clients/lcdvc/vc_link.c

   1 #include <stdio.h>
   2 #include <unistd.h>
   3 #include <string.h>
   4 #include <sys/types.h>
   5 #include <sys/stat.h>
   6 #include <fcntl.h>
   7 #include <errno.h>
   8
   9 #include "lcdvc.h"
  10 #include "vc_link.h"
  11 #include "shared/report.h"
  12 #include "shared/sockets.h"
  13
  14 int vcs0, vcsa;
  15 unsigned short vc_width = 0, vc_height = 0;
  16 unsigned short vc_cursor_x = 0, vc_cursor_y = 0;
  17 char *vc_buf = NULL;
  18
  19
  20 int open_vcs(void)
  21 {
  22         /* Open the /dev/vcsX and /dev/vcsaX devices */
  23         vcs0 = open(vcs_device, O_RDONLY);
  24         if (vcs0 < 0) {
  25                 report(RPT_ERR, "Could not open %s: %s", vcs_device, strerror(errno));
  26                 return -1;
  27         }
  28         vcsa = open(vcsa_device, O_RDONLY);
  29         if (vcsa < 0) {
  30                 report(RPT_ERR, "Could not open %s: %s", vcsa_device, strerror(errno));
  31                 return -1;
  32         }
  33         return 0;
  34 }
  35
  36
  37 int read_vcdata(void)
  38 {
  39         unsigned short new_vc_height;
  40         unsigned short new_vc_width;
  41
  42         int bytes_read;
  43         unsigned char buf[20];
  44
  45         /* Read size and cursor position from /dev/vcsa */
  46         lseek(vcsa, 0, SEEK_SET);
  47         bytes_read = read(vcsa, buf, 4);
  48         if (bytes_read != 4) {
  49                 report(RPT_ERR, "Could not read from %s", vcsa_device);
  50                 return -1;
  51         }
  52         new_vc_height = buf[0];
  53         new_vc_width = buf[1];
  54         vc_cursor_x = buf[2];
  55         vc_cursor_y = buf[3];
  56
  57         /* Screen resize or initial buffer allocation ? */
  58         if ((new_vc_width != vc_width) || (new_vc_height != vc_height)) {
  59                 vc_width = new_vc_width;
  60                 vc_height = new_vc_height;
  61
  62                 if (vc_width * vc_height > 0) {
  63                         vc_buf = realloc(vc_buf, vc_width * vc_height);
  64
  65                         if (vc_buf == NULL) {
  66                                 report(RPT_ERR, "malloc failure: %s", strerror(errno));
  67                                 return -1;
  68                         }
  69                         memset(vc_buf, ' ', vc_width * vc_height);
  70                 }
  71         }
  72
  73         /* Read characters from /dev/cvs0 */
  74         lseek(vcs0, 0, SEEK_SET);
  75         bytes_read = read(vcs0, vc_buf, vc_width * vc_height);
  76         if (bytes_read != vc_width * vc_height) {
  77                 report(RPT_ERR, "Could not read from %s", vcs_device);
  78                 return -1;
  79         }
  80         return 0;
  81 }
  82