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

5 files changed, 1822 insertions, 0 deletions

diff --git a/swaybar/tray/dbus.c b/swaybar/tray/dbus.c
new file mode 100644
index 00000000..333d398e
--- /dev/null
+++ b/swaybar/tray/dbus.c
@@ -0,0 +1,189 @@
+#define _XOPEN_SOURCE 500
+#include <stdio.h>
+#include <stdlib.h>
+#include <stdint.h>
+#include <stdbool.h>
+#include <poll.h>
+#include <signal.h>
+#include <time.h>
+#include <dbus/dbus.h>
+#include "swaybar/tray/dbus.h"
+#include "swaybar/event_loop.h"
+#include "log.h"
+
+DBusConnection *conn = NULL;
+
+static void dispatch_watch(int fd, short mask, void *data) {
+        sway_log(L_DEBUG, "Dispatching watch");
+        DBusWatch *watch = data;
+
+        if (!dbus_watch_get_enabled(watch)) {
+                return;
+        }
+
+        uint32_t flags = 0;
+
+        if (mask & POLLIN) {
+                flags |= DBUS_WATCH_READABLE;
+        } if (mask & POLLOUT) {
+                flags |= DBUS_WATCH_WRITABLE;
+        } if (mask & POLLHUP) {
+                flags |= DBUS_WATCH_HANGUP;
+        } if (mask & POLLERR) {
+                flags |= DBUS_WATCH_ERROR;
+        }
+
+        dbus_watch_handle(watch, flags);
+}
+
+static dbus_bool_t add_watch(DBusWatch *watch, void *_data) {
+        if (!dbus_watch_get_enabled(watch)) {
+                // Watch should not be polled
+                return TRUE;
+        }
+
+        short mask = 0;
+        uint32_t flags = dbus_watch_get_flags(watch);
+
+        if (flags & DBUS_WATCH_READABLE) {
+                mask |= POLLIN;
+        } if (flags & DBUS_WATCH_WRITABLE) {
+                mask |= POLLOUT;
+        }
+
+        int fd = dbus_watch_get_unix_fd(watch);
+
+        sway_log(L_DEBUG, "Adding DBus watch fd: %d", fd);
+        add_event(fd, mask, dispatch_watch, watch);
+
+        return TRUE;
+}
+
+static void remove_watch(DBusWatch *watch, void *_data) {
+        int fd = dbus_watch_get_unix_fd(watch);
+
+        remove_event(fd);
+}
+
+static void dispatch_timeout(timer_t timer, void *data) {
+        sway_log(L_DEBUG, "Dispatching DBus timeout");
+        DBusTimeout *timeout = data;
+
+        if (dbus_timeout_get_enabled(timeout)) {
+                dbus_timeout_handle(timeout);
+        }
+}
+
+static dbus_bool_t add_timeout(DBusTimeout *timeout, void *_data) {
+        if (!dbus_timeout_get_enabled(timeout)) {
+                return TRUE;
+        }
+
+        timer_t *timer = malloc(sizeof(timer_t));
+        if (!timer) {
+                sway_log(L_ERROR, "Cannot allocate memory");
+                return FALSE;
+        }
+        struct sigevent ev = {
+                .sigev_notify = SIGEV_NONE,
+        };
+
+        if (timer_create(CLOCK_MONOTONIC, &ev, timer)) {
+                sway_log(L_ERROR, "Could not create DBus timer");
+                return FALSE;
+        }
+
+        int interval = dbus_timeout_get_interval(timeout);
+        int interval_sec = interval / 1000;
+        int interval_msec = (interval_sec * 1000) - interval;
+
+        struct timespec period = {
+                (time_t) interval_sec,
+                ((long) interval_msec) * 1000 * 1000,
+        };
+        struct itimerspec time = {
+                period,
+                period,
+        };
+
+        timer_settime(*timer, 0, &time, NULL);
+
+        dbus_timeout_set_data(timeout, timer, free);
+
+        sway_log(L_DEBUG, "Adding DBus timeout. Interval: %ds %dms", interval_sec, interval_msec);
+        add_timer(*timer, dispatch_timeout, timeout);
+
+        return TRUE;
+}
+static void remove_timeout(DBusTimeout *timeout, void *_data) {
+        timer_t *timer = (timer_t *) dbus_timeout_get_data(timeout);
+        sway_log(L_DEBUG, "Removing DBus timeout.");
+
+        if (timer) {
+                remove_timer(*timer);
+        }
+}
+
+static bool should_dispatch = true;
+
+static void dispatch_status(DBusConnection *connection, DBusDispatchStatus new_status,
+                void *_data) {
+        if (new_status == DBUS_DISPATCH_DATA_REMAINS) {
+                should_dispatch = true;
+        }
+}
+
+/* Public functions below */
+
+void dispatch_dbus() {
+        if (!should_dispatch) {
+                return;
+        }
+
+        DBusDispatchStatus status;
+
+        do {
+                status = dbus_connection_dispatch(conn);
+        } while (status == DBUS_DISPATCH_DATA_REMAINS);
+
+        if (status != DBUS_DISPATCH_COMPLETE) {
+                sway_log(L_ERROR, "Cannot dispatch dbus events: %d", status);
+        }
+
+        should_dispatch = false;
+}
+
+int dbus_init() {
+        DBusError error;
+        dbus_error_init(&error);
+
+        conn = dbus_bus_get(DBUS_BUS_SESSION, &error);
+        dbus_connection_set_exit_on_disconnect(conn, FALSE);
+        if (dbus_error_is_set(&error)) {
+                sway_log(L_ERROR, "Cannot get bus connection: %s\n", error.message);
+                conn = NULL;
+                return -1;
+        }
+
+        sway_log(L_INFO, "Unique name: %s\n", dbus_bus_get_unique_name(conn));
+
+        // Will be called if dispatch status changes
+        dbus_connection_set_dispatch_status_function(conn, dispatch_status, NULL, NULL);
+
+        if (!dbus_connection_set_watch_functions(conn, add_watch, remove_watch,
+                        NULL, NULL, NULL)) {
+                dbus_connection_set_watch_functions(conn, NULL, NULL, NULL, NULL, NULL);
+                sway_log(L_ERROR, "Failed to activate DBUS watch functions");
+                return -1;
+        }
+
+        if (!dbus_connection_set_timeout_functions(conn, add_timeout, remove_timeout,
+                        NULL, NULL, NULL)) {
+                dbus_connection_set_watch_functions(conn, NULL, NULL, NULL, NULL, NULL);
+                dbus_connection_set_timeout_functions(conn, NULL, NULL, NULL, NULL, NULL);
+                sway_log(L_ERROR, "Failed to activate DBUS timeout functions");
+                return -1;
+        }
+
+        return 0;
+}
diff --git a/swaybar/tray/icon.c b/swaybar/tray/icon.c
new file mode 100644
index 00000000..29151a74
--- /dev/null
+++ b/swaybar/tray/icon.c
@@ -0,0 +1,404 @@
+#define _XOPEN_SOURCE 500
+#define _POSIX_C_SOURCE 200809L
+#include <stdio.h>
+#include <stdlib.h>
+#include <unistd.h>
+#include <string.h>
+#include <dirent.h>
+#include <sys/stat.h>
+#include <stdbool.h>
+#include <stdint.h>
+#include <limits.h>
+#include "swaybar/tray/icon.h"
+#include "swaybar/bar.h"
+#include "swaybar/config.h"
+#include "stringop.h"
+#include "log.h"
+
+/**
+ * REVIEW:
+ * This file repeats lots of "costly" operations that are the same for every
+ * icon. It's possible to create a dictionary or some other structure to cache
+ * these, though it may complicate things somewhat.
+ *
+ * Also parsing (index.theme) is currently pretty messy, so that could be made
+ * much better as well. Over all, things work, but are not optimal.
+ */
+
+/* Finds all themes that the given theme inherits */
+static list_t *find_inherits(const char *theme_dir) {
+        const char inherits[] = "Inherits";
+        const char index_name[] = "index.theme";
+        list_t *themes = create_list();
+        FILE *index = NULL;
+        char *path = malloc(strlen(theme_dir) + sizeof(index_name));
+        if (!path) {
+                goto fail;
+        }
+        if (!themes) {
+                goto fail;
+        }
+
+        strcpy(path, theme_dir);
+        strcat(path, index_name);
+
+        index = fopen(path, "r");
+        if (!index) {
+                goto fail;
+        }
+
+        char *buf = NULL;
+        size_t n = 0;
+        while (!feof(index)) {
+                getline(&buf, &n, index);
+                if (n <= sizeof(inherits) + 1) {
+                        continue;
+                }
+                if (strncmp(inherits, buf, sizeof(inherits) - 1) == 0) {
+                        char *themestr = buf + sizeof(inherits);
+                        themes = split_string(themestr, ",");
+                        break;
+                }
+        }
+        free(buf);
+
+fail:
+        free(path);
+        if (index) {
+                fclose(index);
+        }
+        return themes;
+}
+
+static bool isdir(const char *path) {
+        struct stat statbuf;
+        if (stat(path, &statbuf) != -1) {
+                if (S_ISDIR(statbuf.st_mode)) {
+                        return true;
+                }
+        }
+        return false;
+
+}
+
+/**
+ * Returns the directory of a given theme if it exists.
+ * The returned pointer must be freed.
+ */
+static char *find_theme_dir(const char *theme) {
+        char *basedir;
+        char *icon_dir;
+
+        if (!theme) {
+                return NULL;
+        }
+
+        if (!(icon_dir = malloc(1024))) {
+                sway_log(L_ERROR, "Out of memory!");
+                goto fail;
+        }
+
+        if ((basedir = getenv("HOME"))) {
+                if (snprintf(icon_dir, 1024, "%s/.icons/%s", basedir, theme) >= 1024) {
+                        sway_log(L_ERROR, "Path too long to render");
+                        // XXX perhaps just goto trying in /usr/share? This
+                        // shouldn't happen anyway, but might with a long global
+                        goto fail;
+                }
+
+                if (isdir(icon_dir)) {
+                        return icon_dir;
+                }
+        }
+
+        if ((basedir = getenv("XDG_DATA_DIRS"))) {
+                if (snprintf(icon_dir, 1024, "%s/icons/%s", basedir, theme) >= 1024) {
+                        sway_log(L_ERROR, "Path too long to render");
+                        // ditto
+                        goto fail;
+                }
+
+                if (isdir(icon_dir)) {
+                        return icon_dir;
+                }
+        }
+
+        // Spec says use "/usr/share/pixmaps/", but I see everything in
+        // "/usr/share/icons/" look it both, I suppose.
+        if (snprintf(icon_dir, 1024, "/usr/share/pixmaps/%s", theme) >= 1024) {
+                sway_log(L_ERROR, "Path too long to render");
+                goto fail;
+        }
+        if (isdir(icon_dir)) {
+                return icon_dir;
+        }
+
+        if (snprintf(icon_dir, 1024, "/usr/share/icons/%s", theme) >= 1024) {
+                sway_log(L_ERROR, "Path too long to render");
+                goto fail;
+        }
+        if (isdir(icon_dir)) {
+                return icon_dir;
+        }
+
+fail:
+        free(icon_dir);
+        sway_log(L_ERROR, "Could not find dir for theme: %s", theme);
+        return NULL;
+}
+
+/**
+ * Returns all theme dirs needed to be looked in for an icon.
+ * Does not check for duplicates
+ */
+static list_t *find_all_theme_dirs(const char *theme) {
+        list_t *dirs = create_list();
+        if (!dirs) {
+                return NULL;
+        }
+        char *dir = find_theme_dir(theme);
+        if (dir) {
+                list_add(dirs, dir);
+                list_t *inherits = find_inherits(dir);
+                list_cat(dirs, inherits);
+                list_free(inherits);
+        }
+        dir = find_theme_dir("hicolor");
+        if (dir) {
+                list_add(dirs, dir);
+        }
+
+        return dirs;
+}
+
+struct subdir {
+        int size;
+        char name[];
+};
+
+static int subdir_str_cmp(const void *_subdir, const void *_str) {
+        const struct subdir *subdir = _subdir;
+        const char *str = _str;
+        return strcmp(subdir->name, str);
+}
+/**
+ * Helper to find_subdirs. Acts similar to `split_string(subdirs, ",")` but
+ * generates a list of struct subdirs
+ */
+static list_t *split_subdirs(char *subdir_str) {
+        list_t *subdir_list = create_list();
+        char *copy = strdup(subdir_str);
+        if (!subdir_list || !copy) {
+                list_free(subdir_list);
+                free(copy);
+                return NULL;
+        }
+
+        char *token;
+        token = strtok(copy, ",");
+        while(token) {
+                int len = strlen(token) + 1;
+                struct subdir *subdir =
+                        malloc(sizeof(struct subdir) + sizeof(char [len]));
+                if (!subdir) {
+                        // Return what we have
+                        return subdir_list;
+                }
+                subdir->size = 0;
+                strcpy(subdir->name, token);
+
+                list_add(subdir_list, subdir);
+
+                token = strtok(NULL, ",");
+        }
+        free(copy);
+
+        return subdir_list;
+}
+/**
+ * Returns a list of all subdirectories of a theme.
+ * Take note: the subdir names are all relative to `theme_dir` and must be
+ * combined with it to form a valid directory.
+ *
+ * Each member of the list is of type (struct subdir *) this struct contains
+ * the name of the subdir, along with size information. These must be freed
+ * bye the caller.
+ *
+ * This currently ignores min and max sizes of icons.
+ */
+static list_t* find_theme_subdirs(const char *theme_dir) {
+        const char index_name[] = "/index.theme";
+        list_t *dirs = NULL;
+        char *path = malloc(strlen(theme_dir) + sizeof(index_name));
+        FILE *index = NULL;
+        if (!path) {
+                sway_log(L_ERROR, "Failed to allocate memory");
+                goto fail;
+        }
+
+        strcpy(path, theme_dir);
+        strcat(path, index_name);
+
+        index = fopen(path, "r");
+        if (!index) {
+                sway_log(L_ERROR, "Could not open file: %s", path);
+                goto fail;
+        }
+
+        char *buf = NULL;
+        size_t n = 0;
+        while (!feof(index)) {
+                const char directories[] = "Directories";
+                getline(&buf, &n, index);
+                if (n <= sizeof(directories) + 1) {
+                        continue;
+                }
+                if (strncmp(directories, buf, sizeof(directories) - 1) == 0) {
+                        char *dirstr = buf + sizeof(directories);
+                        dirs = split_subdirs(dirstr);
+                        break;
+                }
+        }
+        // Now, find the size of each dir
+        struct subdir *current_subdir = NULL;
+        while (!feof(index)) {
+                const char size[] = "Size";
+                getline(&buf, &n, index);
+
+                if (buf[0] == '[') {
+                        int len = strlen(buf);
+                        if (buf[len-1] == '\n') {
+                                len--;
+                        }
+                        // replace ']'
+                        buf[len-1] = '\0';
+
+                        int index;
+                        if ((index = list_seq_find(dirs, subdir_str_cmp, buf+1)) != -1) {
+                                current_subdir = (dirs->items[index]);
+                        }
+                }
+
+                if (strncmp(size, buf, sizeof(size) - 1) == 0) {
+                        if (current_subdir) {
+                                current_subdir->size = atoi(buf + sizeof(size));
+                        }
+                }
+        }
+        free(buf);
+fail:
+        free(path);
+        if (index) {
+                fclose(index);
+        }
+        return dirs;
+}
+
+/* Returns the file of an icon given its name and size */
+static char *find_icon_file(const char *name, int size) {
+        int namelen = strlen(name);
+        list_t *dirs = find_all_theme_dirs(swaybar.config->icon_theme);
+        if (!dirs) {
+                return NULL;
+        }
+        int min_size_diff = INT_MAX;
+        char *current_file = NULL;
+
+        for (int i = 0; i < dirs->length; ++i) {
+                char *dir = dirs->items[i];
+                list_t *subdirs = find_theme_subdirs(dir);
+
+                if (!subdirs) {
+                        continue;
+                }
+
+                for (int i = 0; i < subdirs->length; ++i) {
+                        struct subdir *subdir = subdirs->items[i];
+
+                        // Only use an unsized if we don't already have a
+                        // canidate this should probably change to allow svgs
+                        if (!subdir->size && current_file) {
+                                continue;
+                        }
+
+                        int size_diff = abs(size - subdir->size);
+
+                        if (size_diff >= min_size_diff) {
+                                continue;
+                        }
+
+                        char *path = malloc(strlen(subdir->name) + strlen(dir) + 2);
+
+                        strcpy(path, dir);
+                        path[strlen(dir)] = '/';
+                        strcpy(path + strlen(dir) + 1, subdir->name);
+
+                        DIR *icons = opendir(path);
+                        if (!icons) {
+                                free(path);
+                                continue;
+                        }
+
+                        struct dirent *direntry;
+                        while ((direntry = readdir(icons)) != NULL) {
+                                int len = strlen(direntry->d_name);
+                                if (len <= namelen + 2) { //must have some ext
+                                        continue;
+                                }
+                                if (strncmp(direntry->d_name, name, namelen) == 0) {
+                                        char *ext = direntry->d_name + namelen + 1;
+#ifdef WITH_GDK_PIXBUF
+                                        if (strcmp(ext, "png") == 0 ||
+                                                        strcmp(ext, "xpm") == 0 ||
+                                                        strcmp(ext, "svg") == 0) {
+#else
+                                        if (strcmp(ext, "png") == 0) {
+#endif
+                                                free(current_file);
+                                                char *icon_path = malloc(strlen(path) + len + 2);
+
+                                                strcpy(icon_path, path);
+                                                icon_path[strlen(path)] = '/';
+                                                strcpy(icon_path + strlen(path) + 1, direntry->d_name);
+                                                current_file = icon_path;
+                                                min_size_diff = size_diff;
+                                        }
+                                }
+                        }
+                        free(path);
+                        closedir(icons);
+                }
+                free_flat_list(subdirs);
+        }
+        free_flat_list(dirs);
+
+        return current_file;
+}
+
+cairo_surface_t *find_icon(const char *name, int size) {
+        char *image_path = find_icon_file(name, size);
+        if (image_path == NULL) {
+                return NULL;
+        }
+
+        cairo_surface_t *image = NULL;
+#ifdef WITH_GDK_PIXBUF
+        GError *err = NULL;
+        GdkPixbuf *pixbuf = gdk_pixbuf_new_from_file(image_path, &err);
+        if (!pixbuf) {
+                sway_log(L_ERROR, "Failed to load icon image: %s", err->message);
+        }
+        image = gdk_cairo_image_surface_create_from_pixbuf(pixbuf);
+        g_object_unref(pixbuf);
+#else
+        // TODO make svg work? cairo supports it. maybe remove gdk alltogether
+        image = cairo_image_surface_create_from_png(image_path);
+#endif //WITH_GDK_PIXBUF
+        if (!image) {
+                sway_log(L_ERROR, "Could not read icon image");
+                return NULL;
+        }
+
+        free(image_path);
+        return image;
+}
diff --git a/swaybar/tray/sni.c b/swaybar/tray/sni.c
new file mode 100644
index 00000000..f0638dca
--- /dev/null
+++ b/swaybar/tray/sni.c
@@ -0,0 +1,463 @@
+#define _XOPEN_SOURCE 500
+#include <stdlib.h>
+#include <stdio.h>
+#include <string.h>
+#include <stdint.h>
+#include <stdbool.h>
+#include <dbus/dbus.h>
+#include <arpa/inet.h>
+#include <netinet/in.h>
+#include "swaybar/tray/dbus.h"
+#include "swaybar/tray/sni.h"
+#include "swaybar/tray/icon.h"
+#include "swaybar/bar.h"
+#include "client/cairo.h"
+#include "log.h"
+
+// Not sure what this is but cairo needs it.
+static const cairo_user_data_key_t cairo_user_data_key;
+
+struct sni_icon_ref *sni_icon_ref_create(struct StatusNotifierItem *item,
+                int height) {
+        struct sni_icon_ref *sni_ref = malloc(sizeof(struct sni_icon_ref));
+        if (!sni_ref) {
+                return NULL;
+        }
+        sni_ref->icon = cairo_image_surface_scale(item->image, height, height);
+        sni_ref->ref = item;
+
+        return sni_ref;
+}
+
+void sni_icon_ref_free(struct sni_icon_ref *sni_ref) {
+        if (!sni_ref) {
+                return;
+        }
+        cairo_surface_destroy(sni_ref->icon);
+        free(sni_ref);
+}
+
+/* Gets the pixmap of an icon */
+static void reply_icon(DBusPendingCall *pending, void *_data) {
+        struct StatusNotifierItem *item = _data;
+
+        DBusMessage *reply = dbus_pending_call_steal_reply(pending);
+
+        if (!reply) {
+                sway_log(L_ERROR, "Did not get reply");
+                goto bail;
+        }
+
+        int message_type = dbus_message_get_type(reply);
+
+        if (message_type == DBUS_MESSAGE_TYPE_ERROR) {
+                char *msg;
+
+                dbus_message_get_args(reply, NULL,
+                                DBUS_TYPE_STRING, &msg,
+                                DBUS_TYPE_INVALID);
+
+                sway_log(L_ERROR, "Message is error: %s", msg);
+                goto bail;
+        }
+
+        DBusMessageIter iter;
+        DBusMessageIter variant; /* v[a(iiay)] */
+        DBusMessageIter array; /* a(iiay) */
+        DBusMessageIter d_struct; /* (iiay) */
+        DBusMessageIter icon; /* ay */
+
+        dbus_message_iter_init(reply, &iter);
+
+        // Each if here checks the types above before recursing
+        if (dbus_message_iter_get_arg_type(&iter) != DBUS_TYPE_VARIANT) {
+                sway_log(L_ERROR, "Relpy type incorrect");
+                sway_log(L_ERROR, "Should be \"v\", is \"%s\"",
+                                dbus_message_iter_get_signature(&iter));
+                goto bail;
+        }
+        dbus_message_iter_recurse(&iter, &variant);
+
+        if (strcmp("a(iiay)", dbus_message_iter_get_signature(&variant)) != 0) {
+                sway_log(L_ERROR, "Relpy type incorrect");
+                sway_log(L_ERROR, "Should be \"a(iiay)\", is \"%s\"",
+                                dbus_message_iter_get_signature(&variant));
+                goto bail;
+        }
+
+        if (dbus_message_iter_get_element_count(&variant) == 0) {
+                // Can't recurse if there are no items
+                sway_log(L_INFO, "Item has no icon");
+                goto bail;
+        }
+        dbus_message_iter_recurse(&variant, &array);
+
+        dbus_message_iter_recurse(&array, &d_struct);
+
+        int width;
+        dbus_message_iter_get_basic(&d_struct, &width);
+        dbus_message_iter_next(&d_struct);
+
+        int height;
+        dbus_message_iter_get_basic(&d_struct, &height);
+        dbus_message_iter_next(&d_struct);
+
+        int len = dbus_message_iter_get_element_count(&d_struct);
+
+        if (!len) {
+                sway_log(L_ERROR, "No icon data");
+                goto bail;
+        }
+
+        // Also implies len % 4 == 0, useful below
+        if (len != width * height * 4) {
+                sway_log(L_ERROR, "Incorrect array size passed");
+                goto bail;
+        }
+
+        dbus_message_iter_recurse(&d_struct, &icon);
+
+        int stride = cairo_format_stride_for_width(CAIRO_FORMAT_ARGB32, width);
+        // FIXME support a variable stride
+        // (works on my machine though for all tested widths)
+        if (!sway_assert(stride == width * 4, "Stride must be equal to byte length")) {
+                goto bail;
+        }
+
+        // Data is by reference, no need to free
+        uint8_t *message_data;
+        dbus_message_iter_get_fixed_array(&icon, &message_data, &len);
+
+        uint8_t *image_data = malloc(stride * height);
+        if (!image_data) {
+                sway_log(L_ERROR, "Could not allocate memory for icon");
+                goto bail;
+        }
+
+        // Transform from network byte order to host byte order
+        // Assumptions are safe because the equality above
+        uint32_t *network = (uint32_t *) message_data;
+        uint32_t *host = (uint32_t *)image_data;
+        for (int i = 0; i < width * height; ++i) {
+                host[i] = ntohl(network[i]);
+        }
+
+        cairo_surface_t *image = cairo_image_surface_create_for_data(
+                        image_data, CAIRO_FORMAT_ARGB32,
+                        width, height, stride);
+
+        if (image) {
+                if (item->image) {
+                        cairo_surface_destroy(item->image);
+                }
+                item->image = image;
+                // Free the image data on surface destruction
+                cairo_surface_set_user_data(image,
+                                &cairo_user_data_key,
+                                image_data,
+                                free);
+                item->dirty = true;
+                dirty = true;
+
+                dbus_message_unref(reply);
+                return;
+        } else {
+                sway_log(L_ERROR, "Could not create image surface");
+                free(image_data);
+        }
+
+bail:
+        if (reply) {
+                dbus_message_unref(reply);
+        }
+        sway_log(L_ERROR, "Could not get icon from item");
+        return;
+}
+static void send_icon_msg(struct StatusNotifierItem *item) {
+        DBusPendingCall *pending;
+        DBusMessage *message = dbus_message_new_method_call(
+                        item->name,
+                        "/StatusNotifierItem",
+                        "org.freedesktop.DBus.Properties",
+                        "Get");
+        const char *iface;
+        if (item->kde_special_snowflake) {
+                iface = "org.kde.StatusNotifierItem";
+        } else {
+                iface = "org.freedesktop.StatusNotifierItem";
+        }
+        const char *prop = "IconPixmap";
+
+        dbus_message_append_args(message,
+                        DBUS_TYPE_STRING, &iface,
+                        DBUS_TYPE_STRING, &prop,
+                        DBUS_TYPE_INVALID);
+
+        bool status =
+                dbus_connection_send_with_reply(conn, message, &pending, -1);
+
+        dbus_message_unref(message);
+
+        if (!(pending || status)) {
+                sway_log(L_ERROR, "Could not get item icon");
+                return;
+        }
+
+        dbus_pending_call_set_notify(pending, reply_icon, item, NULL);
+}
+
+/* Get an icon by its name */
+static void reply_icon_name(DBusPendingCall *pending, void *_data) {
+        struct StatusNotifierItem *item = _data;
+
+        DBusMessage *reply = dbus_pending_call_steal_reply(pending);
+
+        if (!reply) {
+                sway_log(L_INFO, "Got no icon name reply from item");
+                goto bail;
+        }
+
+        int message_type = dbus_message_get_type(reply);
+
+        if (message_type == DBUS_MESSAGE_TYPE_ERROR) {
+                char *msg;
+
+                dbus_message_get_args(reply, NULL,
+                                DBUS_TYPE_STRING, &msg,
+                                DBUS_TYPE_INVALID);
+
+                sway_log(L_INFO, "Could not get icon name: %s", msg);
+                goto bail;
+        }
+
+        DBusMessageIter iter; /* v[s] */
+        DBusMessageIter variant; /* s */
+
+        dbus_message_iter_init(reply, &iter);
+        if (dbus_message_iter_get_arg_type(&iter) != DBUS_TYPE_VARIANT) {
+                sway_log(L_ERROR, "Relpy type incorrect");
+                sway_log(L_ERROR, "Should be \"v\", is \"%s\"",
+                                dbus_message_iter_get_signature(&iter));
+                goto bail;
+        }
+        dbus_message_iter_recurse(&iter, &variant);
+
+
+        if (dbus_message_iter_get_arg_type(&variant) != DBUS_TYPE_STRING) {
+                sway_log(L_ERROR, "Relpy type incorrect");
+                sway_log(L_ERROR, "Should be \"s\", is \"%s\"",
+                                dbus_message_iter_get_signature(&iter));
+                goto bail;
+        }
+
+        char *icon_name;
+        dbus_message_iter_get_basic(&variant, &icon_name);
+
+        cairo_surface_t *image = find_icon(icon_name, 256);
+
+        if (image) {
+                sway_log(L_DEBUG, "Icon for %s found with size %d", icon_name,
+                                cairo_image_surface_get_width(image));
+                if (item->image) {
+                        cairo_surface_destroy(item->image);
+                }
+                item->image = image;
+                item->dirty = true;
+                dirty = true;
+
+                dbus_message_unref(reply);
+                return;
+        }
+
+bail:
+        if (reply) {
+                dbus_message_unref(reply);
+        }
+        // Now try the pixmap
+        send_icon_msg(item);
+        return;
+}
+static void send_icon_name_msg(struct StatusNotifierItem *item) {
+        DBusPendingCall *pending;
+        DBusMessage *message = dbus_message_new_method_call(
+                        item->name,
+                        "/StatusNotifierItem",
+                        "org.freedesktop.DBus.Properties",
+                        "Get");
+        const char *iface;
+        if (item->kde_special_snowflake) {
+                iface = "org.kde.StatusNotifierItem";
+        } else {
+                iface = "org.freedesktop.StatusNotifierItem";
+        }
+        const char *prop = "IconName";
+
+        dbus_message_append_args(message,
+                        DBUS_TYPE_STRING, &iface,
+                        DBUS_TYPE_STRING, &prop,
+                        DBUS_TYPE_INVALID);
+
+        bool status =
+                dbus_connection_send_with_reply(conn, message, &pending, -1);
+
+        dbus_message_unref(message);
+
+        if (!(pending || status)) {
+                sway_log(L_ERROR, "Could not get item icon name");
+                return;
+        }
+
+        dbus_pending_call_set_notify(pending, reply_icon_name, item, NULL);
+}
+
+void get_icon(struct StatusNotifierItem *item) {
+        send_icon_name_msg(item);
+}
+
+void sni_activate(struct StatusNotifierItem *item, uint32_t x, uint32_t y) {
+        const char *iface =
+                (item->kde_special_snowflake ? "org.kde.StatusNotifierItem"
+                 : "org.freedesktop.StatusNotifierItem");
+        DBusMessage *message = dbus_message_new_method_call(
+                        item->name,
+                        "/StatusNotifierItem",
+                        iface,
+                        "Activate");
+
+        dbus_message_append_args(message,
+                        DBUS_TYPE_INT32, &x,
+                        DBUS_TYPE_INT32, &y,
+                        DBUS_TYPE_INVALID);
+
+        dbus_connection_send(conn, message, NULL);
+
+        dbus_message_unref(message);
+}
+
+void sni_context_menu(struct StatusNotifierItem *item, uint32_t x, uint32_t y) {
+        const char *iface =
+                (item->kde_special_snowflake ? "org.kde.StatusNotifierItem"
+                 : "org.freedesktop.StatusNotifierItem");
+        DBusMessage *message = dbus_message_new_method_call(
+                        item->name,
+                        "/StatusNotifierItem",
+                        iface,
+                        "ContextMenu");
+
+        dbus_message_append_args(message,
+                        DBUS_TYPE_INT32, &x,
+                        DBUS_TYPE_INT32, &y,
+                        DBUS_TYPE_INVALID);
+
+        dbus_connection_send(conn, message, NULL);
+
+        dbus_message_unref(message);
+}
+void sni_secondary(struct StatusNotifierItem *item, uint32_t x, uint32_t y) {
+        const char *iface =
+                (item->kde_special_snowflake ? "org.kde.StatusNotifierItem"
+                 : "org.freedesktop.StatusNotifierItem");
+        DBusMessage *message = dbus_message_new_method_call(
+                        item->name,
+                        "/StatusNotifierItem",
+                        iface,
+                        "SecondaryActivate");
+
+        dbus_message_append_args(message,
+                        DBUS_TYPE_INT32, &x,
+                        DBUS_TYPE_INT32, &y,
+                        DBUS_TYPE_INVALID);
+
+        dbus_connection_send(conn, message, NULL);
+
+        dbus_message_unref(message);
+}
+
+static void get_unique_name(struct StatusNotifierItem *item) {
+        // I think that we're fine being sync here becaues the message is
+        // directly to the message bus. Could be async though.
+        DBusMessage *message = dbus_message_new_method_call(
+                        "org.freedesktop.DBus",
+                        "/org/freedesktop/DBus",
+                        "org.freedesktop.DBus",
+                        "GetNameOwner");
+
+        dbus_message_append_args(message,
+                        DBUS_TYPE_STRING, &item->name,
+                        DBUS_TYPE_INVALID);
+
+        DBusMessage *reply = dbus_connection_send_with_reply_and_block(
+                        conn, message, -1, NULL);
+
+        dbus_message_unref(message);
+
+        if (!reply) {
+                sway_log(L_ERROR, "Could not get unique name for item: %s",
+                                item->name);
+                return;
+        }
+
+        if (!dbus_message_get_args(reply, NULL,
+                                DBUS_TYPE_STRING, &item->unique_name,
+                                DBUS_TYPE_INVALID)) {
+                item->unique_name = NULL;
+                sway_log(L_ERROR, "Error parsing method args");
+        }
+
+        dbus_message_unref(reply);
+}
+
+struct StatusNotifierItem *sni_create(const char *name) {
+        struct StatusNotifierItem *item = malloc(sizeof(struct StatusNotifierItem));
+        item->name = strdup(name);
+        item->unique_name = NULL;
+        item->image = NULL;
+        item->dirty = false;
+
+        // If it doesn't use this name then assume that it uses the KDE spec
+        // This is because xembed-sni-proxy uses neither "org.freedesktop" nor
+        // "org.kde" and just gives us the items "unique name"
+        //
+        // We could use this to our advantage and fill out the "unique name"
+        // field with the given name if it is neither freedesktop or kde, but
+        // that's makes us rely on KDE hackyness which is bad practice
+        const char freedesktop_name[] = "org.freedesktop";
+        if (strncmp(name, freedesktop_name, sizeof(freedesktop_name) - 1) != 0) {
+                item->kde_special_snowflake = true;
+        } else {
+                item->kde_special_snowflake = false;
+        }
+
+        get_icon(item);
+
+        get_unique_name(item);
+
+        return item;
+}
+/* Return true if `item` has a name of `str` */
+int sni_str_cmp(const void *_item, const void *_str) {
+        const struct StatusNotifierItem *item = _item;
+        const char *str = _str;
+
+        return strcmp(item->name, str);
+}
+/* Returns true if `item` has a unique name of `str` */
+int sni_uniq_cmp(const void *_item, const void *_str) {
+        const struct StatusNotifierItem *item = _item;
+        const char *str = _str;
+
+        if (!item->unique_name) {
+                return false;
+        }
+        return strcmp(item->unique_name, str);
+}
+void sni_free(struct StatusNotifierItem *item) {
+        if (!item) {
+                return;
+        }
+        free(item->name);
+        if (item->image) {
+                cairo_surface_destroy(item->image);
+        }
+        free(item);
+}
diff --git a/swaybar/tray/sni_watcher.c b/swaybar/tray/sni_watcher.c
new file mode 100644
index 00000000..388e181d
--- /dev/null
+++ b/swaybar/tray/sni_watcher.c
@@ -0,0 +1,487 @@
+#define _XOPEN_SOURCE 500
+#include <unistd.h>
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+#include <stdbool.h>
+#include <dbus/dbus.h>
+#include "swaybar/tray/dbus.h"
+#include "list.h"
+#include "log.h"
+
+static list_t *items = NULL;
+static list_t *hosts = NULL;
+
+/**
+ * Describes the function of the StatusNotifierWatcher
+ * See https://freedesktop.org/wiki/Specifications/StatusNotifierItem/StatusNotifierWatcher/
+ *
+ * We also implement KDE's special snowflake protocol, it's like this but with
+ * all occurrences 'freedesktop' replaced with 'kde'. There is no KDE introspect.
+ */
+static const char *interface_xml =
+        "<!DOCTYPE node PUBLIC '-//freedesktop//DTD D-BUS Object Introspection 1.0//EN'"
+        "'http://www.freedesktop.org/standards/dbus/1.0/introspect.dtd'>"
+        "<node>"
+        "  <interface name='org.freedesktop.DBus.Introspectable'>"
+        "    <method name='Introspect'>"
+        "       <arg name='xml_data' direction='out' type='s'/>"
+        "    </method>"
+        "  </interface>"
+        "  <interface name='org.freedesktop.DBus.Properties'>"
+        "    <method name='Get'>"
+        "       <arg name='interface' direction='in' type='s'/>"
+        "       <arg name='propname' direction='in' type='s'/>"
+        "       <arg name='value' direction='out' type='v'/>"
+        "    </method>"
+        "    <method name='Set'>"
+        "       <arg name='interface' direction='in' type='s'/>"
+        "       <arg name='propname' direction='in' type='s'/>"
+        "       <arg name='value' direction='in' type='v'/>"
+        "    </method>"
+        "    <method name='GetAll'>"
+        "       <arg name='interface' direction='in' type='s'/>"
+        "       <arg name='props' direction='out' type='a{sv}'/>"
+        "    </method>"
+        "  </interface>"
+        "  <interface name='org.freedesktop.StatusNotifierWatcher'>"
+        "    <method name='RegisterStatusNotifierItem'>"
+        "      <arg type='s' name='service' direction='in'/>"
+        "    </method>"
+        "    <method name='RegisterStatusNotifierHost'>"
+        "      <arg type='s' name='service' direction='in'/>"
+        "    </method>"
+        "    <property name='RegisteredStatusNotifierItems' type='as' access='read'/>"
+        "    <property name='IsStatusNotifierHostRegistered' type='b' access='read'/>"
+        "    <property name='ProtocolVersion' type='i' access='read'/>"
+        "    <signal name='StatusNotifierItemRegistered'>"
+        "      <arg type='s' name='service' direction='out'/>"
+        "    </signal>"
+        "    <signal name='StatusNotifierItemUnregistered'>"
+        "      <arg type='s' name='service' direction='out'/>"
+        "    </signal>"
+        "    <signal name='StatusNotifierHostRegistered'>"
+        "      <arg type='' name='service' direction='out'/>"
+        "    </signal>"
+        "  </interface>"
+        "</node>";
+
+static void host_registered_signal(DBusConnection *connection) {
+        // Send one signal for each protocol
+        DBusMessage *signal = dbus_message_new_signal(
+                        "/StatusNotifierWatcher",
+                        "org.freedesktop.StatusNotifierWatcher",
+                        "StatusNotifierHostRegistered");
+
+        dbus_connection_send(connection, signal, NULL);
+        dbus_message_unref(signal);
+
+
+        signal = dbus_message_new_signal(
+                        "/StatusNotifierWatcher",
+                        "org.kde.StatusNotifierWatcher",
+                        "StatusNotifierHostRegistered");
+
+        dbus_connection_send(connection, signal, NULL);
+        dbus_message_unref(signal);
+}
+static void item_registered_signal(DBusConnection *connection, const char *name) {
+        DBusMessage *signal = dbus_message_new_signal(
+                        "/StatusNotifierWatcher",
+                        "org.freedesktop.StatusNotifierWatcher",
+                        "StatusNotifierItemRegistered");
+        dbus_message_append_args(signal,
+                        DBUS_TYPE_STRING, &name,
+                        DBUS_TYPE_INVALID);
+        dbus_connection_send(connection, signal, NULL);
+        dbus_message_unref(signal);
+
+        signal = dbus_message_new_signal(
+                        "/StatusNotifierWatcher",
+                        "org.kde.StatusNotifierWatcher",
+                        "StatusNotifierItemRegistered");
+        dbus_message_append_args(signal,
+                        DBUS_TYPE_STRING, &name,
+                        DBUS_TYPE_INVALID);
+        dbus_connection_send(connection, signal, NULL);
+        dbus_message_unref(signal);
+}
+static void item_unregistered_signal(DBusConnection *connection, const char *name) {
+        DBusMessage *signal = dbus_message_new_signal(
+                        "/StatusNotifierWatcher",
+                        "org.freedesktop.StatusNotifierWatcher",
+                        "StatusNotifierItemUnregistered");
+        dbus_message_append_args(signal,
+                        DBUS_TYPE_STRING, &name,
+                        DBUS_TYPE_INVALID);
+        dbus_connection_send(connection, signal, NULL);
+        dbus_message_unref(signal);
+
+        signal = dbus_message_new_signal(
+                        "/StatusNotifierWatcher",
+                        "org.kde.StatusNotifierWatcher",
+                        "StatusNotifierItemUnregistered");
+        dbus_message_append_args(signal,
+                        DBUS_TYPE_STRING, &name,
+                        DBUS_TYPE_INVALID);
+        dbus_connection_send(connection, signal, NULL);
+        dbus_message_unref(signal);
+}
+
+static void respond_to_introspect(DBusConnection *connection, DBusMessage *request) {
+        DBusMessage *reply;
+
+        reply = dbus_message_new_method_return(request);
+        dbus_message_append_args(reply,
+                        DBUS_TYPE_STRING, &interface_xml,
+                        DBUS_TYPE_INVALID);
+        dbus_connection_send(connection, reply, NULL);
+        dbus_message_unref(reply);
+}
+
+static void register_item(DBusConnection *connection, DBusMessage *message) {
+        DBusError error;
+        char *name;
+
+        dbus_error_init(&error);
+        if (!dbus_message_get_args(message, &error,
+                                DBUS_TYPE_STRING, &name,
+                                DBUS_TYPE_INVALID)) {
+                sway_log(L_ERROR, "Error parsing method args: %s\n", error.message);
+        }
+
+        name = strdup(name);
+        sway_log(L_INFO, "RegisterStatusNotifierItem called with \"%s\"\n", name);
+
+        // Don't add duplicate or not real item
+        if (list_seq_find(items, (int (*)(const void *, const void *))strcmp, name) != -1) {
+                return;
+        }
+        if (!dbus_bus_name_has_owner(connection, name, &error)) {
+                return;
+        }
+
+        list_add(items, name);
+        item_registered_signal(connection, name);
+
+        // It's silly, but xembedsniproxy wants a reply for this function
+        DBusMessage *reply = dbus_message_new_method_return(message);
+        dbus_connection_send(connection, reply, NULL);
+        dbus_message_unref(reply);
+}
+
+static void register_host(DBusConnection *connection, DBusMessage *message) {
+        DBusError error;
+        char *name;
+
+        dbus_error_init(&error);
+        if (!dbus_message_get_args(message, &error,
+                                DBUS_TYPE_STRING, &name,
+                                DBUS_TYPE_INVALID)) {
+                sway_log(L_ERROR, "Error parsing method args: %s\n", error.message);
+        }
+
+        sway_log(L_INFO, "RegisterStatusNotifierHost called with \"%s\"\n", name);
+
+        // Don't add duplicate or not real host
+        if (list_seq_find(hosts, (int (*)(const void *, const void *))strcmp, name) != -1) {
+                return;
+        }
+        if (!dbus_bus_name_has_owner(connection, name, &error)) {
+                return;
+        }
+
+        list_add(hosts, strdup(name));
+        host_registered_signal(connection);
+}
+
+static void get_property(DBusConnection *connection, DBusMessage *message) {
+        DBusError error;
+        char *interface;
+        char *property;
+
+        dbus_error_init(&error);
+        if (!dbus_message_get_args(message, &error,
+                                DBUS_TYPE_STRING, &interface,
+                                DBUS_TYPE_STRING, &property,
+                                DBUS_TYPE_INVALID)) {
+                sway_log(L_ERROR, "Error parsing prop args: %s\n", error.message);
+                return;
+        }
+
+        if (strcmp(property, "RegisteredStatusNotifierItems") == 0) {
+                sway_log(L_INFO, "Replying with items\n");
+                DBusMessage *reply;
+                reply = dbus_message_new_method_return(message);
+                DBusMessageIter iter;
+                DBusMessageIter sub;
+                DBusMessageIter subsub;
+
+                dbus_message_iter_init_append(reply, &iter);
+
+                dbus_message_iter_open_container(&iter, DBUS_TYPE_VARIANT,
+                                "as", &sub);
+                dbus_message_iter_open_container(&sub, DBUS_TYPE_ARRAY,
+                                "s", &subsub);
+
+                for (int i = 0; i < items->length; ++i) {
+                        dbus_message_iter_append_basic(&subsub,
+                                        DBUS_TYPE_STRING, &items->items[i]);
+                }
+
+                dbus_message_iter_close_container(&sub, &subsub);
+                dbus_message_iter_close_container(&iter, &sub);
+
+                dbus_connection_send(connection, reply, NULL);
+                dbus_message_unref(reply);
+        } else if (strcmp(property, "IsStatusNotifierHostRegistered") == 0) {
+                DBusMessage *reply;
+                DBusMessageIter iter;
+                DBusMessageIter sub;
+                int registered = (hosts == NULL || hosts->length == 0) ? 0 : 1;
+
+                reply = dbus_message_new_method_return(message);
+
+                dbus_message_iter_init_append(reply, &iter);
+
+                dbus_message_iter_open_container(&iter, DBUS_TYPE_VARIANT,
+                                "b", &sub);
+                dbus_message_iter_append_basic(&sub,
+                                DBUS_TYPE_BOOLEAN, &registered);
+
+                dbus_message_iter_close_container(&iter, &sub);
+
+                dbus_connection_send(connection, reply, NULL);
+                dbus_message_unref(reply);
+        } else if (strcmp(property, "ProtocolVersion") == 0) {
+                DBusMessage *reply;
+                DBusMessageIter iter;
+                DBusMessageIter sub;
+                const int version = 0;
+
+                reply = dbus_message_new_method_return(message);
+
+                dbus_message_iter_init_append(reply, &iter);
+
+                dbus_message_iter_open_container(&iter, DBUS_TYPE_VARIANT,
+                                "i", &sub);
+                dbus_message_iter_append_basic(&sub,
+                                DBUS_TYPE_INT32, &version);
+
+                dbus_message_iter_close_container(&iter, &sub);
+                dbus_connection_send(connection, reply, NULL);
+                dbus_message_unref(reply);
+        }
+}
+
+static void set_property(DBusConnection *connection, DBusMessage *message) {
+        // All properties are read only and we don't allow new properties
+        return;
+}
+
+static void get_all(DBusConnection *connection, DBusMessage *message) {
+        DBusMessage *reply;
+        reply = dbus_message_new_method_return(message);
+        DBusMessageIter iter; /* a{v} */
+        DBusMessageIter arr;
+        DBusMessageIter dict;
+        DBusMessageIter sub;
+        DBusMessageIter subsub;
+        int registered = (hosts == NULL || hosts->length == 0) ? 0 : 1;
+        const int version = 0;
+        const char *prop;
+
+        // Could clean this up with a function for each prop
+        dbus_message_iter_init_append(reply, &iter);
+        dbus_message_iter_open_container(&iter, DBUS_TYPE_ARRAY,
+                        "{sv}", &arr);
+
+        prop = "RegisteredStatusNotifierItems";
+        dbus_message_iter_open_container(&arr, DBUS_TYPE_DICT_ENTRY,
+                        NULL, &dict);
+        dbus_message_iter_append_basic(&dict,
+                        DBUS_TYPE_STRING, &prop);
+        dbus_message_iter_open_container(&dict, DBUS_TYPE_VARIANT,
+                        "as", &sub);
+        dbus_message_iter_open_container(&sub, DBUS_TYPE_ARRAY,
+                        "s", &subsub);
+        for (int i = 0; i < items->length; ++i) {
+                dbus_message_iter_append_basic(&subsub,
+                                DBUS_TYPE_STRING, &items->items[i]);
+        }
+        dbus_message_iter_close_container(&sub, &subsub);
+        dbus_message_iter_close_container(&dict, &sub);
+        dbus_message_iter_close_container(&arr, &dict);
+
+        prop = "IsStatusNotifierHostRegistered";
+        dbus_message_iter_open_container(&arr, DBUS_TYPE_DICT_ENTRY,
+                        NULL, &dict);
+        dbus_message_iter_append_basic(&dict,
+                        DBUS_TYPE_STRING, &prop);
+        dbus_message_iter_open_container(&dict, DBUS_TYPE_VARIANT,
+                        "b", &sub);
+        dbus_message_iter_append_basic(&sub,
+                        DBUS_TYPE_BOOLEAN, &registered);
+        dbus_message_iter_close_container(&dict, &sub);
+        dbus_message_iter_close_container(&arr, &dict);
+
+        prop = "ProtocolVersion";
+        dbus_message_iter_open_container(&arr, DBUS_TYPE_DICT_ENTRY,
+                        NULL, &dict);
+        dbus_message_iter_append_basic(&dict,
+                        DBUS_TYPE_STRING, &prop);
+        dbus_message_iter_open_container(&dict, DBUS_TYPE_VARIANT,
+                        "i", &sub);
+        dbus_message_iter_append_basic(&sub,
+                        DBUS_TYPE_INT32, &version);
+        dbus_message_iter_close_container(&dict, &sub);
+        dbus_message_iter_close_container(&arr, &dict);
+
+        dbus_message_iter_close_container(&iter, &arr);
+
+        dbus_connection_send(connection, reply, NULL);
+        dbus_message_unref(reply);
+}
+
+static DBusHandlerResult message_handler(DBusConnection *connection, 
+                DBusMessage *message, void *data) {
+        const char *interface_name = dbus_message_get_interface(message);
+        const char *member_name = dbus_message_get_member(message);
+
+        // In order of the xml above
+        if (strcmp(interface_name, "org.freedesktop.DBus.Introspectable") == 0 &&
+                        strcmp(member_name, "Introspect") == 0) {
+                // We don't have an introspect for KDE
+                respond_to_introspect(connection, message);
+                return DBUS_HANDLER_RESULT_HANDLED;
+        } else if (strcmp(interface_name, "org.freedesktop.DBus.Properties") == 0) {
+                if (strcmp(member_name, "Get") == 0) {
+                        get_property(connection, message);
+                        return DBUS_HANDLER_RESULT_HANDLED;
+                } else if (strcmp(member_name, "Set") == 0) {
+                        set_property(connection, message);
+                        return DBUS_HANDLER_RESULT_HANDLED;
+                } else if (strcmp(member_name, "GetAll") == 0) {
+                        get_all(connection, message);
+                        return DBUS_HANDLER_RESULT_HANDLED;
+                } else {
+                        return DBUS_HANDLER_RESULT_NOT_YET_HANDLED;
+                }
+        } else if (strcmp(interface_name, "org.freedesktop.StatusNotifierWatcher") == 0 ||
+                        strcmp(interface_name, "org.kde.StatusNotifierWatcher") == 0) {
+                if (strcmp(member_name, "RegisterStatusNotifierItem") == 0) {
+                        register_item(connection, message);
+                        return DBUS_HANDLER_RESULT_HANDLED;
+                } else if (strcmp(member_name, "RegisterStatusNotifierHost") == 0) {
+                        register_host(connection, message);
+                        return DBUS_HANDLER_RESULT_HANDLED;
+                } else {
+                        return DBUS_HANDLER_RESULT_NOT_YET_HANDLED;
+                }
+        }
+        return DBUS_HANDLER_RESULT_NOT_YET_HANDLED;
+}
+
+static DBusHandlerResult signal_handler(DBusConnection *connection,
+                DBusMessage *message, void *_data) {
+        if (dbus_message_is_signal(message, "org.freedesktop.DBus", "NameOwnerChanged")) {
+                // Only eat the message if it is name that we are watching
+                const char *name;
+                const char *old_owner;
+                const char *new_owner;
+                int index;
+                if (!dbus_message_get_args(message, NULL,
+                                DBUS_TYPE_STRING, &name,
+                                DBUS_TYPE_STRING, &old_owner,
+                                DBUS_TYPE_STRING, &new_owner,
+                                DBUS_TYPE_INVALID)) {
+                        sway_log(L_ERROR, "Error getting LostName args");
+                        return DBUS_HANDLER_RESULT_NOT_YET_HANDLED;
+                }
+                if (strcmp(new_owner, "") != 0) {
+                        // Name is not lost
+                        return DBUS_HANDLER_RESULT_NOT_YET_HANDLED;
+                }
+                if ((index = list_seq_find(items, (int (*)(const void *, const void *))strcmp, name)) != -1) {
+                        sway_log(L_INFO, "Status Notifier Item lost %s", name);
+                        free(items->items[index]);
+                        list_del(items, index);
+                        item_unregistered_signal(connection, name);
+
+                        return DBUS_HANDLER_RESULT_HANDLED;
+                }
+                if ((index = list_seq_find(hosts, (int (*)(const void *, const void *))strcmp, name)) != -1) {
+                        sway_log(L_INFO, "Status Notifier Host lost %s", name);
+                        free(hosts->items[index]);
+                        list_del(hosts, index);
+
+                        return DBUS_HANDLER_RESULT_HANDLED;
+                }
+        }
+        return DBUS_HANDLER_RESULT_NOT_YET_HANDLED;
+}
+
+static const DBusObjectPathVTable vtable = {
+        .message_function = message_handler,
+        .unregister_function = NULL,
+};
+
+int init_sni_watcher() {
+        DBusError error;
+        dbus_error_init(&error);
+        if (!conn) {
+                sway_log(L_ERROR, "Connection is null, cannot initiate StatusNotifierWatcher");
+                return -1;
+        }
+
+        items = create_list();
+        hosts = create_list();
+
+        int status = dbus_bus_request_name(conn, "org.freedesktop.StatusNotifierWatcher",
+                        DBUS_NAME_FLAG_REPLACE_EXISTING,
+                        &error);
+        if (status == DBUS_REQUEST_NAME_REPLY_PRIMARY_OWNER) {
+                sway_log(L_DEBUG, "Got watcher name");
+        } else if (status == DBUS_REQUEST_NAME_REPLY_IN_QUEUE) {
+                sway_log(L_INFO, "Could not get watcher name, it may start later");
+        }
+        if (dbus_error_is_set(&error)) {
+                sway_log(L_ERROR, "dbus err getting watcher name: %s\n", error.message);
+                return -1;
+        }
+
+        status = dbus_bus_request_name(conn, "org.kde.StatusNotifierWatcher",
+                        DBUS_NAME_FLAG_REPLACE_EXISTING,
+                        &error);
+        if (status == DBUS_REQUEST_NAME_REPLY_PRIMARY_OWNER) {
+                sway_log(L_DEBUG, "Got kde watcher name");
+        } else if (status == DBUS_REQUEST_NAME_REPLY_IN_QUEUE) {
+                sway_log(L_INFO, "Could not get kde watcher name, it may start later");
+        }
+        if (dbus_error_is_set(&error)) {
+                sway_log(L_ERROR, "dbus err getting kde watcher name: %s\n", error.message);
+                return -1;
+        }
+
+        dbus_connection_try_register_object_path(conn,
+                        "/StatusNotifierWatcher",
+                        &vtable, NULL, &error);
+        if (dbus_error_is_set(&error)) {
+                sway_log(L_ERROR, "dbus_err: %s\n", error.message);
+                return -1;
+        }
+
+        dbus_bus_add_match(conn,
+                        "type='signal',\
+                        sender='org.freedesktop.DBus',\
+                        interface='org.freedesktop.DBus',\
+                        member='NameOwnerChanged'",
+                        &error);
+
+        if (dbus_error_is_set(&error)) {
+                sway_log(L_ERROR, "DBus error getting match args: %s", error.message);
+        }
+
+        dbus_connection_add_filter(conn, signal_handler, NULL, NULL);
+        return 0;
+}
diff --git a/swaybar/tray/tray.c b/swaybar/tray/tray.c
new file mode 100644
index 00000000..9a709fe4
--- /dev/null
+++ b/swaybar/tray/tray.c
@@ -0,0 +1,279 @@
+#define _XOPEN_SOURCE 500
+#include <unistd.h>
+#include <stdlib.h>
+#include <string.h>
+#include <dbus/dbus.h>
+#include "swaybar/bar.h"
+#include "swaybar/tray/tray.h"
+#include "swaybar/tray/dbus.h"
+#include "swaybar/tray/sni.h"
+#include "swaybar/bar.h"
+#include "list.h"
+#include "log.h"
+
+struct tray *tray;
+
+static void register_host(char *name) {
+        DBusMessage *message;
+
+        message = dbus_message_new_method_call(
+                        "org.freedesktop.StatusNotifierWatcher",
+                        "/StatusNotifierWatcher",
+                        "org.freedesktop.StatusNotifierWatcher",
+                        "RegisterStatusNotifierHost");
+        if (!message) {
+                sway_log(L_ERROR, "Cannot allocate dbus method call");
+                return;
+        }
+
+        dbus_message_append_args(message,
+                        DBUS_TYPE_STRING, &name,
+                        DBUS_TYPE_INVALID);
+
+        dbus_connection_send(conn, message, NULL);
+
+        dbus_message_unref(message);
+}
+
+static void get_items_reply(DBusPendingCall *pending, void *_data) {
+        DBusMessage *reply = dbus_pending_call_steal_reply(pending);
+
+        if (!reply) {
+                sway_log(L_ERROR, "Got no items reply from sni watcher");
+                goto bail;
+        }
+
+        int message_type = dbus_message_get_type(reply);
+
+        if (message_type == DBUS_MESSAGE_TYPE_ERROR) {
+                char *msg;
+
+                dbus_message_get_args(reply, NULL,
+                                DBUS_TYPE_STRING, &msg,
+                                DBUS_TYPE_INVALID);
+
+                sway_log(L_ERROR, "Message is error: %s", msg);
+                goto bail;
+        }
+
+        DBusMessageIter iter;
+        DBusMessageIter variant;
+        DBusMessageIter array;
+
+        dbus_message_iter_init(reply, &iter);
+        if (dbus_message_iter_get_arg_type(&iter) != DBUS_TYPE_VARIANT) {
+                sway_log(L_ERROR, "Replyed with wrong type, not v(as)");
+                goto bail;
+        }
+        dbus_message_iter_recurse(&iter, &variant);
+        if (dbus_message_iter_get_arg_type(&variant) != DBUS_TYPE_ARRAY ||
+                        dbus_message_iter_get_element_type(&variant) != DBUS_TYPE_STRING) {
+                sway_log(L_ERROR, "Replyed with wrong type, not v(as)");
+                goto bail;
+        }
+
+        // Clear list
+        list_foreach(tray->items, (void (*)(void *))sni_free);
+        list_free(tray->items);
+        tray->items = create_list();
+
+        // O(n) function, could be faster dynamically reading values
+        int len = dbus_message_iter_get_element_count(&variant);
+
+        dbus_message_iter_recurse(&variant, &array);
+        for (int i = 0; i < len; i++) {
+                const char *name;
+                dbus_message_iter_get_basic(&array, &name);
+
+                struct StatusNotifierItem *item = sni_create(name);
+
+                sway_log(L_DEBUG, "Item registered with host: %s", name);
+                list_add(tray->items, item);
+                dirty = true;
+        }
+
+bail:
+        dbus_message_unref(reply);
+        return;
+}
+static void get_items() {
+        DBusPendingCall *pending;
+        DBusMessage *message = dbus_message_new_method_call(
+                        "org.freedesktop.StatusNotifierWatcher",
+                        "/StatusNotifierWatcher",
+                        "org.freedesktop.DBus.Properties",
+                        "Get");
+
+        const char *iface = "org.freedesktop.StatusNotifierWatcher";
+        const char *prop = "RegisteredStatusNotifierItems";
+        dbus_message_append_args(message,
+                        DBUS_TYPE_STRING, &iface,
+                        DBUS_TYPE_STRING, &prop,
+                        DBUS_TYPE_INVALID);
+
+        bool status =
+                dbus_connection_send_with_reply(conn, message, &pending, -1);
+        dbus_message_unref(message);
+
+        if (!(pending || status)) {
+                sway_log(L_ERROR, "Could not get items");
+                return;
+        }
+
+        dbus_pending_call_set_notify(pending, get_items_reply, NULL, NULL);
+}
+
+static DBusHandlerResult signal_handler(DBusConnection *connection,
+                DBusMessage *message, void *_data) {
+        if (dbus_message_is_signal(message, "org.freedesktop.StatusNotifierWatcher",
+                                "StatusNotifierItemRegistered")) {
+                const char *name;
+                if (!dbus_message_get_args(message, NULL,
+                                DBUS_TYPE_STRING, &name,
+                                DBUS_TYPE_INVALID)) {
+                        sway_log(L_ERROR, "Error getting StatusNotifierItemRegistered args");
+                        return DBUS_HANDLER_RESULT_NOT_YET_HANDLED;
+                }
+
+                if (list_seq_find(tray->items, sni_str_cmp, name) == -1) {
+                        struct StatusNotifierItem *item = sni_create(name);
+
+                        list_add(tray->items, item);
+                        dirty = true;
+                }
+
+                return DBUS_HANDLER_RESULT_HANDLED;
+        } else if (dbus_message_is_signal(message, "org.freedesktop.StatusNotifierWatcher",
+                                "StatusNotifierItemUnregistered")) {
+                const char *name;
+                if (!dbus_message_get_args(message, NULL,
+                                DBUS_TYPE_STRING, &name,
+                                DBUS_TYPE_INVALID)) {
+                        sway_log(L_ERROR, "Error getting StatusNotifierItemUnregistered args");
+                        return DBUS_HANDLER_RESULT_NOT_YET_HANDLED;
+                }
+
+                int index;
+                if ((index = list_seq_find(tray->items, sni_str_cmp, name)) != -1) {
+                        sni_free(tray->items->items[index]);
+                        list_del(tray->items, index);
+                        dirty = true;
+                } else {
+                        // If it's not in our list, then our list is incorrect.
+                        // Fetch all items again
+                        sway_log(L_INFO, "Host item list incorrect, refreshing");
+                        get_items();
+                }
+
+                return DBUS_HANDLER_RESULT_HANDLED;
+        } else if (dbus_message_is_signal(message, "org.freedesktop.StatusNotifierItem",
+                                "NewIcon") || dbus_message_is_signal(message,
+                                "org.kde.StatusNotifierItem", "NewIcon")) {
+                const char *name;
+                int index;
+                struct StatusNotifierItem *item;
+
+                name = dbus_message_get_sender(message);
+                if ((index = list_seq_find(tray->items, sni_uniq_cmp, name)) != -1) {
+                        item = tray->items->items[index];
+                        get_icon(item);
+                }
+
+                return DBUS_HANDLER_RESULT_HANDLED;
+        }
+        return DBUS_HANDLER_RESULT_NOT_YET_HANDLED;
+}
+
+int init_tray() {
+        tray = (struct tray *)malloc(sizeof(tray));
+
+        tray->items = create_list();
+
+        DBusError error;
+        dbus_error_init(&error);
+        char *name = NULL;
+        if (!conn) {
+                sway_log(L_ERROR, "Connection is null, cannot init SNI host");
+                goto err;
+        }
+        name = calloc(sizeof(char), 256);
+
+        if (!name) {
+                sway_log(L_ERROR, "Cannot allocate name");
+                goto err;
+        }
+
+        pid_t pid = getpid();
+        if (snprintf(name, 256, "org.freedesktop.StatusNotifierHost-%d", pid)
+                        >= 256) {
+                sway_log(L_ERROR, "Cannot get host name because string is too short."
+                                "This should not happen");
+                goto err;
+        }
+
+        // We want to be the sole owner of this name
+        if (dbus_bus_request_name(conn, name, DBUS_NAME_FLAG_DO_NOT_QUEUE,
+                        &error) != DBUS_REQUEST_NAME_REPLY_PRIMARY_OWNER) {
+                sway_log(L_ERROR, "Cannot get host name and start the tray");
+                goto err;
+        }
+        if (dbus_error_is_set(&error)) {
+                sway_log(L_ERROR, "Dbus err getting host name: %s\n", error.message);
+                goto err;
+        }
+        sway_log(L_DEBUG, "Got host name");
+
+        register_host(name);
+
+        get_items();
+
+        // Perhaps use addmatch helper functions like wlc does?
+        dbus_bus_add_match(conn,
+                        "type='signal',\
+                        sender='org.freedesktop.StatusNotifierWatcher',\
+                        member='StatusNotifierItemRegistered'",
+                        &error);
+        if (dbus_error_is_set(&error)) {
+                sway_log(L_ERROR, "dbus_err: %s", error.message);
+                goto err;
+        }
+        dbus_bus_add_match(conn,
+                        "type='signal',\
+                        sender='org.freedesktop.StatusNotifierWatcher',\
+                        member='StatusNotifierItemUnregistered'",
+                        &error);
+        if (dbus_error_is_set(&error)) {
+                sway_log(L_ERROR, "dbus_err: %s", error.message);
+                return -1;
+        }
+
+        // SNI matches
+        dbus_bus_add_match(conn,
+                        "type='signal',\
+                        interface='org.freedesktop.StatusNotifierItem',\
+                        member='NewIcon'",
+                        &error);
+        if (dbus_error_is_set(&error)) {
+                sway_log(L_ERROR, "dbus_err %s", error.message);
+                goto err;
+        }
+        dbus_bus_add_match(conn,
+                        "type='signal',\
+                        interface='org.kde.StatusNotifierItem',\
+                        member='NewIcon'",
+                        &error);
+        if (dbus_error_is_set(&error)) {
+                sway_log(L_ERROR, "dbus_err %s", error.message);
+                goto err;
+        }
+
+        dbus_connection_add_filter(conn, signal_handler, NULL, NULL);
+
+        free(name);
+        return 0;
+
+err:
+        // TODO better handle errors
+        free(name);
+        return -1;
+}