Fix printing of signed numbers

If any operand of the '?' operator is of an unsigned type, the result
is unsigned by default. Thanks to Julian Stecklina for finding
this out.

Fixes #189.

base/run/printf.run

@@ -0,0 +1,32 @@
+build "core init test/printf"
+
+create_boot_directory
+
+install_config {
+	<config>
+		<parent-provides>
+			<service name="ROM"/>
+			<service name="RAM"/>
+			<service name="CPU"/>
+			<service name="RM"/>
+			<service name="CAP"/>
+			<service name="PD"/>
+			<service name="SIGNAL"/>
+			<service name="LOG"/>
+		</parent-provides>
+		<default-route>
+			<any-service> <parent/> </any-service>
+		</default-route>
+		<start name="test-printf">
+			<resource name="RAM" quantum="10M"/>
+		</start>
+	</config>
+}
+
+build_boot_image "core init test-printf"
+
+append qemu_args "-nographic -m 64"
+
+run_genode_until {-1 = -1 = -1} 10
+
+puts "Test succeeded"

base/src/base/console/console.cc

@@ -276,7 +276,7 @@ void Console::vprintf(const char *format, va_list list)
 				case Format_command::LONG:
 
 					numeric_arg = (cmd.type == Format_command::UINT) ?
-						va_arg(list, unsigned long) : va_arg(list, long);
+						(long long)va_arg(list, unsigned long) : va_arg(list, long);
 					break;
 
 				case Format_command::SIZE_T:
@@ -287,7 +287,7 @@ void Console::vprintf(const char *format, va_list list)
 				case Format_command::DEFAULT:
 
 					numeric_arg = (cmd.type == Format_command::UINT) ?
-						va_arg(list, unsigned int) : va_arg(list, int);
+						(long long)va_arg(list, unsigned int) : va_arg(list, int);
 					break;
 			}
 		}

base/src/test/printf/main.cc

@@ -0,0 +1,22 @@
+/*
+ * \brief  Testing 'printf()' with negative integer
+ * \author Christian Prochaska
+ * \date   2012-04-20
+ *
+ */
+
+/*
+ * Copyright (C) 2012 Genode Labs GmbH
+ *
+ * This file is part of the Genode OS framework, which is distributed
+ * under the terms of the GNU General Public License version 2.
+ */
+
+#include <base/printf.h>
+
+int main(int argc, char **argv)
+{
+	Genode::printf("-1 = %d = %ld\n", -1, -1L);
+
+	return 0;
+}

base/src/test/printf/target.mk

@@ -0,0 +1,3 @@
+TARGET   = test-printf
+SRC_CC   = main.cc
+LIBS     = env