libpurple/protocols/zephyr/et_name.c

   1 /*
   2  * Copyright 1987 by MIT Student Information Processing Board
   3  *
   4  * For copyright info, see mit-sipb-copyright.h.
   5  */
   6
   7 #include <sysdep.h>
   8
   9
  10 #define ERRCODE_RANGE   8       /* # of bits to shift table number */
  11 #define BITS_PER_CHAR   6       /* # bits to shift per character in name */
  12
  13
  14 static const char char_set[] =
  15         "ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz0123456789_";
  16
  17 /* Prototypes for -Wmissing-prototypes */
  18 const char * error_table_name(int num);
  19 const char * error_table_name_r(int num, char *buf);
  20
  21 const char * error_table_name_r(int num, char *buf)
  22 {
  23     int ch;
  24     int i;
  25     char *p;
  26
  27     /* num = aa aaa abb bbb bcc ccc cdd ddd d?? ??? ??? */
  28     p = buf;
  29     num >>= ERRCODE_RANGE;
  30     /* num = ?? ??? ??? aaa aaa bbb bbb ccc ccc ddd ddd */
  31     num &= 077777777;
  32     /* num = 00 000 000 aaa aaa bbb bbb ccc ccc ddd ddd */
  33     for (i = 4; i >= 0; i--) {
  34         ch = (num >> BITS_PER_CHAR * i) & ((1 << BITS_PER_CHAR) - 1);
  35         if (ch != 0)
  36             *p++ = char_set[ch-1];
  37     }
  38     *p = '\0';
  39     return(buf);
  40 }
  41
  42 const char * error_table_name(int num)
  43 {
  44     static char buf[6];
  45
  46     return(error_table_name_r(num, buf));
  47 }
  48