implement window resizing (again)

4 files changed, 65 insertions, 9 deletions

diff --git a/src/display.c b/src/display.c
index ad4253d..a8c24bf 100644
--- a/src/display.c
+++ b/src/display.c
@@ -32,12 +32,6 @@ void runes_display_set_window_size(RunesTerm *t)
     t->xpixel = width;
     t->ypixel = height;
 
-    t->scr.max.row = t->ypixel / t->fonty;
-    t->scr.max.col = t->xpixel / t->fontx;
-
-    t->scr.scroll_top    = 0;
-    t->scr.scroll_bottom = t->scr.max.row - 1;
-
     old_cr = t->cr;
 
     /* XXX this should really use cairo_surface_create_similar_image, but when
@@ -84,6 +78,7 @@ void runes_display_set_window_size(RunesTerm *t)
         cairo_destroy(old_cr);
     }
 
+    runes_screen_set_window_size(t);
     runes_pty_backend_set_window_size(t);
 }
 
diff --git a/src/screen.c b/src/screen.c
index fa7182b..6fb4c4f 100644
--- a/src/screen.c
+++ b/src/screen.c
@@ -6,14 +6,64 @@
 
 void runes_screen_init(RunesTerm *t)
 {
+    UNUSED(t);
+    /* nothing (for now?) */
+}
+
+void runes_screen_set_window_size(RunesTerm *t)
+{
     RunesScreen *scr = &t->scr;
+    struct runes_row *old_rows = scr->rows;
+    struct runes_loc old_size;
     int i;
 
+    old_size.row = scr->max.row;
+    old_size.col = scr->max.col;
+
+    scr->max.row = t->ypixel / t->fonty;
+    scr->max.col = t->xpixel / t->fontx;
+
+    if (scr->max.row == 0) {
+        scr->max.row = 1;
+    }
+    if (scr->max.col == 0) {
+        scr->max.col = 1;
+    }
+
+    if (scr->max.row == old_size.row && scr->max.col == old_size.col) {
+        return;
+    }
+
+    if (scr->cur.row >= scr->max.row) {
+        scr->cur.row = scr->max.row - 1;
+    }
+    if (scr->cur.col > scr->max.col) {
+        scr->cur.col = scr->max.col;
+    }
+
+    scr->scroll_top    = 0;
+    scr->scroll_bottom = scr->max.row - 1;
+
     scr->rows = calloc(scr->max.row, sizeof(struct runes_row));
     for (i = 0; i < scr->max.row; ++i) {
         scr->rows[i].cells = calloc(
             scr->max.col, sizeof(struct runes_cell));
     }
+
+    if (old_rows) {
+        struct runes_loc overlap = {
+            scr->max.row < old_size.row ? scr->max.row : old_size.row,
+            scr->max.col < old_size.col ? scr->max.col : old_size.col
+        };
+
+        for (i = 0; i < overlap.row; ++i) {
+            memcpy(
+                scr->rows[i].cells, old_rows[i].cells,
+                overlap.col * sizeof(struct runes_cell));
+            free(old_rows[i].cells);
+        }
+        free(old_rows);
+    }
 }
 
 void runes_screen_process_string(RunesTerm *t, char *buf, size_t len)
@@ -496,6 +546,7 @@ void runes_screen_use_alternate_buffer(RunesTerm *t)
     runes_screen_save_cursor(t);
 
     scr->alternate = scr->rows;
+    scr->alternate_max = scr->max;
 
     scr->rows = calloc(scr->max.row, sizeof(struct runes_row));
     for (i = 0; i < scr->max.row; ++i) {
@@ -519,9 +570,11 @@ void runes_screen_use_normal_buffer(RunesTerm *t)
     free(scr->rows);
 
     scr->rows = scr->alternate;
+    scr->max = scr->alternate_max;
     scr->alternate = NULL;
 
     runes_screen_restore_cursor(t);
+    runes_screen_set_window_size(t);
 }
 
 void runes_screen_save_cursor(RunesTerm *t)
diff --git a/src/screen.h b/src/screen.h
index 38368a3..3296764 100644
--- a/src/screen.h
+++ b/src/screen.h
@@ -60,6 +60,7 @@ struct runes_row {
 struct runes_screen {
     struct runes_loc cur;
     struct runes_loc max;
+    struct runes_loc alternate_max;
     struct runes_loc saved;
 
     int scroll_top;
@@ -88,6 +89,7 @@ struct runes_screen {
 };
 
 void runes_screen_init(RunesTerm *t);
+void runes_screen_set_window_size(RunesTerm *t);
 void runes_screen_process_string(RunesTerm *t, char *buf, size_t len);
 void runes_screen_audible_bell(RunesTerm *t);
 void runes_screen_visual_bell(RunesTerm *t);
diff --git a/src/window-xlib.c b/src/window-xlib.c
index fc6f0f0..7325595 100644
--- a/src/window-xlib.c
+++ b/src/window-xlib.c
@@ -215,7 +215,7 @@ void runes_window_backend_start_loop(RunesTerm *t)
     void *data;
 
     XGetICValues(w->ic, XNFilterEvents, &mask, NULL);
-    XSelectInput(w->dpy, w->border_w, mask|KeyPressMask);
+    XSelectInput(w->dpy, w->border_w, mask|KeyPressMask|StructureNotifyMask);
     XSelectInput(
         w->dpy, w->w,
         mask|KeyPressMask|ButtonPressMask|ButtonReleaseMask|ButtonMotionMask|PointerMotionHintMask|EnterWindowMask|LeaveWindowMask|StructureNotifyMask|ExposureMask|FocusChangeMask);
@@ -414,8 +414,9 @@ static void runes_window_backend_resize_window(
     }
 
     if (width != t->xpixel || height != t->ypixel) {
+        XResizeWindow(w->dpy, w->w, width - 4, height - 4);
         cairo_xlib_surface_set_size(
-            cairo_get_target(w->backend_cr), width, height);
+            cairo_get_target(w->backend_cr), width - 4, height - 4);
         runes_display_set_window_size(t);
     }
 }
@@ -738,7 +739,12 @@ static void runes_window_backend_handle_configure_event(
 {
     RunesWindowBackend *w = &t->w;
 
-    while (XCheckTypedWindowEvent(w->dpy, w->w, ConfigureNotify, (XEvent *)e));
+    if (e->window != w->border_w) {
+        return;
+    }
+
+    while (XCheckTypedWindowEvent(
+        w->dpy, w->border_w, ConfigureNotify, (XEvent *)e));
     runes_window_backend_resize_window(t, e->width, e->height);
 }