git.defcon.no Git - test-repo/blob - main.c

   1 #include <termios.h>
   2 #include <errno.h>   /* Error number definitions */
   3 #include <string.h>  /* String function definitions */
   4 #include <stdio.h>
   5 #include <unistd.h>
   6 #include <fcntl.h>
   7 #include <sys/types.h>
   8
   9 #define DEVICE "/dev/ttyUSB0"
  10 #define BAUDRATE B9600
  11
  12 int open_port ( char* device )
  13 {
  14         int f;
  15         struct termios tio;
  16
  17         f = open ( DEVICE, O_RDWR | O_NOCTTY ); // Not using O_NDELAY, that caused ERR11: temp unavail.
  18         if ( f < 0 )
  19         {
  20                 perror(DEVICE);
  21                 return(-1);
  22         }
  23
  24         // Fixed settings: 9600bps, 8 bits,
  25         // no parity, no flow-control,
  26         // local mode, read enabled
  27         tio.c_cflag = BAUDRATE | CS8 | CLOCAL | CREAD;
  28         tio.c_cflag &= ~CRTSCTS;
  29         tio.c_iflag = IGNPAR;
  30         tio.c_oflag = 0;
  31         tio.c_lflag = 0; // Non-canonical read, no other options.
  32         tio.c_cc[VMIN] = 3; // Expect 3 characters, always.
  33         tio.c_cc[VTIME] = 60; // Wait for a max of 6 seconds
  34
  35         tcsetattr(f,TCSANOW,&tio); // Apply this now.
  36
  37         return f;
  38 }
  39
  40 int send_cmd ( int fd, char cmd )
  41 {
  42         int res;
  43         char buf[7];
  44         char status;
  45
  46         tcflush(fd, TCIFLUSH); // Flush the serial input buffer.
  47
  48         res = write( fd, &cmd , 1 );    // Send the command to the device
  49         if ( res < 0 ) return -1;       // and return on failure.
  50
  51         res = read( fd, buf, 5 );
  52         if ( res < 0 )
  53         {
  54                 printf("SERIAL read error %d: %s\n", errno, strerror(errno));
  55                 return -1;
  56         }
  57         if ( res == 0 )
  58         {
  59                 printf ("Null read\n");
  60                 return -1;
  61         }
  62
  63         buf[res] = 0x00;
  64
  65         // A response is supposed to be precisely three characters.
  66         if ( res != 3 ) {
  67                 return -1;
  68         }
  69
  70         // And the first is supposed to be an echo of the given command.
  71         if ( buf[0] != cmd )
  72         {
  73                 printf("Error: echoed command not correct\n");
  74                 return -1;
  75         }
  76
  77         // The second is (a ':' is ignored, and the third is checked.
  78         // The only valid responses are Locked, Open and Moving.
  79         status = buf[2];
  80
  81         if ( (status == 'O') || (status == 'L') || (status == 'M') )
  82                 return status;
  83         else return -1;
  84 }
  85
  86 int get_state ( int fd )
  87 {
  88         return send_cmd( fd, 's'); // Yashure. KISS
  89 }
  90
  91 int set_state ( int fd, int state )
  92 {
  93         int res;
  94         switch ( state )
  95         {
  96                 case 0:
  97                         res = send_cmd ( fd, 'o');
  98                         break;
  99                 case 1:
 100                         res = send_cmd ( fd, 'l');
 101                         break;
 102         }
 103         if ( (res != 'L') && ( res != 'O' ) ) return -1; // FAIL
 104         // And, yes, I will call a status "Moving" a failed state-change attempt
 105         return 0;
 106 }
 107
 108
 109 int main ( int argc, char** argv )
 110 {
 111         int fd;
 112         int res;
 113         int c;
 114         char buf[255];
 115
 116         fd = open_port( DEVICE );
 117         if ( fd < 0 )
 118         {
 119                 perror(DEVICE);
 120                 return(-1);
 121         }
 122
 123         printf("Enter command character, followed by enter/return\n");
 124         printf("Valid commands are:\n l - Lock\n o - Open \n s - Status\n i - Invalid simulation\n");
 125         printf("ESC Enter exits");
 126         printf("rdy>");
 127         for(;;)
 128         {
 129                 res = getchar();
 130                 if ( res == 10 ) continue;
 131
 132                 if ( res == 27 ) return 1;
 133                 switch( res )
 134                 {
 135                         case 'l':
 136                                 printf("Locking...\n");
 137                                 if ( set_state( fd, 1 ) ) printf ( "set_state() failed\n");
 138                                 break;
 139                         case 'o':
 140                                 printf("Opening...\n");
 141                                 if ( set_state( fd, 0 ) ) printf ( "set_state() failed\n");
 142                                 break;
 143                         case 's':
 144                                 printf("Requesting status...\n");
 145                                 res = get_state( fd );
 146                                 switch ( res )
 147                                 {
 148                                         case 'O':
 149                                                 printf("Open\n");
 150                                                 break;
 151                                         case 'L':
 152                                                 printf("Locked\n");
 153                                                 break;
 154                                         case 'M':
 155                                                 printf("Moving\n");
 156                                                 break;
 157                                         default:
 158                                                 printf("Unknown status %d\n", res);
 159                                 }
 160                                 break;
 161                         case 'i':
 162                                 printf("Sending invalid command...\n");
 163                                 res = send_cmd( fd, (char)res );
 164                                 printf("Back from attempt. Got %d back\n", res);
 165                         default:
 166                                 break;
 167                 }
 168                 printf("rdy>");
 169         }
 170 }
 171
 172