tests: extend test coverage of setresgid32 syscall

* tests/setresgid32.c: New file.
* tests/setresgid32.test: New test.
* tests/.gitignore: Add setresgid32.
* tests/Makefile.am (check_PROGRAMS): Likewise.
(DECODER_TESTS): Add setresgid32.test.
diff --git a/tests/.gitignore b/tests/.gitignore
index c2ac5c8..3ef4062 100644
--- a/tests/.gitignore
+++ b/tests/.gitignore
@@ -148,6 +148,7 @@
 setregid
 setregid32
 setresgid
+setresgid32
 setresuid
 setresuid32
 setreuid
diff --git a/tests/Makefile.am b/tests/Makefile.am
index 250081d..cf2027a 100644
--- a/tests/Makefile.am
+++ b/tests/Makefile.am
@@ -198,6 +198,7 @@
 	setregid \
 	setregid32 \
 	setresgid \
+	setresgid32 \
 	setresuid \
 	setresuid32 \
 	setreuid \
@@ -416,6 +417,7 @@
 	setregid.test \
 	setregid32.test \
 	setresgid.test \
+	setresgid32.test \
 	setresuid.test \
 	setresuid32.test \
 	setreuid.test \
diff --git a/tests/setresgid32.c b/tests/setresgid32.c
new file mode 100644
index 0000000..29a8042
--- /dev/null
+++ b/tests/setresgid32.c
@@ -0,0 +1,17 @@
+#include "tests.h"
+#include <sys/syscall.h>
+
+#ifdef __NR_setresgid32
+
+# define SYSCALL_NR	__NR_setresgid32
+# define SYSCALL_NAME	"setresgid32"
+# define UGID_TYPE	int
+# define GETUGID	getegid()
+# define CHECK_OVERFLOWUGID(arg)
+# include "setresugid.c"
+
+#else
+
+SKIP_MAIN_UNDEFINED("__NR_setresgid32")
+
+#endif
diff --git a/tests/setresgid32.test b/tests/setresgid32.test
new file mode 100755
index 0000000..528b2c9
--- /dev/null
+++ b/tests/setresgid32.test
@@ -0,0 +1,6 @@
+#!/bin/sh
+
+# Check setresgid32 syscall decoding.
+
+. "${srcdir=.}/init.sh"
+run_strace_match_diff -a21