diff options
Diffstat (limited to 'gnulib-m4/getcwd-path-max.m4')
-rw-r--r-- | gnulib-m4/getcwd-path-max.m4 | 254 |
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 - ]) - ]) -]) |