thenumbernine/preproc-lua

C preprocessor in Lua

Useful for luajit ffi cdefs just straight up using the .h files

Depends on:

`make_all.lua`

This generates a specific luajit loader file for a specific C include file. It accepts either a specific header listed in the include-list, or it can generate all provided at once. This is separate of generate.lua because I need to use separate luajit ffi cdef states, so I just use separate processes.

This is close to becoming what the include-lua project intended to be. However if you look inside the include-list you will see the amount of hand-tuning still required for this to work. Until that can all be automated, include-lua will be on the shelf for a while.

`include-list.lua`

This contains a list of C to Lua files. It is used for automatic generation of all files. It is also used for determining when to replace an included file with a previously-generated file.

`generate.lua`

This file generates stripped header files from C header files. The stripped headers are specific to LuaJIT: -) They have #define constants replaced with enum{}'s. -) They have function prototypes preserved.

luajit generate.lua <optional-args> <include-file1> <include-file2> ...

optional-args: - -I = add extra include directory search path - -M[=] = add extra macro - -silent = include the specified file, but do not include its contents in the header generation. - -skip = don't include the specified file.

`preproc.lua`

This is the lua file for preprocessor class.

process a single file:

local Preproc = require 'preproc'
print(Preproc(code))

process a single file with some options:

local Preproc = require 'preproc'
print(Preproc{
	code = code,
	includeDirs = {...},
	macros = {...},
})

process multiple files:

local Preproc = require 'preproc'
local preproc = Preproc()
print(preproc{
	code = '#include <file1.h>',
	macros = ...,
	includeDirs = ...,
})
print(preproc{
	code = '#include <file2.h>',
	macros = ...,
	includeDirs = ...,
})

or modify the state as we go:

preproc:setMacros{
	KEY1 = 'value1',
	KEY2 = 'value2',
	...
}
preproc:addIncludeDir'path/too/foo/bar.h'
preproc:addIncludeDirs{
	'dir1/file1.h',
	'dir2/file2.h',
	...
}

returns an object that is cast to its .code field which contains the result. this way you can query the .macros, .alreadyIncludedFiles, etc after preprocessing

processing multiple files retains the state of .macros and .alreadyIncludedFiles.

the call() operator returns the last file processed.

TODO should .code hold the last file processed, or the total files processed?

TODO If I'm in the middle of a typedef or enum or something with {}'s, I should wait to insert the #define => enum{} code. (pthread.h)

TODO if you have a number value like enum {A = 0}; then do recursive def #define A A, which because it's a number value is turned into an enum, then this will still insert that second enum. (pthread.h)

Windows

Right now this whole setup is made specifically for Linux. I'm slowly working towards Windows support as well, and with that means a giant cross-platform cross-arch include file repository.

thenumbernine / preproc-lua