US6148438A
Expired / Lapsed
US
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System and method for creating composite classes for objects having virtual functions for avoidance of user mode/kernel mode transitions
Assignee: National Instruments Corp
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Filing: 1998-01-06
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Granted: 2000-11-14
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Expires: 2018-01-06
Abstract
Abstract A system and method for creating composite classes for objects having virtual functions, wherein the composite classes enable avoidance of user mode/kernel mode transitions in the operating system. The method first comprises defining the class A, an empty class, and a composite class of the class A and the empty class. These classes are defined in the software program at compile time. The composite class inherits from the composite class and the empty class. The composite class comprises a first mode interface and a second mode interface, wherein the first mode interface and the second mode interface have an opposite ordering of base classes. During execution, the software program instantiates a composite object from the composite class. The method then modifies the composite object to enable the composite object to be shared directly between the first and second modes with reduced mode transitions.
Inventors
- 👤 Geoffrey Schmit
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-02 02:40
CPC Classifications
G; G06; G06F; G06F9/00; G06F9/06; G06F9/46; G06F9/48; G06F9/4806; G06F9/4843; G06F9/44; G06F9/448; G06F9/4488; Y; Y10; Y10S; Y10S707/00; Y10S707/99931; Y10S707/99938
Claims Analysis
Total Claims: 38
Claim 1
Independent Claim
215 words
A method for enabling access to an object in both first and second modes with reduced mode transitions, wherein the object is of a class A, the method comprising: defining the class A, wherein the class A includes one or more virtual functions and a virtual function table pointer, wherein the class A defines a second mode vector table pointer in the first mode; defining an empty class, wherein the empty class includes a virtual function, wherein the empty class includes a virtual function table pointer; defining a composite class of the class A, wherein the composite class inherits from the class A and the empty class; instantiating a composite object from the composite class in one or more of the first mode or the second mode; wherein, if the composite object is instantiated in the second mode, the method comprises: changing the virtual function table pointer for the empty class in the composite object to the first mode virtual function table pointer for class A; wherein, if the composite object is instantiated in the first mode, the method comprises: storing the second mode virtual function table pointer for class A in the second mode vector table pointer; wherein the composite object can be shared directly between first and second modes with reduced mode transitions.
Claim 2
Independent Claim
215 words
A method for enabling access to an object in both first and second modes with reduced mode transitions, wherein the object is of a class A, the method comprising: defining the class A, wherein the class A includes one or more virtual functions and a virtual function table pointer, wherein the class A defines a second mode vector table pointer in the first mode; defining an empty class, wherein the empty class includes a virtual function, wherein the empty class includes a virtual function table pointer; defining a composite class of the class A, wherein the composite class inherits from the class A and the empty class; instantiating a composite object from the composite class in one or more of the first mode or the second mode; wherein, if the composite object is instantiated in the second mode, the method comprises: changing the virtual function table pointer for the empty class in the composite object to the first mode virtual function table pointer for class A; wherein, if the composite object is instantiated in the first mode, the method comprises: storing the second mode virtual function table pointer for class A in the second mode vector table pointer; wherein the composite object can be shared directly between first and second modes with reduced mode transitions.
Claim 3
Dependent Claim
55 words
The method of claim 1, wherein the composite class comprises a first mode interface and a second mode interface, wherein the first mode interface of the composite class comprises a first order of base classes, wherein the second mode interface of the composite class comprises a second ordering of base classes opposite said first order.
Claim 4
Dependent Claim
61 words
The method of claim 1, further comprising: wherein the composite object is instantiated in the first mode, the method further comprising: a second mode process utilizing a virtual function of the composite object after instantiating the composite object in the first mode, wherein the second mode process using the virtual function of the composite object does not require a mode transition.
Claim 5
Dependent Claim
61 words
The method of claim 1, further comprising: wherein the composite object is instantiated in the second mode, the method further comprising: a first mode process utilizing a virtual function of the composite object after instantiating the composite object in the second mode, wherein the first mode process using the virtual function of the composite object does not require a mode transition.
Claim 6
Dependent Claim
48 words
The method of claim 1, wherein said defining the class A, said defining the empty class, and said defining the composite class of the class A are performed during compile time; wherein said instantiating and either of said steps of changing or storing are performed during execution time.
Claim 7
Dependent Claim
24 words
The method of claim 1, wherein the method is performed in a software program, wherein the software program executes under the Windows Operating System.
Claim 8
Dependent Claim
31 words
The method of claim 1, wherein the first mode comprises one of user mode or kernel mode, and wherein the second mode comprises the other of user mode or kernel mode.
Claim 9
Dependent Claim
55 words
The method of claim 7, wherein the composite class comprises a user mode interface and a kernel mode interface, wherein the user mode interface of the composite class comprises a first order of base classes, wherein the kernel mode interface of the composite class comprises a second order of base classes opposite said first order.
Claim 10
Dependent Claim
63 words
The method of claim 7, further comprising: wherein the composite object is instantiated in user mode, the method further comprising: a kernel mode process utilizing a virtual function of the composite object after instantiating the composite object in user mode, wherein the kernel mode process using the virtual function of the composite object does not require a kernel mode to user mode transition.
Claim 11
Dependent Claim
64 words
The method of claim 7, further comprising: wherein the composite object is instantiated in kernel mode, the method further comprising: a user mode process utilizing a virtual function of the composite object after instantiating the composite object in the kernel mode, wherein the user mode process using the virtual function of the composite object does not require a user mode to kernel mode transition.
Claim 12
Dependent Claim
19 words
The method of claim 7, wherein the first mode is user mode and the second mode is kernel mode.
Claim 13
Dependent Claim
19 words
The method of claim 7, wherein the first mode is kernel mode and the second mode is user mode.
Claim 14
Dependent Claim
238 words
A memory media which stores a software program which enables access to an object in both first and second modes with reduced mode transitions, wherein the object is of a class A, wherein the software program comprises program instructions which are executable to perform: defining the class A, wherein the class A includes one or more virtual functions and a virtual function table pointer, where the class A defines a second mode vector table pointer in the first mode; defining an empty class, wherein the empty class includes a virtual function, wherein the empty class includes a virtual function table pointer; defining a composite class of the class A, wherein the composite class inherits from the class A and the empty class; instantiating a composite object from the composite class in one or more of the first mode or the second mode; wherein, if the composite object is instantiated in the second mode, the program instructions are executable to perform: changing the virtual function table pointer for the empty class in the composite object to the first mode virtual function table pointer for class A; wherein, if the composite object is instantiated in the first mode, the program instructions are executable to perform: storing the second mode virtual function table pointer for class A in the second mode vector table pointer; wherein the composite object can be shared directly between first and second modes with reduced mode transitions.
Claim 15
Dependent Claim
238 words
A memory media which stores a software program which enables access to an object in both first and second modes with reduced mode transitions, wherein the object is of a class A, wherein the software program comprises program instructions which are executable to perform: defining the class A, wherein the class A includes one or more virtual functions and a virtual function table pointer, where the class A defines a second mode vector table pointer in the first mode; defining an empty class, wherein the empty class includes a virtual function, wherein the empty class includes a virtual function table pointer; defining a composite class of the class A, wherein the composite class inherits from the class A and the empty class; instantiating a composite object from the composite class in one or more of the first mode or the second mode; wherein, if the composite object is instantiated in the second mode, the program instructions are executable to perform: changing the virtual function table pointer for the empty class in the composite object to the first mode virtual function table pointer for class A; wherein, if the composite object is instantiated in the first mode, the program instructions are executable to perform: storing the second mode virtual function table pointer for class A in the second mode vector table pointer; wherein the composite object can be shared directly between first and second modes with reduced mode transitions.
Claim 16
Dependent Claim
56 words
The memory media of claim 13, wherein the composite class comprises a first mode interface and a second mode interface, wherein the first mode interface of the composite class comprises a first order of base classes, wherein the second mode interface of the composite class comprises a second ordering of base classes opposite said first order.
Claim 17
Dependent Claim
62 words
The memory media of claim 13, wherein the composite object is instantiated in the first mode; wherein a second mode process is operable to utilize a virtual function of the composite object after instantiating the composite object in the first mode, wherein the second mode process is operable to utilize the virtual function of the composite object without requiring a mode transition.
Claim 18
Dependent Claim
61 words
The memory media of claim 13, wherein the composite object is instantiated in the second mode; wherein a first mode process is operable to utilize a virtual function of the composite object after instantiating the composite object in the second mode, wherein the first mode process is operable to utilize the virtual function of the composite without requiring a mode transition.
Claim 19
Dependent Claim
49 words
The memory media of claim 13, wherein said defining the class A, said defining the empty class, and said defining the composite class of the class A are performed during compile time; wherein said instantiating and either of said steps of changing or storing are performed during execution time.
Claim 20
Dependent Claim
32 words
The memory media of claim 13, wherein the first mode comprises one of user mode or kernel mode, and wherein the second mode comprises the other of user mode or kernel mode.
Claim 21
Independent Claim
216 words
A method for enabling access to an object in both user and kernel modes with reduced user mode/kernel mode transitions, wherein the object is of a class A, the method comprising: defining the class A, wherein the class A includes one or more virtual functions and a virtual function table pointer, wherein the class A defines a kernel mode vector table pointer in user mode; defining an empty class, wherein the empty class includes a virtual function, wherein the empty class includes a virtual function table pointer; defining a composite class of the class A, wherein the composite class inherits from the class A and the empty class; instantiating a composite object from the composite class in one or more of the user mode or the kernel mode; wherein, if the composite object is instantiated in kernel mode, the method comprises: changing the virtual function table pointer for the empty class in the composite object to the user mode virtual function table pointer for class A; wherein, if the composite object is instantiated in user mode, the method comprises: storing the kernel mode virtual function table pointer for class A in the kernel mode vector table pointer; wherein the composite object can be shared directly between user and kernel modes with reduced user mode/kernel mode transitions.
Claim 22
Independent Claim
216 words
A method for enabling access to an object in both user and kernel modes with reduced user mode/kernel mode transitions, wherein the object is of a class A, the method comprising: defining the class A, wherein the class A includes one or more virtual functions and a virtual function table pointer, wherein the class A defines a kernel mode vector table pointer in user mode; defining an empty class, wherein the empty class includes a virtual function, wherein the empty class includes a virtual function table pointer; defining a composite class of the class A, wherein the composite class inherits from the class A and the empty class; instantiating a composite object from the composite class in one or more of the user mode or the kernel mode; wherein, if the composite object is instantiated in kernel mode, the method comprises: changing the virtual function table pointer for the empty class in the composite object to the user mode virtual function table pointer for class A; wherein, if the composite object is instantiated in user mode, the method comprises: storing the kernel mode virtual function table pointer for class A in the kernel mode vector table pointer; wherein the composite object can be shared directly between user and kernel modes with reduced user mode/kernel mode transitions.
Claim 23
Dependent Claim
55 words
The method of claim 19, wherein the composite class comprises a user mode interface and a kernel mode interface, wherein the user mode interface of the composite class comprises a first order of base classes, wherein the kernel mode interface of the composite class comprises a second ordering of base classes opposite said first order.
Claim 24
Dependent Claim
63 words
The method of claim 19, further comprising: wherein the composite object is instantiated in user mode, the method further comprising: a kernel mode process utilizing a virtual function of the composite object after instantiating the composite object in user mode, wherein the kernel mode process using the virtual function of the composite object does not require a kernel mode to user mode transition.
Claim 25
Dependent Claim
59 words
The method of claim 19, further comprising: wherein the composite object is instantiated in kernel mode, the method further comprising: a user mode process utilizing a virtual function of the composite object after instantiating the composite object in kernel mode, wherein the user mode process using the virtual function of the composite object does not require a mode transition.
Claim 26
Independent Claim
216 words
A method for enabling access to an object in both user and kernel modes with reduced user mode/kernel mode transitions, wherein the object is of a class A, the method comprising: defining the class A, wherein the class A includes one or more virtual functions and a virtual function table pointer, wherein the class A defines a user mode vector table pointer in kernel mode; defining an empty class, wherein the empty class includes a virtual function, wherein the empty class includes a virtual function table pointer; defining a composite class of the class A, wherein the composite class inherits from the class A and the empty class; instantiating a composite object from the composite class in one or more of the user mode or the kernel mode; wherein, if the composite object is instantiated in user mode, the method comprises: changing the virtual function table pointer for the empty class in the composite object to the kernel mode virtual function table pointer for class A; wherein, if the composite object is instantiated in kernel mode, the method comprises: storing the user mode virtual function table pointer for class A in the user mode vector table pointer; wherein the composite object can be shared directly between user and kernel modes with reduced user mode/kernel mode transitions.
Claim 27
Independent Claim
216 words
A method for enabling access to an object in both user and kernel modes with reduced user mode/kernel mode transitions, wherein the object is of a class A, the method comprising: defining the class A, wherein the class A includes one or more virtual functions and a virtual function table pointer, wherein the class A defines a user mode vector table pointer in kernel mode; defining an empty class, wherein the empty class includes a virtual function, wherein the empty class includes a virtual function table pointer; defining a composite class of the class A, wherein the composite class inherits from the class A and the empty class; instantiating a composite object from the composite class in one or more of the user mode or the kernel mode; wherein, if the composite object is instantiated in user mode, the method comprises: changing the virtual function table pointer for the empty class in the composite object to the kernel mode virtual function table pointer for class A; wherein, if the composite object is instantiated in kernel mode, the method comprises: storing the user mode virtual function table pointer for class A in the user mode vector table pointer; wherein the composite object can be shared directly between user and kernel modes with reduced user mode/kernel mode transitions.
Claim 28
Dependent Claim
55 words
The method of claim 23, wherein the composite class comprises a user mode interface and a kernel mode interface, wherein the user mode interface of the composite class comprises a first order of base classes, wherein the kernel mode interface of the composite class comprises a second ordering of base classes opposite said first order.
Claim 29
Dependent Claim
63 words
The method of claim 23, further comprising: wherein the composite object is instantiated in user mode, the method further comprising: a kernel mode process utilizing a virtual function of the composite object after instantiating the composite object in user mode, wherein the kernel mode process using the virtual function of the composite object does not require a kernel mode to user mode transition.
Claim 30
Dependent Claim
59 words
The method of claim 23, further comprising: wherein the composite object is instantiated in kernel mode, the method further comprising: a user mode process utilizing a virtual function of the composite object after instantiating the composite object in kernel mode, wherein the user mode process using the virtual function of the composite object does not require a mode transition.
Claim 31
Independent Claim
155 words
A method for enabling access to an object in both first and second modes with reduced mode transitions, wherein the object is of a class A, the method comprising: defining the class A, wherein the class A includes one or more virtual functions and a virtual function table pointer, wherein the class A defines a second mode vector table pointer in the first mode; defining an empty class, wherein the empty class includes a virtual function, wherein the empty class includes a virtual function table pointer; defining a composite class of the class A, wherein the composite class inherits from the class A and the empty class; instantiating a composite object from the composite class in one or more of the first mode or the second mode; modifying the composite object to create a modified composite object, wherein said modified composite object can be shared directly between first and second modes with reduced mode transitions.
Claim 32
Independent Claim
155 words
A method for enabling access to an object in both first and second modes with reduced mode transitions, wherein the object is of a class A, the method comprising: defining the class A, wherein the class A includes one or more virtual functions and a virtual function table pointer, wherein the class A defines a second mode vector table pointer in the first mode; defining an empty class, wherein the empty class includes a virtual function, wherein the empty class includes a virtual function table pointer; defining a composite class of the class A, wherein the composite class inherits from the class A and the empty class; instantiating a composite object from the composite class in one or more of the first mode or the second mode; modifying the composite object to create a modified composite object, wherein said modified composite object can be shared directly between first and second modes with reduced mode transitions.
Claim 33
Dependent Claim
93 words
The method of claim 27, wherein, if the composite object is instantiated in the second mode, said modifying comprises: changing the virtual function table pointer for the empty class in the composite object to the first mode virtual function table pointer for class A; wherein, if the composite object is instantiated in the first mode, said modifying comprises: storing the second mode virtual function table pointer for class A in the second mode vector table pointer; wherein the composite object can be shared directly between first and second modes with reduced mode transitions.
Claim 34
Dependent Claim
55 words
The method of claim 27, wherein the composite class comprises a first mode interface and a second mode interface, wherein the first mode interface of the composite class comprises a first order of base classes wherein the second mode interface of the composite class comprises a second ordering of base classes opposite said first order.
Claim 35
Dependent Claim
53 words
The method of claim 27, wherein the composite object is instantiated in the first mode, the method further comprising: a second mode process utilizing a virtual function of the composite object after said modifying, wherein the second mode process using the virtual function of the composite object does not require a mode transition.
Claim 36
Dependent Claim
53 words
The method of claim 27, wherein the composite object is instantiated in the second mode, the method further comprising: a first mode process utilizing a virtual function of the composite object after said modifying, wherein the first mode process using the virtual function of the composite object does not require a mode transition.
Claim 37
Dependent Claim
48 words
The method of claim 27, wherein said defining the class A, said defining the empty class, and said defining the composite class of the class A are performed during compile time; wherein said instantiating and either of said steps of changing or storing are performed during execution time.
Claim 38
Dependent Claim
31 words
The method of claim 27, wherein the first mode comprises one of user mode or kernel mode, and wherein the second mode comprises the other of user mode or kernel mode.
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USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 2003-11-14 | 2004-05-15 | 2004-11-14 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 2007-11-14 | 2008-05-15 | 2008-11-14 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2011-11-14 | 2012-05-15 | 2012-11-14 | $7700.00 | Window Closed / Lapsed |