logging: Add LOG_RAW macro

Add macro for logging raw formatted string. It is similar to
LOG_PRINTK macro but contrary to LOG_PRINTK it should not append
carriage return character to any new line character found in the
string. LOG_PRINTK processed by log_output module has that to
mimic printk behavior.

Signed-off-by: Krzysztof Chruscinski <krzysztof.chruscinski@nordicsemi.no>

include/zephyr/logging/log.h

@@ -79,7 +79,17 @@ extern "C" {
  * @param ... A string optionally containing printk valid conversion specifier,
  * followed by as many values as specifiers.
  */
-#define LOG_PRINTK(...) Z_LOG_PRINTK(__VA_ARGS__)
+#define LOG_PRINTK(...) Z_LOG_PRINTK(0, __VA_ARGS__)
+
+/**
+ * @brief Unconditionally print raw log message.
+ *
+ * Provided string is printed as is without appending any characters (e.g., color or newline).
+ *
+ * @param ... A string optionally containing printk valid conversion specifier,
+ * followed by as many values as specifiers.
+ */
+#define LOG_RAW(...) Z_LOG_PRINTK(1, __VA_ARGS__)
 
 /**
  * @brief Writes an ERROR level message associated with the instance to the log.

include/zephyr/logging/log_core.h

@@ -391,7 +391,17 @@ static inline char z_log_minimal_level_to_char(int level)
 extern struct log_source_const_data __log_const_start[];
 extern struct log_source_const_data __log_const_end[];
 
-#define Z_LOG_PRINTK(...) do { \
+/** @brief Create message for logging printk-like string or a raw string.
+ *
+ * Part of printk string processing is appending of carriage return after any
+ * new line character found in the string. If it is not desirable then @p _is_raw
+ * can be set to 1 to indicate raw string. This information is stored in the source
+ * field which is not used for its typical purpose in this case.
+ *
+ * @param _is_raw	Set to 1 to indicate raw string, set to 0 to indicate printk.
+ * @param ...		Format string with arguments.
+ */
+#define Z_LOG_PRINTK(_is_raw, ...) do { \
 	if (IS_ENABLED(CONFIG_LOG_MODE_MINIMAL)) { \
 		z_log_minimal_printk(__VA_ARGS__); \
 		break; \
@@ -401,7 +411,7 @@ extern struct log_source_const_data __log_const_end[];
 		z_log_printf_arg_checker(__VA_ARGS__); \
 	} \
 	Z_LOG_MSG2_CREATE(!IS_ENABLED(CONFIG_USERSPACE), _mode, \
-			  CONFIG_LOG_DOMAIN_ID, NULL, \
+			  CONFIG_LOG_DOMAIN_ID, (uintptr_t)_is_raw, \
 			  LOG_LEVEL_INTERNAL_RAW_STRING, NULL, 0, __VA_ARGS__);\
 } while (0)
 

subsys/logging/log_core.c

@@ -412,6 +412,11 @@ static bool msg_filter_check(struct log_backend const *backend,
 	domain_id = log_msg_get_domain(&msg->log);
 	source_id = source ? log_dynamic_source_id(source) : -1;
 
+	/* Accept all non-logging messages. */
+	if (level == LOG_LEVEL_NONE) {
+		return true;
+	}
+
 	backend_level = log_filter_get(backend, domain_id,
 				       source_id, true);
 

subsys/logging/log_output.c

@@ -491,16 +491,22 @@ void log_output_process(const struct log_output *output,
 {
 	bool raw_string = (level == LOG_LEVEL_INTERNAL_RAW_STRING);
 	uint32_t prefix_offset;
+	cbprintf_cb cb;
 
 	if (!raw_string) {
 		prefix_offset = prefix_print(output, flags, 0, timestamp, domain, source, level);
+		cb = out_func;
 	} else {
 		prefix_offset = 0;
+		/* source set to 1 indicates raw string and contrary to printk
+		 * case it should not append anything to the output (printk is
+		 * appending <CR> to the new line character).
+		 */
+		cb = ((uintptr_t)source == 1) ? out_func : cr_out_func;
 	}
 
 	if (package) {
-		int err = cbpprintf(raw_string ? cr_out_func :  out_func,
+		int err = cbpprintf(cb, (void *)output, (void *)package);
-				    (void *)output, (void *)package);
 
 		(void)err;
 		__ASSERT_NO_MSG(err >= 0);