# -*- coding: iso-8859-1 -*-
"""A lexical analyzer class for simple shell-like syntaxes."""
# Module and documentation by Eric S. Raymond, 21 Dec 1998
# Input stacking and error message cleanup added by ESR, March 2000
# push_source() and pop_source() made explicit by ESR, January 2001.
# Posix compliance, split(), string arguments, and
# iterator interface by Gustavo Niemeyer, April 2003.
from collections import deque
from cStringIO import StringIO
from StringIO import StringIO
__all__ = ["shlex", "split"]
"A lexical analyzer class for simple shell-like syntaxes."
def __init__(self, instream=None, infile=None, posix=False):
if isinstance(instream, basestring):
instream = StringIO(instream)
self.instream = sys.stdin
self.wordchars = ('abcdfeghijklmnopqrstuvwxyz'
'ABCDEFGHIJKLMNOPQRSTUVWXYZ0123456789_')
self.whitespace = ' \t\r\n'
self.whitespace_split = False
print 'shlex: reading from %s, line %d' \
% (self.instream, self.lineno)
def push_token(self, tok):
"Push a token onto the stack popped by the get_token method"
print "shlex: pushing token " + repr(tok)
self.pushback.appendleft(tok)
def push_source(self, newstream, newfile=None):
"Push an input source onto the lexer's input source stack."
if isinstance(newstream, basestring):
newstream = StringIO(newstream)
self.filestack.appendleft((self.infile, self.instream, self.lineno))
self.instream = newstream
print 'shlex: pushing to file %s' % (self.infile,)
print 'shlex: pushing to stream %s' % (self.instream,)
"Pop the input source stack."
(self.infile, self.instream, self.lineno) = self.filestack.popleft()
print 'shlex: popping to %s, line %d' \
% (self.instream, self.lineno)
"Get a token from the input stream (or from stack if it's nonempty)"
tok = self.pushback.popleft()
print "shlex: popping token " + repr(tok)
# No pushback. Get a token.
if self.source is not None:
while raw == self.source:
spec = self.sourcehook(self.read_token())
(newfile, newstream) = spec
self.push_source(newstream, newfile)
# Maybe we got EOF instead?
# Neither inclusion nor EOF
print "shlex: token=" + repr(raw)
nextchar = self.instream.read(1)
self.lineno = self.lineno + 1
print "shlex: in state", repr(self.state), \
"I see character:", repr(nextchar)
self.token = '' # past end of file
self.state = None # end of file
elif nextchar in self.whitespace:
print "shlex: I see whitespace in whitespace state"
if self.token or (self.posix and quoted):
break # emit current token
elif nextchar in self.commenters:
self.lineno = self.lineno + 1
elif self.posix and nextchar in self.escape:
elif nextchar in self.wordchars:
elif nextchar in self.quotes:
elif self.whitespace_split:
if self.token or (self.posix and quoted):
break # emit current token
elif self.state in self.quotes:
if not nextchar: # end of file
print "shlex: I see EOF in quotes state"
# XXX what error should be raised here?
raise ValueError, "No closing quotation"
if nextchar == self.state:
self.token = self.token + nextchar
elif self.posix and nextchar in self.escape and \
self.state in self.escapedquotes:
escapedstate = self.state
self.token = self.token + nextchar
elif self.state in self.escape:
if not nextchar: # end of file
print "shlex: I see EOF in escape state"
# XXX what error should be raised here?
raise ValueError, "No escaped character"
# In posix shells, only the quote itself or the escape
# character may be escaped within quotes.
if escapedstate in self.quotes and \
nextchar != self.state and nextchar != escapedstate:
self.token = self.token + self.state
self.token = self.token + nextchar
self.state = escapedstate
self.state = None # end of file
elif nextchar in self.whitespace:
print "shlex: I see whitespace in word state"
if self.token or (self.posix and quoted):
break # emit current token
elif nextchar in self.commenters:
self.lineno = self.lineno + 1
if self.token or (self.posix and quoted):
break # emit current token
elif self.posix and nextchar in self.quotes:
elif self.posix and nextchar in self.escape:
elif nextchar in self.wordchars or nextchar in self.quotes \
or self.whitespace_split:
self.token = self.token + nextchar
self.pushback.appendleft(nextchar)
print "shlex: I see punctuation in word state"
break # emit current token
if self.posix and not quoted and result == '':
print "shlex: raw token=" + repr(result)
print "shlex: raw token=EOF"
def sourcehook(self, newfile):
"Hook called on a filename to be sourced."
# This implements cpp-like semantics for relative-path inclusion.
if isinstance(self.infile, basestring) and not os.path.isabs(newfile):
newfile = os.path.join(os.path.dirname(self.infile), newfile)
return (newfile, open(newfile, "r"))
def error_leader(self, infile=None, lineno=None):
"Emit a C-compiler-like, Emacs-friendly error-message leader."
return "\"%s\", line %d: " % (infile, lineno)
def split(s, comments=False, posix=True):
lex = shlex(s, posix=posix)
lex.whitespace_split = True
if __name__ == '__main__':
lexer = shlex(open(file), file)
print "Token: " + repr(tt)
It is recommended that you Edit text format, this type of Fix handles quite a lot in one request
