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Diffstat (limited to 'cpukit/include/mqueue.h')
| -rw-r--r-- | cpukit/include/mqueue.h | 218 |
1 files changed, 218 insertions, 0 deletions
diff --git a/cpukit/include/mqueue.h b/cpukit/include/mqueue.h new file mode 100644 index 0000000000..36733a4730 --- /dev/null +++ b/cpukit/include/mqueue.h @@ -0,0 +1,218 @@ +/** + * @file + * + * @brief POSIX Message Queues + * + * This file contains the definitions related to POSIX Message Queues. + * + * The structure of the routines is identical to that of POSIX + * Message_queues to leave the option of having unnamed message + * queues at a future date. They are currently not part of the + * POSIX standard but unnamed message_queues are. This is also + * the reason for the apparently unnecessary tracking of + * the process_shared attribute. [In addition to the fact that + * it would be trivial to add pshared to the mq_attr structure + * and have process private message queues.] + * + * This code ignores the O_RDONLY/O_WRONLY/O_RDWR flag at open + * time. + */ + +/* + * COPYRIGHT (c) 1989-2011. + * On-Line Applications Research Corporation (OAR). + * + * The license and distribution terms for this file may be + * found in the file LICENSE in this distribution or at + * http://www.rtems.org/license/LICENSE. + */ + +#ifndef _MQUEUE_H +#define _MQUEUE_H + + +#include <unistd.h> + +#if defined(_POSIX_MESSAGE_PASSING) + +#include <sys/types.h> + +#include <rtems/system.h> +#include <rtems/score/object.h> + +/** + * @defgroup POSIX_MQUEUE POSIX Message Queues + * + * @ingroup POSIXAPI + * + */ +/**@{**/ + +#ifdef __cplusplus +extern "C" { +#endif + +/* + * 15.1.1 Data Structures, P1003.1b-1993, p. 271 + */ + +/** + * Message queue id type. + * + * NOTE: Use uint32_t since all POSIX Ids are 32-bit currently. + */ +typedef uint32_t mqd_t; + +/** + * This is the message queue attributes structure. + */ +struct mq_attr { + /** This is the message queue flags */ + long mq_flags; + /** This is the maximum number of messages */ + long mq_maxmsg; + /** This is the maximum message size */ + long mq_msgsize; + /** This is the mumber of messages currently queued */ + long mq_curmsgs; +}; + +/** + * 15.2.2 Open a Message Queue, P1003.1b-1993, p. 272 + */ +mqd_t mq_open( + const char *name, + int oflag, + ... +); + +/** + * 15.2.2 Close a Message Queue, P1003.1b-1993, p. 275 + */ +int mq_close( + mqd_t mqdes +); + +/** + * @brief Remove a message queue. + * + * 15.2.2 Remove a Message Queue, P1003.1b-1993, p. 276 + * + * NOTE: The structure of the routines is identical to that of POSIX + * Message_queues to leave the option of having unnamed message + * queues at a future date. They are currently not part of the + * POSIX standard but unnamed message_queues are. This is also + * the reason for the apparently unnecessary tracking of + * the process_shared attribute. [In addition to the fact that + * it would be trivial to add pshared to the mq_attr structure + * and have process private message queues.] + * + * This code ignores the O_RDONLY/O_WRONLY/O_RDWR flag at open + * time. + */ +int mq_unlink( + const char *name +); + +/** + * 15.2.4 Send a Message to a Message Queue, P1003.1b-1993, p. 277 + * + * NOTE; P1003.4b/D8, p. 45 adds mq_timedsend(). + */ +int mq_send( + mqd_t mqdes, + const char *msg_ptr, + size_t msg_len, + unsigned int msg_prio +); + +#if defined(_POSIX_TIMEOUTS) + +#include <time.h> + +/** + * @brief Send a message to a message queue. + * + * @see mq_send() + */ +int mq_timedsend( + mqd_t mqdes, + const char *msg_ptr, + size_t msg_len, + unsigned int msg_prio, + const struct timespec *abstime +); + +#endif /* _POSIX_TIMEOUTS */ + +/** + * @brief Receive a message from a message queue. + * + * 15.2.5 Receive a Message From a Message Queue, P1003.1b-1993, p. 279 + * + * NOTE: P1003.4b/D8, p. 45 adds mq_timedreceive(). + */ +ssize_t mq_receive( + mqd_t mqdes, + char *msg_ptr, + size_t msg_len, + unsigned int *msg_prio +); + +#if defined(_POSIX_TIMEOUTS) + +ssize_t mq_timedreceive( + mqd_t mqdes, + char *__restrict msg_ptr, + size_t msg_len, + unsigned int *__restrict msg_prio, + const struct timespec *__restrict abstime +); + +#endif /* _POSIX_TIMEOUTS */ + +#if defined(_POSIX_REALTIME_SIGNALS) + +/** + * @brief Notify process that a message is available on a queue. + * + * 15.2.6 Notify Process that a Message is Available on a Queue, + * P1003.1b-1993, p. 280 + */ +int mq_notify( + mqd_t mqdes, + const struct sigevent *notification +); + +#endif /* _POSIX_REALTIME_SIGNALS */ + +/** + * @brief Set message queue attributes. + * + * 15.2.7 Set Message Queue Attributes, P1003.1b-1993, p. 281 + */ +int mq_setattr( + mqd_t mqdes, + const struct mq_attr *__restrict mqstat, + struct mq_attr *__restrict omqstat +); + +/* + * 15.2.8 Get Message Queue Attributes, P1003.1b-1993, p. 283 + */ + +int mq_getattr( + mqd_t mqdes, + struct mq_attr *mqstat +); + +/** @} */ + +#ifdef __cplusplus +} +#endif + +#endif /* _POSIX_MESSAGE_PASSING */ + +#endif +/* end of include file */ |