fef
fb9ec2a8bc
This is required because the heap is shared among all tasks and protected using a mutex which only works in kernel space.
71 lines
1.5 KiB
C
71 lines
1.5 KiB
C
/* See the end of this file for copyright, license, and warranty information. */
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/* Simple ring buffer implementation. */
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#include <ardix/malloc.h>
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#include <ardix/ringbuf.h>
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#include <ardix/types.h>
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#include <stddef.h>
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struct ringbuf *ringbuf_create(size_t size)
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{
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struct ringbuf *buf = kmalloc(sizeof(*buf) + size);
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if (buf == NULL)
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return NULL;
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buf->capacity = size;
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buf->len = 0;
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buf->rpos = 0;
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buf->wpos = 0;
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return buf;
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}
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inline void ringbuf_destroy(struct ringbuf *buf)
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{
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kfree(buf);
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}
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size_t ringbuf_read(void *dest, struct ringbuf *buf, size_t len)
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{
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uint8_t *tmp = dest;
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while (len-- && buf->len) {
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*tmp++ = buf->data[buf->rpos++];
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buf->len--;
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/* wrap around if required */
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buf->rpos %= buf->capacity;
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}
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return (size_t)tmp - (size_t)dest;
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}
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size_t ringbuf_write(struct ringbuf *buf, const void *src, size_t len)
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{
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const uint8_t *tmp = src;
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while (len-- && buf->len != buf->capacity) {
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buf->data[buf->wpos++] = *tmp++;
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buf->len++;
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/* wrap around if required */
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buf->wpos %= buf->capacity;
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}
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return (size_t)tmp - (size_t)src;
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}
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/*
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* This file is part of Ardix.
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* Copyright (c) 2020, 2021 Felix Kopp <owo@fef.moe>.
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*
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* Ardix is non-violent software: you may only use, redistribute,
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* and/or modify it under the terms of the CNPLv6+ as found in
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* the LICENSE file in the source code root directory or at
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* <https://git.pixie.town/thufie/CNPL>.
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*
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* Ardix comes with ABSOLUTELY NO WARRANTY, to the extent
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* permitted by applicable law. See the CNPLv6+ for details.
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*/
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