Added changeable attribute to styles that defaults to true. When it is

false, text in this style is read only.

6 files changed, 27 insertions, 9 deletions

diff --git a/include/Scintilla.h b/include/Scintilla.h
index 20c5f267a..2a51f84f6 100644
--- a/include/Scintilla.h
+++ b/include/Scintilla.h
@@ -205,6 +205,7 @@ typedef sptr_t (*SciFnDirect)(sptr_t ptr, unsigned int iMessage, uptr_t wParam,
 #define SCI_SETCARETLINEVISIBLE 2096
 #define SCI_GETCARETLINEBACK 2097
 #define SCI_SETCARETLINEBACK 2098
+#define SCI_STYLESETCHANGEABLE 2099
 #define SCI_AUTOCSHOW 2100
 #define SCI_AUTOCCANCEL 2101
 #define SCI_AUTOCACTIVE 2102
diff --git a/include/Scintilla.iface b/include/Scintilla.iface
index 9e30673d7..d83c71321 100644
--- a/include/Scintilla.iface
+++ b/include/Scintilla.iface
@@ -472,6 +472,9 @@ get colour GetCaretLineBack=2097(,)
 # Set the colour of the background of the line containing the caret.
 set void SetCaretLineBack=2098(colour back,)
 
+# Set a style to be changeable or not (read only).
+set void StyleSetChangeable=2099(int style, bool changeable)
+
 # Display a auto-completion list.
 # The lenEntered parameter indicates how many characters before
 # the caret should be used to provide context.
diff --git a/src/Editor.cxx b/src/Editor.cxx
index 1f7588a28..439e1388d 100644
--- a/src/Editor.cxx
+++ b/src/Editor.cxx
@@ -549,11 +549,11 @@ int Editor::MovePositionOutsideChar(int pos, int moveDir, bool checkLineEnd) {
 	int mask = pdoc->stylingBitsMask;
 	if (moveDir > 0) {
 		while ((pos < pdoc->Length()) &&
-		        (!vs.styles[pdoc->StyleAt(pos - 1) & mask].visible))
+		        (vs.styles[pdoc->StyleAt(pos - 1) & mask].IsProtected()))
 			pos++;
 	} else {
 		while ((pos > 0) &&
-		        (!vs.styles[pdoc->StyleAt(pos - 1) & mask].visible))
+		        (vs.styles[pdoc->StyleAt(pos - 1) & mask].IsProtected()))
 			pos--;
 	}
 	return pos;
@@ -4542,6 +4542,12 @@ sptr_t Editor::WndProc(unsigned int iMessage, uptr_t wParam, sptr_t lParam) {
 			InvalidateStyleRedraw();
 		}
 		break;
+	case SCI_STYLESETCHANGEABLE:
+		if (wParam <= STYLE_MAX) {
+			vs.styles[wParam].changeable = lParam;
+			InvalidateStyleRedraw();
+		}
+		break;
 
 	case SCI_STYLERESETDEFAULT:
 		vs.ResetDefaultStyle();
diff --git a/src/Style.cxx b/src/Style.cxx
index 5989dae80..2ee09f57d 100644
--- a/src/Style.cxx
+++ b/src/Style.cxx
@@ -16,13 +16,13 @@ Style::Style() {
 	aliasOfDefaultFont = true;
 	Clear(ColourDesired(0, 0, 0), ColourDesired(0xff, 0xff, 0xff),
 	      Platform::DefaultFontSize(), 0, SC_CHARSET_DEFAULT,
-	      false, false, false, false, caseMixed, true);
+	      false, false, false, false, caseMixed, true, true);
 }
 
 Style::Style(const Style &source) {
 	Clear(ColourDesired(0, 0, 0), ColourDesired(0xff, 0xff, 0xff),
 	      0, 0, 0,
-	      false, false, false, false, caseMixed, true);
+	      false, false, false, false, caseMixed, true, true);
 	fore.desired = source.fore.desired;
 	back.desired = source.back.desired;
 	characterSet = source.characterSet;
@@ -33,6 +33,7 @@ Style::Style(const Style &source) {
 	underline = source.underline;
 	caseForce = source.caseForce;
 	visible = source.visible;
+	changeable = source.changeable;
 }
 
 Style::~Style() {
@@ -48,7 +49,7 @@ Style &Style::operator=(const Style &source) {
 		return * this;
 	Clear(ColourDesired(0, 0, 0), ColourDesired(0xff, 0xff, 0xff),
 	      0, 0, SC_CHARSET_DEFAULT,
-	      false, false, false, false, caseMixed, true);
+	      false, false, false, false, caseMixed, true, true);
 	fore.desired = source.fore.desired;
 	back.desired = source.back.desired;
 	characterSet = source.characterSet;
@@ -59,13 +60,15 @@ Style &Style::operator=(const Style &source) {
 	underline = source.underline;
 	caseForce = source.caseForce;
 	visible = source.visible;
+	changeable = source.changeable;
 	return *this;
 }
 
 void Style::Clear(ColourDesired fore_, ColourDesired back_, int size_,
                   const char *fontName_, int characterSet_,
                   bool bold_, bool italic_, bool eolFilled_, 
-                  bool underline_, ecaseForced caseForce_, bool visible_) {
+                  bool underline_, ecaseForced caseForce_, 
+		  bool visible_, bool changeable_) {
 	fore.desired = fore_;
 	back.desired = back_;
 	characterSet = characterSet_;
@@ -77,6 +80,7 @@ void Style::Clear(ColourDesired fore_, ColourDesired back_, int size_,
 	underline = underline_;
 	caseForce = caseForce_;
 	visible = visible_;
+	changeable = changeable_;
 	if (aliasOfDefaultFont)
 		font.SetID(0);
 	else
@@ -96,7 +100,8 @@ void Style::ClearTo(const Style &source) {
 		source.eolFilled,
 		source.underline,
 		source.caseForce,
-		source.visible);
+		source.visible, 
+		source.changeable);
 }
 
 bool Style::EquivalentFontTo(const Style *other) const {
diff --git a/src/Style.h b/src/Style.h
index 17d32ac33..63259b1a9 100644
--- a/src/Style.h
+++ b/src/Style.h
@@ -25,6 +25,7 @@ public:
 	enum ecaseForced {caseMixed, caseUpper, caseLower};
 	ecaseForced caseForce;
 	bool visible;
+	bool changeable;
 
 	Font font;
 	int sizeZoomed;
@@ -43,10 +44,12 @@ public:
 	           int size_,
 	           const char *fontName_, int characterSet_,
 	           bool bold_, bool italic_, bool eolFilled_, 
-	           bool underline_, ecaseForced caseForce_, bool visible_);
+	           bool underline_, ecaseForced caseForce_, 
+		   bool visible_, bool changeable_);
 	void ClearTo(const Style &source);
 	bool EquivalentFontTo(const Style *other) const;
 	void Realise(Surface &surface, int zoomLevel, Style *defaultStyle = 0);
+	bool IsProtected() { return !(changeable && visible);} ;
 };
 
 #endif
diff --git a/src/ViewStyle.cxx b/src/ViewStyle.cxx
index 40615da65..7937e1fca 100644
--- a/src/ViewStyle.cxx
+++ b/src/ViewStyle.cxx
@@ -219,7 +219,7 @@ void ViewStyle::ResetDefaultStyle() {
 		ColourDesired(0xff,0xff,0xff),
 	        Platform::DefaultFontSize(), fontNames.Save(Platform::DefaultFont()),
 		SC_CHARSET_DEFAULT,
-		false, false, false, false, Style::caseMixed, true);
+		false, false, false, false, Style::caseMixed, true, true);
 }
 
 void ViewStyle::ClearStyles() {