Added CLI argument for user-path (#148)

Simple addition to the CLI args. It could probably do with some
validation, ie; making sure it ends in a slash.

cc: @WiserTixx

src/GameStart.cpp

@@ -18,47 +18,86 @@
 #endif
 
 #include "Logger.h"
+#include "Options.h"
 #include "Startup.h"
+#include "Utils.h"
 #include <Security/Init.h>
 #include <filesystem>
 #include <thread>
-#include "Options.h"
+
+#include <fstream>
 
 unsigned long GamePID = 0;
 #if defined(_WIN32)
 std::string QueryKey(HKEY hKey, int ID);
 std::string GetGamePath() {
-    static std::string Path;
+    static std::filesystem::path Path;
     if (!Path.empty())
-        return Path;
+        return Path.string();
 
-    HKEY hKey;
-    LPCTSTR sk = "Software\\BeamNG\\BeamNG.drive";
-    LONG openRes = RegOpenKeyEx(HKEY_CURRENT_USER, sk, 0, KEY_ALL_ACCESS, &hKey);
-    if (openRes != ERROR_SUCCESS) {
-        fatal("Please launch the game at least once!");
+    if (options.user_path) {
+        if (std::filesystem::exists(options.user_path)) {
+            Path = options.user_path;
+            debug("Using custom user folder path: " + Path.string());
+        } else
+            warn("Invalid or non-existent path (" + std::string(options.user_path) + ") specified using --user-path, skipping");
     }
-    Path = QueryKey(hKey, 4);
 
-    if (Path.empty()) {
-        Path = "";
-        char appDataPath[MAX_PATH];
-        HRESULT result = SHGetFolderPathA(NULL, CSIDL_LOCAL_APPDATA, NULL, 0, appDataPath);
-        if (SUCCEEDED(result)) {
-            Path = appDataPath;
+    if (const auto startupIniPath = std::filesystem::path(GetGameDir()) / "startup.ini"; exists(startupIniPath)) {
+
+        if (std::ifstream startupIni(startupIniPath); startupIni.is_open()) {
+            std::string contents((std::istreambuf_iterator(startupIni)), std::istreambuf_iterator<char>());
+            startupIni.close();
+
+            if (contents.size() > 3) {
+                contents.erase(0, 3);
+            }
+
+            auto ini = Utils::ParseINI(contents);
+                if (ini.empty()) {
+                    warn("Failed to parse startup.ini");
+                } else
+                    debug("Successfully parsed startup.ini");
+
+
+                std::string userPath;
+                if (ini.contains("filesystem") && ini["filesystem"].contains("UserPath"))
+                    userPath = ini["filesystem"]["UserPath"];
+
+                if (!userPath.empty())
+                    if (userPath = Utils::ExpandEnvVars(userPath); std::filesystem::exists(userPath)) {
+                        Path = userPath;
+                        debug("Using custom user folder path from startup.ini: " + Path.string());
+                    } else
+                        warn("Found custom user folder path ("+ userPath + ") in startup.ini but it doesn't exist, skipping");
         }
 
         if (Path.empty()) {
-            fatal("Cannot get Local Appdata directory");
-        }
+            HKEY hKey;
+            LPCTSTR sk = "Software\\BeamNG\\BeamNG.drive";
+            LONG openRes = RegOpenKeyEx(HKEY_CURRENT_USER, sk, 0, KEY_ALL_ACCESS, &hKey);
+            if (openRes != ERROR_SUCCESS) {
+                fatal("Please launch the game at least once!");
+            }
+            Path = QueryKey(hKey, 4);
 
-        Path += "\\BeamNG.drive\\";
+            if (Path.empty()) {
+                char appDataPath[MAX_PATH];
+                HRESULT result = SHGetFolderPathA(NULL, CSIDL_LOCAL_APPDATA, NULL, 0, appDataPath);
+
+                if (!SUCCEEDED(result)) {
+                    fatal("Cannot get Local Appdata directory");
+                }
+
+                Path = std::filesystem::path(appDataPath) / "BeamNG.drive";
+            }
+        }
     }
 
     std::string Ver = CheckVer(GetGameDir());
     Ver = Ver.substr(0, Ver.find('.', Ver.find('.') + 1));
-    Path += Ver + "\\";
-    return Path;
+    Path = Path / (Ver + "\\");
+    return Path.string();
 }
 #elif defined(__linux__)
 std::string GetGamePath() {

src/Options.cpp

@@ -86,6 +86,12 @@ void InitOptions(int argc, const char *argv[], Options &options) {
             options.no_download = true;
             options.no_launch = true;
             options.no_update = true;
+        } else if (argument == "--user-path") {
+            if (i + 1 >= argc) {
+                error("You must specify a path after the `--user-path` argument");
+            }
+            options.user_path = argv[i + 1];
+            i++;
         } else if (argument == "--" || argument == "--game") {
             options.game_arguments = &argv[i + 1];
             options.game_arguments_length = argc - i - 1;
@@ -101,6 +107,7 @@ void InitOptions(int argc, const char *argv[], Options &options) {
                 "\t--no-update          Skip applying launcher updates (you must update manually)\n"
                 "\t--no-launch          Skip launching the game (you must launch the game manually)\n"
                 "\t--dev                Developer mode, same as --verbose --no-download --no-launch --no-update\n"
+                "\t--user-path <path>   Path to BeamNG's User Path\n"
                 "\t--game <args...>     Passes ALL following arguments to the game, see also `--`\n"
                 << std::flush;
             exit(0);