串口通用操作示例

#include <stdio.h>
#include <stdlib.h>
#include <stdint.h>
#include <string.h>
#include <unistd.h>
#include <sys/types.h>
#include <sys/stat.h>
#include <fcntl.h>
#include <termios.h>
#include <errno.h>
#include <limits.h>
#include <asm/ioctls.h>
#include <time.h>
#include <pthread.h>
#include <sys/ipc.h>
#include <sys/msg.h>

#include "lib-slip.h"

#include "util-port.h"


#define MSG   printf

static int gPortFd;
static int gMsgId;
static int gNumPort;
MutilSlipAttr_t gUartSlip = {0};

UartInfoAttr_t gUartInfo[] = {
    [0] = {
        .mPath = UART1_PATH,
        .mMode = UART_115200_8N1,
    },
    [1] = {
        .mPath = UART2_PATH,
        .mMode = UART_115200_8N1,
    },
    [2] = {
        .mPath = UART3_PATH,
        .mMode = UART_115200_8N1,
    },
    [3] = {
        .mPath = UART4_PATH,
        .mMode = UART_115200_8N1,
    },
};

int open_serial(int port){
    int fd;
    struct termios opt;

    if(!gUartInfo[port].mPath){
        return -1;
    }
    fd = open(gUartInfo[port].mPath, O_RDWR | O_NOCTTY);
    if(fd < 0){
        MSG("open uart fail.\n");
        return -1;
    }

    tcgetattr(fd, &opt);

    switch(gUartInfo[port].mMode){
        case     UART_9600_8N1:{
            cfsetispeed(&opt, B9600);
             cfsetospeed(&opt, B9600);

             opt.c_cflag &= ~PARENB;
            opt.c_cflag &= ~CSTOPB;
            opt.c_cflag &= ~CSIZE;
            opt.c_cflag |= CS8;
            break;
        }
        case     UART_9600_8O1:{
            cfsetispeed(&opt, B9600);
             cfsetospeed(&opt, B9600);

             opt.c_cflag |= PARENB;
            opt.c_cflag |= ~PARODD;
            opt.c_cflag &= ~CSTOPB;
            opt.c_cflag &= ~CSIZE;
            opt.c_cflag |= CS8;
            break;
        }
        case     UART_9600_8E1:{
            cfsetispeed(&opt, B9600);
             cfsetospeed(&opt, B9600);

             opt.c_cflag |= PARENB;
            opt.c_cflag &= ~PARODD;
            opt.c_cflag &= ~CSTOPB;
            opt.c_cflag &= ~CSIZE;
            opt.c_cflag |= CS8;
            break;
        }

        case    UART_115200_8N1:{
            cfsetispeed(&opt, B115200);
             cfsetospeed(&opt, B115200);

             opt.c_cflag &= ~PARENB;
            opt.c_cflag &= ~CSTOPB;
            opt.c_cflag &= ~CSIZE;
            opt.c_cflag |= CS8;

            break;
        }
        case    UART_115200_8O1:{
            cfsetispeed(&opt, B115200);
             cfsetospeed(&opt, B115200);

             opt.c_cflag |= PARENB;
            opt.c_cflag |= ~PARODD;
            opt.c_cflag &= ~CSTOPB;
            opt.c_cflag &= ~CSIZE;
            opt.c_cflag |= CS8;
            break;
        }
        case    UART_115200_8E1:{
            cfsetispeed(&opt, B115200);
             cfsetospeed(&opt, B115200);

             opt.c_cflag |= PARENB;
            opt.c_cflag &= ~PARODD;
            opt.c_cflag &= ~CSTOPB;
            opt.c_cflag &= ~CSIZE;
            opt.c_cflag |= CS8;
            break;
        }

        default:{
            return -1;
            //break;
        }
    }

    opt.c_lflag &= ~(ECHO | ICANON | IEXTEN | ISIG);
    opt.c_iflag &= ~(BRKINT | ICRNL | INPCK | ISTRIP | IXON);
    opt.c_oflag &= ~(OPOST);

    opt.c_cc[VMIN] = 200;
    opt.c_cc[VTIME] = 1;

    if(tcsetattr(fd, TCSANOW, &opt) < 0){
        printf("set attr error.\n");
        return -1;
    }

    tcflush(fd, TCIOFLUSH);

    return fd;
}

int stream_parse( uint8_t *p, int len ){
    UartMsgInfo_t msg;
    int ret;
    while(len--){
        ret = recv_packet(&gUartSlip, *p++);
        if(ret == 1){
            if(gUartSlip.mBuffIdx){
                //q
                msg.mType = PORT_MSG_TYPE_RCV; //must not be zero
                msg.mPayLoad.mLen = gUartSlip.mBuffIdx;
                memcpy(msg.mPayLoad.mData, gUartSlip.mBuff, gUartSlip.mBuffIdx);
                if((msgsnd(gMsgId, (void *)&msg, sizeof(UartMsgPayLoad_t), IPC_NOWAIT)) < 0){
                    printf("port%d rcv msg send error.\n", gNumPort+1);
                }
                else{
                    printf("port%d post rcv msg ok.\n", gNumPort+1);
                }
            }
        }
    }
    return 0;
}

void *port_read_thread(void *arg){
    int len;
    int iRet;
    fd_set readSet;
    uint8_t rcvBuff[UART_EACH_BUFF_RCV_MAX];


    while(1){
        FD_ZERO(&readSet);
        FD_SET (gPortFd, &readSet);

        iRet = select(gPortFd + 1, &readSet, NULL, NULL, NULL);
        if(iRet == -1){
            MSG("select error.\n");
            exit(-1);
        }
        else if(iRet == 0){
            MSG("No data, exit.\n");
            break;
        }
        else{
            //
            if(FD_ISSET(gPortFd, &readSet)){
                MSG("Port %d Rcv Data.\n", gNumPort+1);
                len = read(gPortFd, rcvBuff, UART_EACH_BUFF_RCV_MAX);
                #if 0 //test
                for(j = 0; j < len; j++)
                    MSG(" %02x", rcvBuff[j]);
                MSG("\n");
                #endif
                if(len > 0){
                    stream_parse( rcvBuff, len );
                }
            }
        }
    }
    pthread_exit(NULL);
}


void *port_write_thread(void *arg){
    UartMsgInfo_t msg;
    int i;
    int ret;
    while(1){
        if((ret = msgrcv(gMsgId, (void *)&msg, sizeof(UartMsgPayLoad_t), PORT_MSG_TYPE_SND, 0)) == -1){
            printf("port%d get snd msg error.\n", gNumPort+1);
        }
        else{
            printf("sMsg: type = %d, payloadLen = %d.\n", msg.mType, msg.mPayLoad.mLen);
            printf("     data=");
            for(i = 0; i < msg.mPayLoad.mLen; i++)
                printf(" %02x", msg.mPayLoad.mData[i]);
            printf("\n");

            if((ret = write(gPortFd, msg.mPayLoad.mData, msg.mPayLoad.mLen)) < 0){
                MSG("port%d send error.\n", gNumPort+1);
            }
            else{
                MSG("port%d send ok.\n", gNumPort+1);
            }
        }
    }

}


int main(int argc, char const *argv[])
{
    /* code */
    int key;
    int ret;
    pthread_t stid,rtid;


    if(argc != 2){
        MSG("argc error.\n");
        return -1;
    }

    gNumPort = atoi(argv[1]);
    if( (gNumPort > UART_NUM_MAX) || (gNumPort == 0)){
        MSG("serial port not existed.\n");
        return -1;
    }
    gNumPort -= 1;

    if((key = ftok(gUartInfo[gNumPort].mPath, UART_MSG_KEY)) == -1){
        MSG("port%d msg key error.\n", gNumPort+1);
        return -1;
    }

    if((gMsgId = msgget(key, IPC_CREAT|0600)) == -1){
        MSG("prot%d msg error.\n", gNumPort+1);
        return -1;
    }
    printf("port%d msg ok. qid = %d\n", gNumPort+1, gMsgId);




    if((gPortFd = open_serial(gNumPort)) <= 0){
        MSG("open serial port%d error.\n", gNumPort+1);
        return -1;
    }
    MSG("open serial %d ok.[fd=%d].\n",gNumPort+1, gPortFd);

    ret = pthread_create(&rtid, NULL, port_read_thread, NULL);
    if(ret != 0){
        MSG("port%d create port_read_thread error.\n", gNumPort+1);
        return -1;
    }

    ret = pthread_create(&stid, NULL, port_write_thread, NULL);
    if(ret != 0){
        MSG("port%d create port_write_thread error.\n", gNumPort+1);
        return -1;
    }


    pthread_join(rtid, NULL);
    pthread_join(stid, NULL);

    if(msgctl(gMsgId, IPC_RMID, NULL) < 0){
        MSG("port%d msg ctl error.\n", gNumPort+1);
    }

    return 0;
}

基于多线程实现串口自由收发