view mercurial/commandserver.py @ 21883:87aa279f7073

largefiles: show also how many data entities are outgoing at "hg outgoing"

Before this patch, "hg outgoing --large" shows which largefiles are
changed or added in outgoing revisions only in the point of the view
of filenames.

For example, according to the list of outgoing largefiles shown in "hg
outgoing" output, users should expect that the former below costs much
more to upload outgoing largefiles than the latter.

  - outgoing revisions add a hundred largefiles, but all of them refer
    the same data entity

    in this case, only one data entity is outgoing, even though "hg
    summary" says that a hundred largefiles are outgoing.

  - a hundred outgoing revisions change only one largefile with
    distinct data

    in this case, a hundred data entities are outgoing, even though
    "hg summary" says that only one largefile is outgoing.

But the latter costs much more than the former, in fact.

This patch shows also how many data entities are outgoing at "hg
outgoing" by counting number of unique hash values for outgoing
largefiles.

When "--debug" is specified, this patch also shows what entities (in
hash) are outgoing for each largefiles listed up, for debug purpose.

In "ui.debugflag" route, "addfunc()" can append given "lfhash" to the
list "toupload[fn]" always without duplication check, because
de-duplication is already done in "_getoutgoings()".

# commandserver.py - communicate with Mercurial's API over a pipe
#
#  Copyright Matt Mackall <[e-mail]>
#
# This software may be used and distributed according to the terms of the
# GNU General Public License version 2 or any later version.

from i18n import _
import struct
import sys, os
import dispatch, encoding, util

logfile = None

def log(*args):
    if not logfile:
        return

    for a in args:
        logfile.write(str(a))

    logfile.flush()

class channeledoutput(object):
    """
    Write data from in_ to out in the following format:

    data length (unsigned int),
    data
    """
    def __init__(self, in_, out, channel):
        self.in_ = in_
        self.out = out
        self.channel = channel

    def write(self, data):
        if not data:
            return
        self.out.write(struct.pack('>cI', self.channel, len(data)))
        self.out.write(data)
        self.out.flush()

    def __getattr__(self, attr):
        if attr in ('isatty', 'fileno'):
            raise AttributeError(attr)
        return getattr(self.in_, attr)

class channeledinput(object):
    """
    Read data from in_.

    Requests for input are written to out in the following format:
    channel identifier - 'I' for plain input, 'L' line based (1 byte)
    how many bytes to send at most (unsigned int),

    The client replies with:
    data length (unsigned int), 0 meaning EOF
    data
    """

    maxchunksize = 4 * 1024

    def __init__(self, in_, out, channel):
        self.in_ = in_
        self.out = out
        self.channel = channel

    def read(self, size=-1):
        if size < 0:
            # if we need to consume all the clients input, ask for 4k chunks
            # so the pipe doesn't fill up risking a deadlock
            size = self.maxchunksize
            s = self._read(size, self.channel)
            buf = s
            while s:
                s = self._read(size, self.channel)
                buf += s

            return buf
        else:
            return self._read(size, self.channel)

    def _read(self, size, channel):
        if not size:
            return ''
        assert size > 0

        # tell the client we need at most size bytes
        self.out.write(struct.pack('>cI', channel, size))
        self.out.flush()

        length = self.in_.read(4)
        length = struct.unpack('>I', length)[0]
        if not length:
            return ''
        else:
            return self.in_.read(length)

    def readline(self, size=-1):
        if size < 0:
            size = self.maxchunksize
            s = self._read(size, 'L')
            buf = s
            # keep asking for more until there's either no more or
            # we got a full line
            while s and s[-1] != '\n':
                s = self._read(size, 'L')
                buf += s

            return buf
        else:
            return self._read(size, 'L')

    def __iter__(self):
        return self

    def next(self):
        l = self.readline()
        if not l:
            raise StopIteration
        return l

    def __getattr__(self, attr):
        if attr in ('isatty', 'fileno'):
            raise AttributeError(attr)
        return getattr(self.in_, attr)

class server(object):
    """
    Listens for commands on stdin, runs them and writes the output on a channel
    based stream to stdout.
    """
    def __init__(self, ui, repo, mode):
        self.cwd = os.getcwd()

        logpath = ui.config("cmdserver", "log", None)
        if logpath:
            global logfile
            if logpath == '-':
                # write log on a special 'd' (debug) channel
                logfile = channeledoutput(sys.stdout, sys.stdout, 'd')
            else:
                logfile = open(logpath, 'a')

        if repo:
            # the ui here is really the repo ui so take its baseui so we don't
            # end up with its local configuration
            self.ui = repo.baseui
            self.repo = repo
            self.repoui = repo.ui
        else:
            self.ui = ui
            self.repo = self.repoui = None

        if mode == 'pipe':
            self.cerr = channeledoutput(sys.stderr, sys.stdout, 'e')
            self.cout = channeledoutput(sys.stdout, sys.stdout, 'o')
            self.cin = channeledinput(sys.stdin, sys.stdout, 'I')
            self.cresult = channeledoutput(sys.stdout, sys.stdout, 'r')

            self.client = sys.stdin
        else:
            raise util.Abort(_('unknown mode %s') % mode)

    def _read(self, size):
        if not size:
            return ''

        data = self.client.read(size)

        # is the other end closed?
        if not data:
            raise EOFError

        return data

    def runcommand(self):
        """ reads a list of \0 terminated arguments, executes
        and writes the return code to the result channel """

        length = struct.unpack('>I', self._read(4))[0]
        if not length:
            args = []
        else:
            args = self._read(length).split('\0')

        # copy the uis so changes (e.g. --config or --verbose) don't
        # persist between requests
        copiedui = self.ui.copy()
        uis = [copiedui]
        if self.repo:
            self.repo.baseui = copiedui
            # clone ui without using ui.copy because this is protected
            repoui = self.repoui.__class__(self.repoui)
            repoui.copy = copiedui.copy # redo copy protection
            uis.append(repoui)
            self.repo.ui = self.repo.dirstate._ui = repoui
            self.repo.invalidateall()

        for ui in uis:
            # any kind of interaction must use server channels
            ui.setconfig('ui', 'nontty', 'true', 'commandserver')

        req = dispatch.request(args[:], copiedui, self.repo, self.cin,
                               self.cout, self.cerr)

        ret = (dispatch.dispatch(req) or 0) & 255 # might return None

        # restore old cwd
        if '--cwd' in args:
            os.chdir(self.cwd)

        self.cresult.write(struct.pack('>i', int(ret)))

    def getencoding(self):
        """ writes the current encoding to the result channel """
        self.cresult.write(encoding.encoding)

    def serveone(self):
        cmd = self.client.readline()[:-1]
        if cmd:
            handler = self.capabilities.get(cmd)
            if handler:
                handler(self)
            else:
                # clients are expected to check what commands are supported by
                # looking at the servers capabilities
                raise util.Abort(_('unknown command %s') % cmd)

        return cmd != ''

    capabilities = {'runcommand'  : runcommand,
                    'getencoding' : getencoding}

    def serve(self):
        hellomsg = 'capabilities: ' + ' '.join(sorted(self.capabilities))
        hellomsg += '\n'
        hellomsg += 'encoding: ' + encoding.encoding

        # write the hello msg in -one- chunk
        self.cout.write(hellomsg)

        try:
            while self.serveone():
                pass
        except EOFError:
            # we'll get here if the client disconnected while we were reading
            # its request
            return 1

        return 0