##// END OF EJS Templates
tracked-key: remove the dual write and rename to tracked-hint...
tracked-key: remove the dual write and rename to tracked-hint The dual-write approach was mostly useless. As explained in the previous version of the help, the key had to be read twice before we could cache a value. However this "read twice" limitation actually also apply to any usage of the key. If some operation wants to rely of the "same value == same tracked set" property it would need to read the value before, and after running that operation (or at least, after, in all cases). So it cannot be sure the operation it did is "valid" until checking the key after the operation. As a resultat such operation can only be read-only or rollbackable. This reduce the utility of the "same value == same tracked set" a lot. So it seems simpler to drop the double write and to update the documentation to highlight that this file does not garantee race-free operation. As a result the "key" is demoted to a "hint". Documentation is updated accordingly. Differential Revision: https://phab.mercurial-scm.org/D12201

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hgclient.py
163 lines | 4.0 KiB | text/x-python | PythonLexer
# A minimal client for Mercurial's command server
from __future__ import absolute_import, print_function
import io
import os
import re
import signal
import socket
import struct
import subprocess
import sys
import time
if sys.version_info[0] >= 3:
stdout = sys.stdout.buffer
stderr = sys.stderr.buffer
stringio = io.BytesIO
def bprint(*args):
# remove b'' as well for ease of test migration
pargs = [re.sub(br'''\bb(['"])''', br'\1', b'%s' % a) for a in args]
stdout.write(b' '.join(pargs) + b'\n')
else:
import cStringIO
stdout = sys.stdout
stderr = sys.stderr
stringio = cStringIO.StringIO
bprint = print
def connectpipe(path=None, extraargs=()):
cmdline = [b'hg', b'serve', b'--cmdserver', b'pipe']
if path:
cmdline += [b'-R', path]
cmdline.extend(extraargs)
def tonative(cmdline):
if os.name != 'nt':
return cmdline
return [arg.decode("utf-8") for arg in cmdline]
server = subprocess.Popen(
tonative(cmdline), stdin=subprocess.PIPE, stdout=subprocess.PIPE
)
return server
class unixconnection(object):
def __init__(self, sockpath):
self.sock = sock = socket.socket(socket.AF_UNIX)
sock.connect(sockpath)
self.stdin = sock.makefile('wb')
self.stdout = sock.makefile('rb')
def wait(self):
self.stdin.close()
self.stdout.close()
self.sock.close()
class unixserver(object):
def __init__(self, sockpath, logpath=None, repopath=None):
self.sockpath = sockpath
cmdline = [b'hg', b'serve', b'--cmdserver', b'unix', b'-a', sockpath]
if repopath:
cmdline += [b'-R', repopath]
if logpath:
stdout = open(logpath, 'a')
stderr = subprocess.STDOUT
else:
stdout = stderr = None
self.server = subprocess.Popen(cmdline, stdout=stdout, stderr=stderr)
# wait for listen()
while self.server.poll() is None:
if os.path.exists(sockpath):
break
time.sleep(0.1)
def connect(self):
return unixconnection(self.sockpath)
def shutdown(self):
os.kill(self.server.pid, signal.SIGTERM)
self.server.wait()
def writeblock(server, data):
server.stdin.write(struct.pack(b'>I', len(data)))
server.stdin.write(data)
server.stdin.flush()
def readchannel(server):
data = server.stdout.read(5)
if not data:
raise EOFError
channel, length = struct.unpack('>cI', data)
if channel in b'IL':
return channel, length
else:
return channel, server.stdout.read(length)
def sep(text):
return text.replace(b'\\', b'/')
def runcommand(
server, args, output=stdout, error=stderr, input=None, outfilter=lambda x: x
):
bprint(b'*** runcommand', b' '.join(args))
stdout.flush()
server.stdin.write(b'runcommand\n')
writeblock(server, b'\0'.join(args))
if not input:
input = stringio()
while True:
ch, data = readchannel(server)
if ch == b'o':
output.write(outfilter(data))
output.flush()
elif ch == b'e':
error.write(data)
error.flush()
elif ch == b'I':
writeblock(server, input.read(data))
elif ch == b'L':
writeblock(server, input.readline(data))
elif ch == b'm':
bprint(b"message: %r" % data)
elif ch == b'r':
(ret,) = struct.unpack('>i', data)
if ret != 0:
bprint(b' [%d]' % ret)
return ret
else:
bprint(b"unexpected channel %c: %r" % (ch, data))
if ch.isupper():
return
def check(func, connect=connectpipe):
stdout.flush()
server = connect()
try:
return func(server)
finally:
server.stdin.close()
server.wait()
def checkwith(connect=connectpipe, **kwargs):
def wrap(func):
return check(func, lambda: connect(**kwargs))
return wrap