It no longer makes sense to run this script from the command line.  Doing so
will only print out this usage information.

Usage:

    %(PROGRAM)s [options] <%%S> email-addr [email-addr ...]

Where options are:

    --cvsroot=<path>
    	Use <path> as the environment variable CVSROOT.  Otherwise this
    	variable must exist in the environment.




    --context=#
    -C #
        Include # lines of context around lines that differ (default: 2).

    -c
        Produce a context diff (default).

    -u
        Produce a unified diff (smaller).

    --quiet / -q
        Don't print as much status to stdout.

    --fromhost=hostname
    -f hostname
        The hostname that email messages appear to be coming from.  The From:
        header will of the outgoing message will look like user@hostname.  By
        default, hostname is the machine's fully qualified domain name.

    --help / -h
        Print this text.

The rest of the command line arguments are:

    <%%S>
        CVS %%s loginfo expansion.  When invoked by CVS, this will be a single
        string containing the directory the checkin is being made in, relative
        to $CVSROOT, followed by the list of files that are changing.  If the
        %%s in the loginfo file is %%{sVv}, context diffs for each of the
        modified files are included in any email messages that are generated.

    email-addrs
        At least one email address.
"""
import os
import sys
import re
import time
import string
import getopt
import smtplib
import pwd
import socket

try:
    from socket import getfqdn
except ImportError:
    def getfqdn():
        # Python 1.5.2 :(
        hostname = socket.gethostname()
        byaddr = socket.gethostbyaddr(socket.gethostbyname(hostname))
        aliases = byaddr[1]
        aliases.insert(0, byaddr[0])
        aliases.insert(0, hostname)
        for fqdn in aliases:
            if '.' in fqdn:
                break
        else:
            fqdn = 'localhost.localdomain'
        return fqdn
    

from cStringIO import StringIO

# Which SMTP server to do we connect to?  Empty string means localhost.
MAILHOST = ''
MAILPORT = 25

COMMASPACE = ', '

PROGRAM = sys.argv[0]

BINARY_EXPLANATION_LINES = [
    "(This appears to be a binary file; contents omitted.)\n"
    ]

REVCRE = re.compile("^(NONE|[0-9.]+)$")
NOVERSION = "Couldn't generate diff; no version number found in filespec: %s"
BACKSLASH = "Couldn't generate diff: backslash in filespec's filename: %s"



def usage(code, msg=''):
    print __doc__ % globals()
    if msg:
        print msg
    sys.exit(code)



def calculate_diff(filespec, contextlines):

    file, oldrev, newrev = string.split(filespec, ',')
    # Make sure we can find a CVS version number
    if not REVCRE.match(oldrev):
        return NOVERSION % filespec
    if not REVCRE.match(newrev):
        return NOVERSION % filespec

    if string.find(file, '\\') <> -1:
        # I'm sorry, a file name that contains a backslash is just too much.
        # XXX if someone wants to figure out how to escape the backslashes in
        # a safe way to allow filenames containing backslashes, this is the
        # place to do it.  --Zooko 2002-03-17
        return BACKSLASH % filespec

    if string.find(file, "'") <> -1:
        # Those crazy users put single-quotes in their file names!  Now we
        # have to escape everything that is meaningful inside double-quotes.
        filestr = string.replace(file, '`', '\`')
        filestr = string.replace(filestr, '"', '\"')
        filestr = string.replace(filestr, '$', '\$')
        # and quote it with double-quotes.
        filestr = '"' + filestr + '"'
    else:
        # quote it with single-quotes.
        filestr = "'" + file + "'"
    if oldrev == 'NONE':
        try:
            if os.path.exists(file):
                fp = open(file)
            else:
                update_cmd = "cvs -fn update -r %s -p %s" % (newrev, filestr)
                fp = os.popen(update_cmd)
            lines = fp.readlines()
            fp.close()
            # Is this a binary file?  Let's look at the first few
            # lines to figure it out:
            for line in lines[:5]:
                for c in string.rstrip(line):

    else:
        # This /has/ to happen in the background, otherwise we'll run into CVS
        # lock contention.  What a crock.
        if contextlines > 0:
            difftype = "-C " + str(contextlines)
        else:
            difftype = "-u"
        diffcmd = "/usr/bin/cvs -f diff -kk %s --minimal -r %s -r %s %s" \
                  % (difftype, oldrev, newrev, filestr)
        fp = os.popen(diffcmd)
        lines = fp.readlines()
        sts = fp.close()
        # ignore the error code, it always seems to be 1 :(
##        if sts:
##            return 'Error code %d occurred during diff\n' % (sts >> 8)
    if len(lines) > DIFF_TRUNCATE_IF_LARGER:
        removedlines = len(lines) - DIFF_HEAD_LINES - DIFF_TAIL_LINES
        del lines[DIFF_HEAD_LINES:-DIFF_TAIL_LINES]
        lines.insert(DIFF_HEAD_LINES,
                     '[...%d lines suppressed...]\n' % removedlines)
    return string.join(lines, '')























def blast_mail(subject, people, filestodiff, contextlines, fromhost):
    # cannot wait for child process or that will cause parent to retain cvs
    # lock for too long.  Urg!
    if not os.fork():
        # in the child
        # give up the lock you cvs thang!
        time.sleep(2)
        # Create the smtp connection to the localhost
        conn = smtplib.SMTP()
        conn.connect(MAILHOST, MAILPORT)
        user = pwd.getpwuid(os.getuid())[0]
        domain = fromhost or getfqdn()
        author = '%s@%s' % (user, domain)
        s = StringIO()
        sys.stdout = s
        try:
            print '''\
From: %(author)s
To: %(people)s

        os._exit(0)



# scan args for options
def main():
    try:
        opts, args = getopt.getopt(
            sys.argv[1:], 'hC:cuqf:',
            ['fromhost=', 'context=', 'cvsroot=', 'help', 'quiet'])
    except getopt.error, msg:
        usage(1, msg)

    # parse the options
    contextlines = 2
    verbose = 1
    fromhost = None
    for opt, arg in opts:
        if opt in ('-h', '--help'):
            usage(0)
        elif opt == '--cvsroot':
            os.environ['CVSROOT'] = arg
        elif opt in ('-C', '--context'):
            contextlines = int(arg)
        elif opt == '-c':
            if contextlines <= 0:
                contextlines = 2
        elif opt == '-u':
            contextlines = 0
        elif opt in ('-q', '--quiet'):
            verbose = 0
        elif opt in ('-f', '--fromhost'):
            fromhost = arg

    # What follows is the specification containing the files that were
    # modified.  The argument actually must be split, with the first component
    # containing the directory the checkin is being made in, relative to
    # $CVSROOT, followed by the list of files that are changing.
    if not args:
        usage(1, 'No CVS module specified')

                L[-1] = "%s %s" % (prev, s)
            else:
                L.append(s)
        specs = L

    if verbose:
        print 'Generating notification message...'

    blast_mail(subject, people, specs[1:], contextlines, fromhost)
    if verbose:
        print 'Generating notification message... done.'



if __name__ == '__main__':
    main()
    sys.exit(0)