Merge from Gnulib

This incorporates:
2017-11-11 faccessat: port to macOS (Bug#29231)
2017-11-05 fstatat: pacify GCC on unusual platform
* build-aux/config.guess, build-aux/config.sub:
* doc/misc/texinfo.tex, lib/faccessat.c, lib/fstatat.c:
* lib/unistd.in.h, m4/faccessat.m4, m4/unistd_h.m4:
Copy from Gnulib.
* lib/gnulib.mk.in, m4/gnulib-comp.m4: Regenerate.

4 files changed, 70 insertions, 10 deletions

diff --git a/lib/faccessat.c b/lib/faccessat.c
index 6cf9c99df20..fa9235820dc 100644
--- a/lib/faccessat.c
+++ b/lib/faccessat.c
@@ -16,10 +16,31 @@
 
 /* written by Eric Blake */
 
+/* If the user's config.h happens to include <unistd.h>, let it include only
+   the system's <unistd.h> here, so that orig_faccessat doesn't recurse to
+   rpl_faccessat.  */
+#define _GL_INCLUDING_UNISTD_H
 #include <config.h>
 
 #include <unistd.h>
+#include <errno.h>
 #include <fcntl.h>
+#include <string.h>
+#include <sys/stat.h>
+#undef _GL_INCLUDING_UNISTD_H
+
+#if HAVE_FACCESSAT
+static int
+orig_faccessat (int fd, char const *name, int mode, int flag)
+{
+  return faccessat (fd, name, mode, flag);
+}
+#endif
+
+/* Write "unistd.h" here, not <unistd.h>, otherwise OSF/1 5.1 DTK cc
+   eliminates this include because of the preliminary #include <unistd.h>
+   above.  */
+#include "unistd.h"
 
 #ifndef HAVE_ACCESS
 /* Mingw lacks access, but it also lacks real vs. effective ids, so
@@ -28,6 +49,29 @@
 # define access euidaccess
 #endif
 
+#if HAVE_FACCESSAT
+
+int
+rpl_faccessat (int fd, char const *file, int mode, int flag)
+{
+  int result = orig_faccessat (fd, file, mode, flag);
+
+  if (result == 0 && file[strlen (file) - 1] == '/')
+    {
+      struct stat st;
+      result = fstatat (fd, file, &st, 0);
+      if (result == 0 && !S_ISDIR (st.st_mode))
+        {
+          errno = ENOTDIR;
+          return -1;
+        }
+    }
+
+  return result;
+}
+
+#else /* !HAVE_FACCESSAT */
+
 /* Invoke access or euidaccess on file, FILE, using mode MODE, in the directory
    open on descriptor FD.  If possible, do it without changing the
    working directory.  Otherwise, resort to using save_cwd/fchdir, then
@@ -36,10 +80,12 @@
    Note that this implementation only supports AT_EACCESS, although some
    native versions also support AT_SYMLINK_NOFOLLOW.  */
 
-#define AT_FUNC_NAME faccessat
-#define AT_FUNC_F1 euidaccess
-#define AT_FUNC_F2 access
-#define AT_FUNC_USE_F1_COND AT_EACCESS
-#define AT_FUNC_POST_FILE_PARAM_DECLS , int mode, int flag
-#define AT_FUNC_POST_FILE_ARGS        , mode
-#include "at-func.c"
+# define AT_FUNC_NAME faccessat
+# define AT_FUNC_F1 euidaccess
+# define AT_FUNC_F2 access
+# define AT_FUNC_USE_F1_COND AT_EACCESS
+# define AT_FUNC_POST_FILE_PARAM_DECLS , int mode, int flag
+# define AT_FUNC_POST_FILE_ARGS        , mode
+# include "at-func.c"
+
+#endif
diff --git a/lib/fstatat.c b/lib/fstatat.c
index 67e48d95d71..294861f51b1 100644
--- a/lib/fstatat.c
+++ b/lib/fstatat.c
@@ -28,7 +28,7 @@
 #include <sys/stat.h>
 #undef __need_system_sys_stat_h
 
-#if HAVE_FSTATAT
+#if HAVE_FSTATAT && HAVE_WORKING_FSTATAT_ZERO_FLAG
 static int
 orig_fstatat (int fd, char const *filename, struct stat *buf, int flags)
 {
diff --git a/lib/gnulib.mk.in b/lib/gnulib.mk.in
index 0f795b3d820..c510a0e55c0 100644
--- a/lib/gnulib.mk.in
+++ b/lib/gnulib.mk.in
@@ -689,6 +689,7 @@ REPLACE_DIRFD = @REPLACE_DIRFD@
 REPLACE_DPRINTF = @REPLACE_DPRINTF@
 REPLACE_DUP = @REPLACE_DUP@
 REPLACE_DUP2 = @REPLACE_DUP2@
+REPLACE_FACCESSAT = @REPLACE_FACCESSAT@
 REPLACE_FCHOWNAT = @REPLACE_FCHOWNAT@
 REPLACE_FCLOSE = @REPLACE_FCLOSE@
 REPLACE_FCNTL = @REPLACE_FCNTL@
@@ -2986,6 +2987,7 @@ unistd.h: unistd.in.h $(top_builddir)/config.status $(CXXDEFS_H) $(ARG_NONNULL_H
 	      -e 's|@''REPLACE_CLOSE''@|$(REPLACE_CLOSE)|g' \
 	      -e 's|@''REPLACE_DUP''@|$(REPLACE_DUP)|g' \
 	      -e 's|@''REPLACE_DUP2''@|$(REPLACE_DUP2)|g' \
+	      -e 's|@''REPLACE_FACCESSAT''@|$(REPLACE_FACCESSAT)|g' \
 	      -e 's|@''REPLACE_FCHOWNAT''@|$(REPLACE_FCHOWNAT)|g' \
 	      -e 's|@''REPLACE_FTRUNCATE''@|$(REPLACE_FTRUNCATE)|g' \
 	      -e 's|@''REPLACE_GETCWD''@|$(REPLACE_GETCWD)|g' \
diff --git a/lib/unistd.in.h b/lib/unistd.in.h
index ca8090a3526..91447835811 100644
--- a/lib/unistd.in.h
+++ b/lib/unistd.in.h
@@ -461,13 +461,25 @@ _GL_WARN_ON_USE (euidaccess, "euidaccess is unportable - "
 
 
 #if @GNULIB_FACCESSAT@
-# if !@HAVE_FACCESSAT@
+# if @REPLACE_FACCESSAT@
+#  if !(defined __cplusplus && defined GNULIB_NAMESPACE)
+#   undef faccessat
+#   define faccessat rpl_faccessat
+#  endif
+_GL_FUNCDECL_RPL (faccessat, int,
+                  (int fd, char const *name, int mode, int flag)
+                  _GL_ARG_NONNULL ((2)));
+_GL_CXXALIAS_RPL (faccessat, int,
+                  (int fd, char const *name, int mode, int flag));
+# else
+#  if !@HAVE_FACCESSAT@
 _GL_FUNCDECL_SYS (faccessat, int,
                   (int fd, char const *file, int mode, int flag)
                   _GL_ARG_NONNULL ((2)));
-# endif
+#  endif
 _GL_CXXALIAS_SYS (faccessat, int,
                   (int fd, char const *file, int mode, int flag));
+# endif
 _GL_CXXALIASWARN (faccessat);
 #elif defined GNULIB_POSIXCHECK
 # undef faccessat