config: add toplevel-tag=TAG

Add support for the new xdg-toplevel-tag-v1 Wayland protocol, by
exposing a new config option, `toplevel-tag`, and a corresponding
command option, `--toplevel-tag` (in both `foot` and `footclient`).

This can help the compositor with session management, or custom window
rules.

Closes #2212

CHANGELOG.md

@@ -69,6 +69,15 @@
 
 ## Unreleased
 ### Added
+
+* `toplevel-tag` option (and `--toplevel-tag` command line options to
+  `foot` and `footclient`), allowing you to set a custom toplevel
+  tag. The compositor must implement the new `xdg-toplevel-tag-v1`
+  Wayland protocol ([#2212][2212]).
+
+[2212]: https://codeberg.org/dnkl/foot/issues/2212
+
+
 ### Changed
 
 * When enabling _"focus mode"_ (private mode 1004), foot now sends a

client.c

@@ -76,6 +76,7 @@ print_usage(const char *prog_name)
         "  -t,--term=TERM                           value to set the environment variable TERM to (" FOOT_DEFAULT_TERM ")\n"
         "  -T,--title=TITLE                         initial window title (foot)\n"
         "  -a,--app-id=ID                           window application ID (foot)\n"
+        "     --toplevel-tag=TAG                    set a custom toplevel tag\n"
         "  -w,--window-size-pixels=WIDTHxHEIGHT     initial width and height, in pixels\n"
         "  -W,--window-size-chars=WIDTHxHEIGHT      initial width and height, in characters\n"
         "  -m,--maximized                           start in maximized mode\n"
@@ -137,6 +138,10 @@ send_string_list(int fd, const string_list_t *string_list)
     return true;
 }
 
+enum {
+    TOPLEVEL_TAG_OPTION = CHAR_MAX + 1,
+};
+
 int
 main(int argc, char *const *argv)
 {
@@ -151,6 +156,7 @@ main(int argc, char *const *argv)
         {"term",               required_argument, NULL, 't'},
         {"title",              required_argument, NULL, 'T'},
         {"app-id",             required_argument, NULL, 'a'},
+        {"toplevel-tag",       required_argument, NULL, TOPLEVEL_TAG_OPTION},
         {"window-size-pixels", required_argument, NULL, 'w'},
         {"window-size-chars",  required_argument, NULL, 'W'},
         {"maximized",          no_argument,       NULL, 'm'},
@@ -220,6 +226,12 @@ main(int argc, char *const *argv)
                 goto err;
             break;
 
+        case TOPLEVEL_TAG_OPTION:
+            snprintf(buf, sizeof(buf), "toplevel-tag=%s", optarg);
+            if (!push_string(&overrides, buf, &total_len))
+                goto err;
+            break;
+
         case 'L':
             if (!push_string(&overrides, "login-shell=yes", &total_len))
                 goto err;

completions/bash/foot

@@ -6,6 +6,7 @@ _foot()
     local cur prev flags word commands match previous_words i offset
     flags=(
         "--app-id"
+        "--toplevel-tag"
         "--check-config"
         "--config"
         "--font"
@@ -40,7 +41,7 @@ _foot()
     for word in "${previous_words[@]}" ; do
         match=$(printf "$commands" | grep -Fx "$word" 2>/dev/null)
         if [[ ! -z "$match" ]] ; then
-            if [[ ${COMP_WORDS[i-1]} =~ ^(--app-id|--config|--font|--log-level|--pty|--term|--title|--window-size-pixels|--window-size-chars|--working-directory)$ ]] ; then
+            if [[ ${COMP_WORDS[i-1]} =~ ^(--app-id|--toplevel-tag|--config|--font|--log-level|--pty|--term|--title|--window-size-pixels|--window-size-chars|--working-directory)$ ]] ; then
                 (( i++ ))
                 continue
             fi
@@ -75,7 +76,7 @@ _foot()
         COMPREPLY=( $(compgen -W "none error warning info" -- ${cur}) ) ;;
     --log-colorize|-l)
         COMPREPLY=( $(compgen -W "never always auto" -- ${cur}) ) ;;
-    --app-id|--help|--override|--pty|--title|--version|--window-size-chars|--window-size-pixels|--check-config|-[ahoTvWwC])
+    --app-id|--toplevel-tag|--help|--override|--pty|--title|--version|--window-size-chars|--window-size-pixels|--check-config|-[ahoTvWwC])
         # Don't autocomplete for these flags
         : ;;
     *)

completions/bash/footclient

@@ -6,6 +6,7 @@ _footclient()
     local cur prev flags word commands match previous_words i offset
     flags=(
         "--app-id"
+        "--toplevel-tag"
         "--fullscreen"
         "--help"
         "--hold"
@@ -35,7 +36,7 @@ _footclient()
     for word in "${previous_words[@]}" ; do
         match=$(printf "$commands" | grep -Fx "$word" 2>/dev/null)
         if [[ ! -z "$match" ]] ; then
-            if [[ ${COMP_WORDS[i-1]} =~ ^(--app-id|--log-level|--server-socket|--term|--title|--window-size-pixels|--window-size-chars|--working-directory)$ ]] ; then
+            if [[ ${COMP_WORDS[i-1]} =~ ^(--app-id|--toplevel-tag|--log-level|--server-socket|--term|--title|--window-size-pixels|--window-size-chars|--working-directory)$ ]] ; then
                 (( i++ ))
                 continue
             fi
@@ -67,7 +68,7 @@ _footclient()
         COMPREPLY=( $(compgen -W "none error warning info" -- ${cur}) ) ;;
     --log-colorize|-l)
         COMPREPLY=( $(compgen -W "never always auto" -- ${cur}) ) ;;
-    --app-id|--help|--override|--title|--version|--window-size-chars|--window-size-pixels|-[ahoTvWw])
+    --app-id|--toplevel-tag|--help|--override|--title|--version|--window-size-chars|--window-size-pixels|-[ahoTvWw])
         # Don't autocomplete for these flags
         : ;;
     *)

completions/fish/foot.fish

@@ -6,6 +6,7 @@ complete -c foot -x -s f -l font               -a "(fc-list : family | sed 's/,/
 complete -c foot -x -s t -l term               -a '(find /usr/share/terminfo -type f -printf "%f\n")' -d "value to set the environment variable TERM to (foot)"
 complete -c foot -x -s T -l title                                                                     -d "initial window title"
 complete -c foot -x -s a -l app-id                                                                    -d "value to set the app-id property on the Wayland window to (foot)"
+complete -c foot -x      -l toplevel-tag                                                              -d "value to set the toplevel-tag property on the Wayland window to"
 complete -c foot    -s m -l maximized                                                                 -d "start in maximized mode"
 complete -c foot    -s F -l fullscreen                                                                -d "start in fullscreen mode"
 complete -c foot    -s L -l login-shell                                                               -d "start shell as a login shell"

completions/fish/footclient.fish

@@ -2,6 +2,7 @@ complete -c footclient -x                            -a "(__fish_complete_subcom
 complete -c footclient -x -s t -l term               -a '(find /usr/share/terminfo -type f -printf "%f\n")' -d "value to set the environment variable TERM to (foot)"
 complete -c footclient -x -s T -l title                                                                     -d "initial window title"
 complete -c footclient -x -s a -l app-id                                                                    -d "value to set the app-id property on the Wayland window to (foot)"
+complete -c footclient -x      -l toplevel-tag                                                              -d "value to set the toplevel-tag property on the Wayland window to"
 complete -c footclient    -s m -l maximized                                                                 -d "start in maximized mode"
 complete -c footclient    -s F -l fullscreen                                                                -d "start in fullscreen mode"
 complete -c footclient    -s L -l login-shell                                                               -d "start shell as a login shell"

completions/zsh/_foot

@@ -9,6 +9,7 @@ _arguments \
     '(-t --term)'{-t,--term}'[value to set the environment variable TERM to (foot)]:term:->terms' \
     '(-T --title)'{-T,--title}'[initial window title]:()' \
     '(-a --app-id)'{-a,--app-id}'[value to set the app-id property on the Wayland window to (foot)]:()' \
+    '--toplevel-tag=[value to set the toplevel-tag property on the Wayland window to]:()' \
     '(-m --maximized)'{-m,--maximized}'[start in maximized mode]' \
     '(-F --fullscreen)'{-F,--fullscreen}'[start in fullscreen mode]' \
     '(-L --login-shell)'{-L,--login-shell}'[start shell as a login shell]' \

completions/zsh/_footclient

@@ -5,6 +5,7 @@ _arguments \
     '(-t --term)'{-t,--term}'[value to set the environment variable TERM to (foot)]:term:->terms' \
     '(-T --title)'{-T,--title}'[initial window title]:()' \
     '(-a --app-id)'{-a,--app-id}'[value to set the app-id property on the Wayland window to (foot)]:()' \
+    '--toplevel-tag=[value to set the toplevel-tag property on the Wayland window to]:()' \
     '(-m --maximized)'{-m,--maximized}'[start in maximized mode]' \
     '(-F --fullscreen)'{-F,--fullscreen}'[start in fullscreen mode]' \
     '(-L --login-shell)'{-L,--login-shell}'[start shell as a login shell]' \

config.c

@@ -923,6 +923,9 @@ parse_section_main(struct context *ctx)
     else if (streq(key, "app-id"))
         return value_to_str(ctx, &conf->app_id);
 
+    else if (streq(key, "toplevel-tag"))
+        return value_to_str(ctx, &conf->toplevel_tag);
+
     else if (streq(key, "initial-window-size-pixels")) {
         if (!value_to_dimensions(ctx, &conf->size.width, &conf->size.height))
             return false;
@@ -3371,6 +3374,7 @@ config_load(struct config *conf, const char *conf_path,
         .shell = get_shell(),
         .title = xstrdup("foot"),
         .app_id = (as_server ? xstrdup("footclient") : xstrdup("foot")),
+        .toplevel_tag = xstrdup(""),
         .word_delimiters = xc32dup(U",│`|:\"'()[]{}<>"),
         .size = {
             .type = CONF_SIZE_PX,
@@ -3823,6 +3827,7 @@ config_clone(const struct config *old)
     conf->shell = xstrdup(old->shell);
     conf->title = xstrdup(old->title);
     conf->app_id = xstrdup(old->app_id);
+    conf->toplevel_tag = xstrdup(old->toplevel_tag);
     conf->word_delimiters = xc32dup(old->word_delimiters);
     conf->scrollback.indicator.text = xc32dup(old->scrollback.indicator.text);
     conf->server_socket_path = xstrdup(old->server_socket_path);
@@ -3922,6 +3927,7 @@ config_free(struct config *conf)
     free(conf->shell);
     free(conf->title);
     free(conf->app_id);
+    free(conf->toplevel_tag);
     free(conf->word_delimiters);
     spawn_template_free(&conf->bell.command);
     free(conf->scrollback.indicator.text);

config.h

@@ -219,6 +219,7 @@ struct config {
     char *shell;
     char *title;
     char *app_id;
+    char *toplevel_tag;
     char32_t *word_delimiters;
     bool login_shell;
     bool locked_title;

doc/foot.1.scd

@@ -67,6 +67,11 @@ the foot command line
 	Value to set the *app-id* property on the Wayland window
 	to. Default: _foot_ (normal mode), or _footclient_ (server mode).
 
+*toplevel-tag*=_TAG_
+	Value to set the *toplevel-tag* property on the Wayland window
+	to. The compositor can use this value for session management,
+	window rules etc. Default: _not set_
+
 *-m*,*--maximized*
 	Start in maximized mode. If both *--maximized* and *--fullscreen*
 	are specified, the _last_ one takes precedence.

doc/foot.ini.5.scd

@@ -429,6 +429,11 @@ empty string to be set, but it must be quoted: *KEY=""*)
 	apply window management rules. Default: _foot_ (normal mode), or
 	_footclient_ (server mode).
 
+*toplevel-tag*
+	Value to set the *toplevel-tag* property on the Wayland window
+	to. The compositor can use this value for session management,
+	window rules etc. Default: _not set_
+
 *bold-text-in-bright*
 	Semi-boolean. When enabled, bold text is rendered in a brighter
 	color (in addition to using a bold font). The color is brightened

doc/footclient.1.scd

@@ -33,6 +33,11 @@ terminal has terminated.
 	Value to set the *app-id* property on the Wayland window
 	to. Default: _foot_ (normal mode), or _footclient_ (server mode).
 
+*toplevel-tag*=_TAG_
+	Value to set the *toplevel-tag* property on the Wayland window
+	to. The compositor can use this value for session management,
+	window rules etc. Default: _not set_
+
 *-w*,*--window-size-pixels*=_WIDTHxHEIGHT_
 	Set initial window width and height, in pixels. Default: _700x500_.
 

foot-features.c

@@ -22,6 +22,12 @@ const char version_and_features[] =
     " -graphemes"
 #endif
 
+#if defined(HAVE_XDG_TOPLEVEL_TAG)
+    " +toplevel-tag"
+#else
+    " -toplevel-tag"
+#endif
+
 #if !defined(NDEBUG)
     " +assertions"
 #else

main.c

@@ -84,6 +84,7 @@ print_usage(const char *prog_name)
         "  -t,--term=TERM                           value to set the environment variable TERM to (" FOOT_DEFAULT_TERM ")\n"
         "  -T,--title=TITLE                         initial window title (foot)\n"
         "  -a,--app-id=ID                           window application ID (foot)\n"
+        "     --toplevel-tag=TAG                    set a custom toplevel tag\n"
         "  -m,--maximized                           start in maximized mode\n"
         "  -F,--fullscreen                          start in fullscreen mode\n"
         "  -L,--login-shell                         start shell as a login shell\n"
@@ -185,6 +186,7 @@ sanitize_signals(void)
 
 enum {
     PTY_OPTION = CHAR_MAX + 1,
+    TOPLEVEL_TAG_OPTION = CHAR_MAX + 2,
 };
 
 int
@@ -214,6 +216,7 @@ main(int argc, char *const *argv)
         {"term",                   required_argument, NULL, 't'},
         {"title",                  required_argument, NULL, 'T'},
         {"app-id",                 required_argument, NULL, 'a'},
+        {"toplevel-tag",           required_argument, NULL, TOPLEVEL_TAG_OPTION},
         {"login-shell",            no_argument,       NULL, 'L'},
         {"working-directory",      required_argument, NULL, 'D'},
         {"font",                   required_argument, NULL, 'f'},
@@ -285,6 +288,10 @@ main(int argc, char *const *argv)
             tll_push_back(overrides, xstrjoin("app-id=", optarg));
             break;
 
+        case TOPLEVEL_TAG_OPTION:
+            tll_push_back(overrides, xstrjoin("toplevel-tag=", optarg));
+            break;
+
         case 'D': {
             struct stat st;
             if (stat(optarg, &st) < 0 || !(st.st_mode & S_IFDIR)) {

meson.build

@@ -182,7 +182,12 @@ wl_proto_xml = [
   wayland_protocols_datadir / 'staging/xdg-toplevel-icon/xdg-toplevel-icon-v1.xml',
   wayland_protocols_datadir / 'staging/xdg-system-bell/xdg-system-bell-v1.xml',
   wayland_protocols_datadir / 'staging/color-management/color-management-v1.xml',
-  ]
+]
+
+if (wayland_protocols.version().version_compare('>=1.43'))
+  wl_proto_xml += [wayland_protocols_datadir / 'staging/xdg-toplevel-tag/xdg-toplevel-tag-v1.xml']
+  add_project_arguments('-DHAVE_XDG_TOPLEVEL_TAG=1', language: 'c')
+endif
 
 foreach prot : wl_proto_xml
   wl_proto_headers += custom_target(

tests/test-config.c

@@ -482,6 +482,7 @@ test_section_main(void)
     test_string(&ctx, &parse_section_main, "shell", &conf.shell);
     test_string(&ctx, &parse_section_main, "term", &conf.term);
     test_string(&ctx, &parse_section_main, "app-id", &conf.app_id);
+    test_string(&ctx, &parse_section_main, "toplevel-tag", &conf.toplevel_tag);
     test_string(&ctx, &parse_section_main, "utmp-helper", &conf.utmp_helper_path);
 
     test_c32string(&ctx, &parse_section_main, "word-delimiters", &conf.word_delimiters);

wayland.c

@@ -1548,6 +1548,17 @@ handle_global(void *data, struct wl_registry *registry,
             wayl->color_management.manager, &color_manager_listener, wayl);
     }
 
+#if defined(HAVE_XDG_TOPLEVEL_TAG)
+    else if (streq(interface, xdg_toplevel_tag_manager_v1_interface.name)) {
+        const uint32_t required = 1;
+        if (!verify_iface_version(interface, version, required))
+            return;
+
+        wayl->toplevel_tag_manager = wl_registry_bind(
+            wayl->registry, name, &xdg_toplevel_tag_manager_v1_interface, required);
+    }
+#endif
+
 #if defined(FOOT_IME_ENABLED) && FOOT_IME_ENABLED
     else if (streq(interface, zwp_text_input_manager_v3_interface.name)) {
         const uint32_t required = 1;
@@ -1791,7 +1802,7 @@ wayl_init(struct fdm *fdm, struct key_binding_manager *key_binding_manager,
     }
 
     if (wayl->toplevel_icon_manager == NULL) {
-        LOG_WARN("compositor does not implement the XDG toplevel icon protocol");
+        LOG_WARN("compositor does not implement the xdg-toplevel-icon protocol");
     }
 
 #if defined(FOOT_IME_ENABLED) && FOOT_IME_ENABLED
@@ -1870,6 +1881,11 @@ wayl_destroy(struct wayland *wayl)
         zwp_text_input_manager_v3_destroy(wayl->text_input_manager);
 #endif
 
+#if defined(HAVE_XDG_TOPLEVEL_TAG)
+    if (wayl->toplevel_tag_manager != NULL)
+        xdg_toplevel_tag_manager_v1_destroy(wayl->toplevel_tag_manager);
+#endif
+
     if (wayl->color_management.img_description != NULL)
         wp_image_description_v1_destroy(wayl->color_management.img_description);
     if (wayl->color_management.manager != NULL)
@@ -1995,6 +2011,21 @@ wayl_win_init(struct terminal *term, const char *token)
 
     xdg_toplevel_set_app_id(win->xdg_toplevel, conf->app_id);
 
+#if defined(HAVE_XDG_TOPLEVEL_TAG)
+    if (conf->toplevel_tag != NULL && conf->toplevel_tag[0] != '\0') {
+        if (wayl->toplevel_tag_manager != NULL) {
+            xdg_toplevel_tag_manager_v1_set_toplevel_tag(
+                wayl->toplevel_tag_manager, win->xdg_toplevel, conf->toplevel_tag);
+
+            /* TODO: the description is recommended to be the tag, but translated */
+            xdg_toplevel_tag_manager_v1_set_toplevel_description(
+                wayl->toplevel_tag_manager, win->xdg_toplevel, conf->toplevel_tag);
+        } else {
+            LOG_WARN("compositor does not implement the xdg-toplevel-tag protocol");
+        }
+    }
+#endif
+
     if (wayl->toplevel_icon_manager != NULL) {
         const char *app_id =
             term->app_id != NULL ? term->app_id : term->conf->app_id;

wayland.h

@@ -23,6 +23,10 @@
 #include <xdg-system-bell-v1.h>
 #include <xdg-toplevel-icon-v1.h>
 
+#if defined(HAVE_XDG_TOPLEVEL_TAG)
+ #include <xdg-toplevel-tag-v1.h>
+#endif
+
 #include <fcft/fcft.h>
 #include <tllist.h>
 
@@ -481,6 +485,10 @@ struct wayland {
     struct wp_presentation *presentation;
     uint32_t presentation_clock_id;
 
+#if defined(HAVE_XDG_TOPLEVEL_TAG)
+    struct xdg_toplevel_tag_manager_v1 *toplevel_tag_manager;
+#endif
+
 #if defined(FOOT_IME_ENABLED) && FOOT_IME_ENABLED
     struct zwp_text_input_manager_v3 *text_input_manager;
 #endif