libosmocore  0.9.0
Osmocom core library
msgb.h
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1 #pragma once
2 
3 /* (C) 2008 by Harald Welte <laforge@gnumonks.org>
4  * All Rights Reserved
5  *
6  * This program is free software; you can redistribute it and/or modify
7  * it under the terms of the GNU General Public License as published by
8  * the Free Software Foundation; either version 2 of the License, or
9  * (at your option) any later version.
10  *
11  * This program is distributed in the hope that it will be useful,
12  * but WITHOUT ANY WARRANTY; without even the implied warranty of
13  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
14  * GNU General Public License for more details.
15  *
16  * You should have received a copy of the GNU General Public License along
17  * with this program; if not, write to the Free Software Foundation, Inc.,
18  * 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
19  *
20  */
21 
22 #include <stdint.h>
23 #include <osmocom/core/linuxlist.h>
24 #include <osmocom/core/utils.h>
25 #include <osmocom/core/bits.h>
26 
39 #define MSGB_DEBUG
40 
42 struct msgb {
43  struct llist_head list;
46  /* Part of which TRX logical channel we were received / transmitted */
47  /* FIXME: move them into the control buffer */
48  union {
49  void *dst;
50  struct gsm_bts_trx *trx;
51  };
52  struct gsm_lchan *lchan;
54  unsigned char *l1h;
55  unsigned char *l2h;
56  unsigned char *l3h;
57  unsigned char *l4h;
59  unsigned long cb[5];
61  uint16_t data_len;
62  uint16_t len;
64  unsigned char *head;
65  unsigned char *tail;
66  unsigned char *data;
67  unsigned char _data[0];
68 };
69 
70 extern struct msgb *msgb_alloc(uint16_t size, const char *name);
71 extern void msgb_free(struct msgb *m);
72 extern void msgb_enqueue(struct llist_head *queue, struct msgb *msg);
73 extern struct msgb *msgb_dequeue(struct llist_head *queue);
74 extern void msgb_reset(struct msgb *m);
75 uint16_t msgb_length(const struct msgb *msg);
76 extern const char *msgb_hexdump(const struct msgb *msg);
77 
78 #ifdef MSGB_DEBUG
79 #include <osmocom/core/panic.h>
80 #define MSGB_ABORT(msg, fmt, args ...) do { \
81  osmo_panic("msgb(%p): " fmt, msg, ## args); \
82  } while(0)
83 #else
84 #define MSGB_ABORT(msg, fmt, args ...)
85 #endif
86 
88 #define msgb_l1(m) ((void *)(m->l1h))
89 
90 #define msgb_l2(m) ((void *)(m->l2h))
91 
92 #define msgb_l3(m) ((void *)(m->l3h))
93 
94 #define msgb_sms(m) ((void *)(m->l4h))
95 
103 static inline unsigned int msgb_l1len(const struct msgb *msgb)
104 {
105  return msgb->tail - (uint8_t *)msgb_l1(msgb);
106 }
107 
115 static inline unsigned int msgb_l2len(const struct msgb *msgb)
116 {
117  return msgb->tail - (uint8_t *)msgb_l2(msgb);
118 }
119 
127 static inline unsigned int msgb_l3len(const struct msgb *msgb)
128 {
129  return msgb->tail - (uint8_t *)msgb_l3(msgb);
130 }
131 
139 static inline unsigned int msgb_headlen(const struct msgb *msgb)
140 {
141  return msgb->len - msgb->data_len;
142 }
143 
151 static inline int msgb_tailroom(const struct msgb *msgb)
152 {
153  return (msgb->head + msgb->data_len) - msgb->tail;
154 }
155 
163 static inline int msgb_headroom(const struct msgb *msgb)
164 {
165  return (msgb->data - msgb->head);
166 }
167 
180 static inline unsigned char *msgb_put(struct msgb *msgb, unsigned int len)
181 {
182  unsigned char *tmp = msgb->tail;
183  if (msgb_tailroom(msgb) < (int) len)
184  MSGB_ABORT(msgb, "Not enough tailroom msgb_push (%u < %u)\n",
185  msgb_tailroom(msgb), len);
186  msgb->tail += len;
187  msgb->len += len;
188  return tmp;
189 }
190 
195 static inline void msgb_put_u8(struct msgb *msgb, uint8_t word)
196 {
197  uint8_t *space = msgb_put(msgb, 1);
198  space[0] = word & 0xFF;
199 }
200 
205 static inline void msgb_put_u16(struct msgb *msgb, uint16_t word)
206 {
207  uint8_t *space = msgb_put(msgb, 2);
208  osmo_store16be(word, space);
209 }
210 
215 static inline void msgb_put_u32(struct msgb *msgb, uint32_t word)
216 {
217  uint8_t *space = msgb_put(msgb, 4);
218  osmo_store32be(word, space);
219 }
220 
225 static inline unsigned char *msgb_get(struct msgb *msgb, unsigned int len)
226 {
227  unsigned char *tmp = msgb->tail - len;
228  if (msgb_length(msgb) < len)
229  MSGB_ABORT(msgb, "msgb too small to get %u (len %u)\n",
230  len, msgb_length(msgb));
231  msgb->tail -= len;
232  msgb->len -= len;
233  return tmp;
234 }
235 
240 static inline uint8_t msgb_get_u8(struct msgb *msgb)
241 {
242  uint8_t *space = msgb_get(msgb, 1);
243  return space[0];
244 }
245 
250 static inline uint16_t msgb_get_u16(struct msgb *msgb)
251 {
252  uint8_t *space = msgb_get(msgb, 2);
253  return osmo_load16be(space);
254 }
255 
260 static inline uint32_t msgb_get_u32(struct msgb *msgb)
261 {
262  uint8_t *space = msgb_get(msgb, 4);
263  return osmo_load32be(space);
264 }
265 
278 static inline unsigned char *msgb_push(struct msgb *msgb, unsigned int len)
279 {
280  if (msgb_headroom(msgb) < (int) len)
281  MSGB_ABORT(msgb, "Not enough headroom msgb_push (%u < %u)\n",
282  msgb_headroom(msgb), len);
283  msgb->data -= len;
284  msgb->len += len;
285  return msgb->data;
286 }
287 
297 static inline unsigned char *msgb_pull(struct msgb *msgb, unsigned int len)
298 {
299  msgb->len -= len;
300  return msgb->data += len;
301 }
302 
311 static inline unsigned char *msgb_pull_to_l3(struct msgb *msg)
312 {
313  unsigned char *ret = msgb_pull(msg, msg->l3h - msg->data);
314  msg->l1h = msg->l2h = NULL;
315  return ret;
316 }
317 
322 static inline uint8_t msgb_pull_u8(struct msgb *msgb)
323 {
324  uint8_t *space = msgb_pull(msgb, 1) - 1;
325  return space[0];
326 }
327 
332 static inline uint16_t msgb_pull_u16(struct msgb *msgb)
333 {
334  uint8_t *space = msgb_pull(msgb, 2) - 2;
335  return osmo_load16be(space);
336 }
337 
342 static inline uint32_t msgb_pull_u32(struct msgb *msgb)
343 {
344  uint8_t *space = msgb_pull(msgb, 4) - 4;
345  return osmo_load32be(space);
346 }
347 
359 static inline void msgb_reserve(struct msgb *msg, int len)
360 {
361  msg->data += len;
362  msg->tail += len;
363 }
364 
370 static inline int msgb_trim(struct msgb *msg, int len)
371 {
372  if (len > msg->data_len)
373  return -1;
374 
375  msg->len = len;
376  msg->tail = msg->data + len;
377 
378  return 0;
379 }
380 
386 static inline int msgb_l3trim(struct msgb *msg, int l3len)
387 {
388  return msgb_trim(msg, (msg->l3h - msg->data) + l3len);
389 }
390 
401 static inline struct msgb *msgb_alloc_headroom(int size, int headroom,
402  const char *name)
403 {
404  osmo_static_assert(size > headroom, headroom_bigger);
405 
406  struct msgb *msg = msgb_alloc(size, name);
407  if (msg)
408  msgb_reserve(msg, headroom);
409  return msg;
410 }
411 
412 /* non inline functions to ease binding */
413 
414 uint8_t *msgb_data(const struct msgb *msg);
415 void msgb_set_talloc_ctx(void *ctx);
416 
static unsigned char * msgb_put(struct msgb *msgb, unsigned int len)
append data to end of message buffer
Definition: msgb.h:180
static uint16_t msgb_pull_u16(struct msgb *msgb)
remove uint16 from front of message
Definition: msgb.h:332
static unsigned int msgb_l3len(const struct msgb *msgb)
determine length of L3 message
Definition: msgb.h:127
unsigned long cb[5]
control buffer
Definition: msgb.h:59
unsigned char * l3h
pointer to Layer 3 header. For OML: FOM; RSL: 04.08; GPRS: BSSGP
Definition: msgb.h:56
#define msgb_l3(m)
obtain L3 header of msgb
Definition: msgb.h:92
#define msgb_l1(m)
obtain L1 header of msgb
Definition: msgb.h:88
struct msgb * msgb_alloc(uint16_t size, const char *name)
Allocate a new message buffer.
Definition: msgb.c:47
unsigned char * data
start of message in buffer
Definition: msgb.h:66
Osmocom message buffer.
Definition: msgb.h:42
void msgb_set_talloc_ctx(void *ctx)
Set the talloc context for msgb_alloc.
Definition: msgb.c:151
static int msgb_l3trim(struct msgb *msg, int l3len)
Trim the msgb to a given layer3 length.
Definition: msgb.h:386
static int msgb_trim(struct msgb *msg, int len)
Trim the msgb to a given absolute length.
Definition: msgb.h:370
uint16_t len
length of bytes used in msgb
Definition: msgb.h:62
static unsigned char * msgb_pull_to_l3(struct msgb *msg)
remove (pull) all headers in front of l3h from the message buffer.
Definition: msgb.h:311
void msgb_free(struct msgb *m)
Release given message buffer.
Definition: msgb.c:70
static int msgb_tailroom(const struct msgb *msgb)
determine how much tail room is left in msgb
Definition: msgb.h:151
unsigned char * l4h
pointer to layer 4 header
Definition: msgb.h:57
static unsigned int msgb_l1len(const struct msgb *msgb)
determine length of L1 message
Definition: msgb.h:103
static unsigned char * msgb_get(struct msgb *msgb, unsigned int len)
remove data from end of message
Definition: msgb.h:225
const char * msgb_hexdump(const struct msgb *msg)
Return a (static) buffer containing a hexdump of the msg.
Definition: msgb.c:160
struct msgb * msgb_dequeue(struct llist_head *queue)
Dequeue message buffer from head of queue.
Definition: msgb.c:94
static uint32_t msgb_pull_u32(struct msgb *msgb)
remove uint32 from front of message
Definition: msgb.h:342
static unsigned int msgb_l2len(const struct msgb *msgb)
determine length of L2 message
Definition: msgb.h:115
static struct msgb * msgb_alloc_headroom(int size, int headroom, const char *name)
Allocate message buffer with specified headroom.
Definition: msgb.h:401
static unsigned char * msgb_push(struct msgb *msgb, unsigned int len)
prepend (push) some data to start of message
Definition: msgb.h:278
Definition: linuxlist.h:42
unsigned char * l1h
pointer to Layer1 header (if any)
Definition: msgb.h:54
static uint8_t msgb_pull_u8(struct msgb *msgb)
remove uint8 from front of message
Definition: msgb.h:322
void msgb_enqueue(struct llist_head *queue, struct msgb *msg)
Enqueue message buffer to tail of a queue.
Definition: msgb.c:82
struct gsm_lchan * lchan
logical channel
Definition: msgb.h:52
void msgb_reset(struct msgb *m)
Re-set all message buffer pointers.
Definition: msgb.c:114
static void msgb_reserve(struct msgb *msg, int len)
Increase headroom of empty msgb, reducing the tailroom.
Definition: msgb.h:359
unsigned char * tail
end of message in buffer
Definition: msgb.h:65
static void msgb_put_u16(struct msgb *msgb, uint16_t word)
append a uint16 value to the end of the message
Definition: msgb.h:205
static uint8_t msgb_get_u8(struct msgb *msgb)
remove uint8 from end of message
Definition: msgb.h:240
unsigned char * l2h
pointer to A-bis layer 2 header: OML, RSL(RLL), NS
Definition: msgb.h:55
unsigned char * head
start of underlying memory buffer
Definition: msgb.h:64
static uint32_t msgb_get_u32(struct msgb *msgb)
remove uint32 from end of message
Definition: msgb.h:260
static int msgb_headroom(const struct msgb *msgb)
determine the amount of headroom in msgb
Definition: msgb.h:163
Osmocom bit level support code.
uint16_t data_len
length of underlying data array
Definition: msgb.h:61
unsigned char _data[0]
optional immediate data array
Definition: msgb.h:67
struct llist_head list
linked list header
Definition: msgb.h:43
uint8_t * msgb_data(const struct msgb *msg)
get pointer to data section of message buffer
Definition: msgb.c:134
#define msgb_l2(m)
obtain L2 header of msgb
Definition: msgb.h:90
static uint16_t msgb_get_u16(struct msgb *msgb)
remove uint16 from end of message
Definition: msgb.h:250
void * dst
reference of origin/destination
Definition: msgb.h:49
static unsigned int msgb_headlen(const struct msgb *msgb)
determine the length of the header
Definition: msgb.h:139
uint16_t msgb_length(const struct msgb *msg)
get length of message buffer
Definition: msgb.c:143
static void msgb_put_u32(struct msgb *msgb, uint32_t word)
append a uint32 value to the end of the message
Definition: msgb.h:215
static unsigned char * msgb_pull(struct msgb *msgb, unsigned int len)
remove (pull) a header from the front of the message buffer
Definition: msgb.h:297
static void msgb_put_u8(struct msgb *msgb, uint8_t word)
append a uint8 value to the end of the message
Definition: msgb.h:195