Add a single, central hex blob decoder

Since we need it twice (once for tar, once for the filemap xattr
parser), add a single, central implementation to libutil, add a
unit test for that implementation and then use it in both libtar
and gensquashfs.

Signed-off-by: David Oberhollenzer <david.oberhollenzer@sigma-star.at>

2 files changed, 4 insertions, 13 deletions

diff --git a/lib/tar/internal.h b/lib/tar/internal.h
index cfbb938..c5483fe 100644
--- a/lib/tar/internal.h
+++ b/lib/tar/internal.h
@@ -11,6 +11,7 @@
 
 #include "tar/tar.h"
 #include "tar/format.h"
+#include "util/util.h"
 
 enum {
 	PAX_SIZE = 0x001,
diff --git a/lib/tar/pax_header.c b/lib/tar/pax_header.c
index 8a1b077..cc2f2b0 100644
--- a/lib/tar/pax_header.c
+++ b/lib/tar/pax_header.c
@@ -26,15 +26,6 @@ static sqfs_u8 base64_convert(char in)
 	return 0;
 }
 
-static int xdigit(int x)
-{
-	if (isupper(x))
-		return x - 'A' + 0x0A;
-	if (islower(x))
-		return x - 'a' + 0x0A;
-	return x - '0';
-}
-
 static size_t base64_decode(sqfs_u8 *out, const char *in, size_t len)
 {
 	sqfs_u8 *start = out;
@@ -91,14 +82,13 @@ static void urldecode(char *str)
 {
 	unsigned char *out = (unsigned char *)str;
 	char *in = str;
-	int x;
 
 	while (*in != '\0') {
-		x = *(in++);
+		sqfs_u8 x = *(in++);
 
 		if (x == '%' && isxdigit(in[0]) && isxdigit(in[1])) {
-			x = xdigit(*(in++)) << 4;
-			x |= xdigit(*(in++));
+			hex_decode(in, 2, &x, 1);
+			in += 2;
 		}
 
 		*(out++) = x;