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-rw-r--r--src/include/fs/fat.h100
1 files changed, 100 insertions, 0 deletions
diff --git a/src/include/fs/fat.h b/src/include/fs/fat.h
new file mode 100644
index 0000000000..7fed6bacb3
--- /dev/null
+++ b/src/include/fs/fat.h
@@ -0,0 +1,100 @@
+/*
+ * GRUB -- GRand Unified Bootloader
+ * Copyright (C) 2001 Free Software Foundation, Inc.
+ *
+ * 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.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
+ */
+
+
+/*
+ * Defines for the FAT BIOS Parameter Block (embedded in the first block
+ * of the partition.
+ */
+
+typedef __signed__ char __s8;
+typedef unsigned char __u8;
+typedef __signed__ short __s16;
+typedef unsigned short __u16;
+typedef __signed__ int __s32;
+typedef unsigned int __u32;
+
+/* Note that some shorts are not aligned, and must therefore
+ * be declared as array of two bytes.
+ */
+struct fat_bpb {
+ __s8 ignored[3]; /* Boot strap short or near jump */
+ __s8 system_id[8]; /* Name - can be used to special case
+ partition manager volumes */
+ __u8 bytes_per_sect[2]; /* bytes per logical sector */
+ __u8 sects_per_clust;/* sectors/cluster */
+ __u8 reserved_sects[2]; /* reserved sectors */
+ __u8 num_fats; /* number of FATs */
+ __u8 dir_entries[2]; /* root directory entries */
+ __u8 short_sectors[2]; /* number of sectors */
+ __u8 media; /* media code (unused) */
+ __u16 fat_length; /* sectors/FAT */
+ __u16 secs_track; /* sectors per track */
+ __u16 heads; /* number of heads */
+ __u32 hidden; /* hidden sectors (unused) */
+ __u32 long_sectors; /* number of sectors (if short_sectors == 0) */
+
+ /* The following fields are only used by FAT32 */
+ __u32 fat32_length; /* sectors/FAT */
+ __u16 flags; /* bit 8: fat mirroring, low 4: active fat */
+ __u8 version[2]; /* major, minor filesystem version */
+ __u32 root_cluster; /* first cluster in root directory */
+ __u16 info_sector; /* filesystem info sector */
+ __u16 backup_boot; /* backup boot sector */
+ __u16 reserved2[6]; /* Unused */
+};
+
+#define FAT_CVT_U16(bytarr) (* (__u16*)(bytarr))
+
+/*
+ * Defines how to differentiate a 12-bit and 16-bit FAT.
+ */
+
+#define FAT_MAX_12BIT_CLUST 4087 /* 4085 + 2 */
+
+/*
+ * Defines for the file "attribute" byte
+ */
+
+#define FAT_ATTRIB_OK_MASK 0x37
+#define FAT_ATTRIB_NOT_OK_MASK 0xC8
+#define FAT_ATTRIB_DIR 0x10
+#define FAT_ATTRIB_LONGNAME 0x0F
+
+/*
+ * Defines for FAT directory entries
+ */
+
+#define FAT_DIRENTRY_LENGTH 32
+
+#define FAT_DIRENTRY_ATTRIB(entry) \
+ (*((unsigned char *) (entry+11)))
+#define FAT_DIRENTRY_VALID(entry) \
+ ( ((*((unsigned char *) entry)) != 0) \
+ && ((*((unsigned char *) entry)) != 0xE5) \
+ && !(FAT_DIRENTRY_ATTRIB(entry) & FAT_ATTRIB_NOT_OK_MASK) )
+#define FAT_DIRENTRY_FIRST_CLUSTER(entry) \
+ ((*((unsigned short *) (entry+26)))+(*((unsigned short *) (entry+20)) << 16))
+#define FAT_DIRENTRY_FILELENGTH(entry) \
+ (*((unsigned long *) (entry+28)))
+
+#define FAT_LONGDIR_ID(entry) \
+ (*((unsigned char *) (entry)))
+#define FAT_LONGDIR_ALIASCHECKSUM(entry) \
+ (*((unsigned char *) (entry+13)))