#include <stdio.h>
#include <string.h>
#include "safer-api.h"
/* *********************************************************************
* Transforming Haskell errors to Lua errors
* *********************************************************************/
void hslua_pushhaskellerr(lua_State *L)
{
lua_getglobal(L, "_HASKELLERR");
}
/* Error handling */
int hslua_call_hs(lua_State *L)
{
int nargs = lua_gettop(L);
/* Push HaskellImportFunction and call the underlying function */
lua_pushvalue(L, lua_upvalueindex(1));
lua_insert(L, 1);
lua_call(L, nargs, LUA_MULTRET);
/* Check whether an error value was returned */
int nres = lua_gettop(L);
/* We signal an error on the haskell side by passing two values: the special
* haskellerr object and the error message.
*/
if (nres == 2) {
hslua_pushhaskellerr(L);
int is_err = lua_rawequal(L, 0 + 1, -1);
lua_pop(L, 1); /* pop haskellerr used for equality test */
if (is_err) {
lua_remove(L, 1); /* remove returned haskellerr */
return lua_error(L);
}
}
return nres;
}
/* *********************************************************************
* Transforming Lua errors to Haskell errors
* *********************************************************************/
/* compare */
#if LUA_VERSION_NUM >= 502
int hslua__compare(lua_State *L)
{
int op = lua_tointeger(L, 3);
int res = lua_compare(L, 1, 2, op);
lua_pushinteger(L, res);
return 1;
}
int hslua_compare(lua_State *L, int index1, int index2, int op)
{
index1 = lua_absindex(L, index1);
index2 = lua_absindex(L, index2);
lua_pushcfunction(L, hslua__compare);
lua_pushvalue(L, index1);
lua_pushvalue(L, index2);
lua_pushinteger(L, op);
int callres = lua_pcall(L, 3, 1, 0);
if (callres != 0) {
return -callres;
}
int res = lua_tointeger(L, -1);
lua_pop(L, 1);
return res;
}
#endif
/* concat */
int hslua__concat(lua_State *L)
{
lua_concat(L, lua_gettop(L));
return 1;
}
int hslua_concat(lua_State *L, int n)
{
lua_pushcfunction(L, hslua__concat);
lua_insert(L, -n - 1);
return -lua_pcall(L, n, 1, 0);
}
/* getfield */
int hslua__getfield(lua_State *L)
{
const char *k = lua_tostring(L, 2);
lua_getfield(L, 1, k);
return 1;
}
int hslua_getfield(lua_State *L, int index, const char *k)
{
lua_pushvalue(L, index);
lua_pushlstring(L, k, strlen(k));
lua_pushcfunction(L, hslua__getfield);
lua_insert(L, -3);
return -lua_pcall(L, 2, 1, 0);
}
/* getglobal */
int hslua__getglobal(lua_State *L)
{
const char *name = lua_tostring(L, 1);
#if LUA_VERSION_NUM >= 502
lua_getglobal(L, name);
#else
lua_getfield(L, LUA_GLOBALSINDEX, name);
#endif
return 1;
}
int hslua_getglobal(lua_State *L, const char *name)
{
lua_pushcfunction(L, hslua__getglobal);
lua_pushlstring(L, name, strlen(name));
return -lua_pcall(L, 1, 1, 0);
}
/* gettable */
int hslua__gettable(lua_State *L)
{
lua_pushvalue(L, 1);
lua_gettable(L, 2);
return 1;
}
int hslua_gettable(lua_State *L, int index)
{
lua_pushvalue(L, index);
lua_pushcfunction(L, hslua__gettable);
lua_insert(L, -3);
return -lua_pcall(L, 2, 1, 0);
}
/* setfield */
int hslua__setfield(lua_State *L)
{
const char *k = lua_tostring(L, 3);
lua_pushvalue(L, 1);
lua_setfield(L, 2, k);
return 0;
}
int hslua_setfield(lua_State *L, int index, const char *k)
{
lua_pushvalue(L, index);
lua_pushlstring(L, k, strlen(k));
lua_pushcfunction(L, hslua__setfield);
lua_insert(L, -4);
return -lua_pcall(L, 3, 0, 0);
}
/* setglobal */
int hslua__setglobal(lua_State *L)
{
const char *name = lua_tostring(L, 2);
lua_pushvalue(L, 1);
#if LUA_VERSION_NUM >= 502
lua_setglobal(L, name);
#else
lua_setfield(L, LUA_GLOBALSINDEX, name);
#endif
return 0;
}
int hslua_setglobal(lua_State *L, const char *name)
{
lua_pushlstring(L, name, strlen(name));
lua_pushcfunction(L, hslua__setglobal);
lua_insert(L, -3);
return -lua_pcall(L, 2, 0, 0);
}
/* settable */
int hslua__settable(lua_State *L)
{
lua_pushvalue(L, 1);
lua_pushvalue(L, 2);
lua_settable(L, 3);
return 0;
}
int hslua_settable(lua_State *L, int index)
{
lua_pushvalue(L, index);
lua_pushcfunction(L, hslua__settable);
lua_insert(L, -4);
return -lua_pcall(L, 3, 0, 0);
}
/* next */
int hslua__next(lua_State *L)
{
lua_pushvalue(L, 1);
return lua_next(L, 2) ? 2 : 0;
}
int hslua_next(lua_State *L, int index)
{
int oldsize = lua_gettop(L);
lua_pushvalue(L, index);
lua_pushcfunction(L, hslua__next);
lua_insert(L, -3);
int res = lua_pcall(L, 2, LUA_MULTRET, 0);
if (res != 0) {
/* error */
return (- res);
}
/* success */
return (lua_gettop(L) - oldsize + 1); /* correct for popped value */
}