commands: introduce non_desktop command for output

This command allows users to set a given output as non-desktop. The output is
offered to the drm-lease-manager interface if available, for clients to lease.

include/sway/commands.h

@@ -284,6 +284,7 @@ sway_cmd output_cmd_disable;
 sway_cmd output_cmd_dpms;
 sway_cmd output_cmd_enable;
 sway_cmd output_cmd_max_render_time;
+sway_cmd output_cmd_non_desktop;
 sway_cmd output_cmd_mode;
 sway_cmd output_cmd_modeline;
 sway_cmd output_cmd_position;

sway/commands/output.c

@@ -16,6 +16,7 @@ static const struct cmd_handler output_handlers[] = {
 	{ "max_render_time", output_cmd_max_render_time },
 	{ "mode", output_cmd_mode },
 	{ "modeline", output_cmd_modeline },
+	{ "non_desktop", output_cmd_non_desktop },
 	{ "pos", output_cmd_position },
 	{ "position", output_cmd_position },
 	{ "power", output_cmd_power },

sway/commands/output/non_desktop.c

@@ -0,0 +1,106 @@
+#include <strings.h>
+#include <wlr/types/wlr_output_damage.h>
+#include "sway/commands.h"
+#include "sway/config.h"
+#include "sway/output.h"
+#include "sway/server.h"
+#include "log.h"
+#include "util.h"
+
+static int find_non_desktop_output(const void *item, const void *data)
+{
+	const struct sway_output_non_desktop *output = item;
+	const char *name = data;
+	return strcmp(output->wlr_output->name, name);
+}
+
+static int find_output(const void *item, const void *data)
+{
+	const struct sway_output *output = item;
+	const char *name = data;
+	return strcmp(output->wlr_output->name, name);
+}
+
+struct cmd_results *output_cmd_non_desktop(int argc, char **argv) {
+	if (argc == 0) {
+		return cmd_results_new(CMD_INVALID, "Missing non_desktop argument");
+	}
+
+	struct output_config *oc = config->handler_context.output_config;
+
+	if (strcmp(oc->name, "*") == 0) {
+		return cmd_results_new(CMD_INVALID,
+			"Cannot apply non_desktop to all outputs");
+	}
+
+	if (parse_boolean(argv[0], true)) {
+		int index = list_seq_find(root->outputs, find_output, oc->name);
+		if (index == -1) {
+			return cmd_results_new(CMD_FAILURE, "unknown output %s ", oc->name);
+		}
+
+		struct sway_output *output = root->outputs->items[index];
+		struct wlr_output *wlr_output = output->wlr_output;
+		wlr_output->non_desktop = true;
+
+		sway_log(SWAY_DEBUG, "output %s (%p) non-desktop on", wlr_output->name,
+			wlr_output);
+
+		output_disable(output);
+		wlr_output_layout_remove(root->output_layout, wlr_output);
+
+		struct sway_output_non_desktop *non_desktop =
+			output_non_desktop_create(wlr_output);
+		list_add(root->non_desktop_outputs, non_desktop);
+		
+		if (server.drm_lease_manager) {
+			wlr_drm_lease_v1_manager_offer_output(server.drm_lease_manager,
+				wlr_output);
+		}
+
+	} else {
+		int index = list_seq_find(root->non_desktop_outputs,
+			find_non_desktop_output, oc->name);
+		if (index == -1) {
+			return cmd_results_new(CMD_FAILURE, "unknown non-desktop output %s",
+				oc->name);
+		}
+		struct sway_output_non_desktop *non_desktop =
+			root->non_desktop_outputs->items[index];
+		struct wlr_output *wlr_output = non_desktop->wlr_output;
+
+		wlr_output->non_desktop = false;
+
+		sway_log(SWAY_DEBUG, "output %s (%p) non-desktop off", wlr_output->name,
+			wlr_output);
+		
+		if (server.drm_lease_manager) {
+			wlr_drm_lease_v1_manager_withdraw_output(server.drm_lease_manager,
+				wlr_output);
+		}
+
+		struct sway_output *output = wlr_output->data;
+		if (output) {
+			output_enable(output);
+		} else {
+			struct sway_output *output = output_create(wlr_output);
+			if (!output) {
+				sway_log(SWAY_ERROR, "failed to allocate wlr_output");
+				wlr_output->non_desktop = true;
+				if (server.drm_lease_manager) {
+					wlr_drm_lease_v1_manager_withdraw_output(
+						server.drm_lease_manager, wlr_output);
+				}
+				return cmd_results_new(CMD_FAILURE, "failed to create output");;
+			}
+
+			output_init(output, &server);
+		}
+
+		list_del(root->non_desktop_outputs, index);
+		wl_list_remove(&non_desktop->destroy.link);
+		free(non_desktop);
+	}
+
+	return cmd_results_new(CMD_SUCCESS, NULL);
+}

sway/meson.build

@@ -189,6 +189,7 @@ sway_sources = files(
 	'commands/output/dpms.c',
 	'commands/output/enable.c',
 	'commands/output/max_render_time.c',
+	'commands/output/non_desktop.c',
 	'commands/output/mode.c',
 	'commands/output/position.c',
 	'commands/output/power.c',

sway/sway-output.5.scd

@@ -180,6 +180,11 @@ must be separated by one space. For example:
 	updated to work with different bit depths. This command is experimental,
 	and may be removed or changed in the future.
 
+*output* <name> non_desktop on|off
+	Enables or disables the non-desktop property of a given output. When
+	enabled, the output is disabled and offered to the drm-lease-manager
+	interface if it is available.
+
 # SEE ALSO
 
 *sway*(5) *sway-input*(5)