add LCC - a better C-Compiler for WEGA

WEGA/contrib/lcc/lib/libc/port/stdio/doscan.c

@@ -0,0 +1,232 @@
+#include <stdio.h>
+#include <ctype.h>
+#include <varargs.h>
+#include <values.h>
+
+#define NCHARS	(1 << BITSPERBYTE)
+
+extern double atof();
+extern char *memset();
+extern int ungetc();
+
+int
+_doscan(iop, fmt, va_alist)
+register FILE *iop;
+register unsigned char *fmt;
+va_list va_alist;
+{
+	extern unsigned char *setup();
+	char tab[NCHARS];
+	register int ch;
+	int nmatch = 0, len, inchar, stow, size;
+
+	/*******************************************************
+	 * Main loop: reads format to determine a pattern,
+	 *		and then goes to read input stream
+	 *		in attempt to match the pattern.
+	 *******************************************************/
+	for( ; ; ) {
+		if((ch = *fmt++) == '\0')
+			return(nmatch); /* end of format */
+		if(isspace(ch)) {
+			while(isspace(inchar = getc(iop)))
+				;
+			if(ungetc(inchar, iop) != EOF)
+				continue;
+			break;
+		}
+		if(ch != '%' || (ch = *fmt++) == '%') {
+			if((inchar = getc(iop)) == ch)
+				continue;
+			if(ungetc(inchar, iop) != EOF)
+				return(nmatch); /* failed to match input */
+			break;
+		}
+		if(ch == '*') {
+			stow = 0;
+			ch = *fmt++;
+		} else
+			stow = 1;
+
+		for(len = 0; isdigit(ch); ch = *fmt++)
+			len = len * 10 + ch - '0';
+		if(len == 0)
+			len = MAXINT;
+
+		if((size = ch) == 'l' || size == 'h')
+			ch = *fmt++;
+		if(ch == '\0' ||
+		    ch == '[' && (fmt = setup(fmt, tab)) == NULL)
+			return(EOF); /* unexpected end of format */
+		if(isupper(ch)) { /* no longer documented */
+			size = 'l';
+			ch = _tolower(ch);
+		}
+		if(ch != 'c' && ch != '[') {
+			while(isspace(inchar = getc(iop)))
+				;
+			if(ungetc(inchar, iop) == EOF)
+				break;
+		}
+		if((size = (ch == 'c' || ch == 's' || ch == '[') ?
+		    string(stow, ch, len, tab, iop, &va_alist) :
+		    number(stow, ch, len, size, iop, &va_alist)) != 0)
+			nmatch += stow;
+		if(va_alist == NULL) /* end of input */
+			break;
+		if(size == 0)
+			return(nmatch); /* failed to match input */
+	}
+	return(nmatch != 0 ? nmatch : EOF); /* end of input */
+}
+
+/***************************************************************
+ * Functions to read the input stream in an attempt to match incoming
+ * data to the current pattern from the main loop of _doscan().
+ ***************************************************************/
+static int
+number(stow, type, len, size, iop, listp)
+int stow, type, len, size;
+register FILE *iop;
+va_list *listp;
+{
+	char numbuf[64];
+	register char *np = numbuf;
+	register int c, base;
+	int digitseen = 0, dotseen = 0, expseen = 0, floater = 0, negflg = 0;
+	long lcval = 0;
+
+	switch(type) {
+	case 'e':
+	case 'f':
+	case 'g':
+		floater++;
+	case 'd':
+	case 'u':
+		base = 10;
+		break;
+	case 'o':
+		base = 8;
+		break;
+	case 'x':
+		base = 16;
+		break;
+	default:
+		return(0); /* unrecognized conversion character */
+	}
+	switch(c = getc(iop)) {
+	case '-':
+		negflg++;
+	case '+': /* fall-through */
+		len--;
+		c = getc(iop);
+	}
+	for( ; --len >= 0; *np++ = c, c = getc(iop)) {
+		if(isdigit(c) || base == 16 && isxdigit(c)) {
+			int digit = c - (isdigit(c) ? '0' :
+			    isupper(c) ? 'A' - 10 : 'a' - 10);
+			if(digit >= base)
+				break;
+			if(stow && !floater)
+				lcval = base * lcval + digit;
+			digitseen++;
+			continue;
+		}
+		if(!floater)
+			break;
+		if(c == '.' && !dotseen++)
+			continue;
+		if((c == 'e' || c == 'E') && digitseen && !expseen++) {
+			*np++ = c;
+			c = getc(iop);
+			if(isdigit(c) || c == '+' || c == '-')
+				continue;
+		}
+		break;
+	}
+	if(stow && digitseen)
+		if(floater) {
+			register double dval;
+	
+			*np = '\0';
+			dval = atof(numbuf);
+			if(negflg)
+				dval = -dval;
+			if(size == 'l')
+				*va_arg(*listp, double *) = dval;
+			else
+				*va_arg(*listp, float *) = (float)dval;
+		} else {
+			/* suppress possible overflow on 2's-comp negation */
+			if(negflg && lcval != HIBITL)
+				lcval = -lcval;
+			if(size == 'l')
+				*va_arg(*listp, long *) = lcval;
+			else if(size == 'h')
+				*va_arg(*listp, short *) = (short)lcval;
+			else
+				*va_arg(*listp, int *) = (int)lcval;
+		}
+	if(ungetc(c, iop) == EOF)
+		*listp = NULL; /* end of input */
+	return(digitseen); /* successful match if non-zero */
+}
+
+static int
+string(stow, type, len, tab, iop, listp)
+register int stow, type, len;
+register char *tab;
+register FILE *iop;
+va_list *listp;
+{
+	register int ch;
+	register char *ptr;
+	char *start;
+
+	start = ptr = stow ? va_arg(*listp, char *) : NULL;
+	if(type == 'c' && len == MAXINT)
+		len = 1;
+	while((ch = getc(iop)) != EOF &&
+	    !(type == 's' && isspace(ch) || type == '[' && tab[ch])) {
+		if(stow)
+			*ptr = ch;
+		ptr++;
+		if(--len <= 0)
+			break;
+	}
+	if(ch == EOF || len > 0 && ungetc(ch, iop) == EOF)
+		*listp = NULL; /* end of input */
+	if(ptr == start)
+		return(0); /* no match */
+	if(stow && type != 'c')
+		*ptr = '\0';
+	return(1); /* successful match */
+}
+
+static unsigned char *
+setup(fmt, tab)
+register unsigned char *fmt;
+register char *tab;
+{
+	register int b, c, d, t = 0;
+
+	if(*fmt == '^') {
+		t++;
+		fmt++;
+	}
+	(void)memset(tab, !t, NCHARS);
+	if((c = *fmt) == ']' || c == '-') { /* first char is special */
+		tab[c] = t;
+		fmt++;
+	}
+	while((c = *fmt++) != ']') {
+		if(c == '\0')
+			return(NULL); /* unexpected end of format */
+		if(c == '-' && (d = *fmt) != ']' && (b = fmt[-2]) < d) {
+			(void)memset(&tab[b], t, d - b);
+			fmt++;
+		} else
+			tab[c] = t;
+	}
+	return(fmt);
+}