It was confusing having 1 out of 3 known getcwd problems checked in place, and the other two in separate files.
* m4/getcwd-abort-bug.m4, m4/getcwd-path-max.m4: Delete, moving contents... * m4/getcwd.m4: Here. * modules/getcwd (Files): Reflect the motion. Signed-off-by: Eric Blake <ebl...@redhat.com> --- ChangeLog | 8 ++ m4/getcwd-abort-bug.m4 | 106 ------------------ m4/getcwd-path-max.m4 | 188 ------------------------------- m4/getcwd.m4 | 285 +++++++++++++++++++++++++++++++++++++++++++++++- modules/getcwd | 2 - 5 files changed, 292 insertions(+), 297 deletions(-) delete mode 100644 m4/getcwd-abort-bug.m4 delete mode 100644 m4/getcwd-path-max.m4 diff --git a/ChangeLog b/ChangeLog index 65ed4a0..f113c64 100644 --- a/ChangeLog +++ b/ChangeLog @@ -1,3 +1,11 @@ +2011-04-25 Eric Blake <ebl...@redhat.com> + + getcwd: consolidate m4 files + * m4/getcwd-abort-bug.m4, m4/getcwd-path-max.m4: Delete, moving + contents... + * m4/getcwd.m4: Here. + * modules/getcwd (Files): Reflect the motion. + 2011-04-25 Jim Meyering <meyer...@redhat.com> maint.mk: makefile_at_at_check extend and clean up diff --git a/m4/getcwd-abort-bug.m4 b/m4/getcwd-abort-bug.m4 deleted file mode 100644 index 21be828..0000000 --- a/m4/getcwd-abort-bug.m4 +++ /dev/null @@ -1,106 +0,0 @@ -# serial 2 -# Determine whether getcwd aborts when the length of the working directory -# name is unusually large. Any length between 4k and 16k trigger the bug -# when using glibc-2.4.90-9 or older. - -# Copyright (C) 2006, 2009-2011 Free Software Foundation, Inc. -# This file is free software; the Free Software Foundation -# gives unlimited permission to copy and/or distribute it, -# with or without modifications, as long as this notice is preserved. - -# From Jim Meyering - -# gl_FUNC_GETCWD_ABORT_BUG([ACTION-IF-FOUND[, ACTION-IF-NOT-FOUND]]) -AC_DEFUN([gl_FUNC_GETCWD_ABORT_BUG], -[ - AC_CHECK_DECLS_ONCE([getcwd]) - AC_CHECK_FUNCS([getpagesize]) - AC_CACHE_CHECK([whether getcwd aborts when 4k < cwd_length < 16k], - gl_cv_func_getcwd_abort_bug, - [# Remove any remnants of a previous test. - rm -rf confdir-14B--- - # Arrange for deletion of the temporary directory this test creates. - ac_clean_files="$ac_clean_files confdir-14B---" - AC_RUN_IFELSE( - [AC_LANG_SOURCE( - [[ -#include <stdlib.h> -#include <unistd.h> -#include <limits.h> -#include <string.h> -#include <sys/stat.h> - -/* Don't get link errors because mkdir is redefined to rpl_mkdir. */ -#undef mkdir - -#ifndef S_IRWXU -# define S_IRWXU 0700 -#endif - -/* FIXME: skip the run-test altogether on systems without getpagesize. */ -#if ! HAVE_GETPAGESIZE -# define getpagesize() 0 -#endif - -/* This size is chosen to be larger than PATH_MAX (4k), yet smaller than - the 16kB pagesize on ia64 linux. Those conditions make the code below - trigger a bug in glibc's getcwd implementation before 2.4.90-10. */ -#define TARGET_LEN (5 * 1024) - -int -main () -{ - char const *dir_name = "confdir-14B---"; - char *cwd; - size_t initial_cwd_len; - int fail = 0; - size_t desired_depth; - size_t d; - - /* The bug is triggered when PATH_MAX < getpagesize (), so skip - this relative expensive and invasive test if that's not true. */ - if (getpagesize () <= PATH_MAX) - return 0; - - cwd = getcwd (NULL, 0); - if (cwd == NULL) - return 0; - - initial_cwd_len = strlen (cwd); - free (cwd); - desired_depth = ((TARGET_LEN - 1 - initial_cwd_len) - / (1 + strlen (dir_name))); - for (d = 0; d < desired_depth; d++) - { - if (mkdir (dir_name, S_IRWXU) < 0 || chdir (dir_name) < 0) - { - fail = 3; /* Unable to construct deep hierarchy. */ - break; - } - } - - /* If libc has the bug in question, this invocation of getcwd - results in a failed assertion. */ - cwd = getcwd (NULL, 0); - if (cwd == NULL) - fail = 4; /* getcwd failed. This is ok, and expected. */ - free (cwd); - - /* Call rmdir first, in case the above chdir failed. */ - rmdir (dir_name); - while (0 < d--) - { - if (chdir ("..") < 0) - break; - rmdir (dir_name); - } - - return 0; -} - ]])], - [gl_cv_func_getcwd_abort_bug=no], - [gl_cv_func_getcwd_abort_bug=yes], - [gl_cv_func_getcwd_abort_bug=yes]) - ]) - AS_IF([test $gl_cv_func_getcwd_abort_bug = yes], [$1], [$2]) -]) diff --git a/m4/getcwd-path-max.m4 b/m4/getcwd-path-max.m4 deleted file mode 100644 index 2ab2645..0000000 --- a/m4/getcwd-path-max.m4 +++ /dev/null @@ -1,188 +0,0 @@ -# serial 15 -# Check for several getcwd bugs with long file names. -# If so, arrange to compile the wrapper function. - -# This is necessary for at least GNU libc on linux-2.4.19 and 2.4.20. -# I've heard that this is due to a Linux kernel bug, and that it has -# been fixed between 2.4.21-pre3 and 2.4.21-pre4. */ - -# Copyright (C) 2003-2007, 2009-2011 Free Software Foundation, Inc. -# This file is free software; the Free Software Foundation -# gives unlimited permission to copy and/or distribute it, -# with or without modifications, as long as this notice is preserved. - -# From Jim Meyering - -AC_DEFUN([gl_FUNC_GETCWD_PATH_MAX], -[ - AC_CHECK_DECLS_ONCE([getcwd]) - AC_REQUIRE([gl_USE_SYSTEM_EXTENSIONS]) - AC_CACHE_CHECK([whether getcwd handles long file names properly], - gl_cv_func_getcwd_path_max, - [# Arrange for deletion of the temporary directory this test creates. - ac_clean_files="$ac_clean_files confdir3" - AC_RUN_IFELSE( - [AC_LANG_SOURCE( - [[ -#include <errno.h> -#include <stdlib.h> -#include <unistd.h> -#include <string.h> -#include <limits.h> -#include <sys/stat.h> -#include <sys/types.h> -#include <fcntl.h> - -#ifndef AT_FDCWD -# define AT_FDCWD 0 -#endif -#ifdef ENAMETOOLONG -# define is_ENAMETOOLONG(x) ((x) == ENAMETOOLONG) -#else -# define is_ENAMETOOLONG(x) 0 -#endif - -/* Don't get link errors because mkdir is redefined to rpl_mkdir. */ -#undef mkdir - -#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 = getcwd (buf, PATH_MAX); - size_t initial_cwd_len; - size_t cwd_len; - int fail = 0; - size_t n_chdirs = 0; - - if (cwd == NULL) - exit (10); - - cwd_len = initial_cwd_len = strlen (cwd); - - 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. 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))) - fail = 20; - break; - } - - if (PATH_MAX <= cwd_len && cwd_len < PATH_MAX + DIR_NAME_SIZE) - { - c = getcwd (buf, PATH_MAX); - if (!c && errno == ENOENT) - { - fail = 11; - break; - } - if (c || ! (errno == ERANGE || is_ENAMETOOLONG (errno))) - { - fail = 21; - 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';; - *) gl_cv_func_getcwd_path_max=no;; - esac], - [gl_cv_func_getcwd_path_max=no]) - ]) - case $gl_cv_func_getcwd_path_max in - no,*) - AC_DEFINE([HAVE_PARTLY_WORKING_GETCWD], [1], - [Define to 1 if getcwd works, except it sometimes fails when it shouldn't, - setting errno to ERANGE, ENAMETOOLONG, or ENOENT.]);; - esac -]) diff --git a/m4/getcwd.m4 b/m4/getcwd.m4 index 7098056..5016a1b 100644 --- a/m4/getcwd.m4 +++ b/m4/getcwd.m4 @@ -6,7 +6,7 @@ # with or without modifications, as long as this notice is preserved. # Written by Paul Eggert. -# serial 3 +# serial 4 AC_DEFUN([gl_FUNC_GETCWD_NULL], [ @@ -52,6 +52,289 @@ AC_DEFUN([gl_FUNC_GETCWD_NULL], ]])]) ]) + +# Determine whether getcwd aborts when the length of the working directory +# name is unusually large. Any length between 4k and 16k trigger the bug +# when using glibc-2.4.90-9 or older. +# From Jim Meyering +# gl_FUNC_GETCWD_ABORT_BUG([ACTION-IF-FOUND[, ACTION-IF-NOT-FOUND]]) +AC_DEFUN([gl_FUNC_GETCWD_ABORT_BUG], +[ + AC_CHECK_DECLS_ONCE([getcwd]) + AC_CHECK_FUNCS([getpagesize]) + AC_CACHE_CHECK([whether getcwd aborts when 4k < cwd_length < 16k], + gl_cv_func_getcwd_abort_bug, + [# Remove any remnants of a previous test. + rm -rf confdir-14B--- + # Arrange for deletion of the temporary directory this test creates. + ac_clean_files="$ac_clean_files confdir-14B---" + AC_RUN_IFELSE( + [AC_LANG_SOURCE( + [[ +#include <stdlib.h> +#include <unistd.h> +#include <limits.h> +#include <string.h> +#include <sys/stat.h> + +/* Don't get link errors because mkdir is redefined to rpl_mkdir. */ +#undef mkdir + +#ifndef S_IRWXU +# define S_IRWXU 0700 +#endif + +/* FIXME: skip the run-test altogether on systems without getpagesize. */ +#if ! HAVE_GETPAGESIZE +# define getpagesize() 0 +#endif + +/* This size is chosen to be larger than PATH_MAX (4k), yet smaller than + the 16kB pagesize on ia64 linux. Those conditions make the code below + trigger a bug in glibc's getcwd implementation before 2.4.90-10. */ +#define TARGET_LEN (5 * 1024) + +int +main () +{ + char const *dir_name = "confdir-14B---"; + char *cwd; + size_t initial_cwd_len; + int fail = 0; + size_t desired_depth; + size_t d; + + /* The bug is triggered when PATH_MAX < getpagesize (), so skip + this relative expensive and invasive test if that's not true. */ + if (getpagesize () <= PATH_MAX) + return 0; + + cwd = getcwd (NULL, 0); + if (cwd == NULL) + return 0; + + initial_cwd_len = strlen (cwd); + free (cwd); + desired_depth = ((TARGET_LEN - 1 - initial_cwd_len) + / (1 + strlen (dir_name))); + for (d = 0; d < desired_depth; d++) + { + if (mkdir (dir_name, S_IRWXU) < 0 || chdir (dir_name) < 0) + { + fail = 3; /* Unable to construct deep hierarchy. */ + break; + } + } + + /* If libc has the bug in question, this invocation of getcwd + results in a failed assertion. */ + cwd = getcwd (NULL, 0); + if (cwd == NULL) + fail = 4; /* getcwd failed. This is ok, and expected. */ + free (cwd); + + /* Call rmdir first, in case the above chdir failed. */ + rmdir (dir_name); + while (0 < d--) + { + if (chdir ("..") < 0) + break; + rmdir (dir_name); + } + + return 0; +} + ]])], + [gl_cv_func_getcwd_abort_bug=no], + [gl_cv_func_getcwd_abort_bug=yes], + [gl_cv_func_getcwd_abort_bug=yes]) + ]) + AS_IF([test $gl_cv_func_getcwd_abort_bug = yes], [$1], [$2]) +]) + +# Check for several getcwd bugs with long file names. +# If so, arrange to compile the wrapper function. +# This is necessary for at least GNU libc on linux-2.4.19 and 2.4.20. +# I've heard that this is due to a Linux kernel bug, and that it has +# been fixed between 2.4.21-pre3 and 2.4.21-pre4. +# From Jim Meyering +AC_DEFUN([gl_FUNC_GETCWD_PATH_MAX], +[ + AC_CHECK_DECLS_ONCE([getcwd]) + AC_REQUIRE([gl_USE_SYSTEM_EXTENSIONS]) + AC_CACHE_CHECK([whether getcwd handles long file names properly], + gl_cv_func_getcwd_path_max, + [# Arrange for deletion of the temporary directory this test creates. + ac_clean_files="$ac_clean_files confdir3" + AC_RUN_IFELSE( + [AC_LANG_SOURCE( + [[ +#include <errno.h> +#include <stdlib.h> +#include <unistd.h> +#include <string.h> +#include <limits.h> +#include <sys/stat.h> +#include <sys/types.h> +#include <fcntl.h> + +#ifndef AT_FDCWD +# define AT_FDCWD 0 +#endif +#ifdef ENAMETOOLONG +# define is_ENAMETOOLONG(x) ((x) == ENAMETOOLONG) +#else +# define is_ENAMETOOLONG(x) 0 +#endif + +/* Don't get link errors because mkdir is redefined to rpl_mkdir. */ +#undef mkdir + +#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 = getcwd (buf, PATH_MAX); + size_t initial_cwd_len; + size_t cwd_len; + int fail = 0; + size_t n_chdirs = 0; + + if (cwd == NULL) + exit (10); + + cwd_len = initial_cwd_len = strlen (cwd); + + 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. 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))) + fail = 20; + break; + } + + if (PATH_MAX <= cwd_len && cwd_len < PATH_MAX + DIR_NAME_SIZE) + { + c = getcwd (buf, PATH_MAX); + if (!c && errno == ENOENT) + { + fail = 11; + break; + } + if (c || ! (errno == ERANGE || is_ENAMETOOLONG (errno))) + { + fail = 21; + 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';; + *) gl_cv_func_getcwd_path_max=no;; + esac], + [gl_cv_func_getcwd_path_max=no]) + ]) + case $gl_cv_func_getcwd_path_max in + no,*) + AC_DEFINE([HAVE_PARTLY_WORKING_GETCWD], [1], + [Define to 1 if getcwd works, except it sometimes fails when it shouldn't, + setting errno to ERANGE, ENAMETOOLONG, or ENOENT.]);; + esac +]) + + +dnl Check for all known getcwd bugs; useful for a program likely to be +dnl executed from an arbitrary location, by augmenting native getcwd. AC_DEFUN([gl_FUNC_GETCWD], [ AC_REQUIRE([gl_UNISTD_H_DEFAULTS]) diff --git a/modules/getcwd b/modules/getcwd index 108f14b..de27c9a 100644 --- a/modules/getcwd +++ b/modules/getcwd @@ -3,8 +3,6 @@ Return the current working directory. Files: lib/getcwd.c -m4/getcwd-abort-bug.m4 -m4/getcwd-path-max.m4 m4/getcwd.m4 Depends-on: -- 1.7.4.4