CC-tea/coreutils
1
0
Fork 0
mirror of git://git.sv.gnu.org/coreutils.git synced 2026-07-26 02:30:35 +02:00
Code Issues Projects Releases Wiki Activity

Restore the parts of fts that were removed on 2006-01-17, so that

Browse Source 
it's easier for legacy applications designed for the version
of fts in glibc or BSD to convert to this more robust version.
Add a new mode, FTS_CWDFD, by which to enable the improved
(openat- based -- aka no-chdir) semantics.

* fts_.h (FTS_CWDFD): Define.  Callers must use this fts_open
option to enable the more robust behavior.
(FTS_OPTIONMASK): Widen accordingly.
* fts.c: Restore removed code, reverting the default behavior.
This commit is contained in:
Jim Meyering
2006-05-15 10:00:16 +00:00
parent 48138763f0
commit 7729ee5e68
2 changed files with 122 additions and 35 deletions
Download Patch File Download Diff File Expand all files Collapse all files
lib/fts.c
+111 -34
View File
@@ -105,6 +105,8 @@ static char sccsid[] = "@(#)fts.c 8.6 (Berkeley) 8/14/94";
# define close __close
# undef closedir
# define closedir __closedir
# undef fchdir
# define fchdir __fchdir
# undef open
# define open __open
# undef opendir
@@ -178,8 +180,14 @@ static void free_dir (FTS *fts) {}
#define ISSET(opt) (sp->fts_options & (opt))
#define SET(opt) (sp->fts_options |= (opt))
#define FCHDIR(sp, fd) (!ISSET(FTS_NOCHDIR) \
&& (cwd_advance_fd (sp, fd), 0))
#define RESTORE_INITIAL_CWD(sp) FCHDIR (sp, (ISSET (FTS_CWDFD) \
? AT_FDCWD \
: sp->fts_rfd))
#define FCHDIR(sp, fd) (!ISSET(FTS_NOCHDIR) \
&& (ISSET(FTS_CWDFD) \
? (cwd_advance_fd (sp, fd), 0) \
: fchdir(fd)))
/* fts_build flags */
@@ -262,7 +270,9 @@ static inline int
internal_function
diropen (FTS const *sp, char const *dir)
{
return diropen_fd (sp->fts_cwd_fd, dir);
return (ISSET(FTS_CWDFD)
? diropen_fd (sp->fts_cwd_fd, dir)
: open (dir, O_RDONLY | O_DIRECTORY | O_NOCTTY | O_NONBLOCK));
}
FTS *
@@ -282,6 +292,10 @@ fts_open (char * const *argv,
__set_errno (EINVAL);
return (NULL);
}
if ((options & FTS_NOCHDIR) && (options & FTS_CWDFD)) {
__set_errno (EINVAL);
return (NULL);
}
/* Allocate/initialize the stream */
if ((sp = malloc(sizeof(FTS))) == NULL)
@@ -291,12 +305,14 @@ fts_open (char * const *argv,
sp->fts_options = options;
/* Logical walks turn on NOCHDIR; symbolic links are too hard. */
if (ISSET(FTS_LOGICAL))
if (ISSET(FTS_LOGICAL)) {
SET(FTS_NOCHDIR);
CLR(FTS_CWDFD);
}
/* Initialize fts_cwd_fd. */
sp->fts_cwd_fd = AT_FDCWD;
if ( ! ISSET(FTS_NOCHDIR) && ! HAVE_OPENAT_SUPPORT)
if ( ISSET(FTS_CWDFD) && ! HAVE_OPENAT_SUPPORT)
{
/* While it isn't technically necessary to open "." this
early, doing it here saves us the trouble of ensuring
@@ -319,7 +335,7 @@ fts_open (char * const *argv,
if ( openat_needs_fchdir ())
{
SET(FTS_NOCHDIR);
sp->fts_cwd_fd = -1;
CLR(FTS_CWDFD);
}
}
else
@@ -399,6 +415,17 @@ fts_open (char * const *argv,
if (! setup_dir (sp))
goto mem3;
/*
* If using chdir(2), grab a file descriptor pointing to dot to ensure
* that we can get back here; this could be avoided for some file names,
* but almost certainly not worth the effort. Slashes, symbolic links,
* and ".." are all fairly nasty problems. Note, if we can't get the
* descriptor we run anyway, just more slowly.
*/
if (!ISSET(FTS_NOCHDIR) && !ISSET(FTS_CWDFD)
&& (sp->fts_rfd = diropen (sp, ".")) < 0)
SET(FTS_NOCHDIR);
return (sp);
mem3: fts_lfree(root);
@@ -460,8 +487,18 @@ fts_close (FTS *sp)
free(sp->fts_array);
free(sp->fts_path);
if (0 <= sp->fts_cwd_fd)
close (sp->fts_cwd_fd);
if (ISSET(FTS_CWDFD))
{
if (0 <= sp->fts_cwd_fd)
close (sp->fts_cwd_fd);
}
else if (!ISSET(FTS_NOCHDIR))
{
/* Return to original directory, save errno if necessary. */
if (fchdir(sp->fts_rfd))
saved_errno = errno;
close(sp->fts_rfd);
}
free_dir (sp);
@@ -601,7 +638,11 @@ next: tmp = p;
* root.
*/
if (p->fts_level == FTS_ROOTLEVEL) {
FCHDIR(sp, AT_FDCWD);
if (RESTORE_INITIAL_CWD(sp)) {
SET(FTS_STOP);
sp->fts_cur = p;
return (NULL);
}
fts_load(sp, p);
goto check_for_dir;
}
@@ -660,15 +701,24 @@ check_for_dir:
sp->fts_path[p->fts_pathlen] = '\0';
/*
* Return to the parent directory. If at a root node, just set
* sp->fts_cwd_fd to AT_FDCWD. If we came through a symlink,
* Return to the parent directory. If at a root node, restore
* the initial working directory. If we came through a symlink,
* go back through the file descriptor. Otherwise, move up
* one level, via "..".
*/
if (p->fts_level == FTS_ROOTLEVEL) {
FCHDIR(sp, AT_FDCWD);
if (RESTORE_INITIAL_CWD(sp)) {
p->fts_errno = errno;
SET(FTS_STOP);
}
} else if (p->fts_flags & FTS_SYMFOLLOW) {
FCHDIR(sp, p->fts_symfd);
if (FCHDIR(sp, p->fts_symfd)) {
int saved_errno = errno;
(void)close(p->fts_symfd);
__set_errno (saved_errno);
p->fts_errno = errno;
SET(FTS_STOP);
}
(void)close(p->fts_symfd);
} else if (!(p->fts_flags & FTS_DONTCHDIR) &&
fts_safe_changedir(sp, p->fts_parent, -1, "..")) {
@@ -761,7 +811,22 @@ fts_children (register FTS *sp, int instr)
if ((fd = diropen (sp, ".")) < 0)
return (sp->fts_child = NULL);
sp->fts_child = fts_build(sp, instr);
cwd_advance_fd (sp, fd);
if (ISSET(FTS_CWDFD))
{
cwd_advance_fd (sp, fd);
}
else
{
if (fchdir(fd))
{
// FIXME: save/restore is a fix over prev. version
int saved_errno = errno;
close (fd);
__set_errno (saved_errno);
return NULL;
}
close (fd);
}
return (sp->fts_child);
}
@@ -812,9 +877,9 @@ fts_build (register FTS *sp, int type)
oflag = DTF_HIDEW|DTF_NODUP|DTF_REWIND;
#else
# define __opendir2(file, flag) \
(ISSET(FTS_NOCHDIR) \
? opendir(file) \
: opendirat(sp->fts_cwd_fd, file))
( ! ISSET(FTS_NOCHDIR) && ISSET(FTS_CWDFD) \
? opendirat(sp->fts_cwd_fd, file) \
: opendir(file))
#endif
if ((dirp = __opendir2(cur->fts_accpath, oflag)) == NULL) {
if (type == BREAD) {
@@ -858,14 +923,16 @@ fts_build (register FTS *sp, int type)
* checking FTS_NS on the returned nodes.
*/
if (nlinks || type == BREAD) {
int dir_fd = dup (dirfd(dirp));
int dir_fd = dirfd(dirp);
if (ISSET(FTS_CWDFD) && 0 <= dir_fd)
dir_fd = dup (dir_fd);
if (dir_fd < 0 || fts_safe_changedir(sp, cur, dir_fd, NULL)) {
if (nlinks && type == BREAD)
cur->fts_errno = errno;
cur->fts_flags |= FTS_DONTCHDIR;
descend = false;
closedir(dirp);
if (0 <= dir_fd)
if (ISSET(FTS_CWDFD) && 0 <= dir_fd)
close (dir_fd);
dirp = NULL;
} else
@@ -1008,9 +1075,9 @@ mem1: saved_errno = errno;
* can't get back, we're done.
*/
if (descend && (type == BCHILD || !nitems) &&
(cur->fts_level == FTS_ROOTLEVEL ?
FCHDIR(sp, AT_FDCWD) :
fts_safe_changedir(sp, cur->fts_parent, -1, ".."))) {
(cur->fts_level == FTS_ROOTLEVEL
? RESTORE_INITIAL_CWD(sp)
: fts_safe_changedir(sp, cur->fts_parent, -1, ".."))) {
cur->fts_info = FTS_ERR;
SET(FTS_STOP);
fts_lfree(head);
@@ -1364,30 +1431,40 @@ static int
internal_function
fts_safe_changedir (FTS *sp, FTSENT *p, int fd, char const *dir)
{
int ret;
struct stat sb;
int newfd = fd;
if (ISSET(FTS_NOCHDIR)) {
if (0 <= fd)
if (ISSET(FTS_CWDFD) && 0 <= fd)
close (fd);
return (0);
}
if (fd < 0 && (newfd = diropen (sp, dir)) < 0)
return (-1);
if (fstat(newfd, &sb)) {
if (0 <= fd) {
int saved_errno = errno;
close (fd);
errno = saved_errno;
}
return -1;
ret = -1;
goto bail;
}
if (p->fts_statp->st_dev != sb.st_dev
|| p->fts_statp->st_ino != sb.st_ino) {
if (0 <= fd)
close (fd);
__set_errno (ENOENT); /* disinformation */
return -1;
ret = -1;
goto bail;
}
cwd_advance_fd (sp, newfd);
return 0;
if (ISSET(FTS_CWDFD))
{
cwd_advance_fd (sp, newfd);
return 0;
}
ret = fchdir(newfd);
bail:
if (fd < 0)
{
int oerrno = errno;
(void)close(newfd);
__set_errno (oerrno);
}
return (ret);
}
lib/fts_.h
+11 -1
View File
@@ -72,6 +72,7 @@ typedef struct {
struct _ftsent **fts_array; /* sort array */
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) */
@@ -113,7 +114,16 @@ typedef struct {
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 */