map.c

   1 /* mapping register/macro names to indices */
   2 #include <stdio.h>
   3 #include <string.h>
   4 #include "roff.h"
   5
   6 #define MAPBEG          256     /* the entries reserved for .x names */
   7
   8 /* register, macro, or environments names */
   9 static struct dict *mapdict;
  10
  11 /* map register names to [0..NREGS] */
  12 int map(char *s)
  13 {
  14         int i;
  15         if (!s[0])
  16                 return 0;
  17         if (s[0] == '.' && s[1] && !s[2])       /* ".x" is mapped to 'x' */
  18                 return (unsigned char) s[1];
  19         if (!mapdict)
  20                 mapdict = dict_make(-1, 1, 2);
  21         i = dict_idx(mapdict, s);
  22         if (i < 0) {
  23                 dict_put(mapdict, s, 0);
  24                 i = dict_idx(mapdict, s);
  25                 if (MAPBEG + i >= NREGS)
  26                         errdie("neatroff: increase NREGS\n");
  27         }
  28         return MAPBEG + i;
  29 }
  30
  31 /* return the name mapped to id; returns a static buffer */
  32 char *map_name(int id)
  33 {
  34         static char map_buf[NMLEN];
  35         if (id >= MAPBEG)
  36                 return dict_key(mapdict, id - MAPBEG);
  37         map_buf[0] = '.';
  38         map_buf[1] = id;
  39         map_buf[2] = '\0';
  40         return map_buf;
  41 }
  42
  43 void map_done(void)
  44 {
  45         if (mapdict)
  46                 dict_free(mapdict);
  47 }