Add test case for file descriptors

Author: mkozlowski

Makefile

@@ -188,7 +188,7 @@ $(B)/libencrypt.so: libencrypt.c
 
 
 tests: $(B)/memcr
-	$(MAKE) -C tests CC=$(CC) MEMCR=../$< COMPRESS_LZ4=$(COMPRESS_LZ4) CHECKSUM_MD5=$(CHECKSUM_MD5) ENCRYPT=$(ENCRYPT)
+	$(MAKE) -C tests CC=$(CC) MEMCR=../$< COMPRESS_LZ4=$(COMPRESS_LZ4) COMPRESS_ZSTD=$(COMPRESS_ZSTD) CHECKSUM_MD5=$(CHECKSUM_MD5) ENCRYPT=$(ENCRYPT)
 
 ifeq ($(ENCRYPT), 1)
 tests: $(B)/libencrypt.so

tests/run.sh

@@ -31,6 +31,7 @@ TIME_START=$(date +%s%N)
 . ./run_ok_test.sh
 . ./run_corrupt_test.sh
 . ./run_signal_test.sh
+. ./run_fd_test.sh
 
 TIME_END=$(date +%s%N)
 TIME_ELAPSED_MS=$(((TIME_END - TIME_START) / 1000000))

tests/run_fd_test.sh

@@ -0,0 +1,75 @@
+#!/bin/sh
+
+if [ "$0" = "$_" ]; then
+	echo "this script should not be called directly"
+	exit 1;
+fi
+
+NAME=./run_fd_test.sh
+
+TEST_CNT=0
+TEST_PIPE=./test-pipe
+
+do_memcr_test()
+{
+	if [ -z "$1" ]; then
+		MEMCR_ENV=""
+	else
+		MEMCR_ENV="$1 "
+	fi
+
+	MEMCR_CMD="$DO$MEMCR_ENV$MEMCR -d /tmp $2"
+	TEST=$3
+
+	TEST_CNT=$((TEST_CNT + 1))
+	echo "${WHITE}[test $TEST_CNT] $MEMCR_CMD -p .. for $TEST${NOFMT}"
+
+	mkfifo $TEST_PIPE
+
+	# start the test
+	./"$TEST" $TEST_PIPE &
+	TPID=$!
+
+	# wait for test to be ready
+	cat $TEST_PIPE
+	rm $TEST_PIPE
+
+	# memcr
+	$MEMCR_CMD -p $TPID
+	RET=$?
+	if [ $RET -ne 0 ]; then
+		echo "${RED}[test $TEST_CNT] failed, memcr exit code is $RET${NOFMT}"
+		kill $TPID
+		return 1
+	fi
+
+	# stop the test
+	kill -USR1 $TPID
+	wait $TPID
+	RET=$?
+	if [ $RET -ne 0 ]; then
+		echo "${RED}[test $TEST_CNT] failed, ${TEST} exit code is $RET${NOFMT}"
+		return 1
+	fi
+
+	echo "${GREEN}[test $TEST_CNT] passed${NOFMT}"
+	return 0
+}
+
+# remove stale test pipe (if any)
+rm -f $TEST_PIPE
+
+TESTS="test-fd"
+
+echo "${BOLD}[+] $NAME start${NOFMT}"
+
+# basic tests
+for OPT in "" "--proc-mem" "--rss-file" "--proc-mem --rss-file"; do
+	for TEST in $TESTS; do
+		do_memcr_test "" "-n $OPT" "$TEST" || exit 1
+	done
+done
+
+echo "${BOLD}[+] $NAME $TEST_CNT tests passed${NOFMT}"
+
+TESTS_DONE=$((TESTS_DONE + TEST_CNT))

tests/test-fd.c

@@ -0,0 +1,112 @@
+/*
+ * Copyright (C) 2025 Mariusz Kozłowski
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public License
+ * as published by the Free Software Foundation, version 2
+ * of the license.
+ *
+ * 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 library; if not, write to the Free Software Foundation,
+ * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301, USA.
+ */
+
+#include <stdio.h>
+#include <stdlib.h>
+#include <sys/types.h>
+#include <sys/stat.h>
+#include <fcntl.h>
+#include <unistd.h>
+#include <string.h>
+#include <signal.h>
+#include <assert.h>
+
+#define PFX "[test-fd] "
+
+#define FD_NUM 1000
+
+static volatile sig_atomic_t signalled;
+
+static void sighandler(int num)
+{
+	signalled = num;
+}
+
+static void notify_ready(const char *pipe)
+{
+	int ret;
+	int fd;
+	char msg[64];
+
+	fd = open(pipe, O_WRONLY);
+	assert(fd >= 0);
+
+	snprintf(msg, sizeof(msg), PFX "pid %d ready\n", getpid());
+	ret = write(fd, msg, strlen(msg));
+	assert(ret == strlen(msg));
+
+	close(fd);
+}
+
+int main(int argc, char *argv[])
+{
+	int ret;
+	int flags[FD_NUM];
+
+	if (argc < 2)
+		return 1;
+
+	signal(SIGUSR1, sighandler);
+
+	printf(PFX "pid %d\n", getpid());
+
+	for (int i = 0; i < FD_NUM - 3; i++) {
+		ret = open("/dev/null", O_RDWR);
+		if (ret == -1) {
+			perror(PFX "open");
+			return 1;
+		}
+	}
+
+	for (int fd = 0; fd < FD_NUM; fd++) {
+		ret = fcntl(fd, F_GETFD);
+		if (ret == -1) {
+			perror(PFX "fcntl");
+			return 1;
+		}
+
+		flags[fd] = ret;
+	}
+
+	printf(PFX "waiting for SIGUSR1\n");
+
+	notify_ready(argv[1]);
+
+	while (!signalled)
+		usleep(10 * 1000);
+
+	printf(PFX "signalled (%s)\n", strsignal(signalled));
+
+	/* test that the fds are still open and have the same flags */
+
+	for (int fd = 0; fd < FD_NUM; fd++) {
+		ret = fcntl(fd, F_GETFD);
+
+		if (ret != flags[fd]) {
+			printf(PFX "not ok, %d != %d for fd %d\n", ret, flags[fd], fd);
+			return 1;
+		}
+	}
+
+	for (int fd = 3; fd < FD_NUM; fd++)
+		close(fd);
+
+	printf(PFX "ok\n");
+
+	return 0;
+}

tests/test-malloc.c

@@ -1,3 +1,21 @@
+/*
+ * Copyright (C) 2024-2025 Mariusz Kozłowski
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public License
+ * as published by the Free Software Foundation, version 2
+ * of the license.
+ *
+ * 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 library; if not, write to the Free Software Foundation,
+ * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301, USA.
+ */
+
 #include <stdio.h>
 #include <stdlib.h>
 #include <sys/types.h>
@@ -79,4 +97,4 @@ int main(int argc, char *argv[])
 
 	free(memb);
 	return 0;
-}
+}