X-Git-Url: https://git.draconx.ca/gitweb/upkg.git/blobdiff_plain/83da6eb597c000ec0d28ae380adabd9c7de3f893..ebcf9b833bc750ce81951a3278065bbb86ecbdce:/test/decodeindex.c

diff --git a/test/decodeindex.c b/test/decodeindex.c
new file mode 100644
index 0000000..bbe15f4
--- /dev/null
+++ b/test/decodeindex.c
@@ -0,0 +1,165 @@
+/*
+ * Tool for decoding compact index values for testing.
+ * 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 <config.h>
+#include <stdio.h>
+#include <stdlib.h>
+#include <ctype.h>
+#include <getopt.h>
+
+#include <upkg.h>
+
+#define PROGNAME "decodeindex"
+static const char *progname = PROGNAME;
+static const unsigned char sopts[] = "VH";
+static const struct option lopts[] = {
+	{ "version", 0, NULL, 'V' },
+	{ "help",    0, NULL, 'H' },
+	{ 0 }
+};
+
+/*
+ * 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.
+ */
+static size_t 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;
+}
+
+static void print_usage(FILE *f)
+{
+	fprintf(f, "Usage: %s [options] index [index ...]\n", progname);
+}
+
+static void print_version(void)
+{
+	printf("%s (%s) %s\n", PROGNAME, PACKAGE_NAME, PACKAGE_VERSION);
+	puts("Copyright (C) 2012 Nick Bowler.");
+	puts("License GPLv3+: GNU GPL version 3 or later <http://gnu.org/licenses/gpl.html>.");
+	puts("This is free software: you are free to change and redistribute it.");
+	puts("There is NO WARRANTY, to the extent permitted by law.");
+}
+
+static void print_bytes(FILE *f, int indent, void *buf, size_t n)
+{
+	fprintf(f, "%*s", indent, "");
+	for (size_t i = 0; i < n; i++)
+		fprintf(f, "%*s%.2hhx", i != 0, "", ((unsigned char *)buf)[i]);
+	putc('\n', f);
+}
+
+static int print_index(const char *hex)
+{
+	unsigned char buf[32];
+	long index = 0;
+	size_t n, rc;
+	int ret = -1;
+
+	n = decode_hex(hex, buf, sizeof buf);
+	if (n == -1) {
+		fprintf(stderr, "%s: invalid hex sequence: %s\n",
+		                progname, hex);
+		goto out;
+	} else if (n == 0) {
+		fprintf(stderr, "%s: empty argument\n", progname);
+		goto out;
+	} else if (n > sizeof buf) {
+		fprintf(stderr, "%s: hex sequence too long: %s\n",
+		                progname, hex);
+		goto out;
+	}
+		
+	rc = upkg_decode_index(&index, buf, n);
+	if (rc == 0) {
+		fprintf(stderr, "%s: invalid index encoding:\n", progname);
+		print_bytes(stderr, 4, buf, n);
+		goto out;
+	} else if (rc < n) {
+		fprintf(stderr, "%s: trailing bytes in argument:\n", progname);
+		print_bytes(stderr, 4, buf+rc, n-rc);
+		/* Non-fatal */
+	}
+
+	ret = 0;
+out:
+	printf("%ld\n", index);
+	return ret;
+}
+
+int main(int argc, char **argv)
+{
+	int opt, ret = EXIT_SUCCESS;
+
+	if (argc > 0)
+		progname = argv[0];
+
+	while ((opt = getopt_long(argc, argv, sopts, lopts, NULL)) != -1) {
+		switch (opt) {
+		case 'V':
+			print_version();
+			return EXIT_SUCCESS;
+		case 'H':
+			print_usage(stdout);
+			return EXIT_SUCCESS;
+		default:
+			print_usage(stderr);
+			return EXIT_FAILURE;
+		}
+	}
+
+	if (!argv[optind]) {
+		print_usage(stderr);
+		return EXIT_FAILURE;
+	}
+
+	for (int i = optind; i < argc; i++) {
+		if (print_index(argv[i]) != 0) {
+			ret = EXIT_FAILURE;
+		}
+	}
+
+	return ret;
+}