💥 Major refactor of initialization plumbing

To account for the differences in VST2 plugins and VST3 modules we had
to wrap most of our old functions from `src/plugin/utils.h` in a new
`PluginInfo` struct that gathers all of this information while taking
into account the differences between VST2 and VST3 plugins.

With this change things are also a lot more organized. We can just query
the plugin information we need rather than having to store things
separately or having to recalculate things. This also moved the
responsibility of all the weird `WINEPREFIX` behaviour to a single place
instead of having it spread around `utils.pp`, the initialisation
message, and `host-procoess.cpp`.

src/plugin/host-process.cpp

@@ -86,20 +86,22 @@ void HostProcess::async_log_pipe_lines(patched_async_pipe& pipe,
 
 IndividualHost::IndividualHost(boost::asio::io_context& io_context,
                                Logger& logger,
-                               const HostRequest& plugin_info)
+                               const PluginInfo& plugin_info,
+                               const HostRequest& host_request)
     : HostProcess(io_context, logger),
-      // FIXME: This will require changing for VST3 bundles
-      plugin_arch(find_dll_architecture(plugin_info.plugin_path)),
-      host_path(find_vst_host(plugin_arch, false)),
+      plugin_info(plugin_info),
+      host_path(find_vst_host(plugin_info.native_library_path,
+                              plugin_info.plugin_arch,
+                              false)),
       host(launch_host(host_path,
-                       plugin_type_to_string(plugin_info.plugin_type),
+                       plugin_type_to_string(host_request.plugin_type),
 #ifdef WITH_WINEDBG
-                       plugin_info.plugin_path.filename(),
+                       host_request.plugin_path.filename(),
 #else
-                       plugin_info.plugin_path,
+                       host_request.plugin_path,
 #endif
-                       plugin_info.endpoint_base_dir,
-                       bp::env = set_wineprefix(),
+                       host_request.endpoint_base_dir,
+                       bp::env = plugin_info.create_host_env(),
                        bp::std_out = stdout_pipe,
                        bp::std_err = stderr_pipe
 #ifdef WITH_WINEDBG
@@ -115,10 +117,6 @@ IndividualHost::IndividualHost(boost::asio::io_context& io_context,
 #endif
 }
 
-LibArchitecture IndividualHost::architecture() {
-    return plugin_arch;
-}
-
 fs::path IndividualHost::path() {
     return host_path;
 }
@@ -134,13 +132,15 @@ void IndividualHost::terminate() {
 
 GroupHost::GroupHost(boost::asio::io_context& io_context,
                      Logger& logger,
+                     const PluginInfo& plugin_info,
                      const HostRequest& host_request,
                      Sockets& sockets,
                      std::string group_name)
     : HostProcess(io_context, logger),
-      // FIXME: This will require changing for VST3 bundles
-      plugin_arch(find_dll_architecture(host_request.plugin_path)),
-      host_path(find_vst_host(plugin_arch, true)),
+      plugin_info(plugin_info),
+      host_path(find_vst_host(plugin_info.native_library_path,
+                              plugin_info.plugin_arch,
+                              true)),
       sockets(sockets) {
 #ifdef WITH_WINEDBG
     if (plugin_path.string().find(' ') != std::string::npos) {
@@ -156,25 +156,10 @@ GroupHost::GroupHost(boost::asio::io_context& io_context,
     // other processes will exit. When a plugin's host process has exited, it
     // will try to connect to the socket once more in the case that another
     // process is now listening on it.
-    const bp::environment host_env = set_wineprefix();
-    fs::path wine_prefix;
-    if (auto wine_prefix_envvar = host_env.find("WINEPREFIX");
-        wine_prefix_envvar != host_env.end()) {
-        // This is a bit ugly, but Boost.Process's environment does not have a
-        // graceful way to check for empty environment variables in const
-        // qualified environments
-        wine_prefix = wine_prefix_envvar->to_string();
-    } else {
-        // Fall back to `~/.wine` if this has not been set or detected. This
-        // would happen if the plugin's .dll file is not inside of a Wine
-        // prefix. If this happens, then the Wine instance will be launched in
-        // the default Wine prefix, so we should reflect that here.
-        wine_prefix = fs::path(host_env.at("HOME").to_string()) / ".wine";
-    }
-
     const fs::path endpoint_base_dir = sockets.base_dir;
     const fs::path group_socket_path =
-        generate_group_endpoint(group_name, wine_prefix, plugin_arch);
+        generate_group_endpoint(group_name, plugin_info.normalize_wine_prefix(),
+                                plugin_info.plugin_arch);
     const auto connect = [&io_context, host_request, endpoint_base_dir,
                           group_socket_path]() {
         boost::asio::local::stream_protocol::socket group_socket(io_context);
@@ -194,7 +179,8 @@ GroupHost::GroupHost(boost::asio::io_context& io_context,
         // because it should run independently of this yabridge instance as
         // it will likely outlive it.
         bp::child group_host =
-            launch_host(host_path, group_socket_path, bp::env = host_env,
+            launch_host(host_path, group_socket_path,
+                        bp::env = plugin_info.create_host_env(),
                         bp::std_out = stdout_pipe, bp::std_err = stderr_pipe);
         group_host.detach();
 
@@ -231,10 +217,6 @@ GroupHost::GroupHost(boost::asio::io_context& io_context,
     }
 }
 
-LibArchitecture GroupHost::architecture() {
-    return plugin_arch;
-}
-
 fs::path GroupHost::path() {
     return host_path;
 }