[Python-checkins] CVS: python/dist/src/Lib FCNTL.py,NONE,1.1.4.1 HTMLParser.py,NONE,1.3.4.1
Tim Peters
tim_one@users.sourceforge.net
2001年7月06日 14:06:56 -0700
Update of /cvsroot/python/python/dist/src/Lib
In directory usw-pr-cvs1:/tmp/cvs-serv3927
Added Files:
Tag: descr-branch
FCNTL.py HTMLParser.py
Log Message:
More new additions for descr-branch.
--- NEW FILE: FCNTL.py ---
"""Backward-compatibility version of FCNTL; export constants exported by
fcntl, and issue a deprecation warning.
"""
import warnings
warnings.warn("the FCNTL module is deprecated; please use fcntl",
DeprecationWarning)
# Export the constants known to the fcntl module:
from fcntl import *
# and *only* the constants:
__all__ = [s for s in dir() if s[0] in "ABCDEFGHIJKLMNOPQRSTUVWXYZ"]
--- NEW FILE: HTMLParser.py ---
"""A parser for HTML."""
# This file is based on sgmllib.py, but the API is slightly different.
# XXX There should be a way to distinguish between PCDATA (parsed
# character data -- the normal case), RCDATA (replaceable character
# data -- only char and entity references and end tags are special)
# and CDATA (character data -- only end tags are special).
import re
import string
# Regular expressions used for parsing
interesting_normal = re.compile('[&<]')
interesting_cdata = re.compile(r'<(/|\Z)')
incomplete = re.compile('&([a-zA-Z][-.a-zA-Z0-9]*|#[0-9]*)?')
entityref = re.compile('&([a-zA-Z][-.a-zA-Z0-9]*)[^a-zA-Z0-9]')
charref = re.compile('&#([0-9]+)[^0-9]')
starttagopen = re.compile('<[a-zA-Z]')
piopen = re.compile(r'<\?')
piclose = re.compile('>')
endtagopen = re.compile('</')
declopen = re.compile('<!')
special = re.compile('<![^<>]*>')
commentopen = re.compile('<!--')
commentclose = re.compile(r'--\s*>')
tagfind = re.compile('[a-zA-Z][-.a-zA-Z0-9:_]*')
attrfind = re.compile(
r'\s*([a-zA-Z_][-.:a-zA-Z_0-9]*)(\s*=\s*'
r'(\'[^\']*\'|"[^"]*"|[-a-zA-Z0-9./:;+*%?!&$\(\)_#=~]*))?')
locatestarttagend = re.compile(r"""
<[a-zA-Z][-.a-zA-Z0-9:_]* # tag name
(?:\s+ # whitespace before attribute name
(?:[a-zA-Z_][-.:a-zA-Z0-9_]* # attribute name
(?:\s*=\s* # value indicator
(?:'[^']*' # LITA-enclosed value
|\"[^\"]*\" # LIT-enclosed value
|[^'\">\s]+ # bare value
)
)?
)
)*
\s* # trailing whitespace
""", re.VERBOSE)
endstarttag = re.compile(r"\s*/?>")
endendtag = re.compile('>')
endtagfind = re.compile('</\s*([a-zA-Z][-.a-zA-Z0-9:_]*)\s*>')
declname = re.compile(r'[a-zA-Z][-_.a-zA-Z0-9]*\s*')
declstringlit = re.compile(r'(\'[^\']*\'|"[^"]*")\s*')
class HTMLParseError(Exception):
"""Exception raised for all parse errors."""
def __init__(self, msg, position=(None, None)):
assert msg
self.msg = msg
self.lineno = position[0]
self.offset = position[1]
def __str__(self):
result = self.msg
if self.lineno is not None:
result = result + ", at line %d" % self.lineno
if self.offset is not None:
result = result + ", column %d" % (self.offset + 1)
return result
# HTML parser class -- find tags and call handler functions.
# Usage:
#
# p = HTMLParser(); p.feed(data); ...; p.close()
# Start tags are handled by calling self.handle_starttag() or
# self.handle_startendtag(); end tags by self.handle_endtag(). The
# data between tags is passed from the parser to the derived class by
# calling self.handle_data() with the data as argument (the data may
# be split up in arbitrary chunks). Entity references are passed by
# calling self.handle_entityref() with the entity reference as the
# argument. Numeric character references are passed to
# self.handle_charref() with the string containing the reference as
# the argument.
class HTMLParser:
CDATA_CONTENT_ELEMENTS = ("script", "style")
# Interface -- initialize and reset this instance
def __init__(self):
self.reset()
# Interface -- reset this instance. Loses all unprocessed data
def reset(self):
self.rawdata = ''
self.stack = []
self.lasttag = '???'
self.lineno = 1
self.offset = 0
self.interesting = interesting_normal
# Interface -- feed some data to the parser. Call this as
# often as you want, with as little or as much text as you
# want (may include '\n'). (This just saves the text, all the
# processing is done by goahead().)
def feed(self, data):
self.rawdata = self.rawdata + data
self.goahead(0)
# Interface -- handle the remaining data
def close(self):
self.goahead(1)
# Internal -- update line number and offset. This should be
# called for each piece of data exactly once, in order -- in other
# words the concatenation of all the input strings to this
# function should be exactly the entire input.
def updatepos(self, i, j):
if i >= j:
return j
rawdata = self.rawdata
nlines = string.count(rawdata, "\n", i, j)
if nlines:
self.lineno = self.lineno + nlines
pos = string.rindex(rawdata, "\n", i, j) # Should not fail
self.offset = j-(pos+1)
else:
self.offset = self.offset + j-i
return j
# Interface -- return current line number and offset.
def getpos(self):
return self.lineno, self.offset
__starttag_text = None
# Interface -- return full source of start tag: "<...>"
def get_starttag_text(self):
return self.__starttag_text
def set_cdata_mode(self):
self.interesting = interesting_cdata
def clear_cdata_mode(self):
self.interesting = interesting_normal
# Internal -- handle data as far as reasonable. May leave state
# and data to be processed by a subsequent call. If 'end' is
# true, force handling all data as if followed by EOF marker.
def goahead(self, end):
rawdata = self.rawdata
i = 0
n = len(rawdata)
while i < n:
match = self.interesting.search(rawdata, i) # < or &
if match:
j = match.start()
else:
j = n
if i < j: self.handle_data(rawdata[i:j])
i = self.updatepos(i, j)
if i == n: break
if rawdata[i] == '<':
if starttagopen.match(rawdata, i): # < + letter
k = self.parse_starttag(i)
elif endtagopen.match(rawdata, i): # </
k = self.parse_endtag(i)
if k >= 0:
self.clear_cdata_mode()
elif commentopen.match(rawdata, i): # <!--
k = self.parse_comment(i)
elif piopen.match(rawdata, i): # <?
k = self.parse_pi(i)
elif declopen.match(rawdata, i): # <!
k = self.parse_declaration(i)
else:
if i < n-1:
raise HTMLParseError(
"invalid '<' construct: %s" % `rawdata[i:i+2]`,
self.getpos())
k = -1
if k < 0:
if end:
raise HTMLParseError("EOF in middle of construct",
self.getpos())
break
i = self.updatepos(i, k)
elif rawdata[i] == '&':
match = charref.match(rawdata, i)
if match:
name = match.group(1)
self.handle_charref(name)
k = match.end()
if rawdata[k-1] != ';':
k = k-1
i = self.updatepos(i, k)
continue
match = entityref.match(rawdata, i)
if match:
name = match.group(1)
self.handle_entityref(name)
k = match.end()
if rawdata[k-1] != ';':
k = k-1
i = self.updatepos(i, k)
continue
if incomplete.match(rawdata, i):
if end:
raise HTMLParseError(
"EOF in middle of entity or char ref",
self.getpos())
return -1 # incomplete
raise HTMLParseError("'&' not part of entity or char ref",
self.getpos())
else:
assert 0, "interesting.search() lied"
# end while
if end and i < n:
self.handle_data(rawdata[i:n])
i = self.updatepos(i, n)
self.rawdata = rawdata[i:]
# Internal -- parse comment, return end or -1 if not terminated
def parse_comment(self, i):
rawdata = self.rawdata
assert rawdata[i:i+4] == '<!--', 'unexpected call to parse_comment()'
match = commentclose.search(rawdata, i+4)
if not match:
return -1
j = match.start()
self.handle_comment(rawdata[i+4: j])
j = match.end()
return j
# Internal -- parse declaration.
def parse_declaration(self, i):
# This is some sort of declaration; in "HTML as
# deployed," this should only be the document type
# declaration ("<!DOCTYPE html...>").
rawdata = self.rawdata
j = i + 2
assert rawdata[i:j] == "<!", "unexpected call to parse_declaration"
if rawdata[j:j+1] in ("-", ""):
# Start of comment followed by buffer boundary,
# or just a buffer boundary.
return -1
# in practice, this should look like: ((name|stringlit) S*)+ '>'
n = len(rawdata)
while j < n:
c = rawdata[j]
if c == ">":
# end of declaration syntax
self.handle_decl(rawdata[i+2:j])
return j + 1
if c in "\"'":
m = declstringlit.match(rawdata, j)
if not m:
return -1 # incomplete
j = m.end()
elif c in "abcdefghijklmnopqrstuvwxyzABCDEFGHIJKLMNOPQRSTUVWXYZ":
m = declname.match(rawdata, j)
if not m:
return -1 # incomplete
j = m.end()
else:
raise HTMLParseError(
"unexpected char in declaration: %s" % `rawdata[j]`,
self.getpos())
return -1 # incomplete
# Internal -- parse processing instr, return end or -1 if not terminated
def parse_pi(self, i):
rawdata = self.rawdata
assert rawdata[i:i+2] == '<?', 'unexpected call to parse_pi()'
match = piclose.search(rawdata, i+2) # >
if not match:
return -1
j = match.start()
self.handle_pi(rawdata[i+2: j])
j = match.end()
return j
# Internal -- handle starttag, return end or -1 if not terminated
def parse_starttag(self, i):
self.__starttag_text = None
endpos = self.check_for_whole_start_tag(i)
if endpos < 0:
return endpos
rawdata = self.rawdata
self.__starttag_text = rawdata[i:endpos]
# Now parse the data between i+1 and j into a tag and attrs
attrs = []
match = tagfind.match(rawdata, i+1)
assert match, 'unexpected call to parse_starttag()'
k = match.end()
self.lasttag = tag = string.lower(rawdata[i+1:k])
while k < endpos:
m = attrfind.match(rawdata, k)
if not m:
break
attrname, rest, attrvalue = m.group(1, 2, 3)
if not rest:
attrvalue = None
elif attrvalue[:1] == '\'' == attrvalue[-1:] or \
attrvalue[:1] == '"' == attrvalue[-1:]:
attrvalue = attrvalue[1:-1]
attrvalue = self.unescape(attrvalue)
attrs.append((string.lower(attrname), attrvalue))
k = m.end()
end = string.strip(rawdata[k:endpos])
if end not in (">", "/>"):
lineno, offset = self.getpos()
if "\n" in self.__starttag_text:
lineno = lineno + string.count(self.__starttag_text, "\n")
offset = len(self.__starttag_text) \
- string.rfind(self.__starttag_text, "\n")
else:
offset = offset + len(self.__starttag_text)
raise HTMLParseError("junk characters in start tag: %s"
% `rawdata[k:endpos][:20]`,
(lineno, offset))
if end[-2:] == '/>':
# XHTML-style empty tag: <span attr="value" />
self.handle_startendtag(tag, attrs)
else:
self.handle_starttag(tag, attrs)
if tag in self.CDATA_CONTENT_ELEMENTS:
self.set_cdata_mode()
return endpos
# Internal -- check to see if we have a complete starttag; return end
# or -1 if incomplete.
def check_for_whole_start_tag(self, i):
rawdata = self.rawdata
m = locatestarttagend.match(rawdata, i)
if m:
j = m.end()
next = rawdata[j:j+1]
if next == ">":
return j + 1
if next == "/":
s = rawdata[j:j+2]
if s == "/>":
return j + 2
if s == "/":
# buffer boundary
return -1
# else bogus input
self.updatepos(i, j + 1)
raise HTMLParseError("malformed empty start tag",
self.getpos())
if next == "":
# end of input
return -1
if next in ("abcdefghijklmnopqrstuvwxyz=/"
"ABCDEFGHIJKLMNOPQRSTUVWXYZ"):
# end of input in or before attribute value, or we have the
# '/' from a '/>' ending
return -1
self.updatepos(i, j)
raise HTMLParseError("malformed start tag", self.getpos())
raise AssertionError("we should not gt here!")
# Internal -- parse endtag, return end or -1 if incomplete
def parse_endtag(self, i):
rawdata = self.rawdata
assert rawdata[i:i+2] == "</", "unexpected call to parse_endtag"
match = endendtag.search(rawdata, i+1) # >
if not match:
return -1
j = match.end()
match = endtagfind.match(rawdata, i) # </ + tag + >
if not match:
raise HTMLParseError("bad end tag: %s" % `rawdata[i:j]`,
self.getpos())
tag = match.group(1)
self.handle_endtag(string.lower(tag))
return j
# Overridable -- finish processing of start+end tag: <tag.../>
def handle_startendtag(self, tag, attrs):
self.handle_starttag(tag, attrs)
self.handle_endtag(tag)
# Overridable -- handle start tag
def handle_starttag(self, tag, attrs):
pass
# Overridable -- handle end tag
def handle_endtag(self, tag):
pass
# Overridable -- handle character reference
def handle_charref(self, name):
pass
# Overridable -- handle entity reference
def handle_entityref(self, name):
pass
# Overridable -- handle data
def handle_data(self, data):
pass
# Overridable -- handle comment
def handle_comment(self, data):
pass
# Overridable -- handle declaration
def handle_decl(self, decl):
pass
# Overridable -- handle processing instruction
def handle_pi(self, data):
pass
# Internal -- helper to remove special character quoting
def unescape(self, s):
if '&' not in s:
return s
s = string.replace(s, "<", "<")
s = string.replace(s, ">", ">")
s = string.replace(s, "'", "'")
s = string.replace(s, """, '"')
s = string.replace(s, "&", "&") # Must be last
return s