Implement strtoimax() and strtoumax()

1 files changed, 120 insertions, 0 deletions

diff --git a/lib/libc/stdlib/strtoumax.c b/lib/libc/stdlib/strtoumax.c
new file mode 100644
index 0000000..ea59245
--- /dev/null
+++ b/lib/libc/stdlib/strtoumax.c
@@ -0,0 +1,120 @@
+/*-
+ * Copyright (c) 1992, 1993
+ *	The Regents of the University of California.  All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ * 1. Redistributions of source code must retain the above copyright
+ *    notice, this list of conditions and the following disclaimer.
+ * 2. Redistributions in binary form must reproduce the above copyright
+ *    notice, this list of conditions and the following disclaimer in the
+ *    documentation and/or other materials provided with the distribution.
+ * 3. All advertising materials mentioning features or use of this software
+ *    must display the following acknowledgement:
+ *	This product includes software developed by the University of
+ *	California, Berkeley and its contributors.
+ * 4. Neither the name of the University nor the names of its contributors
+ *    may be used to endorse or promote products derived from this software
+ *    without specific prior written permission.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
+ * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
+ * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
+ * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
+ * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
+ * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
+ * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
+ * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
+ * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
+ * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
+ * SUCH DAMAGE.
+ *
+ * $FreeBSD$
+ */
+
+#if defined(LIBC_SCCS) && !defined(lint)
+static char sccsid[] = "from @(#)strtoul.c	8.1 (Berkeley) 6/4/93";
+#endif /* LIBC_SCCS and not lint */
+
+#include <ctype.h>
+#include <errno.h>
+#include <stdlib.h>
+#include <inttypes.h>
+
+/*
+ * Convert a string to a uintmax_t integer.
+ *
+ * Assumes that the upper and lower case
+ * alphabets and digits are each contiguous.
+ */
+uintmax_t
+strtoumax(nptr, endptr, base)
+	const char *nptr;
+	char **endptr;
+	int base;
+{
+	const char *s;
+	uintmax_t acc;
+	unsigned char c;
+	uintmax_t cutoff;
+	int neg, any, cutlim;
+
+	/*
+	 * See strtoimax for comments as to the logic used.
+	 */
+	s = nptr;
+	do {
+		c = *s++;
+	} while (isspace(c));
+	if (c == '-') {
+		neg = 1;
+		c = *s++;
+	} else {
+		neg = 0;
+		if (c == '+')
+			c = *s++;
+	}
+	if ((base == 0 || base == 16) &&
+	    c == '0' && (*s == 'x' || *s == 'X')) {
+		c = s[1];
+		s += 2;
+		base = 16;
+	}
+	if (base == 0)
+		base = c == '0' ? 8 : 10;
+	acc = any = 0;
+	if (base < 2 || base > 36)
+		goto noconv;
+
+	cutoff = UINTMAX_MAX / base;
+	cutlim = UINTMAX_MAX % base;
+	for ( ; ; c = *s++) {
+		if (isxdigit(c))
+			c = digittoint(c);
+		else if (isascii(c) && isalpha(c))
+			c -= isupper(c) ? 'A' - 10 : 'a' - 10;
+		else
+			break;
+		if (c >= base)
+			break;
+		if (any < 0 || acc > cutoff || (acc == cutoff && c > cutlim))
+			any = -1;
+		else {
+			any = 1;
+			acc *= base;
+			acc += c;
+		}
+	}
+	if (any < 0) {
+		acc = UINTMAX_MAX;
+		errno = ERANGE;
+	} else if (!any) {
+noconv:
+		errno = EINVAL;
+	} else if (neg)
+		acc = -acc;
+	if (endptr != NULL)
+		*endptr = (char *)(any ? s - 1 : nptr);
+	return (acc);
+}