mirror of
https://github.com/linux-msm/cdba.git
synced 2026-02-25 13:11:56 -08:00
7653f1afdb
Fixes clang warning:
circ_buf.c:49:9: warning: variable 'count' set but not used [-Wunused-but-set-variable]
size_t count = 0;
^
Signed-off-by: Krzysztof Kozlowski <krzysztof.kozlowski@linaro.org>
103 lines
2.8 KiB
C
103 lines
2.8 KiB
C
/*
|
|
* Copyright (c) 2018, Linaro Ltd.
|
|
* All rights reserved.
|
|
*
|
|
* Redistribution and use in source and binary forms, with or without
|
|
* modification, are permitted provided that the following conditions are met:
|
|
*
|
|
* 1. Redistributions of source code must retain the above copyright notice,
|
|
* this list of conditions and the following disclaimer.
|
|
*
|
|
* 2. Redistributions in binary form must reproduce the above copyright notice,
|
|
* this list of conditions and the following disclaimer in the documentation
|
|
* and/or other materials provided with the distribution.
|
|
*
|
|
* 3. Neither the name of the copyright holder nor the names of its contributors
|
|
* may be used to endorse or promote products derived from this software without
|
|
* specific prior written permission.
|
|
*
|
|
* THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
|
|
* AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
|
|
* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
|
|
* ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE
|
|
* LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
|
|
* CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
|
|
* SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
|
|
* INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
|
|
* CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
|
|
* ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
|
|
* POSSIBILITY OF SUCH DAMAGE.
|
|
*/
|
|
|
|
#include <errno.h>
|
|
#include <stdio.h>
|
|
#include <stdlib.h>
|
|
#include <unistd.h>
|
|
|
|
#include "circ_buf.h"
|
|
|
|
/**
|
|
* circ_fill() - read data into circular buffer
|
|
* @fd: non-blocking file descriptor to read
|
|
* @circ: circ_buf object to write to
|
|
*
|
|
* Return: 0 if fifo is full or fd depleted, negative errno on failure
|
|
*/
|
|
ssize_t circ_fill(int fd, struct circ_buf *circ)
|
|
{
|
|
ssize_t space;
|
|
ssize_t n = 0;
|
|
|
|
do {
|
|
space = CIRC_SPACE_TO_END(circ);
|
|
if (!space) {
|
|
errno = EAGAIN;
|
|
return -1;
|
|
}
|
|
|
|
n = read(fd, circ->buf + circ->head, space);
|
|
if (n == 0) {
|
|
errno = EPIPE;
|
|
return -1;
|
|
} else if (n < 0)
|
|
return -1;
|
|
|
|
circ->head = (circ->head + n) & (CIRC_BUF_SIZE - 1);
|
|
} while (n != space);
|
|
|
|
return 0;
|
|
}
|
|
|
|
size_t circ_peak(struct circ_buf *circ, void *buf, size_t len)
|
|
{
|
|
size_t tail = circ->tail;
|
|
char *p = buf;
|
|
|
|
while (len--) {
|
|
if (tail == circ->head)
|
|
return 0;
|
|
|
|
*p++ = circ->buf[tail];
|
|
|
|
tail = (tail + 1) & (CIRC_BUF_SIZE - 1);
|
|
}
|
|
|
|
return p - (char *)buf;
|
|
}
|
|
|
|
size_t circ_read(struct circ_buf *circ, void *buf, size_t len)
|
|
{
|
|
char *p = buf;
|
|
|
|
while (len--) {
|
|
if (circ->tail == circ->head)
|
|
return 0;
|
|
|
|
*p++ = circ->buf[circ->tail];
|
|
|
|
circ->tail = (circ->tail + 1) & (CIRC_BUF_SIZE - 1);
|
|
}
|
|
|
|
return p - (char *)buf;
|
|
}
|