X-Git-Url: http://erislabs.net/gitweb/?a=blobdiff_plain;ds=sidebyside;f=lib%2Fchdir-long.c;h=599d14157a9138823f17267f031c504547ad65a9;hb=141e296490e776bb758ee88616dae79aed0b4006;hp=50cae34b5677835958e8cb61c7907c7789260749;hpb=efc9686904177e6644b5528c4703f378daaee0b0;p=gnulib.git
diff --git a/lib/chdir-long.c b/lib/chdir-long.c
index 50cae34b5..599d14157 100644
--- a/lib/chdir-long.c
+++ b/lib/chdir-long.c
@@ -1,10 +1,10 @@
/* provide a chdir function that tries not to fail due to ENAMETOOLONG
- Copyright (C) 2004, 2005, 2006 Free Software Foundation, Inc.
+ Copyright (C) 2004-2012 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
@@ -12,32 +12,31 @@
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 . */
/* written by Jim Meyering */
-#ifdef HAVE_CONFIG_H
-# include
-#endif
+#include
#include "chdir-long.h"
+#include
+#include
#include
#include
#include
#include
-#include
#include
-#include
-
-#include "memrchr.h"
-#include "openat.h"
#ifndef PATH_MAX
# error "compile this file only if your system defines PATH_MAX"
#endif
+/* The results of openat() in this file are not leaked to any
+ single-threaded code that could use stdio.
+ FIXME - if the kernel ever adds support for multi-thread safety for
+ avoiding standard fds, then we should use openat_safer. */
+
struct cd_buf
{
int fd;
@@ -73,7 +72,7 @@ static int
cdb_advance_fd (struct cd_buf *cdb, char const *dir)
{
int new_fd = openat (cdb->fd, dir,
- O_RDONLY | O_DIRECTORY | O_NOCTTY | O_NONBLOCK);
+ O_SEARCH | O_DIRECTORY | O_NOCTTY | O_NONBLOCK);
if (new_fd < 0)
return -1;
@@ -84,7 +83,7 @@ cdb_advance_fd (struct cd_buf *cdb, char const *dir)
}
/* Return a pointer to the first non-slash in S. */
-static inline char *
+static inline char * _GL_ATTRIBUTE_PURE
find_non_slash (char const *s)
{
size_t n_slash = strspn (s, "/");
@@ -97,7 +96,7 @@ find_non_slash (char const *s)
name. It handles an arbitrarily long directory name by operating
on manageable portions of the name. On systems without the openat
syscall, this means changing the working directory to more and more
- `distant' points along the long directory name and then restoring
+ "distant" points along the long directory name and then restoring
the working directory. If any of those attempts to save or restore
the working directory fails, this function exits nonzero.
@@ -136,27 +135,27 @@ chdir_long (char *dir)
code in the following loop cleaner. */
if (n_leading_slash == 2)
{
- int err;
- /* Find next slash.
- We already know that dir[2] is neither a slash nor '\0'. */
- char *slash = memchr (dir + 3, '/', dir_end - (dir + 3));
- if (slash == NULL)
- {
- errno = ENAMETOOLONG;
- return -1;
- }
- *slash = '\0';
- err = cdb_advance_fd (&cdb, dir);
- *slash = '/';
- if (err != 0)
- goto Fail;
- dir = find_non_slash (slash + 1);
+ int err;
+ /* Find next slash.
+ We already know that dir[2] is neither a slash nor '\0'. */
+ char *slash = memchr (dir + 3, '/', dir_end - (dir + 3));
+ if (slash == NULL)
+ {
+ errno = ENAMETOOLONG;
+ return -1;
+ }
+ *slash = '\0';
+ err = cdb_advance_fd (&cdb, dir);
+ *slash = '/';
+ if (err != 0)
+ goto Fail;
+ dir = find_non_slash (slash + 1);
}
else if (n_leading_slash)
{
- if (cdb_advance_fd (&cdb, "/") != 0)
- goto Fail;
- dir += n_leading_slash;
+ if (cdb_advance_fd (&cdb, "/") != 0)
+ goto Fail;
+ dir += n_leading_slash;
}
assert (*dir != '/');
@@ -164,31 +163,31 @@ chdir_long (char *dir)
while (PATH_MAX <= dir_end - dir)
{
- int err;
- /* Find a slash that is PATH_MAX or fewer bytes away from dir.
- I.e. see if there is a slash that will give us a name of
- length PATH_MAX-1 or less. */
- char *slash = memrchr (dir, '/', PATH_MAX);
- if (slash == NULL)
- {
- errno = ENAMETOOLONG;
- return -1;
- }
-
- *slash = '\0';
- assert (slash - dir < PATH_MAX);
- err = cdb_advance_fd (&cdb, dir);
- *slash = '/';
- if (err != 0)
- goto Fail;
-
- dir = find_non_slash (slash + 1);
+ int err;
+ /* Find a slash that is PATH_MAX or fewer bytes away from dir.
+ I.e. see if there is a slash that will give us a name of
+ length PATH_MAX-1 or less. */
+ char *slash = memrchr (dir, '/', PATH_MAX);
+ if (slash == NULL)
+ {
+ errno = ENAMETOOLONG;
+ return -1;
+ }
+
+ *slash = '\0';
+ assert (slash - dir < PATH_MAX);
+ err = cdb_advance_fd (&cdb, dir);
+ *slash = '/';
+ if (err != 0)
+ goto Fail;
+
+ dir = find_non_slash (slash + 1);
}
if (dir < dir_end)
{
- if (cdb_advance_fd (&cdb, dir) != 0)
- goto Fail;
+ if (cdb_advance_fd (&cdb, dir) != 0)
+ goto Fail;
}
if (cdb_fchdir (&cdb) != 0)
@@ -209,7 +208,6 @@ chdir_long (char *dir)
#if TEST_CHDIR
-# include
# include "closeout.h"
# include "error.h"
@@ -230,10 +228,10 @@ main (int argc, char *argv[])
{
int saved_errno = errno;
if (feof (stdin))
- exit (0);
+ exit (0);
error (EXIT_FAILURE, saved_errno,
- "reading standard input");
+ "reading standard input");
}
else if (len == 0)
exit (0);
@@ -243,12 +241,12 @@ main (int argc, char *argv[])
if (chdir_long (line) != 0)
error (EXIT_FAILURE, errno,
- "chdir_long failed: %s", line);
+ "chdir_long failed: %s", line);
if (argc <= 1)
{
- /* Using `pwd' here makes sense only if it is a robust implementation,
- like the one in coreutils after the 2004-04-19 changes. */
+ /* Using 'pwd' here makes sense only if it is a robust implementation,
+ like the one in coreutils after the 2004-04-19 changes. */
char const *cmd = "pwd";
execlp (cmd, (char *) NULL);
error (EXIT_FAILURE, errno, "%s", cmd);
@@ -263,6 +261,6 @@ main (int argc, char *argv[])
/*
Local Variables:
-compile-command: "gcc -DTEST_CHDIR=1 -DHAVE_CONFIG_H -I.. -g -O -W -Wall chdir-long.c libcoreutils.a"
+compile-command: "gcc -DTEST_CHDIR=1 -g -O -W -Wall chdir-long.c libcoreutils.a"
End:
*/