Enum member atomicRcCode

A string that can be mixed-in a class declaration to implement IAtomicRefCounted. dispose is not implemented of course, but is called by release while the object is locked. Classes implementing it are free to do it in a non-thread safe manner as long as dispose does not manipulate external state.

						
				enum atomicRcCode
				 = "\x0a\x0a    import std.typecons : Flag, Yes;\x0a    import std.traits : Unqual;\x0a\x0a    debug {\x0a        ~this() {\x0a            // no gc operation allowed during gc pass\x0a            import std.stdio : stderr;\x0a            enum phrase = rcTypeName ~ \" was not properly disposed\\n\";\x0a            if (refCount != 0) {\x0a                stderr.write(phrase);\x0a                stderr.flush();\x0a            }\x0a        }\x0a        enum rcTypeName = Unqual!(typeof(this)).stringof;\x0a    }\x0a\x0a    debug(rc) {\x0a        private final shared void rcDebug(Args...)(string fmt, Args args)\x0a        {\x0a            import gfx.core.rc : gfxRcLog, rcPrintStack, rcTypeRegex;\x0a            import gfx.core.util : StackTrace;\x0a            import std.algorithm : min;\x0a            import std.regex : matchFirst;\x0a\x0a            if (!matchFirst(rcTypeName, rcTypeRegex)) return;\x0a\x0a            gfxRcLog.debugf(fmt, args);\x0a            if (rcPrintStack) {\x0a                const st = StackTrace.obtain(13, StackTrace.Options.all);\x0a                const frames = st.frames.length > 2 ? st.frames[2 .. $] : [];\x0a                foreach (i, f; frames) {\x0a                    gfxRcLog.debugf(\"  %02d %s\", i, f.symbol);\x0a                }\x0a            }\x0a        }\x0a    }\x0a\x0a\x0a    public final shared override @property size_t refCountShared() const\x0a    {\x0a        import core.atomic : atomicLoad;\x0a        return atomicLoad(_refCount);\x0a    }\x0a\x0a    public final shared override void retainShared()\x0a    {\x0a        import core.atomic : atomicOp;\x0a        const rc = atomicOp!\"+=\"(_refCount, 1);\x0a        debug(rc) {\x0a            rcDebug(\"retain %s: %s -> %s\", rcTypeName, rc-1, rc);\x0a        }\x0a    }\x0a\x0a    public final shared override bool releaseShared(in Flag!\"disposeOnZero\" disposeOnZero = Yes.disposeOnZero)\x0a    {\x0a        import core.atomic : atomicOp;\x0a        const rc = atomicOp!\"-=\"(_refCount, 1);\x0a\x0a        debug(rc) {\x0a            rcDebug(\"release %s: %s -> %s\", rcTypeName, rc+1, rc);\x0a        }\x0a        if (rc == 0 && disposeOnZero) {\x0a            debug(rc) {\x0a                rcDebug(\"dispose %s\", rcTypeName);\x0a            }\x0a            synchronized(this) {\x0a                // cast shared away\x0a                auto obj = cast(Unqual!(typeof(this)))this;\x0a                obj.dispose();\x0a            }\x0a            return true;\x0a        }\x0a        else {\x0a            return false;\x0a        }\x0a    }\x0a\x0a    public final shared override bool rcLockShared()\x0a    {\x0a        import core.atomic : atomicLoad, cas;\x0a        while (1) {\x0a            const c = atomicLoad(_refCount);\x0a\x0a            if (c == 0) {\x0a                debug(rc) {\x0a                    rcDebug(\"rcLock %s: %s\", rcTypeName, c);\x0a                }\x0a                return false;\x0a            }\x0a            if (cas(&_refCount, c, c+1)) {\x0a                debug(rc) {\x0a                    rcDebug(\"rcLock %s: %s\", rcTypeName, c+1);\x0a                }\x0a                return true;\x0a            }\x0a        }\x0a    }\x0a\x0a    private size_t _refCount=0;\x0a";