LUA_INLINE int lua_compare(lua_State* L, int index1, int index2, int op)
{
if (op == LUA_OPEQ) {
return lua_equal(L, index1, index2);
} else if (op == LUA_OPLT) {
return lua_lessthan(L, index1, index2);
} else if (op == LUA_OPLE) {
return lua_lessthan(L, index1, index2) || lua_equal(L, index1, index2);
} else {
return 0;
}
}
LUA_API int
lua_compare(lua_State *L, int idx1, int idx2, int op) {
switch(op) {
case LUA_OPEQ:
return lua_equal(L,idx1,idx2);
case LUA_OPLT:
return lua_lessthan(L, idx1, idx2);
case LUA_OPLE:
return !lua_lessthan(L, idx2, idx1);
}
assert(0);
return 0;
}
int lessthan(lua_State * L, int idx1, int idx2) {
#if LUA_VERSION_NUM < 502
return lua_lessthan(L, idx1, idx2);
#else
return lua_compare(L, idx1, idx2, LUA_OPLT);
#endif
}
// __lt (less-than) metamethod handler
// Provided so that a list of localised strings can be sorted, which is used
// to create nice user-interface listing of strings. Note that this will mean
// that persist->change language->depersist will result in a "random" ordering
// of the resulting list, but this is generally acceptable.
static int l_str_lt(lua_State *L)
{
luaL_checkany(L, 1);
luaL_checkany(L, 2);
lua_settop(L, 2);
aux_push_weak_table(L, 0);
lua_pushvalue(L, 1);
lua_rawget(L, 3);
lua_pushvalue(L, 2);
lua_rawget(L, 3);
lua_pushboolean(L, lua_lessthan(L, 4, 5));
return 1;
}
static int sort_comp (lua_State *L, int a, int b) {
if (!lua_isnil(L, 2)) { /* function? */
int res;
lua_pushvalue(L, 2);
lua_pushvalue(L, a-1); /* -1 to compensate function */
lua_pushvalue(L, b-2); /* -2 to compensate function and `a' */
lua_call(L, 2, 1);
res = lua_toboolean(L, -1);
lua_pop(L, 1);
return res;
}
else /* a < b? */
return lua_lessthan(L, a, b);
}
static int sort_comp (lua_State *L, int a, int b) {
/* WARNING: the caller (auxsort) must ensure stack space */
if (!lua_isnil(L, 2)) { /* function? */
int res;
lua_pushvalue(L, 2);
lua_pushvalue(L, a-1); /* -1 to compensate function */
lua_pushvalue(L, b-2); /* -2 to compensate function and `a' */
lua_rawcall(L, 2, 1);
res = !lua_isnil(L, -1);
lua_pop(L, 1);
return res;
}
else /* a < b? */
return lua_lessthan(L, a, b);
}
int lua_compare (lua_State *L, int idx1, int idx2, int op) {
int result = 0;
switch (op) {
case LUA_OPEQ:
return lua_equal(L, idx1, idx2);
case LUA_OPLT:
return lua_lessthan(L, idx1, idx2);
case LUA_OPLE:
luaL_checkstack(L, 5, "not enough stack slots");
idx1 = lua_absindex(L, idx1);
idx2 = lua_absindex(L, idx2);
lua_pushvalue(L, idx1);
lua_pushvalue(L, idx2);
compat52_call_lua(L, compat52_compare_code,
sizeof(compat52_compare_code)-1, 2, 1);
result = lua_toboolean(L, -1);
lua_pop(L, 1);
return result;
default:
luaL_error(L, "invalid 'op' argument for lua_compare");
}
return 0;
}
JNIEXPORT jint JNICALL Java_m_lua_Lua_lessthan
(JNIEnv* env, jobject thiz, jlong nativeObj, jint idx1, jint idx2) {
pushJNIEnv(env, nativeObj);
return (jint) lua_lessthan((lua_State*) nativeObj, idx1, idx2);
}
