tests: lib: Add ipc_icmsg_buf unit tests

This commit adds unit tests for ipc_icmsg_buf library of ipc_service.

Signed-off-by: Emil Obalski <emil.obalski@nordicsemi.no>

tests/lib/icmsg/CMakeLists.txt

@@ -0,0 +1,8 @@
+# SPDX-License-Identifier: Apache-2.0
+
+cmake_minimum_required(VERSION 3.20.0)
+find_package(Zephyr REQUIRED HINTS $ENV{ZEPHYR_BASE})
+project(icmsg)
+
+FILE(GLOB app_sources src/main.c)
+target_sources(app PRIVATE ${app_sources})

tests/lib/icmsg/prj.conf

@@ -0,0 +1,4 @@
+CONFIG_ZTEST=y
+
+CONFIG_IPC_SERVICE=y
+CONFIG_IPC_SERVICE_ICMSG_BUF=y

tests/lib/icmsg/src/main.c

@@ -0,0 +1,110 @@
+/*
+ * Copyright (c) 2022 Nordic Semiconductor ASA
+ *
+ * SPDX-License-Identifier: Apache-2.0
+ */
+
+#include <ztest.h>
+#include <ipc/ipc_icmsg_buf.h>
+
+/* The buffer size itself would be 199 bytes.
+ * 212 - sizeof(struct icmsg_buf) - 1 = 199.
+ * -1 because internal rd/wr_idx is reserved to mean the buffer is empty.
+ */
+static uint8_t memory_area[212];
+
+static void test_icmsg_buf_ut(void)
+{
+	static uint8_t rbuf[198];
+	static uint8_t message[20] = {'a'};
+	struct icmsg_buf *ib;
+	int rlen;
+	int wlen;
+
+	ib = icmsg_buf_init(memory_area, sizeof(memory_area));
+	zassert_equal_ptr(ib, memory_area, NULL);
+	zassert_equal(ib->len, (sizeof(memory_area) - sizeof(*ib)), NULL);
+	zassert_equal(ib->wr_idx, 0, NULL);
+	zassert_equal(ib->rd_idx, 0, NULL);
+
+	/* Try to write more than buffer can store. */
+	rlen = icmsg_buf_write(ib, rbuf, sizeof(rbuf));
+	zassert_equal(rlen, -ENOMEM, NULL);
+	zassert_equal(ib->wr_idx, 0, NULL);
+	zassert_equal(ib->rd_idx, 0, NULL);
+
+	/* Read empty buffer. */
+	rlen = icmsg_buf_read(ib, rbuf, sizeof(rbuf));
+	zassert_equal(rlen, 0, NULL);
+
+	/* Single write and read. */
+	wlen = icmsg_buf_write(ib, message, sizeof(message));
+	zassert_equal(wlen, sizeof(message), NULL);
+	zassert_equal(ib->wr_idx, (sizeof(message) + sizeof(uint16_t)), NULL);
+	zassert_equal(ib->rd_idx, 0, NULL);
+
+	rlen = icmsg_buf_read(ib, rbuf, sizeof(rbuf));
+	zassert_equal(rlen, sizeof(message), NULL);
+	zassert_equal(ib->wr_idx, (sizeof(message) + sizeof(uint16_t)), NULL);
+	zassert_equal(ib->rd_idx, (sizeof(message) + sizeof(uint16_t)), NULL);
+
+	/* Buffer size is 212 - 12 = 200 Bytes for len, wr_idx, rd_idx.
+	 * When writing message of 20 Bytes, actually 22 Bytes are stored,
+	 * (2 Bytes reserved for message len). Test if after 9 writes, 10th write
+	 * would return -ENOMEM. 200 - (9 * 22) = 2 bytes left.
+	 *
+	 * Reset the buffer first.
+	 */
+	ib = icmsg_buf_init(memory_area, sizeof(memory_area));
+	zassert_equal_ptr(ib, memory_area, NULL);
+	zassert_equal(ib->len, (sizeof(memory_area) - sizeof(*ib)), NULL);
+	zassert_equal(ib->wr_idx, 0, NULL);
+	zassert_equal(ib->rd_idx, 0, NULL);
+
+	for (size_t i = 0; i < 9; i++) {
+		wlen = icmsg_buf_write(ib, message, sizeof(message));
+		zassert_equal(wlen, sizeof(message), NULL);
+	}
+
+	wlen = icmsg_buf_write(ib, message, sizeof(message));
+	zassert_equal(wlen, -ENOMEM, NULL);
+
+	/* Test reading with buf == NULL, should return len of the next message to read. */
+	rlen = icmsg_buf_read(ib, NULL, 0);
+	zassert_equal(rlen, sizeof(message), NULL);
+
+	/* Read with len == 0 and correct buf pointer. */
+	rlen = icmsg_buf_read(ib, rbuf, 0);
+	zassert_equal(rlen, -ENOMEM, NULL);
+
+	/* Read whole data from the buffer. */
+	for (size_t i = 0; i < 9; i++) {
+		zassert_equal(ib->rd_idx, i * (sizeof(message) + sizeof(uint16_t)), NULL);
+		wlen = icmsg_buf_read(ib, rbuf, sizeof(rbuf));
+		zassert_equal(wlen, sizeof(message), NULL);
+	}
+
+	zassert_equal(ib->wr_idx, 9 * (sizeof(message) + sizeof(uint16_t)), NULL);
+	zassert_equal(ib->rd_idx, 9 * (sizeof(message) + sizeof(uint16_t)), NULL);
+
+	/* Write message that would be wrapped around. */
+	wlen = icmsg_buf_write(ib, message, sizeof(message));
+	zassert_equal(wlen, sizeof(message), NULL);
+	/* Have to store 22 bytes in total.
+	 * 2 Bytes left in tail of the buffer 20 bytes go in front.
+	 */
+	zassert_equal(ib->wr_idx, 20, NULL);
+
+	/* Read wrapped message. */
+	rlen = icmsg_buf_read(ib, rbuf, sizeof(rbuf));
+	zassert_equal(rlen, sizeof(message), NULL);
+	zassert_equal(message[0], 'a', NULL);
+}
+
+void test_main(void)
+{
+	ztest_test_suite(icmsg_buf,
+			ztest_unit_test(test_icmsg_buf_ut)
+			);
+	ztest_run_test_suite(icmsg_buf);
+}

tests/lib/icmsg/testcase.yaml

@@ -0,0 +1,5 @@
+tests:
+  libraries.icmsg:
+    integration_platforms:
+      - nrf5340dk_nrf5340_cpuapp
+    platform_exclude: qemu_xtensa qemu_malta