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Get rid of the write mode field table in metamethods.
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Two separate tables can be confusing, e.g. if a builtin field
overrides a writable custom one only in the read table.
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@angavrilov
angavrilov committed Mar 23, 2012
1 parent ead28db commit ccc8fac
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Showing 3 changed files with 60 additions and 67 deletions.
3 changes: 3 additions & 0 deletions depends/lua/CMakeLists.txt
View file
Original file line number Diff line number Diff line change
@@ -1,6 +1,9 @@
PROJECT ( lua C )
CMAKE_MINIMUM_REQUIRED(VERSION 2.8)

# TODO: make this RelWithDebInfo only
ADD_DEFINITIONS(-DLUA_USE_APICHECK)

IF(WIN32)
ADD_DEFINITIONS(-D_CRT_SECURE_NO_DEPRECATE )
ELSE()
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123 changes: 57 additions & 66 deletions library/LuaWrapper.cpp
View file
Original file line number Diff line number Diff line change
Expand Up @@ -127,7 +127,7 @@ static void field_error(lua_State *state, int index, const char *err, const char
{
lua_getfield(state, UPVAL_METATABLE, "__metatable");
const char *cname = lua_tostring(state, -1);
const char *fname = lua_tostring(state, index);
const char *fname = index ? lua_tostring(state, index) : "*";
luaL_error(state, "Cannot %s field %s.%s: %s.",
mode, (cname ? cname : "?"), (fname ? fname : "?"), err);
}
Expand Down Expand Up @@ -335,6 +335,14 @@ static void freeze_table(lua_State *state, bool leave_metatable = false, const c
lua_pop(state, 1);
}

static void LookupInTable(lua_State *state, const char *tname)
{
lua_getfield(state, LUA_REGISTRYINDEX, tname);
lua_swap(state);
lua_rawget(state, -2);
lua_remove(state, -2);
}

/**
* Look up the key on the stack in DFHACK_TYPETABLE;
* if found, put result on the stack and return true.
Expand All @@ -349,10 +357,7 @@ static bool LookupTypeInfo(lua_State *state, bool in_method)
}
else
{
lua_getfield(state, LUA_REGISTRYINDEX, DFHACK_TYPETABLE_NAME);
lua_swap(state);
lua_rawget(state, -2);
lua_remove(state, -2);
LookupInTable(state, DFHACK_TYPETABLE_NAME);
}

// stack: [info]
Expand Down Expand Up @@ -556,7 +561,7 @@ static uint8_t *get_object_addr(lua_State *state, int obj, int field, const char
!lua_getmetatable(state, obj))
field_error(state, field, "invalid object", mode);

if (!lua_equal(state, -1, UPVAL_METATABLE))
if (!lua_rawequal(state, -1, UPVAL_METATABLE))
field_error(state, field, "invalid object metatable", mode);

lua_pop(state, 1);
Expand Down Expand Up @@ -697,6 +702,8 @@ static int meta_struct_newindex(lua_State *state)
{
uint8_t *ptr = get_object_addr(state, 1, 2, "write");
auto field = (struct_field_info*)find_field(state, 2, "write");
if (!field)
field_error(state, 2, "builtin property", "write");
write_field(state, field, ptr + field->offset, 3);
return 0;
}
Expand All @@ -722,6 +729,8 @@ static int meta_primitive_newindex(lua_State *state)
{
uint8_t *ptr = get_object_addr(state, 1, 2, "write");
auto type = (type_identity*)find_field(state, 2, "write");
if (!type)
field_error(state, 2, "builtin property", "write");
type->lua_write(state, 2, ptr, 3);
return 0;
}
Expand All @@ -744,15 +753,18 @@ static int meta_container_len(lua_State *state)
* - Numbers are indices and handled directly.
* - NULL userdata are metafields; push and exit;
*/
static int lookup_container_field(lua_State *state, int field, const char *mode)
static int lookup_container_field(lua_State *state, int field, bool write = false)
{
if (lua_type(state, field) == LUA_TNUMBER)
return field;

lookup_field(state, field, mode);
lookup_field(state, field, write ? "write" : "read");

if (lua_isuserdata(state, -1) && !lua_touserdata(state, -1))
{
if (write)
field_error(state, field, "builtin property", "write");

lua_pop(state, 1);
get_metafield(state);
return 0;
Expand Down Expand Up @@ -783,7 +795,7 @@ static int check_container_index(lua_State *state, int len,
static int meta_container_index(lua_State *state)
{
uint8_t *ptr = get_object_addr(state, 1, 2, "read");
int iidx = lookup_container_field(state, 2, "read");
int iidx = lookup_container_field(state, 2);
if (!iidx)
return 1;

Expand All @@ -800,7 +812,7 @@ static int meta_container_index(lua_State *state)
static int meta_container_newindex(lua_State *state)
{
uint8_t *ptr = get_object_addr(state, 1, 2, "write");
int iidx = lookup_container_field(state, 2, "write");
int iidx = lookup_container_field(state, 2, true);

auto id = (container_identity*)lua_touserdata(state, UPVAL_CONTAINER_ID);
int len = id->lua_item_count(state, ptr);
Expand All @@ -826,7 +838,7 @@ static int meta_bitfield_len(lua_State *state)
static int meta_bitfield_index(lua_State *state)
{
uint8_t *ptr = get_object_addr(state, 1, 2, "read");
int iidx = lookup_container_field(state, 2, "read");
int iidx = lookup_container_field(state, 2);
if (!iidx)
return 1;

Expand Down Expand Up @@ -858,7 +870,7 @@ static int meta_bitfield_index(lua_State *state)
static int meta_bitfield_newindex(lua_State *state)
{
uint8_t *ptr = get_object_addr(state, 1, 2, "write");
int iidx = lookup_container_field(state, 2, "write");
int iidx = lookup_container_field(state, 2, true);

auto id = (bitfield_identity*)lua_touserdata(state, UPVAL_CONTAINER_ID);

Expand Down Expand Up @@ -906,6 +918,8 @@ static int meta_global_index(lua_State *state)
static int meta_global_newindex(lua_State *state)
{
auto field = (struct_field_info*)find_field(state, 2, "write");
if (!field)
field_error(state, 2, "builtin property", "write");
void *ptr = *(void**)field->offset;
if (!ptr)
field_error(state, 2, "global address not known", "write");
Expand All @@ -916,35 +930,24 @@ static int meta_global_newindex(lua_State *state)
/**
* Add fields in the array to the UPVAL_FIELDTABLE candidates on the stack.
*/
static void IndexFields(lua_State *state, const struct_field_info *fields)
static void IndexFields(lua_State *state, struct_identity *pstruct)
{
// stack: read write
// stack: fieldtable

int base = lua_gettop(state) - 2;
int base = lua_gettop(state);

for (; fields; ++fields)
for (struct_identity *p = pstruct; p; p = p->getParent())
{
switch (fields->mode)
{
case struct_field_info::END:
return;
auto fields = p->getFields();

case struct_field_info::PRIMITIVE:
case struct_field_info::STATIC_STRING:
case struct_field_info::POINTER:
lua_pushstring(state,fields->name);
lua_pushlightuserdata(state,(void*)fields);
lua_rawset(state,base+2);
// fallthrough

case struct_field_info::STATIC_ARRAY:
case struct_field_info::SUBSTRUCT:
case struct_field_info::CONTAINER:
case struct_field_info::STL_VECTOR_PTR:
lua_pushstring(state,fields->name);
lua_pushlightuserdata(state,(void*)fields);
lua_rawset(state,base+1);
for (; fields; ++fields)
{
if (fields->mode == struct_field_info::END)
break;

lua_pushstring(state,fields->name);
lua_pushlightuserdata(state,(void*)fields);
lua_rawset(state,base);
}
}
}
Expand Down Expand Up @@ -989,7 +992,7 @@ static void SetStructMethod(lua_State *state, int meta_idx, int ftable_idx,
}

/**
* Make a metatable with most common fields, and two empty tables for UPVAL_FIELDTABLE.
* Make a metatable with most common fields, and an empty table for UPVAL_FIELDTABLE.
*/
static void MakeMetatable(lua_State *state, type_identity *type, const char *kind)
{
Expand All @@ -1005,6 +1008,7 @@ static void MakeMetatable(lua_State *state, type_identity *type, const char *kin
LookupInTable(state, type, DFHACK_TYPEID_TABLE_NAME);
if (lua_isnil(state, -1))
{
// Copy the string from __metatable if no real type
lua_pop(state, 1);
lua_getfield(state, base+1, "__metatable");
}
Expand All @@ -1013,8 +1017,7 @@ static void MakeMetatable(lua_State *state, type_identity *type, const char *kin
lua_pushstring(state, kind);
lua_setfield(state, base+1, "_kind");

lua_newtable(state); // read
lua_newtable(state); // write
lua_newtable(state); // fieldtable
}

/**
Expand All @@ -1025,15 +1028,12 @@ static void MakeFieldMetatable(lua_State *state, struct_identity *pstruct,
{
int base = lua_gettop(state);

MakeMetatable(state, pstruct, "struct"); // meta, read, write
MakeMetatable(state, pstruct, "struct"); // meta, fields

for (struct_identity *p = pstruct; p; p = p->getParent())
{
IndexFields(state, p->getFields());
}
IndexFields(state, pstruct);

SetStructMethod(state, base+1, base+2, reader, "__index");
SetStructMethod(state, base+1, base+3, writer, "__newindex");
SetStructMethod(state, base+1, base+2, writer, "__newindex");

// returns: [metatable readfields writefields];
}
Expand All @@ -1046,13 +1046,13 @@ static void MakePrimitiveMetatable(lua_State *state, type_identity *type)
int base = lua_gettop(state);

MakeMetatable(state, type, "primitive");

SetPtrMethods(state, base+1, base+2);

EnableMetaField(state, base+2, "value", type);
EnableMetaField(state, base+3, "value", type);

SetStructMethod(state, base+1, base+2, meta_primitive_index, "__index");
SetStructMethod(state, base+1, base+3, meta_primitive_newindex, "__newindex");
SetStructMethod(state, base+1, base+2, meta_primitive_newindex, "__newindex");
}

/**
Expand Down Expand Up @@ -1090,9 +1090,7 @@ static void AttachEnumKeys(lua_State *state, int base, type_identity *ienum)
lua_newtable(state);
lua_swap(state);
lua_setfield(state, -2, "__index");
lua_dup(state);
lua_setmetatable(state, base+2);
lua_setmetatable(state, base+3);
}
else
lua_pop(state, 1);
Expand All @@ -1114,6 +1112,7 @@ static void MakeContainerMetatable(lua_State *state, container_identity *type,
MakeMetatable(state, type, "container");
SetPtrMethods(state, base+1, base+2);

// Update the type name using full info
lua_pushstring(state, type->getFullName(item).c_str());
lua_dup(state);
lua_setfield(state, base+1, "__metatable");
Expand All @@ -1130,7 +1129,7 @@ static void MakeContainerMetatable(lua_State *state, container_identity *type,

SetContainerMethod(state, base+1, base+2, meta_container_len, "__len", type, item, count);
SetContainerMethod(state, base+1, base+2, meta_container_index, "__index", type, item, count);
SetContainerMethod(state, base+1, base+3, meta_container_newindex, "__newindex", type, item, count);
SetContainerMethod(state, base+1, base+2, meta_container_newindex, "__newindex", type, item, count);

AttachEnumKeys(state, base, ienum);
}
Expand All @@ -1148,31 +1147,21 @@ void container_identity::build_metatable(lua_State *state)
MakeContainerMetatable(state, this, getItemType(), -1, getIndexEnumType());
}

void pointer_identity::build_metatable(lua_State *state)
{
int base = lua_gettop(state);

primitive_identity::build_metatable(state);

EnableMetaField(state, base+2, "target", this);
EnableMetaField(state, base+3, "target", this);
}

void bitfield_identity::build_metatable(lua_State *state)
{
int base = lua_gettop(state);

MakeMetatable(state, this, "bitfield");

SetPtrMethods(state, base+1, base+2);

SetContainerMethod(state, base+1, base+2, meta_bitfield_len, "__len", this, NULL, -1);
SetContainerMethod(state, base+1, base+2, meta_bitfield_index, "__index", this, NULL, -1);
SetContainerMethod(state, base+1, base+3, meta_bitfield_newindex, "__newindex", this, NULL, -1);
SetContainerMethod(state, base+1, base+2, meta_bitfield_newindex, "__newindex", this, NULL, -1);

AttachEnumKeys(state, base, this);

EnableMetaField(state, base+2, "whole", this);
EnableMetaField(state, base+3, "whole", this);
}

void struct_identity::build_metatable(lua_State *state)
Expand All @@ -1191,7 +1180,7 @@ static void BuildTypeMetatable(lua_State *state, type_identity *type)
{
type->build_metatable(state);

lua_pop(state, 2);
lua_pop(state, 1);

SaveTypeInfo(state, type);
}
Expand Down Expand Up @@ -1229,7 +1218,7 @@ static void GetAdHocMetatable(lua_State *state, const struct_field_info *field)
luaL_error(state, "Invalid ad-hoc field: %d", field->mode);
}

lua_pop(state, 2);
lua_pop(state, 1);

SaveTypeInfo(state, (void*)field);
}
Expand Down Expand Up @@ -1263,9 +1252,6 @@ static void RenderType(lua_State *state, compound_identity *node)

int base = lua_gettop(state);

lua_pushlightuserdata(state, node);
lua_setfield(state, base, "_identity");

switch (node->type())
{
case IDTYPE_STRUCT:
Expand Down Expand Up @@ -1344,12 +1330,14 @@ static void RenderType(lua_State *state, compound_identity *node)
{
BuildTypeMetatable(state, node);

// Set metatable for the inner table
lua_dup(state);
lua_setmetatable(state, base);
lua_swap(state); // -> meta curtable

freeze_table(state, true, "global");

// Copy __newindex to the outer metatable
lua_getfield(state, base, "__newindex");
lua_setfield(state, -2, "__newindex");

Expand All @@ -1363,6 +1351,9 @@ static void RenderType(lua_State *state, compound_identity *node)
lua_getfield(state, LUA_REGISTRYINDEX, DFHACK_TYPE_TOSTRING_NAME);
lua_setfield(state, -2, "__tostring");

lua_pushlightuserdata(state, node);
lua_setfield(state, -2, "_identity");

lua_pop(state, 1);

SaveInTable(state, node, DFHACK_TYPEID_TABLE_NAME);
Expand Down
1 change: 0 additions & 1 deletion library/include/DataIdentity.h
View file
Original file line number Diff line number Diff line change
Expand Up @@ -56,7 +56,6 @@ namespace DFHack
type_identity *getTarget() { return target; }

std::string getFullName();
virtual void build_metatable(lua_State *state);

static void lua_read(lua_State *state, int fname_idx, void *ptr, type_identity *target);
static void lua_write(lua_State *state, int fname_idx, void *ptr, type_identity *target, int val_index);
Expand Down

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