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-rw-r--r--libblkid/dos.h41
1 files changed, 41 insertions, 0 deletions
diff --git a/libblkid/dos.h b/libblkid/dos.h
new file mode 100644
index 000000000..d7588a856
--- /dev/null
+++ b/libblkid/dos.h
@@ -0,0 +1,41 @@
+#ifndef BLKID_PARTITIONS_DOS_H
+#define BLKID_PARTITIONS_DOS_H
+
+struct dos_partition {
+ unsigned char boot_ind; /* 0x80 - active */
+ unsigned char bh, bs, bc; /* begin CHS */
+ unsigned char sys_type;
+ unsigned char eh, es, ec; /* end CHS */
+ unsigned char start_sect[4];
+ unsigned char nr_sects[4];
+} __attribute__((packed));
+
+#define BLKID_MSDOS_PT_OFFSET 0x1be
+
+/* assemble badly aligned little endian integer */
+static inline unsigned int assemble4le(const unsigned char *p)
+{
+ return p[0] | (p[1] << 8) | (p[2] << 16) | (p[3] << 24);
+}
+
+static inline unsigned int dos_partition_start(struct dos_partition *p)
+{
+ return assemble4le(&(p->start_sect[0]));
+}
+
+static inline unsigned int dos_partition_size(struct dos_partition *p)
+{
+ return assemble4le(&(p->nr_sects[0]));
+}
+
+static inline int is_valid_mbr_signature(const unsigned char *mbr)
+{
+ return mbr[510] == 0x55 && mbr[511] == 0xaa ? 1 : 0;
+}
+
+static inline unsigned int dos_parttable_id(const unsigned char *mbr)
+{
+ return assemble4le(&mbr[440]);
+}
+
+#endif /* BLKID_PARTITIONS_DOS_H */