On 12/11/20 3:47 AM, Bruno Haible wrote:
This patch introduced a unit test regression on AIX 7.2....
../../gltests/test-canonicalize.c:112: assertion 'result1 == NULL' failed
FAIL test-canonicalize (exit status: 134)
Thanks for reporting it. My recent changes to the canonicalize code assumed
POSIX, but AIX readlink departs from the POSIX spec by failing with ERANGE
instead of truncating link contents. Plus, the code had a natural assumption
that POSIX might not support, namely, that readlink ("a/", ...) should fail
with ENOTDIR (not EINVAL) when "a" is not a directory.
I installed the attached patches to work around these issues, along with
other stuff I noticed while testing this under AIX 7.2 (gcc119, which is
power8-aix). The relevant unit tests succeed for me now.
From 4cb6b1493983e76eafa2da3aabff87510f2d63d5 Mon Sep 17 00:00:00 2001
From: Paul Eggert <egg...@cs.ucla.edu>
Date: Sun, 13 Dec 2020 16:48:26 -0800
Subject: [PATCH 1/5] readlink, readlinkat: add ERANGE portability
Fix some portability issues with Gnulib's readlink and readlinkat,
notably mostly working around the ERANGE problem in AIX and HP-UX.
* doc/posix-functions/readlink.texi:
* doc/posix-functions/readlinkat.texi:
ERANGE problem is mostly fixed now. Mention AIX problem with
trailing / and EINVAL. Lessen differences between these two files.
* lib/readlink.c (rpl_readlink):
* lib/readlinkat.c (rpl_readlinkat):
If stat ("FILE/", ...) reports EOVERFLOW, treat FILE/ as an
existing directory. Mostly work around READLINK_TRUNCATE BUG.
Lessen spurious differences between the readlink and readlinkat code.
* lib/readlinkat.c (rpl_readlinkat):
Fix bug where stat was used where fstatat was intended.
* m4/readlink.m4 (gl_FUNC_READLINK):
Rename gl_cv_func_readlink_works to gl_cv_func_readlink_trailing_slash
to identify readlink problems more precisely. All uses changed.
Guess no on AIX or HP-UX for this variable.
Add check for whether readlink truncates results,
and define new macro READLINK_TRUCATE_BUG accordingly.
* m4/readlinkat.m4 (gl_FUNC_READLINKAT):
Also check gl_cv_func_readlink_trailing_slash when deciding
whether to replace readlinkat.
* modules/readlinkat (Depends-on): Most dependencies are also
needed if replacing readlinkat. fstatat is different, as it
is needed only if replacing an existing readlinkat.
---
ChangeLog | 29 ++++++++++++++
doc/posix-functions/readlink.texi | 41 ++++++++++++++-----
doc/posix-functions/readlinkat.texi | 35 ++++++++++++-----
lib/readlink.c | 48 ++++++++++++++++++-----
lib/readlinkat.c | 47 ++++++++++++++++++----
m4/readlink.m4 | 61 ++++++++++++++++++++++++-----
m4/readlinkat.m4 | 13 +++---
modules/readlinkat | 20 +++++-----
8 files changed, 230 insertions(+), 64 deletions(-)
diff --git a/ChangeLog b/ChangeLog
index b3f62960f..2ebf31995 100644
--- a/ChangeLog
+++ b/ChangeLog
@@ -1,3 +1,32 @@
+2020-12-13 Paul Eggert <egg...@cs.ucla.edu>
+
+ readlink, readlinkat: add ERANGE portability
+ Fix some portability issues with Gnulib's readlink and readlinkat,
+ notably mostly working around the ERANGE problem in AIX and HP-UX.
+ * doc/posix-functions/readlink.texi:
+ * doc/posix-functions/readlinkat.texi:
+ ERANGE problem is mostly fixed now. Mention AIX problem with
+ trailing / and EINVAL. Lessen differences between these two files.
+ * lib/readlink.c (rpl_readlink):
+ * lib/readlinkat.c (rpl_readlinkat):
+ If stat ("FILE/", ...) reports EOVERFLOW, treat FILE/ as an
+ existing directory. Mostly work around READLINK_TRUNCATE BUG.
+ Lessen spurious differences between the readlink and readlinkat code.
+ * lib/readlinkat.c (rpl_readlinkat):
+ Fix bug where stat was used where fstatat was intended.
+ * m4/readlink.m4 (gl_FUNC_READLINK):
+ Rename gl_cv_func_readlink_works to gl_cv_func_readlink_trailing_slash
+ to identify readlink problems more precisely. All uses changed.
+ Guess no on AIX or HP-UX for this variable.
+ Add check for whether readlink truncates results,
+ and define new macro READLINK_TRUCATE_BUG accordingly.
+ * m4/readlinkat.m4 (gl_FUNC_READLINKAT):
+ Also check gl_cv_func_readlink_trailing_slash when deciding
+ whether to replace readlinkat.
+ * modules/readlinkat (Depends-on): Most dependencies are also
+ needed if replacing readlinkat. fstatat is different, as it
+ is needed only if replacing an existing readlinkat.
+
2020-12-13 Bruno Haible <br...@clisp.org>
spawn-pipe: Fix hanging processes on Windows (regression 2020-11-30).
diff --git a/doc/posix-functions/readlink.texi b/doc/posix-functions/readlink.texi
index b2ccceee7..d4421380a 100644
--- a/doc/posix-functions/readlink.texi
+++ b/doc/posix-functions/readlink.texi
@@ -9,34 +9,55 @@ Gnulib module: readlink
Portability problems fixed by Gnulib:
@itemize
@item
-Some platforms mistakenly succeed on @code{readlink("link/",buf,len)}:
+This function is missing on some platforms:
+mingw, MSVC 14.
+@item
+Some platforms mistakenly succeed on file names ending in @file{/}:
FreeBSD 7.2, Solaris 9, Mac OS X 10.10.
@item
-On some platforms, @code{readlink} returns @code{int} instead of
+On some platforms, this function returns @code{int} instead of
@code{ssize_t}:
glibc 2.4, FreeBSD 6.0, OpenBSD 6.7, Cygwin 1.5.x, AIX 7.1.
+@end itemize
+
+Portability problems mostly fixed by Gnulib:
+@itemize
@item
-This function is missing on some platforms:
-mingw, MSVC 14.
+On some platforms, this function fails and sets @code{errno} to
+@code{ERANGE} rather than returning truncated contents:
+AIX 7.2, HP-UX 11.
+The Gnulib replacement normally works as POSIX requires by returning
+the truncated contents. However, if the full link contents are
+unreasonably large (more than 4000 bytes) the replacement clears the
+entire buffer and returns the buffer size; although this is not a
+complete fix, it suffices for typical callers, which ignore the buffer
+contents anyway.
@end itemize
Portability problems not fixed by Gnulib:
@itemize
@item
-When @code{readlink} is called on a directory: In the case of NFS mounted
+This function always fails on platforms that don't support symlinks:
+mingw, MSVC 14.
+@item
+When this function is called on a directory: In the case of NFS mounted
directories, Cygwin sets @code{errno} to @code{ENOENT} or @code{EIO} instead of
@code{EINVAL}. To avoid this problem, check for a directory before calling
-@code{readlink}.
+this function.
@item
-When @code{readlink} is called on a file that is not a symbolic link:
+When this function is called on a file that is not a symbolic link:
IRIX may set @code{errno} to @code{ENXIO} instead of @code{EINVAL}. Cygwin
may set errno to @code{EACCES} instead of @code{EINVAL}.
@item
+When this function fails because it is called on an existing
+non-directory's name concatenated to @file{/},
+it sets @code{errno} to @code{EINVAL}:
+AIX 7.2.
+@item
Symlink contents do not always have a trailing null byte, and there is
no indication if symlink contents were truncated if the return value
-matches the length. Furthermore, AIX 5.1 and HP-UX 11 set
-@code{errno} to @code{ERANGE} rather than returning truncated
-contents, and Linux sets @code{errno} to @code{EINVAL} if the
+matches the length. Furthermore,
+Linux sets @code{errno} to @code{EINVAL} if the
requested length is zero. Use the gnulib module @code{areadlink} for
improved ability to read symlink contents.
@end itemize
diff --git a/doc/posix-functions/readlinkat.texi b/doc/posix-functions/readlinkat.texi
index 246894605..2cd2e7be5 100644
--- a/doc/posix-functions/readlinkat.texi
+++ b/doc/posix-functions/readlinkat.texi
@@ -13,13 +13,26 @@ This function is missing on some platforms:
glibc 2.3.6, Mac OS X 10.9, FreeBSD 6.0, NetBSD 5.0, OpenBSD 3.8, Minix 3.1.8, AIX 5.1, HP-UX 11, IRIX 6.5, Solaris 10, Cygwin 1.5.x, mingw, MSVC 14, Android 4.4.
But the replacement function is not safe to be used in libraries and is not multithread-safe.
@item
-Some platforms mistakenly succeed on @code{readlink("link/",buf,len)}:
-Mac OS X 10.10.
+Some platforms mistakenly succeed on file names ending in @file{/}:
+OS X 10.10.
@item
-On some platforms, @code{readlinkat} returns @code{int} instead of
+On some platforms, this function returns @code{int} instead of
@code{ssize_t}:
AIX 7.1.
+@end itemize
+
+Portability problems mostly fixed by Gnulib:
+@itemize
@item
+On some platforms, this function fails and sets @code{errno} to
+@code{ERANGE} rather than returning truncated contents:
+AIX 7.2.
+The Gnulib replacement normally works as POSIX requires by returning
+the truncated contents. However, if the full link contents are
+unreasonably large (more than 4000 bytes) the replacement clears the
+entire buffer and returns the buffer size; although this is not a
+complete fix, it suffices for typical callers, which ignore the buffer
+contents anyway.
@end itemize
Portability problems not fixed by Gnulib:
@@ -28,20 +41,24 @@ Portability problems not fixed by Gnulib:
This function always fails on platforms that don't support symlinks:
mingw, MSVC 14.
@item
-When @code{readlink} is called on a directory: In the case of NFS mounted
+When this function is called on a directory: In the case of NFS mounted
directories, Cygwin sets @code{errno} to @code{ENOENT} or @code{EIO} instead of
@code{EINVAL}. To avoid this problem, check for a directory before calling
-@code{readlink}.
+this function.
@item
-When @code{readlink} is called on a file that is not a symbolic link:
+When this function is called on a file that is not a symbolic link:
IRIX may set @code{errno} to @code{ENXIO} instead of @code{EINVAL}. Cygwin
may set errno to @code{EACCES} instead of @code{EINVAL}.
@item
+When this function fails because it is called on an existing
+non-directory's name concatenated to @file{/},
+it sets @code{errno} to @code{EINVAL}:
+AIX 7.2.
+@item
Symlink contents do not always have a trailing null byte, and there is
no indication if symlink contents were truncated if the return value
-matches the length. Furthermore, AIX 5.1 and HP-UX 11 set
-@code{errno} to @code{ERANGE} rather than returning truncated
-contents, and Linux sets @code{errno} to @code{EINVAL} if the
+matches the length. Furthermore,
+Linux sets @code{errno} to @code{EINVAL} if the
requested length is zero. Use the gnulib module @code{areadlink} for
improved ability to read symlink contents.
@end itemize
diff --git a/lib/readlink.c b/lib/readlink.c
index 4d392ef69..531913eba 100644
--- a/lib/readlink.c
+++ b/lib/readlink.c
@@ -1,4 +1,4 @@
-/* Stub for readlink().
+/* Read the contents of a symbolic link.
Copyright (C) 2003-2007, 2009-2020 Free Software Foundation, Inc.
This program is free software: you can redistribute it and/or modify
@@ -29,7 +29,7 @@
such as DJGPP 2.03 and mingw32. */
ssize_t
-readlink (const char *name, char *buf _GL_UNUSED,
+readlink (char const *file, char *buf _GL_UNUSED,
size_t bufsize _GL_UNUSED)
{
struct stat statbuf;
@@ -37,7 +37,7 @@ readlink (const char *name, char *buf _GL_UNUSED,
/* In general we should use lstat() here, not stat(). But on platforms
without symbolic links, lstat() - if it exists - would be equivalent to
stat(), therefore we can use stat(). This saves us a configure check. */
- if (stat (name, &statbuf) >= 0)
+ if (stat (file, &statbuf) >= 0)
errno = EINVAL;
return -1;
}
@@ -51,24 +51,54 @@ readlink (const char *name, char *buf _GL_UNUSED,
for Solaris 9. */
ssize_t
-rpl_readlink (const char *name, char *buf, size_t bufsize)
+rpl_readlink (char const *file, char *buf, size_t bufsize)
{
# if READLINK_TRAILING_SLASH_BUG
- size_t len = strlen (name);
- if (len && name[len - 1] == '/')
+ size_t file_len = strlen (file);
+ if (file_len && file[file_len - 1] == '/')
{
- /* Even if name without the slash is a symlink to a directory,
+ /* Even if FILE without the slash is a symlink to a directory,
both lstat() and stat() must resolve the trailing slash to
the directory rather than the symlink. We can therefore
safely use stat() to distinguish between EINVAL and
ENOTDIR/ENOENT, avoiding extra overhead of rpl_lstat(). */
struct stat st;
- if (stat (name, &st) == 0)
+ if (stat (file, &st) == 0 || errno == EOVERFLOW)
errno = EINVAL;
return -1;
}
# endif /* READLINK_TRAILING_SLASH_BUG */
- return readlink (name, buf, bufsize);
+
+ ssize_t r = readlink (file, buf, bufsize);
+
+# if READLINK_TRUNCATE_BUG
+ if (r < 0 && errno == ERANGE)
+ {
+ /* Try again with a bigger buffer. This is just for test cases;
+ real code invariably discards short reads. */
+ char stackbuf[4032];
+ r = readlink (file, stackbuf, sizeof stackbuf);
+ if (r < 0)
+ {
+ if (errno == ERANGE)
+ {
+ /* Clear the buffer, which is good enough for real code.
+ Thankfully, no test cases try short reads of enormous
+ symlinks and what would be the point anyway? */
+ r = bufsize;
+ memset (buf, 0, r);
+ }
+ }
+ else
+ {
+ if (bufsize < r)
+ r = bufsize;
+ memcpy (buf, stackbuf, r);
+ }
+ }
+# endif
+
+ return r;
}
#endif /* HAVE_READLINK */
diff --git a/lib/readlinkat.c b/lib/readlinkat.c
index 68ec65ebf..7a41208eb 100644
--- a/lib/readlinkat.c
+++ b/lib/readlinkat.c
@@ -28,10 +28,11 @@
#if HAVE_READLINKAT
+# undef fstatat
# undef readlinkat
ssize_t
-rpl_readlinkat (int fd, char const *file, char *buf, size_t len)
+rpl_readlinkat (int fd, char const *file, char *buf, size_t bufsize)
{
# if READLINK_TRAILING_SLASH_BUG
size_t file_len = strlen (file);
@@ -40,15 +41,45 @@ rpl_readlinkat (int fd, char const *file, char *buf, size_t len)
/* Even if FILE without the slash is a symlink to a directory,
both lstat() and stat() must resolve the trailing slash to
the directory rather than the symlink. We can therefore
- safely use stat() to distinguish between EINVAL and
- ENOTDIR/ENOENT, avoiding extra overhead of rpl_lstat(). */
+ safely use fstatat(..., 0) to distinguish between EINVAL and
+ ENOTDIR/ENOENT, avoiding extra overhead of rpl_fstatat(). */
struct stat st;
- if (stat (file, &st) == 0)
+ if (fstatat (fd, file, &st, 0) == 0 || errno == EOVERFLOW)
errno = EINVAL;
return -1;
}
# endif /* READLINK_TRAILING_SLASH_BUG */
- return readlinkat (fd, file, buf, len);
+
+ ssize_t r = readlinkat (fd, file, buf, bufsize);
+
+# if READLINK_TRUNCATE_BUG
+ if (r < 0 && errno == ERANGE)
+ {
+ /* Try again with a bigger buffer. This is just for test cases;
+ real code invariably discards short reads. */
+ char stackbuf[4032];
+ r = readlinkat (fd, file, stackbuf, sizeof stackbuf);
+ if (r < 0)
+ {
+ if (errno == ERANGE)
+ {
+ /* Clear the buffer, which is good enough for real code.
+ Thankfully, no test cases try short reads of enormous
+ symlinks and what would be the point anyway? */
+ r = bufsize;
+ memset (buf, 0, r);
+ }
+ }
+ else
+ {
+ if (bufsize < r)
+ r = bufsize;
+ memcpy (buf, stackbuf, r);
+ }
+ }
+# endif
+
+ return r;
}
#else
@@ -61,7 +92,7 @@ rpl_readlinkat (int fd, char const *file, char *buf, size_t len)
readlinkat worthless since readlink does not guarantee a
NUL-terminated buffer. Assume this was a bug in POSIX. */
-/* Read the contents of symlink FILE into buffer BUF of size LEN, in the
+/* Read the contents of symlink FILE into buffer BUF of size BUFSIZE, in the
directory open on descriptor FD. If possible, do it without changing
the working directory. Otherwise, resort to using save_cwd/fchdir,
then readlink/restore_cwd. If either the save_cwd or the restore_cwd
@@ -69,8 +100,8 @@ rpl_readlinkat (int fd, char const *file, char *buf, size_t len)
# define AT_FUNC_NAME readlinkat
# define AT_FUNC_F1 readlink
-# define AT_FUNC_POST_FILE_PARAM_DECLS , char *buf, size_t len
-# define AT_FUNC_POST_FILE_ARGS , buf, len
+# define AT_FUNC_POST_FILE_PARAM_DECLS , char *buf, size_t bufsize
+# define AT_FUNC_POST_FILE_ARGS , buf, bufsize
# define AT_FUNC_RESULT ssize_t
# include "at-func.c"
# undef AT_FUNC_NAME
diff --git a/m4/readlink.m4 b/m4/readlink.m4
index 9aa9e46da..c7f436a31 100644
--- a/m4/readlink.m4
+++ b/m4/readlink.m4
@@ -1,4 +1,4 @@
-# readlink.m4 serial 15
+# readlink.m4 serial 16
dnl Copyright (C) 2003, 2007, 2009-2020 Free Software Foundation, Inc.
dnl This file is free software; the Free Software Foundation
dnl gives unlimited permission to copy and/or distribute it,
@@ -23,7 +23,7 @@ AC_DEFUN([gl_FUNC_READLINK],
dnl Solaris 9 ignores trailing slash.
dnl FreeBSD 7.2 dereferences only one level of links with trailing slash.
AC_CACHE_CHECK([whether readlink handles trailing slash correctly],
- [gl_cv_func_readlink_works],
+ [gl_cv_func_readlink_trailing_slash],
[# We have readlink, so assume ln -s works.
ln -s conftest.no-such conftest.link
ln -s conftest.link conftest.lnk2
@@ -32,18 +32,22 @@ AC_DEFUN([gl_FUNC_READLINK],
[[#include <unistd.h>
]], [[char buf[20];
return readlink ("conftest.lnk2/", buf, sizeof buf) != -1;]])],
- [gl_cv_func_readlink_works=yes], [gl_cv_func_readlink_works=no],
+ [gl_cv_func_readlink_trailing_slash=yes],
+ [gl_cv_func_readlink_trailing_slash=no],
[case "$host_os" in
- # Guess yes on Linux systems.
- linux-* | linux) gl_cv_func_readlink_works="guessing yes" ;;
- # Guess yes on glibc systems.
- *-gnu* | gnu*) gl_cv_func_readlink_works="guessing yes" ;;
- # If we don't know, obey --enable-cross-guesses.
- *) gl_cv_func_readlink_works="$gl_cross_guess_normal" ;;
+ # Guess yes on Linux or glibc systems.
+ linux-* | linux | *-gnu* | gnu*)
+ gl_cv_func_readlink_trailing_slash="guessing yes" ;;
+ # Guess no on AIX or HP-UX.
+ aix* | hpux*)
+ gl_cv_func_readlink_trailing_slash="guessing no" ;;
+ # If we don't know, obey --enable-cross-guesses.
+ *)
+ gl_cv_func_readlink_trailing_slash="$gl_cross_guess_normal" ;;
esac
])
rm -f conftest.link conftest.lnk2])
- case "$gl_cv_func_readlink_works" in
+ case "$gl_cv_func_readlink_trailing_slash" in
*yes)
if test "$gl_cv_decl_readlink_works" != yes; then
REPLACE_READLINK=1
@@ -55,6 +59,43 @@ AC_DEFUN([gl_FUNC_READLINK],
REPLACE_READLINK=1
;;
esac
+
+ AC_CACHE_CHECK([whether readlink truncates results correctly],
+ [gl_cv_func_readlink_truncate],
+ [# We have readlink, so assume ln -s works.
+ ln -s ab conftest.link
+ AC_RUN_IFELSE(
+ [AC_LANG_PROGRAM(
+ [[#include <unistd.h>
+]], [[char c;
+ return readlink ("conftest.link", &c, 1) != 1;]])],
+ [gl_cv_func_readlink_truncate=yes],
+ [gl_cv_func_readlink_truncate=no],
+ [case "$host_os" in
+ # Guess yes on Linux or glibc systems.
+ linux-* | linux | *-gnu* | gnu*)
+ gl_cv_func_readlink_truncate="guessing yes" ;;
+ # Guess no on AIX or HP-UX.
+ aix* | hpux*)
+ gl_cv_func_readlink_truncate="guessing no" ;;
+ # If we don't know, obey --enable-cross-guesses.
+ *)
+ gl_cv_func_readlink_truncate="$gl_cross_guess_normal" ;;
+ esac
+ ])
+ rm -f conftest.link conftest.lnk2])
+ case $gl_cv_func_readlink_truncate in
+ *yes)
+ if test "$gl_cv_decl_readlink_works" != yes; then
+ REPLACE_READLINK=1
+ fi
+ ;;
+ *)
+ AC_DEFINE([READLINK_TRUNCATE_BUG], [1], [Define to 1 if readlink
+ sets errno instead of truncating a too-long link.])
+ REPLACE_READLINK=1
+ ;;
+ esac
fi
])
diff --git a/m4/readlinkat.m4 b/m4/readlinkat.m4
index 6ef1f590c..73e343f74 100644
--- a/m4/readlinkat.m4
+++ b/m4/readlinkat.m4
@@ -1,4 +1,4 @@
-# serial 5
+# serial 6
# See if we need to provide readlinkat replacement.
dnl Copyright (C) 2009-2020 Free Software Foundation, Inc.
@@ -26,13 +26,10 @@ AC_DEFUN([gl_FUNC_READLINKAT],
ssize_t readlinkat (int, char const *, char *, size_t);]])],
[gl_cv_decl_readlinkat_works=yes],
[gl_cv_decl_readlinkat_works=no])])
- # Assume readinkat has the same trailing slash bug as readlink,
- # as is the case on Mac Os X 10.10
- case "$gl_cv_func_readlink_works" in
- *yes)
- if test "$gl_cv_decl_readlinkat_works" != yes; then
- REPLACE_READLINKAT=1
- fi
+ # Assume readlinkat has the same bugs as readlink,
+ # as is the case on OS X 10.10 with trailing slashes.
+ case $gl_cv_decl_readlinkat_works,$gl_cv_func_readlink_trailing_slash,$gl_cv_func_readlink_truncate in
+ *yes,*yes,*yes)
;;
*)
REPLACE_READLINKAT=1
diff --git a/modules/readlinkat b/modules/readlinkat
index 3bc723965..171ee31e0 100644
--- a/modules/readlinkat
+++ b/modules/readlinkat
@@ -9,16 +9,16 @@ m4/readlinkat.m4
Depends-on:
unistd
extensions
-at-internal [test $HAVE_READLINKAT = 0]
-errno [test $HAVE_READLINKAT = 0]
-fchdir [test $HAVE_READLINKAT = 0]
-fcntl-h [test $HAVE_READLINKAT = 0]
-filename [test $HAVE_READLINKAT = 0]
-openat-die [test $HAVE_READLINKAT = 0]
-openat-h [test $HAVE_READLINKAT = 0]
-save-cwd [test $HAVE_READLINKAT = 0]
-stat [test $HAVE_READLINKAT = 0]
-readlink [test $HAVE_READLINKAT = 0]
+at-internal [test $HAVE_READLINKAT = 0 || test $REPLACE_READLINKAT = 1]
+errno [test $HAVE_READLINKAT = 0 || test $REPLACE_READLINKAT = 1]
+fchdir [test $HAVE_READLINKAT = 0 || test $REPLACE_READLINKAT = 1]
+fcntl-h [test $HAVE_READLINKAT = 0 || test $REPLACE_READLINKAT = 1]
+filename [test $HAVE_READLINKAT = 0 || test $REPLACE_READLINKAT = 1]
+fstatat [test $HAVE_READLINKAT = 1 && test $REPLACE_READLINKAT = 1]
+openat-die [test $HAVE_READLINKAT = 0 || test $REPLACE_READLINKAT = 1]
+openat-h [test $HAVE_READLINKAT = 0 || test $REPLACE_READLINKAT = 1]
+save-cwd [test $HAVE_READLINKAT = 0 || test $REPLACE_READLINKAT = 1]
+readlink [test $HAVE_READLINKAT = 0 || test $REPLACE_READLINKAT = 1]
configure.ac:
gl_FUNC_READLINKAT
--
2.27.0
From e9df119be4478335d5d499fa8aefa91e37729efc Mon Sep 17 00:00:00 2001
From: Paul Eggert <egg...@cs.ucla.edu>
Date: Sun, 13 Dec 2020 16:51:58 -0800
Subject: [PATCH 2/5] getcwd: port to AIX
* lib/getcwd.c [!_LIBC]: Undef stat64 before #defining it,
in case our sys/stat.h #defined a function macro with the same name.
---
ChangeLog | 4 ++++
lib/getcwd.c | 1 +
2 files changed, 5 insertions(+)
diff --git a/ChangeLog b/ChangeLog
index 2ebf31995..7162110c9 100644
--- a/ChangeLog
+++ b/ChangeLog
@@ -1,5 +1,9 @@
2020-12-13 Paul Eggert <egg...@cs.ucla.edu>
+ getcwd: port to AIX
+ * lib/getcwd.c [!_LIBC]: Undef stat64 before #defining it,
+ in case our sys/stat.h #defined a function macro with the same name.
+
readlink, readlinkat: add ERANGE portability
Fix some portability issues with Gnulib's readlink and readlinkat,
notably mostly working around the ERANGE problem in AIX and HP-UX.
diff --git a/lib/getcwd.c b/lib/getcwd.c
index 9b74b7b0c..418c1e5b9 100644
--- a/lib/getcwd.c
+++ b/lib/getcwd.c
@@ -92,6 +92,7 @@
# define GETCWD_RETURN_TYPE char *
# define __close_nocancel_nostatus close
# define __getcwd_generic rpl_getcwd
+# undef stat64
# define stat64 stat
# define __fstat64 fstat
# define __fstatat64 fstatat
--
2.27.0
From dedb07baaa165a7b25110ddc47658f02935eceb3 Mon Sep 17 00:00:00 2001
From: Paul Eggert <egg...@cs.ucla.edu>
Date: Sun, 13 Dec 2020 16:56:10 -0800
Subject: [PATCH 3/5] Assume readlink/readlinkat ERANGE fix
* lib/areadlink-with-size.c (areadlink_with_size):
* lib/areadlinkat-with-size.c (areadlinkat_with_size):
* lib/careadlinkat.c (readlink_stk):
Do not worry about readlink or readlinkat failing with errno == ERANGE,
since the Gnulib readlink and readlinkat modules now fix that.
---
ChangeLog | 7 +++++++
lib/areadlink-with-size.c | 4 +---
lib/areadlinkat-with-size.c | 4 +---
lib/careadlinkat.c | 15 +++++----------
4 files changed, 14 insertions(+), 16 deletions(-)
diff --git a/ChangeLog b/ChangeLog
index 7162110c9..1c5fd762d 100644
--- a/ChangeLog
+++ b/ChangeLog
@@ -1,5 +1,12 @@
2020-12-13 Paul Eggert <egg...@cs.ucla.edu>
+ Assume readlink/readlinkat ERANGE fix
+ * lib/areadlink-with-size.c (areadlink_with_size):
+ * lib/areadlinkat-with-size.c (areadlinkat_with_size):
+ * lib/careadlinkat.c (readlink_stk):
+ Do not worry about readlink or readlinkat failing with errno == ERANGE,
+ since the Gnulib readlink and readlinkat modules now fix that.
+
getcwd: port to AIX
* lib/getcwd.c [!_LIBC]: Undef stat64 before #defining it,
in case our sys/stat.h #defined a function macro with the same name.
diff --git a/lib/areadlink-with-size.c b/lib/areadlink-with-size.c
index 86ddd6089..4978b79bb 100644
--- a/lib/areadlink-with-size.c
+++ b/lib/areadlink-with-size.c
@@ -88,9 +88,7 @@ areadlink_with_size (char const *file, size_t size)
r = readlink (file, buf, buf_size);
link_length = r;
- /* On AIX 5L v5.3 and HP-UX 11i v2 04/09, readlink returns -1
- with errno == ERANGE if the buffer is too small. */
- if (r < 0 && errno != ERANGE)
+ if (r < 0)
{
int saved_errno = errno;
free (buffer);
diff --git a/lib/areadlinkat-with-size.c b/lib/areadlinkat-with-size.c
index b41a5e0c4..b3092f2a3 100644
--- a/lib/areadlinkat-with-size.c
+++ b/lib/areadlinkat-with-size.c
@@ -92,9 +92,7 @@ areadlinkat_with_size (int fd, char const *file, size_t size)
r = readlinkat (fd, file, buf, buf_size);
link_length = r;
- /* On AIX 5L v5.3 and HP-UX 11i v2 04/09, readlink returns -1
- with errno == ERANGE if the buffer is too small. */
- if (r < 0 && errno != ERANGE)
+ if (r < 0)
{
int saved_errno = errno;
free (buffer);
diff --git a/lib/careadlinkat.c b/lib/careadlinkat.c
index 79cc3b3a0..26fe84df5 100644
--- a/lib/careadlinkat.c
+++ b/lib/careadlinkat.c
@@ -90,18 +90,13 @@ readlink_stk (int fd, char const *filename,
size_t link_size;
if (link_length < 0)
{
- /* On AIX 5L v5.3 and HP-UX 11i v2 04/09, readlink returns -1
- with errno == ERANGE if the buffer is too small. */
- int readlinkat_errno = errno;
- if (readlinkat_errno != ERANGE)
+ if (buf != buffer)
{
- if (buf != buffer)
- {
- alloc->free (buf);
- errno = readlinkat_errno;
- }
- return NULL;
+ int readlinkat_errno = errno;
+ alloc->free (buf);
+ errno = readlinkat_errno;
}
+ return NULL;
}
link_size = link_length;
--
2.27.0
From 23ba9a736af11ca355b337d0a3d51daef82be0ef Mon Sep 17 00:00:00 2001
From: Paul Eggert <egg...@cs.ucla.edu>
Date: Sun, 13 Dec 2020 17:16:01 -0800
Subject: [PATCH 4/5] canonicalize: fix AIX test failures
Problem reported by Bruno Haible in:
https://lists.gnu.org/r/bug-gnulib/2020-12/msg00109.html
* lib/canonicalize.c (canonicalize_filename_mode):
When testing a file name ending in '/', use stat rather than
readlink, so that it does the right thing on AIX.
* modules/canonicalize (Depends-on): Add readlink, to pull in the
recent changes in the Gnulib readlink module.
---
ChangeLog | 9 +++++++++
lib/canonicalize.c | 37 ++++++++++++++++++++++---------------
modules/canonicalize | 1 +
3 files changed, 32 insertions(+), 15 deletions(-)
diff --git a/ChangeLog b/ChangeLog
index 1c5fd762d..b8213ada0 100644
--- a/ChangeLog
+++ b/ChangeLog
@@ -1,5 +1,14 @@
2020-12-13 Paul Eggert <egg...@cs.ucla.edu>
+ canonicalize: fix AIX test failures
+ Problem reported by Bruno Haible in:
+ https://lists.gnu.org/r/bug-gnulib/2020-12/msg00109.html
+ * lib/canonicalize.c (canonicalize_filename_mode):
+ When testing a file name ending in '/', use stat rather than
+ readlink, so that it does the right thing on AIX.
+ * modules/canonicalize (Depends-on): Add readlink, to pull in the
+ recent changes in the Gnulib readlink module.
+
Assume readlink/readlinkat ERANGE fix
* lib/areadlink-with-size.c (areadlink_with_size):
* lib/areadlinkat-with-size.c (areadlinkat_with_size):
diff --git a/lib/canonicalize.c b/lib/canonicalize.c
index e44793d14..e50347b10 100644
--- a/lib/canonicalize.c
+++ b/lib/canonicalize.c
@@ -211,9 +211,13 @@ canonicalize_filename_mode (const char *name, canonicalize_mode_t can_mode)
for (end = start; *end && !ISSLASH (*end); ++end)
/* Nothing. */;
- if (end - start == 1 && start[0] == '.')
+ /* Length of this file name component; it can be zero if a file
+ name ends in '/'. */
+ idx_t startlen = end - start;
+
+ if (startlen == 1 && start[0] == '.')
/* nothing */;
- else if (end - start == 2 && start[0] == '.' && start[1] == '.')
+ else if (startlen == 2 && start[0] == '.' && start[1] == '.')
{
/* Back up to previous component, ignore if at root already. */
if (dest > rname + prefix_len + 1)
@@ -228,27 +232,28 @@ canonicalize_filename_mode (const char *name, canonicalize_mode_t can_mode)
if (!ISSLASH (dest[-1]))
*dest++ = '/';
- if (rname_limit - dest <= end - start)
+ if (rname_limit - dest <= startlen)
{
idx_t dest_offset = dest - rname;
idx_t new_size = rname_limit - rname;
- if (end - start + 1 > PATH_MAX)
- new_size += end - start + 1;
- else
- new_size += PATH_MAX;
+ new_size = startlen + 1 <= PATH_MAX ? startlen + 1 : PATH_MAX;
rname = xrealloc (rname, new_size);
rname_limit = rname + new_size;
dest = rname + dest_offset;
}
- dest = memcpy (dest, start, end - start);
- dest += end - start;
+ dest = memcpy (dest, start, startlen);
+ dest += startlen;
*dest = '\0';
+ /* If STARTLEN == 0, RNAME ends in '/'; use stat rather than
+ readlink, because readlink might fail with EINVAL without
+ checking whether RNAME sans '/' is valid. */
char discard;
- char *buf = logical ? NULL : areadlink (rname);
+ struct stat st;
+ char *buf = logical || startlen == 0 ? NULL : areadlink (rname);
if (buf)
{
/* A physical traversal and RNAME is a symbolic link. */
@@ -262,15 +267,14 @@ canonicalize_filename_mode (const char *name, canonicalize_mode_t can_mode)
Get the device and inode of the parent directory, as
pre-2017 POSIX says this info is not reliable for
symlinks. */
- dest[- (end - start)] = '\0';
- struct stat st;
+ dest[- startlen] = '\0';
if (stat (*rname ? rname : ".", &st) != 0)
{
saved_errno = errno;
free (buf);
goto error;
}
- dest[- (end - start)] = *start;
+ dest[- startlen] = *start;
/* Detect loops. We cannot use the cycle-check module here,
since it's possible to encounter the same parent
@@ -338,13 +342,16 @@ canonicalize_filename_mode (const char *name, canonicalize_mode_t can_mode)
free (buf);
}
else if (can_exist != CAN_MISSING
- && (!logical || readlink (rname, &discard, 1) < 0))
+ && (startlen == 0
+ ? stat (rname, &st) < 0
+ : !logical && readlink (rname, &discard, 1) < 0))
{
saved_errno = errno;
switch (saved_errno)
{
case EINVAL:
- /* RNAME exists and is not symbolic link. */
+ case EOVERFLOW: /* Possible with stat. */
+ /* RNAME exists and is not a symbolic link. */
break;
case ENOENT:
diff --git a/modules/canonicalize b/modules/canonicalize
index 65c5011f7..ae3fbd3ab 100644
--- a/modules/canonicalize
+++ b/modules/canonicalize
@@ -18,6 +18,7 @@ idx
memmove
nocrash
pathmax
+readlink
stat
sys_stat
xalloc
--
2.27.0
From 7fbedd8f54dc0f8b7dbd940760333520bc92e32f Mon Sep 17 00:00:00 2001
From: Paul Eggert <egg...@cs.ucla.edu>
Date: Sun, 13 Dec 2020 17:32:34 -0800
Subject: [PATCH 5/5] string: port memchr macro to AIX 7.2 XLC
Its <string.h> defines a memchr macro to help inlining.
* lib/string.in.h (memchr): #undef before #defining.
---
ChangeLog | 4 ++++
lib/string.in.h | 1 +
2 files changed, 5 insertions(+)
diff --git a/ChangeLog b/ChangeLog
index b8213ada0..9f9a02160 100644
--- a/ChangeLog
+++ b/ChangeLog
@@ -1,5 +1,9 @@
2020-12-13 Paul Eggert <egg...@cs.ucla.edu>
+ string: port memchr macro to AIX 7.2 XLC
+ Its <string.h> defines a memchr macro to help inlining.
+ * lib/string.in.h (memchr): #undef before #defining.
+
canonicalize: fix AIX test failures
Problem reported by Bruno Haible in:
https://lists.gnu.org/r/bug-gnulib/2020-12/msg00109.html
diff --git a/lib/string.in.h b/lib/string.in.h
index 1bda0fc56..5c3667e8f 100644
--- a/lib/string.in.h
+++ b/lib/string.in.h
@@ -144,6 +144,7 @@ _GL_CXXALIASWARN (memccpy);
#if @GNULIB_MEMCHR@
# if @REPLACE_MEMCHR@
# if !(defined __cplusplus && defined GNULIB_NAMESPACE)
+# undef memchr
# define memchr rpl_memchr
# endif
_GL_FUNCDECL_RPL (memchr, void *, (void const *__s, int __c, size_t __n)
--
2.27.0
