System and method for applying deltas in a version control system

• US 8,341,132 B2
• Filed: 10/01/2008
• Issued: 12/25/2012
• Est. Priority Date: 10/01/2008
• Status: Active Grant

• Current Assignee: CA, Inc. (d/b/a CA Technologies) (Broadcom, Inc.)
• Original Assignee: CA, Inc. (d/b/a CA Technologies) (Broadcom, Inc.)
• Inventors: DeFrang, Bruce
• Primary Examiner(s): Trujillo, James
• Assistant Examiner(s): Casanova, Jorge A
• Application Number:
  US12/243,263
• Publication Number:
  US 20100082580A1
• Time in Patent Office: 1,546 Days
• Field of Search: 707/625, 707/638, 707/649, 707/695, 715/229
• US Class Current: 707/695
• CPC Class Codes: G06F 40/197 Version control for software G06F8/71
• CPC Class Codes: G06F 8/71 Version control security arrangements therefor G06F21/57; Configuration management

Abstract

A system and method that efficiently maintains multiple versions of a dataset using recursive calls is provided. The method may include fully storing one or more versions of the dataset and storing only changes, called deltas, that occurred from one version to another. Using recursive techniques eliminates the need to generate interim versions in their entirety to generate a requested version. For each position in the requested version the method may include generating content by recursive calls. Each recursive call may initiate a request on an adjacent version to produce content at its corresponding position. The request triggers a recursive call by the adjacent version, which may in turn initiate another request on its adjacent version. This series of recursive calls may be repeated until a fully stored version, which simply returns its content, is reached. The requested version may then generated using content generated for each position by the recursive calls.

Claims

1. A computer-implemented method to retrieve a particular version of a document having a plurality of versions, the method comprising:

receiving a request to generate a particular version of a document from among a plurality of versions of the document, wherein generating the particular version comprises transforming a partial form of the particular version represented by a delta of the particular version into complete contents of the particular version using at least the delta, wherein the delta is stored in a repository, and the delta corresponds to a change to data at a position in the requested particular version of the document relative to an adjacent version of the document;

transforming the partial form into the complete contents of the particular version comprising;

retrieving the delta corresponding to the requested particular version of the document,

recursively determining adjacent data corresponding to the delta at the adjacent version of the document,

applying the delta to the determined adjacent data,

generating data accounting for the change to data at the position based on the applied delta, and

generating the complete contents of the requested particular version of the document based at least in part on the generated data for the delta, wherein the complete contents of the requested particular version of the document is generated without generating the adjacent version of the document in its entirety; and

presenting the requested particular version in response to the received request.

2. The computer-implemented method of claim 1, wherein the adjacent version of the document comprises a second delta, and wherein recursively determining adjacent data comprises:

retrieving the second delta corresponding to the adjacent version of the document, wherein the second delta corresponds to a change to data at a position in the adjacent version of the document relative to a second adjacent version of the document, wherein the second adjacent version of the document is adjacent to the adjacent version of the document;

recursively determining second adjacent data corresponding to the second delta at the second adjacent version of the document;

applying the second delta to the determined second adjacent data;

generating second data based on the applied second delta;

generating the adjacent data based on the generated second data; and

returning the adjacent data.

3. The computer-implemented method of claim 1, wherein the adjacent version of the document is a fully stored version of the document.

4. The computer-implemented method of claim 1, wherein the delta is a forward delta, wherein a fully stored version of the document is a prior version of the document relative to a delta version of the document.

5. The computer-implemented method of claim 1, wherein the delta is a reverse delta, wherein a fully stored version of the document is a subsequent version of the document relative to a delta version of the document.

6. The computer-implemented method of claim 1, wherein the delta is an insert delta.

7. The computer-implemented method of claim 1, wherein the delta is a delete delta.

8. The computer-implemented method of claim 1, wherein the document is text and the position is a line number.

9. The computer-implemented method of claim 1, wherein the document is binary and the position is a byte location.

10. The computer-implemented method of claim 1, further comprising:

tracking a current position while recursively determining adjacent data.

11. The computer-implemented method of claim 10, further comprising:

tracking a current delta being applied.

12. A non-transitory tangible computer readable medium storing computer executable instructions to retrieve a particular version of a document having a plurality of versions, the instructions operable when executed to:

receive a request to generate a particular version of a document from among a plurality of versions of the document, wherein generating the particular version comprises transforming a partial form of the particular version represented by a delta of the particular version into complete contents of the particular version using at least the delta, wherein the delta is stored in a repository, and the delta corresponds to a change to data at a position in the requested particular version of the document relative to an adjacent version of the document;

transform the partial form into the complete contents of the particular version, wherein, to transform, the instructions are further operable when executed to;

retrieve the delta corresponding to the requested particular version of the document,

recursively determine adjacent data corresponding to the delta at the adjacent version of the document,

apply the delta to the determined adjacent data,

generate data accounting for the change to data at the position based on the applied delta, and

generate the complete contents of the requested particular version of the document based at least in part on the generated data for the delta wherein the complete contents of the requested particular version of the document is generated without generating the adjacent version of the document in its entirety; and

present the requested particular version in response to the received request.

13. The non-transitory tangible computer readable medium of claim 12, wherein the adjacent version of the document comprises a second delta, and wherein the instructions to recursively determine adjacent data comprises instructions further operable when executed to:

retrieve the second delta corresponding to the adjacent version of the document, wherein the second delta corresponds to a change to data at a position in the adjacent version of the document relative to a second adjacent version of the document, wherein the second adjacent version of the document is adjacent to the adjacent version of the document;

recursively determine second adjacent data corresponding to the second delta at the second adjacent version of the document;

apply the second delta to the determined second adjacent data;

generate second data based on the applied second delta;

generate the adjacent data based on the generated second data; and

return the adjacent data.

14. The non-transitory tangible computer readable medium of claim 12, wherein the adjacent version of the document is a fully stored version.

15. The non-transitory tangible computer readable medium of claim 12, wherein the delta is a forward delta, wherein a fully stored version of the document is a prior version of the document relative to a delta version of the document.

16. The non-transitory tangible computer readable medium of claim 12, wherein the delta is a reverse delta, wherein a fully stored version of the document is a subsequent version of the ddcument relative to a delta version of the document.

17. The non-transitory tangible computer readable medium of claim 12, wherein the delta is an insert delta.

18. The non-transitory tangible computer readable medium of claim 12, wherein the delta is a delete delta.

19. The non-transitory tangible computer readable medium of claim 12, wherein the document is text and the position is a line number.

20. The non-transitory tangible computer readable medium of claim 12, wherein the document is binary and the position is a byte location.

21. The non-transitory tangible computer readable medium of claim 12, wherein the instructions are further operable when executed to:

track a current position while recursively determining adjacent data.

22. The non-transitory tangible computer readable medium of claim 21, wherein the instructions are further operable when executed to:

track a current delta being applied.

23. A system to retrieve a particular version of a document having a plurality of versions, the system comprising:

a processor configured to;

receive a request to generate a particular version of a document from among a plurality of versions of the document, wherein generating the particular version comprises transforming a partial form of the particular version represented by a delta of the particular version into complete contents of the particular version using the delta, wherein the delta is stored in a repository, and the delta corresponds to a change to data at a position in the requested particular version of the document relative to an adjacent version of the document;

transform the partial form into the complete content of the particular version, wherein, to transform, the processor is further configured to;

retrieve the delta corresponding to the requested particular version of the document,

recursively determine adjacent data corresponding to the delta at the adjacent version of the document,

apply the delta to the determined adjacent data,

generate data accounting for the change to data at the position based on the applied delta, and

generate the complete contents of the requested particular version of the document based at least in part on the generated data for the delta, wherein the complete contents of the requested particular version of the document is generated without generating the adjacent version of the document in its entirety; and

present the requested particular version in response to the received request.

24. The system of claim 23, wherein the adjacent version of the document comprises a second delta, and wherein the processor configured to recursively determine adjacent data is further configured to:

retrieve the second delta corresponding to the adjacent version of the document, wherein the second delta corresponds to a change to data at a position in the adjacent version of the document relative to a second adjacent version of the document, wherein the second adjacent version of the document is adjacent to the adjacent version of the document;

recursively determine second adjacent data corresponding to the second delta at the second adjacent version of the document;

apply the second delta to the determined second adjacent data;

generate second data based on the applied second delta;

generate the adjacent data based on the generated second data; and

return the adjacent data.

25. The system of claim 23, wherein the adjacent version of the document is a fully stored version.

26. The system of claim 23, wherein the delta is a forward delta, wherein a fully stored version of the document is a prior version of the document relative to a delta version of the document.

27. The system of claim 23, wherein the delta is a reverse delta, wherein a fully stored version of the document is a subsequent version of the document relative to a delta version of the document.

28. The system of claim 23, wherein the delta is an insert delta.

29. The system of claim 23, wherein the delta is a delete delta.

30. The system of claim 23, wherein the document is text and the position is a line number.

31. The system of claim 23, wherein the document is binary and the position is a byte location.

32. The system of claim 23, wherein the processor is further configured to:

track a current position while recursively determining adjacent data.

33. The system of claim 32, wherein the processor is further configured to:

track a current delta being applied.