hgext/fsmonitor/pywatchman/load.py
author Anton Shestakov <av6@dwimlabs.net>
Thu, 15 Feb 2018 21:14:57 +0800
changeset 36233 7ec5925c971e
parent 30656 16f4b341288d
child 43385 6469c23a40a2
permissions -rw-r--r--
hgweb: show dates recorded in obsolescence markers Dates of operations that obsolete commits are also important enough to be shown, but maybe not as important as original commit dates, that and also for brevity is why they are wrapped in a <span> with only "age" class. Provided that JS is enabled, such elements only show age (e.g. "3 months ago"), and the exact date is visible in a tooltip. Commits dates, on the other hand, show both date and age (the latter in parenthesis). Example result for f1a0933ce59e from hg-committed: obsolete: pruned by Yuya Nishihara <yuya@tcha.org> 13 days ago

# Copyright 2016 Facebook, Inc.
# All rights reserved.
#
# Redistribution and use in source and binary forms, with or without
# modification, are permitted provided that the following conditions are met:
#
#  * Redistributions of source code must retain the above copyright notice,
#    this list of conditions and the following disclaimer.
#
#  * Redistributions in binary form must reproduce the above copyright notice,
#    this list of conditions and the following disclaimer in the documentation
#    and/or other materials provided with the distribution.
#
#  * Neither the name Facebook nor the names of its contributors may be used to
#    endorse or promote products derived from this software without specific
#    prior written permission.
#
# THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
# AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
# IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
# DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE LIABLE
# FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
# DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR
# SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER
# CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
# OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
# OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.

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)