Abstract: A pair of functions setjmp( ) and longjmp( ) shares the data related to the program context. When instrumentation starts, the instrumentation tool creates the instrumented code, resulting in two sets of program code, e.g., the original code and the instrumented code. Functions setjmp( ) and longjmp( ) in the instrumented code may be referred to as functions setjmp′( ) and longjmp′( ), respectively. In one embodiment, when function setjmp′( ) is reached, but before being executed, the setjmp′-continued location is identified, and based on this setjmp′-continued location, the corresponding setjmp-continued location is also identified and saved for later use. When un-instrumentation occurs, the instrumented code is discarded, execution reverts to the original code, and function longjmp( ) is executed, which, based on the saved information, causes execution to continue at the setjmp-continued location.

Abstract: An anti-piracy system for remotely served computer applications provides a client network filesystem that performs several techniques to prevent the piracy of application programs. The invention provides client-side fine-grained filtering of file accesses directed at remotely served files. Another technique filters file accesses based on where the code for the process that originated the request is stored. Yet another technique Identifies crucial portions of remotely served files and filters file accesses depending on the portion targeted. A further technique filters file accesses based on the surmised purpose of the file access as determined by examining the program stack or flags associated with the request. A final technique filters file accesses based on the surmised purpose of the file access as determined by examining a history of previous file accesses by the same process.