tests: subsys: logging: timestamp: add custom timestamp tests

Adds tests for the custom timestamp functionality. It also
includes a basic test for the default behaviour.

Signed-off-by: Hein Wessels <heinwessels93@gmail.com>

tests/subsys/logging/log_timestamp/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(log_output)
+
+FILE(GLOB app_sources src/*.c)
+target_sources(app PRIVATE ${app_sources})

tests/subsys/logging/log_timestamp/prj.conf

@@ -0,0 +1,6 @@
+CONFIG_ZTEST=y
+CONFIG_ZTEST_NEW_API=y
+CONFIG_TEST_LOGGING_DEFAULTS=n
+CONFIG_LOG=y
+CONFIG_LOG_OUTPUT=y
+CONFIG_LOG_PRINTK=n

tests/subsys/logging/log_timestamp/src/log_timestamp_test.c

@@ -0,0 +1,86 @@
+/*
+ * Copyright (c) 2023 Nobleo Technology
+ *
+ * SPDX-License-Identifier: Apache-2.0
+ */
+
+/**
+ * @file
+ * @brief Test log timestamp
+ */
+
+#include <zephyr/logging/log.h>
+#include <zephyr/logging/log_output.h>
+#include <zephyr/logging/log_output_custom.h>
+
+#include <zephyr/tc_util.h>
+#include <stdbool.h>
+#include <zephyr/kernel.h>
+#include <zephyr/ztest.h>
+
+#define LOG_MODULE_NAME test
+LOG_MODULE_REGISTER(LOG_MODULE_NAME);
+
+#define SNAME "src"
+#define DNAME "domain"
+#define TEST_STR "test"
+
+static uint8_t mock_buffer[512];
+static uint8_t log_output_buf[4];
+static uint32_t mock_len;
+
+static void reset_mock_buffer(void)
+{
+	mock_len = 0U;
+	memset(mock_buffer, 0, sizeof(mock_buffer));
+}
+
+static int mock_output_func(uint8_t *buf, size_t size, void *ctx)
+{
+	memcpy(&mock_buffer[mock_len], buf, size);
+	mock_len += size;
+
+	return size;
+}
+
+LOG_OUTPUT_DEFINE(log_output, mock_output_func,
+		  log_output_buf, sizeof(log_output_buf));
+
+int custom_timestamp(const struct log_output *output,
+				const log_timestamp_t timestamp,
+				const log_timestamp_printer_t printer)
+{
+	uint8_t buffer[] = "custom-timestamp: ";
+
+	return printer(output, "%s", buffer);
+}
+
+ZTEST(test_timestamp, test_custom_timestamp)
+{
+	if (IS_ENABLED(CONFIG_LOG_OUTPUT_FORMAT_CUSTOM_TIMESTAMP)) {
+		log_custom_timestamp_set(custom_timestamp);
+	}
+	static const char *exp_str = IS_ENABLED(CONFIG_LOG_OUTPUT_FORMAT_CUSTOM_TIMESTAMP) ?
+			"custom-timestamp: " DNAME "/" SNAME ": " TEST_STR "\r\n" :
+			"[00000001] " DNAME "/" SNAME ": " TEST_STR "\r\n";
+
+	char package[256];
+	uint32_t flags = LOG_OUTPUT_FLAG_TIMESTAMP;
+	int err;
+
+	err = cbprintf_package(package, sizeof(package), 0, TEST_STR);
+	zassert_true(err > 0);
+
+	log_output_process(&log_output, 1, DNAME, SNAME, LOG_LEVEL_INF,
+			   package, NULL, 0, flags);
+
+	mock_buffer[mock_len] = '\0';
+	zassert_equal(strcmp(exp_str, mock_buffer), 0);
+}
+
+static void before(void *notused)
+{
+	reset_mock_buffer();
+}
+
+ZTEST_SUITE(test_timestamp, NULL, NULL, before, NULL, NULL);

tests/subsys/logging/log_timestamp/testcase.yaml

@@ -0,0 +1,11 @@
+common:
+  integration_platforms:
+    - native_posix
+
+tests:
+  logging.log_output_default_timestamp:
+    tags: log_output logging timestamp
+  logging.log_output_custom_timestamp:
+    tags: log_output logging timestamp
+    extra_configs:
+      - CONFIG_LOG_OUTPUT_FORMAT_CUSTOM_TIMESTAMP=y