Initial Import from SVN

sys/include/dir.h

@@ -0,0 +1,105 @@
+/*
+ * Copyright (c) 1986 Regents of the University of California.
+ * All rights reserved.  The Berkeley software License Agreement
+ * specifies the terms and conditions for redistribution.
+ */
+#ifndef	_DIR_
+#define	_DIR_
+
+#ifndef MAXNAMLEN
+#define MAXNAMLEN	63
+#endif
+
+#define DIRBLKSIZ	1024
+
+/*
+ * inode numbers are ino_t rather than u_long now.  before, when v7direct
+ * was used for the kernel, inode numbers were u_short/ino_t anyways, and since
+ * everything had to be recompiled when the fs structure was changed it seemed
+ * like a good idea to change the "real direct structure".  SMS
+*/
+
+struct	direct {
+	ino_t	d_ino;			/* inode number of entry */
+	u_short	d_reclen;		/* length of this record */
+	u_short	d_namlen;		/* length of string in d_name */
+	char	d_name[MAXNAMLEN+1];	/* name must be no longer than this */
+};
+
+/*
+ * A directory consists of some number of blocks of DIRBLKSIZ
+ * bytes, where DIRBLKSIZ is chosen such that it can be transferred
+ * to disk in a single atomic operation (e.g. 512 bytes on most machines).
+ *
+ * Each DIRBLKSIZ byte block contains some number of directory entry
+ * structures, which are of variable length.  Each directory entry has
+ * a struct direct at the front of it, containing its inode number,
+ * the length of the entry, and the length of the name contained in
+ * the entry.  These are followed by the name padded to a 4 byte boundary
+ * with null bytes.  All names are guaranteed null terminated.
+ * The maximum length of a name in a directory is MAXNAMLEN.
+ *
+ * The macro DIRSIZ(dp) gives the amount of space required to represent
+ * a directory entry.  Free space in a directory is represented by
+ * entries which have dp->d_reclen > DIRSIZ(dp).  All DIRBLKSIZ bytes
+ * in a directory block are claimed by the directory entries.  This
+ * usually results in the last entry in a directory having a large
+ * dp->d_reclen.  When entries are deleted from a directory, the
+ * space is returned to the previous entry in the same directory
+ * block by increasing its dp->d_reclen.  If the first entry of
+ * a directory block is free, then its dp->d_ino is set to 0.
+ * Entries other than the first in a directory do not normally have
+ * dp->d_ino set to 0.
+ */
+
+#undef DIRSIZ
+#define DIRSIZ(dp) \
+    ((((sizeof (struct direct) - (MAXNAMLEN+1)) + (dp)->d_namlen+1) + 3) &~ 3)
+
+/*
+ * Definitions for library routines operating on directories.
+ */
+typedef struct _dirdesc {
+	int	dd_fd;
+	long	dd_loc;
+	long	dd_size;
+	char	dd_buf[DIRBLKSIZ];
+	struct direct	dd_cur;
+} DIR;
+
+#ifndef NULL
+#define NULL 0
+#endif
+
+#ifndef	KERNEL
+
+extern	DIR *opendir (const char *);
+extern	struct direct *readdir (DIR *);
+extern	long telldir (DIR *);
+extern	void seekdir (DIR *, long);
+extern	void closedir (DIR *);
+
+#define rewinddir(dirp)	seekdir ((dirp), (long)0)
+#define dirfd(dirp)	((dirp)->dd_fd)
+
+#endif /* !KERNEL */
+
+/*
+ * Template for manipulating directories.
+ * Should use struct direct's, but the name field
+ * is MAXNAMLEN - 1, and this just won't do.
+ */
+#define dotdot_ino	dtdt_ino
+#define dotdot_reclen	dtdt_rec
+#define dotdot_name	dtdt_name
+struct dirtemplate {
+	ino_t	dot_ino;
+	u_short	dot_reclen;
+	u_short	dot_namlen;
+	char	dot_name[4];		/* must be multiple of 4 */
+	ino_t	dotdot_ino;
+	u_short	dotdot_reclen;
+	u_short	dotdot_namlen;
+	char	dotdot_name[4];		/* ditto */
+};
+#endif /* _DIR_ */