Calculate the name of the cache file for the given source file name and store the calculated file name in the program object.
int scriba_GetCacheFileName(pSbProgram pProgram
)@{
The program returns zero or the error code. It returns SCRIBA_ERROR_FAIL if there
is no cache directory configured.
The code uses a local buffer of length 256 bytes. The full cached file name should fit into this otherwise the program will return SCRIBA_ERROR_BUFFER_SHORT.
The code does not check if there exists an appropriate cache directory or file. It just calculates the file name.