view hgext/fsmonitor/pywatchman/load.py @ 36034:f3d8f61c425d

gpg: print unknown key IDs in their entirety

Shortening the key is nice in theory but it results in ambiguity which can
be exploited.  Therefore, when encountering an unknown key ID we should
print the whole ID returned by gpg.  This may or may not be the whole key,
however it will match the user preference set in gpg configuration.

Furthermore, the key ID shortening had a couple of issues:

(1) it truncated the key ID (dropping the last digit and outputting only 15
    hex digits) making it very hard to find the correct key on a key server

(2) since only 15 digits were fed into shortkey(), it always emitted the
    ui.debug() warning

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from __future__ import absolute_import
from __future__ import division
from __future__ import print_function
# no unicode literals

try:
    from . import bser
except ImportError:
    from . import pybser as bser

import ctypes

EMPTY_HEADER = b"\x00\x01\x05\x00\x00\x00\x00"


def _read_bytes(fp, buf):
    """Read bytes from a file-like object

    @param fp: File-like object that implements read(int)
    @type fp: file

    @param buf: Buffer to read into
    @type buf: bytes

    @return: buf
    """

    # Do the first read without resizing the input buffer
    offset = 0
    remaining = len(buf)
    while remaining > 0:
        l = fp.readinto((ctypes.c_char * remaining).from_buffer(buf, offset))
        if l is None or l == 0:
            return offset
        offset += l
        remaining -= l
    return offset


def load(fp, mutable=True, value_encoding=None, value_errors=None):
    """Deserialize a BSER-encoded blob.

    @param fp: The file-object to deserialize.
    @type file:

    @param mutable: Whether to return mutable results.
    @type mutable: bool

    @param value_encoding: Optional codec to use to decode values. If
                           unspecified or None, return values as bytestrings.
    @type value_encoding: str

    @param value_errors: Optional error handler for codec. 'strict' by default.
                         The other most common argument is 'surrogateescape' on
                         Python 3. If value_encoding is None, this is ignored.
    @type value_errors: str
    """
    buf = ctypes.create_string_buffer(8192)
    SNIFF_BUFFER_SIZE = len(EMPTY_HEADER)
    header = (ctypes.c_char * SNIFF_BUFFER_SIZE).from_buffer(buf)
    read_len = _read_bytes(fp, header)
    if read_len < len(header):
        return None

    total_len = bser.pdu_len(buf)
    if total_len > len(buf):
        ctypes.resize(buf, total_len)

    body = (ctypes.c_char * (total_len - len(header))).from_buffer(
        buf, len(header))
    read_len = _read_bytes(fp, body)
    if read_len < len(body):
        raise RuntimeError('bser data ended early')

    return bser.loads(
        (ctypes.c_char * total_len).from_buffer(buf, 0),
        mutable,
        value_encoding,
        value_errors)