freebsd-dev/sys/geom/virstor/binstream.c
Pawel Jakub Dawidek f854db0bf5 Bring in the GEOM Virtualisation class, which allows to create huge GEOM
providers with limited physical storage and add physical storage as
needed.

Submitted by:	Ivan Voras
Sponsored by:	Google Summer of Code 2006
Approved by:	re (kensmith)
2007-09-23 07:34:23 +00:00

186 lines
4.3 KiB
C

/*-
* Copyright (c) 2005 Ivan Voras <ivoras@gmail.com>
* 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.
*
* THIS SOFTWARE IS PROVIDED BY THE AUTHORS 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 AUTHORS 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.
*/
// $Id: binstream.c,v 1.1 2006/07/05 10:47:54 ivoras Exp $
#include <sys/cdefs.h>
__FBSDID("$FreeBSD$");
#include <sys/endian.h>
#include <sys/param.h>
#include <geom/virstor/binstream.h>
/* "Open" a binary stream for reading */
void
bs_open(bin_stream_t * bs, void *data)
{
bs->data = (char *)data;
bs->pos = 0;
}
/* "Reset" position in binary stream to zero */
void
bs_reset(bin_stream_t * bs)
{
bs->pos = 0;
}
/* Write a zero-terminated string; return next position */
unsigned
bs_write_str(bin_stream_t * bs, char *data)
{
int len = 0;
do {
*(bs->data + bs->pos + len) = *data;
len++;
} while (*(data++) != '\0');
bs->pos += len;
return bs->pos;
}
/* Write an arbitrary buffer; return next position */
unsigned
bs_write_buf(bin_stream_t * bs, char *data, unsigned data_size)
{
unsigned i;
for (i = 0; i < data_size; i++)
*(bs->data + bs->pos + i) = *(data + i);
bs->pos += data_size;
return bs->pos;
}
/* Write a 8bit uint; return next position. */
unsigned
bs_write_u8(bin_stream_t * bs, uint8_t data)
{
*((uint8_t *) (bs->data + bs->pos)) = data;
return ++(bs->pos);
}
/* Write a 16bit uint; return next position. */
unsigned
bs_write_u16(bin_stream_t * bs, uint16_t data)
{
le16enc(bs->data + bs->pos, data);
return (bs->pos += 2);
}
/* Write a 32bit uint; return next position. */
unsigned
bs_write_u32(bin_stream_t * bs, uint32_t data)
{
le32enc(bs->data + bs->pos, data);
return (bs->pos += 4);
}
/* Write a 64bit uint; return next position. */
unsigned
bs_write_u64(bin_stream_t * bs, uint64_t data)
{
le64enc(bs->data + bs->pos, data);
return (bs->pos += 8);
}
/* Read a 8bit uint & return it */
uint8_t
bs_read_u8(bin_stream_t * bs)
{
uint8_t data = *((uint8_t *) (bs->data + bs->pos));
bs->pos++;
return data;
}
/*
* Read a null-terminated string from stream into a buffer; buf_size is size
* of the buffer, including the final \0. Returns buf pointer or NULL if
* garbage input.
*/
char*
bs_read_str(bin_stream_t * bs, char *buf, unsigned buf_size)
{
unsigned len = 0;
char *work_buf = buf;
if (buf == NULL || buf_size < 1)
return NULL;
do {
*work_buf = *(bs->data + bs->pos + len);
} while (len++ < buf_size - 1 && *(work_buf++) != '\0');
*(buf + buf_size - 1) = '\0';
bs->pos += len;
return buf;
}
/* Read an arbitrary buffer. */
void
bs_read_buf(bin_stream_t * bs, char *buf, unsigned buf_size)
{
unsigned i;
for (i = 0; i < buf_size; i++)
*(buf + i) = *(bs->data + bs->pos + i);
bs->pos += buf_size;
}
/* Read a 16bit uint & return it */
uint16_t
bs_read_u16(bin_stream_t * bs)
{
uint16_t data = le16dec(bs->data + bs->pos);
bs->pos += 2;
return data;
}
/* Read a 32bit uint & return it */
uint32_t
bs_read_u32(bin_stream_t * bs)
{
uint32_t data = le32dec(bs->data + bs->pos);
bs->pos += 4;
return data;
}
/* Read a 64bit uint & return it */
uint64_t
bs_read_u64(bin_stream_t * bs)
{
uint64_t data = le64dec(bs->data + bs->pos);
bs->pos += 8;
return data;
}