patch-1.3.94 linux/fs/affs/amigaffs.c

• Lines: 131
• Date: Sat Mar 30 17:46:01 1996
• Orig file: v1.3.93/linux/fs/affs/amigaffs.c
• Orig date: Thu Jan 1 02:00:00 1970

diff -u --recursive --new-file v1.3.93/linux/fs/affs/amigaffs.c linux/fs/affs/amigaffs.c
@@ -0,0 +1,130 @@
+/*
+ *  linux/fs/affs/amigaffs.c
+ *
+ *  (C) 1993  Ray Burr - Amiga FFS filesystem.
+ *
+ */
+
+#include <linux/fs.h>
+#include <linux/affs_fs.h>
+#include <linux/mm.h>
+
+#include "amigaffs.h"
+
+/*
+ * Functions for accessing Amiga-FFS structures.
+ *
+ */
+
+/* Get key entry number ENTRY_POS from the header block pointed to
+   by DATA.  If ENTRY_POS is invalid, -1 is returned.  This is
+   used to get entries from file and directory headers as well
+   as extension and root blocks.  In the current FFS specs, these
+   tables are defined to be the same size in all of these. */
+
+int affs_get_key_entry (int bsize, void *data, int entry_pos)
+{
+	struct dir_front *dir_front = (struct dir_front *)data;
+	int key, hash_table_size;
+
+	hash_table_size = MIDBLOCK_LONGS (bsize);
+	key = 0;
+	if (entry_pos >= 0 && entry_pos < hash_table_size)
+		key = swap_long (dir_front->hash_table[entry_pos]);
+
+	return key;
+}
+
+/* Find the next used hash entry at or after *HASH_POS in a directory's hash
+   table.  *HASH_POS is assigned that entry's number.  DIR_DATA points to
+   the directory header block in memory.  If there are no more entries,
+   0 is returned.  Otherwise, the key number in the next used hash slot
+   is returned. */
+
+int affs_find_next_hash_entry (int bsize, void *dir_data, int *hash_pos)
+{
+	struct dir_front *dir_front = (struct dir_front *)dir_data;
+	int i, hash_table_size;
+
+	hash_table_size = MIDBLOCK_LONGS (bsize);
+	if (*hash_pos < 0 || *hash_pos >= hash_table_size)
+		return -1;
+	for (i = *hash_pos; i < hash_table_size; i++)
+		if (dir_front->hash_table[i] != 0)
+			break;
+	if (i == hash_table_size)
+		return 0;
+	*hash_pos = i;
+	return swap_long (dir_front->hash_table[i]);
+}
+
+/* Get the hash_chain (next file header key in hash chain) entry from a
+   file header block in memory pointed to by FH_DATA. */
+
+int affs_get_fh_hash_link (int bsize, void *fh_data)
+{
+	struct file_end *file_end;
+	int key;
+
+	file_end = GET_END_PTR (struct file_end, fh_data, bsize);
+	key = swap_long (file_end->hash_chain);
+	return key;
+}
+
+/* Set *NAME to point to the file name in a file header block in memory
+   pointed to by FH_DATA.  The length of the name is returned. */
+
+int affs_get_file_name (int bsize, void *fh_data, char **name)
+{
+	struct file_end *file_end;
+
+	file_end = GET_END_PTR (struct file_end, fh_data, bsize);
+	if (file_end->file_name[0] == 0
+	    || file_end->file_name[0] > 30) {
+		printk ("affs_get_file_name: OOPS! bad filename\n");
+		printk ("  file_end->file_name[0] = %d\n",
+			file_end->file_name[0]);
+		*name = "***BAD_FILE***";
+		return 14;
+        }
+	*name = (char *) &file_end->file_name[1];
+        return file_end->file_name[0];
+}
+
+/* Get the key number of the first extention block for the file
+   header pointed to by FH_DATA. */
+
+int affs_get_extension (int bsize, void *fh_data)
+{
+	struct file_end *file_end;
+	int key;
+
+	file_end = GET_END_PTR (struct file_end, fh_data, bsize);
+	key = swap_long (file_end->extension);
+	return key;
+}
+
+/* Checksum a block, do various consistency checks and optionally return
+   the blocks type number.  DATA points to the block.  If their pointers
+   are non-null, *PTYPE and *STYPE are set to the primary and secondary
+   block types respectively.  Returns non-zero if the block is not
+   consistent. */
+
+int affs_checksum_block (int bsize, void *data, int *ptype, int *stype)
+{
+	if (ptype)
+		*ptype = swap_long (((long *) data)[0]);
+	if (stype)
+		*stype = swap_long (((long *) data)[bsize / 4 - 1]);
+	return 0;
+}
+
+static struct file_system_type affs_fs_type = {
+        affs_read_super, "affs", 1, NULL
+};
+
+int init_affs_fs(void)
+{
+        return register_filesystem(&affs_fs_type);
+}
+