sc: bone eater preliminary support (#895)

## Link to GitHub Issue or related Pull Request, if one exists
Fixes #114

## Description of change
Initial support for Silent Scope: Bone Eater, enough to be playable;
doesn't include QoS work needed to make this a smoother experience.

* Game detection
* Fix DX11 overlay to work with non-Unity games
* Implements sub monitor i/o (only really needed to get past I/O check)
* Try to make the game reasonably playable with a mouse
* Ignore the game's attempt to move windows, position them in a
reasonable place
* Fix language hook

## Testing

src/spice2x/games/silentscope/projector.cpp

@@ -0,0 +1,150 @@
+#include "projector.h"
+
+#include <algorithm>
+#include <cstring>
+#include <cwchar>
+
+#include "util/logging.h"
+
+namespace {
+
+    // request/response layout: identifier, command, two zero bytes, payload length,
+    // the payload itself and a checksum over everything before it
+    constexpr size_t HEADER_SIZE = 5;
+    constexpr uint8_t RESPONSE_ID = 0x23;
+
+    constexpr uint8_t COMMAND_COMMON_DATA = 0x8A;
+    constexpr uint8_t COMMAND_TEMPERATURE = 0x99;
+    constexpr uint8_t COMMAND_LAMP_CURRENT = 0x9B;
+
+    // shown in the test menu as PROJTIM, PROJHEATIN and PROJHEAT
+    constexpr uint32_t LAMP_SECONDS = 0;
+    constexpr uint32_t TEMPERATURE_INTAKE = 25;
+    constexpr uint32_t TEMPERATURE_EXHAUST = 35;
+
+    // anything below 1000 is treated as a lamp anomaly and raises PROJERROR unless the exact
+    // value was already recorded in /projecter/current on an earlier boot
+    constexpr uint32_t LAMP_CURRENT = 1000;
+
+    void put32(uint8_t *dest, uint32_t value) {
+        dest[0] = (uint8_t) (value & 0xFF);
+        dest[1] = (uint8_t) ((value >> 8) & 0xFF);
+        dest[2] = (uint8_t) ((value >> 16) & 0xFF);
+        dest[3] = (uint8_t) ((value >> 24) & 0xFF);
+    }
+}
+
+bool games::silentscope::ProjectorHandle::open(LPCWSTR lpFileName) {
+    if (wcscmp(lpFileName, L"COM2") != 0 && wcscmp(lpFileName, L"\\\\.\\COM2") != 0) {
+        return false;
+    }
+
+    log_info("silentscope", "Opened COM2 (projector)");
+
+    return true;
+}
+
+int games::silentscope::ProjectorHandle::read(LPVOID lpBuffer, DWORD nNumberOfBytesToRead) {
+    std::lock_guard<std::mutex> lock(this->mutex);
+
+    auto buffer = reinterpret_cast<uint8_t *>(lpBuffer);
+
+    DWORD bytes_read = 0;
+    while (bytes_read < nNumberOfBytesToRead && !this->response.empty()) {
+        buffer[bytes_read++] = this->response.front();
+        this->response.pop_front();
+    }
+
+    return (int) bytes_read;
+}
+
+int games::silentscope::ProjectorHandle::write(LPCVOID lpBuffer, DWORD nNumberOfBytesToWrite) {
+    std::lock_guard<std::mutex> lock(this->mutex);
+
+    auto buffer = reinterpret_cast<const uint8_t *>(lpBuffer);
+    this->request.insert(this->request.end(), buffer, buffer + nNumberOfBytesToWrite);
+
+    while (this->request.size() >= HEADER_SIZE) {
+        const size_t packet_size = HEADER_SIZE + this->request[4] + 1;
+        if (this->request.size() < packet_size) {
+            break;
+        }
+
+        this->process_request(this->request.data());
+        this->request.erase(this->request.begin(), this->request.begin() + packet_size);
+    }
+
+    return (int) nNumberOfBytesToWrite;
+}
+
+size_t games::silentscope::ProjectorHandle::bytes_available() {
+    std::lock_guard<std::mutex> lock(this->mutex);
+
+    return this->response.size();
+}
+
+bool games::silentscope::ProjectorHandle::close() {
+    std::lock_guard<std::mutex> lock(this->mutex);
+
+    this->request.clear();
+    this->response.clear();
+
+    log_info("silentscope", "Closed COM2 (projector)");
+
+    return true;
+}
+
+void games::silentscope::ProjectorHandle::process_request(const uint8_t *packet) {
+    const uint8_t command = packet[1];
+    const uint8_t length = packet[4];
+    const uint8_t *data = packet + HEADER_SIZE;
+
+    switch (command) {
+        case COMMAND_COMMON_DATA: {
+
+            // the game only looks at the lamp usage time near the end of the block
+            std::vector<uint8_t> payload(98, 0);
+            put32(&payload[94], LAMP_SECONDS);
+            this->reply(command, payload);
+            break;
+        }
+        case COMMAND_TEMPERATURE: {
+
+            // the requested sensor is echoed back along with its reading
+            const uint8_t sensor = length > 0 ? data[0] : 0;
+            std::vector<uint8_t> payload(5, 0);
+            payload[0] = sensor;
+            put32(&payload[1], sensor == 0 ? TEMPERATURE_INTAKE : TEMPERATURE_EXHAUST);
+            this->reply(command, payload);
+            break;
+        }
+        case COMMAND_LAMP_CURRENT: {
+
+            // the three byte item selector is echoed back along with the measurement
+            std::vector<uint8_t> payload(7, 0);
+            memcpy(payload.data(), data, std::min<size_t>(length, 3));
+            put32(&payload[3], LAMP_CURRENT);
+            this->reply(command, payload);
+            break;
+        }
+        default:
+            log_misc("silentscope", "unknown projector command {:#04x}", command);
+            this->reply(command, {});
+            break;
+    }
+}
+
+void games::silentscope::ProjectorHandle::reply(uint8_t command, const std::vector<uint8_t> &data) {
+    std::vector<uint8_t> packet {
+        RESPONSE_ID, command, 0x00, 0x00, (uint8_t) data.size()
+    };
+    packet.insert(packet.end(), data.begin(), data.end());
+
+    uint8_t checksum = 0;
+    for (auto byte : packet) {
+        checksum += byte;
+    }
+    packet.push_back(checksum);
+
+    this->response.insert(this->response.end(), packet.begin(), packet.end());
+}

src/spice2x/games/silentscope/projector.h

@@ -0,0 +1,30 @@
+#pragma once
+
+#include <cstdint>
+#include <deque>
+#include <mutex>
+#include <vector>
+
+#include "hooks/devicehook.h"
+
+namespace games::silentscope {
+
+    // The cabinet talks to its projector over COM2. Without an answer the game stops at
+    // I/O error 5-1560-0004 (IOCOM2, "the projector is not connected correctly").
+    class ProjectorHandle : public CustomHandle {
+    public:
+        bool open(LPCWSTR lpFileName) override;
+        int read(LPVOID lpBuffer, DWORD nNumberOfBytesToRead) override;
+        int write(LPCVOID lpBuffer, DWORD nNumberOfBytesToWrite) override;
+        size_t bytes_available() override;
+        bool close() override;
+
+    private:
+        std::mutex mutex;
+        std::vector<uint8_t> request;
+        std::deque<uint8_t> response;
+
+        void process_request(const uint8_t *packet);
+        void reply(uint8_t command, const std::vector<uint8_t> &data);
+    };
+}

src/spice2x/games/silentscope/silentscope.cpp

@@ -1,10 +1,11 @@
 #include "silentscope.h"
 
-#include "acioemu/handle.h"
 #include "cfg/configurator.h"
 #include "hooks/devicehook.h"
 #include "util/libutils.h"
 
+#include "projector.h"
+
 namespace games::silentscope {
 
     SilentScopeGame::SilentScopeGame() : Game("Silent Scope") {
@@ -16,9 +17,8 @@ namespace games::silentscope {
         // load the game DLL so hooks apply
         libutils::try_library("gamendd.dll");
 
-        // TODO(felix): implement stuff on this port
         devicehook_init();
-        devicehook_add(new acioemu::ACIOHandle(L"COM2"));
+        devicehook_add(new ProjectorHandle());
     }
 
     void SilentScopeGame::detach() {