C# BigEndianBinaryReader.Section方法代碼示例

		private static BootstrapMethod[] ReadBootstrapMethods(BigEndianBinaryReader br, ClassFile classFile)
		{
			BigEndianBinaryReader rdr = br.Section(br.ReadUInt32());
			ushort count = rdr.ReadUInt16();
			BootstrapMethod[] bsm = new BootstrapMethod[count];
			for(int i = 0; i < bsm.Length; i++)
			{
				ushort bsm_index = rdr.ReadUInt16();
				if(bsm_index >= classFile.constantpool.Length || !(classFile.constantpool[bsm_index] is ConstantPoolItemMethodHandle))
				{
					throw new ClassFormatError("bootstrap_method_index {0} has bad constant type in class file {1}", bsm_index, classFile.Name);
				}
				classFile.MarkLinkRequiredConstantPoolItem(bsm_index);
				ushort argument_count = rdr.ReadUInt16();
				ushort[] args = new ushort[argument_count];
				for(int j = 0; j < args.Length; j++)
				{
					ushort argument_index = rdr.ReadUInt16();
					if(!classFile.IsValidConstant(argument_index))
					{
						throw new ClassFormatError("argument_index {0} has bad constant type in class file {1}", argument_index, classFile.Name);
					}
					classFile.MarkLinkRequiredConstantPoolItem(argument_index);
					args[j] = argument_index;
				}
				bsm[i] = new BootstrapMethod(bsm_index, args);
			}
			if(!rdr.IsAtEnd)
			{
				throw new ClassFormatError("Bad length on BootstrapMethods in class file {0}", classFile.Name);
			}
			return bsm;
		}

		private static object[] ReadAnnotations(BigEndianBinaryReader br, ClassFile classFile, string[] utf8_cp)
		{
			BigEndianBinaryReader rdr = br.Section(br.ReadUInt32());
			ushort num_annotations = rdr.ReadUInt16();
			object[] annotations = new object[num_annotations];
			for(int i = 0; i < annotations.Length; i++)
			{
				annotations[i] = ReadAnnotation(rdr, classFile, utf8_cp);
			}
			if(!rdr.IsAtEnd)
			{
				throw new ClassFormatError("{0} (RuntimeVisibleAnnotations attribute has wrong length)", classFile.Name);
			}
			return annotations;
		}

				internal void Read(ClassFile classFile, string[] utf8_cp, Method method, BigEndianBinaryReader br, ClassFileParseOptions options)
				{
					max_stack = br.ReadUInt16();
					max_locals = br.ReadUInt16();
					uint code_length = br.ReadUInt32();
					if(code_length > 65535)
					{
						throw new ClassFormatError("{0} (Invalid Code length {1})", classFile.Name, code_length);
					}
					Instruction[] instructions = new Instruction[code_length + 1];
					int basePosition = br.Position;
					int instructionIndex = 0;
					try
					{
						BigEndianBinaryReader rdr = br.Section(code_length);
						while(!rdr.IsAtEnd)
						{
							instructions[instructionIndex].Read((ushort)(rdr.Position - basePosition), rdr, classFile);
							hasJsr |= instructions[instructionIndex].NormalizedOpCode == NormalizedByteCode.__jsr;
							instructionIndex++;
						}
						// we add an additional nop instruction to make it easier for consumers of the code array
						instructions[instructionIndex++].SetTermNop((ushort)(rdr.Position - basePosition));
					}
					catch(ClassFormatError x)
					{
						// any class format errors in the code block are actually verify errors
						verifyError = x.Message;
					}
					this.instructions = new Instruction[instructionIndex];
					Array.Copy(instructions, 0, this.instructions, 0, instructionIndex);
					// build the pcIndexMap
					int[] pcIndexMap = new int[this.instructions[instructionIndex - 1].PC + 1];
					for(int i = 0; i < pcIndexMap.Length; i++)
					{
						pcIndexMap[i] = -1;
					}
					for(int i = 0; i < instructionIndex - 1; i++)
					{
						pcIndexMap[this.instructions[i].PC] = i;
					}
					// convert branch offsets to indexes
					for(int i = 0; i < instructionIndex - 1; i++)
					{
						switch(this.instructions[i].NormalizedOpCode)
						{
							case NormalizedByteCode.__ifeq:
							case NormalizedByteCode.__ifne:
							case NormalizedByteCode.__iflt:
							case NormalizedByteCode.__ifge:
							case NormalizedByteCode.__ifgt:
							case NormalizedByteCode.__ifle:
							case NormalizedByteCode.__if_icmpeq:
							case NormalizedByteCode.__if_icmpne:
							case NormalizedByteCode.__if_icmplt:
							case NormalizedByteCode.__if_icmpge:
							case NormalizedByteCode.__if_icmpgt:
							case NormalizedByteCode.__if_icmple:
							case NormalizedByteCode.__if_acmpeq:
							case NormalizedByteCode.__if_acmpne:
							case NormalizedByteCode.__ifnull:
							case NormalizedByteCode.__ifnonnull:
							case NormalizedByteCode.__goto:
							case NormalizedByteCode.__jsr:
								this.instructions[i].SetTargetIndex(pcIndexMap[this.instructions[i].Arg1 + this.instructions[i].PC]);
								break;
							case NormalizedByteCode.__tableswitch:
							case NormalizedByteCode.__lookupswitch:
								this.instructions[i].MapSwitchTargets(pcIndexMap);
								break;
						}
					}
					// read exception table
					ushort exception_table_length = br.ReadUInt16();
					exception_table = new ExceptionTableEntry[exception_table_length];
					for(int i = 0; i < exception_table_length; i++)
					{
						ushort start_pc = br.ReadUInt16();
						ushort end_pc = br.ReadUInt16();
						ushort handler_pc = br.ReadUInt16();
						ushort catch_type = br.ReadUInt16();
						if(start_pc >= end_pc
							|| end_pc > code_length
							|| handler_pc >= code_length
							|| (catch_type != 0 && !classFile.SafeIsConstantPoolClass(catch_type)))
						{
							throw new ClassFormatError("Illegal exception table: {0}.{1}{2}", classFile.Name, method.Name, method.Signature);
						}
						classFile.MarkLinkRequiredConstantPoolItem(catch_type);
						// if start_pc, end_pc or handler_pc is invalid (i.e. doesn't point to the start of an instruction),
						// the index will be -1 and this will be handled by the verifier
						int startIndex = pcIndexMap[start_pc];
						int endIndex;
						if (end_pc == code_length)
						{
							// it is legal for end_pc to point to just after the last instruction,
							// but since there isn't an entry in our pcIndexMap for that, we have
							// a special case for this
							endIndex = instructionIndex - 1;
						}
//.........這裏部分代碼省略.........

			internal Method(ClassFile classFile, string[] utf8_cp, ClassFileParseOptions options, BigEndianBinaryReader br) : base(classFile, utf8_cp, br)
			{
				// vmspec 4.6 says that all flags, except ACC_STRICT are ignored on <clinit>
				// however, since Java 7 it does need to be marked static
				if(ReferenceEquals(Name, StringConstants.CLINIT) && ReferenceEquals(Signature, StringConstants.SIG_VOID) && (classFile.MajorVersion < 51 || IsStatic))
				{
					access_flags &= Modifiers.Strictfp;
					access_flags |= (Modifiers.Static | Modifiers.Private);
				}
				else
				{
					// LAMESPEC: vmspec 4.6 says that abstract methods can not be strictfp (and this makes sense), but
					// javac (pre 1.5) is broken and marks abstract methods as strictfp (if you put the strictfp on the class)
					if((ReferenceEquals(Name, StringConstants.INIT) && (IsStatic || IsSynchronized || IsFinal || IsAbstract || IsNative))
						|| (IsPrivate && IsPublic) || (IsPrivate && IsProtected) || (IsPublic && IsProtected)
						|| (IsAbstract && (IsFinal || IsNative || IsPrivate || IsStatic || IsSynchronized))
						|| (classFile.IsInterface && (!IsPublic || !IsAbstract)))
					{
						throw new ClassFormatError("{0} (Illegal method modifiers: 0x{1:X})", classFile.Name, access_flags);
					}
				}
				int attributes_count = br.ReadUInt16();
				for(int i = 0; i < attributes_count; i++)
				{
					switch(classFile.GetConstantPoolUtf8String(utf8_cp, br.ReadUInt16()))
					{
						case "Deprecated":
							if(br.ReadUInt32() != 0)
							{
								throw new ClassFormatError("Invalid Deprecated attribute length");
							}
							flags |= FLAG_MASK_DEPRECATED;
							break;
						case "Code":
						{
							if(!code.IsEmpty)
							{
								throw new ClassFormatError("{0} (Duplicate Code attribute)", classFile.Name);
							}
							BigEndianBinaryReader rdr = br.Section(br.ReadUInt32());
							code.Read(classFile, utf8_cp, this, rdr, options);
							if(!rdr.IsAtEnd)
							{
								throw new ClassFormatError("{0} (Code attribute has wrong length)", classFile.Name);
							}
							break;
						}
						case "Exceptions":
						{
							if(exceptions != null)
							{
								throw new ClassFormatError("{0} (Duplicate Exceptions attribute)", classFile.Name);
							}
							BigEndianBinaryReader rdr = br.Section(br.ReadUInt32());
							ushort count = rdr.ReadUInt16();
							exceptions = new string[count];
							for(int j = 0; j < count; j++)
							{
								exceptions[j] = classFile.GetConstantPoolClass(rdr.ReadUInt16());
							}
							if(!rdr.IsAtEnd)
							{
								throw new ClassFormatError("{0} (Exceptions attribute has wrong length)", classFile.Name);
							}
							break;
						}
						case "Signature":
							if(classFile.MajorVersion < 49)
							{
								goto default;
							}
							if(br.ReadUInt32() != 2)
							{
								throw new ClassFormatError("Signature attribute has incorrect length");
							}
							signature = classFile.GetConstantPoolUtf8String(utf8_cp, br.ReadUInt16());
							break;
						case "RuntimeVisibleAnnotations":
							if(classFile.MajorVersion < 49)
							{
								goto default;
							}
							annotations = ReadAnnotations(br, classFile, utf8_cp);
							break;
						case "RuntimeVisibleParameterAnnotations":
						{
							if(classFile.MajorVersion < 49)
							{
								goto default;
							}
							if(low == null)
							{
								low = new LowFreqData();
							}
							BigEndianBinaryReader rdr = br.Section(br.ReadUInt32());
							byte num_parameters = rdr.ReadByte();
							low.parameterAnnotations = new object[num_parameters][];
							for(int j = 0; j < num_parameters; j++)
							{
								ushort num_annotations = rdr.ReadUInt16();
//.........這裏部分代碼省略.........

//.........這裏部分代碼省略.........
				}
			}
			int attributes_count = br.ReadUInt16();
			for (int i = 0; i < attributes_count; i++)
			{
				switch (GetConstantPoolUtf8String(br.ReadUInt16()))
				{
					case "Deprecated":
						deprecated = true;
#if FUZZ_HACK
						br.Skip(br.ReadUInt32());
#else
						if(br.ReadUInt32() != 0)
						{
							throw new ClassFormatError("Deprecated attribute has non-zero length");
						}
#endif
						break;
					case "SourceFile":
						if (br.ReadUInt32() != 2)
						{
							throw new ClassFormatError("SourceFile attribute has incorrect length");
						}
						sourceFile = GetConstantPoolUtf8String(br.ReadUInt16());
						break;
					case "InnerClasses":
#if FUZZ_HACK
						// Sun totally ignores the length of InnerClasses attribute,
						// so when we're running Fuzz this shows up as lots of differences.
						// To get rid off these differences define the FUZZ_HACK symbol.
						BigEndianBinaryReader rdr = br;
						br.ReadUInt32();
#else
						BigEndianBinaryReader rdr = br.Section(br.ReadUInt32());
#endif
						ushort count = rdr.ReadUInt16();
						innerClasses = new InnerClass[count];
						for (int j = 0; j < innerClasses.Length; j++)
						{
							innerClasses[j].innerClass = rdr.ReadUInt16();
							innerClasses[j].outerClass = rdr.ReadUInt16();
							innerClasses[j].name = rdr.ReadUInt16();
							innerClasses[j].accessFlags = (__Modifiers) rdr.ReadUInt16();
							if (innerClasses[j].innerClass != 0 && !(GetConstantPoolItem(innerClasses[j].innerClass) is ConstantPoolItemClass))
							{
								throw new ClassFormatError("{0} (inner_class_info_index has bad constant pool index)", this.Name);
							}
							if (innerClasses[j].outerClass != 0 && !(GetConstantPoolItem(innerClasses[j].outerClass) is ConstantPoolItemClass))
							{
								throw new ClassFormatError("{0} (outer_class_info_index has bad constant pool index)", this.Name);
							}
							if (innerClasses[j].name != 0 && utf8_cp[innerClasses[j].name] == null)
							{
								throw new ClassFormatError("{0} (inner class name has bad constant pool index)", this.Name);
							}
							if (innerClasses[j].innerClass == innerClasses[j].outerClass)
							{
								throw new ClassFormatError("{0} (Class is both inner and outer class)", this.Name);
							}
						}
#if !FUZZ_HACK
						if(!rdr.IsAtEnd)
						{
							throw new ClassFormatError("{0} (InnerClasses attribute has wrong length)", this.Name);
						}
#endif

			internal void Read(ClassFile classFile, Method method, BigEndianBinaryReader br)
			{
				max_stack = br.ReadUInt16();
				max_locals = br.ReadUInt16();
				uint code_length = br.ReadUInt32();
				if (code_length > 65536)
				{
					throw new ClassFormatError("{0} (Invalid Code length {1})", classFile.Name, code_length);
				}
				Instruction[] instructions = new Instruction[code_length + 1];
				int basePosition = br.Position;
				int instructionIndex = 0;
				try
				{
					BigEndianBinaryReader rdr = br.Section(code_length);
					while (!rdr.IsAtEnd)
					{
						instructions[instructionIndex++].Read((ushort) (rdr.Position - basePosition), rdr);
					}
					// we add an additional nop instruction to make it easier for consumers of the code array
					instructions[instructionIndex++].SetTermNop((ushort) (rdr.Position - basePosition));
				}
				catch (ClassFormatError x)
				{
					// any class format errors in the code block are actually verify errors
					verifyError = x.Message;
				}
				this.instructions = new Instruction[instructionIndex];
				Array.Copy(instructions, 0, this.instructions, 0, instructionIndex);
				ushort exception_table_length = br.ReadUInt16();
				exception_table = new ExceptionTableEntry[exception_table_length];
				for (int i = 0; i < exception_table_length; i++)
				{
					exception_table[i] = new ExceptionTableEntry();
					exception_table[i].start_pc = br.ReadUInt16();
					exception_table[i].end_pc = br.ReadUInt16();
					exception_table[i].handler_pc = br.ReadUInt16();
					exception_table[i].catch_type = br.ReadUInt16();
					exception_table[i].ordinal = i;
				}
				ushort attributes_count = br.ReadUInt16();
				for (int i = 0; i < attributes_count; i++)
				{
					switch (classFile.GetConstantPoolUtf8String(br.ReadUInt16()))
					{
						case "LineNumberTable":
							br.Skip(br.ReadUInt32());
							break;
						case "LocalVariableTable":
							br.Skip(br.ReadUInt32());
							break;
						default:
							br.Skip(br.ReadUInt32());
							break;
					}
				}
				// build the pcIndexMap
				pcIndexMap = new int[this.instructions[instructionIndex - 1].PC + 1];
				for (int i = 0; i < pcIndexMap.Length; i++)
				{
					pcIndexMap[i] = -1;
				}
				for (int i = 0; i < instructionIndex - 1; i++)
				{
					pcIndexMap[this.instructions[i].PC] = i;
				}
				// build the argmap
				string sig = method.Signature;
				ArrayList args = new ArrayList();
				int pos = 0;
				if (!method.IsStatic)
				{
					args.Add(pos++);
				}
				for (int i = 1; sig[i] != ')'; i++)
				{
					args.Add(pos++);
					switch (sig[i])
					{
						case 'L':
							i = sig.IndexOf(';', i);
							break;
						case 'D':
						case 'J':
							args.Add(-1);
							break;
						case '[':
							{
								while (sig[i] == '[')
								{
									i++;
								}
								if (sig[i] == 'L')
								{
									i = sig.IndexOf(';', i);
								}
								break;
							}
					}
				}
//.........這裏部分代碼省略.........

		internal Method(ClassFile classFile, BigEndianBinaryReader br) : base(classFile, br)
		{
			// vmspec 4.6 says that all flags, except ACC_STRICT are ignored on <clinit>
			if (Name == "<clinit>" && Signature == "()V")
			{
				access_flags &= __Modifiers.Strictfp;
				access_flags |= (__Modifiers.Static | __Modifiers.Private);
			}
			else
			{
				// LAMESPEC: vmspec 4.6 says that abstract methods can not be strictfp (and this makes sense), but
				// javac (pre 1.5) is broken and marks abstract methods as strictfp (if you put the strictfp on the class)
				if ((Name == "<init>" && (IsStatic || IsSynchronized || IsFinal || IsAbstract || IsNative))
				    || (IsPrivate && IsPublic) || (IsPrivate && IsProtected) || (IsPublic && IsProtected)
				    || (IsAbstract && (IsFinal || IsNative || IsPrivate || IsStatic || IsSynchronized))
				    || (classFile.IsInterface && (!IsPublic || !IsAbstract)))
				{
					throw new ClassFormatError("{0} (Illegal method modifiers: 0x{1:X})", classFile.Name, access_flags);
				}
			}
			int attributes_count = br.ReadUInt16();
			for (int i = 0; i < attributes_count; i++)
			{
				switch (classFile.GetConstantPoolUtf8String(br.ReadUInt16()))
				{
					case "Deprecated":
						deprecated = true;
#if FUZZ_HACK
						br.Skip(br.ReadUInt32());
#else
						if(br.ReadUInt32() != 0)
						{
							throw new ClassFormatError("{0} (Deprecated attribute has non-zero length)", classFile.Name);
						}
#endif
						break;
					case "Code":
						{
							if (!code.IsEmpty)
							{
								throw new ClassFormatError("{0} (Duplicate Code attribute)", classFile.Name);
							}
							BigEndianBinaryReader rdr = br.Section(br.ReadUInt32());
							code.Read(classFile, this, rdr);
							if (!rdr.IsAtEnd)
							{
								throw new ClassFormatError("{0} (Code attribute has wrong length)", classFile.Name);
							}
							break;
						}
					case "Exceptions":
						{
							if (exceptions != null)
							{
								throw new ClassFormatError("{0} (Duplicate Exceptions attribute)", classFile.Name);
							}
							BigEndianBinaryReader rdr = br.Section(br.ReadUInt32());
							ushort count = rdr.ReadUInt16();
							exceptions = new string[count];
							for (int j = 0; j < count; j++)
							{
								exceptions[j] = classFile.GetConstantPoolClass(rdr.ReadUInt16());
							}
							if (!rdr.IsAtEnd)
							{
								throw new ClassFormatError("{0} (Exceptions attribute has wrong length)", classFile.Name);
							}
							break;
						}
					default:
						br.Skip(br.ReadUInt32());
						break;
				}
			}
			if (IsAbstract || IsNative)
			{
				if (!code.IsEmpty)
				{
					throw new ClassFormatError("Abstract or native method cannot have a Code attribute");
				}
			}
			else
			{
				if (code.IsEmpty)
				{
#if FUZZ_HACK
					if (this.Name == "<clinit>")
					{
						code.verifyError = string.Format("Class {0}, method {1} signature {2}: No Code attribute", classFile.Name, this.Name, this.Signature);
						return;
					}
#endif
					throw new ClassFormatError("Method has no Code attribute");
				}
			}
		}