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-rw-r--r--src/ringbuf.c311
1 files changed, 0 insertions, 311 deletions
diff --git a/src/ringbuf.c b/src/ringbuf.c
deleted file mode 100644
index e99f26fc6..000000000
--- a/src/ringbuf.c
+++ /dev/null
@@ -1,311 +0,0 @@
-/*
- * 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.
- *
- * ISO/POSIX C version of Paul Davis's lock free ringbuffer C++ code.
- * This is safe for the case of one read thread and one write thread.
- */
-
-#include "ringbuf.h"
-#include "utils.h"
-
-#include <string.h>
-
-#define advance_ptr(ptr,cnt,mask) ptr = (ptr + cnt) & mask
-
-/*
- * Create a new ringbuffer to hold at least `sz' bytes of data. The
- * actual buffer size is rounded up to the next power of two.
- */
-struct ringbuf *ringbuf_create(size_t sz)
-{
- struct ringbuf *rb = xmalloc(sizeof(struct ringbuf));
- size_t power_of_two;
-
- for (power_of_two = 1; (size_t)(1 << power_of_two) < sz; power_of_two++)
- /* next power_of_two... */;
-
- rb->size = 1 << power_of_two;
- rb->size_mask = rb->size;
- rb->size_mask -= 1;
- rb->buf = xmalloc(rb->size);
- ringbuf_reset(rb);
-
- return rb;
-}
-
-/* Free all data associated with the ringbuffer `rb'. */
-void ringbuf_free(struct ringbuf * rb)
-{
- free(rb->buf);
- free(rb);
-}
-
-/* Reset the read and write pointers to zero. This is not thread safe. */
-void ringbuf_reset(struct ringbuf * rb)
-{
- rb->read_ptr = 0;
- rb->write_ptr = 0;
-}
-
-/* Reset the read and write pointers, thread-safe iff called only by writer */
-void ringbuf_writer_reset(struct ringbuf * rb)
-{
- rb->write_ptr = rb->read_ptr;
-}
-
-/* Reset the read and write pointers, thread-safe iff called only by reader */
-void ringbuf_reader_reset(struct ringbuf * rb)
-{
- rb->read_ptr = rb->write_ptr;
-}
-
-/*
- * Return the number of bytes available for reading. This is the
- * number of bytes in front of the read pointer and behind the write
- * pointer.
- */
-size_t ringbuf_read_space(const struct ringbuf * rb)
-{
- size_t w = rb->write_ptr;
- size_t r = rb->read_ptr;
-
- if (w > r)
- return w - r;
- else
- return (w - r + rb->size) & rb->size_mask;
-}
-
-/*
- * Return the number of bytes available for writing. This is the
- * number of bytes in front of the write pointer and behind the read
- * pointer.
- */
-size_t ringbuf_write_space(const struct ringbuf * rb)
-{
- size_t w = rb->write_ptr;
- size_t r = rb->read_ptr;
-
- if (w > r)
- return ((r - w + rb->size) & rb->size_mask) - 1;
- else if (w < r)
- return (r - w) - 1;
- else
- return rb->size - 1;
-}
-
-/*
- * The copying data reader. Copy at most `cnt' bytes from `rb' to
- * `dest'. Returns the actual number of bytes copied.
- */
-size_t ringbuf_read(struct ringbuf * rb, void *dest, size_t cnt)
-{
- size_t free_cnt;
- size_t cnt2;
- size_t to_read;
- size_t n1, n2;
-
- if ((free_cnt = ringbuf_read_space(rb)) == 0)
- return 0;
-
- to_read = cnt > free_cnt ? free_cnt : cnt;
- cnt2 = rb->read_ptr + to_read;
-
- if (cnt2 > rb->size) {
- n1 = rb->size - rb->read_ptr;
- n2 = cnt2 & rb->size_mask;
- } else {
- n1 = to_read;
- n2 = 0;
- }
-
- memcpy(dest, rb->buf + rb->read_ptr, n1);
- ringbuf_read_advance(rb, n1);
-
- if (n2) {
- memcpy((char*)dest + n1, rb->buf + rb->read_ptr, n2);
- ringbuf_read_advance(rb, n2);
- }
-
- return to_read;
-}
-
-/*
- * The copying data reader w/o read pointer advance. Copy at most
- * `cnt' bytes from `rb' to `dest'. Returns the actual number of bytes
- * copied.
- */
-size_t ringbuf_peek(struct ringbuf * rb, void *dest, size_t cnt)
-{
- size_t free_cnt;
- size_t cnt2;
- size_t to_read;
- size_t n1, n2;
- size_t tmp_read_ptr = rb->read_ptr;
-
- if ((free_cnt = ringbuf_read_space(rb)) == 0)
- return 0;
-
- to_read = cnt > free_cnt ? free_cnt : cnt;
- cnt2 = tmp_read_ptr + to_read;
-
- if (cnt2 > rb->size) {
- n1 = rb->size - tmp_read_ptr;
- n2 = cnt2 & rb->size_mask;
- } else {
- n1 = to_read;
- n2 = 0;
- }
-
- memcpy(dest, rb->buf + tmp_read_ptr, n1);
- advance_ptr(tmp_read_ptr, n1, rb->size_mask);
-
- if (n2) {
- memcpy((char*)dest + n1, rb->buf + tmp_read_ptr, n2);
- advance_ptr(tmp_read_ptr, n2, rb->size_mask);
- }
-
- return to_read;
-}
-
-/*
- * The copying data writer. Copy at most `cnt' bytes to `rb' from
- * `src'. Returns the actual number of bytes copied.
- */
-size_t ringbuf_write(struct ringbuf * rb, const void *src, size_t cnt)
-{
- size_t free_cnt;
- size_t cnt2;
- size_t to_write;
- size_t n1, n2;
-
- if ((free_cnt = ringbuf_write_space(rb)) == 0)
- return 0;
-
- to_write = cnt > free_cnt ? free_cnt : cnt;
- cnt2 = rb->write_ptr + to_write;
-
- if (cnt2 > rb->size) {
- n1 = rb->size - rb->write_ptr;
- n2 = cnt2 & rb->size_mask;
- } else {
- n1 = to_write;
- n2 = 0;
- }
-
- memcpy(rb->buf + rb->write_ptr, src, n1);
- ringbuf_write_advance(rb, n1);
-
- if (n2) {
- memcpy(rb->buf + rb->write_ptr, (const char*)src + n1, n2);
- ringbuf_write_advance(rb, n2);
- }
-
- return to_write;
-}
-
-/* Advance the read pointer `cnt' places. */
-void ringbuf_read_advance(struct ringbuf * rb, size_t cnt)
-{
- advance_ptr(rb->read_ptr, cnt, rb->size_mask);
-}
-
-/* Advance the write pointer `cnt' places. */
-void ringbuf_write_advance(struct ringbuf * rb, size_t cnt)
-{
- advance_ptr(rb->write_ptr, cnt, rb->size_mask);
-}
-
-/*
- * The non-copying data reader. `vec' is an array of two places. Set
- * the values at `vec' to hold the current readable data at `rb'. If
- * the readable data is in one segment the second segment has zero
- * length.
- */
-size_t ringbuf_get_read_vector(const struct ringbuf * rb, struct iovec * vec)
-{
- size_t free_cnt;
- size_t cnt2;
- size_t w = rb->write_ptr;
- size_t r = rb->read_ptr;
-
- if (w > r)
- free_cnt = w - r;
- else
- free_cnt = (w - r + rb->size) & rb->size_mask;
-
- cnt2 = r + free_cnt;
-
- if (cnt2 > rb->size) {
- /*
- * Two part vector: the rest of the buffer after the current
- * write ptr, plus some from the start of the buffer.
- */
- vec[0].iov_base = rb->buf + r;
- vec[0].iov_len = rb->size - r;
- vec[1].iov_base = rb->buf;
- vec[1].iov_len = cnt2 & rb->size_mask;
- } else {
- /* Single part vector: just the rest of the buffer */
- vec[0].iov_base = rb->buf + r;
- vec[0].iov_len = free_cnt;
- vec[1].iov_len = 0;
- }
- return vec[0].iov_len + vec[1].iov_len;
-}
-
-/*
- * The non-copying data writer. `vec' is an array of two places. Set
- * the values at `vec' to hold the current writeable data at `rb'. If
- * the writeable data is in one segment the second segment has zero
- * length.
- */
-size_t ringbuf_get_write_vector(const struct ringbuf * rb, struct iovec * vec)
-{
- size_t free_cnt;
- size_t cnt2;
- size_t w = rb->write_ptr;
- size_t r = rb->read_ptr;
-
- if (w > r)
- free_cnt = ((r - w + rb->size) & rb->size_mask) - 1;
- else if (w < r)
- free_cnt = (r - w) - 1;
- else
- free_cnt = rb->size - 1;
-
- cnt2 = w + free_cnt;
-
- if (cnt2 > rb->size) {
- /*
- * Two part vector: the rest of the buffer after the current
- * write ptr, plus some from the start of the buffer.
- */
- vec[0].iov_base = rb->buf + w;
- vec[0].iov_len = rb->size - w;
- vec[1].iov_base = rb->buf;
- vec[1].iov_len = cnt2 & rb->size_mask;
- } else {
- vec[0].iov_base = rb->buf + w;
- vec[0].iov_len = free_cnt;
- vec[1].iov_len = 0;
- }
- return vec[0].iov_len + vec[1].iov_len;
-}
-