Protocol switch from using generators to stream-like objects.
This allows the the pull side to precisely control how much data is
read so that another encapsulation layer is not needed.
An http client gets a response with a finite size. Because ssh clients
need to keep the stream open, we must not read more data than is sent
in a response. But due to the streaming nature of the changegroup
scheme, only the piece that's parsing the data knows how far it's
allowed to read.
This means the generator scheme isn't fine-grained enough. Instead we
need file-like objects with a read(x) method. This switches everything
for push/pull over to using file-like objects rather than generators.
# util.py - utility functions and platform specfic implementations
#
# Copyright 2005 K. Thananchayan <thananck@yahoo.com>
#
# This software may be used and distributed according to the terms
# of the GNU General Public License, incorporated herein by reference.
import os
def unique(g):
seen = {}
for f in g:
if f not in seen:
seen[f] = 1
yield f
class CommandError(Exception): pass
def explain_exit(code):
"""return a 2-tuple (desc, code) describing a process's status"""
if os.WIFEXITED(code):
val = os.WEXITSTATUS(code)
return "exited with status %d" % val, val
elif os.WIFSIGNALED(code):
val = os.WTERMSIG(code)
return "killed by signal %d" % val, val
elif os.WIFSTOPPED(code):
val = os.STOPSIG(code)
return "stopped by signal %d" % val, val
raise ValueError("invalid exit code")
def system(cmd, errprefix=None):
"""execute a shell command that must succeed"""
rc = os.system(cmd)
if rc:
errmsg = "%s %s" % (os.path.basename(cmd.split(None, 1)[0]),
explain_exit(rc)[0])
if errprefix:
errmsg = "%s: %s" % (errprefix, errmsg)
raise CommandError(errmsg)
def rename(src, dst):
try:
os.rename(src, dst)
except:
os.unlink(dst)
os.rename(src, dst)
# Platfor specific varients
if os.name == 'nt':
nulldev = 'NUL:'
def is_exec(f, last):
return last
def set_exec(f, mode):
pass
def pconvert(path):
return path.replace("\\", "/")
def makelock(info, pathname):
ld = os.open(pathname, os.O_CREAT | os.O_WRONLY | os.O_EXCL)
os.write(ld, info)
os.close(ld)
def readlock(pathname):
return file(pathname).read()
else:
nulldev = '/dev/null'
def is_exec(f, last):
return (os.stat(f).st_mode & 0100 != 0)
def set_exec(f, mode):
s = os.stat(f).st_mode
if (s & 0100 != 0) == mode:
return
if mode:
# Turn on +x for every +r bit when making a file executable
# and obey umask.
umask = os.umask(0)
os.umask(umask)
os.chmod(f, s | (s & 0444) >> 2 & ~umask)
else:
os.chmod(f, s & 0666)
def pconvert(path):
return path
def makelock(info, pathname):
os.symlink(info, pathname)
def readlock(pathname):
return os.readlink(pathname)