2004 Reports

Determining Interfaces Using Type Inference

Li, Chun; Edwards, Stephen A.

Porting software usually requires understanding what library functions the program being ported uses since this functionality must be either found or reproduced in the ported program's new environment. This is usually done manually through code inspections. We propose a type inference algorithm able to infer basic information about the library functions a particular C program uses in the absence of declaration information for the library (e.g., without header files). Based on a simple but efficient inference algorithm, we were able to infer declarations for much of the PalmOS API from the source of a twenty-seven-thousand-line C program. Such a tool will aid in the problem of program understanding when porting programs, especially from poorly-documented or lost legacy environments.