#!/usr/bin/env python

import os
import sys
import warnings
sys.path.insert(0, os.path.join(os.path.dirname(os.path.dirname(sys.argv[0])), 'lib'))
from bb import fetch2
import logging
import bb
import select
import errno
import signal

# Users shouldn't be running this code directly
if len(sys.argv) != 2 or sys.argv[1] != "decafbad":
    print("bitbake-worker is meant for internal execution by bitbake itself, please don't use it standalone.")
    sys.exit(1)

logger = logging.getLogger("BitBake")

try:
    import cPickle as pickle
except ImportError:
    import pickle
    bb.msg.note(1, bb.msg.domain.Cache, "Importing cPickle failed. Falling back to a very slow implementation.")


worker_pipe = sys.stdout.fileno()
bb.utils.nonblockingfd(worker_pipe)

handler = bb.event.LogHandler()
logger.addHandler(handler)

if 0:
    # Code to write out a log file of all events passing through the worker
    logfilename = "/tmp/workerlogfile"
    format_str = "%(levelname)s: %(message)s"
    conlogformat = bb.msg.BBLogFormatter(format_str)
    consolelog = logging.FileHandler(logfilename)
    bb.msg.addDefaultlogFilter(consolelog)
    consolelog.setFormatter(conlogformat)
    logger.addHandler(consolelog)

worker_queue = ""

def worker_fire(event, d):
    data = "<event>" + pickle.dumps(event) + "</event>"
    worker_fire_prepickled(data)

def worker_fire_prepickled(event):
    global worker_queue

    worker_queue = worker_queue + event
    worker_flush()

def worker_flush():
    global worker_queue, worker_pipe

    if not worker_queue:
        return

    try:
        written = os.write(worker_pipe, worker_queue)
        worker_queue = worker_queue[written:]
    except (IOError, OSError) as e:
        if e.errno != errno.EAGAIN:
            raise

def worker_child_fire(event, d):
    global worker_pipe

    data = "<event>" + pickle.dumps(event) + "</event>"
    worker_pipe.write(data)

bb.event.worker_fire = worker_fire

lf = None
#lf = open("/tmp/workercommandlog", "w+")
def workerlog_write(msg):
    if lf:
        lf.write(msg)
        lf.flush()

def fork_off_task(cfg, data, workerdata, fn, task, taskname, appends, taskdepdata, quieterrors=False):
    # We need to setup the environment BEFORE the fork, since
    # a fork() or exec*() activates PSEUDO...

    envbackup = {}
    fakeenv = {}
    umask = None

    taskdep = workerdata["taskdeps"][fn]
    if 'umask' in taskdep and taskname in taskdep['umask']:
        # umask might come in as a number or text string..
        try:
             umask = int(taskdep['umask'][taskname],8)
        except TypeError:
             umask = taskdep['umask'][taskname]

    # We can't use the fakeroot environment in a dry run as it possibly hasn't been built
    if 'fakeroot' in taskdep and taskname in taskdep['fakeroot'] and not cfg.dry_run:
        envvars = (workerdata["fakerootenv"][fn] or "").split()
        for key, value in (var.split('=') for var in envvars):
            envbackup[key] = os.environ.get(key)
            os.environ[key] = value
            fakeenv[key] = value

        fakedirs = (workerdata["fakerootdirs"][fn] or "").split()
        for p in fakedirs:
            bb.utils.mkdirhier(p)
        logger.debug(2, 'Running %s:%s under fakeroot, fakedirs: %s' %
                        (fn, taskname, ', '.join(fakedirs)))
    else:
        envvars = (workerdata["fakerootnoenv"][fn] or "").split()
        for key, value in (var.split('=') for var in envvars):
            envbackup[key] = os.environ.get(key)
            os.environ[key] = value
            fakeenv[key] = value

    sys.stdout.flush()
    sys.stderr.flush()

    try:
        pipein, pipeout = os.pipe()
        pipein = os.fdopen(pipein, 'rb', 4096)
        pipeout = os.fdopen(pipeout, 'wb', 0)
        pid = os.fork()
    except OSError as e:
        bb.msg.fatal("RunQueue", "fork failed: %d (%s)" % (e.errno, e.strerror))

    if pid == 0:
            global worker_pipe
            pipein.close()

            # Save out the PID so that the event can include it the
            # events
            bb.event.worker_pid = os.getpid()
            bb.event.worker_fire = worker_child_fire
            worker_pipe = pipeout

            # Make the child the process group leader
            os.setpgid(0, 0)
            # No stdin
            newsi = os.open(os.devnull, os.O_RDWR)
            os.dup2(newsi, sys.stdin.fileno())

            if umask:
                os.umask(umask)

            data.setVar("BB_WORKERCONTEXT", "1")
            data.setVar("BB_TASKDEPDATA", taskdepdata)
            data.setVar("BUILDNAME", workerdata["buildname"])
            data.setVar("DATE", workerdata["date"])
            data.setVar("TIME", workerdata["time"])
            bb.parse.siggen.set_taskdata(workerdata["hashes"], workerdata["hash_deps"], workerdata["sigchecksums"])
            ret = 0
            try:
                the_data = bb.cache.Cache.loadDataFull(fn, appends, data)
                the_data.setVar('BB_TASKHASH', workerdata["runq_hash"][task])
                for h in workerdata["hashes"]:
                    the_data.setVar("BBHASH_%s" % h, workerdata["hashes"][h])
                for h in workerdata["hash_deps"]:
                    the_data.setVar("BBHASHDEPS_%s" % h, workerdata["hash_deps"][h])

                # exported_vars() returns a generator which *cannot* be passed to os.environ.update() 
                # successfully. We also need to unset anything from the environment which shouldn't be there 
                exports = bb.data.exported_vars(the_data)
                bb.utils.empty_environment()
                for e, v in exports:
                    os.environ[e] = v
                for e in fakeenv:
                    os.environ[e] = fakeenv[e]
                    the_data.setVar(e, fakeenv[e])
                    the_data.setVarFlag(e, 'export', "1")

                if quieterrors:
                    the_data.setVarFlag(taskname, "quieterrors", "1")

            except Exception as exc:
                if not quieterrors:
                    logger.critical(str(exc))
                os._exit(1)
            try:
                if not cfg.dry_run:
                    ret = bb.build.exec_task(fn, taskname, the_data, cfg.profile)
                os._exit(ret)
            except:
                os._exit(1)
    else:
        for key, value in envbackup.iteritems():
            if value is None:
                del os.environ[key]
            else:
                os.environ[key] = value

    return pid, pipein, pipeout

class runQueueWorkerPipe():
    """
    Abstraction for a pipe between a worker thread and the worker server
    """
    def __init__(self, pipein, pipeout):
        self.input = pipein
        if pipeout:
            pipeout.close()
        bb.utils.nonblockingfd(self.input)
        self.queue = ""

    def read(self):
        start = len(self.queue)
        try:
            self.queue = self.queue + self.input.read(102400)
        except (OSError, IOError) as e:
            if e.errno != errno.EAGAIN:
                raise

        end = len(self.queue)
        index = self.queue.find("</event>")
        while index != -1:
            worker_fire_prepickled(self.queue[:index+8])
            self.queue = self.queue[index+8:]
            index = self.queue.find("</event>")
        return (end > start)

    def close(self):
        while self.read():
            continue
        if len(self.queue) > 0:
            print("Warning, worker child left partial message: %s" % self.queue)
        self.input.close()

normalexit = False

class BitbakeWorker(object):
    def __init__(self, din):
        self.input = din
        bb.utils.nonblockingfd(self.input)
        self.queue = ""
        self.cookercfg = None
        self.databuilder = None
        self.data = None
        self.build_pids = {}
        self.build_pipes = {}
    
    def serve(self):        
        while True:
            (ready, _, _) = select.select([self.input] + [i.input for i in self.build_pipes.values()], [] , [], 1)
            if self.input in ready or len(self.queue):
                start = len(self.queue)
                try:
                    self.queue = self.queue + self.input.read()
                except (OSError, IOError):
                    pass
                end = len(self.queue)
                self.handle_item("cookerconfig", self.handle_cookercfg)
                self.handle_item("workerdata", self.handle_workerdata)
                self.handle_item("runtask", self.handle_runtask)
                self.handle_item("finishnow", self.handle_finishnow)
                self.handle_item("ping", self.handle_ping)
                self.handle_item("quit", self.handle_quit)

            for pipe in self.build_pipes:
                self.build_pipes[pipe].read()
            if len(self.build_pids):
                self.process_waitpid()
            worker_flush()


    def handle_item(self, item, func):
        if self.queue.startswith("<" + item + ">"):
            index = self.queue.find("</" + item + ">")
            while index != -1:
                func(self.queue[(len(item) + 2):index])
                self.queue = self.queue[(index + len(item) + 3):]
                index = self.queue.find("</" + item + ">")

    def handle_cookercfg(self, data):
        self.cookercfg = pickle.loads(data)
        self.databuilder = bb.cookerdata.CookerDataBuilder(self.cookercfg, worker=True)
        self.databuilder.parseBaseConfiguration()
        self.data = self.databuilder.data

    def handle_workerdata(self, data):
        self.workerdata = pickle.loads(data)
        bb.msg.loggerDefaultDebugLevel = self.workerdata["logdefaultdebug"]
        bb.msg.loggerDefaultVerbose = self.workerdata["logdefaultverbose"]
        bb.msg.loggerVerboseLogs = self.workerdata["logdefaultverboselogs"]
        bb.msg.loggerDefaultDomains = self.workerdata["logdefaultdomain"]
        self.data.setVar("PRSERV_HOST", self.workerdata["prhost"])

    def handle_ping(self, _):
        workerlog_write("Handling ping\n")

        logger.warn("Pong from bitbake-worker!")

    def handle_quit(self, data):
        workerlog_write("Handling quit\n")

        global normalexit
        normalexit = True
        sys.exit(0)

    def handle_runtask(self, data):
        fn, task, taskname, quieterrors, appends, taskdepdata = pickle.loads(data)
        workerlog_write("Handling runtask %s %s %s\n" % (task, fn, taskname))

        pid, pipein, pipeout = fork_off_task(self.cookercfg, self.data, self.workerdata, fn, task, taskname, appends, taskdepdata, quieterrors)

        self.build_pids[pid] = task
        self.build_pipes[pid] = runQueueWorkerPipe(pipein, pipeout)

    def process_waitpid(self):
        """
        Return none is there are no processes awaiting result collection, otherwise
        collect the process exit codes and close the information pipe.
        """
        try:
            pid, status = os.waitpid(-1, os.WNOHANG)
            if pid == 0 or os.WIFSTOPPED(status):
                return None
        except OSError:
            return None

        workerlog_write("Exit code of %s for pid %s\n" % (status, pid))

        if os.WIFEXITED(status):
            status = os.WEXITSTATUS(status)
        elif os.WIFSIGNALED(status):
            # Per shell conventions for $?, when a process exits due to
            # a signal, we return an exit code of 128 + SIGNUM
            status = 128 + os.WTERMSIG(status)

        task = self.build_pids[pid]
        del self.build_pids[pid]

        self.build_pipes[pid].close()
        del self.build_pipes[pid]

        worker_fire_prepickled("<exitcode>" + pickle.dumps((task, status)) + "</exitcode>")

    def handle_finishnow(self, _):
        if self.build_pids:
            logger.info("Sending SIGTERM to remaining %s tasks", len(self.build_pids))
            for k, v in self.build_pids.iteritems():
                try:
                    os.kill(-k, signal.SIGTERM)
                    os.waitpid(-1, 0)
                except:
                    pass
        for pipe in self.build_pipes:
            self.build_pipes[pipe].read()

try:
    worker = BitbakeWorker(sys.stdin)
    worker.serve()
except BaseException as e:
    if not normalexit:
        import traceback
        sys.stderr.write(traceback.format_exc())
        sys.stderr.write(str(e))
while len(worker_queue):
    worker_flush()
workerlog_write("exitting")
sys.exit(0)