ulut/ul_cbuff.h

   1 /*******************************************************************
   2   uLan Utilities Library - C library of basic reusable constructions
   3
   4   ul_cbuff.h    - circular buffer
   5
   6   (C) Copyright 2006 by Pavel Pisa - Originator
   7
   8   The uLan utilities library can be used, copied and modified under
   9   next licenses
  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.
  19
  20   See files COPYING and README for details.
  21
  22  *******************************************************************/
  23
  24 #ifndef _UL_CBUFF_H
  25 #define _UL_CBUFF_H
  26
  27 #include "ul_utdefs.h"
  28
  29 #include <string.h>
  30
  31 #ifdef __cplusplus
  32 extern "C" {
  33 #endif
  34
  35 #define UL_CBUFF_NO_INLINE
  36
  37 #ifndef UL_CBUFF_NO_INLINE
  38 #define UL_CBUFF_INLINE
  39 #endif
  40
  41 #ifndef ul_cbuff_inline
  42 #ifdef UL_CBUFF_INLINE
  43 #define ul_cbuff_inline static inline
  44 #else
  45 #define ul_cbuff_inline
  46 #endif
  47 #endif
  48
  49 #define ul_cbuff_align(x) (((x)+3)&~3)
  50
  51 typedef unsigned int ul_cbuff_loc_t;
  52
  53 typedef struct ul_cbuff_msg_head_t {
  54   unsigned short flags;
  55   unsigned short length;
  56 } ul_cbuff_msg_head_t;
  57
  58 #define UL_CBUFF_MSG_READY    0x8000
  59 #define UL_CBUFF_MSG_OVERFLOW 0x4000
  60 #define UL_CBUFF_MSG_READERS  0x3fff
  61
  62 #define ul_cbuff_msg_head_size (ul_cbuff_align(sizeof(ul_cbuff_msg_head_t)))
  63
  64 typedef struct ul_cbuff_state_t {
  65   ul_cbuff_loc_t buff_size;
  66   ul_cbuff_loc_t head;
  67   ul_cbuff_loc_t lasttail;
  68   ul_cbuff_loc_t firsttail;
  69   unsigned int   cycles;
  70   unsigned int   readers;
  71   ul_cbuff_loc_t rear_size;
  72 } ul_cbuff_state_t;
  73
  74 typedef struct ul_cbuff_t {
  75   unsigned char    *buff_start;
  76   ul_cbuff_state_t *state;
  77 } ul_cbuff_t;
  78
  79 typedef struct ul_cbuff_data_info_t {
  80   unsigned char *ptr;
  81   unsigned char *wrap_ptr;
  82   unsigned int  cont_len;
  83   unsigned int  wrap_len;
  84 } ul_cbuff_data_info_t;
  85
  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;
  90
  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;
  95
  96 #if !defined(UL_CBUFF_INLINE)
  97
  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);
 117
 118 #endif /* UL_CBUFF_INLINE */
 119
 120 #if defined(UL_CBUFF_INLINE) || defined(UL_CBUFF_INCLUDE_INTERNAL)
 121
 122 ul_cbuff_inline void
 123 ul_cbuff_mark_ready(ul_cbuff_msg_head_t *msg)
 124 {
 125   msg->flags|=UL_CBUFF_MSG_READY;
 126 }
 127
 128 ul_cbuff_inline int
 129 ul_cbuff_is_ready(const ul_cbuff_msg_head_t *msg)
 130 {
 131   return msg->flags&UL_CBUFF_MSG_READY;
 132 }
 133
 134 ul_cbuff_inline int
 135 ul_cbuff_head_alloc(ul_cbuff_t *buff, ul_cbuff_put_info_t *put_info, unsigned int size, unsigned int flags)
 136 {
 137   ul_cbuff_state_t *state=buff->state;
 138   unsigned int length=size;
 139
 140   size=ul_cbuff_align(size+state->rear_size)+ul_cbuff_msg_head_size;
 141
 142   if((state->lasttail > state->head) &&
 143      (state->lasttail-state->head <= size))
 144       return -1;
 145
 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);
 149
 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;
 154
 155     state->head+=size;
 156   }else{
 157     ul_cbuff_loc_t res_size=state->buff_size-state->head;
 158     if(size-res_size >= state->lasttail)
 159       return -1;
 160
 161     put_info->msg_head=(ul_cbuff_msg_head_t *)(buff->buff_start+state->head);
 162
 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;
 169       }else{
 170         put_info->data.wrap_ptr=NULL;
 171         put_info->data.wrap_len=0;
 172       }
 173     }else{
 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;
 178     }
 179
 180     state->cycles++;
 181     state->head=size-res_size;
 182   }
 183
 184   ((ul_cbuff_msg_head_t *)(buff->buff_start+state->head))->flags=0;
 185
 186   flags&=~(UL_CBUFF_MSG_READY|UL_CBUFF_MSG_READERS);
 187
 188   put_info->msg_head->flags|=flags;
 189   if(buff->state->readers>0)
 190     put_info->msg_head->flags+=buff->state->readers;
 191
 192   put_info->msg_head->length=length;
 193
 194   return 0;
 195 }
 196
 197 ul_cbuff_inline int
 198 ul_cbuff_head_put(ul_cbuff_t *buff, ul_cbuff_put_info_t *put_info)
 199 {
 200   ul_cbuff_mark_ready(put_info->msg_head);
 201   put_info->msg_head=NULL;
 202   return 0;
 203 }
 204
 205 ul_cbuff_inline ul_cbuff_loc_t
 206 ul_cbuff_head_loc(const ul_cbuff_t *buff, const ul_cbuff_msg_head_t *msg_head)
 207 {
 208   return (unsigned char*)msg_head-buff->buff_start;
 209 }
 210
 211 ul_cbuff_inline ul_cbuff_loc_t
 212 ul_cbuff_next_loc(const ul_cbuff_t *buff, const ul_cbuff_msg_head_t *msg_head)
 213 {
 214   ul_cbuff_loc_t loc;
 215   unsigned int size;
 216
 217   size=ul_cbuff_align(msg_head->length+buff->state->rear_size)+ul_cbuff_msg_head_size;
 218
 219   loc=(unsigned char*)msg_head-buff->buff_start;
 220   if(buff->state->buff_size-loc > size)
 221     loc+=size;
 222   else
 223     loc=size-(buff->state->buff_size-loc);
 224
 225   return loc;
 226 }
 227
 228 ul_cbuff_inline int
 229 ul_cbuff_msg_head2data(const ul_cbuff_t *buff, ul_cbuff_data_info_t *data, const ul_cbuff_msg_head_t *msg_head)
 230 {
 231   ul_cbuff_loc_t res_size;
 232   unsigned int length;
 233   ul_cbuff_loc_t msg_loc=(unsigned char *)msg_head-buff->buff_start;
 234
 235   res_size=buff->state->buff_size-msg_loc;
 236   length=msg_head->length;
 237
 238   if(res_size > ul_cbuff_msg_head_size){
 239     data->ptr=(unsigned char*)msg_head+ul_cbuff_msg_head_size;
 240     if(res_size-ul_cbuff_msg_head_size >= length){
 241       data->cont_len=length;
 242       data->wrap_ptr=NULL;
 243       data->wrap_len=0;
 244     }else{
 245       data->cont_len=res_size-ul_cbuff_msg_head_size;
 246       data->wrap_ptr=buff->buff_start;
 247       data->wrap_len=length-(res_size-ul_cbuff_msg_head_size);
 248     }
 249   } else {
 250     data->ptr=buff->buff_start;
 251     data->cont_len=length;
 252     data->wrap_ptr=NULL;
 253     data->wrap_len=0;
 254   }
 255   return msg_head->flags;
 256 }
 257
 258 ul_cbuff_inline int
 259 ul_cbuff_tail_attach(ul_cbuff_t *buff, ul_cbuff_tail_info_t *tail_info, int mode)
 260 {
 261   ul_cbuff_state_t *state=buff->state;
 262   ul_cbuff_msg_head_t *msg_head;
 263
 264   msg_head=(ul_cbuff_msg_head_t *)(buff->buff_start+state->head);
 265   if(state->readers>=0)
 266     state->readers++;
 267   tail_info->msg_head=msg_head;
 268   tail_info->data.ptr=NULL;
 269   return 0;
 270 }
 271
 272 ul_cbuff_inline int
 273 ul_cbuff_tail_incontact(ul_cbuff_t *buff, ul_cbuff_tail_info_t *tail_info)
 274 {
 275   if(tail_info->msg_head==NULL){
 276     return 0;
 277   }
 278   return 1;
 279 }
 280
 281 ul_cbuff_inline int
 282 ul_cbuff_tail_test(ul_cbuff_t *buff, ul_cbuff_tail_info_t *tail_info)
 283 {
 284   ul_cbuff_msg_head_t *msg_head=tail_info->msg_head;
 285
 286   if(!msg_head)
 287     return -1;
 288
 289   if(!ul_cbuff_is_ready(msg_head))
 290     return 0;
 291
 292   return ul_cbuff_msg_head2data(buff, &tail_info->data, msg_head);
 293 }
 294
 295 ul_cbuff_inline int
 296 ul_cbuff_tail_release(ul_cbuff_t *buff, ul_cbuff_tail_info_t *tail_info)
 297 {
 298   ul_cbuff_msg_head_t *msg_head=tail_info->msg_head;
 299   unsigned msg_readers;
 300
 301   if(!ul_cbuff_is_ready(msg_head))
 302     return -1;
 303
 304   if(buff->state->readers<=0)
 305     return 1;
 306
 307   msg_readers=msg_head->flags&UL_CBUFF_MSG_READERS;
 308   if(msg_readers)
 309     msg_head->flags--;
 310
 311   return msg_readers<=1?1:0;
 312 }
 313
 314 ul_cbuff_inline int
 315 ul_cbuff_tail_next(ul_cbuff_t *buff, ul_cbuff_tail_info_t *tail_info)
 316 {
 317   ul_cbuff_msg_head_t *msg_head=tail_info->msg_head;
 318
 319   if(!ul_cbuff_is_ready(msg_head))
 320     return -1;
 321
 322   tail_info->msg_head=(ul_cbuff_msg_head_t *)(buff->buff_start+
 323                         ul_cbuff_next_loc(buff, msg_head));
 324   return 0;
 325 }
 326
 327 ul_cbuff_inline int
 328 ul_cbuff_tail_state_update(ul_cbuff_t *buff, int release_result, ul_cbuff_loc_t loc, ul_cbuff_loc_t loc_next)
 329 {
 330   if(loc==buff->state->firsttail)
 331     buff->state->firsttail=loc_next;
 332
 333   if(release_result<=0)
 334     return 0;
 335
 336   if(loc==buff->state->lasttail){
 337     buff->state->lasttail=loc_next;
 338     return 1;
 339   }else{
 340     return -1;
 341   }
 342 }
 343
 344 ul_cbuff_inline void
 345 ul_cbuff_data_do_wrap(ul_cbuff_data_info_t *data_info)
 346 {
 347   data_info->ptr=data_info->wrap_ptr;
 348   data_info->cont_len=data_info->wrap_len;
 349   data_info->wrap_ptr=NULL;
 350   data_info->wrap_len=0;
 351 }
 352
 353 ul_cbuff_inline int
 354 ul_cbuff_data_at_once(ul_cbuff_data_info_t *data_info, void **pptr, int size)
 355 {
 356   int cont_len;
 357
 358   *pptr=data_info->ptr;
 359   if(!data_info->ptr)
 360     return 0;
 361   cont_len=data_info->cont_len;
 362   if(cont_len>size){
 363     cont_len=size;
 364     data_info->ptr+=size;
 365     data_info->cont_len-=cont_len;
 366   }else{
 367     ul_cbuff_data_do_wrap(data_info);
 368   }
 369   return cont_len;
 370 }
 371
 372 ul_cbuff_inline int
 373 ul_cbuff_put_data(ul_cbuff_data_info_t *data_info, const void *data, int size)
 374 {
 375   void *ptr;
 376   int count;
 377   int cont_len;
 378
 379   ptr=data_info->ptr;
 380   if(!ptr)
 381     return 0;
 382   cont_len=data_info->cont_len;
 383   if(cont_len>size){
 384     cont_len=size;
 385     data_info->ptr+=size;
 386     data_info->cont_len-=cont_len;
 387   }else{
 388     ul_cbuff_data_do_wrap(data_info);
 389   }
 390   if(cont_len<=0)
 391     return 0;
 392   memcpy(ptr,data,cont_len);
 393   count=cont_len;
 394   cont_len=size-cont_len;
 395   if(!cont_len)
 396     return count;
 397
 398   ptr=data_info->ptr;
 399   if(!ptr)
 400     return count;
 401   data=(char*)data+count;
 402   if(cont_len>data_info->cont_len)
 403     cont_len=data_info->cont_len;
 404   data_info->ptr+=cont_len;
 405   data_info->cont_len-=cont_len;
 406   memcpy(ptr,data,cont_len);
 407
 408   return cont_len+count;
 409 }
 410
 411 ul_cbuff_inline int
 412 ul_cbuff_get_data(ul_cbuff_data_info_t *data_info, void *data, int size)
 413 {
 414   void *ptr;
 415   int count;
 416   int cont_len;
 417
 418   ptr=data_info->ptr;
 419   if(!ptr)
 420     return 0;
 421   cont_len=data_info->cont_len;
 422   if(cont_len>size){
 423     cont_len=size;
 424     data_info->ptr+=size;
 425     data_info->cont_len-=cont_len;
 426   }else{
 427     ul_cbuff_data_do_wrap(data_info);
 428   }
 429   if(cont_len<=0)
 430     return 0;
 431   memcpy(data,ptr,cont_len);
 432   count=cont_len;
 433   cont_len=size-cont_len;
 434   if(!cont_len)
 435     return count;
 436
 437   ptr=data_info->ptr;
 438   if(!ptr)
 439     return count;
 440   data=(char*)data+count;
 441   if(cont_len>data_info->cont_len)
 442     cont_len=data_info->cont_len;
 443   data_info->ptr+=cont_len;
 444   data_info->cont_len-=cont_len;
 445   memcpy(data,ptr,cont_len);
 446
 447   return cont_len+count;
 448 }
 449
 450
 451 ul_cbuff_inline void *
 452 ul_cbuff_get_rear_ptr(ul_cbuff_t *buff, ul_cbuff_msg_head_t *msg_head)
 453 {
 454   ul_cbuff_loc_t loc;
 455   unsigned int size;
 456   ul_cbuff_state_t *state=buff->state;
 457
 458   size=ul_cbuff_align(msg_head->length+state->rear_size)+ul_cbuff_msg_head_size;
 459   size-=state->rear_size;
 460
 461   loc=(unsigned char*)msg_head-buff->buff_start;
 462   if(state->buff_size-loc > size)
 463     loc+=size;
 464   else
 465     loc=size-(state->buff_size-loc);
 466
 467   return buff->buff_start+loc;
 468 }
 469
 470 ul_cbuff_inline void *
 471 ul_cbuff_prev_rear_ptr(ul_cbuff_t *buff, ul_cbuff_loc_t loc)
 472 {
 473   ul_cbuff_state_t *state=buff->state;
 474
 475   if(loc>state->rear_size)
 476     return buff->buff_start+loc-state->rear_size;
 477   else
 478     return buff->buff_start+loc+state->buff_size-state->rear_size;
 479 }
 480
 481 #endif /*UL_CBUFF_INLINE*/
 482
 483 int ul_cbuff_init(ul_cbuff_t *buff, ul_cbuff_state_t *state,
 484                   void *buff_start, ul_cbuff_loc_t size);
 485
 486
 487 #ifdef __cplusplus
 488 } /* extern "C"*/
 489 #endif
 490
 491 #endif /* _UL_CBUFF_H */