Implement bar gaps

Adds the bar subcommand `gaps <amount>|<horizontal> <vertical>|<top>
<right> <bottom> <left>` to set gaps for swaybar. Due to restrictions on
margins for a layer_surface, only the sides that are anchored to an edge
of the screen can have gaps. Since there is support for per-side outer
gaps for workspaces, those should be able to be used instead for the
last side.

2 files changed, 61 insertions, 0 deletions

diff --git a/sway/commands/bar.c b/sway/commands/bar.c
index f9ed530e..0cf94907 100644
--- a/sway/commands/bar.c
+++ b/sway/commands/bar.c
@@ -14,6 +14,7 @@ static struct cmd_handler bar_handlers[] = {
 	{ "colors", bar_cmd_colors },
 	{ "context_button", bar_cmd_context_button },
 	{ "font", bar_cmd_font },
+	{ "gaps", bar_cmd_gaps },
 	{ "height", bar_cmd_height },
 	{ "hidden_state", bar_cmd_hidden_state },
 	{ "icon_theme", bar_cmd_icon_theme },
diff --git a/sway/commands/bar/gaps.c b/sway/commands/bar/gaps.c
new file mode 100644
index 00000000..f78f3742
--- /dev/null
+++ b/sway/commands/bar/gaps.c
@@ -0,0 +1,60 @@
+#include <stdlib.h>
+#include <string.h>
+#include <strings.h>
+#include "sway/commands.h"
+#include "sway/ipc-server.h"
+#include "log.h"
+
+struct cmd_results *bar_cmd_gaps(int argc, char **argv) {
+	struct cmd_results *error = NULL;
+	if ((error = checkarg(argc, "gaps", EXPECTED_AT_LEAST, 1))) {
+		return error;
+	}
+	if ((error = checkarg(argc, "gaps", EXPECTED_AT_MOST, 4))) {
+		return error;
+	}
+	if (!config->current_bar) {
+		return cmd_results_new(CMD_FAILURE, "bar gaps", "No bar defined.");
+	}
+
+	int top = 0, right = 0, bottom = 0, left = 0;
+
+	for (int i = 0; i < argc; i++) {
+		char *end;
+		int amount = strtol(argv[i], &end, 10);
+		if (strlen(end) && strcasecmp(end, "px") != 0) {
+			return cmd_results_new(CMD_INVALID, "bar gaps",
+					"Expected 'bar [<bar-id>] gaps <all> | <horizonal> "
+					"<vertical> | <top> <right> <bottom> <left>'");
+		}
+
+		if (i == 0) {
+			top = amount;
+		}
+		if (i == 0 || i == 1) {
+			right = amount;
+		}
+		if (i == 0 || i == 2) {
+			bottom = amount;
+		}
+		if (i == 0 || i == 1 || i == 3) {
+			left = amount;
+		}
+	}
+
+	config->current_bar->gaps.top = top;
+	config->current_bar->gaps.right = right;
+	config->current_bar->gaps.bottom = bottom;
+	config->current_bar->gaps.left = left;
+
+	wlr_log(WLR_DEBUG, "Setting bar gaps to %d %d %d %d on bar: %s",
+			config->current_bar->gaps.top, config->current_bar->gaps.right,
+			config->current_bar->gaps.bottom, config->current_bar->gaps.left,
+			config->current_bar->id);
+
+	if (!config->reading) {
+		ipc_event_barconfig_update(config->current_bar);
+	}
+
+	return cmd_results_new(CMD_SUCCESS, NULL, NULL);
+}