Merge pull request #911 from MihailRis/log-param

--log command line argument

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/logic/scripting/lua/libs/libapp.cpp

@@ -403,6 +403,7 @@ static int l_start_background_instance(lua::State* L) {
         "--script", io::resolve(scriptPath).u8string(),
         "--sub-depth", std::to_string(engine->getCoreParameters()
             .subProcessDepth + 1),
+        "--log", io::resolve(outputPath).u8string(),
     };
     args.emplace_back("--project");
     args.emplace_back(io::resolve(engine->getProject().path).u8string());
@@ -417,11 +418,9 @@ static int l_start_background_instance(lua::State* L) {
     if (handle == -1) {
         throw std::runtime_error("sub-processes limit exceeded");
     }
-    ::processes[handle] = platform::new_engine_instance(
-        std::move(args),
-        outputPath.empty() ? "" : io::resolve(outputPath),
-        true 
-    );
+    ::processes[handle] =
+        platform::new_engine_instance(std::move(args), "", true);
+
     return lua::pushinteger(L, handle);
 }
 

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.u8string());
     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";

src/util/platform.cpp

@@ -28,6 +28,8 @@
     #include <sys/wait.h>
 #endif
 
+using namespace std::literals;
+
 namespace platform::internal {
     std::filesystem::path get_executable_path();
 }
@@ -356,7 +358,7 @@ std::unique_ptr<Process> platform::new_engine_instance(
     if (!outputFile.empty()) {
         si.dwFlags |= STARTF_USESTDHANDLES;
         si.hStdOutput = CreateFileW(
-            toWString(outputFile.u8string()).data(),
+            toWString(outputFile.empty() ? outputFile.u8string() : "NUL"s).data(),
             GENERIC_WRITE,
             FILE_SHARE_WRITE | FILE_SHARE_READ,
             nullptr,
@@ -434,9 +436,12 @@ std::unique_ptr<Process> platform::new_engine_instance(
     if (subProcess) {
         pid_t pid = fork();
 
+        if (outputFile.empty()) {
+            outputFile = "/dev/null";
+        }
         int fd = open(
             outputFile.string().c_str(), O_WRONLY | O_CREAT | O_TRUNC, 0644
-        );
+        ); 
 
         if (pid == 0) {
             prctl(PR_SET_PDEATHSIG, SIGTERM);