tests: Add initial osmo_io tests

Change-Id: Ia67629e53f4d2e5784177250d58e268fdfcaa0c2
diff --git a/tests/osmo_io/osmo_io_test.c b/tests/osmo_io/osmo_io_test.c
new file mode 100644
index 0000000..1991926
--- /dev/null
+++ b/tests/osmo_io/osmo_io_test.c
@@ -0,0 +1,179 @@
+/*
+ * (C) 2023 by sysmocom s.f.m.c
+ * Author: Daniel Willmann <daniel@sysmocom.de>
+ *
+ * All Rights Reserved
+ *
+ * SPDX-License-Identifier: GPL-2.0+
+ *
+ * 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; either version 2 of the License, or
+ * (at your option) any later version.
+ *
+ * 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.
+ *
+ */
+
+#include <stdio.h>
+#include <stdint.h>
+#include <stdlib.h>
+#include <unistd.h>
+#include <string.h>
+#include <sys/socket.h>
+#include <errno.h>
+
+#include <osmocom/core/application.h>
+#include <osmocom/core/bits.h>
+#include <osmocom/core/logging.h>
+#include <osmocom/core/msgb.h>
+#include <osmocom/core/osmo_io.h>
+#include <osmocom/core/select.h>
+#include <osmocom/core/utils.h>
+
+#include "config.h"
+
+#define TEST_START() printf("Running %s\n", __func__)
+
+static void *ctx = NULL;
+
+static void read_cb(struct osmo_io_fd *iofd, int rc, struct msgb *msg)
+{
+	printf("%s: read() msg with len=%d\n", osmo_iofd_get_name(iofd), rc);
+	if (msg)
+		printf("%s\n", osmo_hexdump(msgb_data(msg), msgb_length(msg)));
+
+	talloc_free(msg);
+}
+
+static void write_cb(struct osmo_io_fd *iofd, int rc, const struct msgb *msg)
+{
+	printf("%s: write() returned rc=%d\n", osmo_iofd_get_name(iofd), rc);
+}
+
+struct osmo_io_ops ioops_conn_read_write = {
+	.read_cb = read_cb,
+	.write_cb = write_cb,
+};
+
+uint8_t TESTDATA[] = {
+	1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16
+};
+
+static void test_connected(void)
+{
+	int fds[2] = {0, 0}, rc;
+	struct osmo_io_fd *iofd1, *iofd2;
+	struct msgb *msg;
+	uint8_t *buf;
+
+	TEST_START();
+
+	rc = socketpair(AF_UNIX, SOCK_STREAM, 0, fds);
+	OSMO_ASSERT(rc == 0);
+
+	iofd1 = osmo_iofd_setup(ctx, fds[0], "ep1", OSMO_IO_FD_MODE_READ_WRITE, &ioops_conn_read_write, NULL);
+	osmo_iofd_register(iofd1, fds[0]);
+	iofd2 = osmo_iofd_setup(ctx, fds[1], "ep2", OSMO_IO_FD_MODE_READ_WRITE, &ioops_conn_read_write, NULL);
+	osmo_iofd_register(iofd2, fds[1]);
+
+	msg = msgb_alloc(1024, "Test data");
+	buf = msgb_put(msg, sizeof(TESTDATA));
+	memcpy(buf, TESTDATA, sizeof(TESTDATA));
+
+	osmo_iofd_write_msgb(iofd1, msg);
+	osmo_iofd_write_enable(iofd1);
+	osmo_iofd_write_enable(iofd2);
+	osmo_iofd_read_enable(iofd1);
+	osmo_iofd_read_enable(iofd2);
+
+
+	/* Allow enough cycles to handle the messages */
+	for (int i = 0; i < 128; i++)
+		osmo_select_main(1);
+
+	osmo_iofd_free(iofd1);
+	osmo_iofd_free(iofd2);
+}
+
+static void recvfrom_cb(struct osmo_io_fd *iofd, int rc, struct msgb *msg,
+			const struct osmo_sockaddr *saddr)
+{
+	printf("%s: recvfrom() msg with len=%d\n", osmo_iofd_get_name(iofd), rc);
+	if (msg)
+		printf("%s\n", osmo_hexdump(msgb_data(msg), msgb_length(msg)));
+
+	talloc_free(msg);
+}
+
+static void sendto_cb(struct osmo_io_fd *iofd, int rc, const struct msgb *msg,
+		      const struct osmo_sockaddr *daddr)
+{
+	printf("%s: sendto() returned rc=%d\n", osmo_iofd_get_name(iofd), rc);
+}
+
+struct osmo_io_ops ioops_conn_recvfrom_sendto = {
+	.sendto_cb = sendto_cb,
+	.recvfrom_cb = recvfrom_cb,
+};
+
+static void test_unconnected(void)
+{
+	int fds[2] = {0, 0}, rc;
+	struct osmo_io_fd *iofd1, *iofd2;
+	struct msgb *msg;
+	uint8_t *buf;
+
+	TEST_START();
+
+	rc = socketpair(AF_UNIX, SOCK_DGRAM, 0, fds);
+	OSMO_ASSERT(rc == 0);
+
+	iofd1 = osmo_iofd_setup(ctx, fds[0], "ep1", OSMO_IO_FD_MODE_RECVFROM_SENDTO, &ioops_conn_recvfrom_sendto, NULL);
+	osmo_iofd_register(iofd1, fds[0]);
+	iofd2 = osmo_iofd_setup(ctx, fds[1], "ep2", OSMO_IO_FD_MODE_RECVFROM_SENDTO, &ioops_conn_recvfrom_sendto, NULL);
+	osmo_iofd_register(iofd2, fds[1]);
+
+	msg = msgb_alloc(1024, "Test data");
+	buf = msgb_put(msg, sizeof(TESTDATA));
+	memcpy(buf, TESTDATA, sizeof(TESTDATA));
+
+	osmo_iofd_sendto_msgb(iofd1, msg, 0, NULL);
+	osmo_iofd_write_enable(iofd1);
+	osmo_iofd_write_enable(iofd2);
+	osmo_iofd_read_enable(iofd1);
+	osmo_iofd_read_enable(iofd2);
+
+
+	/* Allow enough cycles to handle the messages */
+	for (int i = 0; i < 128; i++)
+		osmo_select_main(1);
+
+	osmo_iofd_free(iofd1);
+	osmo_iofd_free(iofd2);
+}
+static const struct log_info_cat default_categories[] = {
+};
+
+static struct log_info info = {
+	.cat = default_categories,
+	.num_cat = ARRAY_SIZE(default_categories),
+};
+
+int main(int argc, char *argv[])
+{
+	ctx = talloc_named_const(NULL, 0, "osmo_io_test");
+	osmo_init_logging2(ctx, &info);
+	log_set_use_color(osmo_stderr_target, 0);
+	log_set_print_filename2(osmo_stderr_target, LOG_FILENAME_NONE);
+	log_set_print_category(osmo_stderr_target, 0);
+	log_set_print_category_hex(osmo_stderr_target, 0);
+
+	test_connected();
+	test_unconnected();
+
+	return EXIT_SUCCESS;
+}