ap/app/shm_test/shm_read.c

#include <errno.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <unistd.h>
#include <signal.h>
#include <time.h>
#include <pthread.h>
#include <sys/prctl.h>
#include <sys/ipc.h>
#include <sys/shm.h>
#include <sys/types.h>
#include <unistd.h>
#include <assert.h>
#include <sys/mman.h>
#include <sys/stat.h>
#include <fcntl.h>

/**
 * ºê¶¨Òå
 */
#define SHM_TEXT_SIZE             (8192)
#define SHM_PAGE_SIZE             (4096)
#define SHM_ALLOC_ONE_PAGE_SIZE   (1024)
#define SHM_ALLOC_TWO_PAGE_SIZE   (8100)
#define SHM_ALLOC_FOUR_PAGE_SIZE  (16000)

typedef struct 
{
    key_t        key;
    int          shmid;
    unsigned int shm_size;
}shm_node_t;

typedef struct 
{
    int  write;
    char data[SHM_TEXT_SIZE];
}shm_use_remote;

shm_node_t shm_node;

int main (int argc, char *argv[])
{
    int          opt;
    int          ret        = 0;
    int          shmid      = 0;
    unsigned int shm_size   = 0;
    key_t        key        = 0;
    char         *pshm      = NULL;
    char         *read_data = NULL;
    extern char  *optarg;

    shm_use_remote *shared;

    while ((opt = getopt(argc,argv,"k:d:s::")) != EOF)
    {
        switch (opt) 
        {
            case 'k':
                key = atoi(optarg);
                break;
            case 'd':
                read_data = optarg;
                break;
            case 's':
                shm_size = atoi(optarg);
                break;
            default:
                break;
        }
    }

    if (key == 0 || !read_data)
    {
        printf("param error: you can input \"shm_read -k -200 -d \"123456\" -s1024 \n");    
        printf("or \"shm_read -k -200 -d \"123456\" \n");    
        printf("-k -200: create a shm using key -200\n");
        printf("-d \"123456\": if we write 123456 to shm, then can read 123456 form shm, the test case is pass! \n");
        printf("-s1024: set the size of shm, then the default size is 1024 \n");
        return -1;
    }

    if (shm_size == 0)
        shm_size = SHM_ALLOC_ONE_PAGE_SIZE;

    printf("AP read test: key is %d, shm_size is %d\n", key, shm_size);

    shmid = shmget(key, shm_size, 0666|IPC_CREAT);
    if(shmid < 0)
    {
        printf("shmid return error\n");
        return -1;
    }

    pshm = (char *)shmat(shmid, 0, 0);
    if (pshm == NULL)
    {
        printf("shmat return error\n");
        return -1;
    }
    shm_node.key       = key;
    shm_node.shm_size = shm_size;

    shared = (shm_use_remote *)pshm;
    shared->write  = 1;

    while(1)
    {
        if(strncmp(shared->data, read_data, sizeof(read_data)) == 0)
        {
            printf("Success, AP read %s from shm\n", read_data);
            break;
        }
        else
            sleep(2);
    }

    if(shmdt(pshm) < 0)
    {
        printf("shmdt errno %d: %s\n", errno, strerror(errno));
        return -1;
    }

    if(shmctl(shmid, IPC_RMID, NULL) == -1)
    {
        printf("shmctl errno %d: %s\n", errno, strerror(errno));
        return -1;
    }

    printf("shm read end\n");
    return 0;
}