@ECHO OFF REM Command file for Sphinx documentation if "%SPHINXBUILD%" == "" ( set SPHINXBUILD=sphinx-build ) set BUILDDIR=_build set ALLSPHINXOPTS=-d %BUILDDIR%/doctrees %SPHINXOPTS% . set I18NSPHINXOPTS=%SPHINXOPTS% . if NOT "%PAPER%" == "" ( set ALLSPHINXOPTS=-D latex_paper_size=%PAPER% %ALLSPHINXOPTS% set I18NSPHINXOPTS=-D latex_paper_size=%PAPER% %I18NSPHINXOPTS% ) if "%1" == "" goto help if "%1" == "help" ( :help echo.Please use `make ^` where ^ is one of echo. html to make standalone HTML files echo. dirhtml to make HTML files named index.html in directories echo. singlehtml to make a single large HTML file echo. pickle to make pickle files echo. json to make JSON files echo. htmlhelp to make HTML files and a HTML help project echo. qthelp to make HTML files and a qthelp project echo. devhelp to make HTML files and a Devhelp project echo. epub to make an epub echo. latex to make LaTeX files, you can set PAPER=a4 or PAPER=letter echo. text to make text files echo. man to make manual pages echo. texinfo to make Texinfo files echo. gettext to make PO message catalogs echo. changes to make an overview over all changed/added/deprecated items echo. linkcheck to check all external links for integrity echo. doctest to run all doctests embedded in the documentation if enabled goto end ) if "%1" == "clean" ( for /d %%i in (%BUILDDIR%\*) do rmdir /q /s %%i del /q /s %BUILDDIR%\* goto end ) if "%1" == "html" ( %SPHINXBUILD% -b html %ALLSPHINXOPTS% %BUILDDIR%/html if errorlevel 1 exit /b 1 echo. echo.Build finished. The HTML pages are in %BUILDDIR%/html. goto end ) if "%1" == "dirhtml" ( %SPHINXBUILD% -b dirhtml %ALLSPHINXOPTS% %BUILDDIR%/dirhtml if errorlevel 1 exit /b 1 echo. echo.Build finished. The HTML pages are in %BUILDDIR%/dirhtml. goto end ) if "%1" == "singlehtml" ( %SPHINXBUILD% -b singlehtml %ALLSPHINXOPTS% %BUILDDIR%/singlehtml if errorlevel 1 exit /b 1 echo. echo.Build finished. The HTML pages are in %BUILDDIR%/singlehtml. goto end ) if "%1" == "pickle" ( %SPHINXBUILD% -b pickle %ALLSPHINXOPTS% %BUILDDIR%/pickle if errorlevel 1 exit /b 1 echo. echo.Build finished; now you can process the pickle files. goto end ) if "%1" == "json" ( %SPHINXBUILD% -b json %ALLSPHINXOPTS% %BUILDDIR%/json if errorlevel 1 exit /b 1 echo. echo.Build finished; now you can process the JSON files. goto end ) if "%1" == "htmlhelp" ( %SPHINXBUILD% -b htmlhelp %ALLSPHINXOPTS% %BUILDDIR%/htmlhelp if errorlevel 1 exit /b 1 echo. echo.Build finished; now you can run HTML Help Workshop with the ^ .hhp project file in %BUILDDIR%/htmlhelp. goto end ) if "%1" == "qthelp" ( %SPHINXBUILD% -b qthelp %ALLSPHINXOPTS% %BUILDDIR%/qthelp if errorlevel 1 exit /b 1 echo. echo.Build finished; now you can run "qcollectiongenerator" with the ^ .qhcp project file in %BUILDDIR%/qthelp, like this: echo.^> qcollectiongenerator %BUILDDIR%\qthelp\Cryptography.qhcp echo.To view the help file: echo.^> assistant -collectionFile %BUILDDIR%\qthelp\Cryptography.ghc goto end ) if "%1" == "devhelp" ( %SPHINXBUILD% -b devhelp %ALLSPHINXOPTS% %BUILDDIR%/devhelp if errorlevel 1 exit /b 1 echo. echo.Build finished. goto end ) if "%1" == "epub" ( %SPHINXBUILD% -b epub %ALLSPHINXOPTS% %BUILDDIR%/epub if errorlevel 1 exit /b 1 echo. echo.Build finished. The epub file is in %BUILDDIR%/epub. goto end ) if "%1" == "latex" ( %SPHINXBUILD% -b latex %ALLSPHINXOPTS% %BUILDDIR%/latex if errorlevel 1 exit /b 1 echo. echo.Build finished; the LaTeX files are in %BUILDDIR%/latex. goto end ) if "%1" == "text" ( %SPHINXBUILD% -b text %ALLSPHINXOPTS% %BUILDDIR%/text if errorlevel 1 exit /b 1 echo. echo.Build finished. The text files are in %BUILDDIR%/text. goto end ) if "%1" == "man" ( %SPHINXBUILD% -b man %ALLSPHINXOPTS% %BUILDDIR%/man if errorlevel 1 exit /b 1 echo. echo.Build finished. The manual pages are in %BUILDDIR%/man. goto end ) if "%1" == "texinfo" ( %SPHINXBUILD% -b texinfo %ALLSPHINXOPTS% %BUILDDIR%/texinfo if errorlevel 1 exit /b 1 echo. echo.Build finished. The Texinfo files are in %BUILDDIR%/texinfo. goto end ) if "%1" == "gettext" ( %SPHINXBUILD% -b gettext %I18NSPHINXOPTS% %BUILDDIR%/locale if errorlevel 1 exit /b 1 echo. echo.Build finished. The message catalogs are in %BUILDDIR%/locale. goto end ) if "%1" == "changes" ( %SPHINXBUILD% -b changes %ALLSPHINXOPTS% %BUILDDIR%/changes if errorlevel 1 exit /b 1 echo. echo.The overview file is in %BUILDDIR%/changes. goto end ) if "%1" == "linkcheck" ( %SPHINXBUILD% -b linkcheck %ALLSPHINXOPTS% %BUILDDIR%/linkcheck if errorlevel 1 exit /b 1 echo. echo.Link check complete; look for any errors in the above output ^ or in %BUILDDIR%/linkcheck/output.txt. goto end ) if "%1" == "doctest" ( %SPHINXBUILD% -b doctest %ALLSPHINXOPTS% %BUILDDIR%/doctest if errorlevel 1 exit /b 1 echo. echo.Testing of doctests in the sources finished, look at the ^ results in %BUILDDIR%/doctest/output.txt. goto end ) :end 5' href='#n55'>55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 76 77 78 79 80 81 82 83 84 85 86 87 88 89 90 91 92 93 94 95 96 97 98 99 100 101 102 103 104 105 106 107 108 109 110 111 112 113 114 115 116 117 118 119 120 121 122 123 124 125 126 127 128 129 130 131 132 133 134 135 136 137 138 139 140 141 142 143 144 145 146 147 148 149 150 151 152 153 154 155 156 157 158 159 160 161 162 163 164 165 166 167 168 169 170 171 172 173 174 175 176 177 178 179 180 181 182 183 184 185 186 187 188 189 190 191 192 193 194 195 196 197 198 199 200 201 202 203 204 205 206 207 208 209 210 211 212 213 214 215 216 217 218 219 220 221 222 223 224 225 226 227 228 229 230 231 232 233 234 235 236 237 238 239 240 241 242 243 244 245 246 247 248 249 250 251 252 253 254 255 256 257 258 259 260 261 262 263 264 265 266 267 268 269 270 271 272 273 274 275 276 277 278 279 280 281 282 283 284 285 286 287 288 289 290 291 292 293 294 295 296 297 298 299 300 301 302 303 304 305 306 307 308 309 310 311 312 313 314 315 316 317 318 319 320 321 322 323 324 325 326 327 328 329 330 331 332 333 334 335 336 337 338 339 340 341 342 343 344 345 346 347 348 349 350 351 352 353 354 355 356 357 358 359 360 361 362 363 364 365 366 367 368 369 370 371 372 373 374 375 376 377 378 379 380 381 382 383 384 385 386 387 388 389 390 391 392 393 394 395 396 397 398 399 400 401 402 403 404 405 406 407 408 409 410 411 412 413 414 415 416 417 418 419 420 421 422 423 424 425 426 427 428 429 430 431 432 433 434 435 
/*
    ChibiOS - Copyright (C) 2006..2016 Giovanni Di Sirio.

    This file is part of ChibiOS.

    ChibiOS 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 3 of the License, or
    (at your option) any later version.

    ChibiOS 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, see <http://www.gnu.org/licenses/>.
*/

/**
 * @file    chmboxes.c
 * @brief   Mailboxes code.
 *
 * @addtogroup mailboxes
 * @details Asynchronous messages.
 *          <h2>Operation mode</h2>
 *          A mailbox is an asynchronous communication mechanism.<br>
 *          Operations defined for mailboxes:
 *          - <b>Post</b>: Posts a message on the mailbox in FIFO order.
 *          - <b>Post Ahead</b>: Posts a message on the mailbox with urgent
 *            priority.
 *          - <b>Fetch</b>: A message is fetched from the mailbox and removed
 *            from the queue.
 *          - <b>Reset</b>: The mailbox is emptied and all the stored messages
 *            are lost.
 *          .
 *          A message is a variable of type msg_t that is guaranteed to have
 *          the same size of and be compatible with (data) pointers (anyway an
 *          explicit cast is needed).
 *          If larger messages need to be exchanged then a pointer to a
 *          structure can be posted in the mailbox but the posting side has
 *          no predefined way to know when the message has been processed. A
 *          possible approach is to allocate memory (from a memory pool for
 *          example) from the posting side and free it on the fetching side.
 *          Another approach is to set a "done" flag into the structure pointed
 *          by the message.
 * @pre     In order to use the mailboxes APIs the @p CH_CFG_USE_MAILBOXES
 *          option must be enabled in @p chconf.h.
 * @note    Compatible with RT and NIL.
 * @{
 */

#include "ch.h"

#if (CH_CFG_USE_MAILBOXES == TRUE) || defined(__DOXYGEN__)

/*===========================================================================*/
/* Module exported variables.                                                */
/*===========================================================================*/

/*===========================================================================*/
/* Module local types.                                                       */
/*===========================================================================*/

/*===========================================================================*/
/* Module local variables.                                                   */
/*===========================================================================*/

/*===========================================================================*/
/* Module local functions.                                                   */
/*===========================================================================*/

/*===========================================================================*/
/* Module exported functions.                                                */
/*===========================================================================*/

/**
 * @brief   Initializes a @p mailbox_t object.
 *
 * @param[out] mbp      the pointer to the @p mailbox_t structure to be
 *                      initialized
 * @param[in] buf       pointer to the messages buffer as an array of @p msg_t
 * @param[in] n         number of elements in the buffer array
 *
 * @init
 */
void chMBObjectInit(mailbox_t *mbp, msg_t *buf, cnt_t n) {

  chDbgCheck((mbp != NULL) && (buf != NULL) && (n > (cnt_t)0));

  mbp->buffer = buf;
  mbp->rdptr = buf;
  mbp->wrptr = buf;
  mbp->top = &buf[n];
  chSemObjectInit(&mbp->emptysem, n);
  chSemObjectInit(&mbp->fullsem, (cnt_t)0);
}

/**
 * @brief   Resets a @p mailbox_t object.
 * @details All the waiting threads are resumed with status @p MSG_RESET and
 *          the queued messages are lost.
 *
 * @param[in] mbp       the pointer to an initialized @p mailbox_t object
 *
 * @api
 */
void chMBReset(mailbox_t *mbp) {

  chSysLock();
  chMBResetI(mbp);
  chSchRescheduleS();
  chSysUnlock();
}

/**
 * @brief   Resets a @p mailbox_t object.
 * @details All the waiting threads are resumed with status @p MSG_RESET and
 *          the queued messages are lost.
 *
 * @param[in] mbp       the pointer to an initialized @p mailbox_t object
 *
 * @api
 */
void chMBResetI(mailbox_t *mbp) {

  chDbgCheckClassI();
  chDbgCheck(mbp != NULL);

  mbp->wrptr = mbp->buffer;
  mbp->rdptr = mbp->buffer;
  chSemResetI(&mbp->emptysem, (cnt_t)(mbp->top - mbp->buffer));
  chSemResetI(&mbp->fullsem, (cnt_t)0);
}

/**
 * @brief   Posts a message into a mailbox.
 * @details The invoking thread waits until a empty slot in the mailbox becomes
 *          available or the specified time runs out.
 *
 * @param[in] mbp       the pointer to an initialized @p mailbox_t object
 * @param[in] msg       the message to be posted on the mailbox
 * @param[in] timeout   the number of ticks before the operation timeouts,
 *                      the following special values are allowed:
 *                      - @a TIME_IMMEDIATE immediate timeout.
 *                      - @a TIME_INFINITE no timeout.
 *                      .
 * @return              The operation status.
 * @retval MSG_OK       if a message has been correctly posted.
 * @retval MSG_RESET    if the mailbox has been reset while waiting.
 * @retval MSG_TIMEOUT  if the operation has timed out.
 *
 * @api
 */
msg_t chMBPost(mailbox_t *mbp, msg_t msg, systime_t timeout) {
  msg_t rdymsg;

  chSysLock();
  rdymsg = chMBPostS(mbp, msg, timeout);
  chSysUnlock();

  return rdymsg;
}

/**
 * @brief   Posts a message into a mailbox.
 * @details The invoking thread waits until a empty slot in the mailbox becomes
 *          available or the specified time runs out.
 *
 * @param[in] mbp       the pointer to an initialized @p mailbox_t object
 * @param[in] msg       the message to be posted on the mailbox
 * @param[in] timeout   the number of ticks before the operation timeouts,
 *                      the following special values are allowed:
 *                      - @a TIME_IMMEDIATE immediate timeout.
 *                      - @a TIME_INFINITE no timeout.
 *                      .
 * @return              The operation status.
 * @retval MSG_OK       if a message has been correctly posted.
 * @retval MSG_RESET    if the mailbox has been reset while waiting.
 * @retval MSG_TIMEOUT  if the operation has timed out.
 *
 * @sclass
 */
msg_t chMBPostS(mailbox_t *mbp, msg_t msg, systime_t timeout) {
  msg_t rdymsg;

  chDbgCheckClassS();
  chDbgCheck(mbp != NULL);

  rdymsg = chSemWaitTimeoutS(&mbp->emptysem, timeout);
  if (rdymsg == MSG_OK) {
    *mbp->wrptr++ = msg;
    if (mbp->wrptr >= mbp->top) {
      mbp->wrptr = mbp->buffer;
    }
    chSemSignalI(&mbp->fullsem);
    chSchRescheduleS();
  }

  return rdymsg;
}

/**
 * @brief   Posts a message into a mailbox.
 * @details This variant is non-blocking, the function returns a timeout
 *          condition if the queue is full.
 *
 * @param[in] mbp       the pointer to an initialized @p mailbox_t object
 * @param[in] msg       the message to be posted on the mailbox
 * @return              The operation status.
 * @retval MSG_OK       if a message has been correctly posted.
 * @retval MSG_TIMEOUT  if the mailbox is full and the message cannot be
 *                      posted.
 *
 * @iclass
 */
msg_t chMBPostI(mailbox_t *mbp, msg_t msg) {

  chDbgCheckClassI();
  chDbgCheck(mbp != NULL);

  if (chSemGetCounterI(&mbp->emptysem) <= (cnt_t)0) {
    return MSG_TIMEOUT;
  }

  chSemFastWaitI(&mbp->emptysem);
  *mbp->wrptr++ = msg;
  if (mbp->wrptr >= mbp->top) {
     mbp->wrptr = mbp->buffer;
  }
  chSemSignalI(&mbp->fullsem);

  return MSG_OK;
}

/**
 * @brief   Posts an high priority message into a mailbox.
 * @details The invoking thread waits until a empty slot in the mailbox becomes
 *          available or the specified time runs out.
 *
 * @param[in] mbp       the pointer to an initialized @p mailbox_t object
 * @param[in] msg       the message to be posted on the mailbox
 * @param[in] timeout   the number of ticks before the operation timeouts,
 *                      the following special values are allowed:
 *                      - @a TIME_IMMEDIATE immediate timeout.
 *                      - @a TIME_INFINITE no timeout.
 *                      .
 * @return              The operation status.
 * @retval MSG_OK       if a message has been correctly posted.
 * @retval MSG_RESET    if the mailbox has been reset while waiting.
 * @retval MSG_TIMEOUT  if the operation has timed out.
 *
 * @api
 */
msg_t chMBPostAhead(mailbox_t *mbp, msg_t msg, systime_t timeout) {
  msg_t rdymsg;

  chSysLock();
  rdymsg = chMBPostAheadS(mbp, msg, timeout);
  chSysUnlock();

  return rdymsg;
}

/**
 * @brief   Posts an high priority message into a mailbox.
 * @details The invoking thread waits until a empty slot in the mailbox becomes
 *          available or the specified time runs out.
 *
 * @param[in] mbp       the pointer to an initialized @p mailbox_t object
 * @param[in] msg       the message to be posted on the mailbox
 * @param[in] timeout   the number of ticks before the operation timeouts,
 *                      the following special values are allowed:
 *                      - @a TIME_IMMEDIATE immediate timeout.
 *                      - @a TIME_INFINITE no timeout.
 *                      .
 * @return              The operation status.
 * @retval MSG_OK       if a message has been correctly posted.
 * @retval MSG_RESET    if the mailbox has been reset while waiting.
 * @retval MSG_TIMEOUT  if the operation has timed out.
 *
 * @sclass
 */
msg_t chMBPostAheadS(mailbox_t *mbp, msg_t msg, systime_t timeout) {
  msg_t rdymsg;

  chDbgCheckClassS();
  chDbgCheck(mbp != NULL);

  rdymsg = chSemWaitTimeoutS(&mbp->emptysem, timeout);
  if (rdymsg == MSG_OK) {
    if (--mbp->rdptr < mbp->buffer) {
      mbp->rdptr = mbp->top - 1;
    }
    *mbp->rdptr = msg;
    chSemSignalI(&mbp->fullsem);
    chSchRescheduleS();
  }

  return rdymsg;
}

/**
 * @brief   Posts an high priority message into a mailbox.
 * @details This variant is non-blocking, the function returns a timeout
 *          condition if the queue is full.
 *
 * @param[in] mbp       the pointer to an initialized @p mailbox_t object
 * @param[in] msg       the message to be posted on the mailbox
 * @return              The operation status.
 * @retval MSG_OK       if a message has been correctly posted.
 * @retval MSG_TIMEOUT  if the mailbox is full and the message cannot be
 *                      posted.
 *
 * @iclass
 */
msg_t chMBPostAheadI(mailbox_t *mbp, msg_t msg) {

  chDbgCheckClassI();
  chDbgCheck(mbp != NULL);

  if (chSemGetCounterI(&mbp->emptysem) <= (cnt_t)0) {
    return MSG_TIMEOUT;
  }
  chSemFastWaitI(&mbp->emptysem);
  if (--mbp->rdptr < mbp->buffer) {
    mbp->rdptr = mbp->top - 1;
  }
  *mbp->rdptr = msg;
  chSemSignalI(&mbp->fullsem);

  return MSG_OK;
}

/**
 * @brief   Retrieves a message from a mailbox.
 * @details The invoking thread waits until a message is posted in the mailbox
 *          or the specified time runs out.
 *
 * @param[in] mbp       the pointer to an initialized @p mailbox_t object
 * @param[out] msgp     pointer to a message variable for the received message
 * @param[in] timeout   the number of ticks before the operation timeouts,
 *                      the following special values are allowed:
 *                      - @a TIME_IMMEDIATE immediate timeout.
 *                      - @a TIME_INFINITE no timeout.
 *                      .
 * @return              The operation status.
 * @retval MSG_OK       if a message has been correctly fetched.
 * @retval MSG_RESET    if the mailbox has been reset while waiting.
 * @retval MSG_TIMEOUT  if the operation has timed out.
 *
 * @api
 */
msg_t chMBFetch(mailbox_t *mbp, msg_t *msgp, systime_t timeout) {
  msg_t rdymsg;

  chSysLock();
  rdymsg = chMBFetchS(mbp, msgp, timeout);
  chSysUnlock();

  return rdymsg;
}

/**
 * @brief   Retrieves a message from a mailbox.
 * @details The invoking thread waits until a message is posted in the mailbox
 *          or the specified time runs out.
 *
 * @param[in] mbp       the pointer to an initialized @p mailbox_t object
 * @param[out] msgp     pointer to a message variable for the received message
 * @param[in] timeout   the number of ticks before the operation timeouts,
 *                      the following special values are allowed:
 *                      - @a TIME_IMMEDIATE immediate timeout.
 *                      - @a TIME_INFINITE no timeout.
 *                      .
 * @return              The operation status.
 * @retval MSG_OK       if a message has been correctly fetched.
 * @retval MSG_RESET    if the mailbox has been reset while waiting.
 * @retval MSG_TIMEOUT  if the operation has timed out.
 *
 * @sclass
 */
msg_t chMBFetchS(mailbox_t *mbp, msg_t *msgp, systime_t timeout) {
  msg_t rdymsg;

  chDbgCheckClassS();
  chDbgCheck((mbp != NULL) && (msgp != NULL));

  rdymsg = chSemWaitTimeoutS(&mbp->fullsem, timeout);
  if (rdymsg == MSG_OK) {
    *msgp = *mbp->rdptr++;
    if (mbp->rdptr >= mbp->top) {
      mbp->rdptr = mbp->buffer;
    }
    chSemSignalI(&mbp->emptysem);
    chSchRescheduleS();
  }

  return rdymsg;
}

/**
 * @brief   Retrieves a message from a mailbox.
 * @details This variant is non-blocking, the function returns a timeout
 *          condition if the queue is empty.
 *
 * @param[in] mbp       the pointer to an initialized @p mailbox_t object
 * @param[out] msgp     pointer to a message variable for the received message
 * @return              The operation status.
 * @retval MSG_OK       if a message has been correctly fetched.
 * @retval MSG_TIMEOUT  if the mailbox is empty and a message cannot be
 *                      fetched.
 *
 * @iclass
 */
msg_t chMBFetchI(mailbox_t *mbp, msg_t *msgp) {

  chDbgCheckClassI();
  chDbgCheck((mbp != NULL) && (msgp != NULL));

  if (chSemGetCounterI(&mbp->fullsem) <= (cnt_t)0) {
    return MSG_TIMEOUT;
  }
  chSemFastWaitI(&mbp->fullsem);
  *msgp = *mbp->rdptr++;
  if (mbp->rdptr >= mbp->top) {
    mbp->rdptr = mbp->buffer;
  }
  chSemSignalI(&mbp->emptysem);

  return MSG_OK;
}
#endif /* CH_CFG_USE_MAILBOXES == TRUE */

/** @} */
generated by cgit v1.2.3 (git 2.25.1) at 2025-10-17 17:57:41 +0000