Add syslog output support to bootloader

Broadcast console output as syslog debug messages, stripped of trailing newlines.
Disabled by default.

Patch from #6168.

Change-Id: I1754381477dcde00bdcfa4482017daf5eb682cd3
Reviewed-on: https://review.haiku-os.org/c/912
Reviewed-by: Stephan Aßmus <[email protected]>

src/system/boot/loader/stdio.cpp

@@ -6,6 +6,8 @@
 
 #include <boot/vfs.h>
 #include <boot/stdio.h>
+#include <boot/net/NetStack.h>
+#include <boot/net/UDP.h>
 
 #include <errno.h>
 #include <stdarg.h>
@@ -20,6 +22,9 @@
 //extern FILE *stdin;
 
 
+//#define ENABLE_SYSLOG
+
+
 #undef errno
 int errno;
 
@@ -31,6 +36,51 @@ _errnop(void)
 }
 
 
+#ifdef ENABLE_SYSLOG
+
+static UDPSocket *sSyslogSocket = NULL;
+
+static void
+sendToSyslog(const char *message, int length)
+{
+	// Lazy-initialize the socket
+	if (sSyslogSocket == NULL) {
+		// Check if the network stack has been initialized yet
+		if (NetStack::Default() != NULL) {
+			sSyslogSocket = new(std::nothrow) UDPSocket;
+			sSyslogSocket->Bind(INADDR_ANY, 60514);
+		}
+	}
+
+	if (sSyslogSocket == NULL)
+		return;
+
+	// Strip trailing newlines
+	while (length > 0) {
+		if (message[length - 1] != '\n'
+			&& message[length - 1] != '\r') {
+			break;
+		}
+		length--;
+	}
+	if (length <= 0)
+		return;
+
+	char buffer[1500];
+		// same comment as in vfprintf applies...
+	const int facility = 0; // kernel
+	int severity = 7; // debug
+	int offset = snprintf(buffer, sizeof(buffer),
+		"<%d>1 - - Haiku - - - \xEF\xBB\xBF",
+		facility * 8 + severity);
+	length = std::min(length, (int)sizeof(buffer) - offset);
+	memcpy(buffer + offset, message, length);
+	sSyslogSocket->Send(INADDR_BROADCAST, 514, buffer, offset + length);
+}
+
+#endif
+
+
 int
 vfprintf(FILE *file, const char *format, va_list list)
 {
@@ -40,8 +90,12 @@ vfprintf(FILE *file, const char *format, va_list list)
 
 	int length = vsnprintf(buffer, sizeof(buffer), format, list);
 	length = std::min(length, (int)sizeof(buffer) - 1);
-	if (length > 0)
+	if (length > 0) {
 		node->Write(buffer, length);
+#ifdef ENABLE_SYSLOG
+		sendToSyslog(buffer, length);
+#endif
+	}
 
 	return length;
 }
@@ -92,6 +146,10 @@ fputc(int c, FILE *file)
 	// we only support direct console output right now...
 	status = ((ConsoleNode *)file)->Write(&character, 1);
 
+#ifdef ENABLE_SYSLOG
+	sendToSyslog(&character, 1);
+#endif
+
 	if (status > 0)
 		return character;
 
@@ -108,6 +166,10 @@ fputs(const char *string, FILE *file)
 	status_t status = ((ConsoleNode *)file)->Write(string, strlen(string));
 	fputc('\n', file);
 
+#ifdef ENABLE_SYSLOG
+	sendToSyslog(string, strlen(string));
+#endif
+
 	return status;
 }