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>

28 files changed, 1720 insertions, 1 deletions

diff --git a/nss/Makefile b/nss/Makefile
index 32764b74c0..baf7d9d0ab 100644
--- a/nss/Makefile
+++ b/nss/Makefile
@@ -23,6 +23,7 @@ subdir	:= nss
 include ../Makeconfig
 
 headers := \
+  grp.h \
   nss.h \
   # headers
 
@@ -50,6 +51,34 @@ routines = \
   valid_list_field \
   # routines
 
+# grp routines:
+routines += \
+  fgetgrent \
+  fgetgrent_r \
+  getgrent \
+  getgrent_r \
+  getgrgid \
+  getgrgid_r \
+  getgrnam \
+  getgrnam_r \
+  grp-merge \
+  initgroups \
+  putgrent \
+  # routines
+
+ifeq ($(have-thread-library),yes)
+CFLAGS-fgetgrent.c += -fexceptions
+CFLAGS-fgetgrent_r.c += -fexceptions $(libio-mtsafe)
+CFLAGS-getgrent.c += -fexceptions
+CFLAGS-getgrent_r.c += -fexceptions
+CFLAGS-getgrgid.c += -fexceptions
+CFLAGS-getgrgid_r.c += -fexceptions
+CFLAGS-getgrnam.c += -fexceptions
+CFLAGS-getgrnam_r.c += -fexceptions
+CFLAGS-initgroups.c += -fexceptions
+CFLAGS-putgrent.c += -fexceptions $(libio-mtsafe)
+endif
+
 # These are the databases that go through nss dispatch.
 # Caution: if you add a database here, you must add its real name
 # in databases.def, too.
@@ -88,6 +117,7 @@ tests := \
   bug17079 \
   test-digits-dots \
   test-netdb \
+  testgrp \
   tst-nss-getpwent \
   tst-nss-hash \
   tst-nss-test1 \
@@ -95,11 +125,14 @@ tests := \
   tst-nss-test4 \
   tst-nss-test5 \
   tst-nss-test_errno \
+  tst-putgrent \
   # tests
 
 xtests = bug-erange
 
 tests-container := \
+  tst-initgroups1 \
+  tst-initgroups2 \
   tst-nss-compat1 \
   tst-nss-db-endgrent \
   tst-nss-db-endpwent \
@@ -112,13 +145,21 @@ tests-container := \
   tst-reload2 \
   # tests-container
 
-# Tests which need libdl
 ifeq (yes,$(build-shared))
+# Tests which need libdl
 tests += tst-nss-files-hosts-erange
 tests += tst-nss-files-hosts-multi
 tests += tst-nss-files-hosts-getent
 tests += tst-nss-files-alias-leak
 tests += tst-nss-files-alias-truncated
+# tst_fgetgrent currently only works with shared libraries
+test-srcs :=  tst_fgetgrent
+ifeq ($(run-built-tests),yes)
+tests-special += $(objpfx)tst_fgetgrent.out
+$(objpfx)tst_fgetgrent.out: tst_fgetgrent.sh $(objpfx)tst_fgetgrent
+	$(SHELL) $< $(common-objpfx) '$(test-program-prefix)'; \
+	$(evaluate-test)
+endif
 endif
 
 # If we have a thread library then we can test cancellation against
diff --git a/nss/Versions b/nss/Versions
index e551524aa9..5401829911 100644
--- a/nss/Versions
+++ b/nss/Versions
@@ -5,10 +5,38 @@ libc {
     # Functions exported as no-op compat symbols.
     __nss_passwd_lookup; __nss_group_lookup; __nss_hosts_lookup; __nss_next;
     __nss_database_lookup;
+
+    # e*
+    endgrent;
+
+    # f*
+    fgetgrent; fgetgrent_r;
+
+    # g*
+    getgrent; getgrent_r; getgrgid; getgrgid_r; getgrnam; getgrnam_r;
+    getgroups;
+
+    # i*
+    initgroups;
+
+    # s*
+    setgrent;
+  }
+  GLIBC_2.1 {
+    # p*
+    putgrent;
+  }
+  GLIBC_2.1.2 {
+    # g*
+    getgrent_r; getgrgid_r; getgrnam_r;
   }
   GLIBC_2.2.2 {
     __nss_hostname_digits_dots;
   }
+  GLIBC_2.2.4 {
+    # g*
+    getgrouplist;
+  }
   GLIBC_2.27 {
   }
   GLIBC_PRIVATE {
@@ -107,6 +135,8 @@ libc {
     _nss_files_initgroups_dyn;
 
     _nss_files_init;
+
+    __merge_grp; __copy_grp;
   }
 }
 
diff --git a/nss/fgetgrent.c b/nss/fgetgrent.c
new file mode 100644
index 0000000000..2e7c7fe5fb
--- /dev/null
+++ b/nss/fgetgrent.c
@@ -0,0 +1,87 @@
+/* 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/>.  */
+
+#include <errno.h>
+#include <grp.h>
+#include <libc-lock.h>
+#include <stdio.h>
+#include <stdlib.h>
+#include <set-freeres.h>
+
+
+/* We need to protect the dynamic buffer handling.  */
+__libc_lock_define_initialized (static, lock);
+
+static char *buffer;
+
+/* Read one entry from the given stream.  */
+struct group *
+fgetgrent (FILE *stream)
+{
+  static size_t buffer_size;
+  static struct group resbuf;
+  fpos_t pos;
+  struct group *result;
+  int save;
+
+  if (__builtin_expect (fgetpos (stream, &pos), 0) != 0)
+    return NULL;
+
+  /* Get lock.  */
+  __libc_lock_lock (lock);
+
+  /* Allocate buffer if not yet available.  */
+  if (buffer == NULL)
+    {
+      buffer_size = NSS_BUFLEN_GROUP;
+      buffer = malloc (buffer_size);
+    }
+
+  while (buffer != NULL
+	 && (__fgetgrent_r (stream, &resbuf, buffer, buffer_size, &result)
+	     == ERANGE))
+    {
+      char *new_buf;
+      buffer_size += NSS_BUFLEN_GROUP;
+      new_buf = realloc (buffer, buffer_size);
+      if (__glibc_unlikely (new_buf == NULL))
+	{
+	  /* We are out of memory.  Free the current buffer so that the
+	     process gets a chance for a normal termination.  */
+	  save = errno;
+	  free (buffer);
+	  __set_errno (save);
+	}
+      buffer = new_buf;
+
+      /* Reset the stream.  */
+      if (fsetpos (stream, &pos) != 0)
+	buffer = NULL;
+    }
+
+  if (buffer == NULL)
+    result = NULL;
+
+  /* Release lock.  Preserve error value.  */
+  save = errno;
+  __libc_lock_unlock (lock);
+  __set_errno (save);
+
+  return result;
+}
+
+weak_alias (buffer, __libc_fgetgrent_freemem_ptr)
diff --git a/nss/fgetgrent_r.c b/nss/fgetgrent_r.c
new file mode 100644
index 0000000000..5ce70230f1
--- /dev/null
+++ b/nss/fgetgrent_r.c
@@ -0,0 +1,65 @@
+/* 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/>.  */
+
+#include <ctype.h>
+#include <errno.h>
+#include <grp.h>
+#include <stdio.h>
+
+/* Define a line parsing function using the common code
+   used in the nss_files module.  */
+
+#define STRUCTURE	group
+#define ENTNAME		grent
+struct grent_data {};
+
+#define TRAILING_LIST_MEMBER		gr_mem
+#define TRAILING_LIST_SEPARATOR_P(c)	((c) == ',')
+#include <nss/nss_files/files-parse.c>
+LINE_PARSER
+(,
+ STRING_FIELD (result->gr_name, ISCOLON, 0);
+ if (line[0] == '\0'
+     && (result->gr_name[0] == '+' || result->gr_name[0] == '-'))
+   {
+     result->gr_passwd = NULL;
+     result->gr_gid = 0;
+   }
+ else
+   {
+     STRING_FIELD (result->gr_passwd, ISCOLON, 0);
+     if (result->gr_name[0] == '+' || result->gr_name[0] == '-')
+       INT_FIELD_MAYBE_NULL (result->gr_gid, ISCOLON, 0, 10, , 0)
+     else
+       INT_FIELD (result->gr_gid, ISCOLON, 0, 10,)
+   }
+ )
+
+
+/* Read one entry from the given stream.  */
+int
+__fgetgrent_r (FILE *stream, struct group *resbuf, char *buffer, size_t buflen,
+	       struct group **result)
+{
+  int ret = __nss_fgetent_r (stream, resbuf, buffer, buflen, parse_line);
+  if (ret == 0)
+    *result = resbuf;
+  else
+    *result = NULL;
+  return ret;
+}
+weak_alias (__fgetgrent_r, fgetgrent_r)
diff --git a/nss/getgrent.c b/nss/getgrent.c
new file mode 100644
index 0000000000..6e09987318
--- /dev/null
+++ b/nss/getgrent.c
@@ -0,0 +1,28 @@
+/* Copyright (C) 1996-2023 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/>.  */
+
+#include <grp.h>
+
+
+#define LOOKUP_TYPE	struct group
+#define SETFUNC_NAME	setgrent
+#define	GETFUNC_NAME	getgrent
+#define	ENDFUNC_NAME	endgrent
+#define DATABASE_NAME	group
+#define BUFLEN		NSS_BUFLEN_GROUP
+
+#include "../nss/getXXent.c"
diff --git a/nss/getgrent_r.c b/nss/getgrent_r.c
new file mode 100644
index 0000000000..ea3d0e89c1
--- /dev/null
+++ b/nss/getgrent_r.c
@@ -0,0 +1,28 @@
+/* Copyright (C) 1996-2023 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/>.  */
+
+#include <grp.h>
+
+
+#define LOOKUP_TYPE	struct group
+#define SETFUNC_NAME	setgrent
+#define	GETFUNC_NAME	getgrent
+#define	ENDFUNC_NAME	endgrent
+#define DATABASE_NAME	group
+#define BUFLEN		NSS_BUFLEN_GROUP
+
+#include "../nss/getXXent_r.c"
diff --git a/nss/getgrgid.c b/nss/getgrgid.c
new file mode 100644
index 0000000000..db50f8fdac
--- /dev/null
+++ b/nss/getgrgid.c
@@ -0,0 +1,28 @@
+/* Copyright (C) 1996-2023 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/>.  */
+
+#include <grp.h>
+
+
+#define LOOKUP_TYPE	struct group
+#define FUNCTION_NAME	getgrgid
+#define DATABASE_NAME	group
+#define ADD_PARAMS	gid_t gid
+#define ADD_VARIABLES	gid
+#define BUFLEN		NSS_BUFLEN_GROUP
+
+#include "../nss/getXXbyYY.c"
diff --git a/nss/getgrgid_r.c b/nss/getgrgid_r.c
new file mode 100644
index 0000000000..dab5f85ef3
--- /dev/null
+++ b/nss/getgrgid_r.c
@@ -0,0 +1,31 @@
+/* Copyright (C) 1996-2023 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/>.  */
+
+#include <grp.h>
+
+#include <grp-merge.h>
+
+#define LOOKUP_TYPE	struct group
+#define FUNCTION_NAME	getgrgid
+#define DATABASE_NAME	group
+#define ADD_PARAMS	gid_t gid
+#define ADD_VARIABLES	gid
+#define BUFLEN		NSS_BUFLEN_GROUP
+#define DEEPCOPY_FN	__copy_grp
+#define MERGE_FN	__merge_grp
+
+#include <nss/getXXbyYY_r.c>
diff --git a/nss/getgrnam.c b/nss/getgrnam.c
new file mode 100644
index 0000000000..98d637b2bc
--- /dev/null
+++ b/nss/getgrnam.c
@@ -0,0 +1,28 @@
+/* Copyright (C) 1996-2023 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/>.  */
+
+#include <grp.h>
+
+
+#define LOOKUP_TYPE	struct group
+#define FUNCTION_NAME	getgrnam
+#define DATABASE_NAME	group
+#define ADD_PARAMS	const char *name
+#define ADD_VARIABLES	name
+#define BUFLEN		NSS_BUFLEN_GROUP
+
+#include "../nss/getXXbyYY.c"
diff --git a/nss/getgrnam_r.c b/nss/getgrnam_r.c
new file mode 100644
index 0000000000..ed5649c8d8
--- /dev/null
+++ b/nss/getgrnam_r.c
@@ -0,0 +1,31 @@
+/* Copyright (C) 1996-2023 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/>.  */
+
+#include <grp.h>
+
+#include <grp-merge.h>
+
+#define LOOKUP_TYPE	struct group
+#define FUNCTION_NAME	getgrnam
+#define DATABASE_NAME	group
+#define ADD_PARAMS	const char *name
+#define ADD_VARIABLES	name
+
+#define DEEPCOPY_FN	__copy_grp
+#define MERGE_FN	__merge_grp
+
+#include <nss/getXXbyYY_r.c>
diff --git a/nss/grp-merge.c b/nss/grp-merge.c
new file mode 100644
index 0000000000..991abf0252
--- /dev/null
+++ b/nss/grp-merge.c
@@ -0,0 +1,200 @@