osmo-msc/include/openbsc/msgb.h

75 lines
1.9 KiB
C

#ifndef _MSGB_H
#define _MSGB_H
/* (C) 2008 by Harald Welte <laforge@gnumonks.org>
* All Rights Reserved
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License as published by
* the Free Software Foundation; either version 2 of the License, or
* (at your option) any later version.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*
* You should have received a copy of the GNU General Public License along
* with this program; if not, write to the Free Software Foundation, Inc.,
* 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
*
*/
struct bts_link;
struct msgb {
/* ptr to the incoming (RX) or outgoing (TX) BTS link */
struct gsm_bts_link *bts_link;
u_int8_t l2_off;
u_int8_t l3_off;
u_int16_t data_len;
u_int16_t len;
unsigned char *head;
unsigned char *tail;
unsigned char *data;
unsigned char _data[0];
};
extern struct msgb *msgb_alloc(u_int16_t size);
extern void msgb_free(struct msgb *m);
#define msgb_l2(m) ((void *)(m->data + m->l2_off))
#define msgb_l3(m) ((void *)(m->data + m->l3_off))
static inline unsigned int msgb_headlen(const struct msgb *msgb)
{
return msgb->len - msgb->data_len;
}
static inline unsigned char *msgb_put(struct msgb *msgb, unsigned int len)
{
unsigned char *tmp = msgb->tail;
msgb->tail += len;
msgb->len += len;
return tmp;
}
static inline unsigned char *msgb_push(struct msgb *msgb, unsigned int len)
{
msgb->data -= len;
msgb->len += len;
return msgb->data;
}
static inline unsigned char *msgb_pull(struct msgb *msgb, unsigned int len)
{
msgb->len -= len;
return msgb->data += len;
}
static inline int msgb_tailroom(const struct msgb *msgb)
{
return (msgb->data + msgb->data_len) - msgb->tail;
}
#endif /* _MSGB_H */