LibC: Implement vsyslog

otherwise it doesn't seem to find libiconv due to __divdc3

ports/libxml2/build.sh

@@ -10,6 +10,7 @@ CONFIGURE_OPTIONS=(
 )
 
 configure() {
+	CFLAGS='-shared-libgcc' \
 	meson setup \
 		--reconfigure \
 		--cross-file "$MESON_CROSS_FILE" \

userspace/libraries/LibC/include/syslog.h

@@ -5,6 +5,8 @@
 
 #include <sys/cdefs.h>
 
+#include <stdarg.h>
+
 __BEGIN_DECLS
 
 #define LOG_PID		0x01
@@ -47,6 +49,7 @@ void	closelog(void);
 void	openlog(const char* ident, int logopt, int facility);
 int		setlogmask(int maskpri);
 void	syslog(int priority, const char* message, ...);
+void	vsyslog(int priority, const char* format, va_list ap);
 
 __END_DECLS
 

userspace/libraries/LibC/syslog.cpp

@@ -1,4 +1,3 @@
-#include <stdarg.h>
 #include <stdio.h>
 #include <string.h>
 #include <syslog.h>
@@ -17,24 +16,31 @@ void openlog(const char* ident, int option, int facility)
 	s_ident = ident;
 }
 
-void syslog(int priority, const char* format, ...)
-{
-	(void)priority;
-	if (s_ident)
-		fprintf(s_log_file, "%s: ", s_ident);
-	va_list args;
-	va_start(args, format);
-	vfprintf(s_log_file, format, args);
-	va_end(args);
-
-	const size_t format_len = strlen(format);
-	if (format_len && format[format_len - 1] != '\n')
-		fputc('\n', s_log_file);
-}
-
 void closelog()
 {
 	fclose(s_log_file);
 	s_log_file = nullptr;
 	s_ident = nullptr;
 }
+
+void syslog(int priority, const char* format, ...)
+{
+	va_list args;
+	va_start(args, format);
+	vsyslog(priority, format, args);
+	va_end(args);
+}
+
+void vsyslog(int priority, const char* format, va_list ap)
+{
+	(void)priority;
+
+	if (s_ident)
+		fprintf(s_log_file, "%s: ", s_ident);
+
+	vfprintf(s_log_file, format, ap);
+
+	const size_t format_len = strlen(format);
+	if (format_len && format[format_len - 1] != '\n')
+		fputc('\n', s_log_file);
+}