Add a test for fgets

tests/Makefile

@@ -2,7 +2,9 @@ CC=../x86_64-linux-musl-native/bin/gcc
 GCOV=../x86_64-linux-musl-native/bin/gcov
 CFLAGS=-I../include/ -D_FORTIFY_SOURCE=3 -static -O2
 
-TARGETS=test_memcpy_static_write     \
+TARGETS= \
+	test_fgets                   \
+	test_memcpy_static_write     \
 	test_memcpy_dynamic_write    \
 	test_memcpy_static_read      \
 	test_memcpy_dynamic_read     \

tests/test_fgets.c

@@ -0,0 +1,15 @@
+#include "common.h"
+
+#define _GNU_SOURCE
+#include <poll.h>
+
+int main(int argc, char** argv) {
+  char buffer[12] = {0};
+
+  CHK_FAIL_START
+  fgets(buffer, 14, NULL);
+  CHK_FAIL_END
+
+  puts(buffer);
+  return ret;
+}