107 lines
3.1 KiB
C
107 lines
3.1 KiB
C
/* $NetBSD: buffer.h,v 1.3 2006/01/04 22:05:26 christos Exp $ */
|
|
|
|
/*-
|
|
* Copyright (c) 2005 The NetBSD Foundation, Inc.
|
|
* All rights reserved.
|
|
*
|
|
* This code is derived from software contributed to The NetBSD Foundation
|
|
* by Christos Zoulas.
|
|
*
|
|
* 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. All advertising materials mentioning features or use of this software
|
|
* must display the following acknowledgement:
|
|
* This product includes software developed by the NetBSD
|
|
* Foundation, Inc. and its contributors.
|
|
* 4. Neither the name of The NetBSD Foundation 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 NETBSD FOUNDATION, INC. 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 FOUNDATION 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 <stddef.h>
|
|
#include <stdio.h>
|
|
#include <stdlib.h>
|
|
#include <err.h>
|
|
|
|
#define BUF_SIZE BUFSIZ
|
|
struct buffer {
|
|
char *ptr;
|
|
char *bptr;
|
|
char *eptr;
|
|
};
|
|
|
|
static void
|
|
buf_init(struct buffer *buf)
|
|
{
|
|
buf->ptr = buf->bptr = malloc(BUF_SIZE);
|
|
if (buf->ptr == NULL)
|
|
err(1, "Cannot allocate buffer");
|
|
buf->eptr = buf->ptr + BUF_SIZE;
|
|
}
|
|
|
|
static void
|
|
buf_end(struct buffer *buf)
|
|
{
|
|
free(buf->bptr);
|
|
}
|
|
|
|
static void
|
|
buf_grow(struct buffer *buf, size_t minsize)
|
|
{
|
|
ptrdiff_t diff;
|
|
size_t len = (buf->eptr - buf->bptr) +
|
|
(minsize > BUF_SIZE ? minsize : BUF_SIZE);
|
|
char *nptr = realloc(buf->bptr, len);
|
|
|
|
if (nptr == NULL)
|
|
err(1, "Cannot grow buffer");
|
|
|
|
if (nptr == buf->bptr) {
|
|
buf->eptr = buf->bptr + len;
|
|
return;
|
|
}
|
|
|
|
diff = nptr - buf->bptr;
|
|
buf->bptr += diff;
|
|
buf->eptr = buf->bptr + len;
|
|
buf->ptr += diff;
|
|
}
|
|
|
|
static inline void
|
|
buf_putc(struct buffer *buf, char c)
|
|
{
|
|
if (buf->ptr >= buf->eptr)
|
|
buf_grow(buf, 1);
|
|
*buf->ptr++ = c;
|
|
}
|
|
|
|
static inline void
|
|
buf_reset(struct buffer *buf)
|
|
{
|
|
buf->ptr = buf->bptr;
|
|
}
|
|
|
|
static inline char
|
|
buf_unputc(struct buffer *buf)
|
|
{
|
|
return buf->ptr > buf->bptr ? *--buf->ptr : '\0';
|
|
}
|