Implement Tray Icons

This commit implements the StatusNotifierItem protocol, and enables
swaybar to show tray icons. It also uses `xembedsniproxy` in order to
communicate with xembed applications.
The tray is completely optional, and can be disabled on compile time
with the `enable-tray` option. Or on runtime with the bar config option
`tray_output none`.

Overview of changes:
In swaybar very little is changed outside the tray subfolder except
that all events are now polled in `event_loop.c`, this creates no
functional difference.

Six bar configuration options were added, these are detailed in
sway-bar(5)

The tray subfolder is where all protocol implementation takes place and
is organised as follows:

tray/sni_watcher.c:
	This file contains the StatusNotifierWatcher. It keeps track of
	items and hosts and reports when they come or go.
tray/tray.c
	This file contains the StatusNotifierHost. It keeps track of
	sway's version of the items and represents the tray itself.
tray/sni.c
	This file contains the StatusNotifierItem struct and all
	communication with individual items.
tray/icon.c
	This file implements the icon theme protocol. It allows for
	finding icons by name, rather than by pixmap.
tray/dbus.c
	This file allows for asynchronous DBus communication.

See #986 #343

1 files changed, 101 insertions, 34 deletions

diff --git a/swaybar/bar.c b/swaybar/bar.c
index abde1cc9..cdaf6a37 100644
--- a/swaybar/bar.c
+++ b/swaybar/bar.c
@@ -7,10 +7,17 @@
 #include <sys/wait.h>
 #include <signal.h>
 #include <poll.h>
+#ifdef ENABLE_TRAY
+#include <dbus/dbus.h>
+#include "swaybar/tray/sni_watcher.h"
+#include "swaybar/tray/tray.h"
+#include "swaybar/tray/sni.h"
+#endif
 #include "swaybar/ipc.h"
 #include "swaybar/render.h"
 #include "swaybar/config.h"
 #include "swaybar/status_line.h"
+#include "swaybar/event_loop.h"
 #include "swaybar/bar.h"
 #include "ipc-client.h"
 #include "list.h"
@@ -50,18 +57,39 @@ static void spawn_status_cmd_proc(struct bar *bar) {
         }
 }
 
+#ifdef ENABLE_TRAY
+static void spawn_xembed_sni_proxy() {
+        pid_t pid = fork();
+        if (pid == 0) {
+                int wstatus;
+                do {
+                        pid = fork();
+                        if (pid == 0) {
+                                execlp("xembedsniproxy", "xembedsniproxy", NULL);
+                                _exit(EXIT_FAILURE);
+                        }
+                        waitpid(pid, &wstatus, 0);
+                } while (!WIFEXITED(wstatus));
+                _exit(EXIT_FAILURE);
+        }
+}
+#endif
+
 struct output *new_output(const char *name) {
         struct output *output = malloc(sizeof(struct output));
         output->name = strdup(name);
         output->window = NULL;
         output->registry = NULL;
         output->workspaces = create_list();
+#ifdef ENABLE_TRAY
+        output->items = create_list();
+#endif
         return output;
 }
 
 static void mouse_button_notify(struct window *window, int x, int y,
                 uint32_t button, uint32_t state_w) {
-        sway_log(L_DEBUG, "Mouse button %d clicked at %d %d %d\n", button, x, y, state_w);
+        sway_log(L_DEBUG, "Mouse button %d clicked at %d %d %d", button, x, y, state_w);
         if (!state_w) {
                 return;
         }
@@ -92,6 +120,30 @@ static void mouse_button_notify(struct window *window, int x, int y,
                         break;
                 }
         }
+
+#ifdef ENABLE_TRAY
+        uint32_t tray_padding = swaybar.config->tray_padding;
+        int tray_width = window->width * window->scale;
+
+        for (int i = 0; i < clicked_output->items->length; ++i) {
+                struct sni_icon_ref *item =
+                         clicked_output->items->items[i];
+                int icon_width = cairo_image_surface_get_width(item->icon);
+
+                tray_width -= tray_padding;
+                if (x <= tray_width && x >= tray_width - icon_width) {
+                        if (button == swaybar.config->activate_button) {
+                                sni_activate(item->ref, x, y);
+                        } else if (button == swaybar.config->context_button) {
+                                sni_context_menu(item->ref, x, y);
+                        } else if (button == swaybar.config->secondary_button) {
+                                sni_secondary(item->ref, x, y);
+                        }
+                        break;
+                }
+                tray_width -= icon_width;
+        }
+#endif
 }
 
 static void mouse_scroll_notify(struct window *window, enum scroll_direction direction) {
@@ -136,6 +188,9 @@ void bar_setup(struct bar *bar, const char *socket_path, const char *bar_id) {
         /* initialize bar with default values */
         bar_init(bar);
 
+        /* Initialize event loop lists */
+        init_event_loop();
+
         /* connect to sway ipc */
         bar->ipc_socketfd = ipc_open_socket(socket_path);
         bar->ipc_event_socketfd = ipc_open_socket(socket_path);
@@ -178,23 +233,54 @@ void bar_setup(struct bar *bar, const char *socket_path, const char *bar_id) {
         }
         /* spawn status command */
         spawn_status_cmd_proc(bar);
+
+#ifdef ENABLE_TRAY
+        // We should have at least one output to serve the tray to
+        if (!swaybar.config->tray_output || strcmp(swaybar.config->tray_output, "none") != 0) {
+                /* Connect to the D-Bus */
+                dbus_init();
+
+                /* Start the SNI watcher */
+                init_sni_watcher();
+
+                /* Start the SNI host */
+                init_tray();
+
+                /* Start xembedsniproxy */
+                spawn_xembed_sni_proxy();
+        }
+#endif
 }
 
-void bar_run(struct bar *bar) {
-        int pfds = bar->outputs->length + 2;
-        struct pollfd *pfd = malloc(pfds * sizeof(struct pollfd));
-        bool dirty = true;
+bool dirty = true;
 
-        pfd[0].fd = bar->ipc_event_socketfd;
-        pfd[0].events = POLLIN;
-        pfd[1].fd = bar->status_read_fd;
-        pfd[1].events = POLLIN;
+static void respond_ipc(int fd, short mask, void *_bar) {
+        struct bar *bar = (struct bar *)_bar;
+        sway_log(L_DEBUG, "Got IPC event.");
+        dirty = handle_ipc_event(bar);
+}
+
+static void respond_command(int fd, short mask, void *_bar) {
+        struct bar *bar = (struct bar *)_bar;
+        dirty = handle_status_line(bar);
+}
+
+static void respond_output(int fd, short mask, void *_output) {
+        struct output *output = (struct output *)_output;
+        if (wl_display_dispatch(output->registry->display) == -1) {
+                sway_log(L_ERROR, "failed to dispatch wl: %d", errno);
+        }
+}
+
+void bar_run(struct bar *bar) {
+        add_event(bar->ipc_event_socketfd, POLLIN, respond_ipc, bar);
+        add_event(bar->status_read_fd, POLLIN, respond_command, bar);
 
         int i;
         for (i = 0; i < bar->outputs->length; ++i) {
                 struct output *output = bar->outputs->items[i];
-                pfd[i+2].fd = wl_display_get_fd(output->registry->display);
-                pfd[i+2].events = POLLIN;
+                add_event(wl_display_get_fd(output->registry->display),
+                                POLLIN, respond_output, output);
         }
 
         while (1) {
@@ -212,29 +298,10 @@ void bar_run(struct bar *bar) {
 
                 dirty = false;
 
-                poll(pfd, pfds, -1);
-
-                if (pfd[0].revents & POLLIN) {
-                        sway_log(L_DEBUG, "Got IPC event.");
-                        dirty = handle_ipc_event(bar);
-                }
-
-                if (bar->config->status_command && pfd[1].revents & POLLIN) {
-                        sway_log(L_DEBUG, "Got update from status command.");
-                        dirty = handle_status_line(bar);
-                }
-
-                // dispatch wl_display events
-                for (i = 0; i < bar->outputs->length; ++i) {
-                        struct output *output = bar->outputs->items[i];
-                        if (pfd[i+2].revents & POLLIN) {
-                                if (wl_display_dispatch(output->registry->display) == -1) {
-                                        sway_log(L_ERROR, "failed to dispatch wl: %d", errno);
-                                }
-                        } else {
-                                wl_display_dispatch_pending(output->registry->display);
-                        }
-                }
+                event_loop_poll();
+#ifdef ENABLE_TRAY
+                dispatch_dbus();
+#endif
         }
 }