CSK.Blog--个人原创Weblog

/******************************************************************
 *   A simple C program to retrieve the Santak(R) UPS Data
 *
 *   INTRODUCTION:
 *   ~~~~~~~~~~~~~
 *   Since the UPS monitor software WinPower provided by
 *   Santak is based on JAVA. Such implementation wastes
 *   memory and will bring troubles while running under
 *   some legacy systems.
 *
 *   So the author wrote this *light-weight * program for
 *   anyone who needs to monitor the UPS status using
 *   shell-script.
 *
 *   This program is very simple, it just requests the UPS
 *   to provide its status info via the serial port and
 *   output the response string directly to stdout.
 *
 *   The UPS will provides the following two types of status:
 *   1) standard status
 *   ----------------
 *   Request Data: "F\r"
 *   Response:     #220.0 004 12.00
 *
 *   2) current status
 *   ----------------
 *   Request Data: "Q1\r"
 *   Response:     (228.8 228.8 228.8 011 50.1 13.8 25.0 00001001
 *   
 *   You may easily decode the means of the status info
 *   with the helps of WinPower.
 *
 *   Currently, only the following model(s) has been tested:
 *   * MT-pro UPS(500/1000VA)
 *  
 *   Author Info:
 *   Shikai Chen ( csk@live.com )
 *   http://www.csksoft.net
 *
 *   Version info:
 *   Feb.07/2009
 *         ------ First version, only supports the MT-500pro model
 *
 ******************************************************************/

#include <unistd.h>
#include <stdio.h>
#include <string.h>
#include <sys/types.h>
#include <sys/stat.h>
#include <fcntl.h>
#include <termios.h>

#define UPS_COM_BRATE B2400
#define UPS_COM_DEFAULT "/dev/ttyS0"

#define WAIT_TIME 600
#define MAX_LOOP_TIME 100

//command the requires the ups to provide the standard power info
static const char * UPSCMD_STANDARD = "F\r";

//command the requires the ups to provide the current power status
static const char * UPSCMD_CURRENT  = "Q1\r";

int write_n_read
(
 int  fd,
 const  char * inbuf, unsigned int insize,
 char * outbuf, unsigned int outsize
)

{
 int nread = 0;
 int nsize = 0;
 int looptime = 0;
 write(fd,inbuf,insize);

 while((looptime++)<MAX_LOOP_TIME) {
  usleep(WAIT_TIME); //wait for response

  while((nsize=read(fd,outbuf+nread, outsize - nread))>0)
  {
   nread += nsize;

   if ( outbuf[ nread -1] == '\r' ) goto READ_FIN;
   if ( nread >= outsize) goto READ_FIN;
   
  }
 }

READ_FIN:
 return nread;
}

void set_com_prop( int fd)
{
 struct termios opt;
 
 tcgetattr(fd,&opt);

 cfsetispeed(&opt,UPS_COM_BRATE);
 cfsetospeed(&opt,UPS_COM_BRATE);

 opt.c_cflag|=(CLOCAL | CREAD);

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

 opt.c_lflag &= ~(ICANON|ECHO|ECHOE|ISIG);
 opt.c_oflag &=~OPOST;

 opt.c_cc[VTIME]=150;
 opt.c_cc[VMIN]=1;

 tcflush(fd,TCIFLUSH);

 tcsetattr(fd,TCSANOW,&opt);
}

int main( int argc, char * argv[])
{
 char recv_buff[512] = {0};
 int  fd             = 0;
 int  recv_len       = 0;
 
 char *target_port = UPS_COM_DEFAULT;
 
 //parsing argument...
 
 if ( argc > 1 ) target_port = argv[1];

 fd=open(target_port,O_RDWR|O_NOCTTY|O_NDELAY);

 
 set_com_prop(fd);
 //init connection:
 write_n_read( fd, UPSCMD_STANDARD,
        strlen( UPSCMD_STANDARD),
        recv_buff, sizeof(recv_buff));

 recv_len = write_n_read( fd,
    UPSCMD_STANDARD,
    strlen( UPSCMD_STANDARD),
    recv_buff, sizeof(recv_buff));
  
 if ( recv_len > 0 )
 {
  recv_buff[recv_len-1] = 0;
  fprintf(stdout, "%s\n", recv_buff);
 }

 while (1){

  recv_len = write_n_read( fd,
    UPSCMD_CURRENT,
    strlen( UPSCMD_CURRENT),
    recv_buff, sizeof(recv_buff));
  
  if ( recv_len > 0 )
  {
   recv_buff[recv_len - 1] = 0;

   fprintf(stdout, "%s\n", recv_buff);
  }
  sleep(1);
 }

 close(fd);
 return 0;
}