// Constructor.
internal BaseVsaEngine(String language, String version, bool supportDebug)
{
applicationPath = String.Empty;
assemblyVersion = version;
compiledRootNamespace = null;
engineMoniker = String.Empty;
engineName = String.Empty;
engineSite = null;
errorLocale = CultureInfo.CurrentCulture.LCID;
executionEvidence = null;
failedCompilation = false;
genDebugInfo = false;
haveCompiledState = false;
isClosed = false;
isDebugInfoSupported = supportDebug;
isEngineCompiled = false;
isEngineDirty = false;
isEngineInitialized = false;
isEngineRunning = false;
loadedAssembly = null;
rootNamespace = String.Empty;
scriptLanguage = language;
startupClass = null;
startupInstance = null;
vsaItems = null;
}
// Constructor.
internal BaseVsaEngine(String language, String version, bool supportDebug)
{
applicationPath = String.Empty;
assemblyVersion = version;
compiledRootNamespace = null;
engineMoniker = String.Empty;
engineName = String.Empty;
engineSite = null;
errorLocale = CultureInfo.CurrentCulture.LCID;
executionEvidence = null;
failedCompilation = false;
genDebugInfo = false;
haveCompiledState = false;
isClosed = false;
isDebugInfoSupported = supportDebug;
isEngineCompiled = false;
isEngineDirty = false;
isEngineInitialized = false;
isEngineRunning = false;
loadedAssembly = null;
rootNamespace = String.Empty;
scriptLanguage = language;
startupClass = null;
startupInstance = null;
vsaItems = null;
}
public virtual void Run(){
this.TryObtainLock();
try{
Preconditions(Pre.EngineNotClosed |
Pre.EngineNotRunning |
Pre.RootMonikerSet |
Pre.SiteSet |
Pre.RootNamespaceSet);
// managed engines cannot support the AppDomain property so we always use the current one
AppDomain appDomain = System.AppDomain.CurrentDomain;
if (this.haveCompiledState){
// make sure the RootNamespace hasn't been changed since the compilation
if (this.rootNamespace != this.compiledRootNamespace)
throw new VsaException(VsaError.RootNamespaceInvalid);
this.loadedAssembly = this.LoadCompiledState();
appDomain.SetData(this.engineMoniker, this.loadedAssembly);
}else{
// if Compile returned false last time it was called, quit before cache lookup or callback
if (this.failedCompilation)
throw new VsaException(VsaError.EngineNotCompiled);
this.startupClass = null;
this.loadedAssembly = appDomain.GetData(this.engineMoniker) as Assembly;
if (this.loadedAssembly == null){
// assembly is not in the cache, so callback to the site for compiled state
// prevent multiple callbacks which could result in duplicate assemblies being loaded into the AppDomain
string mutexName = this.engineMoniker + "/" + appDomain.GetHashCode().ToString(CultureInfo.InvariantCulture);
Mutex compiledStateCallbackMutex = new Mutex(false, mutexName);
if (compiledStateCallbackMutex.WaitOne()){
try{
// see if there was another callback before we got the lock
this.loadedAssembly = appDomain.GetData(this.engineMoniker) as Assembly;
if (this.loadedAssembly == null){
byte[] pe;
byte[] pdb;
this.engineSite.GetCompiledState(out pe, out pdb);
if (pe == null)
throw new VsaException(VsaError.GetCompiledStateFailed);
this.loadedAssembly = Assembly.Load(pe, pdb, this.executionEvidence);
appDomain.SetData(this.engineMoniker, this.loadedAssembly);
}
}finally{
compiledStateCallbackMutex.ReleaseMutex();
compiledStateCallbackMutex.Close();
}
}
}
}
// update the _Startup class Type object (if needed)
try{
if (this.startupClass == null)
this.startupClass = this.loadedAssembly.GetType(this.rootNamespace + "._Startup", true);
}catch(Exception e){
// the _Startup class was not in the RootNamespace
throw new VsaException(VsaError.BadAssembly, e.ToString(), e);
}
// set the engine to running, callback for global and event instances, then run global code
try{
this.startupInstance = (BaseVsaStartup)Activator.CreateInstance(this.startupClass);
this.isEngineRunning = true;
this.startupInstance.SetSite(this.engineSite);
this.startupInstance.Startup();
}catch(Exception e){
throw new VsaException(VsaError.UnknownError, e.ToString(), e);
}
}finally{
this.ReleaseLock();
}
}
public virtual void Run()
{
this.TryObtainLock();
try{
Preconditions(Pre.EngineNotClosed |
Pre.EngineNotRunning |
Pre.RootMonikerSet |
Pre.SiteSet |
Pre.RootNamespaceSet);
// managed engines cannot support the AppDomain property so we always use the current one
AppDomain appDomain = System.AppDomain.CurrentDomain;
if (this.haveCompiledState)
{
// make sure the RootNamespace hasn't been changed since the compilation
if (this.rootNamespace != this.compiledRootNamespace)
{
throw new VsaException(VsaError.RootNamespaceInvalid);
}
this.loadedAssembly = this.LoadCompiledState();
appDomain.SetData(this.engineMoniker, this.loadedAssembly);
}
else
{
// if Compile returned false last time it was called, quit before cache lookup or callback
if (this.failedCompilation)
{
throw new VsaException(VsaError.EngineNotCompiled);
}
this.startupClass = null;
this.loadedAssembly = appDomain.GetData(this.engineMoniker) as Assembly;
if (this.loadedAssembly == null)
{
// assembly is not in the cache, so callback to the site for compiled state
// prevent multiple callbacks which could result in duplicate assemblies being loaded into the AppDomain
string mutexName = this.engineMoniker + "/" + appDomain.GetHashCode().ToString(CultureInfo.InvariantCulture);
Mutex compiledStateCallbackMutex = new Mutex(false, mutexName);
if (compiledStateCallbackMutex.WaitOne())
{
try{
// see if there was another callback before we got the lock
this.loadedAssembly = appDomain.GetData(this.engineMoniker) as Assembly;
if (this.loadedAssembly == null)
{
byte[] pe;
byte[] pdb;
this.engineSite.GetCompiledState(out pe, out pdb);
if (pe == null)
{
throw new VsaException(VsaError.GetCompiledStateFailed);
}
this.loadedAssembly = Assembly.Load(pe, pdb, this.executionEvidence);
appDomain.SetData(this.engineMoniker, this.loadedAssembly);
}
}finally{
compiledStateCallbackMutex.ReleaseMutex();
compiledStateCallbackMutex.Close();
}
}
}
}
// update the _Startup class Type object (if needed)
try{
if (this.startupClass == null)
{
this.startupClass = this.loadedAssembly.GetType(this.rootNamespace + "._Startup", true);
}
}catch (Exception e) {
// the _Startup class was not in the RootNamespace
throw new VsaException(VsaError.BadAssembly, e.ToString(), e);
}
// set the engine to running, callback for global and event instances, then run global code
try{
this.startupInstance = (BaseVsaStartup)Activator.CreateInstance(this.startupClass);
this.isEngineRunning = true;
this.startupInstance.SetSite(this.engineSite);
this.startupInstance.Startup();
}catch (Exception e) {
throw new VsaException(VsaError.UnknownError, e.ToString(), e);
}
}finally{
this.ReleaseLock();
}
}