commit 2ddbda6b86c0d3c915ddd3e4e220682cfedd923f
from: Omar Polo <op@omarpolo.com>
date: Sat Jul 17 18:47:55 2021 UTC

lazy loading tabs on startup

don't load all the tabs when starting up, only the current one.  Defer
the loading of the others when switching to them.

commit - 9886bf9732750c285184211b957c1d0fffe21b4f
commit + 2ddbda6b86c0d3c915ddd3e4e220682cfedd923f
blob - ccfcc3cde3a0892912f5ffade64ebb70a6c3fd4c
blob + c056284f05d9f84a9ccb325ba4d6955bf8a7881e
--- ChangeLog
+++ ChangeLog
@@ -1,5 +1,7 @@
 2021-07-17  Omar Polo  <op@omarpolo.com>
 
+	* telescope.c (load_url): lazy loading for telescope: don't load all the tabs when starting up, only the current one.  Defer the loading of the others when switching to them.
+
 	* defaults.c (line_faces): don't underline links by default
 	add set-title option
 
blob - 1948ec501f1f9a143e3e54f00afa4d47b7c4f2fd
blob + 753f150d7d9f52feac477a5a20f94d92099386aa
--- cmd.c
+++ cmd.c
@@ -444,8 +444,7 @@ cmd_tab_next(struct buffer *buffer)
 
 	if ((t = TAILQ_NEXT(current_tab, tabs)) == NULL)
 		t = TAILQ_FIRST(&tabshead);
-	t->flags &= ~TAB_URGENT;
-	current_tab = t;
+	switch_to_tab(t);
 }
 
 void
@@ -455,8 +454,7 @@ cmd_tab_previous(struct buffer *buffer)
 
 	if ((t = TAILQ_PREV(current_tab, tabshead, tabs)) == NULL)
 		t = TAILQ_LAST(&tabshead, tabshead);
-	t->flags &= ~TAB_URGENT;
-	current_tab = t;
+	switch_to_tab(t);
 }
 
 void
blob - 45b3de8e43439b48ab6e38c7d4ae2962a91fdfce
blob + bb431883fc8665862e2ce9396f98d4ec3c9d57e6
--- telescope.c
+++ telescope.c
@@ -612,19 +612,43 @@ do_load_url(struct tab *tab, const char *url)
 	return 0;
 }
 
+/*
+ * Load url in tab.  If tab is marked as lazy, only prepare the url
+ * but don't load it.  If tab is lazy and a url was already prepared,
+ * do load it!
+ */
 void
 load_url(struct tab *tab, const char *url)
 {
-	if (tab->hist_cur != NULL)
-		hist_clear_forward(&tab->hist, TAILQ_NEXT(tab->hist_cur, entries));
+	int lazy;
 
-	if ((tab->hist_cur = calloc(1, sizeof(*tab->hist_cur))) == NULL) {
-		event_loopbreak();
-		return;
+	lazy = tab->flags & TAB_LAZY;
+
+	if (lazy && tab->hist_cur != NULL) {
+		lazy = 0;
+		tab->flags &= ~TAB_LAZY;
 	}
 
-	hist_push(&tab->hist, tab->hist_cur);
-	if (do_load_url(tab, url))
+	if (!lazy || tab->hist_cur == NULL) {
+		if (tab->hist_cur != NULL)
+			hist_clear_forward(&tab->hist,
+			    TAILQ_NEXT(tab->hist_cur, entries));
+
+		if ((tab->hist_cur = calloc(1, sizeof(*tab->hist_cur))) == NULL) {
+			event_loopbreak();
+			return;
+		}
+
+		strlcpy(tab->buffer.page.title, url,
+		    sizeof(tab->buffer.page.title));
+		hist_push(&tab->hist, tab->hist_cur);
+
+		if (lazy)
+			strlcpy(tab->hist_cur->h, url,
+			    sizeof(tab->hist_cur->h));
+	}
+
+	if (!lazy && do_load_url(tab, url))
 		erase_buffer(&tab->buffer);
 }
 
@@ -951,8 +975,7 @@ main(int argc, char * const *argv)
 			new_tab(url);
 
 		sandbox_ui_process();
-		ui_refresh();
-		event_dispatch();
+		ui_main_loop();
 		ui_end();
 	}
 
blob - db1e9f2418b4cad2132d76acede8ae8f7a818453
blob + 148469949ebb5531445895b7e55ea8c388e9a39f
--- telescope.h
+++ telescope.h
@@ -181,6 +181,7 @@ struct buffer {
 
 #define TAB_CURRENT	0x1	/* only for save_session */
 #define TAB_URGENT	0x2
+#define TAB_LAZY	0x4	/* to lazy load tabs */
 
 #define NEW_TAB_URL	"about:new"
 
@@ -315,7 +316,7 @@ void		 sandbox_fs_process(void);
 void		 load_about_url(struct tab*, const char*);
 void		 load_gemini_url(struct tab*, const char*);
 void		 load_via_proxy(struct tab *, const char *, struct proxy *);
-void		 load_url(struct tab*, const char*);
+void		 load_url(struct tab *, const char *);
 int		 load_previous_page(struct tab*);
 int		 load_next_page(struct tab*);
 void		 stop_tab(struct tab*);
blob - b8d6a18ad2d752e7578c0a29eacad9b7310ca443
blob + aad33da1c3ba106216a61b7bd158d76fe593263b
--- ui.c
+++ ui.c
@@ -76,6 +76,11 @@ static void		 rec_compute_help(struct kmap*, char*, si
 static void		 recompute_help(void);
 static void		 update_loading_anim(int, short, void*);
 static void		 stop_loading_anim(struct tab*);
+
+/*
+ * Used to know when we're finished loading.
+ */
+static int		 operating;
 
 static int		 should_rearrange_windows;
 static int		 too_small;
@@ -1103,12 +1108,15 @@ stop_loading_anim(struct tab *tab)
 void
 load_url_in_tab(struct tab *tab, const char *url)
 {
+	if (!operating) {
+		load_url(tab, url);
+		return;
+	}
+
 	message("Loading %s...", url);
 	start_loading_anim(tab);
 	load_url(tab, url);
 
-	tab->buffer.curs_x = 0;
-	tab->buffer.curs_y = 0;
 	redraw_tab(tab);
 }
 
@@ -1117,6 +1125,9 @@ switch_to_tab(struct tab *tab)
 {
 	current_tab = tab;
 	tab->flags &= ~TAB_URGENT;
+
+	if (operating && tab->flags & TAB_LAZY)
+		load_url_in_tab(tab, tab->hist_cur->h);
 }
 
 unsigned int
@@ -1141,6 +1152,8 @@ new_tab(const char *url)
 	TAILQ_INIT(&tab->buffer.head);
 
 	tab->id = tab_new_id();
+	if (!operating)
+		tab->flags |= TAB_LAZY;
 	switch_to_tab(tab);
 
 	if (TAILQ_EMPTY(&tabshead))
@@ -1278,9 +1291,13 @@ ui_init()
 }
 
 void
-ui_refresh(void)
+ui_main_loop(void)
 {
+	operating = 1;
+	switch_to_tab(current_tab);
 	redraw_tab(current_tab);
+
+	event_dispatch();
 }
 
 void
blob - 4842da52ee6c87e17611c8976f9de9f6ed722b6f
blob + bbfbc375cd03917338fadb34a1a8f18538daa70d
--- ui.h
+++ ui.h
@@ -113,7 +113,7 @@ struct tab	*new_tab(const char *);
 unsigned int	 tab_new_id(void);
 int		 ui_print_colors(void);
 int		 ui_init(void);
-void		 ui_refresh(void);
+void		 ui_main_loop(void);
 void		 ui_on_tab_loaded(struct tab *);
 void		 ui_on_tab_refresh(struct tab *);
 const char	*ui_keyname(int);