Add a plugin type tag and conversion functions

src/common/plugins.cpp

@@ -5,7 +5,7 @@
 
 namespace fs = boost::filesystem;
 
-LibArchitecture find_dll_architecture(fs::path plugin_path) {
+LibArchitecture find_dll_architecture(const fs::path& plugin_path) {
     std::ifstream file(plugin_path, std::ifstream::binary | std::ifstream::in);
 
     // The linker will place the offset where the PE signature is placed at the
@@ -51,3 +51,23 @@ LibArchitecture find_dll_architecture(fs::path plugin_path) {
               << std::hex << machine_type;
     throw std::runtime_error(error_msg.str());
 }
+
+PluginType plugin_type_from_string(const std::string& plugin_type) {
+    if (plugin_type == "vst2") {
+        return PluginType::vst2;
+    } else if (plugin_type == "vst3") {
+        return PluginType::vst3;
+    } else {
+        return PluginType::unknown;
+    }
+}
+
+std::string plugin_type_to_string(const PluginType& plugin_type) {
+    if (plugin_type == PluginType::vst2) {
+        return "vst2";
+    } else if (plugin_type == PluginType::vst3) {
+        return "vst3";
+    } else {
+        return "unknown";
+    }
+}

src/common/plugins.h

@@ -29,6 +29,19 @@
  */
 enum class LibArchitecture { dll_32, dll_64 };
 
+/**
+ * A tag to differentiate between different plugin types.
+ * `plugin_tyep_to_string()` and `plugin_type_from_string()` can be used to
+ * convert these values to and from strings. The string form is used as a
+ * command line argument for the individual Wine host applications, and the enum
+ * form is passed directly in `GroupRequest`.
+ *
+ * The `unkonwn` tag is not used directly, but in the event that we do call
+ * `plugin_type_from_string()` with some invalid value we can use it to
+ * gracefully show an error message without resorting to exceptions.
+ */
+enum class PluginType { vst2, vst3, unknown };
+
 /**
  * Determine the architecture of a `.dll` file based on the file header.
  *
@@ -40,4 +53,7 @@ enum class LibArchitecture { dll_32, dll_64 };
  * @return The detected architecture.
  * @throw std::runtime_error If the file is not a .dll file.
  */
-LibArchitecture find_dll_architecture(boost::filesystem::path);
+LibArchitecture find_dll_architecture(const boost::filesystem::path&);
+
+PluginType plugin_type_from_string(const std::string& plugin_type);
+std::string plugin_type_to_string(const PluginType& plugin_type);