X-Git-Url: http://erislabs.net/gitweb/?a=blobdiff_plain;f=lib%2Ffts_.h;h=0e2d505aff98e53bd9362fb91bc478c40e20bb5d;hb=6a9b156fdf9c71c0bbc8bb0b3aa0262df5674dda;hp=954ba569ba01407f57b678c6e01d81c304008589;hpb=c2546905a0f3958439581290d150c9ae4ae52a50;p=gnulib.git
diff --git a/lib/fts_.h b/lib/fts_.h
index 954ba569b..0e2d505af 100644
--- a/lib/fts_.h
+++ b/lib/fts_.h
@@ -1,11 +1,11 @@
/* Traverse a file hierarchy.
- Copyright (C) 2004, 2005 Free Software Foundation, Inc.
+ Copyright (C) 2004-2009 Free Software Foundation, Inc.
- This program is free software; you can redistribute it and/or modify
+ 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
- the Free Software Foundation; either version 2, or (at your option)
- any later version.
+ the Free Software Foundation; either version 3 of the License, or
+ (at your option) any later version.
This program is distributed in the hope that it will be useful,
but WITHOUT ANY WARRANTY; without even the implied warranty of
@@ -13,8 +13,7 @@
GNU General Public License for more details.
You should have received a copy of the GNU General Public License
- along with this program; if not, write to the Free Software Foundation,
- Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA. */
+ along with this program. If not, see . */
/*
* Copyright (c) 1989, 1993
@@ -52,7 +51,6 @@
# ifdef _LIBC
# include
-# define _LGPL_PACKAGE 1
# else
# undef __THROW
# define __THROW
@@ -65,16 +63,19 @@
# include
# include
# include
+# include "i-ring.h"
typedef struct {
struct _ftsent *fts_cur; /* current node */
struct _ftsent *fts_child; /* linked list of children */
struct _ftsent **fts_array; /* sort array */
dev_t fts_dev; /* starting device # */
- char *fts_path; /* path for this descent */
+ 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 */
@@ -88,7 +89,8 @@ typedef struct {
# define FTS_WHITEOUT 0x0080 /* return whiteout information */
/* There are two ways to detect cycles.
- The lazy way, with which one may process a directory that is a
+ The lazy way (which works only with FTS_PHYSICAL),
+ with which one may process a directory that is a
part of the cycle several times before detecting the cycle.
The `tight' way, whereby fts uses more memory (proportional
to number of `active' directories, aka distance from root
@@ -96,16 +98,61 @@ typedef struct {
to detect any cycle right away. For example, du must use
this option to avoid counting disk space in a cycle multiple
times, but chown -R need not.
- The default is to use the constant-memory lazy way. */
+ The default is to use the constant-memory lazy way, when possible
+ (see below).
+
+ However, with FTS_LOGICAL (when following symlinks, e.g., chown -L)
+ using lazy cycle detection is inadequate. For example, traversing
+ a directory containing a symbolic link to a peer directory, it is
+ possible to encounter the same directory twice even though there
+ is no cycle:
+ dir
+ ...
+ slink -> dir
+ So, when FTS_LOGICAL is selected, we have to use a different
+ 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
+
+ /* Historically, for each directory that fts initially encounters, it would
+ open it, read all entries, and stat each entry, storing the results, and
+ then it would process the first entry. But that behavior is bad for
+ locality of reference, and also causes trouble with inode-simulating
+ file systems like FAT, CIFS, FUSE-based ones, etc., when entries from
+ their name/inode cache are flushed too early.
+ Use this flag to make fts_open and fts_read defer the stat/lstat/fststat
+ of each entry until it is actually processed. However, note that if you
+ use this option and also specify a comparison function, that function may
+ not examine any data via fts_statp. However, when fts_statp->st_mode is
+ nonzero, the S_IFMT type bits are valid, with mapped dirent.d_type data.
+ Of course, that happens only on file systems that provide useful
+ dirent.d_type data. */
+# define FTS_DEFER_STAT 0x0400
+
+# define FTS_OPTIONMASK 0x07ff /* valid user option mask */
# define FTS_NAMEONLY 0x1000 /* (private) child names only */
# define FTS_STOP 0x2000 /* (private) unrecoverable error */
int fts_options; /* fts_open options, global flags */
-# if !_LGPL_PACKAGE
+# if GNULIB_FTS
+ /* Map a directory's device number to a boolean. The boolean is
+ true if for that file system (type determined by a single fstatfs
+ call per FS) st_nlink can be used to calculate the number of
+ sub-directory entries in a directory.
+ Using this table is an optimization that permits us to look up
+ file system type on a per-inode basis at the minimal cost of
+ calling fstatfs only once per traversed device. */
+ struct hash_table *fts_leaf_optimization_works_ht;
+
union {
/* This data structure is used if FTS_TIGHT_CYCLE_CHECK is
specified. It records the directories between a starting
@@ -121,12 +168,18 @@ typedef struct {
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
+ /* A stack of the file descriptors corresponding to the
+ most-recently traversed parent directories.
+ Currently used only in FTS_CWDFD mode. */
+ I_ring fts_fd_ring;
} FTS;
typedef struct _ftsent {
@@ -135,8 +188,8 @@ typedef struct _ftsent {
struct _ftsent *fts_link; /* next file in directory */
long fts_number; /* local numeric value */
void *fts_pointer; /* local address value */
- char *fts_accpath; /* access path */
- char *fts_path; /* root path; == fts_fts->fts_path */
+ char *fts_accpath; /* access file name */
+ char *fts_path; /* root name; == fts_fts->fts_path */
int fts_errno; /* errno for this node */
int fts_symfd; /* fd for symlink */
size_t fts_pathlen; /* strlen(fts_path) */
@@ -148,6 +201,7 @@ typedef struct _ftsent {
ptrdiff_t fts_level; /* depth (-1 to N) */
size_t fts_namelen; /* strlen(fts_name) */
+ nlink_t fts_n_dirs_remaining; /* count down from st_nlink */
# define FTS_D 1 /* preorder directory */
# define FTS_DC 2 /* directory that causes cycles */
@@ -179,12 +233,30 @@ typedef struct _ftsent {
char fts_name[1]; /* file name */
} FTSENT;
+#ifndef __GNUC_PREREQ
+# if defined __GNUC__ && defined __GNUC_MINOR__
+# define __GNUC_PREREQ(maj, min) \
+ ((__GNUC__ << 16) + __GNUC_MINOR__ >= ((maj) << 16) + (min))
+# else
+# define __GNUC_PREREQ(maj, min) 0
+# endif
+#endif
+
+#if __GNUC_PREREQ (3,4)
+# undef __attribute_warn_unused_result__
+# define __attribute_warn_unused_result__ \
+ __attribute__ ((__warn_unused_result__))
+#else
+# define __attribute_warn_unused_result__ /* empty */
+#endif
+
__BEGIN_DECLS
-FTSENT *fts_children (FTS *, int) __THROW;
-int fts_close (FTS *) __THROW;
+FTSENT *fts_children (FTS *, int) __THROW __attribute_warn_unused_result__;
+int fts_close (FTS *) __THROW __attribute_warn_unused_result__;
FTS *fts_open (char * const *, int,
- int (*)(const FTSENT **, const FTSENT **)) __THROW;
-FTSENT *fts_read (FTS *) __THROW;
+ int (*)(const FTSENT **, const FTSENT **))
+ __THROW __attribute_warn_unused_result__;
+FTSENT *fts_read (FTS *) __THROW __attribute_warn_unused_result__;
int fts_set (FTS *, FTSENT *, int) __THROW;
__END_DECLS