debug_stream: text_msg: add va_list-based logging helper

Add ds_vamsg(const char *format, va_list ap) to the debug stream
text message API and implementation.

Refactor ds_msg() to forward to ds_vamsg() so formatting and record
emission are handled in one shared path.

This enables callers that already operate on va_list to emit debug
stream text messages without rebuilding variadic arguments, and keeps the
message construction logic centralized.

Signed-off-by: Jyri Sarha <jyri.sarha@linux.intel.com>

Author: Jyri Sarha

src/debug/debug_stream/debug_stream_text_msg.c

@@ -15,18 +15,15 @@
 
 LOG_MODULE_REGISTER(debug_stream_text_msg);
 
-void ds_msg(const char *format, ...)
+void ds_vamsg(const char *format, va_list args)
 {
-	va_list args;
 	struct {
 		struct debug_stream_text_msg msg;
 		char text[128];
 	} __packed buf = { 0 };
 	ssize_t len;
 
-	va_start(args, format);
 	len = vsnprintf(buf.text, sizeof(buf.text), format, args);
-	va_end(args);
 
 	if (len < 0)
 		return;
@@ -38,6 +35,15 @@ void ds_msg(const char *format, ...)
 	debug_stream_slot_send_record(&buf.msg.hdr);
 }
 
+void ds_msg(const char *format, ...)
+{
+	va_list args;
+
+	va_start(args, format);
+	ds_vamsg(format, args);
+	va_end(args);
+}
+
 #if defined(CONFIG_EXCEPTION_DUMP_HOOK)
 /* The debug stream debug window slot is 4k, and when it is split
  * between the cores and the header/other overhead is removed, with 5

src/include/user/debug_stream_text_msg.h

@@ -7,6 +7,7 @@
 #define __SOC_DEBUG_STREAM_TEXT_MSG_H__
 
 #include <user/debug_stream_slot.h>
+#include <stdarg.h>
 
 /*
  * Debug Stream text message.
@@ -21,5 +22,6 @@ struct debug_stream_text_msg {
  * CONFIG_SOF_DEBUG_STREAM_TEXT_MSG to enable this function.
  */
 void ds_msg(const char *format, ...);
+void ds_vamsg(const char *format, va_list ap);
 
 #endif /*  __SOC_DEBUG_STREAM_TEXT_MSG_H__ */