comparison Source/Aspects/Builders/InterceptorAspectBuilder.cs @ 0:f990fcb411a9

Копия текущей версии из github
author cin
date Thu, 27 Mar 2014 21:46:09 +0400
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-1:000000000000 0:f990fcb411a9
1 using System;
2 using System.Reflection;
3 using System.Reflection.Emit;
4
5 namespace BLToolkit.Aspects.Builders
6 {
7 using Reflection;
8 using TypeBuilder.Builders;
9
10 public class InterceptorAspectBuilder : AbstractTypeBuilderBase
11 {
12 public InterceptorAspectBuilder(
13 Type interceptorType, InterceptType interceptType, string configString, int priority, bool localInterceptor)
14 {
15 _interceptorType = interceptorType;
16 _interceptType = interceptType;
17 _configString = configString;
18 _priority = priority;
19 _localInterceptor = localInterceptor;
20 }
21
22 private readonly Type _interceptorType;
23 private readonly InterceptType _interceptType;
24 private readonly string _configString;
25 private readonly int _priority;
26 private readonly bool _localInterceptor;
27
28 private FieldBuilder _interceptorField;
29 private LocalBuilder _infoField;
30
31 public override int GetPriority(BuildContext context)
32 {
33 return _priority;
34 }
35
36 public override bool IsApplied(BuildContext context, AbstractTypeBuilderList builders)
37 {
38 if (_interceptorType == null && _interceptType == 0)
39 return false;
40
41 foreach (var builder in builders)
42 {
43 var interceptor = builder as InterceptorAspectBuilder;
44
45 if (interceptor != null)
46 {
47 if (interceptor._interceptorType == null && interceptor._interceptType == 0)
48 return false;
49
50 if (builder == this)
51 break;
52 }
53 }
54
55 if (context.IsMethodOrProperty) switch (context.Step)
56 {
57 case BuildStep.Begin: return true;
58 case BuildStep.Before: return (_interceptType & InterceptType.BeforeCall) != 0;
59 case BuildStep.After: return (_interceptType & InterceptType.AfterCall) != 0;
60 case BuildStep.Catch: return (_interceptType & InterceptType.OnCatch) != 0;
61 case BuildStep.Finally: return (_interceptType & InterceptType.OnFinally) != 0;
62 case BuildStep.End: return true;
63 }
64
65 return false;
66 }
67
68 public override bool IsCompatible(BuildContext context, IAbstractTypeBuilder typeBuilder)
69 {
70 var builder = typeBuilder as InterceptorAspectBuilder;
71
72 return builder == null || _interceptorType != builder._interceptorType;
73 }
74
75 public override void Build(BuildContext context)
76 {
77 if (context.Step == BuildStep.Begin || context.Step == BuildStep.End)
78 {
79 base.Build(context);
80 return;
81 }
82
83 Context = context;
84
85 var emit = Context.MethodBuilder.Emitter;
86
87 // Push ref & out parameters.
88 //
89 var parameters = Context.CurrentMethod.GetParameters();
90
91 for (var i = 0; i < parameters.Length; i++)
92 {
93 var p = parameters[i];
94
95 if (!p.ParameterType.IsByRef)
96 continue;
97
98 emit
99 .ldloc (_infoField)
100 .callvirt (typeof(InterceptCallInfo).GetProperty("ParameterValues").GetGetMethod())
101 .ldc_i4 (i)
102 .ldargEx (p, true)
103 .stelem_ref
104 .end()
105 ;
106 }
107
108 // Push return value.
109 //
110 if (Context.ReturnValue != null)
111 {
112 emit
113 .ldloc (_infoField)
114 .ldloc (Context.ReturnValue)
115 .boxIfValueType (Context.CurrentMethod.ReturnType)
116 .callvirt (typeof(InterceptCallInfo).GetProperty("ReturnValue").GetSetMethod())
117 ;
118 }
119
120 // Set Exception.
121 //
122 if (Context.Step == BuildStep.Catch)
123 {
124 emit
125 .ldloc(_infoField)
126 .ldloc(Context.Exception)
127 .callvirt(typeof(InterceptCallInfo).GetProperty("Exception").GetSetMethod())
128 ;
129 }
130
131 // Set intercept result.
132 //
133 emit
134 .ldloc (_infoField)
135 .ldc_i4 ((int)InterceptResult.Continue)
136 .callvirt (typeof(InterceptCallInfo).GetProperty("InterceptResult").GetSetMethod())
137 ;
138
139 // Set intercept type.
140 //
141 InterceptType interceptType;
142
143 switch (Context.Step)
144 {
145 case BuildStep.Before: interceptType = InterceptType.BeforeCall; break;
146 case BuildStep.After: interceptType = InterceptType.AfterCall; break;
147 case BuildStep.Catch: interceptType = InterceptType.OnCatch; break;
148 case BuildStep.Finally: interceptType = InterceptType.OnFinally; break;
149 default:
150 throw new InvalidOperationException();
151 }
152
153 emit
154 .ldloc (_infoField)
155 .ldc_i4 ((int)interceptType)
156 .callvirt (typeof(InterceptCallInfo).GetProperty("InterceptType").GetSetMethod())
157
158 // Call interceptor.
159 //
160 .LoadField(_interceptorField)
161 .ldloc (_infoField)
162 .callvirt (typeof(IInterceptor), "Intercept", typeof(InterceptCallInfo))
163 ;
164
165 // Pop return value.
166 //
167 if (Context.ReturnValue != null)
168 {
169 emit
170 .ldloc (_infoField)
171 .callvirt (typeof(InterceptCallInfo).GetProperty("ReturnValue").GetGetMethod())
172 .CastFromObject (Context.CurrentMethod.ReturnType)
173 .stloc (Context.ReturnValue)
174 ;
175 }
176
177 // Pop ref & out parameters.
178 //
179 for (var i = 0; i < parameters.Length; i++)
180 {
181 var p = parameters[i];
182
183 if (!p.ParameterType.IsByRef)
184 continue;
185
186 var type = p.ParameterType.GetElementType();
187
188 emit
189 .ldarg (p)
190 .ldloc (_infoField)
191 .callvirt (typeof(InterceptCallInfo).GetProperty("ParameterValues").GetGetMethod())
192 .ldc_i4 (i)
193 .ldelem_ref
194 .CastFromObject (type)
195 .stind (type)
196 ;
197 }
198
199 // Check InterceptResult
200 emit
201 .ldloc (_infoField)
202 .callvirt (typeof(InterceptCallInfo).GetProperty("InterceptResult").GetGetMethod())
203 .ldc_i4 ((int)InterceptResult.Return)
204 .beq (Context.ReturnLabel)
205 ;
206 }
207
208 private static int _methodCounter;
209
210 private LocalBuilder GetInfoField()
211 {
212 var field = Context.GetItem<LocalBuilder>("$BLToolkit.InfoField");
213
214 if (field == null)
215 {
216 _methodCounter++;
217
218 // Create MethodInfo field.
219 //
220 var methodInfo = Context.CreatePrivateStaticField(
221 "_methodInfo$" + Context.CurrentMethod.Name + _methodCounter, typeof(CallMethodInfo));
222
223 var emit = Context.MethodBuilder.Emitter;
224
225 var checkMethodInfo = emit.DefineLabel();
226
227 emit
228 .LoadField (methodInfo)
229 .brtrue_s (checkMethodInfo)
230 .call (typeof(MethodBase), "GetCurrentMethod")
231 .castclass (typeof(MethodInfo))
232 .newobj (TypeHelper.GetConstructor(typeof(CallMethodInfo), typeof(MethodInfo)))
233 .stsfld (methodInfo)
234 .MarkLabel (checkMethodInfo)
235 ;
236
237 // Create & initialize the field.
238 //
239 field = emit.DeclareLocal(typeof(InterceptCallInfo));
240
241 emit
242 .newobj (TypeHelper.GetDefaultConstructor(typeof(InterceptCallInfo)))
243 .dup
244 .ldarg_0
245 .callvirt (typeof(InterceptCallInfo).GetProperty("Object").GetSetMethod())
246
247 .dup
248 .LoadField(methodInfo)
249 .callvirt (typeof(InterceptCallInfo).GetProperty("CallMethodInfo").GetSetMethod())
250 ;
251
252 var parameters = Context.CurrentMethod.GetParameters();
253
254 for (var i = 0; i < parameters.Length; i++)
255 {
256 var p = parameters[i];
257
258 if (p.ParameterType.IsByRef)
259 continue;
260
261 emit
262 .dup
263 .callvirt (typeof(InterceptCallInfo).GetProperty("ParameterValues").GetGetMethod())
264 .ldc_i4 (i)
265 .ldargEx (p, true)
266 .stelem_ref
267 .end()
268 ;
269 }
270
271 emit.stloc(field);
272
273 Context.Items.Add("$BLToolkit.MethodInfo", methodInfo);
274 Context.Items.Add("$BLToolkit.InfoField", field);
275 }
276
277 return field;
278 }
279
280 private FieldBuilder GetInterceptorField()
281 {
282 var fieldName = "_interceptor$" + _interceptorType.FullName + "$_" + Context.CurrentMethod.Name + _methodCounter;
283 var field = Context.GetField(fieldName);
284
285 if (field == null)
286 {
287 // Create MethodInfo field.
288 //
289 field = _localInterceptor?
290 Context.CreatePrivateField (fieldName, typeof(IInterceptor)):
291 Context.CreatePrivateStaticField(fieldName, typeof(IInterceptor));
292
293 var emit = Context.MethodBuilder.Emitter;
294
295 var checkInterceptor = emit.DefineLabel();
296 var methodInfo = Context.GetItem<FieldBuilder>("$BLToolkit.MethodInfo");
297
298 emit
299 .LoadField (field)
300 .brtrue_s (checkInterceptor)
301 ;
302
303 if (!field.IsStatic)
304 emit.ldarg_0.end();
305
306 emit
307 .newobj (TypeHelper.GetDefaultConstructor(_interceptorType))
308 .castclass (typeof(IInterceptor))
309 ;
310
311 if (field.IsStatic)
312 emit.stsfld(field);
313 else
314 emit.stfld(field);
315
316 emit
317 .LoadField (field)
318 .LoadField (methodInfo)
319 .ldstrEx (_configString ?? "")
320 .callvirt (typeof(IInterceptor), "Init", typeof(CallMethodInfo), typeof(string))
321
322 .MarkLabel (checkInterceptor)
323 ;
324 }
325
326 return field;
327 }
328
329 protected override void BeginMethodBuild()
330 {
331 _infoField = GetInfoField();
332 _interceptorField = GetInterceptorField();
333 }
334
335 protected override void EndMethodBuild()
336 {
337 Context.Items.Remove("$BLToolkit.MethodInfo");
338 Context.Items.Remove("$BLToolkit.InfoField");
339 }
340 }
341 }