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Diffstat (limited to 'os/oslib/include/chpipes.h')
| -rw-r--r-- | os/oslib/include/chpipes.h | 208 |
1 files changed, 208 insertions, 0 deletions
diff --git a/os/oslib/include/chpipes.h b/os/oslib/include/chpipes.h new file mode 100644 index 000000000..8bf26c62b --- /dev/null +++ b/os/oslib/include/chpipes.h @@ -0,0 +1,208 @@ +/* + ChibiOS - Copyright (C) 2006..2018 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 chpipes.h + * @brief Pipes macros and structures. + * + * @addtogroup oslib_pipes + * @{ + */ + +#ifndef CHPIPES_H +#define CHPIPES_H + +#if (CH_CFG_USE_PIPES == TRUE) || defined(__DOXYGEN__) + +/*===========================================================================*/ +/* Module constants. */ +/*===========================================================================*/ + +/*===========================================================================*/ +/* Module pre-compile time settings. */ +/*===========================================================================*/ + +/*===========================================================================*/ +/* Derived constants and error checks. */ +/*===========================================================================*/ + +/*===========================================================================*/ +/* Module data structures and types. */ +/*===========================================================================*/ + +/** + * @brief Structure representing a pipe object. + */ +typedef struct { + uint8_t *buffer; /**< @brief Pointer to the pipe + buffer. */ + uint8_t *top; /**< @brief Pointer to the location + after the buffer. */ + uint8_t *wrptr; /**< @brief Write pointer. */ + uint8_t *rdptr; /**< @brief Read pointer. */ + size_t cnt; /**< @brief Bytes in the pipe. */ + bool reset; /**< @brief True if in reset state. */ + thread_reference_t wtr; /**< @brief Waiting writer. */ + thread_reference_t rtr; /**< @brief Waiting reader. */ +#if (CH_CFG_USE_MUTEXES == TRUE) || defined(__DOXYGEN__) + mutex_t cmtx; /**< @brief Common access mutex. */ + mutex_t wmtx; /**< @brief Write access mutex. */ + mutex_t rmtx; /**< @brief Read access mutex. */ +#else + semaphore_t csem; /**< @brief Common access semaphore.*/ + semaphore_t wsem; /**< @brief Write access semaphore. */ + semaphore_t rsem; /**< @brief Read access semaphore. */ +#endif +} pipe_t; + +/*===========================================================================*/ +/* Module macros. */ +/*===========================================================================*/ + +/** + * @brief Data part of a static pipe initializer. + * @details This macro should be used when statically initializing a + * pipe that is part of a bigger structure. + * + * @param[in] name the name of the pipe variable + * @param[in] buffer pointer to the pipe buffer array of @p uint8_t + * @param[in] size number of @p uint8_t elements in the buffer array + */ +#if (CH_CFG_USE_MUTEXES == TRUE) || defined(__DOXYGEN__) +#define _PIPE_DATA(name, buffer, size) { \ + (uint8_t *)(buffer), \ + (uint8_t *)(buffer) + size, \ + (uint8_t *)(buffer), \ + (uint8_t *)(buffer), \ + (size_t)0, \ + false, \ + NULL, \ + NULL, \ + _MUTEX_DATA(name.cmtx), \ + _MUTEX_DATA(name.wmtx), \ + _MUTEX_DATA(name.rmtx), \ +} +#else /* CH_CFG_USE_MUTEXES == FALSE */ +#define _PIPE_DATA(name, buffer, size) { \ + (uint8_t *)(buffer), \ + (uint8_t *)(buffer) + size, \ + (uint8_t *)(buffer), \ + (uint8_t *)(buffer), \ + (size_t)0, \ + false, \ + NULL, \ + NULL, \ + _SEMAPHORE_DATA(name.csem, (cnt_t)1), \ + _SEMAPHORE_DATA(name.wsem, (cnt_t)1), \ + _SEMAPHORE_DATA(name.rsem, (cnt_t)1), \ +} +#endif /* CH_CFG_USE_MUTEXES == FALSE */ + +/** + * @brief Static pipe initializer. + * @details Statically initialized pipes require no explicit + * initialization using @p chPipeObjectInit(). + * + * @param[in] name the name of the pipe variable + * @param[in] buffer pointer to the pipe buffer array of @p uint8_t + * @param[in] size number of @p uint8_t elements in the buffer array + */ +#define PIPE_DECL(name, buffer, size) \ + pipe_t name = _PIPE_DATA(name, buffer, size) + +/*===========================================================================*/ +/* External declarations. */ +/*===========================================================================*/ + +#ifdef __cplusplus +extern "C" { +#endif + void chPipeObjectInit(pipe_t *pp, uint8_t *buf, size_t n); + void chPipeReset(pipe_t *pp); + size_t chPipeWriteTimeout(pipe_t *pp, const uint8_t *bp, + size_t n, sysinterval_t timeout); + size_t chPipeReadTimeout(pipe_t *pp, uint8_t *bp, + size_t n, sysinterval_t timeout); +#ifdef __cplusplus +} +#endif + +/*===========================================================================*/ +/* Module inline functions. */ +/*===========================================================================*/ + +/** + * @brief Returns the pipe buffer size as number of bytes. + * + * @param[in] pp the pointer to an initialized @p pipe_t object + * @return The size of the pipe. + * + * @api + */ +static inline size_t chPipeGetSize(const pipe_t *pp) { + + /*lint -save -e9033 [10.8] Perfectly safe pointers + arithmetic.*/ + return (size_t)(pp->top - pp->buffer); + /*lint -restore*/ +} + +/** + * @brief Returns the number of used byte slots into a pipe. + * + * @param[in] pp the pointer to an initialized @p pipe_t object + * @return The number of queued bytes. + * + * @api + */ +static inline size_t chPipeGetUsedCount(const pipe_t *pp) { + + return pp->cnt; +} + +/** + * @brief Returns the number of free byte slots into a pipe. + * + * @param[in] pp the pointer to an initialized @p pipe_t object + * @return The number of empty byte slots. + * + * @api + */ +static inline size_t chPipeGetFreeCount(const pipe_t *pp) { + + return chPipeGetSize(pp) - chPipeGetUsedCount(pp); +} + +/** + * @brief Terminates the reset state. + * + * @param[in] pp the pointer to an initialized @p pipe_t object + * + * @api + */ +static inline void chPipeResume(pipe_t *pp) { + + pp->reset = false; +} + +#endif /* CH_CFG_USE_PIPES == TRUE */ + +#endif /* CHPIPES_H */ + +/** @} */ |