From: Pip Cet <pipcet@gmail.com>
Date: Sun, 27 Sep 2020 15:40:07 +0000 (+0200)
Subject: Fix more single-byte accesses caused by bytepos/charpos confusion
X-Git-Tag: emacs-28.0.90~5848
X-Git-Url: http://git.eshelyaron.com/gitweb/?a=commitdiff_plain;h=a492013d07c59fab8eb9779924b384181e878a1a;p=emacs.git

Fix more single-byte accesses caused by bytepos/charpos confusion

* src/cmds.c (internal_self_insert): Use FETCH_BYTE, not
FETCH_CHAR, for a decremented byte position (bug#41520).

* src/xdisp.c (Fwindow_text_pixel_size, trailing_whitespace_p): Ditto.
---

diff --git a/src/cmds.c b/src/cmds.c
index 90526612b7a..c29cf00dad1 100644
--- a/src/cmds.c
+++ b/src/cmds.c
@@ -390,7 +390,7 @@ internal_self_insert (int c, EMACS_INT n)
 		     by spaces so that the remaining text won't move.  */
 		  ptrdiff_t actual = PT_BYTE;
 		  actual -= prev_char_len (actual);
-		  if (FETCH_CHAR (actual) == '\t')
+		  if (FETCH_BYTE (actual) == '\t')
 		    /* Rather than add spaces, let's just keep the tab. */
 		    chars_to_delete--;
 		  else
diff --git a/src/xdisp.c b/src/xdisp.c
index 3d40878be65..ecd23e0d0fc 100644
--- a/src/xdisp.c
+++ b/src/xdisp.c
@@ -10619,7 +10619,7 @@ include the height of both, if present, in the return value.  */)
       while (bpos > BEGV_BYTE)
 	{
 	  dec_both (&start, &bpos);
-	  c = FETCH_CHAR (bpos);
+	  c = FETCH_BYTE (bpos);
 	  if (!(c == ' ' || c == '\t'))
 	    break;
 	}
@@ -10641,7 +10641,7 @@ include the height of both, if present, in the return value.  */)
       while (bpos > BEGV_BYTE)
 	{
 	  dec_both (&end, &bpos);
-	  c = FETCH_CHAR (bpos);
+	  c = FETCH_BYTE (bpos);
 	  if (!(c == ' ' || c == '\t' || c == '\n' || c == '\r'))
 	    break;
 	}
@@ -22277,7 +22277,7 @@ trailing_whitespace_p (ptrdiff_t charpos)
   int c = 0;
 
   while (bytepos < ZV_BYTE
-	 && (c = FETCH_CHAR (bytepos),
+	 && (c = FETCH_BYTE (bytepos),
 	     c == ' ' || c == '\t'))
     ++bytepos;