From: Kevin McCarthy <kevin@8t8.us>
Date: Fri, 8 Apr 2016 22:27:17 +0000 (-0700)
Subject: Fix pager.c format_line() to use size_t for mbrtowc() retvals.
X-Git-Tag: neomutt-20160822~182
X-Git-Url: https://granicus.if.org/sourcecode?a=commitdiff_plain;h=f1faba947a75083a69d780117cf2aaeefd944909;p=neomutt

Fix pager.c format_line() to use size_t for mbrtowc() retvals.

While fixing up the error checking for mbrtowc(), I noticed the uses
in pager.c format_line() were assigning the retval to an int.

The cleanup for this was a little tricky, because it was making use of
possible negative values for (k1 - k).  The backspace detection loop
condition was a bit heavy, so this patch first pulled the
initialization and first call above, and put the second call inside
the loop.

Note that k1 previously included k, but this patch changes it to be
just the retval of mbrtowc.  This means the second mbrtowc() arguments
are changed to include k, as is the ch increment at the bottom of the
loop.
---

diff --git a/pager.c b/pager.c
index 9c26d873c..bc74578fa 100644
--- a/pager.c
+++ b/pager.c
@@ -1096,7 +1096,8 @@ static int format_line (struct line_t **lineInfo, int n, unsigned char *buf,
 {
   int space = -1; /* index of the last space or TAB */
   int col = option (OPTMARKERS) ? (*lineInfo)[n].continuation : 0;
-  int ch, vch, k, last_special = -1, special = 0, t;
+  size_t k;
+  int ch, vch, last_special = -1, special = 0, t;
   wchar_t wc;
   mbstate_t mbstate;
   int wrap_cols = mutt_term_width ((flags & M_PAGER_NOWRAP) ? 0 : Wrap);
@@ -1127,9 +1128,9 @@ static int format_line (struct line_t **lineInfo, int n, unsigned char *buf,
       break;
     
     k = mbrtowc (&wc, (char *)buf+ch, cnt-ch, &mbstate);
-    if (k == -2 || k == -1)
+    if (k == (size_t)(-2) || k == (size_t)(-1))
     {
-      if (k == -1)
+      if (k == (size_t)(-1))
         memset(&mbstate, 0, sizeof(mbstate));
       dprint (1, (debugfile, "%s:%d: mbrtowc returned %d; errno = %d.\n",
 		  __FILE__, __LINE__, k, errno));
@@ -1156,15 +1157,18 @@ static int format_line (struct line_t **lineInfo, int n, unsigned char *buf,
     {
       wchar_t wc1;
       mbstate_t mbstate1;
-      int k1, k2;
-
-      while ((wc1 = 0, mbstate1 = mbstate,
-	      k1 = k + mbrtowc (&wc1, (char *)buf+ch+k, cnt-ch-k, &mbstate1),
-	      k1 - k > 0 && wc1 == '\b') &&
-	     (wc1 = 0,
-	      k2 = mbrtowc (&wc1, (char *)buf+ch+k1, cnt-ch-k1, &mbstate1),
-	      k2 > 0 && IsWPrint (wc1)))
+      size_t k1, k2;
+
+      mbstate1 = mbstate;
+      k1 = mbrtowc (&wc1, (char *)buf+ch+k, cnt-ch-k, &mbstate1);
+      while ((k1 != (size_t)(-2)) && (k1 != (size_t)(-1)) &&
+             (k1 > 0) && (wc1 == '\b'))
       {
+        k2 = mbrtowc (&wc1, (char *)buf+ch+k+k1, cnt-ch-k-k1, &mbstate1);
+        if ((k2 == (size_t)(-2)) || (k2 == (size_t)(-1)) ||
+            (k2 == 0) || (!IsWPrint (wc1)))
+          break;
+
 	if (wc == wc1)
 	{
 	  special |= (wc == '_' && special & A_UNDERLINE)
@@ -1180,9 +1184,11 @@ static int format_line (struct line_t **lineInfo, int n, unsigned char *buf,
 	  /* special = 0; / * overstrike: nothing to do! */
 	  wc = wc1;
 	}
-	ch += k1;
+
+	ch += k + k1;
 	k = k2;
 	mbstate = mbstate1;
+        k1 = mbrtowc (&wc1, (char *)buf+ch+k, cnt-ch-k, &mbstate1);
       }
     }