addcont: add user add-ons with --addcont and a launcher list

src/common/additionalContent.cpp

@@ -109,4 +109,23 @@ std::vector<AddContentEntry> FindAddContent(const std::filesystem::path& dir,
 	return entries;
 }
 
+std::optional<AddContentEntry> ParseAddContent(std::string_view value) {
+	static const std::regex label_pattern("^[A-Z0-9]{16}$");
+	const auto              eq    = value.find('=');
+	const auto              label = value.substr(0, eq);
+	if (!std::regex_match(label.begin(), label.end(), label_pattern)) {
+		return std::nullopt;
+	}
+
+	AddContentEntry entry {{}, std::string(label), {}, {}};
+	if (eq != std::string_view::npos) {
+		entry.mount_dir = PathFromUtf8(FixFilenameSlash(value.substr(eq + 1)));
+		std::error_code ec;
+		if (!std::filesystem::is_directory(entry.mount_dir, ec)) {
+			return std::nullopt;
+		}
+	}
+	return entry;
+}
+
 } // namespace Common

src/common/additionalContent.h

@@ -2,7 +2,9 @@
 #define KYTY_COMMON_ADDITIONAL_CONTENT_H_
 
 #include <filesystem>
+#include <optional>
 #include <string>
+#include <string_view>
 #include <vector>
 
 namespace Common {
@@ -10,7 +12,7 @@ namespace Common {
 struct AddContentEntry {
 	std::string           content_id;
 	std::string           entitlement_label;
-	std::filesystem::path mount_dir;
+	std::filesystem::path mount_dir; // Empty for an add-on without extra data.
 	std::string           title;
 };
 
@@ -18,6 +20,9 @@ struct AddContentEntry {
 std::vector<AddContentEntry> FindAddContent(const std::filesystem::path& dir,
                                             const std::string&           title_id);
 
+// Parses a user add-on: "LABEL" without extra data, or "LABEL=DIR" with its data in DIR.
+std::optional<AddContentEntry> ParseAddContent(std::string_view value);
+
 } // namespace Common
 
 #endif /* KYTY_COMMON_ADDITIONAL_CONTENT_H_ */