C# IByteReader.SetFileMarker方法代码示例

		//public int getMaxOffset() { return MaxOffset; }



		/**
		 * checks whether the binary file specified by targetFile is compliant
		 * with this byte sequence
		 *
		 * @param targetFile   The binary file to be identified
		 */
		public bool isFileCompliant(IByteReader targetFile)
		{
			//System.out.println("Looking at new byte sequence with reference "+Reference);
			//initialise variables and start with the file marker at the beginning of the file
			bool isCompliant = true;
			bool reverseOrder = (string.Compare(getReference(), "EOFoffset", true) == 0) ? true : false; //(getReference().equalsIgnoreCase("EOFoffset")) ? true : false;
			int ssLoopStart = reverseOrder ? getNumSubSequences() - 1 : 0;
			int ssLoopEnd = reverseOrder ? -1 : getNumSubSequences();
			int searchDirection = reverseOrder ? -1 : 1;
			if (reverseOrder)
			{
				targetFile.SetFileMarker(targetFile.GetNumberOfBytes() - 1L);
			}
			else
			{
				targetFile.SetFileMarker(0L);
			}

			//check whether each subsequence in turn is compliant
			for (int iSS = ssLoopStart; (searchDirection * iSS < searchDirection * ssLoopEnd) & isCompliant; iSS += searchDirection)
			{
				bool isFixedStart = ((string.Compare(getReference(), "EOFoffset", true) == 0) || (string.Compare(getReference(), "BOFoffset", true) == 0)) ? true : false; //getReference().equalsIgnoreCase("EOFoffset") || getReference().equalsIgnoreCase("BOFoffset");
				if ((iSS == ssLoopStart) && (isFixedStart))
				{
					isCompliant = getSubSequence(iSS).isFoundAtStartOfFile(targetFile, reverseOrder, bigEndian); //, MaxOffset);
				}
				else
				{
					isCompliant = getSubSequence(iSS).isFoundAfterFileMarker(targetFile, reverseOrder, bigEndian);
				}
			}
			return isCompliant;
		}

//.........这里部分代码省略.........
				//check the startPosInFile array: remove -2 values, reorder and remove duplicates
				System.Array.Sort(startPosInFile, 0, numOptions);
				int newNumOptions2 = 0;
				long[] newStartPosInFile2 = new long[numOptions];
				if (numOptions > 0)
				{
					if (startPosInFile[0] >= -1L)
					{
						newStartPosInFile2[0] = startPosInFile[0];
						newNumOptions2 = 1;
					}
				}
				for (int i = 1; i < numOptions; i++)
				{
					if (startPosInFile[i] > startPosInFile[i - 1])
					{
						newStartPosInFile2[newNumOptions2] = startPosInFile[i];
						newNumOptions2++;
					}
				}

				if (newNumOptions2 == 0)
				{
					subseqFound = false;
				}
				else
				{
					numOptions = newNumOptions2;
					if (searchDirection < 0)
					{
						//for right to left search direction, reorder in reverse
						for (int iOption = 0; iOption < numOptions; iOption++)
						{
							startPosInFile[iOption] = newStartPosInFile2[numOptions - 1 - iOption];
						}
					}
					else
					{
						//for left to right search direction, copy over as is
						System.Array.Copy(newStartPosInFile2, 0, startPosInFile, 0, numOptions);
					}
				}
			}


			//match remaining sequence fragment
			long newValueStartPosInFile = 0L;
			if (subseqFound)
			{

				long[] newArrayStartPosInFile;
				if (reverseOrder)
				{
					int i = 0;
					subseqFound = false;
					while (i < numOptions && !subseqFound)
					{
						newArrayStartPosInFile = bytePosForLeftFragments(targetFile, 0L, startPosInFile[i], -1, 0, bigEndian);
						if (newArrayStartPosInFile.Length == 0)
						{
							subseqFound = false;
						}
						else
						{
							subseqFound = true;
							newValueStartPosInFile = newArrayStartPosInFile[0] - 1L;  //take away -1???
						}
						i++;
					}
				}
				else
				{
					int i = 0;
					subseqFound = false;
					while (i < numOptions && !subseqFound)
					{
						newArrayStartPosInFile = bytePosForRightFragments(targetFile, startPosInFile[i], targetFile.GetNumberOfBytes() - 1L, 1, 0, bigEndian);
						if (newArrayStartPosInFile.Length == 0)
						{
							subseqFound = false;
						}
						else
						{
							subseqFound = true;
							newValueStartPosInFile = newArrayStartPosInFile[0] + 1L;  //take away +1????
						}
						i++;
					}
				}
			}

			//update the file marker
			if (subseqFound)
			{
				targetFile.SetFileMarker(newValueStartPosInFile);
			}

			return subseqFound;

		}

		/**
		 * Searches for this subsequence after the current file marker position in the file.
		 * Moves the file marker to the end of this subsequence.
		 *
		 * @param targetFile   the binary file to be identified
		 * @param reverseOrder  true if file is being searched from right to left
		 * @param bigEndian    True iff our parent signature is big-endian
		 */
		public bool isFoundAfterFileMarker(IByteReader targetFile, bool reverseOrder, bool bigEndian) {
        
        int searchDirection = reverseOrder?-1:1;
        //get the current file marker
        long startPosInFile = targetFile.GetFileMarker();
        //Add the minimum offset before start of sequence and update the file marker accordingly
        startPosInFile = startPosInFile + (long)(searchDirection * this.getMinSeqOffset());
        if (targetFile.GetNumberOfBytes() < startPosInFile)
        {
            // We're looking for a sequence of bytes at an offset which is longer than the file itself
            return false;
        }
        targetFile.SetFileMarker(startPosInFile);
        //start searching for main sequence after the minimum length of the relevant fragments
        startPosInFile = startPosInFile + (long)(searchDirection * this.getMinFragLength());
        long numFileBytes = reverseOrder?(startPosInFile+1):(targetFile.GetNumberOfBytes() - startPosInFile);
        int numSeqBytes = this.getNumBytes();
        bool subSeqFound = false;
        bool endOfFileReached = false;
        while((!subSeqFound) & (!endOfFileReached)) {
            if((long)numSeqBytes> numFileBytes) {
                endOfFileReached = true;
            } else {
                //compare sequence with file contents directly at fileMarker position
                bool missMatchFound = false;
                int byteLoopStart = reverseOrder?numSeqBytes-1:0;
                int byteLoopEnd   = reverseOrder?0:numSeqBytes-1;
                long tempFileMarker = startPosInFile;
                for(int iByte=byteLoopStart; (!missMatchFound) && (iByte<=numSeqBytes-1) && (iByte>=0); iByte+=searchDirection) {
                    missMatchFound = (byteSequence[iByte] != targetFile.GetByte(tempFileMarker));
                    if(!missMatchFound && showProgress) { System.Console.WriteLine("FLOATING SEQ: A match was found for " + this.getByte(iByte).ToString()); }
                    tempFileMarker+=searchDirection;
                }
                if(!missMatchFound) { //subsequence was found at position fileMarker in the file
                    //Now search for fragments between original fileMarker and startPosInFile
                    if(reverseOrder) {
                        long rightFragEnd;
                        long[] rightFragEndArray = bytePosForRightFragments(targetFile, startPosInFile+1, targetFile.GetFileMarker(), 1, 0, bigEndian);
                        if(rightFragEndArray.Length == 0) {
                            missMatchFound = true;
                        } else {
                            rightFragEnd = rightFragEndArray[0];
                            long leftFragEnd;
                            long[] leftFragEndArray = bytePosForLeftFragments(targetFile, 0, startPosInFile - numSeqBytes, -1, 0, bigEndian);
                            if(leftFragEndArray.Length == 0) {
                                missMatchFound = true;
                            } else {
                                leftFragEnd = leftFragEndArray[0];
                                targetFile.SetFileMarker(leftFragEnd-1L);
                                subSeqFound = true;
                            }
                        }
                        
                    } else {  //search is in forward direction
                        long leftFragEnd;
                        long[] leftFragEndArray = bytePosForLeftFragments(targetFile, targetFile.GetFileMarker(), startPosInFile-1L, -1, 0, bigEndian);
                        if(leftFragEndArray.Length == 0) {
                            missMatchFound = true;
                        } else {
                            leftFragEnd = leftFragEndArray[0];
                            long rightFragEnd;
                            long[] rightFragEndArray = bytePosForRightFragments(targetFile, startPosInFile + numSeqBytes, targetFile.GetNumberOfBytes()-1L, 1, 0, bigEndian);
                            if(rightFragEndArray.Length == 0) {
                                missMatchFound = true;
                            } else {
                                rightFragEnd = rightFragEndArray[0];
                                targetFile.SetFileMarker(rightFragEnd+1L);
                                subSeqFound = true;
                            }
                        }
                    }
                    
                }
                if(missMatchFound) {
                    if (startPosInFile+(long)(searchDirection*numSeqBytes)>=targetFile.GetNumberOfBytes()) {
                        endOfFileReached = true;
                    } else {
                        long numShiftBytes = this.getShift(targetFile.GetByte(startPosInFile+(long)(searchDirection*numSeqBytes))); //reverseOrder?-1:1;   // add shift function for the byte at [fileMarker+(searchDirection*numSeqBytes)] in file
                        numFileBytes -= (numShiftBytes>0)?numShiftBytes:-numShiftBytes;
                        startPosInFile += numShiftBytes;
                        
                        if((startPosInFile<0L) || (startPosInFile>=targetFile.GetNumberOfBytes())) {
                            endOfFileReached = true;
                        }
                    }
                }
            }
        }
        return subSeqFound;
    }