Merge pull request #49 from delphix/projects/merge-upstream/master

Merge remote-tracking branch '6.0/stage' into 'master'

drgn/helpers/__init__.py

@@ -6,228 +6,14 @@
 -------
 
 The ``drgn.helpers`` package contains subpackages which provide helpers for
-working with particular types of programs. Currently, there are only helpers
-for the Linux kernel. In the future, there may be helpers for, e.g., glibc and
-libstdc++.
-
-Generic Helpers
-===============
-
-The top-level ``drgn.helpers`` module provides generic helpers that may be
-useful for scripts or for implementing other helpers.
+working with particular types of programs. Currently, there are common helpers
+and helpers for the Linux kernel. In the future, there may be helpers for,
+e.g., glibc and libstdc++.
 """
 
-import enum
-import typing
-from typing import Container, Iterable, Tuple
-
-from drgn import IntegerLike, Type
-
 
 class ValidationError(Exception):
     """
     Error raised by a :ref:`validator <validators>` when an inconsistent or
     invalid state is detected.
     """
-
-
-def escape_ascii_character(
-    c: int,
-    escape_single_quote: bool = False,
-    escape_double_quote: bool = False,
-    escape_backslash: bool = False,
-) -> str:
-    """
-    Format an ASCII byte value as a character, possibly escaping it.
-    Non-printable characters are always escaped. Non-printable characters other
-    than ``\\0``, ``\\a``, ``\\b``, ``\\t``, ``\\n``, ``\\v``, ``\\f``, and
-    ``\\r`` are escaped in hexadecimal format (e.g., ``\\x7f``). By default,
-    printable characters are never escaped.
-
-    :param c: The character to escape.
-    :param escape_single_quote: Whether to escape single quotes to ``\\'``.
-    :param escape_double_quote: Whether to escape double quotes to ``\\"``.
-    :param escape_backslash: Whether to escape backslashes to ``\\\\``.
-    """
-    if c == 0:
-        return r"\0"
-    elif c == 7:
-        return r"\a"
-    elif c == 8:
-        return r"\b"
-    elif c == 9:
-        return r"\t"
-    elif c == 10:
-        return r"\n"
-    elif c == 11:
-        return r"\v"
-    elif c == 12:
-        return r"\f"
-    elif c == 13:
-        return r"\r"
-    elif escape_double_quote and c == 34:
-        return r"\""
-    elif escape_single_quote and c == 39:
-        return r"\'"
-    elif escape_backslash and c == 92:
-        return r"\\"
-    elif 32 <= c <= 126:
-        return chr(c)
-    else:
-        return f"\\x{c:02x}"
-
-
-def escape_ascii_string(
-    buffer: Iterable[int],
-    escape_single_quote: bool = False,
-    escape_double_quote: bool = False,
-    escape_backslash: bool = False,
-) -> str:
-    """
-    Escape an iterable of ASCII byte values (e.g., :class:`bytes` or
-    :class:`bytearray`). See :func:`escape_ascii_character()`.
-
-    :param buffer: The byte array.
-    """
-    return "".join(
-        escape_ascii_character(
-            c,
-            escape_single_quote=escape_single_quote,
-            escape_double_quote=escape_double_quote,
-            escape_backslash=escape_backslash,
-        )
-        for c in buffer
-    )
-
-
-def enum_type_to_class(
-    type: Type, name: str, exclude: Container[str] = (), prefix: str = ""
-) -> typing.Type[enum.IntEnum]:
-    """
-    Get an :class:`enum.IntEnum` class from an enumerated :class:`drgn.Type`.
-
-    :param type: The enumerated type to convert.
-    :param name: The name of the ``IntEnum`` type to create.
-    :param exclude: Container (e.g., list or set) of enumerator names to
-        exclude from the created ``IntEnum``.
-    :param prefix: Prefix to strip from the beginning of enumerator names.
-    """
-    if type.enumerators is None:
-        raise TypeError("enum type is incomplete")
-    enumerators = [
-        (name[len(prefix) :] if name.startswith(prefix) else name, value)
-        for (name, value) in type.enumerators
-        if name not in exclude
-    ]
-    return enum.IntEnum(name, enumerators)  # type: ignore  # python/mypy#4865
-
-
-def decode_flags(
-    value: IntegerLike,
-    flags: Iterable[Tuple[str, int]],
-    bit_numbers: bool = True,
-) -> str:
-    """
-    Get a human-readable representation of a bitmask of flags.
-
-    By default, flags are specified by their bit number:
-
-    >>> decode_flags(2, [("BOLD", 0), ("ITALIC", 1), ("UNDERLINE", 2)])
-    'ITALIC'
-
-    They can also be specified by their value:
-
-    >>> decode_flags(2, [("BOLD", 1), ("ITALIC", 2), ("UNDERLINE", 4)],
-    ...              bit_numbers=False)
-    'ITALIC'
-
-    Multiple flags are combined with "|":
-
-    >>> decode_flags(5, [("BOLD", 0), ("ITALIC", 1), ("UNDERLINE", 2)])
-    'BOLD|UNDERLINE'
-
-    If there are multiple names for the same bit, they are all included:
-
-    >>> decode_flags(2, [("SMALL", 0), ("BIG", 1), ("LARGE", 1)])
-    'BIG|LARGE'
-
-    If there are any unknown bits, their raw value is included:
-
-    >>> decode_flags(27, [("BOLD", 0), ("ITALIC", 1), ("UNDERLINE", 2)])
-    'BOLD|ITALIC|0x18'
-
-    Zero is returned verbatim:
-
-    >>> decode_flags(0, [("BOLD", 0), ("ITALIC", 1), ("UNDERLINE", 2)])
-    '0'
-
-    :param value: Bitmask to decode.
-    :param flags: List of flag names and their bit numbers or values.
-    :param bit_numbers: Whether *flags* specifies the bit numbers (where 0 is
-        the least significant bit) or values of the flags.
-    """
-    value = value.__index__()
-    if value == 0:
-        return "0"
-
-    parts = []
-    mask = 0
-    for name, flag in flags:
-        if bit_numbers:
-            flag = 1 << flag
-        if value & flag:
-            parts.append(name)
-            mask |= flag
-
-    if value & ~mask:
-        parts.append(hex(value & ~mask))
-
-    return "|".join(parts)
-
-
-def decode_enum_type_flags(
-    value: IntegerLike,
-    type: Type,
-    bit_numbers: bool = True,
-) -> str:
-    """
-    Get a human-readable representation of a bitmask of flags where the flags
-    are specified by an enumerated :class:`drgn.Type`.
-
-    This supports enums where the values are bit numbers:
-
-    >>> print(bits_enum)
-    enum style_bits {
-            BOLD = 0,
-            ITALIC = 1,
-            UNDERLINE = 2,
-    }
-    >>> decode_enum_type_flags(5, bits_enum)
-    'BOLD|UNDERLINE'
-
-    Or the values of the flags:
-
-    >>> print(flags_enum)
-    enum style_flags {
-            BOLD = 1,
-            ITALIC = 2,
-            UNDERLINE = 4,
-    }
-    >>> decode_enum_type_flags(5, flags_enum, bit_numbers=False)
-    'BOLD|UNDERLINE'
-
-    See :func:`decode_flags()`.
-
-    :param value: Bitmask to decode.
-    :param type: Enumerated type with bit numbers for enumerators.
-    :param bit_numbers: Whether the enumerator values specify the bit numbers
-         or values of the flags.
-    """
-    enumerators = type.enumerators
-    if enumerators is None:
-        raise TypeError("cannot decode incomplete enumerated type")
-    return decode_flags(
-        value,
-        enumerators,  # type: ignore  # python/mypy#592
-        bit_numbers,
-    )

drgn/helpers/common/__init__.py

@@ -0,0 +1,30 @@
+# Copyright (c) Meta Platforms, Inc. and affiliates.
+# SPDX-License-Identifier: GPL-3.0-or-later
+
+"""
+Common
+------
+
+The ``drgn.helpers.common`` package provides helpers that can be used with any
+program. The helpers are available from the individual modules in which they
+are defined and from this top-level package. E.g., the following are both
+valid:
+
+>>> from drgn.helpers.common.memory import identify_address
+>>> from drgn.helpers.common import identify_address
+
+Some of these helpers may have additional program-specific behavior but are
+otherwise generic.
+"""
+
+import importlib
+import pkgutil
+from typing import List
+
+__all__: List[str] = []
+for _module_info in pkgutil.iter_modules(__path__, prefix=__name__ + "."):
+    _submodule = importlib.import_module(_module_info.name)
+    _submodule_all = getattr(_submodule, "__all__", ())
+    __all__.extend(_submodule_all)
+    for _name in _submodule_all:
+        globals()[_name] = getattr(_submodule, _name)