Patch 8.2.2515

[Bram Moolenaar]

Patch 8.2.2515
Problem: Memory access error when truncating an empty message.
Solution: Check for an empty string. (Dominique Pellé, closes #7841)
Files: src/message.c, src/message_test.c


*** ../vim-8.2.2514/src/message.c 2021-02-03 15:58:09.084690899 +0100
--- src/message.c 2021-02-14 15:36:04.553806035 +0100
***************
*** 248,253 ****
--- 248,260 ----
int i;
int n;

+ if (*s == NUL)
+ {
+ if (buflen > 0)
+ *buf = NUL;
+ return;
+ }
+
if (room_in < 3)
room = 0;
half = room / 2;
*** ../vim-8.2.2514/src/message_test.c 2020-04-20 16:12:06.039159143 +0200
--- src/message_test.c 2021-02-14 15:37:11.045652004 +0100
***************
*** 49,54 ****
--- 49,63 ----
char_u *buf; /*allocated every time to find uninit errors */
char_u *s;

+ // Should not write anything to destination if buflen is 0.
+ trunc_string((char_u *)"", NULL, 1, 0);
+
+ // Truncating an empty string does nothing.
+ buf = alloc(1);
+ trunc_string((char_u *)"", buf, 1, 1);
+ assert(buf[0] == NUL);
+ vim_free(buf);
+
// in place
buf = alloc(40);
STRCPY(buf, "text");
*** ../vim-8.2.2514/src/version.c 2021-02-14 14:07:31.369787927 +0100
--- src/version.c 2021-02-14 15:36:23.697761682 +0100
***************
*** 752,753 ****
--- 752,755 ----
{ /* Add new patch number below this line */
+ /**/
+ 2515,
/**/

--
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/// Bram Moolenaar -- Br...@Moolenaar.net -- http://www.Moolenaar.net \\\
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