libosmocore  0.9.6-10.20170220git32ee5af8.fc31
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 #include <osmocom/core/defs.h>
27 
40 #define MSGB_DEBUG
41 
43 struct msgb {
44  struct llist_head list;
47  /* Part of which TRX logical channel we were received / transmitted */
48  /* FIXME: move them into the control buffer */
49  union {
50  void *dst;
51  struct gsm_bts_trx *trx;
52  };
53  struct gsm_lchan *lchan;
55  unsigned char *l1h;
56  unsigned char *l2h;
57  unsigned char *l3h;
58  unsigned char *l4h;
60  unsigned long cb[5];
62  uint16_t data_len;
63  uint16_t len;
65  unsigned char *head;
66  unsigned char *tail;
67  unsigned char *data;
68  unsigned char _data[0];
69 };
70 
71 extern struct msgb *msgb_alloc(uint16_t size, const char *name);
72 extern void msgb_free(struct msgb *m);
73 extern void msgb_enqueue(struct llist_head *queue, struct msgb *msg);
74 extern struct msgb *msgb_dequeue(struct llist_head *queue);
75 extern void msgb_reset(struct msgb *m);
76 uint16_t msgb_length(const struct msgb *msg);
77 extern const char *msgb_hexdump(const struct msgb *msg);
78 extern int msgb_resize_area(struct msgb *msg, uint8_t *area,
79  int old_size, int new_size);
80 extern struct msgb *msgb_copy(const struct msgb *msg, const char *name);
81 static int msgb_test_invariant(const struct msgb *msg) __attribute__((pure));
82 
83 #ifdef MSGB_DEBUG
84 #include <osmocom/core/panic.h>
85 #define MSGB_ABORT(msg, fmt, args ...) do { \
86  osmo_panic("msgb(%p): " fmt, msg, ## args); \
87  } while(0)
88 #else
89 #define MSGB_ABORT(msg, fmt, args ...)
90 #endif
91 
93 #define msgb_l1(m) ((void *)(m->l1h))
94 
95 #define msgb_l2(m) ((void *)(m->l2h))
96 
97 #define msgb_l3(m) ((void *)(m->l3h))
98 
99 #define msgb_sms(m) ((void *)(m->l4h))
100 
108 static inline unsigned int msgb_l1len(const struct msgb *msgb)
109 {
110  return msgb->tail - (uint8_t *)msgb_l1(msgb);
111 }
112 
120 static inline unsigned int msgb_l2len(const struct msgb *msgb)
121 {
122  return msgb->tail - (uint8_t *)msgb_l2(msgb);
123 }
124 
132 static inline unsigned int msgb_l3len(const struct msgb *msgb)
133 {
134  return msgb->tail - (uint8_t *)msgb_l3(msgb);
135 }
136 
144 static inline unsigned int msgb_headlen(const struct msgb *msgb)
145 {
146  return msgb->len - msgb->data_len;
147 }
148 
156 static inline int msgb_tailroom(const struct msgb *msgb)
157 {
158  return (msgb->head + msgb->data_len) - msgb->tail;
159 }
160 
168 static inline int msgb_headroom(const struct msgb *msgb)
169 {
170  return (msgb->data - msgb->head);
171 }
172 
185 static inline unsigned char *msgb_put(struct msgb *msgb, unsigned int len)
186 {
187  unsigned char *tmp = msgb->tail;
188  if (msgb_tailroom(msgb) < (int) len)
189  MSGB_ABORT(msgb, "Not enough tailroom msgb_put (%u < %u)\n",
191  msgb->tail += len;
192  msgb->len += len;
193  return tmp;
194 }
195 
200 static inline void msgb_put_u8(struct msgb *msgb, uint8_t word)
201 {
202  uint8_t *space = msgb_put(msgb, 1);
203  space[0] = word & 0xFF;
204 }
205 
210 static inline void msgb_put_u16(struct msgb *msgb, uint16_t word)
211 {
212  uint8_t *space = msgb_put(msgb, 2);
213  osmo_store16be(word, space);
214 }
215 
220 static inline void msgb_put_u32(struct msgb *msgb, uint32_t word)
221 {
222  uint8_t *space = msgb_put(msgb, 4);
223  osmo_store32be(word, space);
224 }
225 
230 static inline unsigned char *msgb_get(struct msgb *msgb, unsigned int len)
231 {
232  unsigned char *tmp = msgb->tail - len;
233  if (msgb_length(msgb) < len)
234  MSGB_ABORT(msgb, "msgb too small to get %u (len %u)\n",
235  len, msgb_length(msgb));
236  msgb->tail -= len;
237  msgb->len -= len;
238  return tmp;
239 }
240 
245 static inline uint8_t msgb_get_u8(struct msgb *msgb)
246 {
247  uint8_t *space = msgb_get(msgb, 1);
248  return space[0];
249 }
250 
255 static inline uint16_t msgb_get_u16(struct msgb *msgb)
256 {
257  uint8_t *space = msgb_get(msgb, 2);
258  return osmo_load16be(space);
259 }
260 
265 static inline uint32_t msgb_get_u32(struct msgb *msgb)
266 {
267  uint8_t *space = msgb_get(msgb, 4);
268  return osmo_load32be(space);
269 }
270 
283 static inline unsigned char *msgb_push(struct msgb *msgb, unsigned int len)
284 {
285  if (msgb_headroom(msgb) < (int) len)
286  MSGB_ABORT(msgb, "Not enough headroom msgb_push (%u < %u)\n",
288  msgb->data -= len;
289  msgb->len += len;
290  return msgb->data;
291 }
292 
297 static inline void msgb_push_u8(struct msgb *msg, uint8_t word)
298 {
299  uint8_t *space = msgb_push(msg, 1);
300  space[0] = word;
301 }
302 
307 static inline void msgb_push_u16(struct msgb *msg, uint16_t word)
308 {
309  uint16_t *space = (uint16_t *) msgb_push(msg, 2);
310  osmo_store16be(word, space);
311 }
312 
317 static inline void msgb_push_u32(struct msgb *msg, uint32_t word)
318 {
319  uint32_t *space = (uint32_t *) msgb_push(msg, 4);
320  osmo_store32be(word, space);
321 }
322 
332 static inline unsigned char *msgb_pull(struct msgb *msgb, unsigned int len)
333 {
334  msgb->len -= len;
335  return msgb->data += len;
336 }
337 
346 static inline unsigned char *msgb_pull_to_l3(struct msgb *msg)
347 {
348  unsigned char *ret = msgb_pull(msg, msg->l3h - msg->data);
349  msg->l1h = msg->l2h = NULL;
350  return ret;
351 }
352 
357 static inline uint8_t msgb_pull_u8(struct msgb *msgb)
358 {
359  uint8_t *space = msgb_pull(msgb, 1) - 1;
360  return space[0];
361 }
362 
367 static inline uint16_t msgb_pull_u16(struct msgb *msgb)
368 {
369  uint8_t *space = msgb_pull(msgb, 2) - 2;
370  return osmo_load16be(space);
371 }
372 
377 static inline uint32_t msgb_pull_u32(struct msgb *msgb)
378 {
379  uint8_t *space = msgb_pull(msgb, 4) - 4;
380  return osmo_load32be(space);
381 }
382 
394 static inline void msgb_reserve(struct msgb *msg, int len)
395 {
396  msg->data += len;
397  msg->tail += len;
398 }
399 
405 static inline int msgb_trim(struct msgb *msg, int len)
406 {
407  if (len < 0)
408  MSGB_ABORT(msg, "Negative length is not allowed\n");
409  if (len > msg->data_len)
410  return -1;
411 
412  msg->len = len;
413  msg->tail = msg->data + len;
414 
415  return 0;
416 }
417 
423 static inline int msgb_l3trim(struct msgb *msg, int l3len)
424 {
425  return msgb_trim(msg, (msg->l3h - msg->data) + l3len);
426 }
427 
438 static inline struct msgb *msgb_alloc_headroom(int size, int headroom,
439  const char *name)
440 {
441  osmo_static_assert(size > headroom, headroom_bigger);
442 
443  struct msgb *msg = msgb_alloc(size, name);
444  if (msg)
445  msgb_reserve(msg, headroom);
446  return msg;
447 }
448 
453 static inline int msgb_test_invariant(const struct msgb *msg)
454 {
455  const unsigned char *lbound;
456  if (!msg || !msg->data || !msg->tail ||
457  (msg->data + msg->len != msg->tail) ||
458  (msg->data < msg->head) ||
459  (msg->tail > msg->head + msg->data_len))
460  return 0;
461 
462  lbound = msg->head;
463 
464  if (msg->l1h) {
465  if (msg->l1h < lbound)
466  return 0;
467  lbound = msg->l1h;
468  }
469  if (msg->l2h) {
470  if (msg->l2h < lbound)
471  return 0;
472  lbound = msg->l2h;
473  }
474  if (msg->l3h) {
475  if (msg->l3h < lbound)
476  return 0;
477  lbound = msg->l3h;
478  }
479  if (msg->l4h) {
480  if (msg->l4h < lbound)
481  return 0;
482  lbound = msg->l4h;
483  }
484 
485  return lbound <= msg->head + msg->data_len;
486 }
487 
488 /* non inline functions to ease binding */
489 
490 uint8_t *msgb_data(const struct msgb *msg);
491 
492 void *msgb_talloc_ctx_init(void *root_ctx, unsigned int pool_size);
493 void msgb_set_talloc_ctx(void *ctx) OSMO_DEPRECATED("Use msgb_talloc_ctx_init() instead");
494 
static unsigned char * msgb_put(struct msgb *msgb, unsigned int len)
append data to end of message buffer
Definition: msgb.h:185
static uint16_t msgb_pull_u16(struct msgb *msgb)
remove uint16 from front of message
Definition: msgb.h:367
static unsigned int msgb_l3len(const struct msgb *msgb)
determine length of L3 message
Definition: msgb.h:132
unsigned long cb[5]
control buffer
Definition: msgb.h:60
#define OSMO_DEPRECATED(text)
Set the deprecated attribute with a message.
Definition: defs.h:41
unsigned char * l3h
pointer to Layer 3 header. For OML: FOM; RSL: 04.08; GPRS: BSSGP
Definition: msgb.h:57
#define msgb_l3(m)
obtain L3 header of msgb
Definition: msgb.h:97
#define msgb_l1(m)
obtain L1 header of msgb
Definition: msgb.h:93
struct msgb * msgb_alloc(uint16_t size, const char *name)
Allocate a new message buffer.
Definition: msgb.c:49
unsigned char * data
start of message in buffer
Definition: msgb.h:67
Osmocom message buffer.
Definition: msgb.h:43
void msgb_set_talloc_ctx(void *ctx) OSMO_DEPRECATED("Use msgb_talloc_ctx_init() instead")
Set the talloc context for msgb_alloc Deprecated, use msgb_talloc_ctx_init() instead.
Definition: msgb.c:157
static int msgb_l3trim(struct msgb *msg, int l3len)
Trim the msgb to a given layer3 length.
Definition: msgb.h:423
General definitions that are meant to be included from header files.
static int msgb_trim(struct msgb *msg, int len)
Trim the msgb to a given absolute length.
Definition: msgb.h:405
uint16_t len
length of bytes used in msgb
Definition: msgb.h:63
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:346
void msgb_free(struct msgb *m)
Release given message buffer.
Definition: msgb.c:72
static int msgb_tailroom(const struct msgb *msgb)
determine how much tail room is left in msgb
Definition: msgb.h:156
unsigned char * l4h
pointer to layer 4 header
Definition: msgb.h:58
static unsigned int msgb_l1len(const struct msgb *msgb)
determine length of L1 message
Definition: msgb.h:108
static unsigned char * msgb_get(struct msgb *msgb, unsigned int len)
remove data from end of message
Definition: msgb.h:230
const char * msgb_hexdump(const struct msgb *msg)
Return a (static) buffer containing a hexdump of the msg.
Definition: msgb.c:275
static void msgb_push_u8(struct msgb *msg, uint8_t word)
prepend a uint8 value to the head of the message
Definition: msgb.h:297
struct msgb * msgb_dequeue(struct llist_head *queue)
Dequeue message buffer from head of queue.
Definition: msgb.c:96
void * msgb_talloc_ctx_init(void *root_ctx, unsigned int pool_size)
Initialize a msgb talloc context for msgb_alloc. Create a talloc context called "msgb". If pool_size is 0, create a named const as msgb talloc context. If pool_size is nonzero, create a talloc pool, possibly for faster msgb allocations (see talloc_pool()).
Definition: msgb.c:170
int msgb_resize_area(struct msgb *msg, uint8_t *area, int old_size, int new_size)
Resize an area within an msgb.
Definition: msgb.c:230
static uint32_t msgb_pull_u32(struct msgb *msgb)
remove uint32 from front of message
Definition: msgb.h:377
static unsigned int msgb_l2len(const struct msgb *msgb)
determine length of L2 message
Definition: msgb.h:120
static struct msgb * msgb_alloc_headroom(int size, int headroom, const char *name)
Allocate message buffer with specified headroom.
Definition: msgb.h:438
static unsigned char * msgb_push(struct msgb *msgb, unsigned int len)
prepend (push) some data to start of message
Definition: msgb.h:283
Simple doubly linked list implementation.
(double) linked list header structure
Definition: linuxlist.h:47
unsigned char * l1h
pointer to Layer1 header (if any)
Definition: msgb.h:55
static uint8_t msgb_pull_u8(struct msgb *msgb)
remove uint8 from front of message
Definition: msgb.h:357
void msgb_enqueue(struct llist_head *queue, struct msgb *msg)
Enqueue message buffer to tail of a queue.
Definition: msgb.c:84
struct gsm_lchan * lchan
logical channel
Definition: msgb.h:53
void msgb_reset(struct msgb *m)
Re-set all message buffer pointers.
Definition: msgb.c:119
static void msgb_push_u32(struct msgb *msg, uint32_t word)
prepend a uint32 value to the head of the message
Definition: msgb.h:317
static void msgb_reserve(struct msgb *msg, int len)
Increase headroom of empty msgb, reducing the tailroom.
Definition: msgb.h:394
unsigned char * tail
end of message in buffer
Definition: msgb.h:66
static void msgb_put_u16(struct msgb *msgb, uint16_t word)
append a uint16 value to the end of the message
Definition: msgb.h:210
static uint8_t msgb_get_u8(struct msgb *msgb)
remove uint8 from end of message
Definition: msgb.h:245
unsigned char * l2h
pointer to A-bis layer 2 header: OML, RSL(RLL), NS
Definition: msgb.h:56
struct msgb * msgb_copy(const struct msgb *msg, const char *name)
Copy an msgb.
Definition: msgb.c:188
unsigned char * head
start of underlying memory buffer
Definition: msgb.h:65
static uint32_t msgb_get_u32(struct msgb *msgb)
remove uint32 from end of message
Definition: msgb.h:265
static int msgb_headroom(const struct msgb *msgb)
determine the amount of headroom in msgb
Definition: msgb.h:168
Osmocom bit level support code.
uint16_t data_len
length of underlying data array
Definition: msgb.h:62
unsigned char _data[0]
optional immediate data array
Definition: msgb.h:68
struct llist_head list
linked list header
Definition: msgb.h:44
uint8_t * msgb_data(const struct msgb *msg)
get pointer to data section of message buffer
Definition: msgb.c:139
#define msgb_l2(m)
obtain L2 header of msgb
Definition: msgb.h:95
static uint16_t msgb_get_u16(struct msgb *msgb)
remove uint16 from end of message
Definition: msgb.h:255
void * dst
reference of origin/destination
Definition: msgb.h:50
static unsigned int msgb_headlen(const struct msgb *msgb)
determine the length of the header
Definition: msgb.h:144
uint16_t msgb_length(const struct msgb *msg)
get length of message buffer
Definition: msgb.c:148
static int msgb_test_invariant(const struct msgb *msg) __attribute__((pure))
Check a message buffer for consistency.
Definition: msgb.h:453
static void msgb_put_u32(struct msgb *msgb, uint32_t word)
append a uint32 value to the end of the message
Definition: msgb.h:220
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:332
static void msgb_push_u16(struct msgb *msg, uint16_t word)
prepend a uint16 value to the head of the message
Definition: msgb.h:307
static void msgb_put_u8(struct msgb *msgb, uint8_t word)
append a uint8 value to the end of the message
Definition: msgb.h:200