Refactored the mutex usage in osgText and freetype plugin to prevent multi-thread crash

src/osgPlugins/freetype/FreeTypeFont.cpp

@@ -97,7 +97,7 @@ void FreeTypeFont::setFontResolution(const osgText::FontResolution& fontSize)
 
 osgText::Font::Glyph* FreeTypeFont::getGlyph(const osgText::FontResolution& fontRes, unsigned int charcode)
 {
-    OpenThreads::ScopedLock<OpenThreads::Mutex> lock(_mutex);
+    OpenThreads::ScopedLock<OpenThreads::Mutex> lock(FreeTypeLibrary::instance()->getMutex());
 
     setFontResolution(fontRes);
 
@@ -201,7 +201,7 @@ osgText::Font::Glyph* FreeTypeFont::getGlyph(const osgText::FontResolution& font
 
 osg::Vec2 FreeTypeFont::getKerning(const osgText::FontResolution& fontRes, unsigned int leftcharcode,unsigned int rightcharcode, osgText::KerningType kerningType)
 {
-    OpenThreads::ScopedLock<OpenThreads::Mutex> lock(_mutex);
+    OpenThreads::ScopedLock<OpenThreads::Mutex> lock(FreeTypeLibrary::instance()->getMutex());
 
     if (!FT_HAS_KERNING(_face) || (kerningType == osgText::KERNING_NONE)) return osg::Vec2(0.0f,0.0f);
 
@@ -233,5 +233,6 @@ osg::Vec2 FreeTypeFont::getKerning(const osgText::FontResolution& fontRes, unsig
 
 bool FreeTypeFont::hasVertical() const
 {
+    OpenThreads::ScopedLock<OpenThreads::Mutex> lock(FreeTypeLibrary::instance()->getMutex());
     return FT_HAS_VERTICAL(_face)!=0;
 }

src/osgPlugins/freetype/FreeTypeFont.h

@@ -41,7 +41,6 @@ protected:
 
     void setFontResolution(const osgText::FontResolution& fontSize);
 
-    OpenThreads::Mutex      _mutex;
     osgText::FontResolution _currentRes;
 
     std::string             _filename;

src/osgPlugins/freetype/FreeTypeLibrary.cpp

@@ -69,6 +69,8 @@ FreeTypeLibrary* FreeTypeLibrary::instance()
 
 bool FreeTypeLibrary::getFace(const std::string& fontfile,unsigned int index, FT_Face & face)
 {
+    OpenThreads::ScopedLock<OpenThreads::Mutex> lock(getMutex());
+
     FT_Error error = FT_New_Face( _ftlibrary, fontfile.c_str(), index, &face );
     if (error == FT_Err_Unknown_File_Format)
     {
@@ -110,6 +112,8 @@ bool FreeTypeLibrary::getFace(const std::string& fontfile,unsigned int index, FT
 
 FT_Byte* FreeTypeLibrary::getFace(std::istream& fontstream, unsigned int index, FT_Face & face)
 {
+    OpenThreads::ScopedLock<OpenThreads::Mutex> lock(getMutex());
+
     FT_Open_Args args;
 
     std::streampos start = fontstream.tellg();
@@ -159,6 +163,7 @@ osgText::Font* FreeTypeLibrary::getFont(const std::string& fontfile, unsigned in
     FT_Face face;
     if (getFace(fontfile, index, face) == false) return (0);
 
+    OpenThreads::ScopedLock<OpenThreads::Mutex> lock(getMutex());
     
     FreeTypeFont* fontImp = new FreeTypeFont(fontfile,face,flags);
     osgText::Font* font = new osgText::Font(fontImp);
@@ -174,6 +179,8 @@ osgText::Font* FreeTypeLibrary::getFont(std::istream& fontstream, unsigned int i
     if (face == 0) return (0);
 
     
+    OpenThreads::ScopedLock<OpenThreads::Mutex> lock(getMutex());
+
     FreeTypeFont* fontImp = new FreeTypeFont(buffer,face,flags);
     osgText::Font* font = new osgText::Font(fontImp);
     
@@ -187,6 +194,7 @@ osgText::Font3D* FreeTypeLibrary::getFont3D(const std::string& fontfile, unsigne
     FT_Face face;
     if (getFace(fontfile, index, face) == false) return (0);
 
+    OpenThreads::ScopedLock<OpenThreads::Mutex> lock(getMutex());
     
     FreeTypeFont3D* font3DImp = new FreeTypeFont3D(fontfile,face,flags);
     osgText::Font3D* font3D = new osgText::Font3D(font3DImp);
@@ -197,11 +205,13 @@ osgText::Font3D* FreeTypeLibrary::getFont3D(const std::string& fontfile, unsigne
 }
 osgText::Font3D* FreeTypeLibrary::getFont3D(std::istream& fontstream, unsigned int index, unsigned int flags)
 {
+
     FT_Face face = 0;
     FT_Byte * buffer = getFace(fontstream, index, face);
     if (face == 0) return (0);
     
-    
+    OpenThreads::ScopedLock<OpenThreads::Mutex> lock(getMutex());
+
     FreeTypeFont3D* font3DImp = new FreeTypeFont3D(buffer,face,flags);
     osgText::Font3D* font3D = new osgText::Font3D(font3DImp);
     

src/osgPlugins/freetype/FreeTypeLibrary.h

@@ -35,6 +35,8 @@ public:
     /** get the singleton instance.*/
     static FreeTypeLibrary* instance();
 
+    OpenThreads::Mutex& getMutex() { return _mutex; }
+
     osgText::Font* getFont(const std::string& fontfile,unsigned int index=0, unsigned int flags=0);
     osgText::Font* getFont(std::istream& fontstream, unsigned int index=0, unsigned int flags=0);
     
@@ -61,9 +63,10 @@ protected:
     typedef std::set< FreeTypeFont* > FontImplementationSet;
     typedef std::set< FreeTypeFont3D* > Font3DImplementationSet;
 
-    FT_Library              _ftlibrary;
-    FontImplementationSet   _fontImplementationSet;
-    Font3DImplementationSet _font3DImplementationSet;
+    mutable OpenThreads::Mutex  _mutex;
+    FT_Library                  _ftlibrary;
+    FontImplementationSet       _fontImplementationSet;
+    Font3DImplementationSet     _font3DImplementationSet;
 
 };