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-rw-r--r--disk-utils/cramfs_common.c109
1 files changed, 109 insertions, 0 deletions
diff --git a/disk-utils/cramfs_common.c b/disk-utils/cramfs_common.c
new file mode 100644
index 0000000..9fe3fa1
--- /dev/null
+++ b/disk-utils/cramfs_common.c
@@ -0,0 +1,109 @@
+/*
+ * cramfs_common - cramfs common code
+ *
+ * Copyright (c) 2008 Roy Peled, the.roy.peled -at- gmail.com
+ * Copyright (c) 2004-2006 by Juliane Holzt, kju -at- fqdn.org
+ *
+ * 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 2 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.
+ *
+ */
+
+#include <string.h>
+#include "cramfs.h"
+#include "../include/bitops.h"
+
+uint32_t u32_toggle_endianness(int big_endian, uint32_t what)
+{
+ return big_endian == HOST_IS_BIG_ENDIAN ? what : swab32(what);
+}
+
+void super_toggle_endianness(int big_endian, struct cramfs_super *super)
+{
+ if (big_endian != HOST_IS_BIG_ENDIAN) {
+ super->magic = swab32(super->magic);
+ super->size = swab32(super->size);
+ super->flags = swab32(super->flags);
+ super->future = swab32(super->future);
+ super->fsid.crc = swab32(super->fsid.crc);
+ super->fsid.edition = swab32(super->fsid.edition);
+ super->fsid.blocks = swab32(super->fsid.blocks);
+ super->fsid.files = swab32(super->fsid.files);
+ }
+}
+
+static void inode_toggle_endianness(int input_big_endian, int output_big_endian,
+ struct cramfs_inode *inode_in,
+ struct cramfs_inode *inode_out)
+{
+ if (input_big_endian == output_big_endian) {
+ memmove(inode_out, inode_in, sizeof(*inode_out));
+ } else {
+ unsigned char inode_out_buf[sizeof(*inode_in)];
+ unsigned char *inode_in_buf = (unsigned char*)inode_in;
+
+ inode_out_buf[0] = inode_in_buf[1]; /* 16 bit: mode */
+ inode_out_buf[1] = inode_in_buf[0];
+
+ inode_out_buf[2] = inode_in_buf[3]; /* 16 bit: uid */
+ inode_out_buf[3] = inode_in_buf[2];
+
+ inode_out_buf[4] = inode_in_buf[6]; /* 24 bit: size */
+ inode_out_buf[5] = inode_in_buf[5];
+ inode_out_buf[6] = inode_in_buf[4];
+
+ inode_out_buf[7] = inode_in_buf[7]; /* 8 bit: gid width */
+
+ /*
+ * Stop the madness! Outlaw C bitfields! They are unportable
+ * and nasty! See for yourself what a mess this is:
+ */
+ if (output_big_endian) {
+ inode_out_buf[ 8] = ( (inode_in_buf[ 8]&0x3F) << 2 ) |
+ ( (inode_in_buf[11]&0xC0) >> 6 );
+
+ inode_out_buf[ 9] = ( (inode_in_buf[11]&0x3F) << 2 ) |
+ ( (inode_in_buf[10]&0xC0) >> 6 );
+
+ inode_out_buf[10] = ( (inode_in_buf[10]&0x3F) << 2 ) |
+ ( (inode_in_buf[ 9]&0xC0) >> 6 );
+
+ inode_out_buf[11] = ( (inode_in_buf[ 9]&0x3F) << 2 ) |
+ ( (inode_in_buf[ 8]&0xC0) >> 6 );
+ } else {
+ inode_out_buf[ 8] = ( (inode_in_buf[ 8]&0xFD) >> 2 ) |
+ ( (inode_in_buf[11]&0x03) << 6 );
+
+ inode_out_buf[ 9] = ( (inode_in_buf[11]&0xFD) >> 2 ) |
+ ( (inode_in_buf[10]&0x03) << 6 );
+
+ inode_out_buf[10] = ( (inode_in_buf[10]&0xFD) >> 2 ) |
+ ( (inode_in_buf[ 9]&0x03) << 6 );
+
+ inode_out_buf[11] = ( (inode_in_buf[ 9]&0xFD) >> 2 ) |
+ ( (inode_in_buf[ 8]&0x03) << 6 );
+ }
+ memmove(inode_out, inode_out_buf, sizeof(*inode_out));
+ }
+}
+
+void inode_to_host(int from_big_endian, struct cramfs_inode *inode_in,
+ struct cramfs_inode *inode_out)
+{
+ inode_toggle_endianness(from_big_endian, HOST_IS_BIG_ENDIAN, inode_in,
+ inode_out);
+}
+
+void inode_from_host(int to_big_endian, struct cramfs_inode *inode_in,
+ struct cramfs_inode *inode_out)
+{
+ inode_toggle_endianness(HOST_IS_BIG_ENDIAN, to_big_endian, inode_in,
+ inode_out);
+}