cp.c

   1 #include <stdio.h>
   2 #include <stdlib.h>
   3 #include "xroff.h"
   4
   5 #define CPBUF           4
   6
   7 static int cp_nblk;             /* input block depth (text in \{ and \}) */
   8 static int cp_sblk[NIES];       /* skip \} escape at this depth, if set */
   9 static int cp_widreq = 1;       /* inline \w requests */
  10
  11 static int regid(void)
  12 {
  13         int c1;
  14         int c2 = 0;
  15         c1 = cp_next();
  16         if (c1 == '(') {
  17                 c1 = cp_next();
  18                 c2 = cp_next();
  19         }
  20         return REG(c1, c2);
  21 }
  22
  23 static void cp_num(void)
  24 {
  25         int id;
  26         int c = cp_next();
  27         if (c != '-' && c != '+')
  28                 cp_back(c);
  29         id = regid();
  30         if (c == '-' || c == '+')
  31                 num_get(id, c == '+' ? 1 : -1);
  32         if (num_str(id))
  33                 in_push(num_str(id), NULL);
  34 }
  35
  36 static void cp_str(void)
  37 {
  38         char *buf = str_get(regid());
  39         if (buf)
  40                 in_push(buf, NULL);
  41 }
  42
  43 static void cp_arg(void)
  44 {
  45         int c;
  46         char *arg = NULL;
  47         c = cp_next();
  48         if (c >= '1' && c <= '9')
  49                 arg = in_arg(c - '0');
  50         if (arg)
  51                 in_push(arg, NULL);
  52 }
  53
  54 static void cp_width(void)
  55 {
  56         char wid[16];
  57         sprintf(wid, "%d", ren_wid(cp_next, cp_back));
  58         in_push(wid, NULL);
  59 }
  60
  61 static int cp_raw(void)
  62 {
  63         int c;
  64         if (in_top() >= 0)
  65                 return in_next();
  66         c = in_next();
  67         if (c == '\\') {
  68                 c = in_next();
  69                 if (c == '\n')
  70                         return in_next();
  71                 if (c == '.')
  72                         return '.';
  73                 if (c == '{' && cp_nblk < LEN(cp_sblk))
  74                         cp_sblk[cp_nblk++] = 0;
  75                 if (c == '}' && cp_nblk > 0)
  76                         if (cp_sblk[--cp_nblk])
  77                                 return cp_raw();
  78                 cp_back(c);
  79                 return '\\';
  80         }
  81         return c;
  82 }
  83
  84 int cp_next(void)
  85 {
  86         int c;
  87         if (in_top() >= 0)
  88                 return in_next();
  89         c = cp_raw();
  90         if (c == '\\') {
  91                 c = cp_raw();
  92                 if (c == '"') {
  93                         while (c >= 0 && c != '\n')
  94                                 c = cp_raw();
  95                 } else if (c == 'w' && cp_widreq) {
  96                         cp_width();
  97                         c = cp_next();
  98                 } else if (c == 'n') {
  99                         cp_num();
 100                         c = cp_next();
 101                 } else if (c == '*') {
 102                         cp_str();
 103                         c = cp_next();
 104                 } else if (c == '$') {
 105                         cp_arg();
 106                         c = cp_next();
 107                 } else {
 108                         cp_back(c);
 109                         c = '\\';
 110                 }
 111         }
 112         return c;
 113 }
 114
 115 void cp_blk(int skip)
 116 {
 117         int c;
 118         int nblk = cp_nblk;
 119         do {
 120                 c = skip ? cp_raw() : cp_next();
 121         } while (c == ' ' || c == '\t');
 122         if (c == '\\' && in_top() == '{') {     /* a troff \{ \} block */
 123                 if (skip) {
 124                         while (skip && cp_nblk > nblk && c >= 0)
 125                                 c = cp_raw();
 126                 } else {
 127                         cp_sblk[nblk] = 1;
 128                         cp_raw();
 129                 }
 130         } else {
 131                 if (!skip)
 132                         cp_back(c);
 133         }
 134         while (skip && c != '\n')       /* skip until the end of the line */
 135                 c = cp_raw();
 136 }
 137
 138 void cp_wid(int enable)
 139 {
 140         cp_widreq = enable;
 141 }