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Diffstat (limited to 'scons/scons-local-2.0.1/SCons/Job.py')
| -rw-r--r-- | scons/scons-local-2.0.1/SCons/Job.py | 435 |
1 files changed, 0 insertions, 435 deletions
diff --git a/scons/scons-local-2.0.1/SCons/Job.py b/scons/scons-local-2.0.1/SCons/Job.py deleted file mode 100644 index 7866bb40..00000000 --- a/scons/scons-local-2.0.1/SCons/Job.py +++ /dev/null @@ -1,435 +0,0 @@ -"""SCons.Job - -This module defines the Serial and Parallel classes that execute tasks to -complete a build. The Jobs class provides a higher level interface to start, -stop, and wait on jobs. - -""" - -# -# Copyright (c) 2001, 2002, 2003, 2004, 2005, 2006, 2007, 2008, 2009, 2010 The SCons Foundation -# -# Permission is hereby granted, free of charge, to any person obtaining -# a copy of this software and associated documentation files (the -# "Software"), to deal in the Software without restriction, including -# without limitation the rights to use, copy, modify, merge, publish, -# distribute, sublicense, and/or sell copies of the Software, and to -# permit persons to whom the Software is furnished to do so, subject to -# the following conditions: -# -# The above copyright notice and this permission notice shall be included -# in all copies or substantial portions of the Software. -# -# THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY -# KIND, EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE -# WARRANTIES OF MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND -# NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE -# LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION -# OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION -# WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE. -# - -__revision__ = "src/engine/SCons/Job.py 5134 2010/08/16 23:02:40 bdeegan" - -import SCons.compat - -import os -import signal - -import SCons.Errors - -# The default stack size (in kilobytes) of the threads used to execute -# jobs in parallel. -# -# We use a stack size of 256 kilobytes. The default on some platforms -# is too large and prevents us from creating enough threads to fully -# parallelized the build. For example, the default stack size on linux -# is 8 MBytes. - -explicit_stack_size = None -default_stack_size = 256 - -interrupt_msg = 'Build interrupted.' - - -class InterruptState(object): - def __init__(self): - self.interrupted = False - - def set(self): - self.interrupted = True - - def __call__(self): - return self.interrupted - - -class Jobs(object): - """An instance of this class initializes N jobs, and provides - methods for starting, stopping, and waiting on all N jobs. - """ - - def __init__(self, num, taskmaster): - """ - create 'num' jobs using the given taskmaster. - - If 'num' is 1 or less, then a serial job will be used, - otherwise a parallel job with 'num' worker threads will - be used. - - The 'num_jobs' attribute will be set to the actual number of jobs - allocated. If more than one job is requested but the Parallel - class can't do it, it gets reset to 1. Wrapping interfaces that - care should check the value of 'num_jobs' after initialization. - """ - - self.job = None - if num > 1: - stack_size = explicit_stack_size - if stack_size is None: - stack_size = default_stack_size - - try: - self.job = Parallel(taskmaster, num, stack_size) - self.num_jobs = num - except NameError: - pass - if self.job is None: - self.job = Serial(taskmaster) - self.num_jobs = 1 - - def run(self, postfunc=lambda: None): - """Run the jobs. - - postfunc() will be invoked after the jobs has run. It will be - invoked even if the jobs are interrupted by a keyboard - interrupt (well, in fact by a signal such as either SIGINT, - SIGTERM or SIGHUP). The execution of postfunc() is protected - against keyboard interrupts and is guaranteed to run to - completion.""" - self._setup_sig_handler() - try: - self.job.start() - finally: - postfunc() - self._reset_sig_handler() - - def were_interrupted(self): - """Returns whether the jobs were interrupted by a signal.""" - return self.job.interrupted() - - def _setup_sig_handler(self): - """Setup an interrupt handler so that SCons can shutdown cleanly in - various conditions: - - a) SIGINT: Keyboard interrupt - b) SIGTERM: kill or system shutdown - c) SIGHUP: Controlling shell exiting - - We handle all of these cases by stopping the taskmaster. It - turns out that it very difficult to stop the build process - by throwing asynchronously an exception such as - KeyboardInterrupt. For example, the python Condition - variables (threading.Condition) and queue's do not seem to - asynchronous-exception-safe. It would require adding a whole - bunch of try/finally block and except KeyboardInterrupt all - over the place. - - Note also that we have to be careful to handle the case when - SCons forks before executing another process. In that case, we - want the child to exit immediately. - """ - def handler(signum, stack, self=self, parentpid=os.getpid()): - if os.getpid() == parentpid: - self.job.taskmaster.stop() - self.job.interrupted.set() - else: - os._exit(2) - - self.old_sigint = signal.signal(signal.SIGINT, handler) - self.old_sigterm = signal.signal(signal.SIGTERM, handler) - try: - self.old_sighup = signal.signal(signal.SIGHUP, handler) - except AttributeError: - pass - - def _reset_sig_handler(self): - """Restore the signal handlers to their previous state (before the - call to _setup_sig_handler().""" - - signal.signal(signal.SIGINT, self.old_sigint) - signal.signal(signal.SIGTERM, self.old_sigterm) - try: - signal.signal(signal.SIGHUP, self.old_sighup) - except AttributeError: - pass - -class Serial(object): - """This class is used to execute tasks in series, and is more efficient - than Parallel, but is only appropriate for non-parallel builds. Only - one instance of this class should be in existence at a time. - - This class is not thread safe. - """ - - def __init__(self, taskmaster): - """Create a new serial job given a taskmaster. - - The taskmaster's next_task() method should return the next task - that needs to be executed, or None if there are no more tasks. The - taskmaster's executed() method will be called for each task when it - is successfully executed or failed() will be called if it failed to - execute (e.g. execute() raised an exception).""" - - self.taskmaster = taskmaster - self.interrupted = InterruptState() - - def start(self): - """Start the job. This will begin pulling tasks from the taskmaster - and executing them, and return when there are no more tasks. If a task - fails to execute (i.e. execute() raises an exception), then the job will - stop.""" - - while True: - task = self.taskmaster.next_task() - - if task is None: - break - - try: - task.prepare() - if task.needs_execute(): - task.execute() - except: - if self.interrupted(): - try: - raise SCons.Errors.BuildError( - task.targets[0], errstr=interrupt_msg) - except: - task.exception_set() - else: - task.exception_set() - - # Let the failed() callback function arrange for the - # build to stop if that's appropriate. - task.failed() - else: - task.executed() - - task.postprocess() - self.taskmaster.cleanup() - - -# Trap import failure so that everything in the Job module but the -# Parallel class (and its dependent classes) will work if the interpreter -# doesn't support threads. -try: - import queue - import threading -except ImportError: - pass -else: - class Worker(threading.Thread): - """A worker thread waits on a task to be posted to its request queue, - dequeues the task, executes it, and posts a tuple including the task - and a boolean indicating whether the task executed successfully. """ - - def __init__(self, requestQueue, resultsQueue, interrupted): - threading.Thread.__init__(self) - self.setDaemon(1) - self.requestQueue = requestQueue - self.resultsQueue = resultsQueue - self.interrupted = interrupted - self.start() - - def run(self): - while True: - task = self.requestQueue.get() - - if task is None: - # The "None" value is used as a sentinel by - # ThreadPool.cleanup(). This indicates that there - # are no more tasks, so we should quit. - break - - try: - if self.interrupted(): - raise SCons.Errors.BuildError( - task.targets[0], errstr=interrupt_msg) - task.execute() - except: - task.exception_set() - ok = False - else: - ok = True - - self.resultsQueue.put((task, ok)) - - class ThreadPool(object): - """This class is responsible for spawning and managing worker threads.""" - - def __init__(self, num, stack_size, interrupted): - """Create the request and reply queues, and 'num' worker threads. - - One must specify the stack size of the worker threads. The - stack size is specified in kilobytes. - """ - self.requestQueue = queue.Queue(0) - self.resultsQueue = queue.Queue(0) - - try: - prev_size = threading.stack_size(stack_size*1024) - except AttributeError, e: - # Only print a warning if the stack size has been - # explicitly set. - if not explicit_stack_size is None: - msg = "Setting stack size is unsupported by this version of Python:\n " + \ - e.args[0] - SCons.Warnings.warn(SCons.Warnings.StackSizeWarning, msg) - except ValueError, e: - msg = "Setting stack size failed:\n " + str(e) - SCons.Warnings.warn(SCons.Warnings.StackSizeWarning, msg) - - # Create worker threads - self.workers = [] - for _ in range(num): - worker = Worker(self.requestQueue, self.resultsQueue, interrupted) - self.workers.append(worker) - - if 'prev_size' in locals(): - threading.stack_size(prev_size) - - def put(self, task): - """Put task into request queue.""" - self.requestQueue.put(task) - - def get(self): - """Remove and return a result tuple from the results queue.""" - return self.resultsQueue.get() - - def preparation_failed(self, task): - self.resultsQueue.put((task, False)) - - def cleanup(self): - """ - Shuts down the thread pool, giving each worker thread a - chance to shut down gracefully. - """ - # For each worker thread, put a sentinel "None" value - # on the requestQueue (indicating that there's no work - # to be done) so that each worker thread will get one and - # terminate gracefully. - for _ in self.workers: - self.requestQueue.put(None) - - # Wait for all of the workers to terminate. - # - # If we don't do this, later Python versions (2.4, 2.5) often - # seem to raise exceptions during shutdown. This happens - # in requestQueue.get(), as an assertion failure that - # requestQueue.not_full is notified while not acquired, - # seemingly because the main thread has shut down (or is - # in the process of doing so) while the workers are still - # trying to pull sentinels off the requestQueue. - # - # Normally these terminations should happen fairly quickly, - # but we'll stick a one-second timeout on here just in case - # someone gets hung. - for worker in self.workers: - worker.join(1.0) - self.workers = [] - - class Parallel(object): - """This class is used to execute tasks in parallel, and is somewhat - less efficient than Serial, but is appropriate for parallel builds. - - This class is thread safe. - """ - - def __init__(self, taskmaster, num, stack_size): - """Create a new parallel job given a taskmaster. - - The taskmaster's next_task() method should return the next - task that needs to be executed, or None if there are no more - tasks. The taskmaster's executed() method will be called - for each task when it is successfully executed or failed() - will be called if the task failed to execute (i.e. execute() - raised an exception). - - Note: calls to taskmaster are serialized, but calls to - execute() on distinct tasks are not serialized, because - that is the whole point of parallel jobs: they can execute - multiple tasks simultaneously. """ - - self.taskmaster = taskmaster - self.interrupted = InterruptState() - self.tp = ThreadPool(num, stack_size, self.interrupted) - - self.maxjobs = num - - def start(self): - """Start the job. This will begin pulling tasks from the - taskmaster and executing them, and return when there are no - more tasks. If a task fails to execute (i.e. execute() raises - an exception), then the job will stop.""" - - jobs = 0 - - while True: - # Start up as many available tasks as we're - # allowed to. - while jobs < self.maxjobs: - task = self.taskmaster.next_task() - if task is None: - break - - try: - # prepare task for execution - task.prepare() - except: - task.exception_set() - task.failed() - task.postprocess() - else: - if task.needs_execute(): - # dispatch task - self.tp.put(task) - jobs = jobs + 1 - else: - task.executed() - task.postprocess() - - if not task and not jobs: break - - # Let any/all completed tasks finish up before we go - # back and put the next batch of tasks on the queue. - while True: - task, ok = self.tp.get() - jobs = jobs - 1 - - if ok: - task.executed() - else: - if self.interrupted(): - try: - raise SCons.Errors.BuildError( - task.targets[0], errstr=interrupt_msg) - except: - task.exception_set() - - # Let the failed() callback function arrange - # for the build to stop if that's appropriate. - task.failed() - - task.postprocess() - - if self.tp.resultsQueue.empty(): - break - - self.tp.cleanup() - self.taskmaster.cleanup() - -# Local Variables: -# tab-width:4 -# indent-tabs-mode:nil -# End: -# vim: set expandtab tabstop=4 shiftwidth=4: |