1 files changed, 71 insertions, 0 deletions
diff --git a/wsutil/bitswap.c b/wsutil/bitswap.c
new file mode 100644
index 00000000..33f78485
--- /dev/null
+++ b/wsutil/bitswap.c
@@ -0,0 +1,71 @@
+/* bitswap.c
+ * Table of bit-swapped values of bytes
+ *
+ * Wireshark - Network traffic analyzer
+ * By Gerald Combs <gerald@wireshark.org>
+ * Copyright 1998 Gerald Combs
+ *
+ *
+ * SPDX-License-Identifier: GPL-2.0-or-later
+ */
+
+#include "config.h"
+#include "bitswap.h"
+
+/* "swaptab[i]" is the value of "i" with the bits reversed. */
+static const uint8_t swaptab[256] =
+{
+  0x00, 0x80, 0x40, 0xc0, 0x20, 0xa0, 0x60, 0xe0,
+  0x10, 0x90, 0x50, 0xd0, 0x30, 0xb0, 0x70, 0xf0,
+  0x08, 0x88, 0x48, 0xc8, 0x28, 0xa8, 0x68, 0xe8,
+  0x18, 0x98, 0x58, 0xd8, 0x38, 0xb8, 0x78, 0xf8,
+  0x04, 0x84, 0x44, 0xc4, 0x24, 0xa4, 0x64, 0xe4,
+  0x14, 0x94, 0x54, 0xd4, 0x34, 0xb4, 0x74, 0xf4,
+  0x0c, 0x8c, 0x4c, 0xcc, 0x2c, 0xac, 0x6c, 0xec,
+  0x1c, 0x9c, 0x5c, 0xdc, 0x3c, 0xbc, 0x7c, 0xfc,
+  0x02, 0x82, 0x42, 0xc2, 0x22, 0xa2, 0x62, 0xe2,
+  0x12, 0x92, 0x52, 0xd2, 0x32, 0xb2, 0x72, 0xf2,
+  0x0a, 0x8a, 0x4a, 0xca, 0x2a, 0xaa, 0x6a, 0xea,
+  0x1a, 0x9a, 0x5a, 0xda, 0x3a, 0xba, 0x7a, 0xfa,
+  0x06, 0x86, 0x46, 0xc6, 0x26, 0xa6, 0x66, 0xe6,
+  0x16, 0x96, 0x56, 0xd6, 0x36, 0xb6, 0x76, 0xf6,
+  0x0e, 0x8e, 0x4e, 0xce, 0x2e, 0xae, 0x6e, 0xee,
+  0x1e, 0x9e, 0x5e, 0xde, 0x3e, 0xbe, 0x7e, 0xfe,
+  0x01, 0x81, 0x41, 0xc1, 0x21, 0xa1, 0x61, 0xe1,
+  0x11, 0x91, 0x51, 0xd1, 0x31, 0xb1, 0x71, 0xf1,
+  0x09, 0x89, 0x49, 0xc9, 0x29, 0xa9, 0x69, 0xe9,
+  0x19, 0x99, 0x59, 0xd9, 0x39, 0xb9, 0x79, 0xf9,
+  0x05, 0x85, 0x45, 0xc5, 0x25, 0xa5, 0x65, 0xe5,
+  0x15, 0x95, 0x55, 0xd5, 0x35, 0xb5, 0x75, 0xf5,
+  0x0d, 0x8d, 0x4d, 0xcd, 0x2d, 0xad, 0x6d, 0xed,
+  0x1d, 0x9d, 0x5d, 0xdd, 0x3d, 0xbd, 0x7d, 0xfd,
+  0x03, 0x83, 0x43, 0xc3, 0x23, 0xa3, 0x63, 0xe3,
+  0x13, 0x93, 0x53, 0xd3, 0x33, 0xb3, 0x73, 0xf3,
+  0x0b, 0x8b, 0x4b, 0xcb, 0x2b, 0xab, 0x6b, 0xeb,
+  0x1b, 0x9b, 0x5b, 0xdb, 0x3b, 0xbb, 0x7b, 0xfb,
+  0x07, 0x87, 0x47, 0xc7, 0x27, 0xa7, 0x67, 0xe7,
+  0x17, 0x97, 0x57, 0xd7, 0x37, 0xb7, 0x77, 0xf7,
+  0x0f, 0x8f, 0x4f, 0xcf, 0x2f, 0xaf, 0x6f, 0xef,
+  0x1f, 0x9f, 0x5f, 0xdf, 0x3f, 0xbf, 0x7f, 0xff,
+};
+
+void bitswap_buf_inplace(uint8_t *buf, size_t len)
+{
+  size_t i;
+
+  for (i = 0; i < len; i++)
+    buf[i] = swaptab[buf[i]];
+}
+
+/*
+ * Editor modelines  -  https://www.wireshark.org/tools/modelines.html
+ *
+ * Local Variables:
+ * c-basic-offset: 2
+ * tab-width: 8
+ * indent-tabs-mode: nil
+ * End:
+ *
+ * ex: set shiftwidth=2 tabstop=8 expandtab:
+ * :indentSize=2:tabSize=8:noTabs=true:
+ */