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-rw-r--r--disk-utils/cramfs.h110
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diff --git a/disk-utils/cramfs.h b/disk-utils/cramfs.h
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+/*
+ * SPDX-License-Identifier: GPL-2.0-or-later
+ *
+ * cramfs_common - cramfs common code
+ *
+ * Copyright (c) 2008 Roy Peled, the.roy.peled -at- gmail
+ * 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.
+ */
+#ifndef __CRAMFS_H
+#define __CRAMFS_H
+
+#include <stdint.h>
+
+#define CRAMFS_MAGIC 0x28cd3d45 /* some random number */
+#define CRAMFS_SIGNATURE "Compressed ROMFS"
+
+/*
+ * Width of various bitfields in struct cramfs_inode.
+ * Primarily used to generate warnings in mkcramfs.
+ */
+#define CRAMFS_MODE_WIDTH 16
+#define CRAMFS_UID_WIDTH 16
+#define CRAMFS_SIZE_WIDTH 24
+#define CRAMFS_GID_WIDTH 8
+#define CRAMFS_NAMELEN_WIDTH 6
+#define CRAMFS_OFFSET_WIDTH 26
+
+#ifndef HOST_IS_BIG_ENDIAN
+#define HOST_IS_BIG_ENDIAN (__BYTE_ORDER__ == __ORDER_BIG_ENDIAN__)
+#endif
+
+/*
+ * Reasonably terse representation of the inode data.
+ */
+struct cramfs_inode {
+ uint32_t mode:16, uid:16;
+ /* SIZE for device files is i_rdev */
+ uint32_t size:24, gid:8;
+ /*
+ * NAMELEN is the length of the file name, divided by 4 and
+ * rounded up. (cramfs doesn't support hard links.)
+ *
+ * OFFSET: For symlinks and non-empty regular files, this
+ * contains the offset (divided by 4) of the file data in
+ * compressed form (starting with an array of block pointers;
+ * see README). For non-empty directories it is the offset
+ * (divided by 4) of the inode of the first file in that
+ * directory. For anything else, offset is zero.
+ */
+ uint32_t namelen:6, offset:26;
+};
+
+struct cramfs_info {
+ uint32_t crc;
+ uint32_t edition;
+ uint32_t blocks;
+ uint32_t files;
+};
+
+/*
+ * Superblock information at the beginning of the FS.
+ */
+struct cramfs_super {
+ uint32_t magic; /* 0x28cd3d45 - random number */
+ uint32_t size; /* Not used. mkcramfs currently
+ writes a constant 1<<16 here. */
+ uint32_t flags; /* 0 */
+ uint32_t future; /* 0 */
+ uint8_t signature[16]; /* "Compressed ROMFS" */
+ struct cramfs_info fsid;/* unique filesystem info */
+ uint8_t name[16]; /* user-defined name */
+ struct cramfs_inode root; /* Root inode data */
+};
+
+#define CRAMFS_FLAG_FSID_VERSION_2 0x00000001 /* fsid version #2 */
+#define CRAMFS_FLAG_SORTED_DIRS 0x00000002 /* sorted dirs */
+#define CRAMFS_FLAG_HOLES 0x00000100 /* support for holes */
+#define CRAMFS_FLAG_WRONG_SIGNATURE 0x00000200 /* reserved */
+#define CRAMFS_FLAG_SHIFTED_ROOT_OFFSET 0x00000400 /* shifted root fs */
+
+/*
+ * Valid values in super.flags. Currently we refuse to mount
+ * if (flags & ~CRAMFS_SUPPORTED_FLAGS). Maybe that should be
+ * changed to test super.future instead.
+ */
+#define CRAMFS_SUPPORTED_FLAGS (0xff)
+
+/* Uncompression interfaces to the underlying zlib */
+int cramfs_uncompress_block(void *dst, int dstlen, void *src, int srclen);
+int cramfs_uncompress_init(void);
+int cramfs_uncompress_exit(void);
+
+uint32_t u32_toggle_endianness(int big_endian, uint32_t what);
+void super_toggle_endianness(int from_big_endian, struct cramfs_super *super);
+void inode_to_host(int from_big_endian, struct cramfs_inode *inode_in,
+ struct cramfs_inode *inode_out);
+void inode_from_host(int to_big_endian, struct cramfs_inode *inode_in,
+ struct cramfs_inode *inode_out);
+
+#endif