nodemcu-firmware/components/base_nodemcu/include/module.h

95 lines
3.6 KiB
C

#ifndef __MODULE_H__
#define __MODULE_H__
#include "sdkconfig.h"
#include "lrotable.h"
/* Registering a module within NodeMCU is really easy these days!
*
* Most of the work is done by a combination of pre-processor, compiler
* and linker "magic". Gone are the days of needing to update 4+ separate
* files just to register a module!
*
* You will need:
* - to include this header
* - a name for the module
* - a LUA_REG_TYPE module map
* - optionally, an init function
*
* Then simply put a line like this at the bottom of your module file:
*
* NODEMCU_MODULE(MYNAME, "myname", myname_map, luaopen_myname);
*
* or perhaps
*
* NODEMCU_MODULE(MYNAME, "myname", myname_map, NULL);
*
* if you don't need an init function.
*
* When you've done this, you can simply add a Kconfig entry for the module
* to control whether it gets linked in or not. With it linked in, you can
* then within NodeMCU access it with myname.foo(), assuming you have
* a foo function in your module.
*/
#define MODULE_EXPAND_(x) x
#define MODULE_PASTE_(x,y) x##y
#define MODULE_EXPAND_PASTE_(x,y) MODULE_PASTE_(x,y)
#ifdef LUA_CROSS_COMPILER
#ifdef _MSC_VER
//on msvc it is necessary to go through more pre-processor hoops to get the
//section name built; string merging does not happen in the _declspecs.
//NOTE: linker magic is invoked via the magical '$' character. Caveat editor.
#define __TOKIFY(s) .rodata1$##s
#define __TOTOK(s) __TOKIFY(s)
#define __STRINGIFY(x) #x
#define __TOSTRING(x) __STRINGIFY(x)
#define __ROSECNAME(s) __TOSTRING(__TOTOK(s))
#define LOCK_IN_SECTION(s) __declspec ( allocate( __ROSECNAME(s) ) )
#else
#define LOCK_IN_SECTION(s) __attribute__((used,unused,section(".rodata1." #s)))
#endif
#else
#define LOCK_IN_SECTION(s) __attribute__((used,unused,section(".lua_" #s)))
#endif
/* For the ROM table, we name the variable according to ( | denotes concat):
* cfgname | _module_selected | CONFIG_LUA_MODULE_##cfgname
* where the CONFIG_LUA_MODULE_XYZ macro is first expanded to yield either
* an empty string (or 1) if the module has been enabled, or the literal
* CONFIG_LUA_MODULE_XYZ in the case it hasn't. Thus, the name of the variable
* ends up looking either like XYZ_module_enabled, or if not enabled,
* XYZ_module_enabledCONFIG_LUA_MODULE_XYZ. This forms the basis for
* letting the build system detect automatically (via nm) which modules need
* to be linked in.
*/
#define NODEMCU_MODULE(cfgname, luaname, map, initfunc) \
const LOCK_IN_SECTION(libs) \
luaR_entry MODULE_PASTE_(lua_lib_,cfgname) = { luaname, LRO_FUNCVAL(initfunc) }; \
const LOCK_IN_SECTION(rotable) \
luaR_entry MODULE_EXPAND_PASTE_(cfgname,MODULE_EXPAND_PASTE_(_module_selected,MODULE_PASTE_(CONFIG_LUA_MODULE_,cfgname))) \
= {luaname, LRO_ROVAL(map ## _map)}
#endif
// helper stringing macros
#define xstr(s) str(s)
#define str(s) #s
// EXTMODNAME is injected by the generated component.mk
#ifdef EXTMODNAME
#define MODNAME xstr(EXTMODNAME)
#else
#define MODNAME "module"
#endif
// use NODEMCU_MODULE_METATABLE() to generate a unique metatable name for your objects:
#define NODEMCU_MODULE_METATABLE() MODULE_EXPAND_(MODNAME xstr(__COUNTER__))
// NODEMCU_MODULE_STD() defines the entry points for an external module:
#define NODEMCU_MODULE_STD() \
static const LOCK_IN_SECTION(libs) \
luaR_entry lua_lib_module = {MODNAME, LRO_FUNCVAL(module_init)}; \
const LOCK_IN_SECTION(rotable) \
luaR_entry MODULE_EXPAND_PASTE_(EXTMODNAME, _entry) = {MODNAME, LRO_ROVAL(module_map)};