toolchain: add a program for compiling ipc interface definitions

ifc can be used to compile .if files into self-contained header-only C
libraries, which can be used to send/receive messages that conform
to the described interface.

toolchain/ifc/msg.h

@@ -0,0 +1,41 @@
+#ifndef IFC_MSG_H_
+#define IFC_MSG_H_
+
+#include <blue/core/queue.h>
+
+struct type;
+
+struct msg_parameter {
+	char *p_name;
+	const struct type *p_type;
+	b_queue_entry p_entry;
+};
+
+struct msg_definition {
+	char *msg_name;
+	b_queue_entry msg_entry;
+
+	b_queue msg_params;
+	b_queue msg_results;
+};
+
+extern struct msg_definition *msg_definition_create(const char *name);
+extern void msg_definition_destroy(struct msg_definition *msg);
+
+extern bool msg_definition_has_param(
+	struct msg_definition *msg,
+	const char *name);
+extern bool msg_definition_has_result(
+	struct msg_definition *msg,
+	const char *name);
+
+extern int msg_definition_add_param(
+	struct msg_definition *msg,
+	const struct type *type,
+	const char *name);
+extern int msg_definition_add_result(
+	struct msg_definition *msg,
+	const struct type *type,
+	const char *name);
+
+#endif