lwbuffer.c revision 915723e4007e177b10c0e1c9d1bfe77ac2bfe853
/*
* Copyright (C) 2000 Internet Software Consortium.
*
* Permission to use, copy, modify, and distribute this software for any
* purpose with or without fee is hereby granted, provided that the above
* copyright notice and this permission notice appear in all copies.
*
* THE SOFTWARE IS PROVIDED "AS IS" AND INTERNET SOFTWARE CONSORTIUM DISCLAIMS
* ALL WARRANTIES WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES
* OF MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL INTERNET SOFTWARE
* CONSORTIUM BE LIABLE FOR ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL
* DAMAGES OR ANY DAMAGES WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR
* PROFITS, WHETHER IN AN ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS
* ACTION, ARISING OUT OF OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS
* SOFTWARE.
*/
/* XXXMLG */
#define REQUIRE(x)
#include <config.h>
#include <string.h>
#include <lwres/lwbuffer.h>
void
lwres_buffer_init(lwres_buffer_t *b, void *base, unsigned int length)
{
/*
* Make 'b' refer to the 'length'-byte region starting at base.
*/
REQUIRE(b != NULL);
b->magic = LWRES_BUFFER_MAGIC;
b->base = base;
b->length = length;
b->used = 0;
b->current = 0;
b->active = 0;
}
void
lwres_buffer_invalidate(lwres_buffer_t *b)
{
/*
* Make 'b' an invalid buffer.
*/
REQUIRE(LWRES_BUFFER_VALID(b));
b->magic = 0;
b->base = NULL;
b->length = 0;
b->used = 0;
b->current = 0;
b->active = 0;
}
void
lwres_buffer_add(lwres_buffer_t *b, unsigned int n)
{
/*
* Increase the 'used' region of 'b' by 'n' bytes.
*/
REQUIRE(LWRES_BUFFER_VALID(b));
REQUIRE(b->used + n <= b->length);
b->used += n;
}
void
lwres_buffer_subtract(lwres_buffer_t *b, unsigned int n)
{
/*
* Decrease the 'used' region of 'b' by 'n' bytes.
*/
REQUIRE(LWRES_BUFFER_VALID(b));
REQUIRE(b->used >= n);
b->used -= n;
if (b->current > b->used)
b->current = b->used;
if (b->active > b->used)
b->active = b->used;
}
void
lwres_buffer_clear(lwres_buffer_t *b)
{
/*
* Make the used region empty.
*/
REQUIRE(LWRES_BUFFER_VALID(b));
b->used = 0;
b->current = 0;
b->active = 0;
}
void
lwres_buffer_first(lwres_buffer_t *b)
{
/*
* Make the consumed region empty.
*/
REQUIRE(LWRES_BUFFER_VALID(b));
b->current = 0;
}
void
lwres_buffer_forward(lwres_buffer_t *b, unsigned int n)
{
/*
* Increase the 'consumed' region of 'b' by 'n' bytes.
*/
REQUIRE(LWRES_BUFFER_VALID(b));
REQUIRE(b->current + n <= b->used);
b->current += n;
}
void
lwres_buffer_back(lwres_buffer_t *b, unsigned int n)
{
/*
* Decrease the 'consumed' region of 'b' by 'n' bytes.
*/
REQUIRE(LWRES_BUFFER_VALID(b));
REQUIRE(n <= b->current);
b->current -= n;
}
lwres_uint8_t
lwres_buffer_getuint8(lwres_buffer_t *b)
{
unsigned char *cp;
lwres_uint8_t result;
/*
* Read an unsigned 8-bit integer from 'b' and return it.
*/
REQUIRE(LWRES_BUFFER_VALID(b));
REQUIRE(b->used - b->current >= 1);
cp = b->base;
cp += b->current;
b->current += 1;
result = ((unsigned int)(cp[0]));
return (result);
}
void
lwres_buffer_putuint8(lwres_buffer_t *b, lwres_uint8_t val)
{
unsigned char *cp;
REQUIRE(LWRES_BUFFER_VALID(b));
REQUIRE(b->used + 1 <= b->length);
cp = b->base;
cp += b->used;
b->used += 1;
cp[0] = (val & 0x00ff);
}
lwres_uint16_t
lwres_buffer_getuint16(lwres_buffer_t *b)
{
unsigned char *cp;
lwres_uint16_t result;
/*
* Read an unsigned 16-bit integer in network byte order from 'b',
* convert it to host byte order, and return it.
*/
REQUIRE(LWRES_BUFFER_VALID(b));
REQUIRE(b->used - b->current >= 2);
cp = b->base;
cp += b->current;
b->current += 2;
result = ((unsigned int)(cp[0])) << 8;
result |= ((unsigned int)(cp[1]));
return (result);
}
void
lwres_buffer_putuint16(lwres_buffer_t *b, lwres_uint16_t val)
{
unsigned char *cp;
REQUIRE(LWRES_BUFFER_VALID(b));
REQUIRE(b->used + 2 <= b->length);
cp = b->base;
cp += b->used;
b->used += 2;
cp[0] = (val & 0xff00) >> 8;
cp[1] = (val & 0x00ff);
}
lwres_uint32_t
lwres_buffer_getuint32(lwres_buffer_t *b)
{
unsigned char *cp;
lwres_uint32_t result;
/*
* Read an unsigned 32-bit integer in network byte order from 'b',
* convert it to host byte order, and return it.
*/
REQUIRE(LWRES_BUFFER_VALID(b));
REQUIRE(b->used - b->current >= 4);
cp = b->base;
cp += b->current;
b->current += 4;
result = ((unsigned int)(cp[0])) << 24;
result |= ((unsigned int)(cp[1])) << 16;
result |= ((unsigned int)(cp[2])) << 8;
result |= ((unsigned int)(cp[3]));
return (result);
}
void
lwres_buffer_putuint32(lwres_buffer_t *b, lwres_uint32_t val)
{
unsigned char *cp;
REQUIRE(LWRES_BUFFER_VALID(b));
REQUIRE(b->used + 4 <= b->length);
cp = b->base;
cp += b->used;
b->used += 4;
cp[0] = (unsigned char)((val & 0xff000000) >> 24);
cp[1] = (unsigned char)((val & 0x00ff0000) >> 16);
cp[2] = (unsigned char)((val & 0x0000ff00) >> 8);
cp[3] = (unsigned char)(val & 0x000000ff);
}
void
lwres_buffer_putmem(lwres_buffer_t *b, const unsigned char *base,
unsigned int length)
{
unsigned char *cp;
REQUIRE(LWRES_BUFFER_VALID(b));
REQUIRE(b->used + length <= b->length);
cp = (unsigned char *)b->base + b->used;
memcpy(cp, base, length);
b->used += length;
}
void
lwres_buffer_getmem(lwres_buffer_t *b, unsigned char *base,
unsigned int length)
{
unsigned char *cp;
REQUIRE(LWRES_BUFFER_VALID(b));
REQUIRE(b->used - b->current >= length);
cp = b->base;
cp += b->current;
b->current += length;
memcpy(base, cp, length);
}