add '--log' command line parameter

src/engine/CoreParameters.hpp

@@ -12,6 +12,7 @@ struct CoreParameters {
     std::filesystem::path userFolder = ".";
     std::filesystem::path scriptFile;
     std::filesystem::path projectFolder;
+    std::filesystem::path logFile;
     std::string debugServerString;
     int tps = 20;
     int subProcessDepth = 0;

src/main.cpp

@@ -7,6 +7,7 @@
 #include <iostream>
 #include <stdexcept>
 
+using namespace std::literals;
 static debug::Logger logger("main");
 
 static void sigterm_handler(int signum) {
@@ -36,7 +37,14 @@ int main(int argc, char** argv) {
 #ifdef NDEBUG
     std::signal(SIGINT, sigterm_handler);
 #endif
-    debug::Logger::init(coreParameters.userFolder.string() + "/latest.log");
+    std::filesystem::path logFile = coreParameters.logFile;
+    if (logFile.empty()) {
+        logFile = coreParameters.userFolder.string() + "/latest"s +
+                  (coreParameters.subProcessDepth > 0
+                       ? ".sub" + std::to_string(coreParameters.subProcessDepth)
+                       : "") + ".log"s;
+    }
+    debug::Logger::init(logFile);
     platform::configure_encoding();
 
     auto& engine = Engine::getInstance();

src/util/command_line.cpp

@@ -82,6 +82,10 @@ static bool perform_keyword(
             params.subProcessDepth = reader.nextInt();
             return true;
         }, "<depth>", "sub-process depth"),
+        ArgC("--log", [](auto& params, auto& reader) -> bool {
+            params.logFile = reader.next();
+            return true;
+        }, "<file>", "target log file"),
         ArgC("--help", [](auto&, auto&) -> bool {
             std::cout << "VoxelCore v" << ENGINE_VERSION_STRING << "\n\n";
             std::cout << "Command-line arguments:\n";