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2.4.6 Per Function Execution Contexts

Function specific data sets may be indicated to be supplied to the methods implementing the function logics, together with the general execution context.

If accessing a specific data context is desired, the function definition must include the X1f4_E4_TEXT_LINK bit in its flags field.

See Function Flags.

Whenever the expression parser picks up a reference to a function requiring a specific execution context it calls the function_set.fix method of the struct x1f4_attributes_type expression parsing context, immediately after the function_set.get call that looked up the function. The function_set.fix method is supplied the function lookup context as first argument (the function_set.context field in the parsing context) and the function definition as the second (as retrieved via the immediately preceding function_set.get call). The function_set.fix method is expected to set the context reference (void pointer, that is) for which a reference is passed as the third argument to the function specific execution context.

See struct x1f4_attributes_type.

The function_set.fix method in the struct x1f4_attributes_type expression parsing context is used only to retrieve the function specific execution contexts and only for functions requiring specific execution contexts (and marked by the X1f4_E4_TEXT_LINK bit in their flags field defitions).

A reference to a two long array of void pointers is passed to the methods implementing the logic of functions having a specific execution context instead the general execution context. The first element of the array is the function specific execution context, while the second is the general execution context.

Assuming `method13' implementing the logic of function having a specific execution context, the two contexts can be accessed as in:

method13(void *context, void *output, void **input)
    void **the_contexts;

    the_contexts = context;

    the_contexts[0] is the function specific context

    the_contexts[1] is the general execution context