67  * When we search a directory the blocks containing directory entries are
68  * read and examined.  The directory entries contain information that would
70  * a directory's contents may also be in memory resident denodes (sort of
72  * process is modifying a directory.  To prevent one process from accessing
73  * incompletely modified directory information we depend upon being the
74  * sole owner of a directory block.  bread/brelse provide this service.
75  * This being the case, when a process modifies a directory it must first
76  * acquire the disk block that contains the directory entry to be modified.
78  * out to disk.  This way disk blocks containing directory entries and in
99 	int isadir;		/* ~0 if found direntry is a directory	 */  in msdosfs_lookup()
133 	 * Check accessibility of directory.  in msdosfs_lookup()
141 	 * We now have a segment name to search for, and a directory to search.  in msdosfs_lookup()
143 	 * Before tediously performing a linear scan of the directory,  in msdosfs_lookup()
144 	 * check the name cache to see if the directory/name pair  in msdosfs_lookup()
151 	 * If they are going after the . or .. entry in the root directory,  in msdosfs_lookup()
153 	 * directory.  So, we fake it. deget() is in on this scam too.  in msdosfs_lookup()
161 		printf("msdosfs_lookup(): looking for . or .. in root directory\n");  in msdosfs_lookup()
201 	 * We want to search the directory pointed to by vdp for the name  in msdosfs_lookup()
223 	 * directory.  Note that the root directory is different from all  in msdosfs_lookup()
226 	 * little differently. The root directory starts at "cluster" 0.  in msdosfs_lookup()
250 			 * remainder of the directory has never been used,  in msdosfs_lookup()
292 				 * the root directory).  in msdosfs_lookup()
313 				 * Remember where this directory  in msdosfs_lookup()
321 					 * directory entries, reuse them as  in msdosfs_lookup()
327 					 * Long name directory entries not  in msdosfs_lookup()
329 					 * dos directory entry.  in msdosfs_lookup()
337 		 * Release the buffer holding the directory cluster just  in msdosfs_lookup()
363 	 * the pathname and the directory hasn't been removed.  in msdosfs_lookup()
375 		 * creation of files in the directory.  in msdosfs_lookup()
381 		 * Return an indication of where the new directory  in msdosfs_lookup()
388 		 * We return with the directory locked, so that  in msdosfs_lookup()
393 		 * the (locked) directory inode in ndp->ni_dvp.  in msdosfs_lookup()
397 		 * NB - if the directory is unlocked, then this  in msdosfs_lookup()
416 	 * NOTE:  We still have the buffer with matched directory entry at  in msdosfs_lookup()
453 	 * entry of the filesystems root directory.  isadir and scn were  in msdosfs_lookup()
463 	 * the directory (in ndp->ni_dvp), otherwise we go  in msdosfs_lookup()
474 		 * Write access to directory required to delete files.  in msdosfs_lookup()
482 		 * Save directory inode pointer in ndp->ni_dvp for dirremove().  in msdosfs_lookup()
501 	 * information required to rewrite the present directory  in msdosfs_lookup()
502 	 * Must get inode of directory entry to verify it's a  in msdosfs_lookup()
503 	 * regular file, or empty directory.  in msdosfs_lookup()
532 	 * directory because we may need it again if a symbolic link  in msdosfs_lookup()
533 	 * is relative to the current directory.  Instead we save it  in msdosfs_lookup()
535 	 * the directory to insure that the inode will not be removed  in msdosfs_lookup()
537 	 * inodes from the root, moving down the directory tree. Thus  in msdosfs_lookup()
539 	 * parent directory before getting the requested directory.  in msdosfs_lookup()
547 	 * that point backwards in the directory structure.  in msdosfs_lookup()
588  * dep  - directory entry to copy into the directory
589  * ddep - directory to add to
590  * depp - return the address of the denode for the created directory entry
612 	 * If no space left in the directory then allocate another cluster  in createde()
614 	 * to this.  That is, if the root directory has no more space it  in createde()
616 	 * to extend the root directory.  We just return an error in that  in createde()
630 		 * Update the size of the directory  in createde()
636 	 * We just read in the cluster with space.  Copy the new directory  in createde()
715  * Be sure a directory is empty except for "." and "..". Return 1 if empty,
730 	 * Since the filesize field in directory entries for a directory is  in dosdirempty()
731 	 * zero, we just have to feel our way through the directory until  in dosdirempty()
754 				 * directory, so we can just return that it  in dosdirempty()
763 				 * directory mean it is not empty.  in dosdirempty()
782  * Check to see if the directory described by target is in some
870 		printf("doscheckpath(): .. not a directory?\n");  in doscheckpath()
877  * Read in the disk block containing the directory entry (dirclu, dirofs)
879  * directory entry within the block.
905  * Read in the disk block containing the directory entry dep came from and
906  * return the address of the buf header, and the address of the directory
918  * Remove a directory entry. At this point the file represented by the
919  * directory entry to be removed is still full length until noone has it
925  * pdep - directory where the entry is removed