System and method for runtime detection of program parameters
View Patent ↗The present invention provides a computer program utility that may be employed in a COBOL programming environment to calculate the number of parameters passed from one program to another. The parameter counting utility may be called from a second program upon receiving a call with parameters from a first program. The parameter counting utility derives the number of parameters by examining the save area of a first program in relation to the save area of the second program which placed the call to the parameter counting utility. The parameter counting utility may then return the number of parameters to the calling program in the form of a variable.
1. A method for determining a number of parameters in a linkage section in a call that has been passed to a called program from a calling program, said method comprising:
examining a calling program save area until a first save area is found;
locating, in said save area, a parameter list from a register, the parameter list including at least one address;
identifying a first address in the parameter list;
searching a first bit of each address in the parameter list until the first bit equals one, wherein the address with the first bit set to one is the last address;
counting a number of addresses in the parameter list from the first address to the last address to obtain a total number of addresses; and
transmitting the total number of addresses back to the called program as a variable.
2. The method of claim 1 , wherein the called program includes a COBOL program.
3. The method of claim 1 , wherein the method is executed by an assembler program.
4. The method of claim 1 , wherein the first save area includes a plurality of registers.
5. The method of claim 1 , wherein the examining of the calling program includes finding the first save area by traversing the calling program save area until the first save area is found.
6. The method of claim 1 , wherein the parameter list includes at least one address corresponding to a parameter.