##// END OF EJS Templates
wireproto: add streams to frame-based protocol...
wireproto: add streams to frame-based protocol Previously, the frame-based protocol was just a series of frames, with each frame associated with a request ID. In order to scale the protocol, we'll want to enable the use of compression. While it is possible to enable compression at the socket/pipe level, this has its disadvantages. The big one is it undermines the point of frames being standalone, atomic units that can be read and written: if you add compression above the framing protocol, you are back to having a stream-based protocol as opposed to something frame-based. So in order to preserve frames, compression needs to occur at the frame payload level. Compressing each frame's payload individually will limit compression ratios because the window size of the compressor will be limited by the max frame size, which is 32-64kb as currently defined. It will also add CPU overhead, as it is more efficient for compressors to operate on fewer, larger blocks of data than more, smaller blocks. So compressing each frame independently is out. This means we need to compress each frame's payload as if it is part of a larger stream. The simplest approach is to have 1 stream per connection. This could certainly work. However, it has disadvantages (documented below). We could also have 1 stream per RPC/command invocation. (This is the model HTTP/2 goes with.) This also has disadvantages. The main disadvantage to one global stream is that it has the very real potential to create CPU bottlenecks doing compression. Networks are only getting faster and the performance of single CPU cores has been relatively flat. Newer compression formats like zstandard offer better CPU cycle efficiency than predecessors like zlib. But it still all too common to saturate your CPU with compression overhead long before you saturate the network pipe. The main disadvantage with streams per request is that you can't reap the benefits of the compression context for multiple requests. For example, if you send 1000 RPC requests (or HTTP/2 requests for that matter), the response to each would have its own compression context. The overall size of the raw responses would be larger because compression contexts wouldn't be able to reference data from another request or response. The approach for streams as implemented in this commit is to support N streams per connection and for streams to potentially span requests and responses. As explained by the added internals docs, this facilitates servers and clients delegating independent streams and compression to independent threads / CPU cores. This helps alleviate the CPU bottleneck of compression. This design also allows compression contexts to be reused across requests/responses. This can result in improved compression ratios and less overhead for compressors and decompressors having to build new contexts. Another feature that was defined was the ability for individual frames within a stream to declare whether that individual frame's payload uses the content encoding (read: compression) defined by the stream. The idea here is that some servers may serve data from a combination of caches and dynamic resolution. Data coming from caches may be pre-compressed. We want to facilitate servers being able to essentially stream bytes from caches to the wire with minimal overhead. Being able to mix and match with frames are compressed within a stream enables these types of advanced server functionality. This commit defines the new streams mechanism. Basic code for supporting streams in frames has been added. But that code is seriously lacking and doesn't fully conform to the defined protocol. For example, we don't close any streams. And support for content encoding within streams is not yet implemented. The change was rather invasive and I didn't think it would be reasonable to implement the entire feature in a single commit. For the record, I would have loved to reuse an existing multiplexing protocol to build the new wire protocol on top of. However, I couldn't find a protocol that offers the performance and scaling characteristics that I desired. Namely, it should support multiple compression contexts to facilitate scaling out to multiple CPU cores and compression contexts should be able to live longer than single RPC requests. HTTP/2 *almost* fits the bill. But the semantics of HTTP message exchange state that streams can only live for a single request-response. We /could/ tunnel on top of HTTP/2 streams and frames with HEADER and DATA frames. But there's no guarantee that HTTP/2 libraries and proxies would allow us to use HTTP/2 streams and frames without the HTTP message exchange semantics defined in RFC 7540 Section 8. Other RPC protocols like gRPC tunnel are built on top of HTTP/2 and thus preserve its semantics of stream per RPC invocation. Even QUIC does this. We could attempt to invent a higher-level stream that spans HTTP/2 streams. But this would be violating HTTP/2 because there is no guarantee that HTTP/2 streams are routed to the same server. The best we can do - which is what this protocol does - is shoehorn all request and response data into a single HTTP message and create streams within. At that point, we've defined a Content-Type in HTTP parlance. It just so happens our media type can also work as a standalone, stream-based protocol, without leaning on HTTP or similar protocol. Differential Revision: https://phab.mercurial-scm.org/D2907

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win32.py
640 lines | 21.6 KiB | text/x-python | PythonLexer
# win32.py - utility functions that use win32 API
#
# Copyright 2005-2009 Matt Mackall <mpm@selenic.com> and others
#
# This software may be used and distributed according to the terms of the
# GNU General Public License version 2 or any later version.
from __future__ import absolute_import
import ctypes
import ctypes.wintypes as wintypes
import errno
import msvcrt
import os
import random
import subprocess
from . import (
encoding,
pycompat,
)
_kernel32 = ctypes.windll.kernel32
_advapi32 = ctypes.windll.advapi32
_user32 = ctypes.windll.user32
_crypt32 = ctypes.windll.crypt32
_BOOL = ctypes.c_long
_WORD = ctypes.c_ushort
_DWORD = ctypes.c_ulong
_UINT = ctypes.c_uint
_LONG = ctypes.c_long
_LPCSTR = _LPSTR = ctypes.c_char_p
_HANDLE = ctypes.c_void_p
_HWND = _HANDLE
_PCCERT_CONTEXT = ctypes.c_void_p
_MAX_PATH = wintypes.MAX_PATH
_INVALID_HANDLE_VALUE = _HANDLE(-1).value
# GetLastError
_ERROR_SUCCESS = 0
_ERROR_NO_MORE_FILES = 18
_ERROR_INVALID_PARAMETER = 87
_ERROR_BROKEN_PIPE = 109
_ERROR_INSUFFICIENT_BUFFER = 122
# WPARAM is defined as UINT_PTR (unsigned type)
# LPARAM is defined as LONG_PTR (signed type)
if ctypes.sizeof(ctypes.c_long) == ctypes.sizeof(ctypes.c_void_p):
_WPARAM = ctypes.c_ulong
_LPARAM = ctypes.c_long
elif ctypes.sizeof(ctypes.c_longlong) == ctypes.sizeof(ctypes.c_void_p):
_WPARAM = ctypes.c_ulonglong
_LPARAM = ctypes.c_longlong
class _FILETIME(ctypes.Structure):
_fields_ = [('dwLowDateTime', _DWORD),
('dwHighDateTime', _DWORD)]
class _BY_HANDLE_FILE_INFORMATION(ctypes.Structure):
_fields_ = [('dwFileAttributes', _DWORD),
('ftCreationTime', _FILETIME),
('ftLastAccessTime', _FILETIME),
('ftLastWriteTime', _FILETIME),
('dwVolumeSerialNumber', _DWORD),
('nFileSizeHigh', _DWORD),
('nFileSizeLow', _DWORD),
('nNumberOfLinks', _DWORD),
('nFileIndexHigh', _DWORD),
('nFileIndexLow', _DWORD)]
# CreateFile
_FILE_SHARE_READ = 0x00000001
_FILE_SHARE_WRITE = 0x00000002
_FILE_SHARE_DELETE = 0x00000004
_OPEN_EXISTING = 3
_FILE_FLAG_BACKUP_SEMANTICS = 0x02000000
# SetFileAttributes
_FILE_ATTRIBUTE_NORMAL = 0x80
_FILE_ATTRIBUTE_NOT_CONTENT_INDEXED = 0x2000
# Process Security and Access Rights
_PROCESS_QUERY_INFORMATION = 0x0400
# GetExitCodeProcess
_STILL_ACTIVE = 259
class _STARTUPINFO(ctypes.Structure):
_fields_ = [('cb', _DWORD),
('lpReserved', _LPSTR),
('lpDesktop', _LPSTR),
('lpTitle', _LPSTR),
('dwX', _DWORD),
('dwY', _DWORD),
('dwXSize', _DWORD),
('dwYSize', _DWORD),
('dwXCountChars', _DWORD),
('dwYCountChars', _DWORD),
('dwFillAttribute', _DWORD),
('dwFlags', _DWORD),
('wShowWindow', _WORD),
('cbReserved2', _WORD),
('lpReserved2', ctypes.c_char_p),
('hStdInput', _HANDLE),
('hStdOutput', _HANDLE),
('hStdError', _HANDLE)]
class _PROCESS_INFORMATION(ctypes.Structure):
_fields_ = [('hProcess', _HANDLE),
('hThread', _HANDLE),
('dwProcessId', _DWORD),
('dwThreadId', _DWORD)]
_CREATE_NO_WINDOW = 0x08000000
_SW_HIDE = 0
class _COORD(ctypes.Structure):
_fields_ = [('X', ctypes.c_short),
('Y', ctypes.c_short)]
class _SMALL_RECT(ctypes.Structure):
_fields_ = [('Left', ctypes.c_short),
('Top', ctypes.c_short),
('Right', ctypes.c_short),
('Bottom', ctypes.c_short)]
class _CONSOLE_SCREEN_BUFFER_INFO(ctypes.Structure):
_fields_ = [('dwSize', _COORD),
('dwCursorPosition', _COORD),
('wAttributes', _WORD),
('srWindow', _SMALL_RECT),
('dwMaximumWindowSize', _COORD)]
_STD_OUTPUT_HANDLE = _DWORD(-11).value
_STD_ERROR_HANDLE = _DWORD(-12).value
# CERT_TRUST_STATUS dwErrorStatus
CERT_TRUST_IS_PARTIAL_CHAIN = 0x10000
# CertCreateCertificateContext encodings
X509_ASN_ENCODING = 0x00000001
PKCS_7_ASN_ENCODING = 0x00010000
# These structs are only complete enough to achieve what we need.
class CERT_CHAIN_CONTEXT(ctypes.Structure):
_fields_ = (
("cbSize", _DWORD),
# CERT_TRUST_STATUS struct
("dwErrorStatus", _DWORD),
("dwInfoStatus", _DWORD),
("cChain", _DWORD),
("rgpChain", ctypes.c_void_p),
("cLowerQualityChainContext", _DWORD),
("rgpLowerQualityChainContext", ctypes.c_void_p),
("fHasRevocationFreshnessTime", _BOOL),
("dwRevocationFreshnessTime", _DWORD),
)
class CERT_USAGE_MATCH(ctypes.Structure):
_fields_ = (
("dwType", _DWORD),
# CERT_ENHKEY_USAGE struct
("cUsageIdentifier", _DWORD),
("rgpszUsageIdentifier", ctypes.c_void_p), # LPSTR *
)
class CERT_CHAIN_PARA(ctypes.Structure):
_fields_ = (
("cbSize", _DWORD),
("RequestedUsage", CERT_USAGE_MATCH),
("RequestedIssuancePolicy", CERT_USAGE_MATCH),
("dwUrlRetrievalTimeout", _DWORD),
("fCheckRevocationFreshnessTime", _BOOL),
("dwRevocationFreshnessTime", _DWORD),
("pftCacheResync", ctypes.c_void_p), # LPFILETIME
("pStrongSignPara", ctypes.c_void_p), # PCCERT_STRONG_SIGN_PARA
("dwStrongSignFlags", _DWORD),
)
# types of parameters of C functions used (required by pypy)
_crypt32.CertCreateCertificateContext.argtypes = [_DWORD, # cert encoding
ctypes.c_char_p, # cert
_DWORD] # cert size
_crypt32.CertCreateCertificateContext.restype = _PCCERT_CONTEXT
_crypt32.CertGetCertificateChain.argtypes = [
ctypes.c_void_p, # HCERTCHAINENGINE
_PCCERT_CONTEXT,
ctypes.c_void_p, # LPFILETIME
ctypes.c_void_p, # HCERTSTORE
ctypes.c_void_p, # PCERT_CHAIN_PARA
_DWORD,
ctypes.c_void_p, # LPVOID
ctypes.c_void_p # PCCERT_CHAIN_CONTEXT *
]
_crypt32.CertGetCertificateChain.restype = _BOOL
_crypt32.CertFreeCertificateContext.argtypes = [_PCCERT_CONTEXT]
_crypt32.CertFreeCertificateContext.restype = _BOOL
_kernel32.CreateFileA.argtypes = [_LPCSTR, _DWORD, _DWORD, ctypes.c_void_p,
_DWORD, _DWORD, _HANDLE]
_kernel32.CreateFileA.restype = _HANDLE
_kernel32.GetFileInformationByHandle.argtypes = [_HANDLE, ctypes.c_void_p]
_kernel32.GetFileInformationByHandle.restype = _BOOL
_kernel32.CloseHandle.argtypes = [_HANDLE]
_kernel32.CloseHandle.restype = _BOOL
try:
_kernel32.CreateHardLinkA.argtypes = [_LPCSTR, _LPCSTR, ctypes.c_void_p]
_kernel32.CreateHardLinkA.restype = _BOOL
except AttributeError:
pass
_kernel32.SetFileAttributesA.argtypes = [_LPCSTR, _DWORD]
_kernel32.SetFileAttributesA.restype = _BOOL
_DRIVE_UNKNOWN = 0
_DRIVE_NO_ROOT_DIR = 1
_DRIVE_REMOVABLE = 2
_DRIVE_FIXED = 3
_DRIVE_REMOTE = 4
_DRIVE_CDROM = 5
_DRIVE_RAMDISK = 6
_kernel32.GetDriveTypeA.argtypes = [_LPCSTR]
_kernel32.GetDriveTypeA.restype = _UINT
_kernel32.GetVolumeInformationA.argtypes = [_LPCSTR, ctypes.c_void_p, _DWORD,
ctypes.c_void_p, ctypes.c_void_p, ctypes.c_void_p, ctypes.c_void_p, _DWORD]
_kernel32.GetVolumeInformationA.restype = _BOOL
_kernel32.GetVolumePathNameA.argtypes = [_LPCSTR, ctypes.c_void_p, _DWORD]
_kernel32.GetVolumePathNameA.restype = _BOOL
_kernel32.OpenProcess.argtypes = [_DWORD, _BOOL, _DWORD]
_kernel32.OpenProcess.restype = _HANDLE
_kernel32.GetExitCodeProcess.argtypes = [_HANDLE, ctypes.c_void_p]
_kernel32.GetExitCodeProcess.restype = _BOOL
_kernel32.GetLastError.argtypes = []
_kernel32.GetLastError.restype = _DWORD
_kernel32.GetModuleFileNameA.argtypes = [_HANDLE, ctypes.c_void_p, _DWORD]
_kernel32.GetModuleFileNameA.restype = _DWORD
_kernel32.CreateProcessA.argtypes = [_LPCSTR, _LPCSTR, ctypes.c_void_p,
ctypes.c_void_p, _BOOL, _DWORD, ctypes.c_void_p, _LPCSTR, ctypes.c_void_p,
ctypes.c_void_p]
_kernel32.CreateProcessA.restype = _BOOL
_kernel32.ExitProcess.argtypes = [_UINT]
_kernel32.ExitProcess.restype = None
_kernel32.GetCurrentProcessId.argtypes = []
_kernel32.GetCurrentProcessId.restype = _DWORD
_SIGNAL_HANDLER = ctypes.WINFUNCTYPE(_BOOL, _DWORD)
_kernel32.SetConsoleCtrlHandler.argtypes = [_SIGNAL_HANDLER, _BOOL]
_kernel32.SetConsoleCtrlHandler.restype = _BOOL
_kernel32.SetConsoleMode.argtypes = [_HANDLE, _DWORD]
_kernel32.SetConsoleMode.restype = _BOOL
_kernel32.GetConsoleMode.argtypes = [_HANDLE, ctypes.c_void_p]
_kernel32.GetConsoleMode.restype = _BOOL
_kernel32.GetStdHandle.argtypes = [_DWORD]
_kernel32.GetStdHandle.restype = _HANDLE
_kernel32.GetConsoleScreenBufferInfo.argtypes = [_HANDLE, ctypes.c_void_p]
_kernel32.GetConsoleScreenBufferInfo.restype = _BOOL
_advapi32.GetUserNameA.argtypes = [ctypes.c_void_p, ctypes.c_void_p]
_advapi32.GetUserNameA.restype = _BOOL
_user32.GetWindowThreadProcessId.argtypes = [_HANDLE, ctypes.c_void_p]
_user32.GetWindowThreadProcessId.restype = _DWORD
_user32.ShowWindow.argtypes = [_HANDLE, ctypes.c_int]
_user32.ShowWindow.restype = _BOOL
_WNDENUMPROC = ctypes.WINFUNCTYPE(_BOOL, _HWND, _LPARAM)
_user32.EnumWindows.argtypes = [_WNDENUMPROC, _LPARAM]
_user32.EnumWindows.restype = _BOOL
_kernel32.PeekNamedPipe.argtypes = [_HANDLE, ctypes.c_void_p, _DWORD,
ctypes.c_void_p, ctypes.c_void_p, ctypes.c_void_p]
_kernel32.PeekNamedPipe.restype = _BOOL
def _raiseoserror(name):
# Force the code to a signed int to avoid an 'int too large' error.
# See https://bugs.python.org/issue28474
code = _kernel32.GetLastError()
if code > 0x7fffffff:
code -= 2**32
err = ctypes.WinError(code=code)
raise OSError(err.errno, '%s: %s' % (name,
encoding.strtolocal(err.strerror)))
def _getfileinfo(name):
fh = _kernel32.CreateFileA(name, 0,
_FILE_SHARE_READ | _FILE_SHARE_WRITE | _FILE_SHARE_DELETE,
None, _OPEN_EXISTING, _FILE_FLAG_BACKUP_SEMANTICS, None)
if fh == _INVALID_HANDLE_VALUE:
_raiseoserror(name)
try:
fi = _BY_HANDLE_FILE_INFORMATION()
if not _kernel32.GetFileInformationByHandle(fh, ctypes.byref(fi)):
_raiseoserror(name)
return fi
finally:
_kernel32.CloseHandle(fh)
def checkcertificatechain(cert, build=True):
'''Tests the given certificate to see if there is a complete chain to a
trusted root certificate. As a side effect, missing certificates are
downloaded and installed unless ``build=False``. True is returned if a
chain to a trusted root exists (even if built on the fly), otherwise
False. NB: A chain to a trusted root does NOT imply that the certificate
is valid.
'''
chainctxptr = ctypes.POINTER(CERT_CHAIN_CONTEXT)
pchainctx = chainctxptr()
chainpara = CERT_CHAIN_PARA(cbSize=ctypes.sizeof(CERT_CHAIN_PARA),
RequestedUsage=CERT_USAGE_MATCH())
certctx = _crypt32.CertCreateCertificateContext(X509_ASN_ENCODING, cert,
len(cert))
if certctx is None:
_raiseoserror('CertCreateCertificateContext')
flags = 0
if not build:
flags |= 0x100 # CERT_CHAIN_DISABLE_AUTH_ROOT_AUTO_UPDATE
try:
# Building the certificate chain will update root certs as necessary.
if not _crypt32.CertGetCertificateChain(None, # hChainEngine
certctx, # pCertContext
None, # pTime
None, # hAdditionalStore
ctypes.byref(chainpara),
flags,
None, # pvReserved
ctypes.byref(pchainctx)):
_raiseoserror('CertGetCertificateChain')
chainctx = pchainctx.contents
return chainctx.dwErrorStatus & CERT_TRUST_IS_PARTIAL_CHAIN == 0
finally:
if pchainctx:
_crypt32.CertFreeCertificateChain(pchainctx)
_crypt32.CertFreeCertificateContext(certctx)
def oslink(src, dst):
try:
if not _kernel32.CreateHardLinkA(dst, src, None):
_raiseoserror(src)
except AttributeError: # Wine doesn't support this function
_raiseoserror(src)
def nlinks(name):
'''return number of hardlinks for the given file'''
return _getfileinfo(name).nNumberOfLinks
def samefile(path1, path2):
'''Returns whether path1 and path2 refer to the same file or directory.'''
res1 = _getfileinfo(path1)
res2 = _getfileinfo(path2)
return (res1.dwVolumeSerialNumber == res2.dwVolumeSerialNumber
and res1.nFileIndexHigh == res2.nFileIndexHigh
and res1.nFileIndexLow == res2.nFileIndexLow)
def samedevice(path1, path2):
'''Returns whether path1 and path2 are on the same device.'''
res1 = _getfileinfo(path1)
res2 = _getfileinfo(path2)
return res1.dwVolumeSerialNumber == res2.dwVolumeSerialNumber
def peekpipe(pipe):
handle = msvcrt.get_osfhandle(pipe.fileno())
avail = _DWORD()
if not _kernel32.PeekNamedPipe(handle, None, 0, None, ctypes.byref(avail),
None):
err = _kernel32.GetLastError()
if err == _ERROR_BROKEN_PIPE:
return 0
raise ctypes.WinError(err)
return avail.value
def testpid(pid):
'''return True if pid is still running or unable to
determine, False otherwise'''
h = _kernel32.OpenProcess(_PROCESS_QUERY_INFORMATION, False, pid)
if h:
try:
status = _DWORD()
if _kernel32.GetExitCodeProcess(h, ctypes.byref(status)):
return status.value == _STILL_ACTIVE
finally:
_kernel32.CloseHandle(h)
return _kernel32.GetLastError() != _ERROR_INVALID_PARAMETER
def executablepath():
'''return full path of hg.exe'''
size = 600
buf = ctypes.create_string_buffer(size + 1)
len = _kernel32.GetModuleFileNameA(None, ctypes.byref(buf), size)
if len == 0:
raise ctypes.WinError() # Note: WinError is a function
elif len == size:
raise ctypes.WinError(_ERROR_INSUFFICIENT_BUFFER)
return buf.value
def getvolumename(path):
"""Get the mount point of the filesystem from a directory or file
(best-effort)
Returns None if we are unsure. Raises OSError on ENOENT, EPERM, etc.
"""
# realpath() calls GetFullPathName()
realpath = os.path.realpath(path)
# allocate at least MAX_PATH long since GetVolumePathName('c:\\', buf, 4)
# somehow fails on Windows XP
size = max(len(realpath), _MAX_PATH) + 1
buf = ctypes.create_string_buffer(size)
if not _kernel32.GetVolumePathNameA(realpath, ctypes.byref(buf), size):
raise ctypes.WinError() # Note: WinError is a function
return buf.value
def getfstype(path):
"""Get the filesystem type name from a directory or file (best-effort)
Returns None if we are unsure. Raises OSError on ENOENT, EPERM, etc.
"""
volume = getvolumename(path)
t = _kernel32.GetDriveTypeA(volume)
if t == _DRIVE_REMOTE:
return 'cifs'
elif t not in (_DRIVE_REMOVABLE, _DRIVE_FIXED, _DRIVE_CDROM,
_DRIVE_RAMDISK):
return None
size = _MAX_PATH + 1
name = ctypes.create_string_buffer(size)
if not _kernel32.GetVolumeInformationA(volume, None, 0, None, None, None,
ctypes.byref(name), size):
raise ctypes.WinError() # Note: WinError is a function
return name.value
def getuser():
'''return name of current user'''
size = _DWORD(300)
buf = ctypes.create_string_buffer(size.value + 1)
if not _advapi32.GetUserNameA(ctypes.byref(buf), ctypes.byref(size)):
raise ctypes.WinError()
return buf.value
_signalhandler = []
def setsignalhandler():
'''Register a termination handler for console events including
CTRL+C. python signal handlers do not work well with socket
operations.
'''
def handler(event):
_kernel32.ExitProcess(1)
if _signalhandler:
return # already registered
h = _SIGNAL_HANDLER(handler)
_signalhandler.append(h) # needed to prevent garbage collection
if not _kernel32.SetConsoleCtrlHandler(h, True):
raise ctypes.WinError()
def hidewindow():
def callback(hwnd, pid):
wpid = _DWORD()
_user32.GetWindowThreadProcessId(hwnd, ctypes.byref(wpid))
if pid == wpid.value:
_user32.ShowWindow(hwnd, _SW_HIDE)
return False # stop enumerating windows
return True
pid = _kernel32.GetCurrentProcessId()
_user32.EnumWindows(_WNDENUMPROC(callback), pid)
def termsize():
# cmd.exe does not handle CR like a unix console, the CR is
# counted in the line length. On 80 columns consoles, if 80
# characters are written, the following CR won't apply on the
# current line but on the new one. Keep room for it.
width = 80 - 1
height = 25
# Query stderr to avoid problems with redirections
screenbuf = _kernel32.GetStdHandle(
_STD_ERROR_HANDLE) # don't close the handle returned
if screenbuf is None or screenbuf == _INVALID_HANDLE_VALUE:
return width, height
csbi = _CONSOLE_SCREEN_BUFFER_INFO()
if not _kernel32.GetConsoleScreenBufferInfo(
screenbuf, ctypes.byref(csbi)):
return width, height
width = csbi.srWindow.Right - csbi.srWindow.Left # don't '+ 1'
height = csbi.srWindow.Bottom - csbi.srWindow.Top + 1
return width, height
def enablevtmode():
'''Enable virtual terminal mode for the associated console. Return True if
enabled, else False.'''
ENABLE_VIRTUAL_TERMINAL_PROCESSING = 0x4
handle = _kernel32.GetStdHandle(_STD_OUTPUT_HANDLE) # don't close the handle
if handle == _INVALID_HANDLE_VALUE:
return False
mode = _DWORD(0)
if not _kernel32.GetConsoleMode(handle, ctypes.byref(mode)):
return False
if (mode.value & ENABLE_VIRTUAL_TERMINAL_PROCESSING) == 0:
mode.value |= ENABLE_VIRTUAL_TERMINAL_PROCESSING
if not _kernel32.SetConsoleMode(handle, mode):
return False
return True
def spawndetached(args):
# No standard library function really spawns a fully detached
# process under win32 because they allocate pipes or other objects
# to handle standard streams communications. Passing these objects
# to the child process requires handle inheritance to be enabled
# which makes really detached processes impossible.
si = _STARTUPINFO()
si.cb = ctypes.sizeof(_STARTUPINFO)
pi = _PROCESS_INFORMATION()
env = ''
for k in encoding.environ:
env += "%s=%s\0" % (k, encoding.environ[k])
if not env:
env = '\0'
env += '\0'
args = subprocess.list2cmdline(args)
res = _kernel32.CreateProcessA(
None, args, None, None, False, _CREATE_NO_WINDOW,
env, pycompat.getcwd(), ctypes.byref(si), ctypes.byref(pi))
if not res:
raise ctypes.WinError()
return pi.dwProcessId
def unlink(f):
'''try to implement POSIX' unlink semantics on Windows'''
if os.path.isdir(f):
# use EPERM because it is POSIX prescribed value, even though
# unlink(2) on directories returns EISDIR on Linux
raise IOError(errno.EPERM,
"Unlinking directory not permitted: '%s'" % f)
# POSIX allows to unlink and rename open files. Windows has serious
# problems with doing that:
# - Calling os.unlink (or os.rename) on a file f fails if f or any
# hardlinked copy of f has been opened with Python's open(). There is no
# way such a file can be deleted or renamed on Windows (other than
# scheduling the delete or rename for the next reboot).
# - Calling os.unlink on a file that has been opened with Mercurial's
# posixfile (or comparable methods) will delay the actual deletion of
# the file for as long as the file is held open. The filename is blocked
# during that time and cannot be used for recreating a new file under
# that same name ("zombie file"). Directories containing such zombie files
# cannot be removed or moved.
# A file that has been opened with posixfile can be renamed, so we rename
# f to a random temporary name before calling os.unlink on it. This allows
# callers to recreate f immediately while having other readers do their
# implicit zombie filename blocking on a temporary name.
for tries in xrange(10):
temp = '%s-%08x' % (f, random.randint(0, 0xffffffff))
try:
os.rename(f, temp) # raises OSError EEXIST if temp exists
break
except OSError as e:
if e.errno != errno.EEXIST:
raise
else:
raise IOError(errno.EEXIST, "No usable temporary filename found")
try:
os.unlink(temp)
except OSError:
# The unlink might have failed because the READONLY attribute may heave
# been set on the original file. Rename works fine with READONLY set,
# but not os.unlink. Reset all attributes and try again.
_kernel32.SetFileAttributesA(temp, _FILE_ATTRIBUTE_NORMAL)
try:
os.unlink(temp)
except OSError:
# The unlink might have failed due to some very rude AV-Scanners.
# Leaking a tempfile is the lesser evil than aborting here and
# leaving some potentially serious inconsistencies.
pass
def makedir(path, notindexed):
os.mkdir(path)
if notindexed:
_kernel32.SetFileAttributesA(path, _FILE_ATTRIBUTE_NOT_CONTENT_INDEXED)