Miscellaneous Unicode bugfixes and optimizations

libraries/emulatorview/src/jackpal/androidterm/emulatorview/PaintRenderer.java

@@ -67,10 +67,11 @@ public void drawTextRun(Canvas canvas, float x, float y, int lineOffset,
                 left + runWidth * mCharWidth, y,
                 mTextPaint);
 
-        boolean cursorVisible = index <= cursorOffset && cursorOffset < (index + count);
+        boolean cursorVisible = lineOffset <= cursorOffset && cursorOffset < (lineOffset + runWidth);
+        float cursorX = 0;
         if (cursorVisible) {
-            int cursorX = (int) (x + cursorOffset * mCharWidth);
-            drawCursorImp(canvas, cursorX, y, cursorWidth * mCharWidth, mCharHeight, cursorMode);
+            cursorX = x + cursorOffset * mCharWidth;
+            drawCursorImp(canvas, (int) cursorX, y, cursorWidth * mCharWidth, mCharHeight, cursorMode);
         }
 
         boolean invisible = (effect & TextStyle.fxInvisible) != 0;
@@ -97,19 +98,19 @@ public void drawTextRun(Canvas canvas, float x, float y, int lineOffset,
             if (cursorVisible) {
                 // Text before cursor
                 int countBeforeCursor = cursorIndex - index;
-                int countAfterCursor = count - (countBeforeCursor + 1);
+                int countAfterCursor = count - (countBeforeCursor + cursorIncr);
                 if (countBeforeCursor > 0){
                     canvas.drawText(text, index, countBeforeCursor, left, textOriginY, mTextPaint);
                 }
                 // Text at cursor
                 mTextPaint.setColor(mPalette[TextStyle.ciCursorForeground]);
-                canvas.drawText(text, cursorIndex, cursorIncr, x + cursorOffset * mCharWidth,
+                canvas.drawText(text, cursorIndex, cursorIncr, cursorX,
                         textOriginY, mTextPaint);
                 // Text after cursor
                 if (countAfterCursor > 0) {
                     mTextPaint.setColor(textPaintColor);
                     canvas.drawText(text, cursorIndex + cursorIncr, countAfterCursor,
-                            x + (cursorOffset + cursorWidth) * mCharWidth,
+                            cursorX + cursorWidth * mCharWidth,
                             textOriginY, mTextPaint);
                 }
             } else {

libraries/emulatorview/src/jackpal/androidterm/emulatorview/TermSession.java

@@ -290,8 +290,16 @@ public void write(String data) {
      * @param codePoint The Unicode code point to write to the terminal.
      */
     public void write(int codePoint) {
-        CharBuffer charBuf = mWriteCharBuffer;
         ByteBuffer byteBuf = mWriteByteBuffer;
+        if (codePoint < 128) {
+            // Fast path for ASCII characters
+            byte[] buf = byteBuf.array();
+            buf[0] = (byte) codePoint;
+            write(buf, 0, 1);
+            return;
+        }
+
+        CharBuffer charBuf = mWriteCharBuffer;
         CharsetEncoder encoder = mUTF8Encoder;
 
         charBuf.clear();

libraries/emulatorview/src/jackpal/androidterm/emulatorview/TerminalEmulator.java

@@ -823,7 +823,11 @@ private boolean handleUTF8Sequence(byte b) {
                 mUTF8ToFollow = 0;
                 mUTF8ByteBuffer.clear();
                 emit(UNICODE_REPLACEMENT_CHAR);
-                return true;
+
+                /* The Unicode standard (section 3.9, definition D93) requires
+                 * that we now attempt to process this byte as though it were
+                 * the beginning of another possibly-valid sequence */
+                return handleUTF8Sequence(b);
             }
 
             mUTF8ByteBuffer.put(b);

libraries/emulatorview/src/jackpal/androidterm/emulatorview/TranscriptScreen.java

@@ -204,19 +204,20 @@ public final void drawText(int row, Canvas canvas, float x, float y,
         }
 
         int columns = mColumns;
+        int lineLen = line.length;
         int lastStyle = 0;
         boolean lastSelectionStyle = false;
         int runWidth = 0;
         int lastRunStart = -1;
         int lastRunStartIndex = -1;
         boolean forceFlushRun = false;
         int column = 0;
+        int nextColumn = 0;
+        int displayCharWidth = 0;
         int index = 0;
         int cursorIndex = 0;
         int cursorIncr = 0;
-        while (column < columns) {
-            int style = color.get(column);
-            boolean selectionStyle = false;
+        while (column < columns && index < lineLen && line[index] != '\0') {
             int incr = 1;
             int width;
             if (Character.isHighSurrogate(line[index])) {
@@ -225,7 +226,15 @@ public final void drawText(int row, Canvas canvas, float x, float y,
             } else {
                 width = UnicodeTranscript.charWidth(line[index]);
             }
-            if (column >= selx1 && column <= selx2) {
+            if (width > 0) {
+                // We've moved on to the next column
+                column = nextColumn;
+                displayCharWidth = width;
+            }
+            int style = color.get(column);
+            boolean selectionStyle = false;
+            if ((column >= selx1 || (displayCharWidth == 2 && column == selx1 - 1)) &&
+                    column <= selx2) {
                 // Draw selection:
                 selectionStyle = true;
             }
@@ -247,12 +256,17 @@ public final void drawText(int row, Canvas canvas, float x, float y,
                 forceFlushRun = false;
             }
             if (cx == column) {
-                cursorIndex = index;
-                cursorIncr = incr;
-                cursorWidth = width;
+                if (width > 0) {
+                    cursorIndex = index;
+                    cursorIncr = incr;
+                    cursorWidth = width;
+                } else {
+                    // Combining char attaching to the char under the cursor
+                    cursorIncr += incr;
+                }
             }
             runWidth += width;
-            column += width;
+            nextColumn += width;
             index += incr;
             if (width > 1) {
                 /* We cannot draw two or more East Asian wide characters in the
@@ -357,13 +371,24 @@ private String internalGetTranscriptText(GrowableIntArray colors, int selX1, int
             int lastPrintingChar = -1;
             int lineLen = line.length;
             int i;
-            int width = x2 - x1;
             int column = 0;
-            for (i = 0; i < lineLen && column < width; ++i) {
+            for (i = 0; i < lineLen; ++i) {
                 char c = line[i];
                 if (c == 0) {
                     break;
-                } else if (c != ' ' || ((rowColorBuffer != null) && (rowColorBuffer.get(column) != defaultColor))) {
+                }
+
+                int style = defaultColor;
+                try {
+                    if (rowColorBuffer != null) {
+                        style = rowColorBuffer.get(column);
+                    }
+                } catch (ArrayIndexOutOfBoundsException e) {
+                    // XXX This probably shouldn't happen ...
+                    style = defaultColor;
+                }
+
+                if (c != ' ' || style != defaultColor) {
                     lastPrintingChar = i;
                 }
                 if (!Character.isLowSurrogate(c)) {