1 files changed, 61 insertions, 0 deletions
diff --git a/getgroups.c b/getgroups.c
new file mode 100644
index 0000000..8a37ed0
--- /dev/null
+++ b/getgroups.c
@@ -0,0 +1,61 @@
+/*
+ * Print out the gids of all groups for the current user.  This is like
+ * `id -G` on Linux, but it's too hard to find a portable equivalent.
+ *
+ * Copyright (C) 2002 Martin Pool
+ * Copyright (C) 2003-2020 Wayne Davison
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 3 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, visit the http://fsf.org website.
+ */
+
+#include "rsync.h"
+
+ int main(UNUSED(int argc), UNUSED(char *argv[]))
+{
+	int n, i;
+	gid_t *list;
+	gid_t gid = MY_GID();
+	int gid_in_list = 0;
+
+#ifdef HAVE_GETGROUPS
+	if ((n = getgroups(0, NULL)) < 0) {
+		perror("getgroups");
+		return 1;
+	}
+#else
+	n = 0;
+#endif
+
+	list = (gid_t*)malloc(sizeof (gid_t) * (n + 1));
+	if (!list) {
+		fprintf(stderr, "out of memory!\n");
+		exit(1);
+	}
+
+#ifdef HAVE_GETGROUPS
+	if (n > 0)
+		n = getgroups(n, list);
+#endif
+
+	for (i = 0; i < n; i++)  {
+		printf("%lu ", (unsigned long)list[i]);
+		if (list[i] == gid)
+			gid_in_list = 1;
+	}
+	/* The default gid might not be in the list on some systems. */
+	if (!gid_in_list)
+		printf("%lu", (unsigned long)gid);
+	printf("\n");
+
+	return 0;
+}