Re: [PATCH v1 1/2] enter.c: Use wmem*() functions with wide-character strings

"Kevin J. McCarthy" <[email protected]> Fri, 13 Feb 2026 11:17:34 +0800
Newsgroups	gmane.mail.mutt.devel
Message-ID	<aY6Xzkl6V9kg_TRb@qinghai>
On Thu, Feb 12, 2026 at 11:56:19PM +0100, Alejandro Colomar via Mutt-dev wrote:
>This avoids an explicit size multiplication, which can overflow the
>calculation.

My concern is the conversation in the other thread about wc support, and 
portability, and --without-wc-funcs.  Otherwise this looks fine.

>diff --git a/enter.c b/enter.c
>index 54e81178b3c5..ba8b9963659c 100644
>--- a/enter.c
>+++ b/enter.c
>@@ -29,6 +29,7 @@
> #include "buffy.h"
>
> #include <string.h>
>+#include <wchar.h>

In mutt, this is already covered by #include "mutt.h".

> /* redraw flags for mutt_enter_string() */
> enum
>@@ -175,7 +176,7 @@ static void replace_part (ENTER_STATE *state, size_t from, char *buf)
>   if (savelen)
>   {
>     savebuf = safe_calloc (savelen, sizeof (wchar_t));
>-    memcpy (savebuf, state->wbuf + state->curpos, savelen * sizeof (wchar_t));
>+    wmemcpy (savebuf, state->wbuf + state->curpos, savelen);
>   }
>
>   /* Convert to wide characters */
>@@ -191,7 +192,7 @@ static void replace_part (ENTER_STATE *state, size_t from, char *buf)
>     }
>
>     /* Restore suffix */
>-    memcpy (state->wbuf + state->curpos, savebuf, savelen * sizeof (wchar_t));
>+    wmemcpy (state->wbuf + state->curpos, savebuf, savelen);
>     FREE (&savebuf);
>   }
>
>@@ -392,7 +393,7 @@ int _mutt_enter_string (char *buf, size_t buflen, int col,
>               --i;
>             if (i)
>               --i;
>-            memmove (state->wbuf + i, state->wbuf + state->curpos, (state->lastchar - state->curpos) * sizeof (wchar_t));
>+            wmemmove (state->wbuf + i, state->wbuf + state->curpos, state->lastchar - state->curpos);
>             state->lastchar -= state->curpos - i;
>             state->curpos = i;
>           }
>@@ -499,7 +500,7 @@ int _mutt_enter_string (char *buf, size_t buflen, int col,
>               ++i;
>             while (i < state->lastchar && COMB_CHAR (state->wbuf[i]))
>               ++i;
>-            memmove (state->wbuf + state->curpos, state->wbuf + i, (state->lastchar - i) * sizeof (wchar_t));
>+            wmemmove (state->wbuf + state->curpos, state->wbuf + i, state->lastchar - i);
>             state->lastchar -= i - state->curpos;
>           }
>           break;
>@@ -521,8 +522,8 @@ int _mutt_enter_string (char *buf, size_t buflen, int col,
>               else
>                 --i;
>             }
>-            memmove (state->wbuf + i, state->wbuf + state->curpos,
>-                     (state->lastchar - state->curpos) * sizeof (wchar_t));
>+            wmemmove (state->wbuf + i, state->wbuf + state->curpos,
>+                      state->lastchar - state->curpos);
>             state->lastchar += i - state->curpos;
>             state->curpos = i;
>           }
>@@ -553,8 +554,8 @@ int _mutt_enter_string (char *buf, size_t buflen, int col,
>             }
>           }
>
>-          memmove (state->wbuf + state->curpos, state->wbuf + i,
>-                   (state->lastchar - i) * sizeof (wchar_t));
>+          wmemmove (state->wbuf + state->curpos, state->wbuf + i,
>+                    state->lastchar - i);
>           state->lastchar += state->curpos - i;
>           break;
>
>@@ -580,7 +581,7 @@ int _mutt_enter_string (char *buf, size_t buflen, int col,
>               ;
>             my_wcstombs (buf, buflen, state->wbuf + i, state->curpos - i);
>             if (tempbuf && templen == state->lastchar - i &&
>-                !memcmp (tempbuf, state->wbuf + i, (state->lastchar - i) * sizeof (wchar_t)))
>+                !wmemcmp (tempbuf, state->wbuf + i, state->lastchar - i))
>             {
>               mutt_select_file (buf, buflen, 0);
>               if (*buf)
>@@ -593,7 +594,7 @@ int _mutt_enter_string (char *buf, size_t buflen, int col,
>               templen = state->lastchar - i;
>               safe_realloc (&tempbuf, templen * sizeof (wchar_t));
>               if (tempbuf)
>-                memcpy (tempbuf, state->wbuf + i, templen * sizeof (wchar_t));
>+                wmemcpy (tempbuf, state->wbuf + i, templen);
>             }
>             else
>               BEEP ();
>@@ -722,7 +723,7 @@ int _mutt_enter_string (char *buf, size_t buflen, int col,
>             /* see if the path has changed from the last time */
>             if ((!tempbuf && !state->lastchar) ||
>                 (tempbuf && templen == state->lastchar &&
>-                 !memcmp (tempbuf, state->wbuf, state->lastchar * sizeof (wchar_t))))
>+                 !wmemcmp (tempbuf, state->wbuf, state->lastchar)))
>             {
>               _mutt_select_file (buf, buflen,
>                                  ((flags & MUTT_MAILBOX) ? MUTT_SEL_MAILBOX : 0) | (multiple ? MUTT_SEL_MULTI : 0),
>@@ -751,7 +752,7 @@ int _mutt_enter_string (char *buf, size_t buflen, int col,
>               templen = state->lastchar;
>               safe_realloc (&tempbuf, templen * sizeof (wchar_t));
>               if (tempbuf)
>-                memcpy (tempbuf, state->wbuf, templen * sizeof (wchar_t));
>+                wmemcpy (tempbuf, state->wbuf, templen);
>             }
>             else
>               BEEP (); /* let the user know that nothing matched */
>@@ -875,7 +876,7 @@ self_insert:
>           state->wbuflen = state->lastchar + 20;
>           safe_realloc (&state->wbuf, state->wbuflen * sizeof (wchar_t));
>         }
>-        memmove (state->wbuf + state->curpos + 1, state->wbuf + state->curpos, (state->lastchar - state->curpos) * sizeof (wchar_t));
>+        wmemmove (state->wbuf + state->curpos + 1, state->wbuf + state->curpos, state->lastchar - state->curpos);
>         state->wbuf[state->curpos++] = wc;
>         state->lastchar++;
>       }
>-- 
>2.51.0
>

-- 
Kevin J. McCarthy
GPG Fingerprint: 8975 A9B3 3AA3 7910 385C  5308 ADEF 7684 8031 6BDA
signature.asc (application/pgp-signature, 833 B)