# Caller-is functions.
# Copyright (C) 2008-2020 Free Software Foundation, Inc.

# This program is free software; you can redistribute it and/or modify
# it under the terms of the GNU General Public License as published by
# the Free Software Foundation; either version 3 of the License, or
# (at your option) any later version.
#
# This program is distributed in the hope that it will be useful,
# but WITHOUT ANY WARRANTY; without even the implied warranty of
# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
# GNU General Public License for more details.
#
# You should have received a copy of the GNU General Public License
# along with this program.  If not, see <http://www.gnu.org/licenses/>.

import gdb
import re

class CallerIs(gdb.Function):
    """Check the calling function's name.

Usage: $_caller_is (NAME [, NUMBER-OF-FRAMES])

Arguments:

  NAME: The name of the function to search for.

  NUMBER-OF-FRAMES: How many stack frames to traverse back from the currently
    selected frame to compare with.  If the value is greater than the depth of
    the stack from that point then the result is False.
    The default is 1.

Returns:
  True if the function's name at the specified frame is equal to NAME."""

    def __init__(self):
        super(CallerIs, self).__init__("_caller_is")

    def invoke(self, name, nframes = 1):
        if nframes < 0:
            raise ValueError("nframes must be >= 0")
        frame = gdb.selected_frame()
        while nframes > 0:
            frame = frame.older()
            if frame is None:
                return False
            nframes = nframes - 1
        return frame.name() == name.string()

class CallerMatches(gdb.Function):
    """Compare the calling function's name with a regexp.

Usage: $_caller_matches (REGEX [, NUMBER-OF-FRAMES])

Arguments:

  REGEX: The regular expression to compare the function's name with.

  NUMBER-OF-FRAMES: How many stack frames to traverse back from the currently
    selected frame to compare with.  If the value is greater than the depth of
    the stack from that point then the result is False.
    The default is 1.

Returns:
  True if the function's name at the specified frame matches REGEX."""

    def __init__(self):
        super(CallerMatches, self).__init__("_caller_matches")

    def invoke(self, name, nframes = 1):
        if nframes < 0:
            raise ValueError("nframes must be >= 0")
        frame = gdb.selected_frame()
        while nframes > 0:
            frame = frame.older()
            if frame is None:
                return False
            nframes = nframes - 1
        return re.match(name.string(), frame.name()) is not None

class AnyCallerIs(gdb.Function):
    """Check all calling function's names.

Usage: $_any_caller_is (NAME [, NUMBER-OF-FRAMES])

Arguments:

  NAME: The name of the function to search for.

  NUMBER-OF-FRAMES: How many stack frames to traverse back from the currently
    selected frame to compare with.  If the value is greater than the depth of
    the stack from that point then the result is False.
    The default is 1.

Returns:
  True if any function's name is equal to NAME."""

    def __init__(self):
        super(AnyCallerIs, self).__init__("_any_caller_is")

    def invoke(self, name, nframes = 1):
        if nframes < 0:
            raise ValueError("nframes must be >= 0")
        frame = gdb.selected_frame()
        while nframes >= 0:
            if frame.name() == name.string():
                return True 
            frame = frame.older()
            if frame is None:
                return False
            nframes = nframes - 1
        return False

class AnyCallerMatches(gdb.Function):
    """Compare all calling function's names with a regexp.

Usage: $_any_caller_matches (REGEX [, NUMBER-OF-FRAMES])

Arguments:

  REGEX: The regular expression to compare the function's name with.

  NUMBER-OF-FRAMES: How many stack frames to traverse back from the currently
    selected frame to compare with.  If the value is greater than the depth of
    the stack from that point then the result is False.
    The default is 1.

Returns:
  True if any function's name matches REGEX."""

    def __init__(self):
        super(AnyCallerMatches, self).__init__("_any_caller_matches")

    def invoke(self, name, nframes = 1):
        if nframes < 0:
            raise ValueError("nframes must be >= 0")
        frame = gdb.selected_frame()
        name_re = re.compile(name.string())
        while nframes >= 0:
            if name_re.match(frame.name()) is not None:
                return True
            frame = frame.older()
            if frame is None:
                return False
            nframes = nframes - 1
        return False

CallerIs()
CallerMatches()
AnyCallerIs()
AnyCallerMatches()
