aboutsummaryrefslogtreecommitdiffstats
path: root/src/libfreeswan/libfreeswan/ttoul.c
diff options
context:
space:
mode:
Diffstat (limited to 'src/libfreeswan/libfreeswan/ttoul.c')
-rw-r--r--src/libfreeswan/libfreeswan/ttoul.c91
1 files changed, 91 insertions, 0 deletions
diff --git a/src/libfreeswan/libfreeswan/ttoul.c b/src/libfreeswan/libfreeswan/ttoul.c
new file mode 100644
index 000000000..9c6193c68
--- /dev/null
+++ b/src/libfreeswan/libfreeswan/ttoul.c
@@ -0,0 +1,91 @@
+/*
+ * convert from text form of unsigned long to binary
+ * Copyright (C) 2000 Henry Spencer.
+ *
+ * This library is free software; you can redistribute it and/or modify it
+ * under the terms of the GNU Library General Public License as published by
+ * the Free Software Foundation; either version 2 of the License, or (at your
+ * option) any later version. See <http://www.fsf.org/copyleft/lgpl.txt>.
+ *
+ * This library is distributed in the hope that it will be useful, but
+ * WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY
+ * or FITNESS FOR A PARTICULAR PURPOSE. See the GNU Library General Public
+ * License for more details.
+ *
+ * RCSID $Id: ttoul.c,v 1.1 2004/03/15 20:35:26 as Exp $
+ */
+#include "internal.h"
+#include "freeswan.h"
+
+/*
+ - ttoul - convert text substring to unsigned long number
+ */
+const char * /* NULL for success, else string literal */
+ttoul(src, srclen, base, resultp)
+const char *src;
+size_t srclen; /* 0 means strlen(src) */
+int base; /* 0 means figure it out */
+unsigned long *resultp;
+{
+ const char *stop;
+ static char hex[] = "0123456789abcdef";
+ static char uchex[] = "0123456789ABCDEF";
+ int d;
+ char c;
+ char *p;
+ unsigned long r;
+ unsigned long rlimit;
+ int dlimit;
+
+ if (srclen == 0)
+ srclen = strlen(src);
+ if (srclen == 0)
+ return "empty string";
+
+ if (base == 0) {
+ if (srclen > 2 && *src == '0' &&
+ (*(src+1) == 'x' || *(src+1) == 'X'))
+ return ttoul(src+2, srclen-2, 16, resultp);
+ if (srclen > 1 && *src == '0')
+ return ttoul(src+1, srclen-1, 8, resultp);
+ return ttoul(src, srclen, 10, resultp);
+ }
+ if (base != 8 && base != 10 && base != 16)
+ return "unsupported number base";
+
+ r = 0;
+ stop = src + srclen;
+ if (base == 16) {
+ while (src < stop) {
+ c = *src++;
+ p = strchr(hex, c);
+ if (p != NULL)
+ d = p - hex;
+ else {
+ p = strchr(uchex, c);
+ if (p == NULL)
+ return "non-hex digit in hex number";
+ d = p - uchex;
+ }
+ r = (r << 4) | d;
+ }
+ /* defer length check to catch invalid digits first */
+ if (srclen > sizeof(unsigned long) * 2)
+ return "hex number too long";
+ } else {
+ rlimit = ULONG_MAX / base;
+ dlimit = (int)(ULONG_MAX - rlimit*base);
+ while (src < stop) {
+ c = *src++;
+ d = c - '0';
+ if (d < 0 || d >= base)
+ return "non-digit in number";
+ if (r > rlimit || (r == rlimit && d > dlimit))
+ return "unsigned-long overflow";
+ r = r*base + d;
+ }
+ }
+
+ *resultp = r;
+ return NULL;
+}