+ p = pa_xnew(struct list_item, 1);
+
+ p->chunk = q->chunk;
+ pa_memblock_ref(p->chunk.memblock);
+
+ /* Calculate offset */
+ d = bq->write_index + chunk.length - q->index;
+ pa_assert(d > 0);
+
+ /* Drop it from the new entry */
+ p->index = q->index + d;
+ p->chunk.length -= d;
+
+ /* Add it to the list */
+ p->prev = q;
+ if ((p->next = q->next))
+ q->next->prev = p;
+ else
+ bq->blocks_tail = p;
+ q->next = p;
+
+ bq->n_blocks++;
+ }
+
+ /* Truncate the chunk */
+ if (!(q->chunk.length = bq->write_index - q->index)) {
+ struct list_item *p;
+ p = q;
+ q = q->prev;
+ drop_block(bq, p);
+ }
+
+ /* We had to truncate this block, hence we're now at the right position */
+ break;
+ } else {
+ size_t d;
+
+ pa_assert(bq->write_index + (int64_t)chunk.length > q->index &&
+ bq->write_index + (int64_t)chunk.length < q->index + (int64_t)q->chunk.length &&
+ bq->write_index < q->index);
+
+ /* The job overwrites the current entry at the end, so let's drop the beginning of this entry */
+
+ d = bq->write_index + chunk.length - q->index;
+ q->index += d;
+ q->chunk.index += d;
+ q->chunk.length -= d;
+
+ q = q->prev;
+ }
+ }
+
+ if (q) {
+ pa_assert(bq->write_index >= q->index + (int64_t)q->chunk.length);
+ pa_assert(!q->next || (bq->write_index + (int64_t)chunk.length <= q->next->index));
+
+ /* Try to merge memory blocks */
+
+ if (q->chunk.memblock == chunk.memblock &&
+ q->chunk.index + (int64_t)q->chunk.length == chunk.index &&
+ bq->write_index == q->index + (int64_t)q->chunk.length) {
+
+ q->chunk.length += chunk.length;
+ bq->write_index += chunk.length;
+ goto finish;
+ }
+ } else
+ pa_assert(!bq->blocks || (bq->write_index + (int64_t)chunk.length <= bq->blocks->index));
+
+ if (!(n = pa_flist_pop(PA_STATIC_FLIST_GET(list_items))))
+ n = pa_xnew(struct list_item, 1);
+
+ n->chunk = chunk;
+ pa_memblock_ref(n->chunk.memblock);
+ n->index = bq->write_index;
+ bq->write_index += n->chunk.length;
+
+ n->next = q ? q->next : bq->blocks;
+ n->prev = q;
+
+ if (n->next)
+ n->next->prev = n;
+ else
+ bq->blocks_tail = n;
+
+ if (n->prev)
+ n->prev->next = n;
+ else
+ bq->blocks = n;
+
+ bq->n_blocks++;
+
+finish:
+
+ delta = bq->write_index - old;
+
+ if (delta >= bq->requested) {
+ delta -= bq->requested;
+ bq->requested = 0;
+ } else {
+ bq->requested -= delta;
+ delta = 0;
+ }
+
+ bq->missing -= delta;
+
+ return 0;
+}
+
+static pa_bool_t memblockq_check_prebuf(pa_memblockq *bq) {
+ pa_assert(bq);
+
+ if (bq->in_prebuf) {
+
+ if (pa_memblockq_get_length(bq) < bq->prebuf)
+ return TRUE;
+
+ bq->in_prebuf = FALSE;
+ return FALSE;
+ } else {
+
+ if (bq->prebuf > 0 && bq->read_index >= bq->write_index) {
+ bq->in_prebuf = TRUE;
+ return TRUE;
+ }
+
+ return FALSE;
+ }
+}
+
+int pa_memblockq_peek(pa_memblockq* bq, pa_memchunk *chunk) {
+ pa_assert(bq);
+ pa_assert(chunk);
+
+ /* We need to pre-buffer */
+ if (memblockq_check_prebuf(bq))
+ return -1;
+
+ /* Do we need to spit out silence? */
+ if (!bq->blocks || bq->blocks->index > bq->read_index) {
+
+ size_t length;
+
+ /* How much silence shall we return? */
+ length = bq->blocks ? bq->blocks->index - bq->read_index : 0;
+
+ /* We need to return silence, since no data is yet available */
+ if (bq->silence) {
+ chunk->memblock = pa_memblock_ref(bq->silence);
+
+ if (!length || length > pa_memblock_get_length(chunk->memblock))
+ length = pa_memblock_get_length(chunk->memblock);
+
+ chunk->length = length;
+ } else {
+
+ /* If the memblockq is empty, return -1, otherwise return
+ * the time to sleep */
+ if (!bq->blocks)
+ return -1;
+
+ chunk->memblock = NULL;
+ chunk->length = length;
+ }
+
+ chunk->index = 0;
+ return 0;
+ }
+
+ /* Ok, let's pass real data to the caller */
+ pa_assert(bq->blocks->index == bq->read_index);
+
+ *chunk = bq->blocks->chunk;
+ pa_memblock_ref(chunk->memblock);
+
+ return 0;
+}
+
+void pa_memblockq_drop(pa_memblockq *bq, size_t length) {
+ int64_t old, delta;
+ pa_assert(bq);
+ pa_assert(length % bq->base == 0);
+
+ old = bq->read_index;
+
+ while (length > 0) {
+
+ /* Do not drop any data when we are in prebuffering mode */
+ if (memblockq_check_prebuf(bq))
+ break;
+
+ if (bq->blocks) {
+ size_t d;
+
+ pa_assert(bq->blocks->index >= bq->read_index);
+
+ d = (size_t) (bq->blocks->index - bq->read_index);
+
+ if (d >= length) {
+ /* The first block is too far in the future */
+
+ bq->read_index += length;
+ break;
+ } else {
+
+ length -= d;
+ bq->read_index += d;
+ }
+
+ pa_assert(bq->blocks->index == bq->read_index);
+
+ if (bq->blocks->chunk.length <= length) {
+ /* We need to drop the full block */
+
+ length -= bq->blocks->chunk.length;
+ bq->read_index += bq->blocks->chunk.length;
+
+ drop_block(bq, bq->blocks);
+ } else {
+ /* Only the start of this block needs to be dropped */
+
+ bq->blocks->chunk.index += length;
+ bq->blocks->chunk.length -= length;
+ bq->blocks->index += length;
+ bq->read_index += length;
+ break;
+ }
+
+ } else {
+
+ /* The list is empty, there's nothing we could drop */
+ bq->read_index += length;
+ break;
+ }
+ }
+
+ delta = bq->read_index - old;
+ bq->missing += delta;
+}
+
+int pa_memblockq_is_readable(pa_memblockq *bq) {
+ pa_assert(bq);
+
+ if (memblockq_check_prebuf(bq))
+ return 0;
+
+ if (pa_memblockq_get_length(bq) <= 0)
+ return 0;
+
+ return 1;
+}
+
+size_t pa_memblockq_get_length(pa_memblockq *bq) {
+ pa_assert(bq);
+
+ if (bq->write_index <= bq->read_index)
+ return 0;
+
+ return (size_t) (bq->write_index - bq->read_index);
+}
+
+size_t pa_memblockq_missing(pa_memblockq *bq) {
+ size_t l;
+ pa_assert(bq);
+
+ if ((l = pa_memblockq_get_length(bq)) >= bq->tlength)
+ return 0;
+
+ l = bq->tlength - l;
+
+ return l >= bq->minreq ? l : 0;
+}
+
+size_t pa_memblockq_get_minreq(pa_memblockq *bq) {
+ pa_assert(bq);
+
+ return bq->minreq;
+}
+
+void pa_memblockq_seek(pa_memblockq *bq, int64_t offset, pa_seek_mode_t seek) {
+ int64_t old, delta;
+ pa_assert(bq);
+
+ old = bq->write_index;
+
+ switch (seek) {
+ case PA_SEEK_RELATIVE:
+ bq->write_index += offset;
+ break;
+ case PA_SEEK_ABSOLUTE:
+ bq->write_index = offset;
+ break;
+ case PA_SEEK_RELATIVE_ON_READ:
+ bq->write_index = bq->read_index + offset;
+ break;
+ case PA_SEEK_RELATIVE_END:
+ bq->write_index = (bq->blocks_tail ? bq->blocks_tail->index + (int64_t) bq->blocks_tail->chunk.length : bq->read_index) + offset;
+ break;
+ default:
+ pa_assert_not_reached();
+ }
+
+ delta = bq->write_index - old;
+
+ if (delta >= bq->requested) {
+ delta -= bq->requested;
+ bq->requested = 0;
+ } else if (delta >= 0) {
+ bq->requested -= delta;
+ delta = 0;
+ }
+
+ bq->missing -= delta;
+}
+
+void pa_memblockq_flush(pa_memblockq *bq) {
+ int64_t old, delta;
+ pa_assert(bq);
+
+ while (bq->blocks)
+ drop_block(bq, bq->blocks);
+
+ pa_assert(bq->n_blocks == 0);
+
+ old = bq->write_index;
+ bq->write_index = bq->read_index;
+
+ pa_memblockq_prebuf_force(bq);
+
+ delta = bq->write_index - old;
+
+ if (delta > bq->requested) {
+ delta -= bq->requested;
+ bq->requested = 0;
+ } else if (delta >= 0) {
+ bq->requested -= delta;
+ delta = 0;
+ }
+
+ bq->missing -= delta;
+}
+
+size_t pa_memblockq_get_tlength(pa_memblockq *bq) {
+ pa_assert(bq);
+
+ return bq->tlength;
+}
+
+int64_t pa_memblockq_get_read_index(pa_memblockq *bq) {
+ pa_assert(bq);
+ return bq->read_index;
+}
+
+int64_t pa_memblockq_get_write_index(pa_memblockq *bq) {
+ pa_assert(bq);
+ return bq->write_index;
+}
+
+int pa_memblockq_push_align(pa_memblockq* bq, const pa_memchunk *chunk) {
+ pa_memchunk rchunk;
+
+ pa_assert(bq);
+ pa_assert(chunk);
+
+ if (bq->base == 1)
+ return pa_memblockq_push(bq, chunk);
+
+ if (!bq->mcalign)
+ bq->mcalign = pa_mcalign_new(bq->base);
+
+ if (!can_push(bq, pa_mcalign_csize(bq->mcalign, chunk->length)))
+ return -1;
+
+ pa_mcalign_push(bq->mcalign, chunk);
+
+ while (pa_mcalign_pop(bq->mcalign, &rchunk) >= 0) {
+ int r;
+ r = pa_memblockq_push(bq, &rchunk);
+ pa_memblock_unref(rchunk.memblock);
+
+ if (r < 0)
+ return -1;
+ }
+
+ return 0;
+}
+
+void pa_memblockq_shorten(pa_memblockq *bq, size_t length) {
+ size_t l;
+ pa_assert(bq);
+
+ l = pa_memblockq_get_length(bq);
+
+ if (l > length)
+ pa_memblockq_drop(bq, l - length);
+}
+
+void pa_memblockq_prebuf_disable(pa_memblockq *bq) {
+ pa_assert(bq);
+
+ bq->in_prebuf = FALSE;
+}
+
+void pa_memblockq_prebuf_force(pa_memblockq *bq) {
+ pa_assert(bq);
+
+ if (!bq->in_prebuf && bq->prebuf > 0)
+ bq->in_prebuf = TRUE;
+}
+
+size_t pa_memblockq_get_maxlength(pa_memblockq *bq) {
+ pa_assert(bq);
+
+ return bq->maxlength;
+}
+
+size_t pa_memblockq_get_prebuf(pa_memblockq *bq) {
+ pa_assert(bq);
+
+ return bq->prebuf;
+}
+
+size_t pa_memblockq_pop_missing(pa_memblockq *bq) {
+ size_t l;
+
+ pa_assert(bq);
+
+/* pa_log("pop: %lli", bq->missing); */
+
+ if (bq->missing <= 0)
+ return 0;
+
+ l = (size_t) bq->missing;
+ bq->missing = 0;
+ bq->requested += l;
+
+ return l;
+}
+
+void pa_memblockq_set_maxlength(pa_memblockq *bq, size_t maxlength) {
+ pa_assert(bq);
+
+ bq->maxlength = ((maxlength+bq->base-1)/bq->base)*bq->base;
+
+ if (bq->maxlength < bq->base)
+ bq->maxlength = bq->base;
+
+ if (bq->tlength > bq->maxlength)
+ pa_memblockq_set_tlength(bq, bq->maxlength);
+
+ if (bq->prebuf > bq->maxlength)
+ pa_memblockq_set_prebuf(bq, bq->maxlength);
+}
+
+void pa_memblockq_set_tlength(pa_memblockq *bq, size_t tlength) {
+ size_t old_tlength;
+ pa_assert(bq);
+
+ old_tlength = bq->tlength;
+
+ if (tlength <= 0)
+ tlength = bq->maxlength;
+
+ bq->tlength = ((tlength+bq->base-1)/bq->base)*bq->base;
+
+ if (bq->tlength > bq->maxlength)
+ bq->tlength = bq->maxlength;
+
+ if (bq->minreq > bq->tlength - bq->prebuf)
+ pa_memblockq_set_minreq(bq, bq->tlength - bq->prebuf);
+
+ bq->missing += (int64_t) bq->tlength - (int64_t) old_tlength;
+}
+
+void pa_memblockq_set_prebuf(pa_memblockq *bq, size_t prebuf) {
+ pa_assert(bq);
+
+ bq->prebuf = (prebuf == (size_t) -1) ? bq->tlength/2 : prebuf;
+ bq->prebuf = ((bq->prebuf+bq->base-1)/bq->base)*bq->base;
+
+ if (prebuf > 0 && bq->prebuf < bq->base)
+ bq->prebuf = bq->base;
+
+ if (bq->prebuf > bq->maxlength)
+ bq->prebuf = bq->maxlength;
+
+ if (bq->prebuf <= 0 || pa_memblockq_get_length(bq) >= bq->prebuf)
+ bq->in_prebuf = FALSE;
+
+ if (bq->minreq > bq->tlength - bq->prebuf)
+ pa_memblockq_set_minreq(bq, bq->tlength - bq->prebuf);
+}
+
+void pa_memblockq_set_minreq(pa_memblockq *bq, size_t minreq) {
+ pa_assert(bq);
+
+ bq->minreq = (minreq/bq->base)*bq->base;
+
+ if (bq->minreq > bq->tlength - bq->prebuf)
+ bq->minreq = bq->tlength - bq->prebuf;
+
+ if (bq->minreq < bq->base)
+ bq->minreq = bq->base;
+}
generated by cgit (git 2.34.1) at 2025-07-13 06:29:14 +0000