vfs: use 'vfs' module directly in 'mercurial.unionrepo'
Now that the 'vfs' classes moved in their own module, lets use the new module
directly. We update code iteratively to help with possible bisect needs in the
future.
# Copyright 2014-present 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
import inspect
import math
import os
import socket
import subprocess
import time
# Sometimes it's really hard to get Python extensions to compile,
# so fall back to a pure Python implementation.
try:
from . import bser
# Demandimport causes modules to be loaded lazily. Force the load now
# so that we can fall back on pybser if bser doesn't exist
bser.pdu_info
except ImportError:
from . import pybser as bser
from . import (
capabilities,
compat,
encoding,
load,
)
if os.name == 'nt':
import ctypes
import ctypes.wintypes
wintypes = ctypes.wintypes
GENERIC_READ = 0x80000000
GENERIC_WRITE = 0x40000000
FILE_FLAG_OVERLAPPED = 0x40000000
OPEN_EXISTING = 3
INVALID_HANDLE_VALUE = -1
FORMAT_MESSAGE_FROM_SYSTEM = 0x00001000
FORMAT_MESSAGE_ALLOCATE_BUFFER = 0x00000100
FORMAT_MESSAGE_IGNORE_INSERTS = 0x00000200
WAIT_FAILED = 0xFFFFFFFF
WAIT_TIMEOUT = 0x00000102
WAIT_OBJECT_0 = 0x00000000
WAIT_IO_COMPLETION = 0x000000C0
INFINITE = 0xFFFFFFFF
# Overlapped I/O operation is in progress. (997)
ERROR_IO_PENDING = 0x000003E5
# The pointer size follows the architecture
# We use WPARAM since this type is already conditionally defined
ULONG_PTR = ctypes.wintypes.WPARAM
class OVERLAPPED(ctypes.Structure):
_fields_ = [
("Internal", ULONG_PTR), ("InternalHigh", ULONG_PTR),
("Offset", wintypes.DWORD), ("OffsetHigh", wintypes.DWORD),
("hEvent", wintypes.HANDLE)
]
def __init__(self):
self.Internal = 0
self.InternalHigh = 0
self.Offset = 0
self.OffsetHigh = 0
self.hEvent = 0
LPDWORD = ctypes.POINTER(wintypes.DWORD)
CreateFile = ctypes.windll.kernel32.CreateFileA
CreateFile.argtypes = [wintypes.LPSTR, wintypes.DWORD, wintypes.DWORD,
wintypes.LPVOID, wintypes.DWORD, wintypes.DWORD,
wintypes.HANDLE]
CreateFile.restype = wintypes.HANDLE
CloseHandle = ctypes.windll.kernel32.CloseHandle
CloseHandle.argtypes = [wintypes.HANDLE]
CloseHandle.restype = wintypes.BOOL
ReadFile = ctypes.windll.kernel32.ReadFile
ReadFile.argtypes = [wintypes.HANDLE, wintypes.LPVOID, wintypes.DWORD,
LPDWORD, ctypes.POINTER(OVERLAPPED)]
ReadFile.restype = wintypes.BOOL
WriteFile = ctypes.windll.kernel32.WriteFile
WriteFile.argtypes = [wintypes.HANDLE, wintypes.LPVOID, wintypes.DWORD,
LPDWORD, ctypes.POINTER(OVERLAPPED)]
WriteFile.restype = wintypes.BOOL
GetLastError = ctypes.windll.kernel32.GetLastError
GetLastError.argtypes = []
GetLastError.restype = wintypes.DWORD
SetLastError = ctypes.windll.kernel32.SetLastError
SetLastError.argtypes = [wintypes.DWORD]
SetLastError.restype = None
FormatMessage = ctypes.windll.kernel32.FormatMessageA
FormatMessage.argtypes = [wintypes.DWORD, wintypes.LPVOID, wintypes.DWORD,
wintypes.DWORD, ctypes.POINTER(wintypes.LPSTR),
wintypes.DWORD, wintypes.LPVOID]
FormatMessage.restype = wintypes.DWORD
LocalFree = ctypes.windll.kernel32.LocalFree
GetOverlappedResult = ctypes.windll.kernel32.GetOverlappedResult
GetOverlappedResult.argtypes = [wintypes.HANDLE,
ctypes.POINTER(OVERLAPPED), LPDWORD,
wintypes.BOOL]
GetOverlappedResult.restype = wintypes.BOOL
GetOverlappedResultEx = getattr(ctypes.windll.kernel32,
'GetOverlappedResultEx', None)
if GetOverlappedResultEx is not None:
GetOverlappedResultEx.argtypes = [wintypes.HANDLE,
ctypes.POINTER(OVERLAPPED), LPDWORD,
wintypes.DWORD, wintypes.BOOL]
GetOverlappedResultEx.restype = wintypes.BOOL
WaitForSingleObjectEx = ctypes.windll.kernel32.WaitForSingleObjectEx
WaitForSingleObjectEx.argtypes = [wintypes.HANDLE, wintypes.DWORD, wintypes.BOOL]
WaitForSingleObjectEx.restype = wintypes.DWORD
CreateEvent = ctypes.windll.kernel32.CreateEventA
CreateEvent.argtypes = [LPDWORD, wintypes.BOOL, wintypes.BOOL,
wintypes.LPSTR]
CreateEvent.restype = wintypes.HANDLE
# Windows Vista is the minimum supported client for CancelIoEx.
CancelIoEx = ctypes.windll.kernel32.CancelIoEx
CancelIoEx.argtypes = [wintypes.HANDLE, ctypes.POINTER(OVERLAPPED)]
CancelIoEx.restype = wintypes.BOOL
# 2 bytes marker, 1 byte int size, 8 bytes int64 value
sniff_len = 13
# This is a helper for debugging the client.
_debugging = False
if _debugging:
def log(fmt, *args):
print('[%s] %s' %
(time.strftime("%a, %d %b %Y %H:%M:%S", time.gmtime()),
fmt % args[:]))
else:
def log(fmt, *args):
pass
def _win32_strerror(err):
""" expand a win32 error code into a human readable message """
# FormatMessage will allocate memory and assign it here
buf = ctypes.c_char_p()
FormatMessage(
FORMAT_MESSAGE_FROM_SYSTEM | FORMAT_MESSAGE_ALLOCATE_BUFFER
| FORMAT_MESSAGE_IGNORE_INSERTS, None, err, 0, buf, 0, None)
try:
return buf.value
finally:
LocalFree(buf)
class WatchmanError(Exception):
def __init__(self, msg=None, cmd=None):
self.msg = msg
self.cmd = cmd
def setCommand(self, cmd):
self.cmd = cmd
def __str__(self):
if self.cmd:
return '%s, while executing %s' % (self.msg, self.cmd)
return self.msg
class WatchmanEnvironmentError(WatchmanError):
def __init__(self, msg, errno, errmsg, cmd=None):
super(WatchmanEnvironmentError, self).__init__(
'{0}: errno={1} errmsg={2}'.format(msg, errno, errmsg),
cmd)
class SocketConnectError(WatchmanError):
def __init__(self, sockpath, exc):
super(SocketConnectError, self).__init__(
'unable to connect to %s: %s' % (sockpath, exc))
self.sockpath = sockpath
self.exc = exc
class SocketTimeout(WatchmanError):
"""A specialized exception raised for socket timeouts during communication to/from watchman.
This makes it easier to implement non-blocking loops as callers can easily distinguish
between a routine timeout and an actual error condition.
Note that catching WatchmanError will also catch this as it is a super-class, so backwards
compatibility in exception handling is preserved.
"""
class CommandError(WatchmanError):
"""error returned by watchman
self.msg is the message returned by watchman.
"""
def __init__(self, msg, cmd=None):
super(CommandError, self).__init__(
'watchman command error: %s' % (msg, ),
cmd,
)
class Transport(object):
""" communication transport to the watchman server """
buf = None
def close(self):
""" tear it down """
raise NotImplementedError()
def readBytes(self, size):
""" read size bytes """
raise NotImplementedError()
def write(self, buf):
""" write some data """
raise NotImplementedError()
def setTimeout(self, value):
pass
def readLine(self):
""" read a line
Maintains its own buffer, callers of the transport should not mix
calls to readBytes and readLine.
"""
if self.buf is None:
self.buf = []
# Buffer may already have a line if we've received unilateral
# response(s) from the server
if len(self.buf) == 1 and b"\n" in self.buf[0]:
(line, b) = self.buf[0].split(b"\n", 1)
self.buf = [b]
return line
while True:
b = self.readBytes(4096)
if b"\n" in b:
result = b''.join(self.buf)
(line, b) = b.split(b"\n", 1)
self.buf = [b]
return result + line
self.buf.append(b)
class Codec(object):
""" communication encoding for the watchman server """
transport = None
def __init__(self, transport):
self.transport = transport
def receive(self):
raise NotImplementedError()
def send(self, *args):
raise NotImplementedError()
def setTimeout(self, value):
self.transport.setTimeout(value)
class UnixSocketTransport(Transport):
""" local unix domain socket transport """
sock = None
def __init__(self, sockpath, timeout):
self.sockpath = sockpath
self.timeout = timeout
sock = socket.socket(socket.AF_UNIX, socket.SOCK_STREAM)
try:
sock.settimeout(self.timeout)
sock.connect(self.sockpath)
self.sock = sock
except socket.error as e:
sock.close()
raise SocketConnectError(self.sockpath, e)
def close(self):
self.sock.close()
self.sock = None
def setTimeout(self, value):
self.timeout = value
self.sock.settimeout(self.timeout)
def readBytes(self, size):
try:
buf = [self.sock.recv(size)]
if not buf[0]:
raise WatchmanError('empty watchman response')
return buf[0]
except socket.timeout:
raise SocketTimeout('timed out waiting for response')
def write(self, data):
try:
self.sock.sendall(data)
except socket.timeout:
raise SocketTimeout('timed out sending query command')
def _get_overlapped_result_ex_impl(pipe, olap, nbytes, millis, alertable):
""" Windows 7 and earlier does not support GetOverlappedResultEx. The
alternative is to use GetOverlappedResult and wait for read or write
operation to complete. This is done be using CreateEvent and
WaitForSingleObjectEx. CreateEvent, WaitForSingleObjectEx
and GetOverlappedResult are all part of Windows API since WindowsXP.
This is the exact same implementation that can be found in the watchman
source code (see get_overlapped_result_ex_impl in stream_win.c). This
way, maintenance should be simplified.
"""
log('Preparing to wait for maximum %dms', millis )
if millis != 0:
waitReturnCode = WaitForSingleObjectEx(olap.hEvent, millis, alertable)
if waitReturnCode == WAIT_OBJECT_0:
# Event is signaled, overlapped IO operation result should be available.
pass
elif waitReturnCode == WAIT_IO_COMPLETION:
# WaitForSingleObjectEx returnes because the system added an I/O completion
# routine or an asynchronous procedure call (APC) to the thread queue.
SetLastError(WAIT_IO_COMPLETION)
pass
elif waitReturnCode == WAIT_TIMEOUT:
# We reached the maximum allowed wait time, the IO operation failed
# to complete in timely fashion.
SetLastError(WAIT_TIMEOUT)
return False
elif waitReturnCode == WAIT_FAILED:
# something went wrong calling WaitForSingleObjectEx
err = GetLastError()
log('WaitForSingleObjectEx failed: %s', _win32_strerror(err))
return False
else:
# unexpected situation deserving investigation.
err = GetLastError()
log('Unexpected error: %s', _win32_strerror(err))
return False
return GetOverlappedResult(pipe, olap, nbytes, False)
class WindowsNamedPipeTransport(Transport):
""" connect to a named pipe """
def __init__(self, sockpath, timeout):
self.sockpath = sockpath
self.timeout = int(math.ceil(timeout * 1000))
self._iobuf = None
self.pipe = CreateFile(sockpath, GENERIC_READ | GENERIC_WRITE, 0, None,
OPEN_EXISTING, FILE_FLAG_OVERLAPPED, None)
if self.pipe == INVALID_HANDLE_VALUE:
self.pipe = None
self._raise_win_err('failed to open pipe %s' % sockpath,
GetLastError())
# event for the overlapped I/O operations
self._waitable = CreateEvent(None, True, False, None)
if self._waitable is None:
self._raise_win_err('CreateEvent failed', GetLastError())
self._get_overlapped_result_ex = GetOverlappedResultEx
if (os.getenv('WATCHMAN_WIN7_COMPAT') == '1' or
self._get_overlapped_result_ex is None):
self._get_overlapped_result_ex = _get_overlapped_result_ex_impl
def _raise_win_err(self, msg, err):
raise IOError('%s win32 error code: %d %s' %
(msg, err, _win32_strerror(err)))
def close(self):
if self.pipe:
log('Closing pipe')
CloseHandle(self.pipe)
self.pipe = None
if self._waitable is not None:
# We release the handle for the event
CloseHandle(self._waitable)
self._waitable = None
def setTimeout(self, value):
# convert to milliseconds
self.timeout = int(value * 1000)
def readBytes(self, size):
""" A read can block for an unbounded amount of time, even if the
kernel reports that the pipe handle is signalled, so we need to
always perform our reads asynchronously
"""
# try to satisfy the read from any buffered data
if self._iobuf:
if size >= len(self._iobuf):
res = self._iobuf
self.buf = None
return res
res = self._iobuf[:size]
self._iobuf = self._iobuf[size:]
return res
# We need to initiate a read
buf = ctypes.create_string_buffer(size)
olap = OVERLAPPED()
olap.hEvent = self._waitable
log('made read buff of size %d', size)
# ReadFile docs warn against sending in the nread parameter for async
# operations, so we always collect it via GetOverlappedResultEx
immediate = ReadFile(self.pipe, buf, size, None, olap)
if not immediate:
err = GetLastError()
if err != ERROR_IO_PENDING:
self._raise_win_err('failed to read %d bytes' % size,
GetLastError())
nread = wintypes.DWORD()
if not self._get_overlapped_result_ex(self.pipe, olap, nread,
0 if immediate else self.timeout,
True):
err = GetLastError()
CancelIoEx(self.pipe, olap)
if err == WAIT_TIMEOUT:
log('GetOverlappedResultEx timedout')
raise SocketTimeout('timed out after waiting %dms for read' %
self.timeout)
log('GetOverlappedResultEx reports error %d', err)
self._raise_win_err('error while waiting for read', err)
nread = nread.value
if nread == 0:
# Docs say that named pipes return 0 byte when the other end did
# a zero byte write. Since we don't ever do that, the only
# other way this shows up is if the client has gotten in a weird
# state, so let's bail out
CancelIoEx(self.pipe, olap)
raise IOError('Async read yielded 0 bytes; unpossible!')
# Holds precisely the bytes that we read from the prior request
buf = buf[:nread]
returned_size = min(nread, size)
if returned_size == nread:
return buf
# keep any left-overs around for a later read to consume
self._iobuf = buf[returned_size:]
return buf[:returned_size]
def write(self, data):
olap = OVERLAPPED()
olap.hEvent = self._waitable
immediate = WriteFile(self.pipe, ctypes.c_char_p(data), len(data),
None, olap)
if not immediate:
err = GetLastError()
if err != ERROR_IO_PENDING:
self._raise_win_err('failed to write %d bytes' % len(data),
GetLastError())
# Obtain results, waiting if needed
nwrote = wintypes.DWORD()
if self._get_overlapped_result_ex(self.pipe, olap, nwrote,
0 if immediate else self.timeout,
True):
log('made write of %d bytes', nwrote.value)
return nwrote.value
err = GetLastError()
# It's potentially unsafe to allow the write to continue after
# we unwind, so let's make a best effort to avoid that happening
CancelIoEx(self.pipe, olap)
if err == WAIT_TIMEOUT:
raise SocketTimeout('timed out after waiting %dms for write' %
self.timeout)
self._raise_win_err('error while waiting for write of %d bytes' %
len(data), err)
class CLIProcessTransport(Transport):
""" open a pipe to the cli to talk to the service
This intended to be used only in the test harness!
The CLI is an oddball because we only support JSON input
and cannot send multiple commands through the same instance,
so we spawn a new process for each command.
We disable server spawning for this implementation, again, because
it is intended to be used only in our test harness. You really
should not need to use the CLI transport for anything real.
While the CLI can output in BSER, our Transport interface doesn't
support telling this instance that it should do so. That effectively
limits this implementation to JSON input and output only at this time.
It is the responsibility of the caller to set the send and
receive codecs appropriately.
"""
proc = None
closed = True
def __init__(self, sockpath, timeout):
self.sockpath = sockpath
self.timeout = timeout
def close(self):
if self.proc:
if self.proc.pid is not None:
self.proc.kill()
self.proc.stdin.close()
self.proc.stdout.close()
self.proc = None
def _connect(self):
if self.proc:
return self.proc
args = [
'watchman',
'--sockname={0}'.format(self.sockpath),
'--logfile=/BOGUS',
'--statefile=/BOGUS',
'--no-spawn',
'--no-local',
'--no-pretty',
'-j',
]
self.proc = subprocess.Popen(args,
stdin=subprocess.PIPE,
stdout=subprocess.PIPE)
return self.proc
def readBytes(self, size):
self._connect()
res = self.proc.stdout.read(size)
if res == '':
raise WatchmanError('EOF on CLI process transport')
return res
def write(self, data):
if self.closed:
self.close()
self.closed = False
self._connect()
res = self.proc.stdin.write(data)
self.proc.stdin.close()
self.closed = True
return res
class BserCodec(Codec):
""" use the BSER encoding. This is the default, preferred codec """
def _loads(self, response):
return bser.loads(response) # Defaults to BSER v1
def receive(self):
buf = [self.transport.readBytes(sniff_len)]
if not buf[0]:
raise WatchmanError('empty watchman response')
_1, _2, elen = bser.pdu_info(buf[0])
rlen = len(buf[0])
while elen > rlen:
buf.append(self.transport.readBytes(elen - rlen))
rlen += len(buf[-1])
response = b''.join(buf)
try:
res = self._loads(response)
return res
except ValueError as e:
raise WatchmanError('watchman response decode error: %s' % e)
def send(self, *args):
cmd = bser.dumps(*args) # Defaults to BSER v1
self.transport.write(cmd)
class ImmutableBserCodec(BserCodec):
""" use the BSER encoding, decoding values using the newer
immutable object support """
def _loads(self, response):
return bser.loads(response, False) # Defaults to BSER v1
class Bser2WithFallbackCodec(BserCodec):
""" use BSER v2 encoding """
def __init__(self, transport):
super(Bser2WithFallbackCodec, self).__init__(transport)
# Once the server advertises support for bser-v2 we should switch this
# to 'required' on Python 3.
self.send(["version", {"optional": ["bser-v2"]}])
capabilities = self.receive()
if 'error' in capabilities:
raise Exception('Unsupported BSER version')
if capabilities['capabilities']['bser-v2']:
self.bser_version = 2
self.bser_capabilities = 0
else:
self.bser_version = 1
self.bser_capabilities = 0
def _loads(self, response):
return bser.loads(response)
def receive(self):
buf = [self.transport.readBytes(sniff_len)]
if not buf[0]:
raise WatchmanError('empty watchman response')
recv_bser_version, recv_bser_capabilities, elen = bser.pdu_info(buf[0])
if hasattr(self, 'bser_version'):
# Readjust BSER version and capabilities if necessary
self.bser_version = max(self.bser_version, recv_bser_version)
self.capabilities = self.bser_capabilities & recv_bser_capabilities
rlen = len(buf[0])
while elen > rlen:
buf.append(self.transport.readBytes(elen - rlen))
rlen += len(buf[-1])
response = b''.join(buf)
try:
res = self._loads(response)
return res
except ValueError as e:
raise WatchmanError('watchman response decode error: %s' % e)
def send(self, *args):
if hasattr(self, 'bser_version'):
cmd = bser.dumps(*args, version=self.bser_version,
capabilities=self.bser_capabilities)
else:
cmd = bser.dumps(*args)
self.transport.write(cmd)
class JsonCodec(Codec):
""" Use json codec. This is here primarily for testing purposes """
json = None
def __init__(self, transport):
super(JsonCodec, self).__init__(transport)
# optional dep on json, only if JsonCodec is used
import json
self.json = json
def receive(self):
line = self.transport.readLine()
try:
# In Python 3, json.loads is a transformation from Unicode string to
# objects possibly containing Unicode strings. We typically expect
# the JSON blob to be ASCII-only with non-ASCII characters escaped,
# but it's possible we might get non-ASCII bytes that are valid
# UTF-8.
if compat.PYTHON3:
line = line.decode('utf-8')
return self.json.loads(line)
except Exception as e:
print(e, line)
raise
def send(self, *args):
cmd = self.json.dumps(*args)
# In Python 3, json.dumps is a transformation from objects possibly
# containing Unicode strings to Unicode string. Even with (the default)
# ensure_ascii=True, dumps returns a Unicode string.
if compat.PYTHON3:
cmd = cmd.encode('ascii')
self.transport.write(cmd + b"\n")
class client(object):
""" Handles the communication with the watchman service """
sockpath = None
transport = None
sendCodec = None
recvCodec = None
sendConn = None
recvConn = None
subs = {} # Keyed by subscription name
sub_by_root = {} # Keyed by root, then by subscription name
logs = [] # When log level is raised
unilateral = ['log', 'subscription']
tport = None
useImmutableBser = None
def __init__(self,
sockpath=None,
timeout=1.0,
transport=None,
sendEncoding=None,
recvEncoding=None,
useImmutableBser=False):
self.sockpath = sockpath
self.timeout = timeout
self.useImmutableBser = useImmutableBser
if inspect.isclass(transport) and issubclass(transport, Transport):
self.transport = transport
else:
transport = transport or os.getenv('WATCHMAN_TRANSPORT') or 'local'
if transport == 'local' and os.name == 'nt':
self.transport = WindowsNamedPipeTransport
elif transport == 'local':
self.transport = UnixSocketTransport
elif transport == 'cli':
self.transport = CLIProcessTransport
if sendEncoding is None:
sendEncoding = 'json'
if recvEncoding is None:
recvEncoding = sendEncoding
else:
raise WatchmanError('invalid transport %s' % transport)
sendEncoding = str(sendEncoding or os.getenv('WATCHMAN_ENCODING') or
'bser')
recvEncoding = str(recvEncoding or os.getenv('WATCHMAN_ENCODING') or
'bser')
self.recvCodec = self._parseEncoding(recvEncoding)
self.sendCodec = self._parseEncoding(sendEncoding)
def _parseEncoding(self, enc):
if enc == 'bser':
if self.useImmutableBser:
return ImmutableBserCodec
return BserCodec
elif enc == 'experimental-bser-v2':
return Bser2WithFallbackCodec
elif enc == 'json':
return JsonCodec
else:
raise WatchmanError('invalid encoding %s' % enc)
def _hasprop(self, result, name):
if self.useImmutableBser:
return hasattr(result, name)
return name in result
def _resolvesockname(self):
# if invoked via a trigger, watchman will set this env var; we
# should use it unless explicitly set otherwise
path = os.getenv('WATCHMAN_SOCK')
if path:
return path
cmd = ['watchman', '--output-encoding=bser', 'get-sockname']
try:
args = dict(stdout=subprocess.PIPE,
stderr=subprocess.PIPE,
close_fds=os.name != 'nt')
if os.name == 'nt':
# if invoked via an application with graphical user interface,
# this call will cause a brief command window pop-up.
# Using the flag STARTF_USESHOWWINDOW to avoid this behavior.
startupinfo = subprocess.STARTUPINFO()
startupinfo.dwFlags |= subprocess.STARTF_USESHOWWINDOW
args['startupinfo'] = startupinfo
p = subprocess.Popen(cmd, **args)
except OSError as e:
raise WatchmanError('"watchman" executable not in PATH (%s)', e)
stdout, stderr = p.communicate()
exitcode = p.poll()
if exitcode:
raise WatchmanError("watchman exited with code %d" % exitcode)
result = bser.loads(stdout)
if b'error' in result:
raise WatchmanError('get-sockname error: %s' % result['error'])
return result[b'sockname']
def _connect(self):
""" establish transport connection """
if self.recvConn:
return
if self.sockpath is None:
self.sockpath = self._resolvesockname()
self.tport = self.transport(self.sockpath, self.timeout)
self.sendConn = self.sendCodec(self.tport)
self.recvConn = self.recvCodec(self.tport)
def __del__(self):
self.close()
def close(self):
if self.tport:
self.tport.close()
self.tport = None
self.recvConn = None
self.sendConn = None
def receive(self):
""" receive the next PDU from the watchman service
If the client has activated subscriptions or logs then
this PDU may be a unilateral PDU sent by the service to
inform the client of a log event or subscription change.
It may also simply be the response portion of a request
initiated by query.
There are clients in production that subscribe and call
this in a loop to retrieve all subscription responses,
so care should be taken when making changes here.
"""
self._connect()
result = self.recvConn.receive()
if self._hasprop(result, 'error'):
error = result['error']
if compat.PYTHON3 and isinstance(self.recvConn, BserCodec):
error = result['error'].decode('utf-8', 'surrogateescape')
raise CommandError(error)
if self._hasprop(result, 'log'):
log = result['log']
if compat.PYTHON3 and isinstance(self.recvConn, BserCodec):
log = log.decode('utf-8', 'surrogateescape')
self.logs.append(log)
if self._hasprop(result, 'subscription'):
sub = result['subscription']
if not (sub in self.subs):
self.subs[sub] = []
self.subs[sub].append(result)
# also accumulate in {root,sub} keyed store
root = os.path.normcase(result['root'])
if not root in self.sub_by_root:
self.sub_by_root[root] = {}
if not sub in self.sub_by_root[root]:
self.sub_by_root[root][sub] = []
self.sub_by_root[root][sub].append(result)
return result
def isUnilateralResponse(self, res):
if 'unilateral' in res and res['unilateral']:
return True
# Fall back to checking for known unilateral responses
for k in self.unilateral:
if k in res:
return True
return False
def getLog(self, remove=True):
""" Retrieve buffered log data
If remove is true the data will be removed from the buffer.
Otherwise it will be left in the buffer
"""
res = self.logs
if remove:
self.logs = []
return res
def getSubscription(self, name, remove=True, root=None):
""" Retrieve the data associated with a named subscription
If remove is True (the default), the subscription data is removed
from the buffer. Otherwise the data is returned but left in
the buffer.
Returns None if there is no data associated with `name`
If root is not None, then only return the subscription
data that matches both root and name. When used in this way,
remove processing impacts both the unscoped and scoped stores
for the subscription data.
"""
if compat.PYTHON3 and issubclass(self.recvCodec, BserCodec):
# People may pass in Unicode strings here -- but currently BSER only
# returns bytestrings. Deal with that.
if isinstance(root, str):
root = encoding.encode_local(root)
if isinstance(name, str):
name = name.encode('utf-8')
if root is not None:
if not root in self.sub_by_root:
return None
if not name in self.sub_by_root[root]:
return None
sub = self.sub_by_root[root][name]
if remove:
del self.sub_by_root[root][name]
# don't let this grow unbounded
if name in self.subs:
del self.subs[name]
return sub
if not (name in self.subs):
return None
sub = self.subs[name]
if remove:
del self.subs[name]
return sub
def query(self, *args):
""" Send a query to the watchman service and return the response
This call will block until the response is returned.
If any unilateral responses are sent by the service in between
the request-response they will be buffered up in the client object
and NOT returned via this method.
"""
log('calling client.query')
self._connect()
try:
self.sendConn.send(args)
res = self.receive()
while self.isUnilateralResponse(res):
res = self.receive()
return res
except EnvironmentError as ee:
# When we can depend on Python 3, we can use PEP 3134
# exception chaining here.
raise WatchmanEnvironmentError(
'I/O error communicating with watchman daemon',
ee.errno,
ee.strerror,
args)
except WatchmanError as ex:
ex.setCommand(args)
raise
def capabilityCheck(self, optional=None, required=None):
""" Perform a server capability check """
res = self.query('version', {
'optional': optional or [],
'required': required or []
})
if not self._hasprop(res, 'capabilities'):
# Server doesn't support capabilities, so we need to
# synthesize the results based on the version
capabilities.synthesize(res, optional)
if 'error' in res:
raise CommandError(res['error'])
return res
def setTimeout(self, value):
self.recvConn.setTimeout(value)
self.sendConn.setTimeout(value)