/* File TOKEN.C BDS-C Ver 1.0 03Apr85 */
#include <bdscio.h>
#include "make.h"
 
/*
 * Get next token from the string.  Return a pointer to it, or NULL.
 * Adjust pointer to point to next part of string.
 * The string is modified.
 * A token consists of any number of non-white characters.
 */
char *token(strpp)
char **strpp;
{
	char *s, *beg;
 
	stripwh(strpp);
	if(!**strpp) return NULL;
 
	beg = s = *strpp;
	while(*s && !isspace(*s)) ++s;
	if(*s) *s++ = '\0';
	*strpp = s;
	return beg;
}
 
 
/*
 * Parse character escape-sequences in a line of text.
 *	<EscChar><EscChar> = <EscChar>
 *	<EscChar>n = newline, and so on
 *	<EscChar><char> = <char>
 * The string is truncated at the first non-escaped occurance of 'comchar'.
 */
escape(str, comchar)
char *str, comchar;
{
	char *d, c;
 
	for(d = str; *str && *str != comchar; ++str)
	    if(*str == ESCCHAR && *(str + 1)) switch((c = *++str))
		{
		   case ESCCHAR:
			*d++ = ESCCHAR;
			break;
 
		   case 'n':
			*d++ = '\n';
			break;
 
		   case 'r':
			*d++ = '\r';
			break;
 
		   case 't':
			*d++ = '\t';
			break;
 
		   case 'b':
			*d++ = '\b';
			break;
 
		   case 'f':
			*d++ = '\f';
			break;
 
		   default:
			*d++ = c;
			break;
		} else *d++ = *str;
 
	*d++ = 0;
}
 
 
stripwh(strpp)
char **strpp;
{
	char *s;
 
	s = *strpp;
	while(isspace(*s)) ++s;
	return (*strpp = s);
}