Files
yaze/src/app/core/common.cc
2024-08-31 09:23:17 -04:00

306 lines
8.8 KiB
C++

#include "common.h"
#include <zlib.h>
#include <chrono>
#include <cstdint>
#include <cstring>
#include <fstream>
#include <functional>
#include <iostream>
#include <memory>
#include <stack>
#include <string>
#include <vector>
#include "absl/status/statusor.h"
#include "absl/strings/str_format.h"
#include "app/core/constants.h"
#include "imgui/imgui.h"
namespace yaze {
namespace app {
namespace core {
namespace {
void encode(uint64_t data, std::vector<uint8_t> &output) {
while (true) {
uint8_t x = data & 0x7f;
data >>= 7;
if (data == 0) {
output.push_back(0x80 | x);
break;
}
output.push_back(x);
data--;
}
}
uint64_t decode(const std::vector<uint8_t> &input, size_t &offset) {
uint64_t data = 0;
uint64_t shift = 1;
while (true) {
uint8_t x = input[offset++];
data += (x & 0x7f) * shift;
if (x & 0x80) break;
shift <<= 7;
data += shift;
}
return data;
}
uint32_t crc32(const std::vector<uint8_t> &data) {
uint32_t crc = ::crc32(0L, Z_NULL, 0);
return ::crc32(crc, data.data(), data.size());
}
// "load little endian value at the given byte offset and shift to get its
// value relative to the base offset (powers of 256, essentially)"
unsigned ldle(uint8_t const *const p_arr, unsigned const p_index) {
uint32_t v = p_arr[p_index];
v <<= (8 * p_index);
return v;
}
void stle(uint8_t *const p_arr, size_t const p_index, unsigned const p_val) {
uint8_t v = (p_val >> (8 * p_index)) & 0xff;
p_arr[p_index] = v;
}
void stle0(uint8_t *const p_arr, unsigned const p_val) {
stle(p_arr, 0, p_val);
}
void stle1(uint8_t *const p_arr, unsigned const p_val) {
stle(p_arr, 1, p_val);
}
void stle2(uint8_t *const p_arr, unsigned const p_val) {
stle(p_arr, 2, p_val);
}
void stle3(uint8_t *const p_arr, unsigned const p_val) {
stle(p_arr, 3, p_val);
}
// Helper function to get the first byte in a little endian number
uint32_t ldle0(uint8_t const *const p_arr) { return ldle(p_arr, 0); }
// Helper function to get the second byte in a little endian number
uint32_t ldle1(uint8_t const *const p_arr) { return ldle(p_arr, 1); }
// Helper function to get the third byte in a little endian number
uint32_t ldle2(uint8_t const *const p_arr) { return ldle(p_arr, 2); }
// Helper function to get the third byte in a little endian number
uint32_t ldle3(uint8_t const *const p_arr) { return ldle(p_arr, 3); }
} // namespace
std::shared_ptr<ExperimentFlags::Flags> ExperimentFlags::flags_;
uint32_t Get24LocalFromPC(uint8_t *data, int addr, bool pc) {
uint32_t ret =
(PcToSnes(addr) & 0xFF0000) | (data[addr + 1] << 8) | data[addr];
if (pc) {
return SnesToPc(ret);
}
return ret;
}
void stle16b_i(uint8_t *const p_arr, size_t const p_index,
uint16_t const p_val) {
stle16b(p_arr + (p_index * 2), p_val);
}
void stle16b(uint8_t *const p_arr, uint16_t const p_val) {
stle0(p_arr, p_val);
stle1(p_arr, p_val);
}
uint16_t ldle16b(uint8_t const *const p_arr) {
uint16_t v = 0;
v |= (ldle0(p_arr) | ldle1(p_arr));
return v;
}
uint16_t ldle16b_i(uint8_t const *const p_arr, size_t const p_index) {
return ldle16b(p_arr + (2 * p_index));
}
void CreateBpsPatch(const std::vector<uint8_t> &source,
const std::vector<uint8_t> &target,
std::vector<uint8_t> &patch) {
patch.clear();
patch.insert(patch.end(), {'B', 'P', 'S', '1'});
encode(source.size(), patch);
encode(target.size(), patch);
encode(0, patch); // No metadata
size_t source_offset = 0;
size_t target_offset = 0;
int64_t source_rel_offset = 0;
int64_t target_rel_offset = 0;
while (target_offset < target.size()) {
if (source_offset < source.size() &&
source[source_offset] == target[target_offset]) {
size_t length = 0;
while (source_offset + length < source.size() &&
target_offset + length < target.size() &&
source[source_offset + length] == target[target_offset + length]) {
length++;
}
encode((length - 1) << 2 | 0, patch); // SourceRead
source_offset += length;
target_offset += length;
} else {
size_t length = 0;
while (
target_offset + length < target.size() &&
(source_offset + length >= source.size() ||
source[source_offset + length] != target[target_offset + length])) {
length++;
}
if (length > 0) {
encode((length - 1) << 2 | 1, patch); // TargetRead
for (size_t i = 0; i < length; i++) {
patch.push_back(target[target_offset + i]);
}
target_offset += length;
}
}
// SourceCopy
if (source_offset < source.size()) {
size_t length = 0;
int64_t offset = source_offset - source_rel_offset;
while (source_offset + length < source.size() &&
target_offset + length < target.size() &&
source[source_offset + length] == target[target_offset + length]) {
length++;
}
if (length > 0) {
encode((length - 1) << 2 | 2, patch);
encode((offset < 0 ? 1 : 0) | (abs(offset) << 1), patch);
source_offset += length;
target_offset += length;
source_rel_offset = source_offset;
}
}
// TargetCopy
if (target_offset > 0) {
size_t length = 0;
int64_t offset = target_offset - target_rel_offset;
while (target_offset + length < target.size() &&
target[target_offset - 1] == target[target_offset + length]) {
length++;
}
if (length > 0) {
encode((length - 1) << 2 | 3, patch);
encode((offset < 0 ? 1 : 0) | (abs(offset) << 1), patch);
target_offset += length;
target_rel_offset = target_offset;
}
}
}
patch.resize(patch.size() + 12); // Make space for the checksums
uint32_t source_checksum = crc32(source);
uint32_t target_checksum = crc32(target);
uint32_t patch_checksum = crc32(patch);
memcpy(patch.data() + patch.size() - 12, &source_checksum, sizeof(uint32_t));
memcpy(patch.data() + patch.size() - 8, &target_checksum, sizeof(uint32_t));
memcpy(patch.data() + patch.size() - 4, &patch_checksum, sizeof(uint32_t));
}
void ApplyBpsPatch(const std::vector<uint8_t> &source,
const std::vector<uint8_t> &patch,
std::vector<uint8_t> &target) {
if (patch.size() < 4 || patch[0] != 'B' || patch[1] != 'P' ||
patch[2] != 'S' || patch[3] != '1') {
throw std::runtime_error("Invalid patch format");
}
size_t patch_offset = 4;
uint64_t target_size = decode(patch, patch_offset);
uint64_t metadata_size = decode(patch, patch_offset);
patch_offset += metadata_size;
target.resize(target_size);
size_t source_offset = 0;
size_t target_offset = 0;
int64_t source_rel_offset = 0;
int64_t target_rel_offset = 0;
while (patch_offset < patch.size() - 12) {
uint64_t data = decode(patch, patch_offset);
uint64_t command = data & 3;
uint64_t length = (data >> 2) + 1;
switch (command) {
case 0: // SourceRead
while (length--) {
target[target_offset++] = source[source_offset++];
}
break;
case 1: // TargetRead
while (length--) {
target[target_offset++] = patch[patch_offset++];
}
break;
case 2: // SourceCopy
{
int64_t offsetData = decode(patch, patch_offset);
source_rel_offset += (offsetData & 1 ? -1 : +1) * (offsetData >> 1);
while (length--) {
target[target_offset++] = source[source_rel_offset++];
}
} break;
case 3: // TargetCopy
{
uint64_t offsetData = decode(patch, patch_offset);
target_rel_offset += (offsetData & 1 ? -1 : +1) * (offsetData >> 1);
while (length--) {
target[target_offset++] = target[target_rel_offset++];
}
}
default:
throw std::runtime_error("Invalid patch command");
}
}
uint32_t source_checksum;
uint32_t target_checksum;
uint32_t patch_checksum;
memcpy(&source_checksum, patch.data() + patch.size() - 12, sizeof(uint32_t));
memcpy(&target_checksum, patch.data() + patch.size() - 8, sizeof(uint32_t));
memcpy(&patch_checksum, patch.data() + patch.size() - 4, sizeof(uint32_t));
if (source_checksum != crc32(source) || target_checksum != crc32(target) ||
patch_checksum !=
crc32(std::vector<uint8_t>(patch.begin(), patch.end() - 4))) {
throw std::runtime_error("Checksum mismatch");
}
}
absl::StatusOr<std::string> CheckVersion(const char *version) {
std::string version_string = version;
if (version_string != kYazeVersion) {
std::string message =
absl::StrFormat("Yaze version mismatch: expected %s, got %s",
kYazeVersion.data(), version_string.c_str());
return absl::InvalidArgumentError(message);
}
return version_string;
}
} // namespace core
} // namespace app
} // namespace yaze