From a6a13311b4e63c735cac9d6ac9ecedad752d31d7 Mon Sep 17 00:00:00 2001
From: Simon Tatham <anakin@pobox.com>
Date: Wed, 24 Jul 2019 18:56:07 +0100
Subject: [PATCH] Revert "Bounds-check terminal selection when clearing
 scrollback."

This reverts commit 80f5a009f647aacd492c6e1e7a5f450156cabe13.

After a bit more thought, I've decided it's the wrong way to solve the
problem. We shouldn't really be _changing_ the current selection
bounds in response to an event that touches the range they cover. With
this fix in place, if you clear the scrollback while a selection
partly overlaps it, and then extend the modified selection, you'll get
a selection one of whose endpoints is something you never specified as
a selection endpoint at all, and possibly paste the wrong text.

A better fix is to do the same thing we do about any other event that
touches the range covered by the selection: get rid of the selection
completely. For ease of cherry-picking (in case anyone needs to apply
the good fix in some downstream branch, or whatever), I'll make that
change separately in the next commit.
---
 terminal.c | 23 -----------------------
 terminal.h |  5 -----
 2 files changed, 28 deletions(-)

diff --git a/terminal.c b/terminal.c
index a0596b8d..c1a12c04 100644
--- a/terminal.c
+++ b/terminal.c
@@ -1600,24 +1600,6 @@ void term_reconfig(Terminal *term, Conf *conf)
     term_copy_stuff_from_conf(term);
 }
 
-/*
- * Ensure the position variables describing the ends of the terminal
- * selection are in bounds with respect to the actual extent of the
- * screen and scrollback.
- */
-static void term_selection_bounds_check(Terminal *term)
-{
-    pos lo, hi;
-    lo.y = -count234(term->scrollback);
-    lo.x = 0;
-    hi.y = count234(term->screen);
-    hi.x = term->cols - 1;
-
-    term->selstart = bound_pos(term->selstart, lo, hi);
-    term->selend = bound_pos(term->selend, lo, hi);
-    term->selanchor = bound_pos(term->selanchor, lo, hi);
-}
-
 /*
  * Clear the scrollback.
  */
@@ -1639,11 +1621,6 @@ void term_clrsb(Terminal *term)
 	sfree(line);            /* this is compressed data, not a termline */
     }
 
-    /*
-     * Make sure we didn't invalidate selstart and selend in the process.
-     */
-    term_selection_bounds_check(term);
-
     /*
      * When clearing the scrollback, we also truncate any termlines on
      * the current screen which have remembered data from a previous
diff --git a/terminal.h b/terminal.h
index 8da3b9b4..1ed0b17d 100644
--- a/terminal.h
+++ b/terminal.h
@@ -475,9 +475,4 @@ static inline bool decpos_fn(pos *p, int cols)
 #define incpos(p) incpos_fn(&(p), GET_TERM_COLS)
 #define decpos(p) decpos_fn(&(p), GET_TERM_COLS)
 
-static inline pos bound_pos(pos p, pos lo, pos hi)
-{
-    return poslt(p, lo) ? lo : poslt(p, hi) ? p : hi;
-}
-
 #endif