Add config class for loading and saving of config file

src/xenia/config.cc

@@ -0,0 +1,126 @@
+#include "config.h"
+#include "cpptoml/include/cpptoml.h"
+#include "xenia/base/cvar.h"
+#include "xenia/base/filesystem.h"
+#include "xenia/base/logging.h"
+#include "xenia/base/string.h"
+
+CmdVar(config, "", "Specifies the target config to load.");
+namespace config {
+std::wstring config_name = L"xenia.config.toml";
+std::wstring config_folder;
+std::wstring config_path;
+
+bool sortCvar(cvar::IConfigVar* a, cvar::IConfigVar* b) {
+  if (a->GetCategory() < b->GetCategory()) return true;
+  if (a->GetCategory() > b->GetCategory()) return false;
+  if (a->GetName() < b->GetName()) return true;
+  return false;
+}
+
+std::shared_ptr<cpptoml::table> ParseConfig(std::string config_path) {
+  try {
+    return cpptoml::parse_file(config_path);
+  } catch (cpptoml::parse_exception) {
+    xe::FatalError("Failed to parse config file: %s", config_path.c_str());
+    return nullptr;
+  }
+}
+
+void ReadConfig(const std::wstring& file_path) {
+  const auto config = ParseConfig(xe::to_string(file_path));
+  for (auto& it : *cvar::ConfigVars) {
+    auto configVar = static_cast<cvar::IConfigVar*>(it.second);
+    auto configKey = configVar->GetCategory() + "." + configVar->GetName();
+    if (config->contains_qualified(configKey)) {
+      configVar->LoadConfigValue(config->get_qualified(configKey));
+    }
+  }
+  XELOGI("Loaded config: %S", file_path.c_str());
+}
+
+void ReadGameConfig(std::wstring file_path) {
+  const auto config = ParseConfig(xe::to_string(file_path));
+  for (auto& it : *cvar::ConfigVars) {
+    auto configVar = static_cast<cvar::IConfigVar*>(it.second);
+    auto configKey = configVar->GetCategory() + "." + configVar->GetName();
+    if (config->contains_qualified(configKey)) {
+      configVar->LoadGameConfigValue(config->get_qualified(configKey));
+    }
+  }
+  XELOGI("Loaded game config: %S", file_path.c_str());
+}
+
+void SaveConfig() {
+  std::vector<cvar::IConfigVar*> vars;
+  for (const auto& s : *cvar::ConfigVars) vars.push_back(s.second);
+  std::sort(vars.begin(), vars.end(), sortCvar);
+  // we use our own write logic because cpptoml doesn't
+  // allow us to specify comments :(
+  std::ostringstream output;
+  std::string lastCategory;
+  for (auto configVar : vars) {
+    if (lastCategory != configVar->GetCategory()) {
+      if (!lastCategory.empty()) {
+        output << std::endl;
+      }
+      lastCategory = configVar->GetCategory();
+      output << xe::format_string("[%s]\n", lastCategory.c_str());
+    }
+    output << std::left << std::setw(40) << std::setfill(' ')
+           << xe::format_string("%s = %s", configVar->GetName().c_str(),
+                                configVar->GetConfigValue().c_str());
+    output << xe::format_string("\t# %s\n",
+                                configVar->GetDescription().c_str());
+  }
+
+  if (xe::filesystem::PathExists(config_path)) {
+    std::ifstream existingConfigStream(xe::to_string(config_path).c_str());
+    const std::string existingConfig(
+        (std::istreambuf_iterator<char>(existingConfigStream)),
+        std::istreambuf_iterator<char>());
+    // if the config didn't change, no need to modify the file
+    if (existingConfig == output.str()) return;
+  }
+
+  // save the config file
+  xe::filesystem::CreateParentFolder(config_path);
+  std::ofstream file;
+  file.open(xe::to_string(config_path), std::ios::out | std::ios::trunc);
+  file << output.str();
+  file.close();
+}
+
+void SetupConfig(const std::wstring& config_folder) {
+  config::config_folder = config_folder;
+  // check if the user specified a specific config to load
+  if (!cvars::config.empty()) {
+    config_path = xe::to_wstring(cvars::config);
+    if (xe::filesystem::PathExists(config_path)) {
+      ReadConfig(config_path);
+      return;
+    }
+  }
+  // if the user specified a --config argument, but the file doesn't exist,
+  // let's also load the default config
+  if (!config_folder.empty()) {
+    config_path = xe::join_paths(config_folder, config_name);
+    if (xe::filesystem::PathExists(config_path)) {
+      ReadConfig(config_path);
+    }
+    // we only want to save the config if the user is using the default
+    // config, we don't want to override a user created specific config
+    SaveConfig();
+  }
+}
+
+void LoadGameConfig(const std::wstring& title_id) {
+  const auto content_folder = xe::join_paths(config_folder, L"content");
+  const auto game_folder = xe::join_paths(content_folder, title_id);
+  const auto game_config_path = xe::join_paths(game_folder, config_name);
+  if (xe::filesystem::PathExists(game_config_path)) {
+    ReadGameConfig(game_config_path);
+  }
+}
+
+}  // namespace config

src/xenia/config.h

@@ -0,0 +1,10 @@
+#ifndef XENIA_CONFIG_H_
+#define XENIA_CONFIG_H_
+#include <string>
+
+namespace config {
+void SetupConfig(const std::wstring& config_folder);
+void LoadGameConfig(const std::wstring& title_id);
+}  // namespace config
+
+#endif  // XENIA_CONFIG_H_