1 /*******************************************************************
2 uLan Utilities Library - C library of basic reusable constructions
4 ul_cbuff.h - circular buffer
6 (C) Copyright 2006 by Pavel Pisa - Originator
8 The uLan utilities library can be used, copied and modified under
10 - GPL - GNU General Public License
11 - LGPL - GNU Lesser General Public License
12 - MPL - Mozilla Public License
13 - and other licenses added by project originators
14 Code can be modified and re-distributed under any combination
15 of the above listed licenses. If contributor does not agree with
16 some of the licenses, he/she can delete appropriate line.
17 Warning, if you delete all lines, you are not allowed to
18 distribute source code and/or binaries utilizing code.
20 See files COPYING and README for details.
22 *******************************************************************/
27 #include "ul_utdefs.h"
35 #define UL_CBUFF_NO_INLINE
37 #ifndef UL_CBUFF_NO_INLINE
38 #define UL_CBUFF_INLINE
41 #ifndef ul_cbuff_inline
42 #ifdef UL_CBUFF_INLINE
43 #define ul_cbuff_inline static inline
45 #define ul_cbuff_inline
49 #define ul_cbuff_align(x) (((x)+3)&~3)
51 typedef unsigned int ul_cbuff_loc_t;
53 typedef struct ul_cbuff_msg_head_t {
55 unsigned short length;
56 } ul_cbuff_msg_head_t;
58 #define UL_CBUFF_MSG_READY 0x8000
59 #define UL_CBUFF_MSG_OVERFLOW 0x4000
60 #define UL_CBUFF_MSG_READERS 0x3fff
62 #define ul_cbuff_msg_head_size (ul_cbuff_align(sizeof(ul_cbuff_msg_head_t)))
64 typedef struct ul_cbuff_state_t {
65 ul_cbuff_loc_t buff_size;
67 ul_cbuff_loc_t lasttail;
68 ul_cbuff_loc_t firsttail;
71 ul_cbuff_loc_t rear_size;
74 typedef struct ul_cbuff_t {
75 unsigned char *buff_start;
76 ul_cbuff_state_t *state;
79 typedef struct ul_cbuff_data_info_t {
81 unsigned char *wrap_ptr;
82 unsigned int cont_len;
83 unsigned int wrap_len;
84 } ul_cbuff_data_info_t;
86 typedef struct ul_cbuff_put_info_t {
87 ul_cbuff_data_info_t data;
88 ul_cbuff_msg_head_t *msg_head;
89 } ul_cbuff_put_info_t;
91 typedef struct ul_cbuff_tail_info_t {
92 ul_cbuff_data_info_t data;
93 ul_cbuff_msg_head_t *msg_head;
94 } ul_cbuff_tail_info_t;
96 #if !defined(UL_CBUFF_INLINE)
98 void ul_cbuff_mark_ready(ul_cbuff_msg_head_t *msg);
99 int ul_cbuff_is_ready(const ul_cbuff_msg_head_t *msg);
100 int ul_cbuff_head_alloc(ul_cbuff_t *buff, ul_cbuff_put_info_t *put_info, unsigned int size, unsigned int flags);
101 int ul_cbuff_head_put(ul_cbuff_t *buff, ul_cbuff_put_info_t *put_info);
102 ul_cbuff_loc_t ul_cbuff_head_loc(const ul_cbuff_t *buff, const ul_cbuff_msg_head_t *msg_head);
103 ul_cbuff_loc_t ul_cbuff_next_loc(const ul_cbuff_t *buff, const ul_cbuff_msg_head_t *msg_head);
104 int ul_cbuff_msg_head2data(const ul_cbuff_t *buff, ul_cbuff_data_info_t *data, const ul_cbuff_msg_head_t *msg_head);
105 int ul_cbuff_tail_attach(ul_cbuff_t *buff, ul_cbuff_tail_info_t *tail_info, int mode);
106 int ul_cbuff_tail_incontact(ul_cbuff_t *buff, ul_cbuff_tail_info_t *tail_info);
107 int ul_cbuff_tail_test(ul_cbuff_t *buff, ul_cbuff_tail_info_t *tail_info);
108 int ul_cbuff_tail_release(ul_cbuff_t *buff, ul_cbuff_tail_info_t *tail_info);
109 int ul_cbuff_tail_next(ul_cbuff_t *buff, ul_cbuff_tail_info_t *tail_info);
110 int ul_cbuff_tail_state_update(ul_cbuff_t *buff, int release_result, ul_cbuff_loc_t loc, ul_cbuff_loc_t loc_next);
111 void ul_cbuff_data_do_wrap(ul_cbuff_data_info_t *data_info);
112 int ul_cbuff_data_at_once(ul_cbuff_data_info_t *data_info, void **pptr, int size);
113 int ul_cbuff_put_data(ul_cbuff_data_info_t *data_info, const void *data, int size);
114 int ul_cbuff_get_data(ul_cbuff_data_info_t *data_info, void *data, int size);
115 void *ul_cbuff_get_rear_ptr(ul_cbuff_t *buff, ul_cbuff_msg_head_t *msg_head);
116 void *ul_cbuff_prev_rear_ptr(ul_cbuff_t *buff, ul_cbuff_loc_t loc);
118 #endif /* UL_CBUFF_INLINE */
120 #if defined(UL_CBUFF_INLINE) || defined(UL_CBUFF_INCLUDE_INTERNAL)
123 ul_cbuff_mark_ready(ul_cbuff_msg_head_t *msg)
125 msg->flags|=UL_CBUFF_MSG_READY;
129 ul_cbuff_is_ready(const ul_cbuff_msg_head_t *msg)
131 return msg->flags&UL_CBUFF_MSG_READY;
135 ul_cbuff_head_alloc(ul_cbuff_t *buff, ul_cbuff_put_info_t *put_info, unsigned int size, unsigned int flags)
137 ul_cbuff_state_t *state=buff->state;
138 unsigned int length=size;
140 size=ul_cbuff_align(size+state->rear_size)+ul_cbuff_msg_head_size;
142 if((state->lasttail > state->head) &&
143 (state->lasttail-state->head <= size))
146 if((state->lasttail > state->head) ||
147 (state->buff_size-state->head > size)){
148 put_info->msg_head=(ul_cbuff_msg_head_t *)(buff->buff_start+state->head);
150 put_info->data.ptr=(buff->buff_start+state->head+ul_cbuff_msg_head_size);
151 put_info->data.cont_len=length;
152 put_info->data.wrap_ptr=NULL;
153 put_info->data.wrap_len=0;
157 ul_cbuff_loc_t res_size=state->buff_size-state->head;
158 if(size-res_size >= state->lasttail)
161 put_info->msg_head=(ul_cbuff_msg_head_t *)(buff->buff_start+state->head);
163 if(res_size != ul_cbuff_msg_head_size){
164 put_info->data.ptr=(buff->buff_start+state->head+ul_cbuff_msg_head_size);
165 put_info->data.cont_len=res_size-ul_cbuff_msg_head_size;
166 if(put_info->data.cont_len<length){
167 put_info->data.wrap_ptr=buff->buff_start;
168 put_info->data.wrap_len=length-put_info->data.cont_len;
170 put_info->data.wrap_ptr=NULL;
171 put_info->data.wrap_len=0;
174 put_info->data.ptr=buff->buff_start;
175 put_info->data.cont_len=length;
176 put_info->data.wrap_ptr=NULL;
177 put_info->data.wrap_len=0;
181 state->head=size-res_size;
184 ((ul_cbuff_msg_head_t *)(buff->buff_start+state->head))->flags=0;
186 put_info->msg_head->flags|=flags;
187 put_info->msg_head->length=length;
193 ul_cbuff_head_put(ul_cbuff_t *buff, ul_cbuff_put_info_t *put_info)
195 if(buff->state->readers>0)
196 put_info->msg_head->flags+=buff->state->readers;
197 ul_cbuff_mark_ready(put_info->msg_head);
198 put_info->msg_head=NULL;
202 ul_cbuff_inline ul_cbuff_loc_t
203 ul_cbuff_head_loc(const ul_cbuff_t *buff, const ul_cbuff_msg_head_t *msg_head)
205 return (unsigned char*)msg_head-buff->buff_start;
208 ul_cbuff_inline ul_cbuff_loc_t
209 ul_cbuff_next_loc(const ul_cbuff_t *buff, const ul_cbuff_msg_head_t *msg_head)
214 size=ul_cbuff_align(msg_head->length+buff->state->rear_size)+ul_cbuff_msg_head_size;
216 loc=(unsigned char*)msg_head-buff->buff_start;
217 if(buff->state->buff_size-loc > size)
220 loc=size-(buff->state->buff_size-loc);
226 ul_cbuff_msg_head2data(const ul_cbuff_t *buff, ul_cbuff_data_info_t *data, const ul_cbuff_msg_head_t *msg_head)
228 ul_cbuff_loc_t res_size;
230 ul_cbuff_loc_t msg_loc=(unsigned char *)msg_head-buff->buff_start;
232 res_size=buff->state->buff_size-msg_loc;
233 length=msg_head->length;
235 if(res_size > ul_cbuff_msg_head_size){
236 data->ptr=(unsigned char*)msg_head+ul_cbuff_msg_head_size;
237 if(res_size-ul_cbuff_msg_head_size >= length){
238 data->cont_len=length;
242 data->cont_len=res_size-ul_cbuff_msg_head_size;
243 data->wrap_ptr=buff->buff_start;
244 data->wrap_len=length-(res_size-ul_cbuff_msg_head_size);
247 data->ptr=buff->buff_start;
248 data->cont_len=length;
252 return msg_head->flags;
256 ul_cbuff_tail_attach(ul_cbuff_t *buff, ul_cbuff_tail_info_t *tail_info, int mode)
258 ul_cbuff_state_t *state=buff->state;
259 ul_cbuff_msg_head_t *msg_head;
261 msg_head=(ul_cbuff_msg_head_t *)(buff->buff_start+state->head);
262 if(state->readers>=0)
264 if((state->readers<0)||(state->firsttail==state->head)){
265 tail_info->msg_head=msg_head;
266 tail_info->data.ptr=NULL;
268 /* There is already some message(s) write in progress */
269 tail_info->msg_head=NULL;
270 tail_info->msg_head->flags++;
271 /* Some data fields are abused for ready condition checking */
272 tail_info->data.ptr=(unsigned char*)msg_head;
273 tail_info->data.wrap_ptr=buff->buff_start+state->firsttail;
274 tail_info->data.wrap_len=state->cycles;
280 ul_cbuff_tail_incontact(ul_cbuff_t *buff, ul_cbuff_tail_info_t *tail_info)
282 if(tail_info->msg_head==NULL){
283 unsigned char *new_firsttail=buff->buff_start+buff->state->firsttail;
284 unsigned char *old_head=tail_info->data.ptr;
285 unsigned char *old_firsttail=tail_info->data.wrap_ptr;
286 unsigned int old_cycles=tail_info->data.wrap_len;
287 unsigned int new_cycles=buff->state->cycles;
289 if(old_firsttail<old_head){
290 if((new_firsttail<old_head)&&(new_cycles==old_cycles))
293 if(new_cycles==old_cycles)
295 if((new_firsttail<old_head)&&((new_cycles-old_cycles)==1))
298 tail_info->msg_head=(ul_cbuff_msg_head_t *)old_head;
305 ul_cbuff_tail_test(ul_cbuff_t *buff, ul_cbuff_tail_info_t *tail_info)
307 ul_cbuff_msg_head_t *msg_head=tail_info->msg_head;
312 if(!ul_cbuff_is_ready(msg_head))
315 return ul_cbuff_msg_head2data(buff, &tail_info->data, msg_head);
319 ul_cbuff_tail_release(ul_cbuff_t *buff, ul_cbuff_tail_info_t *tail_info)
321 ul_cbuff_msg_head_t *msg_head=tail_info->msg_head;
322 unsigned msg_readers;
324 if(!ul_cbuff_is_ready(msg_head))
327 if(buff->state->readers<=0)
330 msg_readers=msg_head->flags&UL_CBUFF_MSG_READERS;
334 return msg_readers<=1?1:0;
338 ul_cbuff_tail_next(ul_cbuff_t *buff, ul_cbuff_tail_info_t *tail_info)
340 ul_cbuff_msg_head_t *msg_head=tail_info->msg_head;
342 if(!ul_cbuff_is_ready(msg_head))
345 tail_info->msg_head=(ul_cbuff_msg_head_t *)(buff->buff_start+
346 ul_cbuff_next_loc(buff, msg_head));
351 ul_cbuff_tail_state_update(ul_cbuff_t *buff, int release_result, ul_cbuff_loc_t loc, ul_cbuff_loc_t loc_next)
353 if(loc==buff->state->firsttail)
354 buff->state->firsttail=loc_next;
356 if(release_result<=0)
359 if(loc==buff->state->lasttail){
360 buff->state->lasttail=loc_next;
368 ul_cbuff_data_do_wrap(ul_cbuff_data_info_t *data_info)
370 data_info->ptr=data_info->wrap_ptr;
371 data_info->cont_len=data_info->wrap_len;
372 data_info->wrap_ptr=NULL;
373 data_info->wrap_len=0;
377 ul_cbuff_data_at_once(ul_cbuff_data_info_t *data_info, void **pptr, int size)
381 *pptr=data_info->ptr;
384 cont_len=data_info->cont_len;
387 data_info->ptr+=size;
388 data_info->cont_len-=cont_len;
390 ul_cbuff_data_do_wrap(data_info);
396 ul_cbuff_put_data(ul_cbuff_data_info_t *data_info, const void *data, int size)
405 cont_len=data_info->cont_len;
408 data_info->ptr+=size;
409 data_info->cont_len-=cont_len;
411 ul_cbuff_data_do_wrap(data_info);
415 memcpy(ptr,data,cont_len);
417 cont_len=size-cont_len;
424 data=(char*)data+count;
425 if(cont_len>data_info->cont_len)
426 cont_len=data_info->cont_len;
427 data_info->ptr+=cont_len;
428 data_info->cont_len-=cont_len;
429 memcpy(ptr,data,cont_len);
431 return cont_len+count;
435 ul_cbuff_get_data(ul_cbuff_data_info_t *data_info, void *data, int size)
444 cont_len=data_info->cont_len;
447 data_info->ptr+=size;
448 data_info->cont_len-=cont_len;
450 ul_cbuff_data_do_wrap(data_info);
454 memcpy(data,ptr,cont_len);
456 cont_len=size-cont_len;
463 data=(char*)data+count;
464 if(cont_len>data_info->cont_len)
465 cont_len=data_info->cont_len;
466 data_info->ptr+=cont_len;
467 data_info->cont_len-=cont_len;
468 memcpy(data,ptr,cont_len);
470 return cont_len+count;
474 ul_cbuff_inline void *
475 ul_cbuff_get_rear_ptr(ul_cbuff_t *buff, ul_cbuff_msg_head_t *msg_head)
479 ul_cbuff_state_t *state=buff->state;
481 size=ul_cbuff_align(msg_head->length+state->rear_size)+ul_cbuff_msg_head_size;
482 size-=state->rear_size;
484 loc=(unsigned char*)msg_head-buff->buff_start;
485 if(state->buff_size-loc > size)
488 loc=size-(state->buff_size-loc);
490 return buff->buff_start+loc;
493 ul_cbuff_inline void *
494 ul_cbuff_prev_rear_ptr(ul_cbuff_t *buff, ul_cbuff_loc_t loc)
496 ul_cbuff_state_t *state=buff->state;
498 if(loc>state->rear_size)
499 return buff->buff_start+loc-state->rear_size;
501 return buff->buff_start+loc+state->buff_size-state->rear_size;
504 #endif /*UL_CBUFF_INLINE*/
506 int ul_cbuff_init(ul_cbuff_t *buff, ul_cbuff_state_t *state,
507 void *buff_start, ul_cbuff_loc_t size);
514 #endif /* _UL_CBUFF_H */