I have the outlined definitions of 2 Plugins, 1 for RSErasurePlugin and 1 for RSFECPlugin. They are published to Cryptography. I am trying to understand how to write primitives to get the work done. Any and All assistance MOST WELCOME! Let's get her done!
I believe I have properly implemented the #declareCVarsIn: and initialized for both plugins.
I am looking at a primitive implementation in RSFECPlugin>>#primitiveInverseWithSize. A few questions: am I grabbing the stack arguments correctly? Testing their values correctly? Correctly calling a method to do the work. Manipulating the stack to setup a return value???
I am doing this...correct?
self pop: 2 thenPushInteger: multiplied. ^interpreterProxy methodReturnInteger: multiplied.
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primitiveInverseWithSize <export: true> <var: 'a' declareC: 'unsigned short' > <var: 'size' declareC: 'unsigned short' >
| a size multiplied | interpreterProxy methodArgumentCount = 2 ifFalse: [ ^interpreterProxy primitiveFailFor: PrimErrBadNumArgs ]. a := interpreterProxy stackIntegerValue: 0. size := interpreterProxy stackIntegerValue: 1.
((interpreterProxy isBytes: a) and: [ (interpreterProxy stSizeOf: a) = 2 ]) ifFalse: [ ^interpreterProxy primitiveFailFor: PrimErrBadArgument ]. ((interpreterProxy isBytes: size) and: [ (interpreterProxy stSizeOf: a) = 2 ]) ifFalse: [ ^interpreterProxy primitiveFailFor: PrimErrBadArgument ]. multiplied := self inverse: a withSize: size. self pop: 2 thenPushInteger: multiplied. ^interpreterProxy methodReturnInteger: multiplied.
And:
inverse: a withSize: size
(a = 0) ifTrue: [RSErasureIllegalArgumentError signal: 'the argument is zero']. ^ expTable at: (size - ((logTable at: (a + 1)) - 1)).
-- --- Kindly, Robert