Patent ID: 6289509
Filing Date: 2001-09-11
Classification: G06F

Abstract:
A method of generating a patch file from an old version of computer code consisting of a series of elements and a new version of computer code consisting of a series of elements where both the old and new versions of computer code are stored in a memory and accessible by a data processor, the method comprising the steps of:establishing an alphabet for processing the old and new versions of computer code where a word consists of one or more elements of the alphabet;sorting the old version of computer code with the data processor alphabetically according to the established alphabet to create a first sorted list of code and maintaining a pointer for each element of the first sorted list of code indicating the element's original location in the old version of computer code;sorting the new version of computer code with the data processor alphabetically according to the established alphabet to create a second sorted list of code and maintaining a pointer for each element of the second sorted list of code indicating the element's original location in the new version of computer code;recursively comparing the first and second sorted lists of code one word at a time for a match of the codes, and storing the match of codes as a sequence of coinciding elements in a coincidences list;upon finding a match of the codes, searching the first and second sorted lists of code again to find the largest sequence of coinciding elements preceding and succeeding the match of codes;storing the largest sequence of coinciding elements in the coincidences list;processing the coincidences list to remove duplicative coincidences; andcreating a patch file from the processed coincidences list.