libc: make atoi() not parse c-style octal and hex numbers

interpreting octal breaks parsing of decimal numbers with
leading zeros. the manpage listed this in the BUGS section,
so we'r going to fix it as this just causes confusion as
most callers of atoi() do not expect it.

sys/man/2/atof

@@ -135,10 +135,3 @@ Zero is returned if the beginning of the input string is not
 interpretable as a number; even in this case,
 .I rptr
 will be updated.
-.SH BUGS
-.I Atoi,
-.I atol,
-and
-.I atoll
-accept octal and hexadecimal numbers in the style of C,
-contrary to the ANSI specification.

sys/src/libc/port/atol.c

@@ -4,50 +4,11 @@
 long
 atol(char *s)
 {
-	long n;
-	int f, c;
-
-	n = 0;
-	f = 0;
-	while(*s == ' ' || *s == '\t')
-		s++;
-	if(*s == '-' || *s == '+') {
-		if(*s++ == '-')
-			f = 1;
-		while(*s == ' ' || *s == '\t')
-			s++;
-	}
-	if(s[0]=='0' && s[1]) {
-		if(s[1]=='x' || s[1]=='X'){
-			s += 2;
-			for(;;) {
-				c = *s;
-				if(c >= '0' && c <= '9')
-					n = n*16 + c - '0';
-				else
-				if(c >= 'a' && c <= 'f')
-					n = n*16 + c - 'a' + 10;
-				else
-				if(c >= 'A' && c <= 'F')
-					n = n*16 + c - 'A' + 10;
-				else
-					break;
-				s++;
-			}
-		} else
-			while(*s >= '0' && *s <= '7')
-				n = n*8 + *s++ - '0';
-	} else
-		while(*s >= '0' && *s <= '9')
-			n = n*10 + *s++ - '0';
-	if(f)
-		n = -n;
-	return n;
+	return strtol(s, nil, 10);
 }
 
 int
 atoi(char *s)
 {
-
-	return atol(s);
+	return strtol(s, nil, 10);
 }

sys/src/libc/port/atoll.c

@@ -4,5 +4,5 @@
 vlong
 atoll(char *s)
 {
-	return strtoll(s, nil, 0);
+	return strtoll(s, nil, 10);
 }