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[PATCH 1/3] getcwd: consolidate m4 files
|
From: |
Eric Blake |
|
Subject: |
[PATCH 1/3] getcwd: consolidate m4 files |
|
Date: |
Mon, 25 Apr 2011 16:28:25 -0600 |
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 <address@hidden>
---
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 <address@hidden>
+
+ 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 <address@hidden>
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