ttycontrl.c

linux系统下3G模块守护进程测试源代码

/**************************************************************


Description: 3G test program. Use AT-command: "AT+CGMI"

$Log: 
**************************************************************/

//===================================================
// head files
//===================================================
#include "3GDaemon.h"

//===================================================
// Global variables 
//=================================================== 
int gComFp;              // pointer of device file
extern FILE *logfile;
//===================================================
// Functions
//===================================================
/*****************************************
Function:     OpenCom
Description:  Open a device file
Parameter: 
    deviceName[input]: Path of device file
Return:
    SUCCEED: succeed to open files
      ERROR: failed to open files
Remark:
******************************************/
int OpenCom(const char *deviceName) 
{  
    char msg[BUFFER_LEN];
    struct termios newTio; // Attributions of terminal 
    
    // Try to open a device file
    if ((gComFp = open(deviceName, O_RDWR|O_EXCL|O_NONBLOCK|O_NOCTTY)) == FAIL)
    { 
        sprintf(msg, "Can't open 3G device %s.\n", deviceName);
        log_message(logfile, msg);
        return ERROR;
    }
   
    // Get the default attributions
    tcgetattr(gComFp, &newTio);    
    bzero(&newTio, sizeof(newTio));  
    
    // Setting control mode flag  
    newTio.c_cflag |= CREAD;
    newTio.c_cflag &= ~CLOCAL;  
    newTio.c_cflag &= ~PARENB;  
    newTio.c_cflag &= ~PARODD;  
    newTio.c_cflag &= ~CSTOPB;  
    newTio.c_cflag &= ~CSIZE;    
    newTio.c_cflag |= CS8;  
    newTio.c_oflag |= OPOST;  
  
    // Setting input, output and local mode flag  
    newTio.c_iflag &= ~(IGNCR | ICRNL | IUCLC | INPCK | IXON | IXANY | IGNPAR );
    newTio.c_oflag &= ~(OPOST | OLCUC | OCRNL | ONLCR | ONLRET);
    newTio.c_lflag &= ~(ICANON | XCASE | ECHO | ECHOE | ECHONL);
    newTio.c_lflag &= ~(ECHO | ECHOE);

    // Set timeout, but it's said no use.
    newTio.c_cc[VMIN] = 1;  // Do not update the options and do it
    newTio.c_cc[VTIME] = 0; // Timeout 0 seconds
    newTio.c_cc[VEOF] = 1;

    // Set baudrate
    cfsetispeed(&newTio, BAUDRATE);  
    cfsetospeed(&newTio, BAUDRATE);
    
    // Enable the setting
    tcflush(gComFp, TCIFLUSH);

    // Set attributions    
    if (tcsetattr(gComFp, TCSANOW, &newTio) != SUCCEED)
    {
        log_message(logfile, "Setup Serial port error!\n");
        return ERROR;   
    }    
   
    return SUCCEED;  
}  

/*****************************************
Function:     ReadCom
Description:  read data from device
Parameter: 
     buffer[input]: buffer of data read from device
    readLen[input]: length of data want to read
Return:
    SUCCEED: read succeed
      ERROR: read failed
Remark:
******************************************/
int ReadCom(unsigned char *buffer, int readLen)  
{  
    fd_set readSet;
    struct timeval timeout; // strut of timeout
    int realReadLen; // length of data really read from device
    int ret; // value for return from select() 

    if (gComFp == 0)
    {
        log_message(logfile, "Read Serial error: Device not open!\n");
        return ERROR;
    }
    
    timeout.tv_sec = ZERO_LEN; // set time for timeout (s)
    timeout.tv_usec = DELAY_FOR_READ_TIME; // set time for timeout (us)
    
    // set block for reading 
    FD_ZERO(&readSet);
    FD_SET(gComFp, &readSet);

    // wait for ready state for reading
    ret=select(gComFp+1, &readSet, NULL, NULL, &timeout);

    if (ret)
    {
        // read data from device
        realReadLen = read(gComFp, buffer, readLen);
        if (realReadLen > ZERO_LEN)
        {  
            buffer[realReadLen+1] = '\0';
            return SUCCEED;
        }
        else
        {
            log_message(logfile, "Read Serial error: read nothing!\n");
            return ERROR; // Read nothing
        }
    }
    else 
    {
        log_message(logfile, "Read Serial error: device not ready!\n");
        return ERROR; // Not ready for reading after timeout
    }
}

/*****************************************
Function:     WriteCom
Description:  Write data to device
Parameter: 
    buffer[input]: buffer of data want to write
Return:
    SUCCEED: write succeed
      ERROR: write failed
Remark:
******************************************/
int WriteCom(unsigned char *buffer)  
{  
    if (strlen(buffer) <= ZERO_LEN)
    {
        log_message(logfile, "Write Serial error: String is empty!\n");        
        return ERROR;
    }
    if (gComFp == 0)
    {
        log_message(logfile, "Write Serial error: Can not write to 3G device!\n"); 
        return ERROR;
    }
    int writeLen;
    writeLen = write(gComFp, buffer, strlen(buffer));  
    if (writeLen <= ZERO_LEN)  
    {
        log_message(logfile, "Write Serial error: Not all chars were sended!\n"); 
        return ERROR;
    }
    return SUCCEED;
}

int SendAtCommand(char *comd)
{
    WriteCom(comd);
    return 0;
}

int ReceiveResponse(char *repBuffer)
{
    if (ReadCom(repBuffer, BUF_MAX_SIZE) != SUCCEED) // read from device
    {
        log_message(logfile, "Read Serial error: read failed!\n"); 
        return ERROR;
    }
    return SUCCEED;
}