From bc61a2cc74f65ab5bba51ba65edc1efd1269d510 Mon Sep 17 00:00:00 2001
From: Dmitry Zakharchenko <dmitz@disroot.org>
Date: Thu, 5 Jan 2023 14:57:48 +0200
Subject: [PATCH] swallow: sync with 0.4

---
 config.def.h |   6 ++--
 dwl.c        | 100 +++++++++++++++++++++++++++++++++++++++++++++++++--
 2 files changed, 100 insertions(+), 6 deletions(-)

diff --git a/config.def.h b/config.def.h
index a4f7c13d0..9dcedacd4 100644
--- a/config.def.h
+++ b/config.def.h
@@ -12,11 +12,11 @@ static const float fullscreen_bg[]         = {0.1, 0.1, 0.1, 1.0};
 static const char *tags[] = { "1", "2", "3", "4", "5", "6", "7", "8", "9" };
 
 static const Rule rules[] = {
-	/* app_id     title       tags mask     isfloating   monitor */
+	/* app_id     title       tags mask     isfloating  isterm  noswallow  monitor */
 	/* examples:
-	{ "Gimp",     NULL,       0,            1,           -1 },
+	{ "Gimp",     NULL,       0,            1,          0,      1,         -1 },
 	*/
-	{ "firefox",  NULL,       1 << 8,       0,           -1 },
+	{ "firefox",  NULL,       1 << 8,       0,          0,      1,         -1 },
 };
 
 /* layout(s) */
diff --git a/dwl.c b/dwl.c
index 19bb6ce34..262fa62c7 100644
--- a/dwl.c
+++ b/dwl.c
@@ -95,7 +95,8 @@ typedef struct {
 } Button;
 
 typedef struct Monitor Monitor;
-typedef struct {
+typedef struct Client Client;
+struct Client {
 	/* Must keep these three elements in this order */
 	unsigned int type; /* XDGShell or X11* */
 	struct wlr_box geom;  /* layout-relative, includes border */
@@ -124,9 +125,11 @@ typedef struct {
 #endif
 	unsigned int bw;
 	unsigned int tags;
-	int isfloating, isurgent, isfullscreen;
+	int isfloating, isurgent, isfullscreen, isterm, noswallow;
 	uint32_t resize; /* configure serial of a pending resize */
-} Client;
+	pid_t pid;
+	Client *swallowing, *swallowedby;
+};
 
 typedef struct {
 	uint32_t mod;
@@ -201,6 +204,8 @@ typedef struct {
 	const char *title;
 	unsigned int tags;
 	int isfloating;
+	int isterm;
+	int noswallow;
 	int monitor;
 } Rule;
 
@@ -310,6 +315,10 @@ static Monitor *xytomon(double x, double y);
 static struct wlr_scene_node *xytonode(double x, double y, struct wlr_surface **psurface,
 		Client **pc, LayerSurface **pl, double *nx, double *ny);
 static void zoom(const Arg *arg);
+static pid_t getparentprocess(pid_t p);
+static int isdescprocess(pid_t p, pid_t c);
+static Client *termforwin(Client *w);
+static void swallow(Client *c, Client *w);
 
 /* variables */
 static const char broken[] = "broken";
@@ -453,6 +462,8 @@ applyrules(Client *c)
 		if ((!r->title || strstr(title, r->title))
 				&& (!r->id || strstr(appid, r->id))) {
 			c->isfloating = r->isfloating;
+			c->isterm     = r->isterm;
+			c->noswallow  = r->noswallow;
 			newtags |= r->tags;
 			i = 0;
 			wl_list_for_each(m, &mons, link)
@@ -990,6 +1001,8 @@ createnotify(struct wl_listener *listener, void *data)
 	c->surface.xdg = xdg_surface;
 	c->bw = borderpx;
 
+	wl_client_get_credentials(c->surface.xdg->client->client, &c->pid, NULL, NULL);
+
 	LISTEN(&xdg_surface->events.map, &c->map, mapnotify);
 	LISTEN(&xdg_surface->events.unmap, &c->unmap, unmapnotify);
 	LISTEN(&xdg_surface->events.destroy, &c->destroy, destroynotify);
@@ -1308,6 +1321,61 @@ fullscreennotify(struct wl_listener *listener, void *data)
 	setfullscreen(c, client_wants_fullscreen(c));
 }
 
+pid_t
+getparentprocess(pid_t p)
+{
+	unsigned int v = 0;
+
+	FILE *f;
+	char buf[256];
+	snprintf(buf, sizeof(buf) - 1, "/proc/%u/stat", (unsigned)p);
+
+	if (!(f = fopen(buf, "r")))
+		return 0;
+
+	fscanf(f, "%*u %*s %*c %u", &v);
+	fclose(f);
+
+	return (pid_t)v;
+}
+
+int
+isdescprocess(pid_t p, pid_t c)
+{
+	while (p != c && c != 0)
+		c = getparentprocess(c);
+
+	return (int)c;
+}
+
+Client *
+termforwin(Client *w)
+{
+	Client *c;
+
+	if (!w->pid || w->isterm || w->noswallow)
+		return NULL;
+
+	wl_list_for_each(c, &clients, link)
+		if (c->isterm && !c->swallowing && c->pid && isdescprocess(c->pid, w->pid))
+			return c;
+
+	return NULL;
+}
+
+void
+swallow(Client *c, Client *w) {
+	c->bw = w->bw;
+	c->isfloating = w->isfloating;
+	c->isurgent = w->isurgent;
+	c->isfullscreen = w->isfullscreen;
+	resize(c, w->geom, 0);
+	wl_list_insert(&w->link, &c->link);
+	wl_list_insert(&w->flink, &c->flink);
+	wlr_scene_node_set_enabled(&w->scene->node, 0);
+	wlr_scene_node_set_enabled(&c->scene->node, 1);
+}
+
 void
 incnmaster(const Arg *arg)
 {
@@ -1528,6 +1596,20 @@ mapnotify(struct wl_listener *listener, void *data)
 	}
 	printstatus();
 
+	if (!c->noswallow) {
+		Client *p = termforwin(c);
+		if (p) {
+			c->swallowedby = p;
+			p->swallowing  = c;
+			wl_list_remove(&c->link);
+			wl_list_remove(&c->flink);
+			swallow(c,p);
+			wl_list_remove(&p->link);
+			wl_list_remove(&p->flink);
+			arrange(c->mon);
+		}
+	}
+
 unset_fullscreen:
 	m = c->mon ? c->mon : xytomon(c->geom.x, c->geom.y);
 	wl_list_for_each(w, &clients, link)
@@ -2409,6 +2491,18 @@ unmapnotify(struct wl_listener *listener, void *data)
 		grabc = NULL;
 	}
 
+	if (c->swallowing) {
+		c->swallowing->swallowedby = NULL;
+		c->swallowing = NULL;
+	}
+
+	if (c->swallowedby) {
+		setfullscreen(c->swallowedby, 0);
+		swallow(c->swallowedby, c);
+		c->swallowedby->swallowing = NULL;
+		c->swallowedby = NULL;
+	}
+
 	if (client_is_unmanaged(c)) {
 		if (c == exclusive_focus)
 			exclusive_focus = NULL;