/*

* Copyright (c) 2006-2009 Nokia Corporation and/or its subsidiary(-ies).

* All rights reserved.

* This component and the accompanying materials are made available

* under the terms of "Eclipse Public License v1.0"

* which accompanies this distribution, and is available

* at the URL "http://www.eclipse.org/legal/epl-v10.html".

*

* Initial Contributors:

* Nokia Corporation - initial contribution.

*

* Contributors:

*

* Description:  Implementation of shared memory (POSIX Standard).

*

*/

// INCLUDE FILES

#include <errno.h>

#include <sys/ipc.h>

#include <sys/shm.h>

#include <unistd.h>

#include "sysreent.h"

// -----------------------------------------------------------------------------

// Funcation name: shmget

// Description: Get shared memory identifier using the IPC key generated by ftok.

// Returns: None zero number (shared memory identifier): On success

//          -1              : On error.

// In case of error, errno value set to

//          EACCES - Operation permission is denied to the calling process, see IPC.

//          EINVAL - The value of semid is not a valid semaphore identifier, or the

//                   value of semnum is less than 0 or greater than or equal to

//                   sem_nsems, or the value of cmd is not a valid command.

//          EPERM -  The argument cmd is equal to IPC_RMID or IPC_SET and the effective

//                   user ID of the calling process is not equal to that of a process

//                   with appropriate privileges and it is not equal to the value of

//                   sem_perm.cuid or sem_perm.uid in the data structure associated

//                   with semid.

//          ERANGE - The argument cmd is equal to SETVAL or SETALL and the value to

//                   which semval is to be set is greater than the system-imposed

//                   maximum.

// -----------------------------------------------------------------------------

//

extern "C" {

EXPORT_C int shmget(key_t key, int size, int shmflg)

    {

        return _shmget_r(&errno, key, size, shmflg);

    }

// -----------------------------------------------------------------------------

// Funcation name: shmat

// Description: Attaches the shared memory segment associated with the shared

//              memory identifier specified by shmid to the address space of

//              the calling process.

// Returns: Segment's start address: On success

//          -1   : On error.

// In case of error, errno value set to

//          EACCES - Operation permission is denied to the calling process.

//          EINVAL - The value of shmid is not a valid shared memory identifier;

//                   the shmaddr is not a null pointer and the value of

//                   (shmaddr-((ptrdiff_t)shmaddr%SHMLBA)) is an illegal

//                   address for attaching shared memory; or the shmaddr is not

//                   a null pointer, (shmflg&SHM_RND) is 0 and the value of

//                   shmaddr is an illegal address for attaching shared memory.

//          EMFILE - The number of shared memory segments attached to the calling

//                   process would exceed the system-imposed limit.

//          ENOMEM - The available data space is not large enough to accommodate

//                   the shared memory segment.

// -----------------------------------------------------------------------------

//

EXPORT_C void* shmat(int shmid, const void *shmaddr, int shmflg)

    {

    return _shmat_r(&errno, shmid, shmaddr, shmflg);

    }

// -----------------------------------------------------------------------------

// Funcation name: shmdt

// Description: Detaches the shared memory segment located at the address

//              specified by shmaddr from the address space of the calling process.

// Returns: 0    : On success.

//          -1   : On error.

// In case of error, errno value set to

//          EINVAL - The value of shmaddr is not the data segment start

//                   address of a shared memory segment.

// -----------------------------------------------------------------------------

//

EXPORT_C int shmdt(const void *shmaddr)

    {

    return _shmdt_r(&errno, shmaddr);

    }

// -----------------------------------------------------------------------------

// Funcation name: shmctl

// Description: Provides a variety of shared memory control operations as

//              specified by cmd.

// Returns: 0  : On success

//          -1 : On error.

// In case of error, errno value set to

//          EACCES - The argument cmd is equal to IPC_STAT and the calling

//                   process does not have read permission.

//          EINVAL- The value of shmid is not a valid shared memory

//                   identifier, or the value of cmd is not a valid command.

//          EPERM - The argument cmd is equal to IPC_RMID or IPC_SET and the

//                  effective user ID of the calling process is not equal to

//                  that of a process with appropriate privileges and it is

//                  not equal to the value of shm_perm.cuid or shm_perm.uid

//                  in the data structure associated with shmid.

//          EOVERFLO - The cmd argument is IPC_STAT and the gid or uid value

//                     is too large to be stored in the structure pointed to

//                     by the buf argument

// -----------------------------------------------------------------------------

//

EXPORT_C int shmctl(int shmid, int cmd, struct shmid_ds *buf)

    {

    return _shmctl_r(&errno, shmid, cmd, buf);

    }

} // extern "C" {

//  End of File