cdbus-codegen

#!/usr/bin/env lua
-- cdbus-codegen - generate cdbus bindings from dbus xml files
-- SPDX-FileCopyrightText: Copyright © 2023 Nedko Arnaudov
-- SPDX-License-Identifier: GPL-3

local lxp = require('lxp')
local table = require('table')

interfaces = {}

local interface
local callable

cdbus_codegen = {}

cdbus_codegen.StartElement = function (parser, name, attr)
  if (name == "interface") then
    interface = {}
    interface.name = attr['name']
--    interface.attr = attr
--    for k, v in pairs(attr) do print("  ", k, v1) end
  end
  if (name == "method") then
    callable = {}
    callable.typestr = name
    callable.name = attr['name']:gsub("%s+", "")
    --print("method", interface.name, callable.name)
    --for k, v in pairs(attr) do print("  ", k, v1) end
  end
  if (name == "signal") then
    callable = {}
    callable.typestr = name
    callable.name = attr['name']
    --print("signal", interface.name, signal.name)
  end
  local arg
  if (name == "arg") then
    arg = {}
    if attr.name then arg.name = attr.name end
    arg.type = attr.type
    arg.direction = attr.direction
    --print("   arg", arg.name, arg.type, arg.direction)
    callable.args = callable.args or {}
    callable.args[#callable.args + 1] = arg
  end
end

cdbus_codegen.EndElement = function (parser, name)
  if (name == "interface") then
    interfaces[interface.name] = interface
    interface = nil
  end
  if (name == "method") then
    interface.methods = interface.methods or {}
    interface.methods[#interface.methods + 1] = callable
    interface.callables = interface.callables or {}
    interface.callables[#interface.callables + 1] = callable
    callable = nil
  end
  if (name == "signal") then
    interface.signals = interface.signals or {}
    interface.signals[#interface.signals + 1] = callable
    interface.callables = interface.callables or {}
    interface.callables[#interface.callables + 1] = callable
    callable = nil
  end
end

p = lxp.new(cdbus_codegen)

for l in io.lines() do  -- iterate lines
    p:parse(l)          -- parses the line
--    p:parse("\n")       -- parses the end of line
end
p:parse()               -- finishes the document
p:close()               -- closes the parser

for name, iface in pairs(interfaces) do
  --print(("interface: \"%s\""):format(name))
  for _, callable in pairs(iface.callables) do
    local rettype
    local argtokens = {}
    if callable.args then
      for _, arg in ipairs(callable.args) do
        if not arg.name and arg.direction == "out" then
          rettype = arg.type
        else
          argtokens[#argtokens + 1] = ("%s %s %s"):format(arg.name, arg.type, arg.direction)
        end
      end
    end
    if callable.typestr == "method" then rettype = "void" end
    if rettype then rettype = " => " .. rettype else rettype = "" end
    --print(("%s %s(%s)%s"):format(callable.typestr, callable.name, table.concat(argtokens, ", "), rettype))
  end
end

print("/* This data is GENERATED from D-Bus interface description XML")
print(" * Edit by hand only if you know what you are doing */")
print()

namespace = tostring(arg[1]) .. "_cdbus_"

for name, iface in pairs(interfaces) do
  for _, callable in pairs(iface.callables) do
    local typestr2
    local direction2
    if callable.typestr == "method" then
      typestr2 = "METHOD"
    elseif callable.typestr == "signal" then
      typestr2 = "SIGNAL"
    end
    print(("CDBUS_%s_ARGS_BEGIN(%s, \"\")"):format(typestr2, callable.name))
    if callable.args then
      for _, arg in ipairs(callable.args) do
        if arg.name then
          if callable.typestr == "method" then
            typestr2 = "METHOD"
            direction2 = "_" .. arg.direction:upper()
          elseif callable.typestr == "signal" then
            typestr2 = "SIGNAL"
            direction2 = ""
          end
          print(("  CDBUS_%s_ARG_DESCRIBE%s(\"%s\", \"%s\", \"\")"): format(typestr2, direction2, arg.name, arg.type))
        end
      end
    end
    print(("CDBUS_%s_ARGS_END"):format(typestr2))
    print()
  end

  print("CDBUS_METHODS_BEGIN")
  for _, method in ipairs(iface.methods) do
    print("CDBUS_METHOD_DESCRIBE(" .. method.name .. ", " .. namespace .. method.name .. "_dbus)")
  end
  print("CDBUS_METHODS_END")
  print()

  if iface.signals then
    print("CDBUS_SIGNALS_BEGIN")
    for _, signal in ipairs(iface.signals) do
      print("CDBUS_SIGNAL_DESCRIBE(" .. signal.name .. ")")
    end
    print("CDBUS_SIGNALS_END")
  end
  print()

  local iface_varname = namespace .. "interface_" .. iface.name:gsub("%.", "_")
  local iface_name_define = namespace:upper() .. "IFACE_" .. iface.name:gsub("%.", "_"):upper()

  print("#define " .. iface_name_define .. " \"" .. iface.name .. "\"")
  print()

  if not iface.signals then
    print(("CDBUS_INTERFACE_DEFAULT_HANDLER_METHODS_ONLY(%s, %s)"):format(iface_varname, iface_name_define))
  else
    print(("CDBUS_INTERFACE_DEFAULT_HANDLER_METHODS_AND_SIGNALS(%s, %s)"):format(iface_varname, iface_name_define))
  end
end