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# $Id$
#
# Copyright (C) 1997 Klee Dienes <klee@mit.edu>
#
# This program is free software; you can redistribute it and/or modify
# it under the terms of the GNU General Public License as published by
# the Free Software Foundation; either version 2 of the License, or
# (at your option) any later version.
#
# This program is distributed in the hope that it will be useful,
# but WITHOUT ANY WARRANTY; without even the implied warranty of
# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
# GNU General Public License for more details.
#
# You should have received a copy of the GNU General Public License
# along with this program; if not, write to the Free Software
# Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
import sys, os, posix
class filter:
def __init__ (self, f, cmd):
(ri, wi) = os.pipe ()
(ro, wo) = os.pipe ()
(re, we) = os.pipe ()
self.filter = os.fork ()
if (self.filter == 0):
sys.argv[0] = sys.argv[0] + "[filter]"
for i in [ri, wi, ro, wo, re, we, 0, 1, 2]:
if (i not in [ri, wo, we]):
try:
os.close (i)
except posix.error, val:
pass
os.dup2 (ri, 0)
os.dup2 (wo, 1)
os.dup2 (we, 2)
os.system (cmd)
os.close (0)
os.close (1)
os.close (2)
os._exit (0)
self.writer = os.fork ()
if (self.writer == 0):
sys.argv[0] = sys.argv[0] + "[source]"
for i in [ri, wi, ro, wo, re, we, 0, 1, 2]:
if (i not in [wi]):
try:
os.close (i)
except posix.error, val:
pass
nf = os.fdopen (wi, 'w')
s = f.read ()
nf.write (s)
nf.flush ()
os.close (wi)
os._exit (0)
for i in [ri, wi, ro, wo, re, we]:
if (i not in [ro, re]):
os.close (i)
self.o = os.fdopen (ro, 'r')
self.pos = 0
self.blocksize = 16 * 1024
self.e = os.fdopen (re, 'r')
self.epos = 0
def isatty (self):
return 0
def seek (self, offset, mode = 0):
#print 'filter: seek %d (cur %d)' % (offset, self.tell ())
while (self.tell () < offset):
self.read (min (self.blocksize, offset - self.tell()))
if (offset < self.tell()):
raise ValueError, 'unable to seek backwards on stream'
def tell (self):
#print 'filter: tell %d' % self.pos
return self.pos
def read (self, n = -1):
r = self.o.read (n)
#print 'filter: read %d bytes from %d' % (len (r), self.pos)
self.pos = self.pos + len (r)
return r
def readline (self):
r = self.o.readline ()
self.pos = self.pos + len (r)
return r
def readlines (self):
rl = self.o.readlines ()
for r in rl:
self.pos = self.pos + len (r)
return rl
def stderr (self):
return self.e
def close (self):
self.o.close ()
self.e.close ()
pid, status = os.wait ()
#print pid, status
if (status != 0):
raise ValueError, 'sub-process returned error exit status %d' % status
pid, status = os.wait ()
#print pid, status
if (status != 0):
raise ValueError, 'sub-process returned error exit status %d' % status
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