view contrib/debugcmdserver.py @ 40757:2f14d1bbc9a7

match: remove obsolete catching of OverflowError

Since 0f6a1bdf89fb (match: handle large regexes, 2007-08-19), we catch
an OverflowError from the regex engine and split up the regex if that
happens. In 59a9dc9562e2 (ignore: split up huge patterns, 2008-02-11),
that was extended to raise an OverflowError in our code even if the
regex engine doesn't raise it. It's unclear if there was a range of
regex sizes where the OverflowError would be raised from the regex
engine but that were still below the limit we added in our
code. Either way, both limitations were probably removed in Python
2.7.4 when the regex code width was extended from 16bit to 32bit (or
Py_UCS4) integer (thanks to Yuya for finding that out).

If at least the first limitation was removed, we no longer should be
using OverflowError for flow control, so this patch changes that.

Differential Revision: https://phab.mercurial-scm.org/D5309

#!/usr/bin/env python
#
# Dumps output generated by Mercurial's command server in a formatted style to a
# given file or stderr if '-' is specified. Output is also written in its raw
# format to stdout.
#
# $ ./hg serve --cmds pipe | ./contrib/debugcmdserver.py -
# o, 52   -> 'capabilities: getencoding runcommand\nencoding: UTF-8'

from __future__ import absolute_import, print_function
import struct
import sys

if len(sys.argv) != 2:
    print('usage: debugcmdserver.py FILE')
    sys.exit(1)

outputfmt = '>cI'
outputfmtsize = struct.calcsize(outputfmt)

if sys.argv[1] == '-':
    log = sys.stderr
else:
    log = open(sys.argv[1], 'a')

def read(size):
    data = sys.stdin.read(size)
    if not data:
        raise EOFError
    sys.stdout.write(data)
    sys.stdout.flush()
    return data

try:
    while True:
        header = read(outputfmtsize)
        channel, length = struct.unpack(outputfmt, header)
        log.write('%s, %-4d' % (channel, length))
        if channel in 'IL':
            log.write(' -> waiting for input\n')
        else:
            data = read(length)
            log.write(' -> %r\n' % data)
        log.flush()
except EOFError:
    pass
finally:
    if log != sys.stderr:
        log.close()