Make JSON reading safer

- Check that the file actually opened before reading it
- If the JSON was discarded, then make just use an empty object

include/store/meta.hpp

@@ -50,19 +50,15 @@ public:
 	std::vector<std::string> GetInstalled(const std::string &unistoreName, const std::string &entry) const;
 
 	void SetUpdated(const std::string &unistoreName, const std::string &entry, const std::string &updated) {
-		if (this->metadataJson.is_discarded()) return;
 		this->metadataJson[unistoreName][entry]["updated"] = updated;
 	};
 
 	void SetMarks(const std::string &unistoreName, const std::string &entry, int marks) {
-		if (this->metadataJson.is_discarded()) return;
 		this->metadataJson[unistoreName][entry]["marks"] = marks;
 	};
 
 	/* TODO: Handle this better. */
 	void SetInstalled(const std::string &unistoreName, const std::string &entry, const std::string &name) {
-		if (this->metadataJson.is_discarded()) return;
-
 		const std::vector<std::string> installs = this->GetInstalled(unistoreName, entry);
 		bool write = true;
 
@@ -82,8 +78,6 @@ public:
 
 	/* Remove installed state from a download list entry. */
 	void RemoveInstalled(const std::string &unistoreName, const std::string &entry, const std::string &name) {
-		if (this->metadataJson.is_discarded()) return;
-
 		const std::vector<std::string> installs = this->GetInstalled(unistoreName, entry);
 		int idx = -1;
 

source/overlays/storeSelect.cpp

@@ -59,9 +59,14 @@ static const std::vector<Structs::ButtonPos> mainButtons = {
 	const std::string &file: The file of the UniStore.
 */
 static void DeleteStore(const std::string &file) {
+	nlohmann::json storeJson;
 	FILE *temp = fopen((std::string(_STORE_PATH) + file).c_str(), "rt");
-	nlohmann::json storeJson = nlohmann::json::parse(temp, nullptr, false);
+	if (temp) {
-	fclose(temp);
+		storeJson = nlohmann::json::parse(temp, nullptr, false);
+		fclose(temp);
+	}
+	if (storeJson.is_discarded())
+		storeJson = {};
 
 	/* Check, if Spritesheet exist on UniStore. */
 	if (storeJson["storeInfo"].contains("sheet") && storeJson["storeInfo"]["sheet"].is_array()) {
@@ -105,9 +110,14 @@ static bool DownloadStore() {
 	if (URL != "") doSheet = DownloadUniStore(URL, -1, file, true);
 
 	if (doSheet) {
+		nlohmann::json storeJson;
 		FILE *temp = fopen(file.c_str(), "rt");
-		nlohmann::json storeJson = nlohmann::json::parse(temp, nullptr, false);
+		if (temp) {
-		fclose(temp);
+			storeJson = nlohmann::json::parse(temp, nullptr, false);
+			fclose(temp);
+		}
+		if (storeJson.is_discarded())
+			storeJson = { };
 
 		if (doSheet) {
 			if (storeJson["storeInfo"].contains("sheetURL") && storeJson["storeInfo"]["sheetURL"].is_array()) {
@@ -158,9 +168,14 @@ static bool UpdateStore(const std::string &URL) {
 	if (URL != "") doSheet = DownloadUniStore(URL, -1, file, false);
 
 	if (doSheet) {
+		nlohmann::json storeJson;
 		FILE *temp = fopen(file.c_str(), "rt");
-		nlohmann::json storeJson = nlohmann::json::parse(temp, nullptr, false);
+		if (temp) {
-		fclose(temp);
+			storeJson = nlohmann::json::parse(temp, nullptr, false);
+			fclose(temp);
+		}
+		if (storeJson.is_discarded())
+			storeJson = { };
 
 		if (doSheet) {
 			if (storeJson["storeInfo"].contains("sheetURL") && storeJson["storeInfo"]["sheetURL"].is_array()) {

source/store/meta.cpp

@@ -43,8 +43,12 @@ Meta::Meta() {
 	}
 
 	FILE *temp = fopen(_META_PATH, "rt");
-	this->metadataJson = nlohmann::json::parse(temp, nullptr, false);
+	if (temp) {
-	fclose(temp);
+		this->metadataJson = nlohmann::json::parse(temp, nullptr, false);
+		fclose(temp);
+	}
+	if (this->metadataJson.is_discarded())
+		this->metadataJson = { };
 
 	if (config->metadata()) this->ImportMetadata();
 }
@@ -59,9 +63,15 @@ void Meta::ImportMetadata() {
 	}
 
 	Msg::DisplayMsg(Lang::get("FETCHING_METADATA"));
-	FILE *old = fopen("sdmc:/3ds/Universal-Updater/updates.json", "r");
+
-	nlohmann::json oldJson = nlohmann::json::parse(old, nullptr, false);
+	nlohmann::json oldJson;
-	fclose(old);
+	FILE *old = fopen("sdmc:/3ds/Universal-Updater/updates.json", "rt");
+	if (old) {
+		oldJson = nlohmann::json::parse(old, nullptr, false);
+		fclose(old);
+	}
+	if (oldJson.is_discarded())
+		oldJson = { };
 
 	std::vector<UniStoreInfo> info = GetUniStoreInfo(_STORE_PATH); // Fetch UniStores.
 
@@ -83,7 +93,6 @@ void Meta::ImportMetadata() {
 	const std::string &entry: The Entry name.
 */
 std::string Meta::GetUpdated(const std::string &unistoreName, const std::string &entry) const {
-	if (this->metadataJson.is_discarded()) return "";
 	if (!this->metadataJson.contains(unistoreName)) return ""; // UniStore Name does not exist.
 
 	if (!this->metadataJson[unistoreName].contains(entry)) return ""; // Entry does not exist.
@@ -103,8 +112,6 @@ std::string Meta::GetUpdated(const std::string &unistoreName, const std::string
 int Meta::GetMarks(const std::string &unistoreName, const std::string &entry) const {
 	int temp = 0;
 
-	if (this->metadataJson.is_discarded()) return temp;
-
 	if (!this->metadataJson.contains(unistoreName)) return temp; // UniStore Name does not exist.
 
 	if (!this->metadataJson[unistoreName].contains(entry)) return temp; // Entry does not exist.
@@ -137,8 +144,6 @@ bool Meta::UpdateAvailable(const std::string &unistoreName, const std::string &e
 	const std::string &entry: The Entry name.
 */
 std::vector<std::string> Meta::GetInstalled(const std::string &unistoreName, const std::string &entry) const {
-	if (this->metadataJson.is_discarded()) return { };
-
 	if (!this->metadataJson.contains(unistoreName)) return { }; // UniStore Name does not exist.
 
 	if (!this->metadataJson[unistoreName].contains(entry)) return { }; // Entry does not exist.

source/store/store.cpp

@@ -231,6 +231,8 @@ void Store::LoadFromFile(const std::string &file) {
 
 	this->storeJson = nlohmann::json::parse(in, nullptr, false);
 	fclose(in);
+	if (this->storeJson.is_discarded())
+		this->storeJson = { };
 
 	/* Check, if valid. */
 	if (this->storeJson.contains("storeInfo") && this->storeJson.contains("storeContent")) {

source/utils/config.cpp

@@ -110,9 +110,13 @@ Config::Config() {
 		this->initialize();
 	}
 
-	FILE *file = fopen("sdmc:/3ds/Universal-Updater/Config.json", "r");
+	FILE *file = fopen("sdmc:/3ds/Universal-Updater/Config.json", "rt");
-	this->json = nlohmann::json::parse(file, nullptr, false);
+	if (file) {
-	fclose(file);
+		this->json = nlohmann::json::parse(file, nullptr, false);
+		fclose(file);
+	}
+	if (this->json.is_discarded())
+		this->json = { };
 
 	/* Let us create a new one. */
 	if (!this->json.contains("Version")) this->initialize();
@@ -174,34 +178,28 @@ void Config::save() {
 
 /* Helper functions. */
 bool Config::getBool(const std::string &key) {
-	if (this->json.is_discarded()) return false;
 	if (!this->json.contains(key)) return false;
 
 	return this->json.at(key).get_ref<const bool &>();
 }
 void Config::setBool(const std::string &key, bool v) {
-	if (this->json.is_discarded()) return;
 	this->json[key] = v;
 };
 
 int Config::getInt(const std::string &key) {
-	if (this->json.is_discarded()) return 0;
 	if (!this->json.contains(key)) return 0;
 
 	return this->json.at(key).get_ref<const int64_t &>();
 }
 void Config::setInt(const std::string &key, int v) {
-	if (this->json.is_discarded()) return;
 	this->json[key] = v;
 };
 
 std::string Config::getString(const std::string &key) {
-	if (this->json.is_discarded()) return "";
 	if (!this->json.contains(key)) return "";
 
 	return this->json.at(key).get_ref<const std::string &>();
 }
 void Config::setString(const std::string &key, const std::string &v) {
-	if (this->json.is_discarded()) return;
 	this->json[key] = v;
 };

source/utils/fileBrowse.cpp

@@ -113,11 +113,15 @@ UniStoreInfo GetInfo(const std::string &file, const std::string &fileName) {
 		if(*(u32*)(fileName.c_str() + fileName.length() - 4) == (1886349435 & ~(1 << 3))) return Temp;
 	}
 
-	nlohmann::json JSON = nullptr;
+	nlohmann::json JSON;
+	FILE *temp = fopen(file.c_str(), "rt");
+	if(temp) {
+		JSON = nlohmann::json::parse(temp, nullptr, false);
+		fclose(temp);
+	}
+	if (JSON.is_discarded())
+		JSON = { };
 
-	FILE *temp = fopen(file.c_str(), "r");
-	JSON = nlohmann::json::parse(temp, nullptr, false);
-	fclose(temp);
 
 	if (!JSON.contains("storeInfo")) return Temp; // storeInfo does not exist.
 

source/utils/lang.cpp

@@ -42,14 +42,22 @@ void Lang::load(const std::string &lang) {
 	/* Check if exist. */
 	if (access(("romfs:/lang/" + lang + "/app.json").c_str(), F_OK) == 0) {
 		values = fopen(("romfs:/lang/" + lang + "/app.json").c_str(), "rt");
-		appJson = nlohmann::json::parse(values, nullptr, false);
+		if (values) {
-		fclose(values);
+			appJson = nlohmann::json::parse(values, nullptr, false);
+			fclose(values);
+		}
+		if (appJson.is_discarded())
+			appJson = { };
 		return;
 
 	} else {
 		values = fopen("romfs:/lang/en/app.json", "rt");
-		appJson = nlohmann::json::parse(values, nullptr, false);
+		if (values) {
-		fclose(values);
+			appJson = nlohmann::json::parse(values, nullptr, false);
+			fclose(values);
+		}
+		if (appJson.is_discarded())
+			appJson = { };
 		return;
 	}
 }