basic layout command

include/sway/container.h

@@ -164,4 +164,6 @@ swayc_t *swayc_at(swayc_t *parent, double lx, double ly,
 void container_for_each_bfs(swayc_t *con, void (*f)(swayc_t *con, void *data),
 		void *data);
 
+swayc_t *swayc_change_layout(swayc_t *container, enum swayc_layouts layout);
+
 #endif

sway/commands.c

@@ -136,6 +136,7 @@ static struct cmd_handler handlers[] = {
 	{ "include", cmd_include },
 	{ "input", cmd_input },
 	{ "kill", cmd_kill },
+	{ "layout", cmd_layout },
 	{ "output", cmd_output },
 	{ "reload", cmd_reload },
 	{ "seat", cmd_seat },

sway/commands/layout.c

@@ -0,0 +1,65 @@
+#include <string.h>
+#include <strings.h>
+#include "sway/commands.h"
+#include "sway/container.h"
+#include "sway/layout.h"
+#include "log.h"
+
+struct cmd_results *cmd_layout(int argc, char **argv) {
+	struct cmd_results *error = NULL;
+	if (config->reading) {
+		return cmd_results_new(CMD_FAILURE, "layout", "Can't be used in config file.");
+	}
+	if (!config->active) {
+		return cmd_results_new(CMD_FAILURE, "layout", "Can only be used when sway is running.");
+	}
+	if ((error = checkarg(argc, "layout", EXPECTED_MORE_THAN, 0))) {
+		return error;
+	}
+	swayc_t *parent = config->handler_context.current_container;
+	if (!sway_assert(parent != NULL, "command called without container context")) {
+		return NULL;
+	}
+
+	// TODO: floating
+	/*
+	if (parent->is_floating) {
+		return cmd_results_new(CMD_FAILURE, "layout", "Unable to change layout of floating windows");
+	}
+	*/
+
+	while (parent->type == C_VIEW) {
+		parent = parent->parent;
+	}
+
+	// TODO: stacks and tabs
+
+	if (strcasecmp(argv[0], "default") == 0) {
+		swayc_change_layout(parent, parent->prev_layout);
+		if (parent->layout == L_NONE) {
+			swayc_t *output = swayc_parent_by_type(parent, C_OUTPUT);
+			swayc_change_layout(parent, default_layout(output));
+		}
+	} else {
+		if (parent->layout != L_TABBED && parent->layout != L_STACKED) {
+			parent->prev_layout = parent->layout;
+		}
+
+		if (strcasecmp(argv[0], "splith") == 0) {
+			swayc_change_layout(parent, L_HORIZ);
+		} else if (strcasecmp(argv[0], "splitv") == 0) {
+			swayc_change_layout(parent, L_VERT);
+		} else if (strcasecmp(argv[0], "toggle") == 0 && argc == 2 && strcasecmp(argv[1], "split") == 0) {
+			if (parent->layout == L_HORIZ && (parent->workspace_layout == L_NONE
+					|| parent->workspace_layout == L_HORIZ)) {
+				swayc_change_layout(parent, L_VERT);
+			} else {
+				swayc_change_layout(parent, L_HORIZ);
+			}
+		}
+	}
+
+	arrange_windows(parent, parent->width, parent->height);
+
+	return cmd_results_new(CMD_SUCCESS, NULL, NULL);
+}

sway/meson.build

@@ -14,6 +14,7 @@ sway_sources = files(
 	'commands/kill.c',
 	'commands/include.c',
 	'commands/input.c',
+	'commands/layout.c',
 	'commands/seat.c',
 	'commands/seat/attach.c',
 	'commands/seat/fallback.c',

sway/tree/container.c

@@ -400,3 +400,15 @@ void container_for_each_bfs(swayc_t *con, void (*f)(swayc_t *con, void *data),
 
 	list_free(queue);
 }
+
+swayc_t *swayc_change_layout(swayc_t *container, enum swayc_layouts layout) {
+	if (container->type == C_WORKSPACE) {
+		container->workspace_layout = layout;
+		if (layout == L_HORIZ || layout == L_VERT) {
+			container->layout = layout;
+		}
+	} else {
+		container->layout = layout;
+	}
+	return container;
+}