test: ipc: unix: Add test for IPCUnixSocket

Test that the IPC supports sending data and file descriptors over the
IPC medium. To be able to execute the test two parts are needed, one
to drive the test and act as the libcamera (master) and a one to act as
the IPA (slave).

The master drives the testing posting requests to the slave to process
and sometimes respond to. A few different tests are performed.

- Master sends an array to the slave which responds with a reversed copy
  of the array. The master verifies that a reversed array is returned.

- Master tries to send an empty message making sure that the send call
  fails.

- Master sends a list of file descriptors and ask the slave to calculate
  and respond with the sum of the size of the files. The master verifies
  that the calculated size is correct.

- Master sends a pre-computed size and a list of file descriptors and
  asks the slave to verify that the pre-computed size matches the sum of
  the size of the file descriptors.

- Master sends two file descriptors and asks the slave to join the file
  contents in a new file and respond with its file descriptor. The
  master then verifies that the content of the returned file descriptor
  matches the order of the original two files.

Signed-off-by: Niklas Söderlund <niklas.soderlund@ragnatech.se>
Reviewed-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
Signed-off-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>

3 files changed, 515 insertions, 0 deletions

diff --git a/test/ipc/meson.build b/test/ipc/meson.build
new file mode 100644
index 00000000..ca8375f3
--- /dev/null
+++ b/test/ipc/meson.build
@@ -0,0 +1,12 @@
+ipc_tests = [
+    [ 'unixsocket',  'unixsocket.cpp' ],
+]
+
+foreach t : ipc_tests
+    exe = executable(t[0], t[1],
+                     dependencies : libcamera_dep,
+                     link_with : test_libraries,
+                     include_directories : test_includes_internal)
+
+    test(t[0], exe, suite : 'ipc', is_parallel : false)
+endforeach
diff --git a/test/ipc/unixsocket.cpp b/test/ipc/unixsocket.cpp
new file mode 100644
index 00000000..eeef6484
--- /dev/null
+++ b/test/ipc/unixsocket.cpp
@@ -0,0 +1,502 @@
+/* SPDX-License-Identifier: GPL-2.0-or-later */
+/*
+ * Copyright (C) 2019, Google Inc.
+ *
+ * unixsocket.cpp - Unix socket IPC test
+ */
+
+#include <algorithm>
+#include <fcntl.h>
+#include <iostream>
+#include <stdlib.h>
+#include <string.h>
+#include <sys/stat.h>
+#include <sys/types.h>
+#include <sys/wait.h>
+#include <unistd.h>
+
+#include <libcamera/camera_manager.h>
+#include <libcamera/event_dispatcher.h>
+#include <libcamera/timer.h>
+
+#include "ipc_unixsocket.h"
+#include "test.h"
+#include "utils.h"
+
+#define CMD_CLOSE	0
+#define CMD_REVERSE	1
+#define CMD_LEN_CALC	2
+#define CMD_LEN_CMP	3
+#define CMD_JOIN	4
+
+using namespace std;
+using namespace libcamera;
+
+int calculateLength(int fd)
+{
+	lseek(fd, 0, 0);
+	int size = lseek(fd, 0, SEEK_END);
+	lseek(fd, 0, 0);
+
+	return size;
+}
+
+class UnixSocketTestSlave
+{
+public:
+	UnixSocketTestSlave()
+		: exitCode_(EXIT_FAILURE), exit_(false)
+	{
+		dispatcher_ = CameraManager::instance()->eventDispatcher();
+		ipc_.readyRead.connect(this, &UnixSocketTestSlave::readyRead);
+	}
+
+	int run(int fd)
+	{
+		if (ipc_.bind(fd)) {
+			cerr << "Failed to connect to IPC channel" << endl;
+			return EXIT_FAILURE;
+		}
+
+		while (!exit_)
+			dispatcher_->processEvents();
+
+		ipc_.close();
+
+		return exitCode_;
+	}
+
+private:
+	void readyRead(IPCUnixSocket *ipc)
+	{
+		IPCUnixSocket::Payload message, response;
+		int ret;
+
+		ret = ipc->receive(&message);
+		if (ret) {
+			cerr << "Receive message failed: " << ret << endl;
+			return;
+		}
+
+		const uint8_t cmd = message.data[0];
+
+		switch (cmd) {
+		case CMD_CLOSE:
+			stop(0);
+			break;
+
+		case CMD_REVERSE: {
+			response.data = message.data;
+			std::reverse(response.data.begin() + 1, response.data.end());
+
+			ret = ipc_.send(response);
+			if (ret < 0) {
+				cerr << "Reverse failed" << endl;
+				stop(ret);
+			}
+			break;
+		}
+
+		case CMD_LEN_CALC: {
+			int size = 0;
+			for (int fd : message.fds)
+				size += calculateLength(fd);
+
+			response.data.resize(1 + sizeof(size));
+			response.data[0] = cmd;
+			memcpy(response.data.data() + 1, &size, sizeof(size));
+
+			ret = ipc_.send(response);
+			if (ret < 0) {
+				cerr << "Calc failed" << endl;
+				stop(ret);
+			}
+			break;
+		}
+
+		case CMD_LEN_CMP: {
+			int size = 0;
+			for (int fd : message.fds)
+				size += calculateLength(fd);
+
+			int cmp;
+			memcpy(&cmp, message.data.data() + 1, sizeof(cmp));
+
+			if (cmp != size) {
+				cerr << "Compare failed" << endl;
+				stop(-ERANGE);
+			}
+			break;
+		}
+
+		case CMD_JOIN: {
+			int outfd = open("/tmp", O_TMPFILE | O_RDWR,
+					 S_IRUSR | S_IWUSR);
+			if (outfd < 0) {
+				cerr << "Create out file failed" << endl;
+				stop(outfd);
+				return;
+			}
+
+			for (int fd : message.fds) {
+				while (true) {
+					char buf[32];
+					ssize_t num = read(fd, &buf, sizeof(buf));
+
+					if (num < 0) {
+						cerr << "Read failed" << endl;
+						stop(-EIO);
+						return;
+					} else if (!num)
+						break;
+
+					if (write(outfd, buf, num) < 0) {
+						cerr << "Write failed" << endl;
+						stop(-EIO);
+						return;
+					}
+				}
+
+				close(fd);
+			}
+
+			lseek(outfd, 0, 0);
+			response.data.push_back(CMD_JOIN);
+			response.fds.push_back(outfd);
+
+			ret = ipc_.send(response);
+			if (ret < 0) {
+				cerr << "Join failed" << endl;
+				stop(ret);
+			}
+
+			close(outfd);
+
+			break;
+		}
+
+		default:
+			cerr << "Unknown command " << cmd << endl;
+			stop(-EINVAL);
+			break;
+		}
+	}
+
+	void stop(int code)
+	{
+		exitCode_ = code;
+		exit_ = true;
+	}
+
+	IPCUnixSocket ipc_;
+	EventDispatcher *dispatcher_;
+	int exitCode_;
+	bool exit_;
+};
+
+class UnixSocketTest : public Test
+{
+protected:
+	int slaveStart(int fd)
+	{
+		pid_ = fork();
+
+		if (pid_ == -1)
+			return TestFail;
+
+		if (!pid_) {
+			std::string arg = std::to_string(fd);
+			execl("/proc/self/exe", "/proc/self/exe",
+			      arg.c_str(), nullptr);
+
+			/* Only get here if exec fails. */
+			exit(TestFail);
+		}
+
+		return TestPass;
+	}
+
+	int slaveStop()
+	{
+		int status;
+
+		if (pid_ < 0)
+			return TestFail;
+
+		if (waitpid(pid_, &status, 0) < 0)
+			return TestFail;
+
+		if (!WIFEXITED(status) || WEXITSTATUS(status))
+			return TestFail;
+
+		return TestPass;
+	}
+
+	int testReverse()
+	{
+		IPCUnixSocket::Payload message, response;
+		int ret;
+
+		message.data = { CMD_REVERSE, 1, 2, 3, 4, 5 };
+
+		ret = call(message, &response);
+		if (ret)
+			return ret;
+
+		std::reverse(response.data.begin() + 1, response.data.end());
+		if (message.data != response.data)
+			return TestFail;
+
+		return 0;
+	}
+
+	int testEmptyFail()
+	{
+		IPCUnixSocket::Payload message;
+
+		return ipc_.send(message) != -EINVAL;
+	}
+
+	int testCalc()
+	{
+		IPCUnixSocket::Payload message, response;
+		int sizeOut, sizeIn, ret;
+
+		sizeOut = prepareFDs(&message, 2);
+		if (sizeOut < 0)
+			return sizeOut;
+
+		message.data.push_back(CMD_LEN_CALC);
+
+		ret = call(message, &response);
+		if (ret)
+			return ret;
+
+		memcpy(&sizeIn, response.data.data() + 1, sizeof(sizeIn));
+		if (sizeOut != sizeIn)
+			return TestFail;
+
+		return 0;
+	}
+
+	int testCmp()
+	{
+		IPCUnixSocket::Payload message;
+		int size;
+
+		size = prepareFDs(&message, 7);
+		if (size < 0)
+			return size;
+
+		message.data.resize(1 + sizeof(size));
+		message.data[0] = CMD_LEN_CMP;
+		memcpy(message.data.data() + 1, &size, sizeof(size));
+
+		if (ipc_.send(message))
+			return TestFail;
+
+		return 0;
+	}
+
+	int testFdOrder()
+	{
+		IPCUnixSocket::Payload message, response;
+		int ret;
+
+		static const char *strings[2] = {
+			"Foo",
+			"Bar",
+		};
+		int fds[2];
+
+		for (unsigned int i = 0; i < ARRAY_SIZE(strings); i++) {
+			unsigned int len = strlen(strings[i]);
+
+			fds[i] = open("/tmp", O_TMPFILE | O_RDWR,
+				      S_IRUSR | S_IWUSR);
+			if (fds[i] < 0)
+				return TestFail;
+
+			ret = write(fds[i], strings[i], len);
+			if (ret < 0)
+				return TestFail;
+
+			lseek(fds[i], 0, 0);
+			message.fds.push_back(fds[i]);
+		}
+
+		message.data.push_back(CMD_JOIN);
+
+		ret = call(message, &response);
+		if (ret)
+			return ret;
+
+		for (unsigned int i = 0; i < ARRAY_SIZE(strings); i++) {
+			unsigned int len = strlen(strings[i]);
+			char buf[len];
+
+			close(fds[i]);
+
+			if (read(response.fds[0], &buf, len) <= 0)
+				return TestFail;
+
+			if (memcmp(buf, strings[i], len))
+				return TestFail;
+		}
+
+		close(response.fds[0]);
+
+		return 0;
+	}
+
+	int init()
+	{
+		callResponse_ = nullptr;
+		return 0;
+	}
+
+	int run()
+	{
+		int slavefd = ipc_.create();
+		if (slavefd < 0)
+			return TestFail;
+
+		if (slaveStart(slavefd)) {
+			cerr << "Failed to start slave" << endl;
+			return TestFail;
+		}
+
+		ipc_.readyRead.connect(this, &UnixSocketTest::readyRead);
+
+		/* Test reversing a string, this test sending only data. */
+		if (testReverse()) {
+			cerr << "Reveres array test failed" << endl;
+			return TestFail;
+		}
+
+		/* Test that an empty message fails. */
+		if (testEmptyFail()) {
+			cerr << "Empty message test failed" << endl;
+			return TestFail;
+		}
+
+		/* Test offloading a calculation, this test sending only FDs. */
+		if (testCalc()) {
+			cerr << "Calc test failed" << endl;
+			return TestFail;
+		}
+
+		/* Test fire and forget, this tests sending data and FDs. */
+		if (testCmp()) {
+			cerr << "Cmp test failed" << endl;
+			return TestFail;
+		}
+
+		/* Test order of file descriptors. */
+		if (testFdOrder()) {
+			cerr << "fd order test failed" << endl;
+			return TestFail;
+		}
+
+		/* Close slave connection. */
+		IPCUnixSocket::Payload close;
+		close.data.push_back(CMD_CLOSE);
+		if (ipc_.send(close)) {
+			cerr << "Closing IPC channel failed" << endl;
+			return TestFail;
+		}
+
+		ipc_.close();
+		if (slaveStop()) {
+			cerr << "Failed to stop slave" << endl;
+			return TestFail;
+		}
+
+		return TestPass;
+	}
+
+private:
+	int call(const IPCUnixSocket::Payload &message, IPCUnixSocket::Payload *response)
+	{
+		Timer timeout;
+		int ret;
+
+		callDone_ = false;
+		callResponse_ = response;
+
+		ret = ipc_.send(message);
+		if (ret)
+			return ret;
+
+		timeout.start(200);
+		while (!callDone_) {
+			if (!timeout.isRunning()) {
+				cerr << "Call timeout!" << endl;
+				callResponse_ = nullptr;
+				return -ETIMEDOUT;
+			}
+
+			CameraManager::instance()->eventDispatcher()->processEvents();
+		}
+
+		callResponse_ = nullptr;
+
+		return 0;
+	}
+
+	void readyRead(IPCUnixSocket *ipc)
+	{
+		if (!callResponse_) {
+			cerr << "Read ready without expecting data, fail." << endl;
+			return;
+		}
+
+		if (ipc->receive(callResponse_)) {
+			cerr << "Receive message failed" << endl;
+			return;
+		}
+
+		callDone_ = true;
+	}
+
+	int prepareFDs(IPCUnixSocket::Payload *message, unsigned int num)
+	{
+		int fd = open("/proc/self/exe", O_RDONLY);
+		if (fd < 0)
+			return fd;
+
+		int size = 0;
+		for (unsigned int i = 0; i < num; i++) {
+			int clone = dup(fd);
+			if (clone < 0)
+				return clone;
+
+			size += calculateLength(clone);
+			message->fds.push_back(clone);
+		}
+
+		close(fd);
+
+		return size;
+	}
+
+	pid_t pid_;
+	IPCUnixSocket ipc_;
+	bool callDone_;
+	IPCUnixSocket::Payload *callResponse_;
+};
+
+/*
+ * Can't use TEST_REGISTER() as single binary needs to act as both proxy
+ * master and slave.
+ */
+int main(int argc, char **argv)
+{
+	if (argc == 2) {
+		int ipcfd = std::stoi(argv[1]);
+		UnixSocketTestSlave slave;
+		return slave.run(ipcfd);
+	}
+
+	return UnixSocketTest().execute();
+}
diff --git a/test/meson.build b/test/meson.build
index c36ac247..3666f6b2 100644
--- a/test/meson.build
+++ b/test/meson.build
@@ -2,6 +2,7 @@ subdir('libtest')
 
 subdir('camera')
 subdir('ipa')
+subdir('ipc')
 subdir('media_device')
 subdir('pipeline')
 subdir('stream')