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authorphk <phk@FreeBSD.org>1999-11-01 15:04:04 +0000
committerphk <phk@FreeBSD.org>1999-11-01 15:04:04 +0000
commitf60588ab28594d8355896a2bbd54b19f11794087 (patch)
tree4597c61920f986e1b730197efb73ade96b07b4d5 /sys/kern/subr_scanf.c
parentd4a4beb863fbb08e18b039a4ddc798f4029a7c38 (diff)
downloadFreeBSD-src-f60588ab28594d8355896a2bbd54b19f11794087.zip
FreeBSD-src-f60588ab28594d8355896a2bbd54b19f11794087.tar.gz
Add strtol & strtoul to kernel. Derived from libc versions.
Diffstat (limited to 'sys/kern/subr_scanf.c')
-rw-r--r--sys/kern/subr_scanf.c157
1 files changed, 157 insertions, 0 deletions
diff --git a/sys/kern/subr_scanf.c b/sys/kern/subr_scanf.c
index 275277f..cd6d5af 100644
--- a/sys/kern/subr_scanf.c
+++ b/sys/kern/subr_scanf.c
@@ -35,6 +35,8 @@
*
* $FreeBSD$
* From: Id: vfscanf.c,v 1.13 1998/09/25 12:20:27 obrien Exp
+ * From: static char sccsid[] = "@(#)strtol.c 8.1 (Berkeley) 6/4/93";
+ * From: static char sccsid[] = "@(#)strtoul.c 8.1 (Berkeley) 6/4/93";
*/
#include <sys/param.h>
@@ -790,3 +792,158 @@ strtoq(const char *nptr, const char **endptr, int base)
*endptr = (const char *)(any ? s - 1 : nptr);
return (acc);
}
+
+/*
+ * Convert a string to a long integer.
+ *
+ * Ignores `locale' stuff. Assumes that the upper and lower case
+ * alphabets and digits are each contiguous.
+ */
+long
+strtol(nptr, endptr, base)
+ const char *nptr;
+ const char **endptr;
+ int base;
+{
+ const char *s = nptr;
+ unsigned long acc;
+ unsigned char c;
+ unsigned long cutoff;
+ int neg = 0, any, cutlim;
+
+ /*
+ * Skip white space and pick up leading +/- sign if any.
+ * If base is 0, allow 0x for hex and 0 for octal, else
+ * assume decimal; if base is already 16, allow 0x.
+ */
+ do {
+ c = *s++;
+ } while (isspace(c));
+ if (c == '-') {
+ neg = 1;
+ c = *s++;
+ } else 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;
+
+ /*
+ * Compute the cutoff value between legal numbers and illegal
+ * numbers. That is the largest legal value, divided by the
+ * base. An input number that is greater than this value, if
+ * followed by a legal input character, is too big. One that
+ * is equal to this value may be valid or not; the limit
+ * between valid and invalid numbers is then based on the last
+ * digit. For instance, if the range for longs is
+ * [-2147483648..2147483647] and the input base is 10,
+ * cutoff will be set to 214748364 and cutlim to either
+ * 7 (neg==0) or 8 (neg==1), meaning that if we have accumulated
+ * a value > 214748364, or equal but the next digit is > 7 (or 8),
+ * the number is too big, and we will return a range error.
+ *
+ * Set any if any `digits' consumed; make it negative to indicate
+ * overflow.
+ */
+ cutoff = neg ? -(unsigned long)LONG_MIN : LONG_MAX;
+ cutlim = cutoff % (unsigned long)base;
+ cutoff /= (unsigned long)base;
+ for (acc = 0, any = 0;; c = *s++) {
+ if (!isascii(c))
+ break;
+ if (isdigit(c))
+ c -= '0';
+ else if (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 = neg ? LONG_MIN : LONG_MAX;
+ } else if (neg)
+ acc = -acc;
+ if (endptr != 0)
+ *endptr = (const char *)(any ? s - 1 : nptr);
+ return (acc);
+}
+
+/*
+ * Convert a string to an unsigned long integer.
+ *
+ * Ignores `locale' stuff. Assumes that the upper and lower case
+ * alphabets and digits are each contiguous.
+ */
+unsigned long
+strtoul(nptr, endptr, base)
+ const char *nptr;
+ const char **endptr;
+ int base;
+{
+ const char *s = nptr;
+ unsigned long acc;
+ unsigned char c;
+ unsigned long cutoff;
+ int neg = 0, any, cutlim;
+
+ /*
+ * See strtol for comments as to the logic used.
+ */
+ do {
+ c = *s++;
+ } while (isspace(c));
+ if (c == '-') {
+ neg = 1;
+ c = *s++;
+ } else 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;
+ cutoff = (unsigned long)ULONG_MAX / (unsigned long)base;
+ cutlim = (unsigned long)ULONG_MAX % (unsigned long)base;
+ for (acc = 0, any = 0;; c = *s++) {
+ if (!isascii(c))
+ break;
+ if (isdigit(c))
+ c -= '0';
+ else if (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 = ULONG_MAX;
+ } else if (neg)
+ acc = -acc;
+ if (endptr != 0)
+ *endptr = (const char *)(any ? s - 1 : nptr);
+ return (acc);
+}
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