ebcdic.c

   1 #include "EXTERN.h"
   2 #include "perl.h"
   3
   4 /* in ASCII order, not that it matters */
   5 static const char controllablechars[] = "?@ABCDEFGHIJKLMNOPQRSTUVWXYZ[\\]^_";
   6
   7 int
   8 ebcdic_control(int ch)
   9 {
  10         if (ch > 'a') {
  11                 char *ctlp;
  12
  13                if (islower(ch))
  14                       ch = toupper(ch);
  15
  16                if ((ctlp = strchr(controllablechars, ch)) == 0) {
  17                       die("unrecognised control character '%c'\n", ch);
  18                }
  19
  20                 if (ctlp == controllablechars)
  21                        return('\177'); /* DEL */
  22                 else
  23                        return((unsigned char)(ctlp - controllablechars - 1));
  24         } else { /* Want uncontrol */
  25                 if (ch == '\177' || ch == -1)
  26                         return('?');
  27                 else if (0 < ch && ch < (sizeof(controllablechars) - 1))
  28                         return(controllablechars[ch+1]);
  29                 else
  30                         die("invalid control request: '\\%03o'\n", ch & 0xFF);
  31         }
  32 }