# HG changeset patch
# User Bram Moolenaar <Bram@vim.org>
# Date 1570385703 -7200
# Node ID 90284571606968ba1bd028d1e9dba33d87368db3
# Parent  4d15bd9b6829e14e6a1c4ab13aaa905c14df47eb
patch 8.1.2119: memory access error for empty string

Commit: https://github.com/vim/vim/commit/524f3b19ae16e08350010b5effe38d0637349285
Author: Bram Moolenaar <Bram@vim.org>
Date:   Sun Oct 6 20:08:38 2019 +0200

    patch 8.1.2119: memory access error for empty string

    Problem:    memory access error for empty string when 'encoding' is a single
                byte encoding.
    Solution:   Check for empty string when getting the length. (Dominique Pelle,
                closes #5021, closes #5007)

diff --git a/src/macros.h b/src/macros.h
--- a/src/macros.h
+++ b/src/macros.h
@@ -230,11 +230,11 @@
  * PTR2CHAR(): get character from pointer.
  */
 /* Get the length of the character p points to, including composing chars */
-#define MB_PTR2LEN(p)	    (has_mbyte ? (*mb_ptr2len)(p) : 1)
+#define MB_PTR2LEN(p)	    (has_mbyte ? (*mb_ptr2len)(p) : (*p == NUL ? 0 : 1))
 /* Advance multi-byte pointer, skip over composing chars. */
-#define MB_PTR_ADV(p)	    p += has_mbyte ? (*mb_ptr2len)(p) : 1
+#define MB_PTR_ADV(p)	    p += has_mbyte ? (*mb_ptr2len)(p) : (*p == NUL ? 0 : 1)
 /* Advance multi-byte pointer, do not skip over composing chars. */
-#define MB_CPTR_ADV(p)	    p += enc_utf8 ? utf_ptr2len(p) : has_mbyte ? (*mb_ptr2len)(p) : 1
+#define MB_CPTR_ADV(p)	    p += enc_utf8 ? utf_ptr2len(p) : has_mbyte ? (*mb_ptr2len)(p) : (*p == NUL ? 0 : 1)
 /* Backup multi-byte pointer. Only use with "p" > "s" ! */
 #define MB_PTR_BACK(s, p)  p -= has_mbyte ? ((*mb_head_off)(s, p - 1) + 1) : 1
 /* get length of multi-byte char, not including composing chars */
diff --git a/src/version.c b/src/version.c
--- a/src/version.c
+++ b/src/version.c
@@ -754,6 +754,8 @@ static char *(features[]) =
 static int included_patches[] =
 {   /* Add new patch number below this line */
 /**/
+    2119,
+/**/
     2118,
 /**/
     2117,