Class ExternalFunction

src/function_context.py:6–81

A context that describes a source-code point of view of an external function, using references from/to it. Attributes ---------- hints (set): set of possible match (bin) candidates represented as eas xrefs (set): set of xrefs to this external function, as seen in the source

import config.libc_config      as libc

class ExternalFunction(CodeContext):
    """A context that describes a source-code point of view of an external function, using references from/to it.

    Attributes
    ----------
        hints (set): set of possible match (bin) candidates represented as eas
        xrefs (set): set of xrefs to this external function, as seen in the source project
    """

    def __init__(self, name):
        """Create a class instance using only the name (ea is unknown until we will have a match).

        Args:
            name (str): name of the external function
        """
        super(ExternalFunction, self).__init__(name)
        self.hints = None
        self.xrefs = set()

    # Overridden base function
    def declareMatch(self, match):
        """Declare a match between our source external and a binary function.

        Args:
            match (ea): the match ea
        """
        self.match = match

    # Overridden base function
    def valid(self):
        """Check if the function is still valid (still active).

        Return Value:
            True iff the function still exists in the file matching process
        """
        return True

    def addXref(self, xref):
        """Add an xref to the function.

        Args:
            xref (CodeContext): code context that calls (xrefs) our function
        """
        self.xrefs.add(xref)

    def removeXref(self, xref):
        """Remove an xref from the function (the caller was probably found irrelevant for our search).

        Args:
            xref (CodeContext): code context that calls (xrefs) our function
        """
        if xref in self.xrefs:
            self.xrefs.remove(xref)

    def used(self):
        """Check if our external function is still used by active functions.

        Return Value: