X-Git-Url: https://git.saurik.com/wxWidgets.git/blobdiff_plain/852dcba5286b2b423d7cb21799d11df7efcbd0e6..bf9ce2abdf465110ca83469c1b336b056ae8ec72:/src/common/strconv.cpp

diff --git a/src/common/strconv.cpp b/src/common/strconv.cpp
index 5d19539fc5..31dc602f35 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;
@@ -536,7 +565,7 @@ static const unsigned char utf7unb64[] =
     0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff,
     0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff,
     0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff,
-    0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff 
+    0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff
 };
 
 size_t wxMBConvUTF7::ToWChar(wchar_t *dst, size_t dstLen,
@@ -580,11 +609,19 @@ size_t wxMBConvUTF7::ToWChar(wchar_t *dst, size_t dstLen,
             const unsigned char dc = utf7unb64[cc];
             if ( dc == 0xff )
             {
-                // end of encoded part, check that nothing was left: the bit
-                // field cycles through 0,6,4,2 sequence so check that we're at
-                // the end of it
-                if ( state.bit != 2 )
+                // end of encoded part, check that nothing was left: there can
+                // be up to 4 bits of 0 padding but nothing else (we also need
+                // to check isLSB as we count bits modulo 8 while a valid UTF-7
+                // encoded sequence must contain an integral number of UTF-16
+                // characters)
+                if ( state.isLSB || state.bit > 4 ||
+                        (state.accum & ((1 << state.bit) - 1)) )
+                {
+                    if ( !len )
+                        state = stateOrig;
+
                     return wxCONV_FAILED;
+                }
 
                 state.ToDirect();
 
@@ -637,7 +674,15 @@ size_t wxMBConvUTF7::ToWChar(wchar_t *dst, size_t dstLen,
                     len++;
                     src++;
                 }
-                else
+                else if ( utf7unb64[(unsigned)*src] == 0xff )
+                {
+                    // empty encoded chunks are not allowed
+                    if ( !len )
+                        state = stateOrig;
+
+                    return wxCONV_FAILED;
+                }
+                else // base-64 encoded chunk follows
                 {
                     state.ToShifted();
                 }
@@ -2845,6 +2890,16 @@ wxCSConv::wxCSConv(const wxString& charset)
 
 #if wxUSE_FONTMAP
     m_encoding = wxFontMapperBase::GetEncodingFromName(charset);
+    if ( m_encoding == wxFONTENCODING_MAX )
+    {
+        // set to unknown/invalid value
+        m_encoding = wxFONTENCODING_SYSTEM;
+    }
+    else if ( m_encoding == wxFONTENCODING_DEFAULT )
+    {
+        // wxFONTENCODING_DEFAULT is same as US-ASCII in this context
+        m_encoding = wxFONTENCODING_ISO8859_1;
+    }
 #else
     m_encoding = wxFONTENCODING_SYSTEM;
 #endif