"""This module co-ordinates the reading of the source file.
It maintains the current position of the parser in the source file.
(c) Copyright by Jay Love, 2000 (mailto:jsliv@jslove.org)
Permission to use, copy, modify, and distribute this software and its
documentation for any purpose and without fee or royalty is hereby granted,
provided that the above copyright notice appear in all copies and that
both that copyright notice and this permission notice appear in
supporting documentation or portions thereof, including modifications,
that you make.
THE AUTHORS DISCLAIM ALL WARRANTIES WITH REGARD TO
THIS SOFTWARE, INCLUDING ALL IMPLIED WARRANTIES OF MERCHANTABILITY AND
FITNESS, IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY SPECIAL,
INDIRECT OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES WHATSOEVER RESULTING
FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN ACTION OF CONTRACT,
NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF OR IN CONNECTION
WITH THE USE OR PERFORMANCE OF THIS SOFTWARE !
This software is based in part on work done by the Jakarta group.
"""
from Context import *
import copy
import os
class Mark:
"""The Mark class marks a point in an input stream."""
def __init__(self, reader, fileid=None, stream=None, inBaseDir=None, encoding=None):
if isinstance(reader, StreamReader):
self.reader = reader
self.fileid = fileid
self.includeStack = []
self.cursor = 0
self.stream = stream
self.baseDir = inBaseDir
self.encoding = encoding
else:
self = copy.copy(reader)
# I think the includeStack will be copied correctly,
# but check here for problems: raise Error('clone include stack')
# JSP has an equals function, but I don't think I need that,
# because of using copy, but maybe I do.
def getFile(self):
return self.reader.getFile(self.fileid)
def __str__(self):
return self.getFile() + '(' + str(self.line) + str(self.col) + ')'
def __repr__(self):
return self.getFile() + '(' + str(self.col) + ')'
def pushStream(self, infileid, inStream, inBaseDir, inEncoding):
self.includeStack.append((self.cursor, self.fileid, self.baseDir, self.encoding, self.stream))
self.cursor = 0
self.fileid = infileid
self.baseDir = inBaseDir
self.encoding = inEncoding
self.stream = inStream
def popStream(self):
if len(self.includeStack) == 0:
return 0 # false
list = self.includeStack[len(self.includeStack)-1]
del self.includeStack[len(self.includeStack)-1]
self.cursor = list[0]
self.fileid = list[1]
self.baseDir = list[2]
self.encoding = list[3]
self.stream = list[4]
return 1 # true
class StreamReader:
"""This class handles the PSP source file.
It provides the characters to the other parts of the system.
It can move forward and backwards in a file and remember locactions.
"""
def __init__(self, filename, ctxt):
self._pspfile = filename
self._ctxt = ctxt
self._filehandle = None
self.sourcefiles = []
self.current = None
self.master = None
def init(self):
self.pushFile(self._ctxt.getFullPspFileName())
def registerSourceFile(self, file):
self.sourcefiles.append(file)
return len(self.sourcefiles) - 1
def pushFile(self, file, encoding=None):
assert type(file) == type('')
# if type(file) != type(''):
# we've got an open file handle - don't think this case exists
# Don't know what this master stuff is, but until I do, implement it.
# Oh, it's the original file.
if self.master is None:
parent = None
self.master = file
else:
parent = os.path.split(self.master)[0]
isAbsolute = os.path.isabs(file)
if parent is not None and not isAbsolute:
file = os.path.join(parent, file)
fileid = self.registerSourceFile(file)
handle = open(file, 'r')
stream = handle.read()
handle.seek(0, 0)
lines = handle.readlines()
z = 0
for i in lines:
lines[z] = i.replace('\r\n', '\n').replace('\r', '\n')
z += 1
stream = ''.join(lines)
if self.current is None:
self.current = Mark(self, fileid, stream,
self._ctxt.getBaseUri(), encoding)
else:
self.current.pushStream(fileid, stream,
self._ctxt.getBaseUri(), encoding) # don't use yet
def popFile(self):
if self.current is None:
return 0
return self.current.popStream()
def getFile(self, i):
return self.sourcefiles[i]
def newSourceFile(self, filename):
if filename in self.sourcefiles:
return None
self.sourcefiles.append(filename)
return len(self.sourcefiles)
def Mark(self):
return copy.copy(self.current)
def skipUntil(self, st):
"""Greedy search.
Return the point before the string, but move reader past it.
"""
pt = self.current.stream.find(st, self.current.cursor)
if pt == -1:
self.current.cursor = len(self.current.stream)
if self.hasMoreInput():
self.popFile() # @@ Should I do this here? 6/1/00
self.skipUntil(st)
else:
raise EOFError
else:
self.current.cursor = pt
ret = self.Mark()
self.current.cursor += len(st)
return ret
def reset(self, mark):
self.current = mark
def Matches(self, st):
if st == self.current.stream[
self.current.cursor:self.current.cursor+len(st)]:
return 1
return 0
def Advance(self, length):
"""Advance length characters"""
if length + self.current.cursor <= len(self.current.stream):
self.current.cursor += length
else:
prog = len(self.current.stream) - self.current.cursor
self.current.cursor = len(self.current.stream)
if self.hasMoreInput():
self.Advance(length-prog)
else:
raise EOFError()
def nextChar(self):
if self.hasMoreInput() == 0:
return -1
ch = self.current.stream[self.current.cursor]
self.Advance(1)
return ch
def isSpace(self):
"""No advancing."""
return self.current.stream[self.current.cursor] == ' ' \
or self.current.stream[self.current.cursor] == '\n'
def isDelimiter(self):
if not self.isSpace():
ch = self.peekChar()
# Look for single character work delimiter:
if ch == '=' or ch == '\"' or ch == "'" or ch == '/':
return 1
# Look for end of comment or basic end tag:
if ch == '-':
mark = self.Mark()
ch = self.nextChar()
ch2 = self.nextChar()
if ch == '>' or (ch == '-' and ch2 == '>'):
self.reset(mark)
return 1
else:
self.reset(mark)
return 0
else:
return 1
def peekChar(self, cnt=1):
if self.hasMoreInput():
return self.current.stream[self.current.cursor:self.current.cursor+cnt]
raise EOFError
def skipSpaces(self):
i = 0
while self.isSpace():
self.nextChar()
i += 1
return i
def getChars(self, start, stop):
oldcurr = self.Mark()
self.reset(start)
chars = self.current.stream[start.cursor:stop.cursor]
self.reset(oldcurr)
return chars
def hasMoreInput(self):
if self.current.cursor >= len(self.current.stream):
while self.popFile():
if self.current.cursor < len(self.current.stream) :
return 1
return 0
return 1
def nextContent(self):
"""Find next < char."""
cur_cursor = self.current.cursor
self.current.cursor += 1
pt = self.current.stream.find('<', self.current.cursor)
if pt == -1:
self.current.cursor = len(self.current.stream)
else:
self.current.cursor = pt
return self.current.stream[cur_cursor:self.current.cursor]
def parseTagAttributes(self):
"""Parse the attributes at the beginning of a tag."""
values = {}
while 1:
self.skipSpaces()
ch = self.peekChar()
if ch == '>':
return values
if ch == '-':
mark = self.Mark()
self.nextChar()
try:
if self.nextChar() == '-' and self.nextChar() == '>':
return values
finally:
self.reset(mark)
elif ch == '%':
mark = self.Mark()
self.nextChar()
try:
ts = self.peekChar()
if ts == '>':
self.reset(mark)
return values
finally:
self.reset(mark)
if ch is None:
break
self.parseAttributeValue(values)
raise ValueError, 'PSP Error - unterminated attribute'
def parseAttributeValue(self, valuedict):
self.skipSpaces()
name = self.parseToken(0)
self.skipSpaces()
if self.peekChar() != '=':
raise ValueError, 'PSP Error - no attribute value'
self.nextChar()
self.skipSpaces()
value = self.parseToken(1)
self.skipSpaces()
valuedict[name] = value
def parseToken(self, quoted):
# This may not be quite right:
buffer = []
self.skipSpaces()
ch = self.peekChar()
if quoted:
if ch == '\"' or ch == "\'":
endquote = ch
ch = self.nextChar()
ch = self.peekChar()
while ch is not None and ch != endquote:
ch = self.nextChar()
if ch == '\\':
ch = self.nextChar()
buffer.append(ch)
ch = self.peekChar()
if ch is None:
raise ValueError, 'PSP Error - unterminated attribute value'
self.nextChar()
else:
if not self.isDelimiter():
while not self.isDelimiter():
ch = self.nextChar()
if ch == '\\':
ch = self.peekChar()
if ch == '\"' or ch == "'" or ch == '>' or ch == '%':
ch = self.nextChar()
buffer.append(ch)
return ''.join(buffer)
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