Apply OSC 8 hyperlinks patch

Ref tmux#911

Patch by Nicholas Marriott
tmux#911 (comment)
https://github.com/tmux/tmux/files/3851118/tmux-hyperlinks.diff.txt

grid.c

@@ -37,12 +37,12 @@
 
 /* Default grid cell data. */
 const struct grid_cell grid_default_cell = {
-	{ { ' ' }, 0, 1, 1 }, 0, 0, 8, 8, 0
+	{ { ' ' }, 0, 1, 1 }, 0, 0, 8, 8, 0, 0
 };
 
 /* Cleared grid cell data. */
 const struct grid_cell grid_cleared_cell = {
-	{ { ' ' }, 0, 1, 1 }, 0, GRID_FLAG_CLEARED, 8, 8, 0
+	{ { ' ' }, 0, 1, 1 }, 0, GRID_FLAG_CLEARED, 8, 8, 0, 0
 };
 static const struct grid_cell_entry grid_cleared_entry = {
 	GRID_FLAG_CLEARED, { .data = { 0, 8, 8, ' ' } }
@@ -84,6 +84,8 @@ grid_need_extended_cell(const struct grid_cell_entry *gce,
 		return (1);
 	if (gc->us != 0) /* only supports 256 or RGB */
 		return (1);
+	if (gc->link != 0)
+		return (1);
 	return (0);
 }
 
@@ -221,6 +223,8 @@ grid_cells_equal(const struct grid_cell *gca, const struct grid_cell *gcb)
 		return (0);
 	if (gca->attr != gcb->attr || gca->flags != gcb->flags)
 		return (0);
+	if (gca->link != gcb->link)
+		return (0);
 	if (gca->data.width != gcb->data.width)
 		return (0);
 	if (gca->data.size != gcb->data.size)
@@ -479,6 +483,7 @@ grid_get_cell1(struct grid_line *gl, u_int px, struct grid_cell *gc)
 		gc->bg |= COLOUR_FLAG_256;
 	gc->us = 0;
 	utf8_set(&gc->data, gce->data.data);
+	gc->link = 0;
 }
 
 /* Get cell for reading. */

input.c

@@ -133,6 +133,7 @@ static void	input_set_state(struct window_pane *,
 static void	input_reset_cell(struct input_ctx *);
 
 static void	input_osc_4(struct input_ctx *, const char *);
+static void	input_osc_8(struct input_ctx *, const char *);
 static void	input_osc_10(struct input_ctx *, const char *);
 static void	input_osc_11(struct input_ctx *, const char *);
 static void	input_osc_52(struct input_ctx *, const char *);
@@ -2225,6 +2226,9 @@ input_exit_osc(struct input_ctx *ictx)
 			server_status_window(ictx->wp->window);
 		}
 		break;
+	case 8:
+		input_osc_8(ictx, p);
+		break;
 	case 10:
 		input_osc_10(ictx, p);
 		break;
@@ -2433,6 +2437,38 @@ input_osc_4(struct input_ctx *ictx, const char *p)
 	free(copy);
 }
 
+/* Handle the OSC 8 sequence for writing hyperlinks. */
+static void
+input_osc_8(struct input_ctx *ictx, const char *p)
+{
+	struct grid_cell	*gc = &ictx->cell.cell;
+	char			*end;
+	struct hyperlink	*hl;
+
+	if ((end = strchr(p, ';')) == NULL)
+		goto bad;
+	end++;
+	if (*end == '\0') {
+		gc->link = 0;
+		return;
+	}
+
+	/* XXX parse ID and check pane tree, reuse entry if present */
+
+	hl = xcalloc(1, sizeof *hl);
+	hl->id = ++next_hyperlink;
+	hl->link = xstrdup(end);
+	RB_INSERT (hyperlinks, &hyperlinks, hl);
+
+	log_debug("hyperlink %u = %s", hl->id, hl->link);
+
+	gc->link = hl->id;
+	return;
+
+bad:
+	log_debug("bad OSC 8 %s", p);
+}
+
 /* Handle the OSC 10 sequence for setting foreground colour. */
 static void
 input_osc_10(struct input_ctx *ictx, const char *p)

screen-write.c

@@ -36,7 +36,7 @@ static const struct grid_cell *screen_write_combine(struct screen_write_ctx *,
 		    const struct utf8_data *, u_int *);
 
 static const struct grid_cell screen_write_pad_cell = {
-	{ { 0 }, 0, 0, 0 }, 0, GRID_FLAG_PADDING, 0, 8, 8
+	{ { 0 }, 0, 0, 0 }, 0, GRID_FLAG_PADDING, 0, 8, 8, 0
 };
 
 struct screen_write_collect_item {

server.c

@@ -42,6 +42,9 @@
 
 struct clients		 clients;
 
+struct hyperlinks	 hyperlinks = RB_INITIALIZER();
+u_int			 next_hyperlink;
+
 struct tmuxproc		*server_proc;
 static int		 server_fd = -1;
 static int		 server_exit;
@@ -57,6 +60,25 @@ static void	server_child_signal(void);
 static void	server_child_exited(pid_t, int);
 static void	server_child_stopped(pid_t, int);
 
+RB_GENERATE(hyperlinks, hyperlink, entry, server_cmp_hyperlink);
+
+/* Compare two hyperlinks. */
+int
+server_cmp_hyperlink(struct hyperlink *hl1, struct hyperlink *hl2)
+{
+	return (hl1->id - hl2->id);
+}
+
+/* Get hyperlink. */
+struct hyperlink *
+server_get_hyperlink(u_int id)
+{
+	struct hyperlink	hl;
+
+	hl.id = id;
+	return (RB_FIND(hyperlinks, &hyperlinks, &hl));
+}
+
 /* Set marked pane. */
 void
 server_set_marked(struct session *s, struct winlink *wl, struct window_pane *wp)

style.c

@@ -30,7 +30,7 @@
 
 /* Default style. */
 static struct style style_default = {
-	{ { { ' ' }, 0, 1, 1 }, 0, 0, 8, 8, 0  },
+	{ { { ' ' }, 0, 1, 1 }, 0, 0, 8, 8, 0, 0 },
 
 	8,
 	STYLE_ALIGN_DEFAULT,

tmux.h

@@ -276,6 +276,8 @@ enum tty_code_code {
 	TTYC_EL1,
 	TTYC_ENACS,
 	TTYC_FSL,
+	TTYC_HLS,
+	TTYC_HLR,
 	TTYC_HOME,
 	TTYC_HPA,
 	TTYC_ICH,
@@ -636,6 +638,7 @@ struct grid_cell {
 	int			fg;
 	int			bg;
 	int			us;
+	u_int			link;
 } __packed;
 struct grid_cell_entry {
 	u_char			flags;
@@ -677,6 +680,14 @@ struct grid {
 	struct grid_line	*linedata;
 };
 
+/* Hyperlink tree entry. */
+struct hyperlink {
+	u_int			 id;
+	const char		*link;
+	RB_ENTRY(hyperlink)	 entry;
+};
+RB_HEAD(hyperlinks, hyperlink);
+
 /* Style alignment. */
 enum style_align {
 	STYLE_ALIGN_DEFAULT,
@@ -2197,6 +2208,11 @@ void	 file_push(struct client_file *);
 extern struct tmuxproc *server_proc;
 extern struct clients clients;
 extern struct cmd_find_state marked_pane;
+extern struct hyperlinks hyperlinks;
+extern u_int next_hyperlink;
+int	 server_cmp_hyperlink(struct hyperlink *, struct hyperlink *);
+struct hyperlink *server_get_hyperlink(u_int);
+RB_PROTOTYPE(hyperlinks, hyperlink, entry, server_cmp_hyperlink);
 void	 server_set_marked(struct session *, struct winlink *,
 	     struct window_pane *);
 void	 server_clear_marked(void);

tty-term.c

@@ -92,6 +92,8 @@ static const struct tty_term_code_entry tty_term_codes[] = {
 	[TTYC_EL] = { TTYCODE_STRING, "el" },
 	[TTYC_ENACS] = { TTYCODE_STRING, "enacs" },
 	[TTYC_FSL] = { TTYCODE_STRING, "fsl" },
+	[TTYC_HLS] = { TTYCODE_STRING, "Hls" },
+	[TTYC_HLR] = { TTYCODE_STRING, "Hlr" },
 	[TTYC_HOME] = { TTYCODE_STRING, "home" },
 	[TTYC_HPA] = { TTYCODE_STRING, "hpa" },
 	[TTYC_ICH1] = { TTYCODE_STRING, "ich1" },

tty.c

@@ -1329,6 +1329,7 @@ tty_draw_line(struct tty *tty, struct window_pane *wp, struct screen *s,
 		    gcp->fg != last.fg ||
 		    gcp->bg != last.bg ||
 		    gcp->us != last.us ||
+		    gcp->link != last.link ||
 		    ux + width + gcp->data.width > nx ||
 		    (sizeof buf) - len < gcp->data.size)) {
 			tty_attributes(tty, &last, wp);
@@ -1927,6 +1928,8 @@ tty_reset(struct tty *tty)
 	struct grid_cell	*gc = &tty->cell;
 
 	if (!grid_cells_equal(gc, &grid_default_cell)) {
+		if (gc->link != 0)
+			tty_putcode(tty, TTYC_HLR);
 		if ((gc->attr & GRID_ATTR_CHARSET) && tty_acs_needed(tty))
 			tty_putcode(tty, TTYC_RMACS);
 		tty_putcode(tty, TTYC_SGR0);
@@ -2209,6 +2212,29 @@ tty_cursor(struct tty *tty, u_int cx, u_int cy)
 	tty->cy = cy;
 }
 
+static void
+tty_hyperlink(struct tty *tty, const struct grid_cell *gc)
+{
+	struct hyperlink	*hl;
+	char			 s[16];
+
+	if (gc->link == tty->cell.link)
+		return;
+	tty->cell.link = gc->link;
+
+	if (gc->link == 0)
+		tty_putcode(tty, TTYC_HLR);
+	else {
+		hl = server_get_hyperlink(gc->link);
+		if (hl == NULL)
+			tty_putcode(tty, TTYC_HLR);
+		else {
+			snprintf(s, sizeof s, "%u", hl->id);
+			tty_putcode_ptr2(tty, TTYC_HLS, s, hl->link);
+		}
+	}
+}
+
 void
 tty_attributes(struct tty *tty, const struct grid_cell *gc,
     struct window_pane *wp)
@@ -2223,7 +2249,8 @@ tty_attributes(struct tty *tty, const struct grid_cell *gc,
 	    gc->attr == tty->last_cell.attr &&
 	    gc->fg == tty->last_cell.fg &&
 	    gc->bg == tty->last_cell.bg &&
-	    gc->us == tty->last_cell.us)
+	    gc->us == tty->last_cell.us &&
+	    gc->link == tty->last_cell.link)
 		return;
 	tty->last_wp = (wp != NULL ? (int)wp->id : -1);
 	memcpy(&tty->last_cell, gc, sizeof tty->last_cell);
@@ -2306,6 +2333,9 @@ tty_attributes(struct tty *tty, const struct grid_cell *gc,
 		tty_putcode(tty, TTYC_SMOL);
 	if ((changed & GRID_ATTR_CHARSET) && tty_acs_needed(tty))
 		tty_putcode(tty, TTYC_SMACS);
+
+	/* Set hyperlink if any. */
+	tty_hyperlink(tty, gc);
 }
 
 static void