Given at !!con West 2019

1. @stillinbeta ; #bangbangconwest
Postgres!
Plays!
!

2. @stillinbeta ; #bangbangconwest
Hello There!
Welcome to the world of Pokemon!

3. @stillinbeta ; #bangbangconwest
Me?

4. @stillinbeta ; #bangbangconwest
I am a queer

5. @stillinbeta ; #bangbangconwest
trans...

6. @stillinbeta ; #bangbangconwest
polyamorous

7. @stillinbeta ; #bangbangconwest
Programmer

8. @stillinbeta ; #bangbangconwest
(and sometimes pony)

9. @stillinbeta ; #bangbangconwest
At Recurse!

10. @stillinbeta ; #bangbangconwest
Pokemon Red

11. @stillinbeta ; #bangbangconwest
● Released in Japan in 1996
● Greyscale
● Fits into 1 mb of space
Pokemon 101

12. @stillinbeta ; #bangbangconwest
The Game Boy

13. @stillinbeta ; #bangbangconwest
● Released in 1989
Original Gameboy

14. @stillinbeta ; #bangbangconwest
● Released in 1989
● Modified Z80, 4.91 Mhz
Original Gameboy

15. @stillinbeta ; #bangbangconwest
● Released in 1989
● Modified Z80, 4.91 Mhz
● 8 kiB internal S-RAM
Original Gameboy

16. @stillinbeta ; #bangbangconwest
● Released in 1989
● Modified Z80, 4.91 Mhz
● 8 kiB internal S-RAM
● 160 × 144 pixels
Original Gameboy

17. @stillinbeta ; #bangbangconwest

18. @stillinbeta ; #bangbangconwest
● Use MissingNo Glitch
How does it work!?

19. @stillinbeta ; #bangbangconwest
● Use MissingNo Glitch
● Get Code Execution
How does it work!?

20. @stillinbeta ; #bangbangconwest
● Use MissingNo Glitch
● Get Code Execution
● Live-Patch Assembly Code
How does it work!?

21. @stillinbeta ; #bangbangconwest
● Use MissingNo Glitch
● Get Code Execution
● Live-Patch Assembly Code
● Listen on Link Port
How does it work!?

22. @stillinbeta ; #bangbangconwest
● Use MissingNo Glitch
● Get Code Execution
● Live-Patch Assembly Code
● Listen on Link Port
● Modify Memory
How does it work!?

23. @stillinbeta ; #bangbangconwest
● Use MissingNo Glitch
● Get Code Execution
● Live-Patch Assembly Code
● Listen on Link Port
● Modify Memory!
How does it work!?
● getMemoryValue(address)
● setMemoryValue(address, value)

24. @stillinbeta ; #bangbangconwest
Architecture

25. @stillinbeta ; #bangbangconwest
I made this!

26. @stillinbeta ; #bangbangconwest
Architecture

27. @stillinbeta ; #bangbangconwest
PyBoy

28. @stillinbeta ; #bangbangconwest
PyBoy

29. @stillinbeta ; #bangbangconwest
PyBoy
● Python 2.7
● Actually PyPy
● 180MB Memory
● SDL2 (Segfaults!)
● Doesn’t work on my
Chromebook

30. @stillinbeta ; #bangbangconwest
service PokemonRed {
rpc GetPokemon (GetPokemonRequest) returns (Party) {}
rpc UpdatePokemon (UpdatePokemonRequest) returns (UpdatePokemonResponse) {}
rpc GetInventory(GetInventoryRequest) returns (GetInventoryResponse) {}
rpc UpdateInventory(UpdateInventoryRequest) returns (UpdateInventoryResponse) {}
rpc AddItem(AddItemRequest) returns (AddItemResponse) {}
rpc GetEvents(GetEventsRequest) returns (GetEventsResponse) {}
rpc SetEvent(SetEventRequest) returns (SetEventResponse) {}
rpc SetMemory (MemoryUpdate) returns (MemoryResponse) {}
}

31. @stillinbeta ; #bangbangconwest
service PokemonRed {
rpc GetPokemon (GetPokemonRequest) returns (Party) {}
rpc UpdatePokemon (UpdatePokemonRequest) returns (UpdatePokemonResponse) {}
rpc GetInventory(GetInventoryRequest) returns (GetInventoryResponse) {}
rpc UpdateInventory(UpdateInventoryRequest) returns (UpdateInventoryResponse) {}
rpc AddItem(AddItemRequest) returns (AddItemResponse) {}
rpc GetEvents(GetEventsRequest) returns (GetEventsResponse) {}
rpc SetEvent(SetEventRequest) returns (SetEventResponse) {}
rpc SetMemory (MemoryUpdate) returns (MemoryResponse) {}
}

32. @stillinbeta ; #bangbangconwest
Why Pokemon?
Why Red?!

33. @stillinbeta ; #bangbangconwest
We have the map!

34. @stillinbeta ; #bangbangconwest
0x00 Index # of the Species 1 byte
0x01 Current HP 2 bytes
0x03 Level 1 byte
0x04 Status condition 1 byte
0x05 Type 1 1 byte
0x06 Type 2 1 byte
0x07 Catch rate/Held item 1 byte
0x08 Index number of move 1 1 byte
0x09 Index number of move 2 1 byte
0x0A Index number of move 3 1 byte
0x0B Index number of move 4 1 byte
0x0C Original Trainer ID number 2 bytes
0x0E Experience points 3 bytes
0x11 HP EV data 2 bytes
0x13 Attack EV data 2 bytes
0x15 Defense EV data 2 bytes
0x17 Speed EV data 2 bytes
0x19 Special EV data 2 bytes
0x1B IV data 2 bytes
0x1D Move 1's PP values 1 byte
0x1E Move 2's PP values 1 byte
0x1F Move 3's PP values 1 byte
0x20 Move 4's PP values 1 byte
0x21 Level 1 byte
0x22 Maximum HP 2 bytes
0x24 Attack 2 bytes
0x26 Defense 2 bytes
0x28 Speed 2 bytes
0x2A Special 2 bytes

35. @stillinbeta ; #bangbangconwest
0x00 Index # of the Species 1 byte
0x01 Current HP 2 bytes
0x03 Level 1 byte
0x04 Status condition 1 byte
0x05 Type 1 1 byte
0x06 Type 2 1 byte
0x07 Catch rate/Held item 1 byte
0x08 Index number of move 1 1 byte
0x09 Index number of move 2 1 byte
0x0A Index number of move 3 1 byte
0x0B Index number of move 4 1 byte
0x0C Original Trainer ID number 2 bytes
0x0E Experience points 3 bytes
0x11 HP EV data 2 bytes
0x13 Attack EV data 2 bytes
0x15 Defense EV data 2 bytes
0x17 Speed EV data 2 bytes
0x19 Special EV data 2 bytes
0x1B IV data 2 bytes
0x1D Move 1's PP values 1 byte
0x1E Move 2's PP values 1 byte
0x1F Move 3's PP values 1 byte
0x20 Move 4's PP values 1 byte
0x21 Level 1 byte
0x22 Maximum HP 2 bytes
0x24 Attack 2 bytes
0x26 Defense 2 bytes
0x28 Speed 2 bytes
0x2A Special 2 bytes

36. @stillinbeta ; #bangbangconwest
message GetPokemonRequest {} message Pokemon {
uint32 id = 1;
uint32 hp = 2;
uint32 level = 3;
uint32 max_hp = 4;
uint32 attack = 5;
uint32 defense = 6;
uint32 speed = 7;
uint32 special = 8;
uint32 position = 99;
}
message Party {
repeated Pokemon party = 1;
}

37. @stillinbeta ; #bangbangconwest
D163 - # Pokémon In Party
D164 - Pokémon ID 1
D165 - Pokémon ID 2
D166 - Pokémon ID 3
D167 - Pokémon ID 4
D168 - Pokémon ID 5
D169 - Pokémon ID 6
D16A - End of list
D16B - Pokémon 1
D197 - Pokémon 2
D1C3 - Pokémon 3
D1EF - Pokémon 4
D21B - Pokémon 5
D247 - Pokémon

38. @stillinbeta ; #bangbangconwest
pokemon = self.get_pokemon(
POKEMON_PARTY_START
+ POKEMON_STRUCT_SIZE * i)

39. @stillinbeta ; #bangbangconwest
def get_pokemon(self, offset):
return pb.Pokemon(
id=self._pyboy.getMemoryValue(offset),
hp=_get_two_bytes(self._pyboy, offset + 0x1),
level=self._pyboy.getMemoryValue(offset + 0x3),
max_hp=_get_two_bytes(self._pyboy, offset + 0x22),
attack=_get_two_bytes(self._pyboy, offset + 0x24),
defense=_get_two_bytes(self._pyboy, offset + 0x26),
speed=_get_two_bytes(self._pyboy, offset + 0x28),
special=_get_two_bytes(self._pyboy, offset + 0x2A),
)

40. @stillinbeta ; #bangbangconwest
# Values are big-endian
def _get_two_bytes(pyboy, address):
return (pyboy.getMemoryValue(address) << 8) +
pyboy.getMemoryValue(address + 0x1))

41. @stillinbeta ; #bangbangconwest
What about
Postgres?!

42. @stillinbeta ; #bangbangconwest
Architecture

43. @stillinbeta ; #bangbangconwest
Postgres
extensions!

44. @stillinbeta ; #bangbangconwest
#include "postgres.h"
#include "executor/executor.h" /* for GetAttributeByName() */
#ifdef PG_MODULE_MAGIC
PG_MODULE_MAGIC;
#endif
PG_FUNCTION_INFO_V1(c_overpaid);
Datum
c_overpaid(PG_FUNCTION_ARGS)
{
HeapTupleHeader t = PG_GETARG_HEAPTUPLEHEADER(0);
int32 limit = PG_GETARG_INT32(1);
bool isnull;
Datum salary;
salary = GetAttributeByName(t, "salary", &isnull);
if (isnull)
PG_RETURN_BOOL(false);
PG_RETURN_BOOL(DatumGetInt32(salary) > limit);
}

45. @stillinbeta ; #bangbangconwest
CREATE FUNCTION c_overpaid(emp, integer) RETURNS boolean
AS 'DIRECTORY/funcs', 'c_overpaid'
LANGUAGE C STRICT;

46. @stillinbeta ; #bangbangconwest
CREATE FUNCTION c_overpaid(emp, integer) RETURNS boolean
AS 'DIRECTORY/funcs', 'c_overpaid'
LANGUAGE C STRICT;

47. @stillinbeta ; #bangbangconwest
“C” is more of
a... suggestion

48. @stillinbeta ; #bangbangconwest
github.com/bluejekyll/pg-extend-rs

49. @stillinbeta ; #bangbangconwest
/// This tells Postgres this library is a Postgres extension
pg_magic!(version: pg_sys::PG_VERSION_NUM);
/// The pg_extern attribute wraps the function in the proper
functions syntax for C extensions
#[pg_extern]
fn add_one(value: i32) -> i32 {
(value + 1)
}

50. @stillinbeta ; #bangbangconwest
Foreign Data
Wrappers

51. @stillinbeta ; #bangbangconwest
Foreign Function:Values
Foreign Data Wrapper:Tables

52. @stillinbeta ; #bangbangconwest
void
BeginForeignScan(
ForeignScanState *node,
int eflags);
TupleTableSlot *
IterateForeignScan(
ForeignScanState *node);

53. @stillinbeta ; #bangbangconwest
fn begin(_sopts: OptionMap, _topts: OptionMap, _table_name: String) -> Self {
DefaultFDW {i: 0}
}
fn next(&mut self) -> Option<Self::Item> {
self.i += 1;
if self.i > 5 {
None
} else {
Some(Box::new(MyRow{i: self.i}))
}
}
}

54. @stillinbeta ; #bangbangconwest
Back to Pallet town...

55. @stillinbeta ; #bangbangconwest
.addNewItem ; add an item not yet in the inventory
pop hl
ld a, d
and a ; is there room for a new item slot?
jr z, .done
; if there is room
inc [hl] ; increment the number of items in the inventory
ld a, [hl] ; the number of items will be the index of the new item
add a
dec a
ld c, a
ld b, 0
add hl, bc ; hl = address to store the item
ld a, [wcf91]
ld [hli], a ; store item ID
ld a, [wItemQuantity]
ld [hli], a ; store item quantity
ld [hl], $ff ; store terminator
jp .success

56. @stillinbeta ; #bangbangconwest
.addNewItem ; add an item not yet in the inventory
pop hl ; pop stack into accumulator
ld a, d ; move a from d
and a ; is there room for a new item slot?
jr z, .done
; if there is room
inc [hl] ; increment the number of items in the inventory
ld a, [hl] ; the number of items will be the index of the new item
add a ; double accumulator
dec a ; subtract one
ld c, a ; move accumulator to 0
ld b, 0 ; put 0
add hl, bc ; # of items * 2 - 1 + location of index
ld a, [wcf91] ; move item ID to a
ld [hli], a ; store item ID
ld a, [wItemQuantity] ; move item quantity to a
ld [hli], a ; store item quantity
ld [hl], $ff ; store terminator in next slot
jp .success

57. @stillinbeta ; #bangbangconwest
.addNewItem ; add an item not yet in the inventory
pop hl ; pop stack into accumulator
ld a, d ; move a from d
and a ; is there room for a new item slot?
jr z, .done
; if there is room
inc [hl] ; increment the number of items in the inventory
ld a, [hl] ; the number of items will be the index of the new item
add a ; double accumulator
dec a ; subtract one
ld c, a ; move accumulator to 0
ld b, 0 ; put 0
add hl, bc ; # of items * 2 - 1 + location of index
ld a, [wcf91] ; move item ID to a
ld [hli], a ; store item ID
ld a, [wItemQuantity] ; move item quantity to a
ld [hli], a ; store item quantity
ld [hl], $ff ; store terminator in next slot
jp .success

58. @stillinbeta ; #bangbangconwest
ld [hl], $ff ; store terminator in next
slot
jp .success

59. @stillinbeta ; #bangbangconwest
Special Thanks
Benjamin Fry (pg-extend-rs)
Mads Ynddal (PyBoy)
Natalie Wolek (knowing everything about Pokemon)

60. @stillinbeta ; #bangbangconwest
@stillinbeta
gayhorse.club/@beta
github.com/stillinbeta/PostgresPlaysPokemon