From 36f93678223be23747d90a393c9ba6c7cbe351c0 Mon Sep 17 00:00:00 2001
From: Vadim Zeitlin <vadim@wxwidgets.org>
Date: Thu, 17 Jul 2008 23:45:04 +0000
Subject: [PATCH] fix bug introduced in r54646: we still need to count the
embedded NULs when converting the entire NUL-terminated string to wchar_t,
only the trailing NUL shouldn't be counted
git-svn-id: https://svn.wxwidgets.org/svn/wx/wxWidgets/trunk@54673 c3d73ce0-8a6f-49c7-b76d-6d57e0e08775
---
src/common/strconv.cpp | 33 +++++++++++++++++++++++++++++++--
1 file changed, 31 insertions(+), 2 deletions(-)
diff --git a/src/common/strconv.cpp b/src/common/strconv.cpp
index 5d19539fc5..79ba45b9a1 100644
--- a/src/common/strconv.cpp
+++ b/src/common/strconv.cpp
@@ -160,11 +160,15 @@ wxMBConv::ToWChar(wchar_t *dst, size_t dstLen,
const char *src, size_t srcLen) const
{
// although new conversion classes are supposed to implement this function
- // directly, the existins ones only implement the old MB2WC() and so, to
+ // directly, the existing ones only implement the old MB2WC() and so, to
// avoid to have to rewrite all conversion classes at once, we provide a
// default (but not efficient) implementation of this one in terms of the
// old function by copying the input to ensure that it's NUL-terminated and
// then using MB2WC() to convert it
+ //
+ // moreover, some conversion classes simply can't implement ToWChar()
+ // directly, the primary example is wxConvLibc: mbstowcs() only handles
+ // NUL-terminated strings
// the number of chars [which would be] written to dst [if it were not NULL]
size_t dstWritten = 0;
@@ -205,6 +209,21 @@ wxMBConv::ToWChar(wchar_t *dst, size_t dstLen,
srcEnd = NULL;
}
+ // the idea of this code is straightforward: it converts a NUL-terminated
+ // chunk of the string during each iteration and updates the output buffer
+ // with the result
+ //
+ // all the complication come from the fact that this function, for
+ // historical reasons, must behave in 2 subtly different ways when it's
+ // called with a fixed number of characters and when it's called for the
+ // entire NUL-terminated string: in the former case (srcEnd == NULL) we
+ // must count all characters we convert, NUL or not; but in the latter we
+ // do not count the trailing NUL -- but still count all the NULs inside the
+ // string
+ //
+ // so for the (simple) former case we just always count the trailing NUL,
+ // but for the latter we need to wait until we see if there is going to be
+ // another loop iteration and only count it then
for ( ;; )
{
// try to convert the current chunk
@@ -257,9 +276,19 @@ wxMBConv::ToWChar(wchar_t *dst, size_t dstLen,
// note that ">=" (and not just "==") is needed here as the terminator
// we skipped just above could be inside or just after the buffer
- // delimited by inEnd
+ // delimited by srcEnd
if ( src >= srcEnd )
break;
+
+ // if we got here then this wasn't the last chunk in this string and
+ // hence we must count an extra char for L'\0' even when converting a
+ // fixed number of characters
+ if ( srcEnd )
+ {
+ dstWritten++;
+ if ( dst )
+ dst++;
+ }
}
return dstWritten;
--
2.47.2