LaunchServer+LibDesktop: Add API to list handlers for a given URL

You can now ask for a list of applications that can handle opening
a given URL. This will be useful for creating context menus.

Libraries/LibDesktop/Launcher.cpp

@@ -57,4 +57,10 @@ bool Launcher::open(const URL& url)
     return connection->send_sync<Messages::LaunchServer::OpenUrl>(url.to_string())->response();
 }
 
+Vector<String> Launcher::get_handlers_for_url(const URL& url)
+{
+    auto connection = LaunchServerConnection::construct();
+    return connection->send_sync<Messages::LaunchServer::GetHandlersForURL>(url.to_string())->handlers();
+}
+
 }

Libraries/LibDesktop/Launcher.h

@@ -30,9 +30,14 @@
 
 namespace Desktop {
 
+struct Opener {
+
+};
+
 class Launcher {
 public:
     static bool open(const URL&);
+    static Vector<String> get_handlers_for_url(const URL&);
 };
 
 }

Services/LaunchServer/ClientConnection.cpp

@@ -59,4 +59,12 @@ OwnPtr<Messages::LaunchServer::OpenUrlResponse> ClientConnection::handle(const M
     auto result = Launcher::the().open_url(url);
     return make<Messages::LaunchServer::OpenUrlResponse>(result);
 }
+
+OwnPtr<Messages::LaunchServer::GetHandlersForURLResponse> ClientConnection::handle(const Messages::LaunchServer::GetHandlersForURL& request)
+{
+    URL url(request.url());
+    auto result = Launcher::the().handlers_for_url(url);
+    return make<Messages::LaunchServer::GetHandlersForURLResponse>(result);
+}
+
 }

Services/LaunchServer/ClientConnection.h

@@ -44,5 +44,6 @@ private:
 
     virtual OwnPtr<Messages::LaunchServer::GreetResponse> handle(const Messages::LaunchServer::Greet&) override;
     virtual OwnPtr<Messages::LaunchServer::OpenUrlResponse> handle(const Messages::LaunchServer::OpenUrl&) override;
+    virtual OwnPtr<Messages::LaunchServer::GetHandlersForURLResponse> handle(const Messages::LaunchServer::GetHandlersForURL&) override;
 };
 }

Services/LaunchServer/LaunchServer.ipc

@@ -2,4 +2,5 @@ endpoint LaunchServer = 101
 {
     Greet() => (i32 client_id)
     OpenUrl(String url) => (bool response)
+    GetHandlersForURL(String url) => (Vector<String> handlers)
 }

Services/LaunchServer/Launcher.cpp

@@ -25,6 +25,7 @@
  */
 
 #include "Launcher.h"
+#include <AK/FileSystemPath.h>
 #include <LibCore/ConfigFile.h>
 #include <stdio.h>
 #include <sys/stat.h>
@@ -57,6 +58,14 @@ void Launcher::load_config(const Core::ConfigFile& cfg)
     }
 }
 
+Vector<String> Launcher::handlers_for_url(const URL& url)
+{
+    if (url.protocol() == "file")
+        return handlers_for_path(url.path());
+
+    return { m_protocol_handlers.get(url.protocol()).value_or(m_protocol_handlers.get("*").value_or({})) };
+}
+
 bool Launcher::open_url(const URL& url)
 {
     if (url.protocol() == "file")
@@ -98,6 +107,22 @@ bool Launcher::open_with_handlers(const HashMap<String, String>& handlers, const
     return spawn(default_program, argument);
 }
 
+Vector<String> Launcher::handlers_for_path(const String& path)
+{
+    struct stat st;
+    if (stat(path.characters(), &st) < 0) {
+        perror("stat");
+        return {};
+    }
+
+    // TODO: Make directory opening configurable
+    if (S_ISDIR(st.st_mode))
+        return { "/bin/FileManager" };
+
+    auto extension = FileSystemPath(path).extension().to_lowercase();
+    return { m_file_handlers.get(extension).value_or(m_file_handlers.get("*").value_or({})) };
+}
+
 bool Launcher::open_file_url(const URL& url)
 {
     struct stat st;

Services/LaunchServer/Launcher.h

@@ -39,11 +39,13 @@ public:
 
     void load_config(const Core::ConfigFile&);
     bool open_url(const URL&);
+    Vector<String> handlers_for_url(const URL&);
 
 private:
     HashMap<String, String> m_protocol_handlers;
     HashMap<String, String> m_file_handlers;
 
+    Vector<String> handlers_for_path(const String&);
     bool open_file_url(const URL&);
     bool open_with_handlers(const HashMap<String, String>& handlers, const String key, const String argument, const String default_program);
 };