Remove 'grp' and merge into 'nss' and 'posix'

The majority of grp routines are entry points for nss functionality.
This commit removes the 'grp' subdirectory and moves all nss-relevant
functionality and all tests to 'nss', and the 'setgroups' stub into
'posix' (alongside the 'getgroups' stub).  References to grp/ are
accordingly changed.  In addition, compat-initgroups.c, a fallback
implementation of initgroups is renamed to initgroups-fallback.c so that
the build system does not confuse it for nss_compat/compat-initgroups.c.

Build time improves very slightly; e.g. down from an average of 45.5s to
44.5s on an 8-thread mobile x86_64 CPU.
Reviewed-by: Adhemerval Zanella  <adhemerval.zanella@linaro.org>

1 files changed, 207 insertions, 0 deletions

diff --git a/nss/grp.h b/nss/grp.h
new file mode 100644
index 0000000..c889647
--- /dev/null
+++ b/nss/grp.h
@@ -0,0 +1,207 @@
+/* Copyright (C) 1991-2023 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
+   <https://www.gnu.org/licenses/>.  */
+
+/*
+ *	POSIX Standard: 9.2.1 Group Database Access	<grp.h>
+ */
+
+#ifndef	_GRP_H
+#define	_GRP_H	1
+
+#include <features.h>
+
+__BEGIN_DECLS
+
+#include <bits/types.h>
+
+#define __need_size_t
+#include <stddef.h>
+
+
+/* For the Single Unix specification we must define this type here.  */
+#if (defined __USE_XOPEN || defined __USE_XOPEN2K) && !defined __gid_t_defined
+typedef __gid_t gid_t;
+# define __gid_t_defined
+#endif
+
+/* The group structure.	 */
+struct group
+  {
+    char *gr_name;		/* Group name.	*/
+    char *gr_passwd;		/* Password.	*/
+    __gid_t gr_gid;		/* Group ID.	*/
+    char **gr_mem;		/* Member list.	*/
+  };
+
+
+#ifdef __USE_MISC
+# include <bits/types/FILE.h>
+#endif
+
+
+#if defined __USE_MISC || defined __USE_XOPEN_EXTENDED
+/* Rewind the group-file stream.
+
+   This function is a possible cancellation point and therefore not
+   marked with __THROW.  */
+extern void setgrent (void);
+
+/* Close the group-file stream.
+
+   This function is a possible cancellation point and therefore not
+   marked with __THROW.  */
+extern void endgrent (void);
+
+/* Read an entry from the group-file stream, opening it if necessary.
+
+   This function is a possible cancellation point and therefore not
+   marked with __THROW.  */
+extern struct group *getgrent (void);
+#endif
+
+#ifdef	__USE_MISC
+/* Read a group entry from STREAM.
+
+   This function is not part of POSIX and therefore no official
+   cancellation point.  But due to similarity with an POSIX interface
+   or due to the implementation it is a cancellation point and
+   therefore not marked with __THROW.  */
+extern struct group *fgetgrent (FILE *__stream);
+#endif
+
+#ifdef __USE_GNU
+/* Write the given entry onto the given stream.
+
+   This function is not part of POSIX and therefore no official
+   cancellation point.  But due to similarity with an POSIX interface
+   or due to the implementation it is a cancellation point and
+   therefore not marked with __THROW.  */
+extern int putgrent (const struct group *__restrict __p,
+		     FILE *__restrict __f);
+#endif
+
+/* Search for an entry with a matching group ID.
+
+   This function is a possible cancellation point and therefore not
+   marked with __THROW.  */
+extern struct group *getgrgid (__gid_t __gid);
+
+/* Search for an entry with a matching group name.
+
+   This function is a possible cancellation point and therefore not
+   marked with __THROW.  */
+extern struct group *getgrnam (const char *__name);
+
+#ifdef __USE_POSIX
+
+# ifdef __USE_MISC
+/* Reasonable value for the buffer sized used in the reentrant
+   functions below.  But better use `sysconf'.  */
+#  define NSS_BUFLEN_GROUP	1024
+# endif
+
+/* Reentrant versions of some of the functions above.
+
+   PLEASE NOTE: the `getgrent_r' function is not (yet) standardized.
+   The interface may change in later versions of this library.  But
+   the interface is designed following the principals used for the
+   other reentrant functions so the chances are good this is what the
+   POSIX people would choose.
+
+   This function is not part of POSIX and therefore no official
+   cancellation point.  But due to similarity with an POSIX interface
+   or due to the implementation it is a cancellation point and
+   therefore not marked with __THROW.  */
+
+# ifdef __USE_GNU
+extern int getgrent_r (struct group *__restrict __resultbuf,
+		       char *__restrict __buffer, size_t __buflen,
+		       struct group **__restrict __result)
+	__attr_access ((__write_only__, 2, 3));
+# endif
+
+/* Search for an entry with a matching group ID.
+
+   This function is a possible cancellation point and therefore not
+   marked with __THROW.  */
+extern int getgrgid_r (__gid_t __gid, struct group *__restrict __resultbuf,
+		       char *__restrict __buffer, size_t __buflen,
+		       struct group **__restrict __result)
+	__attr_access ((__write_only__, 3, 4));
+
+/* Search for an entry with a matching group name.
+
+   This function is a possible cancellation point and therefore not
+   marked with __THROW.  */
+extern int getgrnam_r (const char *__restrict __name,
+		       struct group *__restrict __resultbuf,
+		       char *__restrict __buffer, size_t __buflen,
+		       struct group **__restrict __result)
+	__attr_access ((__write_only__, 3, 4));
+
+# ifdef	__USE_MISC
+/* Read a group entry from STREAM.  This function is not standardized
+   an probably never will.
+
+   This function is not part of POSIX and therefore no official
+   cancellation point.  But due to similarity with an POSIX interface
+   or due to the implementation it is a cancellation point and
+   therefore not marked with __THROW.  */
+extern int fgetgrent_r (FILE *__restrict __stream,
+			struct group *__restrict __resultbuf,
+			char *__restrict __buffer, size_t __buflen,
+			struct group **__restrict __result)
+	__attr_access ((__write_only__, 3, 4));
+# endif
+
+#endif	/* POSIX or reentrant */
+
+
+#ifdef	__USE_MISC
+
+# define __need_size_t
+# include <stddef.h>
+
+/* Set the group set for the current user to GROUPS (N of them).  */
+extern int setgroups (size_t __n, const __gid_t *__groups) __THROW;
+
+/* Store at most *NGROUPS members of the group set for USER into
+   *GROUPS.  Also include GROUP.  The actual number of groups found is
+   returned in *NGROUPS.  Return -1 if the if *NGROUPS is too small.
+
+   This function is not part of POSIX and therefore no official
+   cancellation point.  But due to similarity with an POSIX interface
+   or due to the implementation it is a cancellation point and
+   therefore not marked with __THROW.  */
+extern int getgrouplist (const char *__user, __gid_t __group,
+			 __gid_t *__groups, int *__ngroups);
+
+/* Initialize the group set for the current user
+   by reading the group database and using all groups
+   of which USER is a member.  Also include GROUP.
+
+   This function is not part of POSIX and therefore no official
+   cancellation point.  But due to similarity with an POSIX interface
+   or due to the implementation it is a cancellation point and
+   therefore not marked with __THROW.  */
+extern int initgroups (const char *__user, __gid_t __group);
+
+#endif /* Use misc.  */
+
+__END_DECLS
+
+#endif /* grp.h  */