#!/usr/bin/env python
#
# Script to check for new packages in the incoming directory and process 
# them. 
#
# Checks for .dsc files, verifies all files they reference and complete
# and that their size/md5sum matches. If so they are moved to the build
# directory and a build is spawned for them. 
#
# Care is taken to ensure only one package is built at a time.
#
# This script must be run as the sbuild user
#
# This script is licensed under the GPLv2
#
# Author:	Matt Brown <matt@crc.net.nz>
# Version:  $Id: process_packages 10 2006-06-20 00:56:09Z mglb1 $

import os, os.path, sys
import syslog
import re
import smtplib
import shutil

INCOMING_DIR = "/home/sbuild/incoming"
BUILD_DIR = "/home/sbuild/build"
REPO_BASE_DIR = "/home/httpd/packages.crc.net.nz/repository"
DISTS = [ "crcnet-bpc", "crcnet", "woody" ]

###############################################################################
# FUNCTIONS
##############################################################################
def dscerror(maintainer, basedir, dscfile, error):
    """Generates an error about a DSC file"""

    syslog.syslog(syslog.LOG_NOTICE, "%s. Processing of %s aborted!" % \
        (error, dscfile))

    # Get maintainer email from string
    p = maintainer.split("<")
    if len(p) > 1:
        p2 = p[1].split(">")
        email = p2[0]
    else:
        email = ""

    msg = """From: CRCnet Build Daemon <sbuild>
To: %s
Subject: Invalid DSC File: %s

Hi, 

This is a notification from the CRCnet Build Daemon to tell you that you
have placed an invalid .dsc file in the incoming directory. 

Invalid File:       %s
Error:              %s

This dsc file will not be processed and has been disabled. Please try your
upload again. 

If you have further problems please contact Matt Brown.
""" % (email, dscfile, dscfile, error)

    server = smtplib.SMTP('localhost')
    server.sendmail("sbuild@localhost", ["root@localhost",email], msg)
    server.quit()
 
    # Move the file
    os.rename("%s/%s" % (basedir, dscfile), \
        "%s/%s.invalid" % (basedir, dscfile))
   
def package_added(changedby, package, changes, dist):
    """Generates an install notice for a maintainer"""

    # Get maintainer email from string
    p = changedby.split("<")
    if len(p) > 1:
        p2 = p[1].split(">")
        email = p2[0]
    else:
        email = ""

    msg = """From: CRCnet Archive Daemon <sbuild>
To: %s
Subject: %s ACCEPTED into %s testing archive

%s
""" % (email, package, dist, changes)

    server = smtplib.SMTP('localhost')
    server.sendmail("sbuild@localhost", ["root@localhost",email], msg)
    server.quit()
    
def process_dsc(basedir, filename):
	"""Processes a dsc file"""

	dscfile = open("%s/%s" % (basedir, filename), "r")
	lines = dscfile.readlines()
	mode=1
	files = []
	maintainer = ""
	for line in lines:
		if line.startswith("Maintainer:"):
			maintainer = line
		if line.startswith("Files:"):
			mode=2
			continue
		if mode !=2:
			continue
		# Check for blank line - end of files
		if line.strip() == "":
			break
		# Check for the existance of a file
		parts = line.strip().split(" ")
		fname = "%s/%s" % (basedir, parts[2])
		if not os.path.exists(fname):
			dscerror(maintainer, basedir, filename, \
				"Missing file '%s'" % parts[2])
			return -1
		# Check md5sum
		md5sum = getmd5(fname)
		if md5sum != parts[0]:
			dscerror(maintainer, basedir, filename, \
				"Invalid checksum on '%s'" % parts[2])
			return -1
		# OK
		files.append(parts[2])
	
	# All files are OK
	syslog.syslog(syslog.LOG_NOTICE, "%s accepted for processing" % \
		filename)
	
	move2builddir(basedir, filename, files)
	init_build(filename, dist, files)

	return 0

def getmd5(filename):

	fp = os.popen("/usr/bin/md5sum %s" % filename, "r")
	sum = fp.readline()
	fp.close()
	
	parts = sum.split(" ")
	return parts[0]

def move2builddir(basedir, dscfile, files):
	
	shutil.copy("%s/%s" % (basedir, dscfile), \
			 "%s/%s" % (BUILD_DIR, dscfile))
	os.unlink("%s/%s" % (basedir, dscfile))
	for file in files:
		shutil.copy("%s/%s" % (basedir, file), \
			  "%s/%s" % (BUILD_DIR, file))
		os.unlink("%s/%s" % (basedir, file))
		
def init_build(dscfile, dist, files):

	res = os.fork()
	if res==0:
		# Child
		os.chdir(BUILD_DIR)
		os.execlp("sbuild", "sbuild", "-A", "-s", "--include-source-orig", \
            "-p", "always", "-d", dist, dscfile)
	else:
		# Parent
		fp = open("%s/.buildlock-%s" % (BUILD_DIR, dist), "w")
		fp.write("%s\n" % dscfile)
		fp.write("%d\n" % res)
		fp.close()
		syslog.syslog(syslog.LOG_NOTICE, "Build of %s spawned. " \
			"Pid %d. Distribution %s." % (dscfile, res, dist))
        # Wait for the build to finish
        (pid, rv) = os.waitpid(res, 0)
        if rv != 0:
            syslog.syslog(syslog.LOG_NOTICE, "Build of %s appears to " \
                " have failed. Cleaning up." % dscfile)
            for file in files:
                os.unlink("%s/%s" % (BUILD_DIR, file))
        else:
            syslog.syslog(syslog.LOG_NOTICE, "Build of %s completed " \
                          "successfully." % dscfile)
            add_package(dscfile, dist)
        # Remove the lock
        os.unlink("%s/.buildlock-%s" % (BUILD_DIR, dist))
	
def add_package(dscfile, dist):
    """Inserts a package that has successfully built into the repository"""

    # Calculate what the changes filename should be
    changes = "%s_i386.changes" % dscfile[:-4]
    if not os.path.exists("%s/%s" % (BUILD_DIR, changes)):
        syslog.syslog(syslog.LOG_ERR, "Cannot find changes file (%s) " \
                      "for %s!" % (changes, dscfile))
        return

    # Call reprepro to insert the package into the repository
    fp = os.popen("reprepro -b %s include %s-testing %s/%s 2>&1" % \
        (REPO_BASE_DIR, dist, BUILD_DIR, changes))
    lines = fp.readlines()
    rv = fp.close()
    if rv != None:
        syslog.syslog(syslog.LOG_ERR, "Failed to add %s!" % dscfile)
        syslog.syslog(syslog.LOG_DEBUG, "".join(lines))
        return

    # Added OK, parse changes to get list of files to delete and person 
    # to email
    changesfile = open("%s/%s" % (BUILD_DIR, changes), "r")
    lines = changesfile.readlines()
    changesfile.close()
    mode=1
    changedby = ""
    for line in lines:
        if line.startswith("Changed-By:"):
            changedby = line
        if line.startswith("Files:"):
            mode=2
            continue
        if mode !=2:
            continue
        # Check for blank line - end of files
        if line.strip() == "":
            break
        # Check for the existance of a file
        parts = line.strip().split(" ")
        fname = "%s/%s" % (BUILD_DIR, parts[4])
        os.unlink(fname)
    os.unlink("%s/%s" % (BUILD_DIR, changes))

    # Send email
    parts = dscfile.split("_")
    package_added(changedby, parts[0], "".join(lines), dist)

def is_build_running(dist):
    """Checks if the specified distribution is busy building or not"""

    lockfile = "%s/.buildlock-%s" % (BUILD_DIR, dist)
    # If a build is currently running do nothing
    if os.path.exists(lockfile):
        # Check if the build is still in progress
        fp = open(lockfile, "r")
        lines = fp.readlines()
        if len(lines) != 2:
            syslog.syslog(syslog.LOG_NOTICE, "Invalid lockfile - %s! " \
                "Removing" % dist)
            os.unlink(lockfile)
            return 0
        alive=0
        try:
            os.kill(int(lines[1]), 0)
            alive=1
        except:
            pass
        if alive==1:
            syslog.syslog(syslog.LOG_NOTICE, "Build of %s (%s) still in " \
                "progress. Aborting run" % (lines[0], dist))
            return -1
        else:
            syslog.syslog(syslog.LOG_NOTICE, "Build of %s (%s) appears to " \
                "have completed. Removing lockfile." % (lines[0], dist))
            os.unlink(lockfile)

    return 0

def process_dist(dist):

    incoming_dir = "%s/%s" % (INCOMING_DIR, dist)

    if is_build_running(dist) < 0:
        return
        
    #syslog.syslog(syslog.LOG_NOTICE, "Scanning %s" % incoming_dir)
    
    dscpat = re.compile(".*\\.dsc$")
    
    # Process all files in the incoming directory
    files = os.listdir(incoming_dir)
    c=0
    for file in files:
        # Skip files not matching the .dsc pattern
        m = dscpat.match(file)
        if m == None:
            continue
        # Found a dsc file, process it
        c+=1
        if process_dsc(incoming_dir, file) >= 0:
            break
        
    #syslog.syslog(syslog.LOG_NOTICE, "Run completed for %s. %d dsc files " \
    #    "processed." % (dist, c))
                                        
###############################################################################
# MAINLINE
###############################################################################
# Setup logging
syslog.openlog("process-packages", 0, syslog.LOG_DAEMON)

# Process each distribution in turn
for dist in DISTS:
    process_dist(dist)
    
# vim: ts=4 sts=4 sw=4 et