1 files changed, 187 insertions, 0 deletions
diff --git a/src/pulsecore/memblockq.h b/src/pulsecore/memblockq.h
new file mode 100644
index 0000000..96e41cc
--- /dev/null
+++ b/src/pulsecore/memblockq.h
@@ -0,0 +1,187 @@
+#ifndef foomemblockqhfoo
+#define foomemblockqhfoo
+
+/***
+  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 2.1 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, see <http://www.gnu.org/licenses/>.
+***/
+
+#include <sys/types.h>
+#include <inttypes.h>
+
+#include <pulsecore/memblock.h>
+#include <pulsecore/memchunk.h>
+#include <pulse/def.h>
+
+/* A memblockq is a queue of pa_memchunks (yep, the name is not
+ * perfect). It is similar to the ring buffers used by most other
+ * audio software. In contrast to a ring buffer this memblockq data
+ * type doesn't need to copy any data around, it just maintains
+ * references to reference counted memory blocks. */
+
+typedef struct pa_memblockq pa_memblockq;
+
+/* Parameters:
+
+   - name:      name for debugging purposes
+
+   - idx:       start value for both read and write index
+
+   - maxlength: maximum length of queue. If more data is pushed into
+                the queue, the operation will fail. Must not be 0.
+
+   - tlength:   the target length of the queue. Pass 0 for the default.
+
+   - ss:        Sample spec describing the queue contents. Only multiples
+                of the frame size as implied by the sample spec are
+                allowed into the queue or can be popped from it.
+
+   - prebuf:    If the queue runs empty wait until this many bytes are in
+                queue again before passing the first byte out. If set
+                to 0 pa_memblockq_pop() will return a silence memblock
+                if no data is in the queue and will never fail. Pass
+                (size_t) -1 for the default.
+
+   - minreq:    pa_memblockq_pop_missing() will only return values greater
+                than this value. Pass 0 for the default.
+
+   - maxrewind: how many bytes of history to keep in the queue
+
+   - silence:   return this memchunk when reading uninitialized data
+*/
+pa_memblockq* pa_memblockq_new(
+        const char *name,
+        int64_t idx,
+        size_t maxlength,
+        size_t tlength,
+        const pa_sample_spec *sample_spec,
+        size_t prebuf,
+        size_t minreq,
+        size_t maxrewind,
+        pa_memchunk *silence);
+
+void pa_memblockq_free(pa_memblockq*bq);
+
+/* Push a new memory chunk into the queue.  */
+int pa_memblockq_push(pa_memblockq* bq, const pa_memchunk *chunk);
+
+/* Push a new memory chunk into the queue, but filter it through a
+ * pa_mcalign object. Don't mix this with pa_memblockq_seek() unless
+ * you know what you do. */
+int pa_memblockq_push_align(pa_memblockq* bq, const pa_memchunk *chunk);
+
+/* Manipulate the write pointer */
+void pa_memblockq_seek(pa_memblockq *bq, int64_t offset, pa_seek_mode_t seek, bool account);
+
+/* Return a copy of the next memory chunk in the queue. It is not
+ * removed from the queue. There are two reasons this function might
+ * fail: 1. prebuffering is active, 2. queue is empty and no silence
+ * memblock was passed at initialization. If the queue is not empty,
+ * but we're currently at a hole in the queue and no silence memblock
+ * was passed we return the length of the hole in chunk->length. */
+int pa_memblockq_peek(pa_memblockq* bq, pa_memchunk *chunk);
+
+/* Much like pa_memblockq_peek, but guarantees that the returned chunk
+ * will have a length of the block size passed. You must configure a
+ * silence memchunk for this memblockq if you use this call. */
+int pa_memblockq_peek_fixed_size(pa_memblockq *bq, size_t block_size, pa_memchunk *chunk);
+
+/* Drop the specified bytes from the queue. */
+void pa_memblockq_drop(pa_memblockq *bq, size_t length);
+
+/* Rewind the read index. If the history is shorter than the specified length we'll point to silence afterwards. */
+void pa_memblockq_rewind(pa_memblockq *bq, size_t length);
+
+/* Test if the pa_memblockq is currently readable, that is, more data than base */
+bool pa_memblockq_is_readable(pa_memblockq *bq);
+
+/* Return the length of the queue in bytes */
+size_t pa_memblockq_get_length(pa_memblockq *bq);
+
+/* Return the number of bytes that are missing since the last call to
+ * this function, reset the internal counter to 0. */
+size_t pa_memblockq_pop_missing(pa_memblockq *bq);
+
+/* Directly moves the data from the source memblockq into bq */
+int pa_memblockq_splice(pa_memblockq *bq, pa_memblockq *source);
+
+/* Set the queue to silence, set write index to read index */
+void pa_memblockq_flush_write(pa_memblockq *bq, bool account);
+
+/* Set the queue to silence, set write read index to write index*/
+void pa_memblockq_flush_read(pa_memblockq *bq);
+
+/* Ignore prebuf for now */
+void pa_memblockq_prebuf_disable(pa_memblockq *bq);
+
+/* Force prebuf */
+void pa_memblockq_prebuf_force(pa_memblockq *bq);
+
+/* Return the maximum length of the queue in bytes */
+size_t pa_memblockq_get_maxlength(pa_memblockq *bq);
+
+/* Get Target length */
+size_t pa_memblockq_get_tlength(pa_memblockq *bq);
+
+/* Return the prebuffer length in bytes */
+size_t pa_memblockq_get_prebuf(pa_memblockq *bq);
+
+/* Returns the minimal request value */
+size_t pa_memblockq_get_minreq(pa_memblockq *bq);
+
+/* Returns the maximal rewind value */
+size_t pa_memblockq_get_maxrewind(pa_memblockq *bq);
+
+/* Return the base unit in bytes */
+size_t pa_memblockq_get_base(pa_memblockq *bq);
+
+/* Return the current read index */
+int64_t pa_memblockq_get_read_index(pa_memblockq *bq);
+
+/* Return the current write index */
+int64_t pa_memblockq_get_write_index(pa_memblockq *bq);
+
+/* Change metrics. Always call in order. */
+void pa_memblockq_set_maxlength(pa_memblockq *memblockq, size_t maxlength); /* might modify tlength, prebuf, minreq too */
+void pa_memblockq_set_tlength(pa_memblockq *memblockq, size_t tlength); /* might modify minreq, too */
+void pa_memblockq_set_minreq(pa_memblockq *memblockq, size_t minreq); /* might modify prebuf, too */
+void pa_memblockq_set_prebuf(pa_memblockq *memblockq, size_t prebuf);
+void pa_memblockq_set_maxrewind(pa_memblockq *memblockq, size_t maxrewind); /* Set the maximum history size */
+void pa_memblockq_set_silence(pa_memblockq *memblockq, pa_memchunk *silence);
+
+/* Apply the data from pa_buffer_attr */
+void pa_memblockq_apply_attr(pa_memblockq *memblockq, const pa_buffer_attr *a);
+void pa_memblockq_get_attr(pa_memblockq *bq, pa_buffer_attr *a);
+
+/* Call pa_memchunk_will_need() for every chunk in the queue from the current read pointer to the end */
+void pa_memblockq_willneed(pa_memblockq *bq);
+
+/* Check whether the memblockq is completely empty, i.e. no data
+ * neither left nor right of the read pointer, and hence no buffered
+ * data for the future nor data in the backlog. */
+bool pa_memblockq_is_empty(pa_memblockq *bq);
+
+/* Drop everything in the queue, but don't modify the indexes */
+void pa_memblockq_silence(pa_memblockq *bq);
+
+/* Check whether we currently are in prebuf state */
+bool pa_memblockq_prebuf_active(pa_memblockq *bq);
+
+/* Return how many items are currently stored in the queue */
+unsigned pa_memblockq_get_nblocks(pa_memblockq *bq);
+
+#endif