/*=========================================================================*\
* Auxiliar routines for class hierarchy manipulation
* LuaSocket toolkit
\*=========================================================================*/
#include "luasocket.h"
#include "auxiliar.h"
#include <string.h>
#include <stdio.h>
/*-------------------------------------------------------------------------*\
* Initializes the module
\*-------------------------------------------------------------------------*/
int auxiliar_open(lua_State *L) {
(void) L;
return 0;
}
/*-------------------------------------------------------------------------*\
* Creates a new class with given methods
* Methods whose names start with __ are passed directly to the metatable.
\*-------------------------------------------------------------------------*/
void auxiliar_newclass(lua_State *L, const char *classname, luaL_Reg *func) {
luaL_newmetatable(L, classname); /* mt */
/* create __index table to place methods */
lua_pushstring(L, "__index"); /* mt,"__index" */
lua_newtable(L); /* mt,"__index",it */
/* put class name into class metatable */
lua_pushstring(L, "class"); /* mt,"__index",it,"class" */
lua_pushstring(L, classname); /* mt,"__index",it,"class",classname */
lua_rawset(L, -3); /* mt,"__index",it */
/* pass all methods that start with _ to the metatable, and all others
* to the index table */
for (; func->name; func++) { /* mt,"__index",it */
lua_pushstring(L, func->name);
lua_pushcfunction(L, func->func);
lua_rawset(L, func->name[0] == '_' ? -5: -3);
}
lua_rawset(L, -3); /* mt */
lua_pop(L, 1);
}
/*-------------------------------------------------------------------------*\
* Prints the value of a class in a nice way
\*-------------------------------------------------------------------------*/
int auxiliar_tostring(lua_State *L) {
char buf[32];
if (!lua_getmetatable(L, 1)) goto error;
lua_pushstring(L, "__index");
lua_gettable(L, -2);
if (!lua_istable(L, -1)) goto error;
lua_pushstring(L, "class");
lua_gettable(L, -2);
if (!lua_isstring(L, -1)) goto error;
sprintf(buf, "%p", lua_touserdata(L, 1));
lua_pushfstring(L, "%s: %s", lua_tostring(L, -1), buf);
return 1;
error:
lua_pushstring(L, "invalid object passed to 'auxiliar.c:__tostring'");
lua_error(L);
return 1;
}
/*-------------------------------------------------------------------------*\
* Insert class into group
\*-------------------------------------------------------------------------*/
void auxiliar_add2group(lua_State *L, const char *classname, const char *groupname) {
luaL_getmetatable(L, classname);
lua_pushstring(L, groupname);
lua_pushboolean(L, 1);
lua_rawset(L, -3);
lua_pop(L, 1);
}
/*-------------------------------------------------------------------------*\
* Make sure argument is a boolean
\*-------------------------------------------------------------------------*/
int auxiliar_checkboolean(lua_State *L, int objidx) {
if (!lua_isboolean(L, objidx))
auxiliar_typeerror(L, objidx, lua_typename(L, LUA_TBOOLEAN));
return lua_toboolean(L, objidx);
}
/*-------------------------------------------------------------------------*\
* Return userdata pointer if object belongs to a given class, abort with
* error otherwise
\*-------------------------------------------------------------------------*/
void *auxiliar_checkclass(lua_State *L, const char *classname, int objidx) {
void *data = auxiliar_getclassudata(L, classname, objidx);
if (!data) {
char msg[45];
sprintf(msg, "%.35s expected", classname);
luaL_argerror(L, objidx, msg);
}
return data;
}
/*-------------------------------------------------------------------------*\
* Return userdata pointer if object belongs to a given group, abort with
* error otherwise
\*-------------------------------------------------------------------------*/
void *auxiliar_checkgroup(lua_State *L, const char *groupname, int objidx) {
void *data = auxiliar_getgroupudata(L, groupname, objidx);
if (!data) {
char msg[45];
sprintf(msg, "%.35s expected", groupname);
luaL_argerror(L, objidx, msg);
}
return data;
}
/*-------------------------------------------------------------------------*\
* Set object class
\*-------------------------------------------------------------------------*/
void auxiliar_setclass(lua_State *L, const char *classname, int objidx) {
luaL_getmetatable(L, classname);
if (objidx < 0) objidx--;
lua_setmetatable(L, objidx);
}
/*-------------------------------------------------------------------------*\
* Get a userdata pointer if object belongs to a given group. Return NULL
* otherwise
\*-------------------------------------------------------------------------*/
void *auxiliar_getgroupudata(lua_State *L, const char *groupname, int objidx) {
if (!lua_getmetatable(L, objidx))
return NULL;
lua_pushstring(L, groupname);
lua_rawget(L, -2);
if (lua_isnil(L, -1)) {
lua_pop(L, 2);
return NULL;
} else {
lua_pop(L, 2);
return lua_touserdata(L, objidx);
}
}
/*-------------------------------------------------------------------------*\
* Get a userdata pointer if object belongs to a given class. Return NULL
* otherwise
\*-------------------------------------------------------------------------*/
void *auxiliar_getclassudata(lua_State *L, const char *classname, int objidx) {
return luaL_testudata(L, objidx, classname);
}
/*-------------------------------------------------------------------------*\
* Throws error when argument does not have correct type.
* Used to be part of lauxlib in Lua 5.1, was dropped from 5.2.
\*-------------------------------------------------------------------------*/
int auxiliar_typeerror (lua_State *L, int narg, const char *tname) {
const char *msg = lua_pushfstring(L, "%s expected, got %s", tname,
luaL_typename(L, narg));
return luaL_argerror(L, narg, msg);
}