IDLC

$ sudo apt install cmake build-essential g++ curl unzip tar python

Before the first build, run ./setup in the project root.

idlc uses CMake:

$ mkdir build
$ cd build
$ cmake ..
$ make

$ idlc foo.idl

will generate from the IDL a set of files:

• client.c
• server.c
• common.c
• trampolines.lds.S
• common.h

Both driver and kernel side must be built with common.c and trampolines.lds.S; server.c must be linked kernel-side, and client.c, driver-side. The generated code expects a glue_user.h header in the same directory as the generated sources, into which you should put any includes or defines needed by the prototypes of the driver / kernel interface. The generated code makes calls to glue_user_* functions (these implement environment-specific implementations of tracing, shadow tracking, or RPC message delivery), which must be defined and linked by both sides. The nullnet_gen driver in the nullnet_gen branch of lvd-linux has a mostly complete set of implementations in glue_user.c, which should be usable as a drop-in implementation in any other LVD driver.

You will also need to implement the KLCD dispatch loop and the LVDs handle_rpc_calls dispatcher, an implementation of the former of wich you'll find in nullnet_gen/net_klcd/main.c.

Currently one manual modification is always required: the LVD requires certain init / exit calls (i.e. __dummy_lcd_init() in nullnet), and you will have to add RPC_IDs for these in common.h and handle them explicitly in your dispatch loop code. Note also that glue_user_init() in the existing glue_user.c must be called by both sides before the glue layer can track shadows, as this call initializes the employed hashmaps.

Therefore, what nullnet_gen modifies manually is as follows:

• Adding MODULE_INIT and MODULE_EXIT RPC_IDs
• Adding switch cases to the driver-side (i.e. client-side) dispatch code (in nullnet_gen/client.c:try_dispatch) to handle these and call __dummy_lcd_init() and __dummy_lcd_exit(), respectively
• Calling glue_user_init() in the module init functions of both the KLCD and LCD before any RPC calls
  • Refer to nullnet_gen/net_klcd/main.c:99 and nullnet_gen/dummy_lcd/main.c:74