mirror of
https://github.com/QB64-Phoenix-Edition/QB64pe.git
synced 2024-09-07 10:40:17 +00:00
237 lines
6.8 KiB
Python
237 lines
6.8 KiB
Python
#! /usr/bin/env python
|
|
|
|
"""Conversions to/from quoted-printable transport encoding as per RFC 1521."""
|
|
|
|
# (Dec 1991 version).
|
|
|
|
__all__ = ["encode", "decode", "encodestring", "decodestring"]
|
|
|
|
ESCAPE = '='
|
|
MAXLINESIZE = 76
|
|
HEX = '0123456789ABCDEF'
|
|
EMPTYSTRING = ''
|
|
|
|
try:
|
|
from binascii import a2b_qp, b2a_qp
|
|
except ImportError:
|
|
a2b_qp = None
|
|
b2a_qp = None
|
|
|
|
|
|
def needsquoting(c, quotetabs, header):
|
|
"""Decide whether a particular character needs to be quoted.
|
|
|
|
The 'quotetabs' flag indicates whether embedded tabs and spaces should be
|
|
quoted. Note that line-ending tabs and spaces are always encoded, as per
|
|
RFC 1521.
|
|
"""
|
|
if c in ' \t':
|
|
return quotetabs
|
|
# if header, we have to escape _ because _ is used to escape space
|
|
if c == '_':
|
|
return header
|
|
return c == ESCAPE or not (' ' <= c <= '~')
|
|
|
|
def quote(c):
|
|
"""Quote a single character."""
|
|
i = ord(c)
|
|
return ESCAPE + HEX[i//16] + HEX[i%16]
|
|
|
|
|
|
|
|
def encode(input, output, quotetabs, header = 0):
|
|
"""Read 'input', apply quoted-printable encoding, and write to 'output'.
|
|
|
|
'input' and 'output' are files with readline() and write() methods.
|
|
The 'quotetabs' flag indicates whether embedded tabs and spaces should be
|
|
quoted. Note that line-ending tabs and spaces are always encoded, as per
|
|
RFC 1521.
|
|
The 'header' flag indicates whether we are encoding spaces as _ as per
|
|
RFC 1522.
|
|
"""
|
|
|
|
if b2a_qp is not None:
|
|
data = input.read()
|
|
odata = b2a_qp(data, quotetabs = quotetabs, header = header)
|
|
output.write(odata)
|
|
return
|
|
|
|
def write(s, output=output, lineEnd='\n'):
|
|
# RFC 1521 requires that the line ending in a space or tab must have
|
|
# that trailing character encoded.
|
|
if s and s[-1:] in ' \t':
|
|
output.write(s[:-1] + quote(s[-1]) + lineEnd)
|
|
elif s == '.':
|
|
output.write(quote(s) + lineEnd)
|
|
else:
|
|
output.write(s + lineEnd)
|
|
|
|
prevline = None
|
|
while 1:
|
|
line = input.readline()
|
|
if not line:
|
|
break
|
|
outline = []
|
|
# Strip off any readline induced trailing newline
|
|
stripped = ''
|
|
if line[-1:] == '\n':
|
|
line = line[:-1]
|
|
stripped = '\n'
|
|
# Calculate the un-length-limited encoded line
|
|
for c in line:
|
|
if needsquoting(c, quotetabs, header):
|
|
c = quote(c)
|
|
if header and c == ' ':
|
|
outline.append('_')
|
|
else:
|
|
outline.append(c)
|
|
# First, write out the previous line
|
|
if prevline is not None:
|
|
write(prevline)
|
|
# Now see if we need any soft line breaks because of RFC-imposed
|
|
# length limitations. Then do the thisline->prevline dance.
|
|
thisline = EMPTYSTRING.join(outline)
|
|
while len(thisline) > MAXLINESIZE:
|
|
# Don't forget to include the soft line break `=' sign in the
|
|
# length calculation!
|
|
write(thisline[:MAXLINESIZE-1], lineEnd='=\n')
|
|
thisline = thisline[MAXLINESIZE-1:]
|
|
# Write out the current line
|
|
prevline = thisline
|
|
# Write out the last line, without a trailing newline
|
|
if prevline is not None:
|
|
write(prevline, lineEnd=stripped)
|
|
|
|
def encodestring(s, quotetabs = 0, header = 0):
|
|
if b2a_qp is not None:
|
|
return b2a_qp(s, quotetabs = quotetabs, header = header)
|
|
from cStringIO import StringIO
|
|
infp = StringIO(s)
|
|
outfp = StringIO()
|
|
encode(infp, outfp, quotetabs, header)
|
|
return outfp.getvalue()
|
|
|
|
|
|
|
|
def decode(input, output, header = 0):
|
|
"""Read 'input', apply quoted-printable decoding, and write to 'output'.
|
|
'input' and 'output' are files with readline() and write() methods.
|
|
If 'header' is true, decode underscore as space (per RFC 1522)."""
|
|
|
|
if a2b_qp is not None:
|
|
data = input.read()
|
|
odata = a2b_qp(data, header = header)
|
|
output.write(odata)
|
|
return
|
|
|
|
new = ''
|
|
while 1:
|
|
line = input.readline()
|
|
if not line: break
|
|
i, n = 0, len(line)
|
|
if n > 0 and line[n-1] == '\n':
|
|
partial = 0; n = n-1
|
|
# Strip trailing whitespace
|
|
while n > 0 and line[n-1] in " \t\r":
|
|
n = n-1
|
|
else:
|
|
partial = 1
|
|
while i < n:
|
|
c = line[i]
|
|
if c == '_' and header:
|
|
new = new + ' '; i = i+1
|
|
elif c != ESCAPE:
|
|
new = new + c; i = i+1
|
|
elif i+1 == n and not partial:
|
|
partial = 1; break
|
|
elif i+1 < n and line[i+1] == ESCAPE:
|
|
new = new + ESCAPE; i = i+2
|
|
elif i+2 < n and ishex(line[i+1]) and ishex(line[i+2]):
|
|
new = new + chr(unhex(line[i+1:i+3])); i = i+3
|
|
else: # Bad escape sequence -- leave it in
|
|
new = new + c; i = i+1
|
|
if not partial:
|
|
output.write(new + '\n')
|
|
new = ''
|
|
if new:
|
|
output.write(new)
|
|
|
|
def decodestring(s, header = 0):
|
|
if a2b_qp is not None:
|
|
return a2b_qp(s, header = header)
|
|
from cStringIO import StringIO
|
|
infp = StringIO(s)
|
|
outfp = StringIO()
|
|
decode(infp, outfp, header = header)
|
|
return outfp.getvalue()
|
|
|
|
|
|
|
|
# Other helper functions
|
|
def ishex(c):
|
|
"""Return true if the character 'c' is a hexadecimal digit."""
|
|
return '0' <= c <= '9' or 'a' <= c <= 'f' or 'A' <= c <= 'F'
|
|
|
|
def unhex(s):
|
|
"""Get the integer value of a hexadecimal number."""
|
|
bits = 0
|
|
for c in s:
|
|
if '0' <= c <= '9':
|
|
i = ord('0')
|
|
elif 'a' <= c <= 'f':
|
|
i = ord('a')-10
|
|
elif 'A' <= c <= 'F':
|
|
i = ord('A')-10
|
|
else:
|
|
break
|
|
bits = bits*16 + (ord(c) - i)
|
|
return bits
|
|
|
|
|
|
|
|
def main():
|
|
import sys
|
|
import getopt
|
|
try:
|
|
opts, args = getopt.getopt(sys.argv[1:], 'td')
|
|
except getopt.error, msg:
|
|
sys.stdout = sys.stderr
|
|
print msg
|
|
print "usage: quopri [-t | -d] [file] ..."
|
|
print "-t: quote tabs"
|
|
print "-d: decode; default encode"
|
|
sys.exit(2)
|
|
deco = 0
|
|
tabs = 0
|
|
for o, a in opts:
|
|
if o == '-t': tabs = 1
|
|
if o == '-d': deco = 1
|
|
if tabs and deco:
|
|
sys.stdout = sys.stderr
|
|
print "-t and -d are mutually exclusive"
|
|
sys.exit(2)
|
|
if not args: args = ['-']
|
|
sts = 0
|
|
for file in args:
|
|
if file == '-':
|
|
fp = sys.stdin
|
|
else:
|
|
try:
|
|
fp = open(file)
|
|
except IOError, msg:
|
|
sys.stderr.write("%s: can't open (%s)\n" % (file, msg))
|
|
sts = 1
|
|
continue
|
|
if deco:
|
|
decode(fp, sys.stdout)
|
|
else:
|
|
encode(fp, sys.stdout, tabs)
|
|
if fp is not sys.stdin:
|
|
fp.close()
|
|
if sts:
|
|
sys.exit(sts)
|
|
|
|
|
|
|
|
if __name__ == '__main__':
|
|
main()
|