Fix display of Unicode text in many views

This commit also adds the strwidth function and consolidates the TDrawBuffer interface.

include/tvision/drawbuf.h

@@ -42,6 +42,7 @@ class TDrawBuffer
 
     void moveChar( ushort indent, char c, ushort attr, ushort count );
     void moveStr( ushort indent, const char _FAR *str, ushort attrs );
+    void moveStr( ushort indent, const char _FAR *str, ushort attr, ushort width, ushort begin=0 );
     void moveCStr( ushort indent, const char _FAR *str, ushort attrs );
     void moveBuf( ushort indent, const void _FAR *source,
                   ushort attr, ushort count );
@@ -52,10 +53,10 @@ class TDrawBuffer
 
 #ifndef __BORLANDC__
     // Multibyte compatible operations
-
-    void moveStrEx( ushort indent, std::string_view str, ushort attrs );
-    void moveCStrEx( ushort indent, std::string_view str, ushort attrs );
-    void moveBufEx( ushort indent, TScreenCell *source, ushort attr, ushort count );
+    void moveStr( ushort indent, std::string_view str, ushort attrs );
+    void moveStr( ushort indent, std::string_view str, ushort attr, ushort width, ushort begin=0 );
+    void moveCStr( ushort indent, std::string_view str, ushort attrs );
+    void moveBuf( ushort indent, TScreenCell *source, ushort attr, ushort count );
 #endif
 
 #ifdef __FLAT__

include/tvision/util.h

@@ -45,8 +45,10 @@ const char *historyStr( uchar id, int index );
 void historyAdd( uchar id, const char * );
 
 int cstrlen( const char * );
+int strwidth( const char * );
 #ifndef __BORLANDC__
-int cstrlen(std::string_view s);
+int cstrlen( std::string_view s );
+int strwidth( std::string_view s );
 #endif
 
 class _FAR TView;
@@ -67,7 +69,7 @@ void getCurDir( char *dir );
 
 Boolean isWild( const char *f );
 
-char *strnzcpy( char *dest, const char *src, size_t n ); // misc.cpp
+char *strnzcpy( char *dest, const char *src, size_t n );
 
 unsigned int fast_utoa( uint value, char *buffer );
 

source/tvision/drivers.cpp

@@ -113,28 +113,12 @@ I   POP     DS
             *(uchar *)dest++ = *s++;
 
 #else
-    return moveStrEx(indent, std::string_view {(const char*) source, count}, attr);
-#if 0
-    TScreenCell *dest = &data[indent];
-    TScreenCell *limit = &data[dataLength];
-    uchar *s = (uchar *) source;
-    if (attr)
-        for (; dest < limit && count; --count, ++s, ++dest)
-        {
-            TScreenCell c {};
-            c.Char = (uchar) *s;
-            c.Attr = (uchar) attr;
-            *dest = c;
-        }
-    else
-        while (dest < limit && count--)
-            *dest++ = TScreenCell::fromPair(*s++);
-#endif
+    return moveStr(indent, std::string_view {(const char*) source, count}, attr);
 #endif
 }
 
 #ifndef __BORLANDC__
-void TDrawBuffer::moveBufEx(ushort indent, TScreenCell *source, ushort attr, ushort count)
+void TDrawBuffer::moveBuf(ushort indent, TScreenCell *source, ushort attr, ushort count)
 {
     TScreenCell *dest = &data[indent];
     TScreenCell *limit = &data[dataLength];
@@ -317,35 +301,12 @@ I   POP     DS
             }
         }
 #else
-    return moveCStrEx(indent, str, attrs);
-#if 0
-    TScreenCell *dest = &data[indent];
-    TScreenCell *limit = &data[dataLength];
-    uchar c;
-    int toggle = 1;
-    uchar curAttr = ((uchar *)&attrs)[0];
-
-    for (; dest < limit && (c = *str); ++str)
-    {
-        if (c == '~')
-        {
-            curAttr = ((uchar *) &attrs)[toggle];
-            toggle = 1 - toggle;
-        }
-        else
-        {
-            TScreenCell cell {};
-            cell.Char = (uchar) c;
-            cell.Attr = (uchar) curAttr;
-            *dest++ = cell;
-        }
-    }
-#endif
+    return moveCStr(indent, std::string_view {str}, attrs);
 #endif
 }
 
 #ifndef __BORLANDC__
-void TDrawBuffer::moveCStrEx( ushort indent, std::string_view str, ushort attrs )
+void TDrawBuffer::moveCStr( ushort indent, std::string_view str, ushort attrs )
 {
     size_t i = indent, j = 0;
     int toggle = 1;
@@ -434,34 +395,12 @@ I   POP     DS
             while (dest < limit && *str)
                 *(uchar *)dest++ = *str++;
 #else
-    return moveStrEx(indent, str, attr);
-#if 0
-    TScreenCell *dest = &data[indent];
-    TScreenCell *limit = &data[dataLength];
-    uchar c;
-
-    if (attr)
-        for (; dest < limit && (c = *str); ++str, ++dest)
-        {
-            TScreenCell cell {};
-            cell.Char = (uchar) c;
-            cell.Attr = (uchar) attr;
-            *dest = cell;
-        }
-    else
-        while (dest < limit && *str)
-        {
-            auto cell = dest->Cell;
-            cell.Char = (uchar) *str++;
-            cell.extraWidth = 0;
-            *dest++ = cell;;
-        }
-#endif
+    return moveStr(indent, std::string_view {str}, attr);
 #endif
 }
 
 #ifndef __BORLANDC__
-void TDrawBuffer::moveStrEx( ushort indent, std::string_view str, ushort attr )
+void TDrawBuffer::moveStr( ushort indent, std::string_view str, ushort attr )
 {
     size_t i = indent, j = 0;
 
@@ -477,6 +416,59 @@ void TDrawBuffer::moveStrEx( ushort indent, std::string_view str, ushort attr )
 }
 #endif
 
+/*------------------------------------------------------------------------*/
+/*                                                                        */
+/*  TDrawBuffer::moveStr (2)                                              */
+/*                                                                        */
+/*  arguments:                                                            */
+/*                                                                        */
+/*      indent  - character position within the buffer where the data     */
+/*                is to go                                                */
+/*                                                                        */
+/*      str     - pointer to a 0-terminated string of characters to       */
+/*                be moved into the buffer                                */
+/*                                                                        */
+/*      attr    - text attribute to be put into the buffer with each      */
+/*                character in the string.                                */
+/*                                                                        */
+/*      width   - number of display columns to be copied from str.        */
+/*                                                                        */
+/*      begin   - initial display column in str where to start counting.  */
+/*                                                                        */
+/*------------------------------------------------------------------------*/
+
+void TDrawBuffer::moveStr( ushort indent, const char _FAR *str, ushort attr, ushort width, ushort begin )
+{
+#ifdef __BORLANDC__
+    int len = 0;
+    while (str[len] && len < int(begin + width))
+        ++len;
+    len -= begin;
+    if (len > 0)
+        moveBuf(indent, str + begin, attr, min(width, len));
+#else
+    moveStr(indent, std::string {str}, attr, width, begin);
+#endif
+}
+
+#ifndef __BORLANDC__
+void TDrawBuffer::moveStr( ushort indent, std::string_view str, ushort attr, ushort width, ushort begin )
+{
+    size_t s = 0, remainder = 0;
+    utf8wseek(str, s, remainder, begin);
+    if (remainder)
+        moveChar(indent, ' ', attr, remainder);
+    size_t d = indent + remainder;
+    size_t limit = std::min(dataLength, d + width);
+    while (d < limit && s < str.size())
+    {
+        if (attr)
+            data[d].Attr = (uchar) attr;
+        utf8read(&data[d], dataLength - d, d, {&str[s], str.size() - s}, s);
+    }
+}
+#endif
+
 #ifdef __FLAT__
 TDrawBuffer::TDrawBuffer() {
     // This makes it possible to create TDrawBuffers for big screen widths.

source/tvision/drivers2.cpp

@@ -74,16 +74,16 @@ const ushort arrowCodes[] =
 
 int cstrlen( const char *s )
 {
-#ifndef __BORLANDC__
-    return cstrlen(std::string_view {s});
-#else
+#ifdef __BORLANDC__
     int len = 0;
     while( *s != EOS )
         {
         if( *s++ != '~' )
             len++;
         }
     return len;
+#else
+    return cstrlen(std::string_view {s});
 #endif
 }
 
@@ -101,3 +101,37 @@ int cstrlen( std::string_view s )
     return width;
 }
 #endif
+
+/*------------------------------------------------------------------------*/
+/*                                                                        */
+/*  strwidth                                                              */
+/*                                                                        */
+/*  argument:                                                             */
+/*                                                                        */
+/*      s       - pointer to 0-terminated string                          */
+/*                                                                        */
+/*  returns                                                               */
+/*                                                                        */
+/*      displayed length of string.                                       */
+/*                                                                        */
+/*------------------------------------------------------------------------*/
+
+int strwidth( const char *s )
+{
+#ifdef __BORLANDC__
+    return strlen(s);
+#else
+    return strwidth(std::string_view {s});
+#endif
+}
+
+#ifndef __BORLANDC__
+int strwidth( std::string_view s )
+{
+    std::mbstate_t state = {};
+    size_t i = 0, width = 0;
+    while (i < s.size())
+        utf8next(s.substr(i, s.size() - i), i, width, state);
+    return width;
+}
+#endif

source/tvision/help.cpp

@@ -94,8 +94,6 @@ void THelpViewer::draw()
     TDrawBuffer b;
     size_t bufLength = b.length();
     char *line = (char*) alloca(bufLength);
-    char *buffer = (char*) alloca(bufLength);
-    char *bufPtr;
     int i, j, l;
     int keyCount;
     ushort normal, keyword, selKeyword, c;
@@ -122,13 +120,11 @@ void THelpViewer::draw()
     for (i = 1; i <= size.y; ++i)
         {
         b.moveChar(0, ' ', normal, size.x);
-        strcpy(line, topic->getLine(i + delta.y, buffer, bufLength));
-        if (strlen(line) > delta.x)
+        memset(line, 0, bufLength);
+        topic->getLine(i + delta.y, line, bufLength-1);
+        if (strwidth(line) > delta.x)
             {
-            bufPtr = line + delta.x;
-            strncpy(buffer, bufPtr, size.x);
-            buffer[size.x] = 0;
-            b.moveStr(0, buffer, normal);
+            b.moveStr(0, line, normal, size.x, delta.x);
             }
         else
             b.moveStr(0, "", normal);

source/tvision/tframe.cpp

@@ -87,7 +87,7 @@ void TFrame::draw()
             l = max( l, 0 );
             i = (width - l) >> 1;
             b.putChar( i-1, ' ' );
-            b.moveBuf( i, title, cTitle, l );
+            b.moveStr( i, title, cTitle, l );
             b.putChar( i+l, ' ' );
             }
         }

source/tvision/thstview.cpp

@@ -90,7 +90,7 @@ int THistoryViewer::historyWidth()
     int count = historyCount( historyId );
     for( int i = 0; i < count; i++ )
         {
-        int T = strlen( historyStr( historyId, i ) );
+        int T = strwidth( historyStr( historyId, i ) );
         width = max( width, T );
         }
     return width;

source/tvision/tinputli.cpp

@@ -77,7 +77,7 @@ Boolean TInputLine::canScroll( int delta )
         return Boolean( firstPos > 0 );
     else
         if( delta > 0 )
-            return Boolean( strlen(data) - firstPos + 2 > size.x );
+            return Boolean( strwidth(data) - firstPos + 2 > size.x );
         else
             return False;
 }
@@ -103,10 +103,7 @@ void TInputLine::draw()
     b.moveChar( 0, ' ', color, size.x );
     if( size.x > 1 )
         {
-        char buf[256];
-        strncpy( buf, data+firstPos, size.x - 2 );
-        buf[size.x - 2 ] = EOS;
-        b.moveStr( 1, buf, color );
+        b.moveStr( 1, data, color, size.x - 1, firstPos);
         }
     if( canScroll(1) )
         b.moveChar( size.x-1, rightArrow, getColor(4), 1 );
@@ -317,8 +314,6 @@ void TInputLine::handleEvent( TEvent& event )
                             {
                             strcpy( data+curPos-1, data+curPos );
                             curPos--;
-                            if( firstPos > 0 )
-                                firstPos--;
                             checkValid(True);
                             }
                         break;

source/tvision/tlstview.cpp

@@ -131,8 +131,8 @@ void TListViewer::draw()
                 if (indent < 255)
                     {
                     char text[256] = {0};
-                    getText( text, item, min(colWidth + indent, 255) );
-                    b.moveStr( curCol+1, text + indent, color );
+                    getText( text, item, 255 );
+                    b.moveStr( curCol+1, text, color, colWidth, indent );
                     }
                 if( showMarkers )
                     {

source/tvision/tmenubox.cpp

@@ -37,7 +37,7 @@ static TRect getRect( const TRect& bounds, TMenu *aMenu )
                     l += 3;
                 else
                     if( p->param != 0 )
-                        l += cstrlen(p->param) + 2;
+                        l += strwidth(p->param) + 2;
                 w = max( l, w );
                 }
             h++;
@@ -110,7 +110,7 @@ void TMenuBox::draw()
                 if( p->command == 0 )
                     b.putChar( size.x-4, 16 );
                 else if( p->param != 0 )
-                    b.moveStr( size.x-3-strlen(p->param),
+                    b.moveStr( size.x-3-strwidth(p->param),
                                p->param,
                                color);
                 }