include: add getgrgid_r()

configure.ac

@@ -660,6 +660,10 @@ AC_CHECK_FUNCS(pthread_atfork)
 AC_CHECK_FUNCS(statvfs)
 AC_CHECK_LIB(util, openpty)
 AC_CHECK_FUNCS([openpty hasmntopt setmntent endmntent utmpxname])
+AC_CHECK_FUNCS([getgrgid_r],
+	AM_CONDITIONAL(HAVE_GETGRGID_R, true)
+	AC_DEFINE(HAVE_GETGRGID_R,1,[Have getgrgid_r]),
+	AM_CONDITIONAL(HAVE_GETGRGID_R, false))
 AC_CHECK_FUNCS([getline],
 	AM_CONDITIONAL(HAVE_GETLINE, true)
 	AC_DEFINE(HAVE_GETLINE,1,[Have getline]),
@@ -672,6 +676,10 @@ AC_CHECK_FUNCS([fgetln],
 	AM_CONDITIONAL(HAVE_FGETLN, true)
 	AC_DEFINE(HAVE_FGETLN,1,[Have fgetln]),
 	AM_CONDITIONAL(HAVE_FGETLN, false))
+AC_CHECK_FUNCS([pthread_setcancelstate],
+	AM_CONDITIONAL(HAVE_PTHREAD_SETCANCELSTATE, true)
+	AC_DEFINE(HAVE_PTHREAD_SETCANCELSTATE,1,[Have pthread_setcancelstate]),
+	AM_CONDITIONAL(HAVE_PTHREAD_SETCANCELSTATE, false))
 AC_CHECK_FUNCS([strlcpy],
 	AM_CONDITIONAL(HAVE_STRLCPY, true)
 	AC_DEFINE(HAVE_STRLCPY,1,[Have strlcpy]),

src/include/getgrgid_r.h

+/* liblxcapi
+ *
+ * Copyright © 2018 Christian Brauner <christian.brauner@ubuntu.com>.
+ * Copyright © 2018 Canonical Ltd.
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2, as
+ * published by the Free Software Foundation.
+ *
+ * This program 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 General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License along
+ * with this program; if not, write to the Free Software Foundation, Inc.,
+ * 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
+ *
+ * This function has been copied from musl.
+ */
+
+#ifndef _GETGRGID_R_H
+#define _GETGRGID_R_H
+
+#include <stdio.h>
+#include <sys/types.h>
+#include <grp.h>
+
+extern int getgrgid_r(gid_t gid, struct group *gr, char *buf, size_t size,
+		      struct group **res);
+
+#endif /* _GETGRGID_R_H */

src/lxc/Makefile.am

@@ -56,6 +56,10 @@ if !HAVE_GETSUBOPT
 noinst_HEADERS += ../include/getsubopt.h
 endif
 
+if !HAVE_GETGRGID_R
+noinst_HEADERS += ../include/getgrgid_r.h
+endif
+
 sodir=$(libdir)
 
 LSM_SOURCES = \
@@ -148,6 +152,10 @@ if !HAVE_STRLCPY
 liblxc_la_SOURCES += ../include/strlcpy.c ../include/strlcpy.h
 endif
 
+if !HAVE_GETGRGID_R
+liblxc_la_SOURCES += ../include/getgrgid_r.c ../include/getgrgid_r.h
+endif
+
 AM_CFLAGS=-DLXCROOTFSMOUNT=\"$(LXCROOTFSMOUNT)\" \
 	-DLXCPATH=\"$(LXCPATH)\" \
 	-DLXC_GLOBAL_CONF=\"$(LXC_GLOBAL_CONF)\" \
@@ -304,6 +312,10 @@ if !HAVE_STRLCPY
 init_lxc_static_SOURCES += ../include/strlcpy.c ../include/strlcpy.h
 endif
 
+if !HAVE_GETGRGID_R
+liblxc_la_SOURCES += ../include/getgrgid_r.c ../include/getgrgid_r.h
+endif
+
 init_lxc_static_LDFLAGS = -all-static
 init_lxc_static_LDADD = @CAP_LIBS@
 init_lxc_static_CFLAGS = $(AM_CFLAGS) -DNO_LXC_CONF