posix: Sync glob with gnulib [BZ #1062]

This patch syncs posix/glob.c implementation with gnulib version
b5ec983 (glob: simplify symlink detection).  The only difference
to gnulib code is

  * DT_UNKNOWN, DT_DIR, and DT_LNK definition in the case there
    were not already defined.  Gnulib code which uses
    HAVE_STRUCT_DIRENT_D_TYPE will redefine them wrongly because
    GLIBC does not define HAVE_STRUCT_DIRENT_D_TYPE.  Instead
    the patch check for each definition instead.

Also, the patch requires additional globfree and globfree64 files
for compatibility version on some architectures.  Also the code
simplification leads to not macro simplification (not need for
NO_GLOB_PATTERN_P anymore).

Checked on x86_64-linux-gnu and on a build using build-many-glibcs.py
for all major architectures.

	[BZ #1062]
	* posix/Makefile (routines): Add globfree, globfree64, and
	glob_pattern_p.
	* posix/flexmember.h: New file.
	* posix/glob_internal.h: Likewise.
	* posix/glob_pattern_p.c: Likewise.
	* posix/globfree.c: Likewise.
	* posix/globfree64.c: Likewise.
	* sysdeps/gnu/globfree64.c: Likewise.
	* sysdeps/unix/sysv/linux/alpha/globfree.c: Likewise.
	* sysdeps/unix/sysv/linux/mips/mips64/n64/globfree64.c: Likewise.
	* sysdeps/unix/sysv/linux/oldglob.c: Likewise.
	* sysdeps/unix/sysv/linux/wordsize-64/globfree64.c: Likewise.
	* sysdeps/unix/sysv/linux/x86_64/x32/globfree.c: Likewise.
	* sysdeps/wordsize-64/globfree.c: Likewise.
	* sysdeps/wordsize-64/globfree64.c: Likewise.
	* posix/glob.c (HAVE_CONFIG_H): Use !_LIBC instead.
	[NDEBUG): Remove comments.
	(GLOB_ONLY_P, _AMIGA, VMS): Remove define.
	(dirent_type): New type.  Use uint_fast8_t not
	uint8_t, as C99 does not require uint8_t.
	(DT_UNKNOWN, DT_DIR, DT_LNK): New macros.
	(struct readdir_result): Use dirent_type.  Do not define skip_entry
	unless it is needed; this saves a byte on platforms lacking d_ino.
	(readdir_result_type, readdir_result_skip_entry):
	New functions, replacing ...
	(readdir_result_might_be_symlink, readdir_result_might_be_dir):
	 these functions, which were removed.  This makes the callers
	easier to read.  All callers changed.
	(D_INO_TO_RESULT): Now empty if there is no d_ino.
	(size_add_wrapv, glob_use_alloca): New static functions.
	(glob, glob_in_dir): Check for size_t overflow in several places,
	and fix some size_t checks that were not quite right.
	Remove old code using SHELL since Bash no longer
	uses this.
	(glob, prefix_array): Separate MS code better.
	(glob_in_dir): Remove old Amiga and VMS code.
	(globfree, __glob_pattern_type, __glob_pattern_p): Move to
	separate files.
	(glob_in_dir): Do not rely on undefined behavior in accessing
	struct members beyond their bounds.  Use a flexible array member
	instead
	(link_stat): Rename from link_exists2_p and return -1/0 instead of
	0/1.  Caller changed.
	(glob): Fix memory leaks.
	* posix/glob64 (globfree64): Move to separate file.
	* sysdeps/gnu/glob64.c (NO_GLOB_PATTERN_P): Remove define.
	(globfree64): Remove hidden alias.
	* sysdeps/unix/sysv/linux/Makefile (sysdeps_routines): Add
	oldglob.
	* sysdeps/unix/sysv/linux/alpha/glob.c (__new_globfree): Move to
	separate file.
	* sysdeps/unix/sysv/linux/i386/glob64.c (NO_GLOB_PATTERN_P): Remove
	define.
	Move compat code to separate file.
	* sysdeps/wordsize-64/glob.c (globfree): Move definitions to
	separate file.

1 files changed, 45 insertions, 0 deletions

diff --git a/posix/flexmember.h b/posix/flexmember.h
new file mode 100644
index 0000000000..107c1f09e9
--- /dev/null
+++ b/posix/flexmember.h
@@ -0,0 +1,45 @@
+/* Sizes of structs with flexible array members.
+
+   Copyright 2016-2017 Free Software Foundation, Inc.
+
+   This file is part of the GNU C Library.
+
+   The GNU C Library is free software; you can redistribute it and/or
+   modify it under the terms of the GNU Lesser General Public
+   License as published by the Free Software Foundation; either
+   version 2.1 of the License, or (at your option) any later version.
+
+   The GNU C Library is distributed in the hope that it will be useful,
+   but WITHOUT ANY WARRANTY; without even the implied warranty of
+   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+   Lesser General Public License for more details.
+
+   You should have received a copy of the GNU Lesser General Public
+   License along with the GNU C Library; if not, see
+   <http://www.gnu.org/licenses/>.
+
+   Written by Paul Eggert.  */
+
+#include <stddef.h>
+
+/* Nonzero multiple of alignment of TYPE, suitable for FLEXSIZEOF below.
+   On older platforms without _Alignof, use a pessimistic bound that is
+   safe in practice even if FLEXIBLE_ARRAY_MEMBER is 1.
+   On newer platforms, use _Alignof to get a tighter bound.  */
+
+#if !defined __STDC_VERSION__ || __STDC_VERSION__ < 201112
+# define FLEXALIGNOF(type) (sizeof (type) & ~ (sizeof (type) - 1))
+#else
+# define FLEXALIGNOF(type) _Alignof (type)
+#endif
+
+/* Upper bound on the size of a struct of type TYPE with a flexible
+   array member named MEMBER that is followed by N bytes of other data.
+   This is not simply sizeof (TYPE) + N, since it may require
+   alignment on unusually picky C11 platforms, and
+   FLEXIBLE_ARRAY_MEMBER may be 1 on pre-C11 platforms.
+   Yield a value less than N if and only if arithmetic overflow occurs.  */
+
+#define FLEXSIZEOF(type, member, n) \
+   ((offsetof (type, member) + FLEXALIGNOF (type) - 1 + (n)) \
+    & ~ (FLEXALIGNOF (type) - 1))