mc/slang/sltoken.c

355 lines
7.0 KiB
C

/*--------------------------------*-C-*---------------------------------*
* File: sltoken.c
*
* Descript: ---
*
* Requires: ---
*
* Public: SLexpand_escaped_char ();
* SLexpand_escaped_string ();
* SLang_extract_token ();
* SLang_guess_type ();
* SLatoi ();
*
* Private: ---
*
* Notes: ---
*
* Copyright (c) 1992, 1995 John E. Davis
* All rights reserved.
*
* You may distribute under the terms of either the GNU General Public
* License or the Perl Artistic License.
\*----------------------------------------------------------------------*/
#include "config.h"
#include <stdio.h>
#ifdef HAVE_STDLIB_H
# include <stdlib.h>
#endif
#include <string.h>
#include "_slang.h"
/* There are non-zeros at positions "\t %()*,/:;[]{}" */
static unsigned char special_chars[256] =
{
/* 0 */ 0,0,0,0,0,0,0,0, 0,'\t',0,0,0,0,0,0,
/* 16 */ 0,0,0,0,0,0,0,0, 0,0,0,0,0,0,0,0,
/* 32 */ ' ',0,0,0,0,'%',0,0, '(',')','*',0,',',0,0,'/',
/* 48 */ 0,0,0,0,0,0,0,0, 0,0,':',';',0,0,0,0,
/* 64 */ 0,0,0,0,0,0,0,0, 0,0,0,0,0,0,0,0,
/* 80 */ 0,0,0,0,0,0,0,0, 0,0,0,'[',0,']',0,0,
/* 96 */ 0,0,0,0,0,0,0,0, 0,0,0,0,0,0,0,0,
/* 112 */ 0,0,0,0,0,0,0,0, 0,0,0,'{',0,'}',0,0,
/* 8-bit characters */
/* 128 */ 0,0,0,0,0,0,0,0, 0,0,0,0,0,0,0,0,
/* 144 */ 0,0,0,0,0,0,0,0, 0,0,0,0,0,0,0,0,
/* 160 */ 0,0,0,0,0,0,0,0, 0,0,0,0,0,0,0,0,
/* 176 */ 0,0,0,0,0,0,0,0, 0,0,0,0,0,0,0,0,
/* 192 */ 0,0,0,0,0,0,0,0, 0,0,0,0,0,0,0,0,
/* 208 */ 0,0,0,0,0,0,0,0, 0,0,0,0,0,0,0,0,
/* 224 */ 0,0,0,0,0,0,0,0, 0,0,0,0,0,0,0,0,
/* 240 */ 0,0,0,0,0,0,0,0, 0,0,0,0,0,0,0,0
};
char *SLexpand_escaped_char(char *p, char *ch)
{
int i = 0;
int max = 0, num, base = 0;
char ch1;
ch1 = *p++;
switch (ch1)
{
default: num = ch1; break;
case 'n': num = '\n'; break;
case 't': num = '\t'; break;
case 'v': num = '\v'; break;
case 'b': num = '\b'; break;
case 'r': num = '\r'; break;
case 'f': num = '\f'; break;
case 'E': case 'e': num = 27; break;
case 'a': num = 7;
break;
/* octal */
case '0': case '1': case '2': case '3':
case '4': case '5': case '6': case '7':
max = '7';
base = 8; i = 2; num = ch1 - '0';
break;
case 'd': /* decimal -- S-Lang extension */
base = 10;
i = 3;
max = '9';
num = 0;
break;
case 'x': /* hex */
base = 16;
max = '9';
i = 2;
num = 0;
break;
}
while (i--)
{
ch1 = *p;
if ((ch1 <= max) && (ch1 >= '0'))
{
num = base * num + (ch1 - '0');
}
else if (base == 16)
{
ch1 |= 0x20;
if ((ch1 < 'a') || ((ch1 > 'f'))) break;
num = base * num + 10 + (ch1 - 'a');
}
else break;
p++;
}
*ch = (char) num;
return p;
}
void SLexpand_escaped_string (register char *s, register char *t,
register char *tmax)
{
char ch;
while (t < tmax)
{
ch = *t++;
if (ch == '\\')
{
t = SLexpand_escaped_char (t, &ch);
}
*s++ = ch;
}
*s = 0;
}
int SLang_extract_token (char **linep, char *word_parm, int byte_comp)
{
register char ch, *line, *word = word_parm;
int string;
char ch1;
char *word_max;
word_max = word + 250;
line = *linep;
/* skip white space */
while (((ch = *line) == ' ')
|| (ch == '\t')) line++;
if ((!ch) || (ch == '\n'))
{
*linep = line;
return(0);
}
*word++ = ch;
line++;
/* Look for -something and rule out --something and -= something */
if ((ch == '-') &&
(*line != '-') && (*line != '=') && ((*line > '9') || (*line < '0')))
{
*word = 0;
*linep = line;
return 1;
}
if (ch == '"') string = 1; else string = 0;
if (ch == '\'')
{
if ((ch = *line++) != 0)
{
if (ch == '\\')
{
line = SLexpand_escaped_char(line, &ch1);
ch = ch1;
}
if (*line++ == '\'')
{
--word;
sprintf(word, "%d", (int) ((unsigned char) ch));
word += strlen (word); ch = '\'';
}
else SLang_Error = SYNTAX_ERROR;
}
else SLang_Error = SYNTAX_ERROR;
}
else if (!special_chars[(unsigned char) ch])
{
while (ch = *line++,
(ch > '"') ||
((ch != '\n') && (ch != 0) && (ch != '"')))
{
if (string)
{
if (ch == '\\')
{
ch = *line++;
if ((ch == 0) || (ch == '\n')) break;
if (byte_comp) *word++ = '\\';
else
{
line = SLexpand_escaped_char(line - 1, &ch1);
ch = ch1;
}
}
}
else if (special_chars[(unsigned char) ch])
{
line--;
break;
}
*word++ = ch;
if (word > word_max)
{
SLang_doerror ("Token to large.");
break;
}
}
}
if ((!ch) || (ch == '\n')) line--;
if ((ch == '"') && string) *word++ = '"'; else if (string) SLang_Error = SYNTAX_ERROR;
*word = 0;
*linep = line;
/* massage variable-- and ++ into --variable, etc... */
if (((int) (word - word_parm) > 2)
&& (ch = *(word - 1), (ch == '+') || (ch == '-'))
&& (ch == *(word - 2)))
{
word--;
while (word >= word_parm + 2)
{
*word = *(word - 2);
word--;
}
*word-- = ch;
*word-- = ch;
}
return(1);
}
int SLang_guess_type (char *t)
{
char *p;
register char ch;
if (*t == '-') t++;
p = t;
#ifdef FLOAT_TYPE
if (*p != '.')
{
#endif
while ((*p >= '0') && (*p <= '9')) p++;
if (t == p) return(STRING_TYPE);
if ((*p == 'x') && (p == t + 1)) /* 0x?? */
{
p++;
while (ch = *p,
((ch >= '0') && (ch <= '9'))
|| (((ch | 0x20) >= 'a') && ((ch | 0x20) <= 'f'))) p++;
}
if (*p == 0) return(INT_TYPE);
#ifndef FLOAT_TYPE
return(STRING_TYPE);
#else
}
/* now down to float case */
if (*p == '.')
{
p++;
while ((*p >= '0') && (*p <= '9')) p++;
}
if (*p == 0) return(FLOAT_TYPE);
if ((*p != 'e') && (*p != 'E')) return(STRING_TYPE);
p++;
if ((*p == '-') || (*p == '+')) p++;
while ((*p >= '0') && (*p <= '9')) p++;
if (*p != 0) return(STRING_TYPE); else return(FLOAT_TYPE);
#endif
}
int SLatoi (unsigned char *s)
{
register unsigned char ch;
register unsigned int value;
register int base;
if (*s != '0') return atoi((char *) s);
/* look for 'x' which indicates hex */
s++;
if ((*s | 0x20) == 'x')
{
base = 16;
s++;
if (*s == 0)
{
SLang_Error = SYNTAX_ERROR;
return -1;
}
}
else base = 8;
value = 0;
while ((ch = *s++) != 0)
{
char ch1 = ch | 0x20;
switch (ch1)
{
default:
SLang_Error = SYNTAX_ERROR;
break;
case '8':
case '9':
if (base != 16) SLang_Error = SYNTAX_ERROR;
/* drop */
case '0':
case '1':
case '2':
case '3':
case '4':
case '5':
case '6':
case '7':
ch1 -= '0';
break;
case 'a':
case 'b':
case 'c':
case 'd':
case 'e':
case 'f':
if (base != 16) SLang_Error = SYNTAX_ERROR;
ch1 = (ch1 - 'a') + 10;
break;
}
value = value * base + ch1;
}
return (int) value;
}