diff lib/fts_.h @ 7151:43e3888c56c4

Update from coreutils. * lib/__fpending.h: Add copyright notice. * lib/fprintftime.h: Likewise. * lib/savedir.c: Use (C) in copyright notice. * lib/savedir.h: Likewise. 2006-08-15 Jim Meyering <jim@meyering.net> * lib/at-func.c: New file, with the logic of all emulated at-functions. * lib/openat-priv.h: Include <errno.h> and define ENOSYS, in support of the EXPECTED_ERRNO macro. * lib/openat.c (fstatat, unlinkat, fchownat): Remove function definitions. Instead, define the appropriate symbols and include "at-func.c". * lib/mkdirat.c (mkdirat): Likewise. * lib/fchmodat.c (fchmodat): Likewise. (ENOSYS): Remove definition. * lib/openat.c: Don't include <errno.h>, now that "openat-priv.h" does it. Don't include "unistd--.h" -- it wasn't ever used. 2006-01-17 Jim Meyering <jim@meyering.net> Rewrite fts.c not to change the current working directory, by using openat, fstatat, fdopendir, etc.. * lib/fts.c [! _LIBC]: Include "openat.h" and "unistd--.h". (HAVE_OPENAT_SUPPORT): Define. [_LIBC] (fchdir): Don't undef or define; no longer used. (FCHDIR): Define in terms of cwd_advance_fd rather than fchdir. Now, this `function' always succeeds, and consumes its file descriptor parameter -- so callers must not close such FDs. Update callers. (diropen_fd, opendirat, cwd_advance_fd): New functions. (diropen): Add parameter, SP. Adjust all callers. Implement using diropen_fd, rather than open. (fts_open): Initialize new member, fts_cwd_fd. Remove fts_rft-setting code. (fts_close): Close fts_cwd_fd, if necessary. (__opendir2): Define in terms of opendir or opendirat, depending on whether the FST_NOCHDIR flag is set. (fts_build): Since fts_safe_changedir consumes its FD, and since this code must do `closedir(dirp)', dup the dirfd(dirp) argument, and close the dup'd file descriptor upon failure. (fts_stat): Use fstatat(...AT_SYMLINK_NOFOLLOW) in place of lstat. (fts_safe_changedir): Tweak semantics to reflect that this function now calls cwd_advance_fd and hence consumes its FD argument. * lib/fts_.h [struct FTS] (fts_cwd_fd): New member. [struct FTS] (fts_rft): Remove now-unused member. [struct FTS] (fts_cycle.state): Improve comment. * lib/openat.c (openat_needs_fchdir): New function. * lib/openat.h (openat_needs_fchdir): Declare it. 2006-08-15 Jim Meyering <jim@meyering.net> * m4/openat.m4 (gl_FUNC_OPENAT): Add at-func.c via AC_LIBSOURCES. 2006-01-17 Jim Meyering <jim@meyering.net> * m4/fts.m4 (gl_FUNC_FTS_CORE): Depend on gl_FUNC_OPENAT. 2006-01-11 Jim Meyering <jim@meyering.net> * m4/openat.m4 (gl_FUNC_OPENAT): Require and compile fchmodat.c. Check for the lchmod function.
author Paul Eggert <eggert@cs.ucla.edu>
date Thu, 17 Aug 2006 20:34:21 +0000
parents a166800910b5
children 26914593f079
line wrap: on
line diff
--- a/lib/fts_.h
+++ b/lib/fts_.h
@@ -1,6 +1,6 @@
 /* Traverse a file hierarchy.
 
-   Copyright (C) 2004, 2005 Free Software Foundation, Inc.
+   Copyright (C) 2004, 2005, 2006 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
@@ -73,8 +73,10 @@
 	dev_t fts_dev;			/* starting device # */
 	char *fts_path;			/* file name for this descent */
 	int fts_rfd;			/* fd for root */
+	int fts_cwd_fd;			/* the file descriptor on which the
+					   virtual cwd is open, or AT_FDCWD */
 	size_t fts_pathlen;		/* sizeof(path) */
-	size_t fts_nitems;			/* elements in the sort array */
+	size_t fts_nitems;		/* elements in the sort array */
 	int (*fts_compar) (struct _ftsent const **, struct _ftsent const **);
 					/* compare fn */
 
@@ -112,7 +114,16 @@
      mode of cycle detection: FTS_TIGHT_CYCLE_CHECK.  */
 # define FTS_TIGHT_CYCLE_CHECK	0x0100
 
-# define FTS_OPTIONMASK	0x01ff		/* valid user option mask */
+  /* Use this flag to enable semantics with which the parent
+     application may be made both more efficient and more robust.
+     Whereas the default is to visit each directory in a recursive
+     traversal (via chdir), using this flag makes it so the initial
+     working directory is never changed.  Instead, these functions
+     perform the traversal via a virtual working directory, maintained
+     through the file descriptor member, fts_cwd_fd.  */
+# define FTS_CWDFD		0x0200
+
+# define FTS_OPTIONMASK	0x03ff		/* valid user option mask */
 
 # define FTS_NAMEONLY	0x1000		/* (private) child names only */
 # define FTS_STOP	0x2000		/* (private) unrecoverable error */
@@ -134,9 +145,10 @@
 		   of thousands.  */
 		struct hash_table *ht;
 
-		/* This data structure uses lazy checking, as done by rm via
-	           cycle-check.c.  It's the default, but it's not appropriate
-	           for programs like du.  */
+		/* FIXME: rename these two members to have the fts_ prefix */
+		/* This data structure uses a lazy cycle-detection algorithm,
+		   as done by rm via cycle-check.c.  It's the default,
+		   but it's not appropriate for programs like du.  */
 		struct cycle_check_state *state;
 	} fts_cycle;
 # endif