You can not select more than 25 topics
Topics must start with a letter or number, can include dashes ('-') and can be up to 35 characters long.
351 lines
13 KiB
351 lines
13 KiB
3 years ago
|
"""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.
|
||
|
|
# changes to tokenize more like Posix shells by Vinay Sajip, July 2016.
|
||
|
|
|
||
|
|
import os
|
||
|
|
import re
|
||
|
|
import sys
|
||
|
|
from collections import deque
|
||
|
|
|
||
|
|
from io import StringIO
|
||
|
|
|
||
|
|
__all__ = ["shlex", "split", "quote", "join"]
|
||
|
|
|
||
|
|
class shlex:
|
||
|
|
"A lexical analyzer class for simple shell-like syntaxes."
|
||
|
|
def __init__(self, instream=None, infile=None, posix=False,
|
||
|
|
punctuation_chars=False):
|
||
|
|
if isinstance(instream, str):
|
||
|
|
instream = StringIO(instream)
|
||
|
|
if instream is not None:
|
||
|
|
self.instream = instream
|
||
|
|
self.infile = infile
|
||
|
|
else:
|
||
|
|
self.instream = sys.stdin
|
||
|
|
self.infile = None
|
||
|
|
self.posix = posix
|
||
|
|
if posix:
|
||
|
|
self.eof = None
|
||
|
|
else:
|
||
|
|
self.eof = ''
|
||
|
|
self.commenters = '#'
|
||
|
|
self.wordchars = ('abcdfeghijklmnopqrstuvwxyz'
|
||
|
|
'ABCDEFGHIJKLMNOPQRSTUVWXYZ0123456789_')
|
||
|
|
if self.posix:
|
||
|
|
self.wordchars += ('ßàáâãäåæçèéêëìíîïðñòóôõöøùúûüýþÿ'
|
||
|
|
'ÀÁÂÃÄÅÆÇÈÉÊËÌÍÎÏÐÑÒÓÔÕÖØÙÚÛÜÝÞ')
|
||
|
|
self.whitespace = ' \t\r\n'
|
||
|
|
self.whitespace_split = False
|
||
|
|
self.quotes = '\'"'
|
||
|
|
self.escape = '\\'
|
||
|
|
self.escapedquotes = '"'
|
||
|
|
self.state = ' '
|
||
|
|
self.pushback = deque()
|
||
|
|
self.lineno = 1
|
||
|
|
self.debug = 0
|
||
|
|
self.token = ''
|
||
|
|
self.filestack = deque()
|
||
|
|
self.source = None
|
||
|
|
if not punctuation_chars:
|
||
|
|
punctuation_chars = ''
|
||
|
|
elif punctuation_chars is True:
|
||
|
|
punctuation_chars = '();<>|&'
|
||
|
|
self._punctuation_chars = punctuation_chars
|
||
|
|
if punctuation_chars:
|
||
|
|
# _pushback_chars is a push back queue used by lookahead logic
|
||
|
|
self._pushback_chars = deque()
|
||
|
|
# these chars added because allowed in file names, args, wildcards
|
||
|
|
self.wordchars += '~-./*?='
|
||
|
|
#remove any punctuation chars from wordchars
|
||
|
|
t = self.wordchars.maketrans(dict.fromkeys(punctuation_chars))
|
||
|
|
self.wordchars = self.wordchars.translate(t)
|
||
|
|
|
||
|
|
@property
|
||
|
|
def punctuation_chars(self):
|
||
|
|
return self._punctuation_chars
|
||
|
|
|
||
|
|
def push_token(self, tok):
|
||
|
|
"Push a token onto the stack popped by the get_token method"
|
||
|
|
if self.debug >= 1:
|
||
|
|
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, str):
|
||
|
|
newstream = StringIO(newstream)
|
||
|
|
self.filestack.appendleft((self.infile, self.instream, self.lineno))
|
||
|
|
self.infile = newfile
|
||
|
|
self.instream = newstream
|
||
|
|
self.lineno = 1
|
||
|
|
if self.debug:
|
||
|
|
if newfile is not None:
|
||
|
|
print('shlex: pushing to file %s' % (self.infile,))
|
||
|
|
else:
|
||
|
|
print('shlex: pushing to stream %s' % (self.instream,))
|
||
|
|
|
||
|
|
def pop_source(self):
|
||
|
|
"Pop the input source stack."
|
||
|
|
self.instream.close()
|
||
|
|
(self.infile, self.instream, self.lineno) = self.filestack.popleft()
|
||
|
|
if self.debug:
|
||
|
|
print('shlex: popping to %s, line %d' \
|
||
|
|
% (self.instream, self.lineno))
|
||
|
|
self.state = ' '
|
||
|
|
|
||
|
|
def get_token(self):
|
||
|
|
"Get a token from the input stream (or from stack if it's nonempty)"
|
||
|
|
if self.pushback:
|
||
|
|
tok = self.pushback.popleft()
|
||
|
|
if self.debug >= 1:
|
||
|
|
print("shlex: popping token " + repr(tok))
|
||
|
|
return tok
|
||
|
|
# No pushback. Get a token.
|
||
|
|
raw = self.read_token()
|
||
|
|
# Handle inclusions
|
||
|
|
if self.source is not None:
|
||
|
|
while raw == self.source:
|
||
|
|
spec = self.sourcehook(self.read_token())
|
||
|
|
if spec:
|
||
|
|
(newfile, newstream) = spec
|
||
|
|
self.push_source(newstream, newfile)
|
||
|
|
raw = self.get_token()
|
||
|
|
# Maybe we got EOF instead?
|
||
|
|
while raw == self.eof:
|
||
|
|
if not self.filestack:
|
||
|
|
return self.eof
|
||
|
|
else:
|
||
|
|
self.pop_source()
|
||
|
|
raw = self.get_token()
|
||
|
|
# Neither inclusion nor EOF
|
||
|
|
if self.debug >= 1:
|
||
|
|
if raw != self.eof:
|
||
|
|
print("shlex: token=" + repr(raw))
|
||
|
|
else:
|
||
|
|
print("shlex: token=EOF")
|
||
|
|
return raw
|
||
|
|
|
||
|
|
def read_token(self):
|
||
|
|
quoted = False
|
||
|
|
escapedstate = ' '
|
||
|
|
while True:
|
||
|
|
if self.punctuation_chars and self._pushback_chars:
|
||
|
|
nextchar = self._pushback_chars.pop()
|
||
|
|
else:
|
||
|
|
nextchar = self.instream.read(1)
|
||
|
|
if nextchar == '\n':
|
||
|
|
self.lineno += 1
|
||
|
|
if self.debug >= 3:
|
||
|
|
print("shlex: in state %r I see character: %r" % (self.state,
|
||
|
|
nextchar))
|
||
|
|
if self.state is None:
|
||
|
|
self.token = '' # past end of file
|
||
|
|
break
|
||
|
|
elif self.state == ' ':
|
||
|
|
if not nextchar:
|
||
|
|
self.state = None # end of file
|
||
|
|
break
|
||
|
|
elif nextchar in self.whitespace:
|
||
|
|
if self.debug >= 2:
|
||
|
|
print("shlex: I see whitespace in whitespace state")
|
||
|
|
if self.token or (self.posix and quoted):
|
||
|
|
break # emit current token
|
||
|
|
else:
|
||
|
|
continue
|
||
|
|
elif nextchar in self.commenters:
|
||
|
|
self.instream.readline()
|
||
|
|
self.lineno += 1
|
||
|
|
elif self.posix and nextchar in self.escape:
|
||
|
|
escapedstate = 'a'
|
||
|
|
self.state = nextchar
|
||
|
|
elif nextchar in self.wordchars:
|
||
|
|
self.token = nextchar
|
||
|
|
self.state = 'a'
|
||
|
|
elif nextchar in self.punctuation_chars:
|
||
|
|
self.token = nextchar
|
||
|
|
self.state = 'c'
|
||
|
|
elif nextchar in self.quotes:
|
||
|
|
if not self.posix:
|
||
|
|
self.token = nextchar
|
||
|
|
self.state = nextchar
|
||
|
|
elif self.whitespace_split:
|
||
|
|
self.token = nextchar
|
||
|
|
self.state = 'a'
|
||
|
|
else:
|
||
|
|
self.token = nextchar
|
||
|
|
if self.token or (self.posix and quoted):
|
||
|
|
break # emit current token
|
||
|
|
else:
|
||
|
|
continue
|
||
|
|
elif self.state in self.quotes:
|
||
|
|
quoted = True
|
||
|
|
if not nextchar: # end of file
|
||
|
|
if self.debug >= 2:
|
||
|
|
print("shlex: I see EOF in quotes state")
|
||
|
|
# XXX what error should be raised here?
|
||
|
|
raise ValueError("No closing quotation")
|
||
|
|
if nextchar == self.state:
|
||
|
|
if not self.posix:
|
||
|
|
self.token += nextchar
|
||
|
|
self.state = ' '
|
||
|
|
break
|
||
|
|
else:
|
||
|
|
self.state = 'a'
|
||
|
|
elif (self.posix and nextchar in self.escape and self.state
|
||
|
|
in self.escapedquotes):
|
||
|
|
escapedstate = self.state
|
||
|
|
self.state = nextchar
|
||
|
|
else:
|
||
|
|
self.token += nextchar
|
||
|
|
elif self.state in self.escape:
|
||
|
|
if not nextchar: # end of file
|
||
|
|
if self.debug >= 2:
|
||
|
|
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.state
|
||
|
|
self.token += nextchar
|
||
|
|
self.state = escapedstate
|
||
|
|
elif self.state in ('a', 'c'):
|
||
|
|
if not nextchar:
|
||
|
|
self.state = None # end of file
|
||
|
|
break
|
||
|
|
elif nextchar in self.whitespace:
|
||
|
|
if self.debug >= 2:
|
||
|
|
print("shlex: I see whitespace in word state")
|
||
|
|
self.state = ' '
|
||
|
|
if self.token or (self.posix and quoted):
|
||
|
|
break # emit current token
|
||
|
|
else:
|
||
|
|
continue
|
||
|
|
elif nextchar in self.commenters:
|
||
|
|
self.instream.readline()
|
||
|
|
self.lineno += 1
|
||
|
|
if self.posix:
|
||
|
|
self.state = ' '
|
||
|
|
if self.token or (self.posix and quoted):
|
||
|
|
break # emit current token
|
||
|
|
else:
|
||
|
|
continue
|
||
|
|
elif self.state == 'c':
|
||
|
|
if nextchar in self.punctuation_chars:
|
||
|
|
self.token += nextchar
|
||
|
|
else:
|
||
|
|
if nextchar not in self.whitespace:
|
||
|
|
self._pushback_chars.append(nextchar)
|
||
|
|
self.state = ' '
|
||
|
|
break
|
||
|
|
elif self.posix and nextchar in self.quotes:
|
||
|
|
self.state = nextchar
|
||
|
|
elif self.posix and nextchar in self.escape:
|
||
|
|
escapedstate = 'a'
|
||
|
|
self.state = nextchar
|
||
|
|
elif (nextchar in self.wordchars or nextchar in self.quotes
|
||
|
|
or (self.whitespace_split and
|
||
|
|
nextchar not in self.punctuation_chars)):
|
||
|
|
self.token += nextchar
|
||
|
|
else:
|
||
|
|
if self.punctuation_chars:
|
||
|
|
self._pushback_chars.append(nextchar)
|
||
|
|
else:
|
||
|
|
self.pushback.appendleft(nextchar)
|
||
|
|
if self.debug >= 2:
|
||
|
|
print("shlex: I see punctuation in word state")
|
||
|
|
self.state = ' '
|
||
|
|
if self.token or (self.posix and quoted):
|
||
|
|
break # emit current token
|
||
|
|
else:
|
||
|
|
continue
|
||
|
|
result = self.token
|
||
|
|
self.token = ''
|
||
|
|
if self.posix and not quoted and result == '':
|
||
|
|
result = None
|
||
|
|
if self.debug > 1:
|
||
|
|
if result:
|
||
|
|
print("shlex: raw token=" + repr(result))
|
||
|
|
else:
|
||
|
|
print("shlex: raw token=EOF")
|
||
|
|
return result
|
||
|
|
|
||
|
|
def sourcehook(self, newfile):
|
||
|
|
"Hook called on a filename to be sourced."
|
||
|
|
if newfile[0] == '"':
|
||
|
|
newfile = newfile[1:-1]
|
||
|
|
# This implements cpp-like semantics for relative-path inclusion.
|
||
|
|
if isinstance(self.infile, str) 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."
|
||
|
|
if infile is None:
|
||
|
|
infile = self.infile
|
||
|
|
if lineno is None:
|
||
|
|
lineno = self.lineno
|
||
|
|
return "\"%s\", line %d: " % (infile, lineno)
|
||
|
|
|
||
|
|
def __iter__(self):
|
||
|
|
return self
|
||
|
|
|
||
|
|
def __next__(self):
|
||
|
|
token = self.get_token()
|
||
|
|
if token == self.eof:
|
||
|
|
raise StopIteration
|
||
|
|
return token
|
||
|
|
|
||
|
|
def split(s, comments=False, posix=True):
|
||
|
|
"""Split the string *s* using shell-like syntax."""
|
||
|
|
if s is None:
|
||
|
|
import warnings
|
||
|
|
warnings.warn("Passing None for 's' to shlex.split() is deprecated.",
|
||
|
|
DeprecationWarning, stacklevel=2)
|
||
|
|
lex = shlex(s, posix=posix)
|
||
|
|
lex.whitespace_split = True
|
||
|
|
if not comments:
|
||
|
|
lex.commenters = ''
|
||
|
|
return list(lex)
|
||
|
|
|
||
|
|
|
||
|
|
def join(split_command):
|
||
|
|
"""Return a shell-escaped string from *split_command*."""
|
||
|
|
return ' '.join(quote(arg) for arg in split_command)
|
||
|
|
|
||
|
|
|
||
|
|
_find_unsafe = re.compile(r'[^\w@%+=:,./-]', re.ASCII).search
|
||
|
|
|
||
|
|
def quote(s):
|
||
|
|
"""Return a shell-escaped version of the string *s*."""
|
||
|
|
if not s:
|
||
|
|
return "''"
|
||
|
|
if _find_unsafe(s) is None:
|
||
|
|
return s
|
||
|
|
|
||
|
|
# use single quotes, and put single quotes into double quotes
|
||
|
|
# the string $'b is then quoted as '$'"'"'b'
|
||
|
|
return "'" + s.replace("'", "'\"'\"'") + "'"
|
||
|
|
|
||
|
|
|
||
|
|
def _print_tokens(lexer):
|
||
|
|
while 1:
|
||
|
|
tt = lexer.get_token()
|
||
|
|
if not tt:
|
||
|
|
break
|
||
|
|
print("Token: " + repr(tt))
|
||
|
|
|
||
|
|
if __name__ == '__main__':
|
||
|
|
if len(sys.argv) == 1:
|
||
|
|
_print_tokens(shlex())
|
||
|
|
else:
|
||
|
|
fn = sys.argv[1]
|
||
|
|
with open(fn) as f:
|
||
|
|
_print_tokens(shlex(f, fn))
|