dlt_shm.c

Go to the documentation of this file.

/*
 * @licence app begin@
 * SPDX license identifier: MPL-2.0
 *
 * Copyright (C) 2011-2015, BMW AG
 *
 * This file is part of GENIVI Project DLT - Diagnostic Log and Trace.
 *
 * This Source Code Form is subject to the terms of the
 * Mozilla Public License (MPL), v. 2.0.
 * If a copy of the MPL was not distributed with this file,
 * You can obtain one at http://mozilla.org/MPL/2.0/.
 *
 * For further information see http://www.genivi.org/.
 * @licence end@
 */

/*******************************************************************************
**                                                                            **
**  SRC-MODULE: dlt_shm.c                                                     **
**                                                                            **
**  TARGET    : linux                                                         **
**                                                                            **
**  PROJECT   : DLT                                                           **
**                                                                            **
**  AUTHOR    : Alexander Wenzel Alexander.AW.Wenzel@bmw.de                   **
**                                                                            **
**  PURPOSE   :                                                               **
**                                                                            **
**  REMARKS   :                                                               **
**                                                                            **
**  PLATFORM DEPENDANT [yes/no]: yes                                          **
**                                                                            **
**  TO BE CHANGED BY USER [yes/no]: no                                        **
**                                                                            **
*******************************************************************************/

/*******************************************************************************
**                      Author Identity                                       **
********************************************************************************
**                                                                            **
** Initials     Name                       Company                            **
** --------     -------------------------  ---------------------------------- **
**  aw          Alexander Wenzel           BMW                                **
*******************************************************************************/

#include <sys/types.h>
#include <sys/ipc.h>
#include <sys/shm.h>
#include <sys/sem.h>
#include <sys/stat.h>
#include <stdio.h>
#include <string.h>

#if !defined(_MSC_VER)
#include <unistd.h>
#include <syslog.h>
#endif

#include <dlt_shm.h>
#include <dlt_common.h>

void dlt_shm_print_hex(char *ptr,int size)
{
    int num;

    for (num=0;num<size;num++)
    {
        if((num%16)==15)
            printf("%.2x\n",((unsigned char*)ptr)[num]);
        else
            printf("%.2x ",((unsigned char*)ptr)[num]);
    }
    printf("\n");
}

void dlt_shm_pv(int id,int operation)
{
    static struct sembuf semaphor;

    semaphor.sem_op = operation;
    semaphor.sem_flg = SEM_UNDO;

    if(semop(id, &semaphor,1) == -1) {
        dlt_log(LOG_WARNING,"SHM: semop() failed");
    }
}

int dlt_shm_init_server(DltShm *buf,int key,int size) {
    struct shmid_ds shm_buf;
    unsigned char *ptr;

    // Init parameters
    buf->shmid = 0;
    buf->semid = 0;

    // Create the segment.
    if ((buf->shmid = shmget(key, size, IPC_CREAT | 0666)) < 0) {
        dlt_log(LOG_WARNING,"SHM: shmget() failed");
        return DLT_RETURN_ERROR; /* ERROR */
    }

    // get the size of shm
    if (shmctl(buf->shmid,  IPC_STAT, &shm_buf))
    {
        dlt_log(LOG_WARNING,"SHM: shmctl() failed");
        return DLT_RETURN_ERROR; /* ERROR */
    }

    // Now we attach the segment to our data space.
    if ((ptr = shmat(buf->shmid, NULL, 0)) == (unsigned char *) -1) {
        dlt_log(LOG_WARNING,"SHM: shmat() failed");
        return DLT_RETURN_ERROR; /* ERROR */
    }

    // Init semaphore
    if( (buf->semid = semget(DLT_SHM_SEM,1,S_IRWXU|S_IRWXG|S_IRWXO|IPC_CREAT|IPC_EXCL)) == -1 ) {
        if( (buf->semid = semget(DLT_SHM_SEM,1,S_IRWXU|S_IRWXG|S_IRWXO|IPC_EXCL)) == -1 ) {
            dlt_log(LOG_WARNING,"SHM: semget() failed");
            return DLT_RETURN_ERROR; /* ERROR */
        }
    }
    if( semctl(buf->semid,0,SETVAL,(int)1) == -1 ) {
        dlt_log(LOG_WARNING,"SHM: semctl() failed");
        return DLT_RETURN_ERROR; /* ERROR */
    }

    // init buffer
    dlt_buffer_init_static_server(&(buf->buffer),ptr,shm_buf.shm_segsz);

    return DLT_RETURN_OK; /* OK */
}

DltReturnValue dlt_shm_init_client(DltShm *buf,int key) {
    struct shmid_ds shm_buf;
    unsigned char *ptr;

    // init parameters
    buf->shmid = 0;
    buf->semid = 0;

    // Create the segment.
    if ((buf->shmid = shmget(key, 0, 0666)) < 0) {
        dlt_log(LOG_WARNING,"SHM: shmget() failed");
        return DLT_RETURN_ERROR; /* ERROR */
    }

    // get the size of shm
    if (shmctl(buf->shmid,  IPC_STAT, &shm_buf))
    {
        dlt_log(LOG_WARNING,"SHM: shmctl() failed");
            return DLT_RETURN_ERROR; /* ERROR */
    }

    // Now we attach the segment to our data space.
    if ((ptr = shmat(buf->shmid, NULL, 0)) == (unsigned char *) -1) {
        dlt_log(LOG_WARNING,"shmat() failed");
        return DLT_RETURN_ERROR; /* ERROR */
    }

    // Init semaphore
    if( (buf->semid = semget(DLT_SHM_SEM,0,0)) == -1 ) {
            dlt_log(LOG_WARNING,"SHM: semget() failed");
            return DLT_RETURN_ERROR; /* ERROR */
    }

    // init buffer
    dlt_buffer_init_static_client(&(buf->buffer),ptr,shm_buf.shm_segsz);

    return DLT_RETURN_OK; /* OK */
}

void dlt_shm_info(DltShm *buf)
{
    dlt_buffer_info(&(buf->buffer));
}

void dlt_shm_status(DltShm *buf)
{
    dlt_buffer_status(&(buf->buffer));
}

int dlt_shm_get_total_size(DltShm *buf)
{
    return dlt_buffer_get_total_size(&(buf->buffer));
}

int dlt_shm_get_used_size(DltShm *buf)
{
    int ret;

    /* check if buffer available */
    if(!buf->buffer.mem)
        return -1;

    DLT_SHM_SEM_GET(buf->semid);
    ret =  dlt_buffer_get_used_size(&(buf->buffer));
    DLT_SHM_SEM_FREE(buf->semid);

    return ret;
}

int dlt_shm_get_message_count(DltShm *buf)
{
    return dlt_buffer_get_message_count(&(buf->buffer));
}

int dlt_shm_push(DltShm *buf,const unsigned char *data1,unsigned int size1,const unsigned char *data2,unsigned int size2,const unsigned char *data3,unsigned int size3)
{
    int ret;

    /* check if buffer available */
    if(!buf->buffer.mem)
        return -1;

    DLT_SHM_SEM_GET(buf->semid);
    ret =  dlt_buffer_push3(&(buf->buffer),data1,size1,data2,size2,data3,size3);
    DLT_SHM_SEM_FREE(buf->semid);

    return ret;
}

int dlt_shm_pull(DltShm *buf,unsigned char *data, int max_size)
{
    int ret;

    /* check if buffer available */
    if(!buf->buffer.mem)
        return -1;

    DLT_SHM_SEM_GET(buf->semid);
    ret =  dlt_buffer_pull(&(buf->buffer),data,max_size);
    DLT_SHM_SEM_FREE(buf->semid);

    return ret;
}

int dlt_shm_copy(DltShm *buf,unsigned char *data, int max_size)
{
    int ret;

    /* check if buffer available */
    if(!buf->buffer.mem)
        return -1;

    DLT_SHM_SEM_GET(buf->semid);
    ret =  dlt_buffer_copy(&(buf->buffer),data,max_size);
    DLT_SHM_SEM_FREE(buf->semid);

    return ret;
}

int dlt_shm_remove(DltShm *buf)
{
    int ret;

    /* check if buffer available */
    if(!buf->buffer.mem)
        return -1;

    DLT_SHM_SEM_GET(buf->semid);
    ret =  dlt_buffer_remove(&(buf->buffer));
    DLT_SHM_SEM_FREE(buf->semid);

    return ret;
}

DltReturnValue dlt_shm_free_server(DltShm *buf) {

    if(shmdt(buf->buffer.shm)) {
        dlt_log(LOG_WARNING,"SHM: shmdt() failed");
        return DLT_RETURN_ERROR; /* ERROR */
    }

    if(shmctl(buf->shmid,IPC_RMID,NULL) == -1) {
        dlt_log(LOG_WARNING,"SHM: shmdt() failed");
        return DLT_RETURN_ERROR; /* ERROR */
    }

    if(semctl(buf->semid,0,IPC_RMID,(int)0) == -1) {
        dlt_log(LOG_WARNING,"SHM: shmdt() failed");
        return DLT_RETURN_ERROR; /* ERROR */
    }

    // Reset parameters
    buf->shmid = 0;
    buf->semid = 0;

    return dlt_buffer_free_static(&(buf->buffer));

}

DltReturnValue dlt_shm_free_client(DltShm *buf) {

    if(shmdt(buf->buffer.shm)) {
        dlt_log(LOG_WARNING,"SHM: shmdt() failed");
        return DLT_RETURN_ERROR; /* ERROR */
    }

    // Reset parameters
    buf->shmid = 0;
    buf->semid = 0;

    return dlt_buffer_free_static(&(buf->buffer));
}