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-rw-r--r--gnulib-m4/getcwd-path-max.m4254
1 files changed, 0 insertions, 254 deletions
diff --git a/gnulib-m4/getcwd-path-max.m4 b/gnulib-m4/getcwd-path-max.m4
deleted file mode 100644
index e9c52d90..00000000
--- a/gnulib-m4/getcwd-path-max.m4
+++ /dev/null
@@ -1,254 +0,0 @@
-# getcwd-path-max.m4
-# serial 26
-dnl Copyright (C) 2003-2007, 2009-2024 Free Software Foundation, Inc.
-dnl This file is free software; the Free Software Foundation
-dnl gives unlimited permission to copy and/or distribute it,
-dnl with or without modifications, as long as this notice is preserved.
-
-# Check for several getcwd bugs with long file names.
-# If so, arrange to compile the wrapper function.
-
-# This is necessary for at least GNU libc on linux-2.4.19 and 2.4.20.
-# I've heard that this is due to a Linux kernel bug, and that it has
-# been fixed between 2.4.21-pre3 and 2.4.21-pre4.
-
-# From Jim Meyering
-
-AC_DEFUN([gl_FUNC_GETCWD_PATH_MAX],
-[
- AC_CHECK_DECLS_ONCE([getcwd, alarm])
- AC_REQUIRE([AC_CANONICAL_HOST]) dnl for cross-compiles
- AC_REQUIRE([gl_USE_SYSTEM_EXTENSIONS])
- AC_CHECK_HEADERS_ONCE([unistd.h])
- AC_REQUIRE([gl_PATHMAX_SNIPPET_PREREQ])
- AC_CACHE_CHECK([whether getcwd handles long file names properly],
- [gl_cv_func_getcwd_path_max],
- [# Arrange for deletion of the temporary directory this test creates.
- ac_clean_files="$ac_clean_files confdir3"
- dnl Please keep this in sync with tests/test-getcwd.c.
- AC_RUN_IFELSE(
- [AC_LANG_SOURCE(
- [[
-#include <errno.h>
-#include <stdlib.h>
-#if HAVE_UNISTD_H
-# include <unistd.h>
-#else
-# include <direct.h>
-#endif
-#if HAVE_DECL_ALARM
-# include <signal.h>
-#endif
-#include <string.h>
-#include <limits.h>
-#include <sys/stat.h>
-#include <sys/types.h>
-#include <fcntl.h>
-
-]gl_PATHMAX_SNIPPET[
-
-#ifndef AT_FDCWD
-# define AT_FDCWD 0
-#endif
-#ifdef ENAMETOOLONG
-# define is_ENAMETOOLONG(x) ((x) == ENAMETOOLONG)
-#else
-# define is_ENAMETOOLONG(x) 0
-#endif
-
-/* Use the getcwd function, not any macro. */
-#undef getcwd
-
-]GL_MDA_DEFINES[
-
-#ifndef S_IRWXU
-# define S_IRWXU 0700
-#endif
-
-/* The length of this name must be 8. */
-#define DIR_NAME "confdir3"
-#define DIR_NAME_LEN 8
-#define DIR_NAME_SIZE (DIR_NAME_LEN + 1)
-
-/* The length of "../". */
-#define DOTDOTSLASH_LEN 3
-
-/* Leftover bytes in the buffer, to work around library or OS bugs. */
-#define BUF_SLOP 20
-
-int
-main ()
-{
-#ifndef PATH_MAX
- /* The Hurd doesn't define this, so getcwd can't exhibit the bug --
- at least not on a local file system. And if we were to start worrying
- about remote file systems, we'd have to enable the wrapper function
- all of the time, just to be safe. That's not worth the cost. */
- exit (0);
-#elif ((INT_MAX / (DIR_NAME_SIZE / DOTDOTSLASH_LEN + 1) \
- - DIR_NAME_SIZE - BUF_SLOP) \
- <= PATH_MAX)
- /* FIXME: Assuming there's a system for which this is true,
- this should be done in a compile test. */
- exit (0);
-#else
- char buf[PATH_MAX * (DIR_NAME_SIZE / DOTDOTSLASH_LEN + 1)
- + DIR_NAME_SIZE + BUF_SLOP];
- char *cwd;
- size_t initial_cwd_len;
- size_t cwd_len;
- int fail;
- size_t n_chdirs;
-
-# if HAVE_DECL_ALARM
- /* This test makes some buggy getcwd implementations take a long time, e.g.
- on NAS devices
- <https://lists.gnu.org/archive/html/bug-gnulib/2024-03/msg00444.html>
- and in sandboxed environments <https://bugs.gentoo.org/447970>.
- Give up after 5 seconds; a getcwd slower than that isn't worth using
- anyway. */
- signal (SIGALRM, SIG_DFL);
- alarm (5);
-# endif
-
- cwd = getcwd (buf, PATH_MAX);
- if (cwd == NULL)
- exit (10);
-
- cwd_len = initial_cwd_len = strlen (cwd);
- fail = 0;
- n_chdirs = 0;
-
- while (1)
- {
- size_t dotdot_max = PATH_MAX * (DIR_NAME_SIZE / DOTDOTSLASH_LEN);
- char *c = NULL;
-
- cwd_len += DIR_NAME_SIZE;
- /* If mkdir or chdir fails, it could be that this system cannot create
- any file with an absolute name longer than PATH_MAX, such as cygwin.
- If so, leave fail as 0, because the current working directory can't
- be too long for getcwd if it can't even be created. On Linux with
- the 9p file system, mkdir fails with error EINVAL when cwd_len gets
- too long; ignore this failure because the getcwd() system call
- produces good results whereas the gnulib substitute calls getdents64
- which fails with error EPROTO.
- For other errors, be pessimistic and consider that as a failure,
- too. */
- if (mkdir (DIR_NAME, S_IRWXU) < 0 || chdir (DIR_NAME) < 0)
- {
- if (! (errno == ERANGE || is_ENAMETOOLONG (errno)))
- #ifdef __linux__
- if (! (errno == EINVAL))
- #endif
- fail = 20;
- break;
- }
-
- if (PATH_MAX <= cwd_len && cwd_len < PATH_MAX + DIR_NAME_SIZE)
- {
- struct stat sb;
-
- c = getcwd (buf, PATH_MAX);
- if (!c && errno == ENOENT)
- {
- fail = 11;
- break;
- }
- if (c)
- {
- fail = 31;
- break;
- }
- if (! (errno == ERANGE || is_ENAMETOOLONG (errno)))
- {
- fail = 21;
- break;
- }
-
- /* Our replacement needs to be able to stat() long ../../paths,
- so generate a path larger than PATH_MAX to check,
- avoiding the replacement if we can't stat(). */
- c = getcwd (buf, cwd_len + 1);
- if (c && !AT_FDCWD && stat (c, &sb) != 0 && is_ENAMETOOLONG (errno))
- {
- fail = 32;
- break;
- }
- }
-
- if (dotdot_max <= cwd_len - initial_cwd_len)
- {
- if (dotdot_max + DIR_NAME_SIZE < cwd_len - initial_cwd_len)
- break;
- c = getcwd (buf, cwd_len + 1);
- if (!c)
- {
- if (! (errno == ERANGE || errno == ENOENT
- || is_ENAMETOOLONG (errno)))
- {
- fail = 22;
- break;
- }
- if (AT_FDCWD || errno == ERANGE || errno == ENOENT)
- {
- fail = 12;
- break;
- }
- }
- }
-
- if (c && strlen (c) != cwd_len)
- {
- fail = 23;
- break;
- }
- ++n_chdirs;
- }
-
- /* Leaving behind such a deep directory is not polite.
- So clean up here, right away, even though the driving
- shell script would also clean up. */
- {
- size_t i;
-
- /* Try rmdir first, in case the chdir failed. */
- rmdir (DIR_NAME);
- for (i = 0; i <= n_chdirs; i++)
- {
- if (chdir ("..") < 0)
- break;
- if (rmdir (DIR_NAME) != 0)
- break;
- }
- }
-
- exit (fail);
-#endif
-}
- ]])],
- [gl_cv_func_getcwd_path_max=yes],
- [case $? in
- 10|11|12) gl_cv_func_getcwd_path_max='no, but it is partly working';;
- 31) gl_cv_func_getcwd_path_max='no, it has the AIX bug';;
- 32) gl_cv_func_getcwd_path_max='yes, but with shorter paths';;
- *) gl_cv_func_getcwd_path_max=no;;
- esac],
- [# Cross-compilation guesses:
- case "$host_os" in
- aix*) # On AIX, it has the AIX bug.
- gl_cv_func_getcwd_path_max='guessing no, it has the AIX bug' ;;
- gnu*) # On Hurd, it is 'yes'.
- gl_cv_func_getcwd_path_max='guessing yes' ;;
- linux* | kfreebsd*)
- # On older Linux+glibc it's 'no, but it is partly working',
- # on newer Linux+glibc it's 'yes'.
- # On Linux+musl libc, it's 'no, but it is partly working'.
- # On kFreeBSD+glibc, it's 'no, but it is partly working'.
- gl_cv_func_getcwd_path_max='guessing no, but it is partly working' ;;
- *) # If we don't know, obey --enable-cross-guesses.
- gl_cv_func_getcwd_path_max="$gl_cross_guess_normal" ;;
- esac
- ])
- ])
-])