Don't use NGROUPS_MAX define.

getgroups.c

@@ -26,21 +26,16 @@
 
 #include "rsync.h"
 
-#ifndef NGROUPS_MAX
-/* It ought to be defined, but just in case. */
-#  define NGROUPS_MAX 32
-#endif
-
 int
 main(UNUSED(int argc), UNUSED(char *argv[]))
 {
 	int n, i;
-	gid_t list[NGROUPS_MAX];
+	gid_t *list;
 	gid_t gid = MY_GID();
 	int gid_in_list = 0;
 
 #ifdef HAVE_GETGROUPS
-	if ((n = getgroups(NGROUPS_MAX, list)) < 0) {
+	if ((n = getgroups(0, NULL)) < 0) {
 		perror("getgroups");
 		return 1;
 	}
@@ -48,6 +43,17 @@ main(UNUSED(int argc), UNUSED(char *argv[]))
 	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)