buffer.c revision e74100e3f43887f048643973a1f4351daa3a9628
/*
* Copyright (C) 1998-2001 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.
*/
/* $Id: buffer.c,v 1.38 2002/01/05 07:28:39 bwelling Exp $ */
#include <config.h>
#include <isc/buffer.h>
#include <isc/mem.h>
#include <isc/region.h>
#include <isc/string.h>
#include <isc/util.h>
void
isc__buffer_init(isc_buffer_t *b, const void *base, unsigned int length) {
/*
* Make 'b' refer to the 'length'-byte region starting at 'base'.
* XXXDCL see the comment in buffer.h about base being const.
*/
REQUIRE(b != NULL);
ISC__BUFFER_INIT(b, base, length);
}
void
isc__buffer_invalidate(isc_buffer_t *b) {
/*
* Make 'b' an invalid buffer.
*/
REQUIRE(ISC_BUFFER_VALID(b));
REQUIRE(!ISC_LINK_LINKED(b, link));
REQUIRE(b->mctx == NULL);
ISC__BUFFER_INVALIDATE(b);
}
void
isc__buffer_region(isc_buffer_t *b, isc_region_t *r) {
/*
* Make 'r' refer to the region of 'b'.
*/
REQUIRE(ISC_BUFFER_VALID(b));
REQUIRE(r != NULL);
ISC__BUFFER_REGION(b, r);
}
void
isc__buffer_usedregion(isc_buffer_t *b, isc_region_t *r) {
/*
* Make 'r' refer to the used region of 'b'.
*/
REQUIRE(ISC_BUFFER_VALID(b));
REQUIRE(r != NULL);
ISC__BUFFER_USEDREGION(b, r);
}
void
isc__buffer_availableregion(isc_buffer_t *b, isc_region_t *r) {
/*
* Make 'r' refer to the available region of 'b'.
*/
REQUIRE(ISC_BUFFER_VALID(b));
REQUIRE(r != NULL);
ISC__BUFFER_AVAILABLEREGION(b, r);
}
void
isc__buffer_add(isc_buffer_t *b, unsigned int n) {
/*
* Increase the 'used' region of 'b' by 'n' bytes.
*/
REQUIRE(ISC_BUFFER_VALID(b));
REQUIRE(b->used + n <= b->length);
ISC__BUFFER_ADD(b, n);
}
void
isc__buffer_subtract(isc_buffer_t *b, unsigned int n) {
/*
* Decrease the 'used' region of 'b' by 'n' bytes.
*/
REQUIRE(ISC_BUFFER_VALID(b));
REQUIRE(b->used >= n);
ISC__BUFFER_SUBTRACT(b, n);
}
void
isc__buffer_clear(isc_buffer_t *b) {
/*
* Make the used region empty.
*/
REQUIRE(ISC_BUFFER_VALID(b));
ISC__BUFFER_CLEAR(b);
}
void
isc__buffer_consumedregion(isc_buffer_t *b, isc_region_t *r) {
/*
* Make 'r' refer to the consumed region of 'b'.
*/
REQUIRE(ISC_BUFFER_VALID(b));
REQUIRE(r != NULL);
ISC__BUFFER_CONSUMEDREGION(b, r);
}
void
isc__buffer_remainingregion(isc_buffer_t *b, isc_region_t *r) {
/*
* Make 'r' refer to the remaining region of 'b'.
*/
REQUIRE(ISC_BUFFER_VALID(b));
REQUIRE(r != NULL);
ISC__BUFFER_REMAININGREGION(b, r);
}
void
isc__buffer_activeregion(isc_buffer_t *b, isc_region_t *r) {
/*
* Make 'r' refer to the active region of 'b'.
*/
REQUIRE(ISC_BUFFER_VALID(b));
REQUIRE(r != NULL);
ISC__BUFFER_ACTIVEREGION(b, r);
}
void
isc__buffer_setactive(isc_buffer_t *b, unsigned int n) {
/*
* Sets the end of the active region 'n' bytes after current.
*/
REQUIRE(ISC_BUFFER_VALID(b));
REQUIRE(b->current + n <= b->used);
ISC__BUFFER_SETACTIVE(b, n);
}
void
isc__buffer_first(isc_buffer_t *b) {
/*
* Make the consumed region empty.
*/
REQUIRE(ISC_BUFFER_VALID(b));
ISC__BUFFER_FIRST(b);
}
void
isc__buffer_forward(isc_buffer_t *b, unsigned int n) {
/*
* Increase the 'consumed' region of 'b' by 'n' bytes.
*/
REQUIRE(ISC_BUFFER_VALID(b));
REQUIRE(b->current + n <= b->used);
ISC__BUFFER_FORWARD(b, n);
}
void
isc__buffer_back(isc_buffer_t *b, unsigned int n) {
/*
* Decrease the 'consumed' region of 'b' by 'n' bytes.
*/
REQUIRE(ISC_BUFFER_VALID(b));
REQUIRE(n <= b->current);
ISC__BUFFER_BACK(b, n);
}
void
isc_buffer_compact(isc_buffer_t *b) {
unsigned int length;
void *src;
/*
* Compact the used region by moving the remaining region so it occurs
* at the start of the buffer. The used region is shrunk by the size
* of the consumed region, and the consumed region is then made empty.
*/
REQUIRE(ISC_BUFFER_VALID(b));
src = isc_buffer_current(b);
length = isc_buffer_remaininglength(b);
(void)memmove(b->base, src, (size_t)length);
if (b->active > b->current)
b->active -= b->current;
else
b->active = 0;
b->current = 0;
b->used = length;
}
isc_uint8_t
isc_buffer_getuint8(isc_buffer_t *b) {
unsigned char *cp;
isc_uint8_t result;
/*
* Read an unsigned 8-bit integer from 'b' and return it.
*/
REQUIRE(ISC_BUFFER_VALID(b));
REQUIRE(b->used - b->current >= 1);
cp = isc_buffer_current(b);
b->current += 1;
result = ((isc_uint8_t)(cp[0]));
return (result);
}
void
isc__buffer_putuint8(isc_buffer_t *b, isc_uint8_t val) {
REQUIRE(ISC_BUFFER_VALID(b));
REQUIRE(b->used + 1 <= b->length);
ISC__BUFFER_PUTUINT8(b, val);
}
isc_uint16_t
isc_buffer_getuint16(isc_buffer_t *b) {
unsigned char *cp;
isc_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(ISC_BUFFER_VALID(b));
REQUIRE(b->used - b->current >= 2);
cp = isc_buffer_current(b);
b->current += 2;
result = ((unsigned int)(cp[0])) << 8;
result |= ((unsigned int)(cp[1]));
return (result);
}
void
isc__buffer_putuint16(isc_buffer_t *b, isc_uint16_t val) {
REQUIRE(ISC_BUFFER_VALID(b));
REQUIRE(b->used + 2 <= b->length);
ISC__BUFFER_PUTUINT16(b, val);
}
isc_uint32_t
isc_buffer_getuint32(isc_buffer_t *b) {
unsigned char *cp;
isc_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(ISC_BUFFER_VALID(b));
REQUIRE(b->used - b->current >= 4);
cp = isc_buffer_current(b);
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
isc__buffer_putuint32(isc_buffer_t *b, isc_uint32_t val) {
REQUIRE(ISC_BUFFER_VALID(b));
REQUIRE(b->used + 4 <= b->length);
ISC__BUFFER_PUTUINT32(b, val);
}
void
isc__buffer_putmem(isc_buffer_t *b, const unsigned char *base,
unsigned int length)
{
REQUIRE(ISC_BUFFER_VALID(b));
REQUIRE(b->used + length <= b->length);
ISC__BUFFER_PUTMEM(b, base, length);
}
void
isc__buffer_putstr(isc_buffer_t *b, const char *source) {
unsigned int l;
unsigned char *cp;
REQUIRE(ISC_BUFFER_VALID(b));
REQUIRE(source != NULL);
/*
* Do not use ISC__BUFFER_PUTSTR(), so strlen is only done once.
*/
l = strlen(source);
REQUIRE(l <= isc_buffer_availablelength(b));
cp = isc_buffer_used(b);
memcpy(cp, source, l);
b->used += l;
}
isc_result_t
isc_buffer_copyregion(isc_buffer_t *b, const isc_region_t *r) {
unsigned char *base;
unsigned int available;
REQUIRE(ISC_BUFFER_VALID(b));
REQUIRE(r != NULL);
/*
* XXXDCL
*/
base = isc_buffer_used(b);
available = isc_buffer_availablelength(b);
if (r->length > available)
return (ISC_R_NOSPACE);
memcpy(base, r->base, r->length);
b->used += r->length;
return (ISC_R_SUCCESS);
}
isc_result_t
isc_buffer_allocate(isc_mem_t *mctx, isc_buffer_t **dynbuffer,
unsigned int length)
{
isc_buffer_t *dbuf;
REQUIRE(dynbuffer != NULL);
REQUIRE(*dynbuffer == NULL);
dbuf = isc_mem_get(mctx, length + sizeof(isc_buffer_t));
if (dbuf == NULL)
return (ISC_R_NOMEMORY);
isc_buffer_init(dbuf, ((unsigned char *)dbuf) + sizeof(isc_buffer_t),
length);
dbuf->mctx = mctx;
*dynbuffer = dbuf;
return (ISC_R_SUCCESS);
}
void
isc_buffer_free(isc_buffer_t **dynbuffer) {
unsigned int real_length;
isc_buffer_t *dbuf;
isc_mem_t *mctx;
REQUIRE(dynbuffer != NULL);
REQUIRE(ISC_BUFFER_VALID(*dynbuffer));
REQUIRE((*dynbuffer)->mctx != NULL);
dbuf = *dynbuffer;
*dynbuffer = NULL; /* destroy external reference */
real_length = dbuf->length + sizeof(isc_buffer_t);
mctx = dbuf->mctx;
dbuf->mctx = NULL;
isc_buffer_invalidate(dbuf);
isc_mem_put(mctx, dbuf, real_length);
}