#! /usr/bin/env python3
# Written by Martin v. Löwis <loewis@informatik.hu-berlin.de>
"""Generate binary message catalog from textual translation description.
This program converts a textual Uniforum-style message catalog (.po file) into
a binary GNU catalog (.mo file). This is essentially the same function as the
GNU msgfmt program, however, it is a simpler implementation.
Usage: msgfmt.py [OPTIONS] filename.po
Options:
-o file
--output-file=file
Specify the output file to write to. If omitted, output will go to a
file named filename.mo (based off the input file name).
-h
--help
Print this message and exit.
-V
--version
Display version information and exit.
"""
import os
import sys
import ast
import getopt
import struct
import array
from email.parser import HeaderParser
__version__ = "1.1"
MESSAGES = {}
def usage(code, msg=''):
print(__doc__, file=sys.stderr)
if msg:
print(msg, file=sys.stderr)
sys.exit(code)
def add(id, str, fuzzy):
"Add a non-fuzzy translation to the dictionary."
global MESSAGES
if not fuzzy and str:
MESSAGES[id] = str
def generate():
"Return the generated output."
global MESSAGES
# the keys are sorted in the .mo file
keys = sorted(MESSAGES.keys())
offsets = []
ids = strs = b''
for id in keys:
# For each string, we need size and file offset. Each string is NUL
# terminated; the NUL does not count into the size.
offsets.append((len(ids), len(id), len(strs), len(MESSAGES[id])))
ids += id + b'\0'
strs += MESSAGES[id] + b'\0'
output = ''
# The header is 7 32-bit unsigned integers. We don't use hash tables, so
# the keys start right after the index tables.
# translated string.
keystart = 7*4+16*len(keys)
# and the values start after the keys
valuestart = keystart + len(ids)
koffsets = []
voffsets = []
# The string table first has the list of keys, then the list of values.
# Each entry has first the size of the string, then the file offset.
for o1, l1, o2, l2 in offsets:
koffsets += [l1, o1+keystart]
voffsets += [l2, o2+valuestart]
offsets = koffsets + voffsets
output = struct.pack("Iiiiiii",
0x950412de, # Magic
0, # Version
len(keys), # # of entries
7*4, # start of key index
7*4+len(keys)*8, # start of value index
0, 0) # size and offset of hash table
output += array.array("i", offsets).tostring()
output += ids
output += strs
return output
def make(filename, outfile):
ID = 1
STR = 2
# Compute .mo name from .po name and arguments
if filename.endswith('.po'):
infile = filename
else:
infile = filename + '.po'
if outfile is None:
outfile = os.path.splitext(infile)[0] + '.mo'
try:
lines = open(infile, 'rb').readlines()
except IOError as msg:
print(msg, file=sys.stderr)
sys.exit(1)
section = None
fuzzy = 0
# Start off assuming Latin-1, so everything decodes without failure,
# until we know the exact encoding
encoding = 'latin-1'
# Parse the catalog
lno = 0
for l in lines:
l = l.decode(encoding)
lno += 1
# If we get a comment line after a msgstr, this is a new entry
if l[0] == '#' and section == STR:
add(msgid, msgstr, fuzzy)
section = None
fuzzy = 0
# Record a fuzzy mark
if l[:2] == '#,' and 'fuzzy' in l:
fuzzy = 1
# Skip comments
if l[0] == '#':
continue
# Now we are in a msgid section, output previous section
if l.startswith('msgid') and not l.startswith('msgid_plural'):
if section == STR:
add(msgid, msgstr, fuzzy)
if not msgid:
# See whether there is an encoding declaration
p = HeaderParser()
charset = p.parsestr(msgstr.decode(encoding)).get_content_charset()
if charset:
encoding = charset
section = ID
l = l[5:]
msgid = msgstr = b''
is_plural = False
# This is a message with plural forms
elif l.startswith('msgid_plural'):
if section != ID:
print('msgid_plural not preceded by msgid on %s:%d' % (infile, lno),
file=sys.stderr)
sys.exit(1)
l = l[12:]
msgid += b'\0' # separator of singular and plural
is_plural = True
# Now we are in a msgstr section
elif l.startswith('msgstr'):
section = STR
if l.startswith('msgstr['):
if not is_plural:
print('plural without msgid_plural on %s:%d' % (infile, lno),
file=sys.stderr)
sys.exit(1)
l = l.split(']', 1)[1]
if msgstr:
msgstr += b'\0' # Separator of the various plural forms
else:
if is_plural:
print('indexed msgstr required for plural on %s:%d' % (infile, lno),
file=sys.stderr)
sys.exit(1)
l = l[6:]
# Skip empty lines
l = l.strip()
if not l:
continue
l = ast.literal_eval(l)
if section == ID:
msgid += l.encode(encoding)
elif section == STR:
msgstr += l.encode(encoding)
else:
print('Syntax error on %s:%d' % (infile, lno), \
'before:', file=sys.stderr)
print(l, file=sys.stderr)
sys.exit(1)
# Add last entry
if section == STR:
add(msgid, msgstr, fuzzy)
# Compute output
output = generate()
try:
open(outfile,"wb").write(output)
except IOError as msg:
print(msg, file=sys.stderr)
def main():
try:
opts, args = getopt.getopt(sys.argv[1:], 'hVo:',
['help', 'version', 'output-file='])
except getopt.error as msg:
usage(1, msg)
outfile = None
# parse options
for opt, arg in opts:
if opt in ('-h', '--help'):
usage(0)
elif opt in ('-V', '--version'):
print("msgfmt.py", __version__)
sys.exit(0)
elif opt in ('-o', '--output-file'):
outfile = arg
# do it
if not args:
print('No input file given', file=sys.stderr)
print("Try `msgfmt --help' for more information.", file=sys.stderr)
return
for filename in args:
make(filename, outfile)
if __name__ == '__main__':
main()