X-Git-Url: http://git.draconx.ca/gitweb/upkg.git/blobdiff_plain/94cc6656cd266c2f0d8eb5bc1201fa091744c46c..ca9488ce89bd4895db0341db393ec03696b4ebd3:/test/common.c?ds=sidebyside

diff --git a/test/common.c b/test/common.c
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+++ b/test/common.c
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+/*
+ * Helper functions for test programs.
+ * Copyright © 2012 Nick Bowler
+ *
+ * This program is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation, either version 3 of the License, or
+ * (at your option) any later version.
+ *
+ * This program 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 General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program.  If not, see <http://www.gnu.org/licenses/>.
+ */
+#include <stdlib.h>
+#include <ctype.h>
+
+#include "common.h"
+
+/*
+ * Decode a hexadecimal string into a sequence of bytes.  If there are an
+ * odd number of nibbles, treat the first character as the least significant
+ * nibble of the first byte.  The result is written to the buffer specified by
+ * buf.  At most n bytes are written to the buffer.
+ *
+ * Returns the number of bytes that would be written provided that n was large
+ * enough, or (size_t)-1 if the input is not valid.
+ */
+size_t test_decode_hex(const char *hex, unsigned char *buf, size_t n)
+{
+	size_t len, count = 0;
+	char tmp[] = "00";
+
+	for (len = 0; hex[len]; len++) {
+		if (!isxdigit(hex[len]))
+			return -1;
+	}
+
+	if (!len)
+		return 0;
+
+	switch (len % 2) {
+		while (len > 0) {
+			case 0: tmp[0] = *hex++; len--;
+			case 1: tmp[1] = *hex++; len--;
+
+			if (count < n)
+				buf[count] = strtoul(tmp, NULL, 16);
+			count++;
+		}
+	}
+
+	return count;
+}