eqn/lex.c

   1 #include "e.h"
   2 #include "y.tab.h"
   3 #include <ctype.h>
   4 #include <errno.h>
   5
   6 #define SSIZE   1000
   7 char    token[SSIZE];
   8 int     sp;
   9
  10 void    space(void);
  11 void    dodef(tbl *);
  12 void    define(int);
  13 void    ifdef(void);
  14 void    include(void);
  15 void    delim(void);
  16
  17 yylex(void)
  18 {
  19         register int c;
  20         tbl *tp;
  21
  22   begin:
  23         while ((c = input()) == ' ' || c == '\n' || c == '\t')
  24                 ;
  25         yylval = c;
  26         switch (c) {
  27         case EOF:
  28                 ERROR "unexpected end of input inside equation" WARNING;
  29                 return(EOF);
  30         case '~':
  31                 return(SPACE);
  32         case '^':
  33                 return(THIN);
  34         /* case '\t':
  35                 return(TAB);
  36         */
  37         case '{':
  38                 return('{');
  39         case '}':
  40                 return('}');
  41         case '"':
  42                 for (sp = 0; (c=input())!='"' && c != '\n'; ) {
  43                         if (c == '\\')
  44                                 if ((c = input()) != '"')
  45                                         token[sp++] = '\\';
  46                         token[sp++] = c;
  47                         if (sp >= SSIZE)
  48                                 ERROR "quoted string %.20s... too long", token FATAL;
  49                 }
  50                 token[sp] = '\0';
  51                 yylval = (int) &token[0];
  52                 if (c == '\n')
  53                         ERROR "missing \" in %.20s", token WARNING;
  54                 return(QTEXT);
  55         }
  56         if (!display && c == righteq)
  57                 return(EOF);
  58
  59         unput(c);
  60         getstr(token, SSIZE);
  61         dprintf(".\tlex token = |%s|\n", token);
  62         if ((tp = lookup(deftbl, token)) != NULL) {     /* defined term */
  63                 c = input();
  64                 unput(c);
  65                 if (c == '(')   /* macro with args */
  66                         dodef(tp);
  67                 else {          /* no args */
  68                         unput(' ');
  69                         pbstr(tp->cval);
  70                         dprintf(".\tfound %s|=%s|\n", token, tp->cval);
  71                 }
  72                 goto begin;
  73         }
  74
  75         if ((tp = lookup(keytbl, token)) == NULL)       /* not a keyword */
  76                 return CONTIG;
  77
  78         switch (tp->ival) {             /* some kind of keyword */
  79         case DEFINE: case TDEFINE: case NDEFINE:
  80                 define(tp->ival);
  81                 break;
  82         case IFDEF:
  83                 ifdef();
  84                 break;
  85         case DELIM:
  86                 delim();
  87                 break;
  88         case GSIZE:
  89                 globsize();
  90                 break;
  91         case GFONT:
  92                 globfont();
  93                 break;
  94         case INCLUDE:
  95                 include();
  96                 break;
  97         case SPACE:
  98                 space();
  99                 break;
 100         case DOTEQ:
 101                         /* .EQ inside equation -- should warn if at bottom level */
 102                 break;
 103         case DOTEN:
 104                 if (curfile == infile)
 105                         return EOF;
 106                 /* else ignore nested .EN */
 107                 break;
 108         default:
 109                 return tp->ival;
 110         }
 111         goto begin;
 112 }
 113
 114 void getstr(char *s, int n)
 115 {
 116         register int c;
 117         register char *p;
 118
 119         p = s;
 120         while ((c = input()) == ' ' || c == '\n')
 121                 ;
 122         if (c == EOF) {
 123                 *s = 0;
 124                 return;
 125         }
 126         while (c != ' ' && c != '\t' && c != '\n' && c != '{' && c != '}'
 127             && c != '"' && c != '~' && c != '^') {
 128                 if (!display && c == righteq)
 129                         break;
 130                 if (c == '(' && p > s) {        /* might be defined(...) */
 131                         *p = '\0';
 132                         if (lookup(deftbl, s) != NULL)
 133                                 break;
 134                 }
 135                 if (c == '\\')
 136                         if ((c = input()) != '"')
 137                                 *p++ = '\\';
 138                 *p++ = c;
 139                 if (--n <= 0)
 140                         ERROR "token %.20s... too long", s FATAL;
 141                 c = input();
 142         }
 143         unput(c);
 144         *p = '\0';
 145         yylval = (int) s;
 146 }
 147
 148 cstr(char *s, int quote, int maxs)
 149 {
 150         int del, c, i;
 151
 152         s[0] = 0;
 153         while ((del=input()) == ' ' || del == '\t')
 154                 ;
 155         if (quote)
 156                 for (i=0; (c=input()) != del && c != EOF;) {
 157                         s[i++] = c;
 158                         if (i >= maxs)
 159                                 return(1);      /* disaster */
 160                 }
 161         else {
 162                 if (del == '\n')
 163                         return(1);
 164                 s[0] = del;
 165                 for (i=1; (c=input())!=' ' && c!= '\t' && c!='\n' && c!=EOF;) {
 166                         s[i++] = c;
 167                         if (i >= maxs)
 168                                 return(1);      /* disaster */
 169                 }
 170         }
 171         s[i] = '\0';
 172         if (c == EOF)
 173                 ERROR "Unexpected end of input at %.20s", s FATAL;
 174         return(0);
 175 }
 176
 177 void define(int type)
 178 {
 179         char *p1, *p2;
 180         extern int ftune(char *, char *);
 181
 182         getstr(token, SSIZE);   /* get name */
 183         if (type != DEFINE) {
 184                 cstr(token, 1, SSIZE);  /* skip the definition too */
 185                 return;
 186         }
 187         p1 = strsave(token);
 188         if (cstr(token, 1, SSIZE))
 189                 ERROR "Unterminated definition at %.20s", token FATAL;
 190         if (lookup(ftunetbl, p1) != NULL) {     /* double tuning param */
 191                 dprintf(".\ttune %s %s\n", p1, token);
 192                 ftune(p1, token);
 193         } else {
 194                 p2 = strsave(token);
 195                 install(deftbl, p1, p2, 0);
 196                 dprintf(".\tname %s defined as %s\n", p1, p2);
 197         }
 198 }
 199
 200 void ifdef(void)                /* do body if name is defined */
 201 {
 202         char name[100], *p;
 203
 204         getstr(name, sizeof(name));     /* get name */
 205         cstr(token, 1, SSIZE);          /* and body */
 206         if (lookup(deftbl, name) != NULL) {     /* found it */
 207                 p = strsave(token);
 208                 pushsrc(Free, p);
 209                 pushsrc(String, p);
 210         }
 211 }
 212
 213 char    *spaceval       = NULL;
 214
 215 void space(void)        /* collect line of form "space amt" to replace \x in output */
 216 {
 217         getstr(token, SSIZE);
 218         spaceval = strsave(token);
 219         dprintf(".\tsetting spaceval to %s\n", token);
 220 }
 221
 222 char *strsave(char *s)
 223 {
 224         register char *q;
 225
 226         q = malloc(strlen(s)+1);
 227         if (q == NULL)
 228                 ERROR "out of space in strsave on %s", s FATAL;
 229         strcpy(q, s);
 230         return(q);
 231 }
 232
 233 void include(void)
 234 {
 235         char name[100];
 236         FILE *fin;
 237         int c;
 238
 239         while ((c = input()) == ' ')
 240                 ;
 241         unput(c);
 242         cstr(name, c == '"', sizeof(name));     /* gets it quoted or not */
 243         if ((fin = fopen(name, "r")) == NULL)
 244                 ERROR "can't open file %s", name FATAL;
 245         errno = 0;
 246         curfile++;
 247         curfile->fin = fin;
 248         curfile->fname = strsave(name);
 249         curfile->lineno = 0;
 250         printf(".lf 1 %s\n", curfile->fname);
 251         pushsrc(File, curfile->fname);
 252 }
 253
 254 void delim(void)
 255 {
 256         yyval = eqnreg = 0;
 257         if (cstr(token, 0, SSIZE))
 258                 ERROR "Bizarre delimiters" FATAL;
 259         lefteq = token[0];
 260         righteq = token[1];
 261         if (!isprint(lefteq) || !isprint(righteq))
 262                 ERROR "Bizarre delimiters" FATAL;
 263         if (lefteq == 'o' && righteq == 'f')
 264                 lefteq = righteq = '\0';
 265 }