rosapps/mc/slang/sltoken.c

   1 /*--------------------------------*-C-*---------------------------------*
   2  * File:        sltoken.c
   3  *
   4  * Descript:    ---
   5  *
   6  * Requires:    ---
   7  *
   8  * Public:      SLexpand_escaped_char ();
   9  *              SLexpand_escaped_string ();
  10  *              SLang_extract_token ();
  11  *              SLang_guess_type ();
  12  *              SLatoi ();
  13  *
  14  * Private:     ---
  15  *
  16  * Notes:       ---
  17  *
  18  * Copyright (c) 1992, 1995 John E. Davis
  19  * All rights reserved.
  20  *
  21  * You may distribute under the terms of either the GNU General Public
  22  * License or the Perl Artistic License.
  23 \*----------------------------------------------------------------------*/
  24
  25 #include "config.h"
  26
  27 #include <stdio.h>
  28
  29
  30 #ifdef HAVE_STDLIB_H
  31 # include <stdlib.h>
  32 #endif
  33 #include <string.h>
  34 #include "slang.h"
  35 #include "_slang.h"
  36
  37 /* There are non-zeros at positions "\t %()*,/:;[]{}" */
  38
  39 static unsigned char special_chars[256] =
  40 {
  41    /* 0 */      0,0,0,0,0,0,0,0,        0,'\t',0,0,0,0,0,0,
  42    /* 16 */     0,0,0,0,0,0,0,0,        0,0,0,0,0,0,0,0,
  43    /* 32 */     ' ',0,0,0,0,'%',0,0,    '(',')','*',0,',',0,0,'/',
  44    /* 48 */     0,0,0,0,0,0,0,0,        0,0,':',';',0,0,0,0,
  45    /* 64 */     0,0,0,0,0,0,0,0,        0,0,0,0,0,0,0,0,
  46    /* 80 */     0,0,0,0,0,0,0,0,        0,0,0,'[',0,']',0,0,
  47    /* 96 */     0,0,0,0,0,0,0,0,        0,0,0,0,0,0,0,0,
  48    /* 112 */    0,0,0,0,0,0,0,0,        0,0,0,'{',0,'}',0,0,
  49    /* 8-bit characters */
  50    /* 128 */    0,0,0,0,0,0,0,0,        0,0,0,0,0,0,0,0,
  51    /* 144 */    0,0,0,0,0,0,0,0,        0,0,0,0,0,0,0,0,
  52    /* 160 */    0,0,0,0,0,0,0,0,        0,0,0,0,0,0,0,0,
  53    /* 176 */    0,0,0,0,0,0,0,0,        0,0,0,0,0,0,0,0,
  54    /* 192 */    0,0,0,0,0,0,0,0,        0,0,0,0,0,0,0,0,
  55    /* 208 */    0,0,0,0,0,0,0,0,        0,0,0,0,0,0,0,0,
  56    /* 224 */    0,0,0,0,0,0,0,0,        0,0,0,0,0,0,0,0,
  57    /* 240 */    0,0,0,0,0,0,0,0,        0,0,0,0,0,0,0,0
  58 };
  59
  60 char *SLexpand_escaped_char(char *p, char *ch)
  61 {
  62    int i = 0;
  63    int max = 0, num, base = 0;
  64    char ch1;
  65
  66    ch1 = *p++;
  67
  68    switch (ch1)
  69      {
  70       default: num = ch1; break;
  71       case 'n': num = '\n'; break;
  72       case 't': num = '\t'; break;
  73       case 'v': num = '\v'; break;
  74       case 'b': num = '\b'; break;
  75       case 'r': num = '\r'; break;
  76       case 'f': num = '\f'; break;
  77       case 'E': case 'e': num = 27; break;
  78       case 'a': num = 7;
  79         break;
  80
  81         /* octal */
  82       case '0': case '1': case '2': case '3':
  83       case '4': case '5': case '6': case '7':
  84         max = '7';
  85         base = 8; i = 2; num = ch1 - '0';
  86         break;
  87
  88       case 'd':                        /* decimal -- S-Lang extension */
  89         base = 10;
  90         i = 3;
  91         max = '9';
  92         num = 0;
  93         break;
  94
  95       case 'x':                        /* hex */
  96         base = 16;
  97         max = '9';
  98         i = 2;
  99         num = 0;
 100         break;
 101      }
 102
 103    while (i--)
 104      {
 105         ch1 = *p;
 106
 107         if ((ch1 <= max) && (ch1 >= '0'))
 108           {
 109              num = base * num + (ch1 - '0');
 110           }
 111         else if (base == 16)
 112           {
 113              ch1 |= 0x20;
 114              if ((ch1 < 'a') || ((ch1 > 'f'))) break;
 115              num = base * num + 10 + (ch1 - 'a');
 116           }
 117         else break;
 118         p++;
 119      }
 120
 121    *ch = (char) num;
 122    return p;
 123 }
 124
 125 void SLexpand_escaped_string (register char *s, register char *t,
 126                               register char *tmax)
 127 {
 128    char ch;
 129
 130    while (t < tmax)
 131      {
 132         ch = *t++;
 133         if (ch == '\\')
 134           {
 135              t = SLexpand_escaped_char (t, &ch);
 136           }
 137         *s++ = ch;
 138      }
 139    *s = 0;
 140 }
 141
 142
 143 int SLang_extract_token (char **linep, char *word_parm, int byte_comp)
 144 {
 145    register char ch, *line, *word = word_parm;
 146    int string;
 147    char ch1;
 148    char *word_max;
 149
 150    word_max = word + 250;
 151
 152    line = *linep;
 153
 154    /* skip white space */
 155    while (((ch = *line) == ' ')
 156           || (ch == '\t')) line++;
 157
 158    if ((!ch) || (ch == '\n'))
 159      {
 160         *linep = line;
 161         return(0);
 162      }
 163
 164    *word++ = ch;
 165    line++;
 166
 167    /* Look for -something and rule out --something and -= something */
 168    if ((ch == '-') &&
 169        (*line != '-') && (*line != '=') && ((*line > '9') || (*line < '0')))
 170      {
 171         *word = 0;
 172         *linep = line;
 173         return 1;
 174      }
 175
 176
 177    if (ch == '"') string = 1; else string = 0;
 178    if (ch == '\'')
 179      {
 180         if ((ch = *line++) != 0)
 181           {
 182              if (ch == '\\')
 183                {
 184                   line = SLexpand_escaped_char(line, &ch1);
 185                   ch = ch1;
 186                }
 187              if (*line++ == '\'')
 188                {
 189                   --word;
 190                   sprintf(word, "%d", (int) ((unsigned char) ch));
 191                   word += strlen (word);  ch = '\'';
 192                }
 193              else SLang_Error = SYNTAX_ERROR;
 194           }
 195         else SLang_Error = SYNTAX_ERROR;
 196      }
 197    else  if (!special_chars[(unsigned char) ch])
 198      {
 199         while (ch = *line++,
 200                (ch > '"') ||
 201                ((ch != '\n') && (ch != 0) && (ch != '"')))
 202           {
 203              if (string)
 204                {
 205                   if (ch == '\\')
 206                     {
 207                        ch = *line++;
 208                        if ((ch == 0) || (ch == '\n')) break;
 209                        if (byte_comp) *word++ = '\\';
 210                        else
 211                          {
 212                             line = SLexpand_escaped_char(line - 1, &ch1);
 213                             ch = ch1;
 214                          }
 215                     }
 216                }
 217              else if (special_chars[(unsigned char) ch])
 218                {
 219                   line--;
 220                   break;
 221                }
 222
 223              *word++ = ch;
 224              if (word > word_max)
 225                {
 226                   SLang_doerror ("Token to large.");
 227                   break;
 228                }
 229           }
 230      }
 231
 232    if ((!ch) || (ch == '\n')) line--;
 233    if ((ch == '"') && string) *word++ = '"'; else if (string) SLang_Error = SYNTAX_ERROR;
 234    *word = 0;
 235    *linep = line;
 236    /* massage variable-- and ++ into --variable, etc... */
 237    if (((int) (word - word_parm) > 2)
 238        && (ch = *(word - 1), (ch == '+') || (ch == '-'))
 239        && (ch == *(word - 2)))
 240      {
 241         word--;
 242         while (word >= word_parm + 2)
 243           {
 244              *word = *(word - 2);
 245              word--;
 246           }
 247         *word-- = ch;
 248         *word-- = ch;
 249      }
 250    return(1);
 251 }
 252
 253
 254 int SLang_guess_type (char *t)
 255 {
 256    char *p;
 257    register char ch;
 258
 259    if (*t == '-') t++;
 260    p = t;
 261 #ifdef FLOAT_TYPE
 262    if (*p != '.')
 263      {
 264 #endif
 265         while ((*p >= '0') && (*p <= '9')) p++;
 266         if (t == p) return(STRING_TYPE);
 267         if ((*p == 'x') && (p == t + 1))   /* 0x?? */
 268           {
 269              p++;
 270              while (ch = *p,
 271                     ((ch >= '0') && (ch <= '9'))
 272                     || (((ch | 0x20) >= 'a') && ((ch | 0x20) <= 'f'))) p++;
 273           }
 274         if (*p == 0) return(INT_TYPE);
 275 #ifndef FLOAT_TYPE
 276         return(STRING_TYPE);
 277 #else
 278      }
 279
 280    /* now down to float case */
 281    if (*p == '.')
 282      {
 283         p++;
 284         while ((*p >= '0') && (*p <= '9')) p++;
 285      }
 286    if (*p == 0) return(FLOAT_TYPE);
 287    if ((*p != 'e') && (*p != 'E')) return(STRING_TYPE);
 288    p++;
 289    if ((*p == '-') || (*p == '+')) p++;
 290    while ((*p >= '0') && (*p <= '9')) p++;
 291    if (*p != 0) return(STRING_TYPE); else return(FLOAT_TYPE);
 292 #endif
 293 }
 294
 295 int SLatoi (unsigned char *s)
 296 {
 297    register unsigned char ch;
 298    register unsigned int value;
 299    register int base;
 300
 301    if (*s != '0') return atoi((char *) s);
 302
 303    /* look for 'x' which indicates hex */
 304    s++;
 305    if ((*s | 0x20) == 'x')
 306      {
 307         base = 16;
 308         s++;
 309         if (*s == 0)
 310           {
 311              SLang_Error = SYNTAX_ERROR;
 312              return -1;
 313           }
 314      }
 315    else base = 8;
 316
 317
 318    value = 0;
 319    while ((ch = *s++) != 0)
 320      {
 321         char ch1 = ch | 0x20;
 322         switch (ch1)
 323           {
 324            default:
 325              SLang_Error = SYNTAX_ERROR;
 326              break;
 327            case '8':
 328            case '9':
 329              if (base != 16) SLang_Error = SYNTAX_ERROR;
 330              /* drop */
 331            case '0':
 332            case '1':
 333            case '2':
 334            case '3':
 335            case '4':
 336            case '5':
 337            case '6':
 338            case '7':
 339              ch1 -= '0';
 340              break;
 341
 342            case 'a':
 343            case 'b':
 344            case 'c':
 345            case 'd':
 346            case 'e':
 347            case 'f':
 348              if (base != 16) SLang_Error = SYNTAX_ERROR;
 349              ch1 = (ch1 - 'a') + 10;
 350              break;
 351           }
 352         value = value * base + ch1;
 353      }
 354    return (int) value;
 355 }