[dhcp] Include gPXE version number within DHCP request

src/Makefile

 VERSION		= $(MM_VERSION).$(VERSION_PATCH)$(EXTRAVERSION)
 CFLAGS		+= -DVERSION_MAJOR=$(VERSION_MAJOR) \
 		   -DVERSION_MINOR=$(VERSION_MINOR) \
+		   -DVERSION_PATCH=$(VERSION_PATCH) \
 		   -DVERSION=\"$(VERSION)\"
 IDENT		= '$(@F) $(VERSION) (GPL) etherboot.org'
 version :

src/include/gpxe/dhcp.h

  */
 #define DHCP_EB_REVERSE_PASSWORD DHCP_ENCAP_OPT ( DHCP_EB_ENCAP, 0xc1 )
 
+/** gPXE version number */
+#define DHCP_EB_VERSION DHCP_ENCAP_OPT ( DHCP_EB_ENCAP, 0xeb )
+
 /** iSCSI primary target IQN */
 #define DHCP_ISCSI_PRIMARY_TARGET_IQN 201
 

src/include/gpxe/features.h

 /** @} */
 
 /** Declare a feature code for DHCP */
-#define __dhcp_feature( category )					    \
-	 __table ( uint8_t, dhcp_features, category )
+#define __dhcp_feature __table ( uint8_t, dhcp_features, 01 )
 
 /** Construct a DHCP feature table entry */
-#define DHCP_FEATURE( category, feature_opt, version )			    \
-	_DHCP_FEATURE ( category, OBJECT, feature_opt, version )
-#define _DHCP_FEATURE( category, _name, feature_opt, version )		    \
-	__DHCP_FEATURE ( category, _name, feature_opt, version )
-#define __DHCP_FEATURE( category, _name, feature_opt, version )		    \
-	uint8_t __dhcp_feature_ ## _name [] __dhcp_feature ( category ) = { \
-		feature_opt, DHCP_BYTE ( version )			    \
+#define DHCP_FEATURE( feature_opt, ... )				    \
+	_DHCP_FEATURE ( OBJECT, feature_opt, __VA_ARGS__ )
+#define _DHCP_FEATURE( _name, feature_opt, ... )			    \
+	__DHCP_FEATURE ( _name, feature_opt, __VA_ARGS__ )
+#define __DHCP_FEATURE( _name, feature_opt, ... )			    \
+	uint8_t __dhcp_feature_ ## _name [] __dhcp_feature = {		    \
+		feature_opt, DHCP_OPTION ( __VA_ARGS__ )		    \
 	};
 
 /** A named feature */
 /** Declare a feature */
 #define FEATURE( category, text, feature_opt, version )			    \
 	FEATURE_NAME ( category, text );				    \
-	DHCP_FEATURE ( category, feature_opt, version );
+	DHCP_FEATURE ( feature_opt, version );
+
+/** Declare the version number feature */
+#define FEATURE_VERSION( ... )						    \
+	DHCP_FEATURE ( DHCP_ENCAPSULATED ( DHCP_EB_VERSION ), __VA_ARGS__ )
 
 #endif /* _GPXE_FEATURES_H */

src/net/udp/dhcp.c

 #include <gpxe/dhcp.h>
 #include <gpxe/dhcpopts.h>
 #include <gpxe/dhcppkt.h>
+#include <gpxe/features.h>
 
 /** @file
  *
 static uint8_t dhcp_features[0] __table_start ( uint8_t, dhcp_features );
 static uint8_t dhcp_features_end[0] __table_end ( uint8_t, dhcp_features );
 
+/** Version number feature */
+FEATURE_VERSION ( VERSION_MAJOR, VERSION_MINOR, VERSION_PATCH );
+
 /** DHCP network device descriptor */
 struct dhcp_netdev_desc {
 	/** Bus type ID */