Move dbus code to a separate process to allow gpu-screen-recorder to use cap_sys_nice for better recording performance on amd

dbus/client/dbus_client.h

@@ -0,0 +1,36 @@
+#ifndef GSR_DBUS_CLIENT_H
+#define GSR_DBUS_CLIENT_H
+
+/*
+    Using a client-server architecture is needed for dbus because cap_sys_nice doesn't work with desktop portal.
+    The main binary has cap_sys_nice and we launch a new child-process without it which uses uses desktop portal.
+*/
+
+#include "../portal.h"
+#include <stdbool.h>
+#include <stdint.h>
+#include <signal.h>
+
+typedef struct {
+    int socket_pair[2];
+    char *screencast_restore_token;
+    pid_t pid;
+} gsr_dbus_client;
+
+/* Blocking. TODO: Make non-blocking */
+bool gsr_dbus_client_init(gsr_dbus_client *self, const char *screencast_restore_token);
+void gsr_dbus_client_deinit(gsr_dbus_client *self);
+
+/* The follow functions should be called in order to setup ScreenCast properly */
+/* These functions that return an int return the response status code */
+int gsr_dbus_client_screencast_create_session(gsr_dbus_client *self, char *session_handle, size_t session_handle_size);
+/*
+    |capture_type| is a bitmask of gsr_portal_capture_type values. gsr_portal_capture_type values that are not supported by the desktop portal will be ignored.
+    |gsr_portal_cursor_mode| is a bitmask of gsr_portal_cursor_mode values. gsr_portal_cursor_mode values that are not supported will be ignored.
+*/
+int gsr_dbus_client_screencast_select_sources(gsr_dbus_client *self, const char *session_handle, uint32_t capture_type, uint32_t cursor_mode);
+int gsr_dbus_client_screencast_start(gsr_dbus_client *self, const char *session_handle, uint32_t *pipewire_node);
+bool gsr_dbus_client_screencast_open_pipewire_remote(gsr_dbus_client *self, const char *session_handle, int *pipewire_fd);
+const char* gsr_dbus_client_screencast_get_restore_token(gsr_dbus_client *self);
+
+#endif /* GSR_DBUS_CLIENT_H */