freebsd-dev/sys/netatm/uni/unisig_mbuf.c
Poul-Henning Kamp 1820df7a2d Add new files for HARP3
Host ATM Research Platform (HARP), Network Computing Services, Inc.
This software was developed with the support of the Defense Advanced
Research Projects Agency (DARPA).
1998-09-15 08:23:17 +00:00

486 lines
8.3 KiB
C

/*
*
* ===================================
* HARP | Host ATM Research Platform
* ===================================
*
*
* This Host ATM Research Platform ("HARP") file (the "Software") is
* made available by Network Computing Services, Inc. ("NetworkCS")
* "AS IS". NetworkCS does not provide maintenance, improvements or
* support of any kind.
*
* NETWORKCS MAKES NO WARRANTIES OR REPRESENTATIONS, EXPRESS OR IMPLIED,
* INCLUDING, BUT NOT LIMITED TO, IMPLIED WARRANTIES OF MERCHANTABILITY
* AND FITNESS FOR A PARTICULAR PURPOSE, AS TO ANY ELEMENT OF THE
* SOFTWARE OR ANY SUPPORT PROVIDED IN CONNECTION WITH THIS SOFTWARE.
* In no event shall NetworkCS be responsible for any damages, including
* but not limited to consequential damages, arising from or relating to
* any use of the Software or related support.
*
* Copyright 1994-1998 Network Computing Services, Inc.
*
* Copies of this Software may be made, however, the above copyright
* notice must be reproduced on all copies.
*
* @(#) $Id: unisig_mbuf.c,v 1.6 1998/08/26 23:29:22 mks Exp $
*
*/
/*
* ATM Forum UNI 3.0/3.1 Signalling Manager
* ----------------------------------------
*
* Message buffer handling routines
*
*/
#ifndef lint
static char *RCSid = "@(#) $Id: unisig_mbuf.c,v 1.6 1998/08/26 23:29:22 mks Exp $";
#endif
#include <netatm/kern_include.h>
#include <netatm/uni/unisig_var.h>
#include <netatm/uni/unisig_mbuf.h>
#include <netatm/uni/unisig_msg.h>
/*
* Initialize a unisig formatting structure
*
* Arguments:
* usf pointer to a unisig formatting structure
* usp pointer to a unisig protocol instance
* buf pointer to a buffer chain (decode only)
* op operation code (encode or decode)
* headroom headroom to leave in first buffer
*
* Returns:
* 0 success
* errno error encountered
*
*/
int
usf_init(usf, usp, buf, op, headroom)
struct usfmt *usf;
struct unisig *usp;
KBuffer *buf;
int op;
int headroom;
{
KBuffer *m;
ATM_DEBUG3("usf_init: usf=0x%x, buf=0x%x, op=%d\n",
(int) usf, (int) buf, op);
/*
* Check parameters
*/
if (!usf)
return(EINVAL);
switch(op) {
case USF_ENCODE:
/*
* Get a buffer
*/
KB_ALLOCPKT(m, USF_MIN_ALLOC, KB_F_NOWAIT, KB_T_DATA);
if (m == NULL)
return(ENOMEM);
KB_LEN(m) = 0;
if (headroom < KB_BFRLEN(m)) {
KB_HEADSET(m, headroom);
}
break;
case USF_DECODE:
/*
* Verify buffer address
*/
if (!buf)
return(EINVAL);
m = buf;
break;
default:
return(EINVAL);
}
/*
* Save parameters in formatting structure
*/
usf->usf_m_addr = m;
usf->usf_m_base = m;
usf->usf_loc = 0;
usf->usf_op = op;
usf->usf_sig = usp;
return(0);
}
/*
* Get or put the next byte of a signalling message
*
* Arguments:
* usf pointer to a unisig formatting structure
* c pointer to the byte to send from or receive into
*
* Returns:
* 0 success
* errno error encountered
*
*/
int
usf_byte(usf, c)
struct usfmt *usf;
u_char *c;
{
u_char *mp;
KBuffer *m = usf->usf_m_addr, *m1;
int space;
switch (usf->usf_op) {
case USF_DECODE:
/*
* Make sure we're not past the end of the buffer
* (allowing for zero-length buffers)
*/
while (usf->usf_loc >= KB_LEN(m)) {
if (KB_NEXT(usf->usf_m_addr)) {
usf->usf_m_addr = m = KB_NEXT(usf->usf_m_addr);
usf->usf_loc = 0;
} else {
return(EMSGSIZE);
}
}
/*
* Get the data from the buffer
*/
KB_DATASTART(m, mp, u_char *);
*c = mp[usf->usf_loc];
usf->usf_loc++;
break;
case USF_ENCODE:
/*
* If the current buffer is full, get another
*/
KB_TAILROOM(m, space);
if (space == 0) {
KB_ALLOC(m1, USF_MIN_ALLOC, KB_F_NOWAIT, KB_T_DATA);
if (m1 == NULL)
return(ENOMEM);
KB_LEN(m1) = 0;
KB_LINK(m1, m);
usf->usf_m_addr = m = m1;
usf->usf_loc = 0;
}
/*
* Put the data into the buffer
*/
KB_DATASTART(m, mp, u_char *);
mp[usf->usf_loc] = *c;
KB_TAILADJ(m, 1);
usf->usf_loc++;
break;
default:
/*
* Invalid operation code
*/
return(EINVAL);
}
return(0);
}
/*
* Get or put a short integer
*
* Arguments:
* usf pointer to a unisig formatting structure
* s pointer to a short to send from or receive into
*
* Returns:
* 0 success
* errno error encountered
*
*/
int
usf_short(usf, s)
struct usfmt *usf;
u_short *s;
{
int rc;
union {
u_short value;
u_char b[sizeof(u_short)];
} tval;
tval.value = 0;
if (usf->usf_op == USF_ENCODE)
tval.value = htons(*s);
if (rc = usf_byte(usf, &tval.b[0]))
return(rc);
if (rc = usf_byte(usf, &tval.b[1]))
return(rc);
if (usf->usf_op == USF_DECODE)
*s = ntohs(tval.value);
return(0);
}
/*
* Get or put a 3-byte integer
*
* Arguments:
* usf pointer to a unisig formatting structure
* i pointer to an integer to send from or receive into
*
* Returns:
* 0 success
* errno error encountered
*
*/
int
usf_int3(usf, i)
struct usfmt *usf;
u_int *i;
{
int j, rc;
union {
u_int value;
u_char b[sizeof(u_int)];
} tval;
tval.value = 0;
if (usf->usf_op == USF_ENCODE)
tval.value = htonl(*i);
for (j=0; j<3; j++) {
rc = usf_byte(usf, &tval.b[j+sizeof(u_int)-3]);
if (rc)
return(rc);
}
if (usf->usf_op == USF_DECODE)
*i = ntohl(tval.value);
return(rc);
}
/*
* Get or put an integer
*
* Arguments:
* usf pointer to a unisig formatting structure
* i pointer to an integer to send from or receive into
*
* Returns:
* 0 success
* errno error encountered
*
*/
int
usf_int(usf, i)
struct usfmt *usf;
u_int *i;
{
int j, rc;
union {
u_int value;
u_char b[sizeof(u_int)];
} tval;
if (usf->usf_op == USF_ENCODE)
tval.value = htonl(*i);
for (j=0; j<4; j++) {
rc = usf_byte(usf, &tval.b[j+sizeof(u_int)-4]);
if (rc)
return(rc);
}
if (usf->usf_op == USF_DECODE)
*i = ntohl(tval.value);
return(rc);
}
/*
* Get or put an extented field
*
* An extented field consists of a string of bytes. All but the last
* byte of the field has the high-order bit set to zero. When decoding,
* this routine will read bytes until either the input is exhausted or
* a byte with a high-order one is found. Whe encoding, it will take an
* unsigned integer and write until the highest-order one bit has been
* written.
*
* Arguments:
* usf pointer to a unisig formatting structure
* i pointer to an integer to send from or receive into
*
* Returns:
* 0 success
* errno error encountered
*
*/
int
usf_ext(usf, i)
struct usfmt *usf;
u_int *i;
{
int j, rc;
u_char c, buff[sizeof(u_int)+1];
u_int val;
union {
u_int value;
u_char b[sizeof(u_int)];
} tval;
switch(usf->usf_op) {
case USF_ENCODE:
val = *i;
j = 0;
while (val) {
tval.value = htonl(val);
buff[j] = tval.b[sizeof(u_int)-1] & UNI_IE_EXT_MASK;
val >>= 7;
j++;
}
j--;
buff[0] |= UNI_IE_EXT_BIT;
for (; j>=0; j--) {
rc = usf_byte(usf, &buff[j]);
if (rc)
return(rc);
}
break;
case USF_DECODE:
c = 0;
val = 0;
while (!(c & UNI_IE_EXT_BIT)) {
rc = usf_byte(usf, &c);
if (rc)
return(rc);
val = (val << 7) + (c & UNI_IE_EXT_MASK);
}
*i = val;
break;
default:
return(EINVAL);
}
return(0);
}
/*
* Count the bytes remaining to be decoded
*
* Arguments:
* usf pointer to a unisig formatting structure
*
* Returns:
* int the number of bytes in the buffer chain remaining to
* be decoded
*
*/
int
usf_count(usf)
struct usfmt *usf;
{
int count;
KBuffer *m = usf->usf_m_addr;
/*
* Return zero if we're not decoding
*/
if (usf->usf_op != USF_DECODE)
return (0);
/*
* Calculate the length of data remaining in the current buffer
*/
count = KB_LEN(m) - usf->usf_loc;
/*
* Loop through any remaining buffers, adding in their lengths
*/
while (KB_NEXT(m)) {
m = KB_NEXT(m);
count += KB_LEN(m);
}
return(count);
}
/*
* Get or put the next byte of a signalling message and return
* the byte's buffer address
*
* Arguments:
* usf pointer to a unisig formatting structure
* c pointer to the byte to send from or receive into
* bp address to store the byte's buffer address
*
* Returns:
* 0 success
* errno error encountered
*
*/
int
usf_byte_mark(usf, c, bp)
struct usfmt *usf;
u_char *c;
u_char **bp;
{
u_char *mp;
int rc;
/*
* First, get/put the data byte
*/
rc = usf_byte(usf, c);
if (rc) {
/*
* Error encountered
*/
*bp = NULL;
return (rc);
}
/*
* Now return the buffer address of that byte
*/
KB_DATASTART(usf->usf_m_addr, mp, u_char *);
*bp = &mp[usf->usf_loc - 1];
return (0);
}