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author | Joel Sherrill <joel.sherrill@OARcorp.com> | 1999-11-02 21:48:15 +0000 |
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committer | Joel Sherrill <joel.sherrill@OARcorp.com> | 1999-11-02 21:48:15 +0000 |
commit | 7cc8d6c3b1a207684892d207055ceff9f37d5731 (patch) | |
tree | 3da2f9ee0425a6b49a32df5c8298789de0672add /c/src/exec/score/src/coresemseize.c | |
parent | Split core message queue and watchdog handler objects into separate files. (diff) | |
download | rtems-7cc8d6c3b1a207684892d207055ceff9f37d5731.tar.bz2 |
Split core mutex and semaphore handlers into separate files.
Diffstat (limited to '')
-rw-r--r-- | c/src/exec/score/src/coresemseize.c | 81 |
1 files changed, 81 insertions, 0 deletions
diff --git a/c/src/exec/score/src/coresemseize.c b/c/src/exec/score/src/coresemseize.c new file mode 100644 index 0000000000..f08b40ca5b --- /dev/null +++ b/c/src/exec/score/src/coresemseize.c @@ -0,0 +1,81 @@ +/* + * CORE Semaphore Handler + * + * DESCRIPTION: + * + * This package is the implementation of the CORE Semaphore Handler. + * This core object utilizes standard Dijkstra counting semaphores to provide + * synchronization and mutual exclusion capabilities. + * + * COPYRIGHT (c) 1989-1998. + * On-Line Applications Research Corporation (OAR). + * Copyright assigned to U.S. Government, 1994. + * + * The license and distribution terms for this file may be + * found in the file LICENSE in this distribution or at + * http://www.OARcorp.com/rtems/license.html. + * + * $Id$ + */ + +#include <rtems/system.h> +#include <rtems/score/isr.h> +#include <rtems/score/coresem.h> +#include <rtems/score/states.h> +#include <rtems/score/thread.h> +#include <rtems/score/threadq.h> +#if defined(RTEMS_MULTIPROCESSING) +#include <rtems/score/mpci.h> +#endif + +/*PAGE + * + * _CORE_semaphore_Seize + * + * This routine attempts to allocate a core semaphore to the calling thread. + * + * Input parameters: + * the_semaphore - pointer to semaphore control block + * id - id of object to wait on + * wait - TRUE if wait is allowed, FALSE otherwise + * timeout - number of ticks to wait (0 means forever) + * + * Output parameters: NONE + * + * INTERRUPT LATENCY: + * available + * wait + */ + +void _CORE_semaphore_Seize( + CORE_semaphore_Control *the_semaphore, + Objects_Id id, + boolean wait, + Watchdog_Interval timeout +) +{ + Thread_Control *executing; + ISR_Level level; + + executing = _Thread_Executing; + executing->Wait.return_code = CORE_SEMAPHORE_STATUS_SUCCESSFUL; + _ISR_Disable( level ); + if ( the_semaphore->count != 0 ) { + the_semaphore->count -= 1; + _ISR_Enable( level ); + return; + } + + if ( !wait ) { + _ISR_Enable( level ); + executing->Wait.return_code = CORE_SEMAPHORE_STATUS_UNSATISFIED_NOWAIT; + return; + } + + _Thread_queue_Enter_critical_section( &the_semaphore->Wait_queue ); + executing->Wait.queue = &the_semaphore->Wait_queue; + executing->Wait.id = id; + _ISR_Enable( level ); + + _Thread_queue_Enqueue( &the_semaphore->Wait_queue, timeout ); +} |