git-svn-id: svn://svn.code.sf.net/p/chibios/svn/trunk@2036 35acf78f-673a-0410-8e92-d51de3d6d3f4

4 files changed, 229 insertions, 6 deletions

diff --git a/os/kernel/include/chbsem.h b/os/kernel/include/chbsem.h
new file mode 100644
index 000000000..b8cd08306
--- /dev/null
+++ b/os/kernel/include/chbsem.h
@@ -0,0 +1,218 @@
+/*

+    ChibiOS/RT - Copyright (C) 2006,2007,2008,2009,2010 Giovanni Di Sirio.

+

+    This file is part of ChibiOS/RT.

+

+    ChibiOS/RT 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/RT 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    chbsem.h

+ * @brief   Binary semaphores structures and macros.

+ *

+ * @addtogroup binary_semaphores

+ * @details Binary semaphores related APIs and services.

+ *

+ *          <h2>Operation mode</h2>

+ *          Binary semaphores are implemented as a set of macros that use the

+ *          existing counting semaphores primitives. The difference between

+ *          counting and binary semaphores is that the counter of binary

+ *          semaphores is not allowed to grow above the value 1. Repeated

+ *          signal operation are ignored. A binary semaphore can thus have

+ *          only two defined states:

+ *          - <b>Taken</b>, when its counter has a value of zero or lower

+ *            than zero. A negative number represent the number of threads

+ *            queued on the binary semaphore.

+ *          - <b>Not taken</b>, when its counter has a value of one.

+ *          .

+ *          Binary semaphores are different from mutexes because there is no

+ *          the concept of ownership, a binary semaphore can be taken by a

+ *          thread and signaled by another thread or an interrupt handler,

+ *          mutexes can only be taken and released by the same thread. Another

+ *          difference is that binary semaphores, unlike mutexes, do not

+ *          implement the priority inheritance protocol.<br>

+ *          In order to use the binary semaphores APIs the @p CH_USE_SEMAPHORES

+ *          option must be enabled in @p chconf.h.

+ * @{

+ */

+

+#ifndef _CHBSEM_H_

+#define _CHBSEM_H_

+

+#if CH_USE_SEMAPHORES

+

+/**

+ * @extends Semaphore

+ *

+ * @brief   Binary semaphore type.
+ */

+typedef struct  {

+  Semaphore             bs_sem;

+} BinarySemaphore;

+

+/**

+ * @brief   Data part of a static semaphore initializer.

+ * @details This macro should be used when statically initializing a semaphore

+ *          that is part of a bigger structure.

+ *

+ * @param[in] name      the name of the semaphore variable

+ * @param[in] n         the counter initial value, this value must be

+ *                      non-negative

+ */

+#define _BSEMAPHORE_DATA(name, t) {_SEMAPHORE_DATA(name.bs_sem), ((t) ? 0 : 1)}

+

+/**

+ * @brief   Static semaphore initializer.

+ * @details Statically initialized semaphores require no explicit

+ *          initialization using @p chSemInit().

+ *

+ * @param[in] name      the name of the semaphore variable

+ * @param[in] n         the counter initial value, this value must be

+ *                      non-negative

+ */

+#define BSEMAPHORE_DECL(name, t) Semaphore name = _BSEMAPHORE_DATA(name, t)

+

+

+/**

+ * @brief   Initializes a binary semaphore.

+ *

+ * @param[out] bsp      pointer to a @p BinarySemaphore structure

+ * @param[in] taken     initial state of the binary semaphore:

+ *                      - @a FALSE, the initial state is not taken.

+ *                      - @a TRUE, the initial state is taken.

+ *                      .

+ */

+#define chBSemInit(bsp, taken) chSemInit(&bsp->bs_sem, taken ? 0 : 1)

+

+/**

+ * @brief   Wait operation on the binary semaphore.

+ *

+ * @param[in] bsp       pointer to a @p BinarySemaphore structure
+ * @retval RDY_OK       if the binary semaphore had been successfully taken.

+ * @retval RDY_RESET    if the binary semaphore has been reset using

+ *                      @p bsemReset().

+ */

+#define chBSemWait(bsp) chSemWait(&bsp->bs_sem)

+

+/**

+ * @brief   Wait operation on the binary semaphore.

+ *

+ * @param[in] bsp       pointer to a @p BinarySemaphore structure

+ * @retval RDY_OK       if the binary semaphore had been successfully taken.

+ * @retval RDY_RESET    if the binary semaphore has been reset using

+ *                      @p bsemReset().

+ */

+#define chBSemWaitS(bsp) chSemWaitS(&bsp->bs_sem)

+

+/**

+ * @brief   Wait operation on the binary semaphore.

+ *

+ * @param[in] bsp       pointer to a @p BinarySemaphore structure

+ * @param[in] time      the number of ticks before the operation timeouts,

+ *                      the following special values are allowed:

+ *                      - @a TIME_IMMEDIATE immediate timeout.

+ *                      - @a TIME_INFINITE no timeout.

+ *                      .

+ * @retval RDY_OK       if the binary semaphore had been successfully taken.

+ * @retval RDY_RESET    if the binary semaphore has been reset using

+ *                      @p bsemReset().

+ * @retval RDY_TIMEOUT  if the binary semaphore was not signaled or reset

+ *                      within the specified timeout.

+ */

+#define chBSemWaitTimeout(bsp, time) chSemWaitTimeout(&bsp->bs_sem, time)

+

+/**

+ * @brief   Wait operation on the binary semaphore.

+ *

+ * @param[in] bsp       pointer to a @p BinarySemaphore structure

+ * @param[in] time      the number of ticks before the operation timeouts,

+ *                      the following special values are allowed:

+ *                      - @a TIME_IMMEDIATE immediate timeout.

+ *                      - @a TIME_INFINITE no timeout.

+ *                      .

+ * @retval RDY_OK       if the binary semaphore had been successfully taken.

+ * @retval RDY_RESET    if the binary semaphore has been reset using

+ *                      @p bsemReset().

+ * @retval RDY_TIMEOUT  if the binary semaphore was not signaled or reset

+ *                      within the specified timeout.

+ */

+#define chBSemWaitTimeoutS(bsp, time) chSemWaitTimeoutS(&bsp->bs_sem, time)

+

+/**

+ * @brief   Reset operation on the binary semaphore.

+ * @note    The released threads can recognize they were waked up by a reset

+ *          rather than a signal because the @p bsemWait() will return

+ *          @p RDY_RESET instead of @p RDY_OK.

+ *

+ * @param[in] bsp       pointer to a @p BinarySemaphore structure

+ * @param[in] taken     new state of the binary semaphore

+ *                      - @a FALSE, the new state is not taken.

+ *                      - @a TRUE, the new state is taken.

+ *                      .

+ */

+#define chBSemReset(bsp, taken) chSemReset(&bsp->bs_sem, taken ? 0 : 1)

+

+/**

+ * @brief   Reset operation on the binary semaphore.

+ * @note    The released threads can recognize they were waked up by a reset

+ *          rather than a signal because the @p bsemWait() will return

+ *          @p RDY_RESET instead of @p RDY_OK.

+ * @note    This function does not reschedule.

+ *

+ * @param[in] bsp       pointer to a @p BinarySemaphore structure

+ * @param[in] taken     new state of the binary semaphore

+ *                      - @a FALSE, the new state is not taken.

+ *                      - @a TRUE, the new state is taken.

+ *                      .

+ */

+#define chBSemResetI(bsp, taken) chSemResetI(&bsp->bs_sem, taken ? 0 : 1)

+

+/**

+ * @brief   Performs a signal operation on a binary semaphore.

+ *

+ * @param[in] bsp       pointer to a @p BinarySemaphore structure

+ */

+#define chBSemSignal(bsp) {                                                 \

+  chSysLock();                                                              \

+  chBSemSignalI(bsp);                                                       \

+  chSchRescheduleS();                                                       \

+  chSysUnlock();                                                            \

+}

+

+/**

+ * @brief   Performs a signal operation on a binary semaphore.

+ * @note    This function does not reschedule.

+ *

+ * @param[in] bsp       pointer to a @p BinarySemaphore structure

+ */

+#define chBSemSignalI(bsp) {                                                \

+  if (bsp->bs_sem.s_cnt < 1)                                                \

+    chSemSignalI(&bsp->bs_sem);                                             \

+}

+

+/**

+ * @brief   Returns the binary semaphore current state.

+ *

+ * @param[in] bsp       pointer to a @p BinarySemaphore structure

+ * @return              The binary semaphore current state.

+ * @retval FALSE        if the binary semaphore is not taken.

+ * @retval TRUE         if the binary semaphore is taken.

+ */

+#define chBSemGetStateI(bsp) ((bsp)->bs_sem.s_cnt > 0 ? 0 : 1)

+

+#endif /* CH_USE_SEMAPHORES */

+

+#endif /* _CHBSEM_H_ */

+

+/** @} */

diff --git a/os/kernel/kernel.dox b/os/kernel/kernel.dox
index 0cbcd17af..d4206c882 100644
--- a/os/kernel/kernel.dox
+++ b/os/kernel/kernel.dox
@@ -72,7 +72,12 @@
  */

 

 /**

- * @defgroup semaphores Semaphores

+ * @defgroup semaphores Counting Semaphores

+ * @ingroup synchronization

+ */

+

+/**

+ * @defgroup binary_semaphores Binary Semaphores

  * @ingroup synchronization

  */

 

diff --git a/os/kernel/src/chcond.c b/os/kernel/src/chcond.c
index c450b0c32..92e1a4eb4 100644
--- a/os/kernel/src/chcond.c
+++ b/os/kernel/src/chcond.c
@@ -17,8 +17,7 @@
     along with this program.  If not, see <http://www.gnu.org/licenses/>.

 */

 /*

-   Concepts and parts of this file are contributed by and Copyright (C) 2008

-   of Leon Woestenberg.

+   Concepts and parts of this file have been contributed by Leon Woestenberg.

  */

 

 /**

diff --git a/os/kernel/src/chqueues.c b/os/kernel/src/chqueues.c
index 84cbbed94..d1aa03cc6 100644
--- a/os/kernel/src/chqueues.c
+++ b/os/kernel/src/chqueues.c
@@ -126,6 +126,10 @@ msg_t chIQGetTimeout(InputQueue *iqp, systime_t time) {
   msg_t msg;

 

   chSysLock();

+  

+  if (iqp->q_notify)

+    iqp->q_notify();

+

   if ((msg = chSemWaitTimeoutS(&iqp->q_sem, time)) < RDY_OK) {

     chSysUnlock();

     return msg;

@@ -134,9 +138,6 @@ msg_t chIQGetTimeout(InputQueue *iqp, systime_t time) {
   if (iqp->q_rdptr >= iqp->q_top)

     iqp->q_rdptr = iqp->q_buffer;

 

-  if (iqp->q_notify)

-    iqp->q_notify();

-

   chSysUnlock();

   return b;

 }