Merged revisions 2725-2865 via svnmerge from

http://scons.tigris.org/svn/scons/branches/core

........
  r2731 | stevenknight | 2008-04-01 09:22:37 -0700 (Tue, 01 Apr 2008) | 4 lines

  Fix test/Interactive/version.py, which still had the old hard-coded
  Copyright string, by moving the test copy of the Copyright string
  into QMTest/TestSCons.py, where it's available to all test scripts.
........
  r2732 | stevenknight | 2008-04-02 13:28:32 -0700 (Wed, 02 Apr 2008) | 3 lines

  Issues 317, 323, 329:  Ignore the -d, -e and -w options, which we're
  not going to implement.
........
  r2734 | stevenknight | 2008-04-05 07:50:49 -0700 (Sat, 05 Apr 2008) | 2 lines

  Fix bootstrap.py for pre-2.3 versions of Python, which don't have __file__.
........
  r2735 | stevenknight | 2008-04-05 07:54:44 -0700 (Sat, 05 Apr 2008) | 2 lines

  Fix the non-breaking-hyphen regular expression(s) for Python 1.5.
........
  r2736 | garyo | 2008-04-05 19:15:52 -0700 (Sat, 05 Apr 2008) | 1 line

  Added Users Guide section for AddMethod.
........
  r2737 | stevenknight | 2008-04-08 09:43:31 -0700 (Tue, 08 Apr 2008) | 3 lines

  Don't raise strings as exceptions in the exception-handling unit tests.
  That's now deprecated Python behavior.
........
  r2738 | stevenknight | 2008-04-08 10:36:00 -0700 (Tue, 08 Apr 2008) | 5 lines

  Address a serious inefficiency in Java builds by moving the pre-build
  check for whether source files exist from the Node class to the Executor
  class, so we only have to perform the check once when building a whole
  bunch of targets from a whole bunch of sources.
........
  r2739 | stevenknight | 2008-04-08 13:53:44 -0700 (Tue, 08 Apr 2008) | 2 lines

  Add a backwards-compatibility version of the "itertools" module.
........
  r2740 | stevenknight | 2008-04-08 14:12:05 -0700 (Tue, 08 Apr 2008) | 2 lines

  Issue 1961:  speed up SCons.Util.to_String*() functions.  (Benoit Belley)
........
  r2741 | stevenknight | 2008-04-08 14:15:36 -0700 (Tue, 08 Apr 2008) | 2 lines

  Use the itertools.izip() method for some key Node.FS methods.  (Benoit Belley)
........
  r2742 | stevenknight | 2008-04-08 14:35:35 -0700 (Tue, 08 Apr 2008) | 2 lines

  Issues 1961:  use izip() instead of zip() where possible (Benoit Belley)
........
  r2743 | stevenknight | 2008-04-08 14:48:08 -0700 (Tue, 08 Apr 2008) | 3 lines

  Issue 1961:  more efficient get_contents() implementation for Python
  function Actions.  (Benoit Belley)
........
  r2744 | stevenknight | 2008-04-08 17:55:30 -0700 (Tue, 08 Apr 2008) | 3 lines

  Issue 1961:  make SCons.Node.* state variables global in Taskmaster.py so
  we avoid unneceesary attribute fetches.  (Benoit Belley)
........
  r2745 | stevenknight | 2008-04-08 20:40:31 -0700 (Tue, 08 Apr 2008) | 2 lines

  Issue 1961:  Optimize the code in Node.get_binfo().  (Benoit Belley)
........
  r2746 | stevenknight | 2008-04-08 21:05:17 -0700 (Tue, 08 Apr 2008) | 3 lines

  Issue 1961:  Enhance the backwards-compatibility sets() module with the
  ability to compare sets.  (Benoit Belley)
........
  r2747 | stevenknight | 2008-04-08 22:11:20 -0700 (Tue, 08 Apr 2008) | 2 lines

  Issue 1961:  Optimize Executor.scan().  (Benoit Belley)
........
  r2748 | stevenknight | 2008-04-08 22:17:55 -0700 (Tue, 08 Apr 2008) | 3 lines

  Python 1.5 compatibility:  use for p in paths.keys() for dictionaries.
  (Benoit Belley)
........
  r2749 | stevenknight | 2008-04-08 22:54:02 -0700 (Tue, 08 Apr 2008) | 10 lines

  Issue 1961:  additional build optimizations:
  --  Make taskmastertrace output more useful and readable.
  --  Move dependency cycle checking to avoid re-doing it.
  --  Have Nodes use sets, not dictionaries, to track various things.
  --  Eliminate intermediate function calls from fetching Node children.
  --  Add a Task.needs_execute() method to avoid doing that check over and
      over as part of needs_execute().
  --  Remove the unused Node.found_includes attribute.
  (Benoit Belley)
........
  r2750 | stevenknight | 2008-04-09 14:47:44 -0700 (Wed, 09 Apr 2008) | 4 lines

  Make target Java .class files depend *only* on the input .java files as
  their sources when determining if they require rebuilding.  This eliminates
  O(NxM) checking for every single edge in a big, overly-connected DAG mesh.
........
  r2751 | stevenknight | 2008-04-09 16:58:41 -0700 (Wed, 09 Apr 2008) | 2 lines

  Remove 0.95 and 0.96* release notes.
........
  r2752 | stevenknight | 2008-04-10 02:24:50 -0700 (Thu, 10 Apr 2008) | 2 lines

  Issue 1956:  Fix --debug=stree printing its tree twice.  (Benoit Belley)
........
  r2753 | stevenknight | 2008-04-10 02:33:28 -0700 (Thu, 10 Apr 2008) | 2 lines

  Issue 1896:  Add support for the GDC D language compiler.  (Matthew Wesley)
........
  r2754 | stevenknight | 2008-04-10 02:39:24 -0700 (Thu, 10 Apr 2008) | 2 lines

  Fix tabs.
........
  r2755 | stevenknight | 2008-04-10 02:41:50 -0700 (Thu, 10 Apr 2008) | 3 lines

  Issue 1964:  Fix passing variable names in a list to Return() (as
  already documented in the man page!)  (Mike Wake)
........
  r2756 | stevenknight | 2008-04-10 02:55:40 -0700 (Thu, 10 Apr 2008) | 2 lines

  Support the ability to download 2.6 candidate releases (e.g. 2.6a2).
........
  r2757 | stevenknight | 2008-04-10 02:58:35 -0700 (Thu, 10 Apr 2008) | 3 lines

  Issue 1669:  Fix the ability to use LoadableModule() under MinGW.
  (Johan Boule)
........
  r2758 | stevenknight | 2008-04-10 03:03:15 -0700 (Thu, 10 Apr 2008) | 3 lines

  Update the test/Interactive/tree.py script for Benoit's fix to
  remove duplicate tree printing.
........
  r2759 | stevenknight | 2008-04-10 06:43:44 -0700 (Thu, 10 Apr 2008) | 3 lines

  Fix Tool/dmd.py when no D compiler is installed -- we don't want to
  search for a path if the result is None.
........
  r2760 | GregNoel | 2008-04-10 15:30:34 -0700 (Thu, 10 Apr 2008) | 1 line

  Issue 2009: separate Debug.caller() by functionality
........
  r2761 | stevenknight | 2008-04-11 04:47:25 -0700 (Fri, 11 Apr 2008) | 3 lines

  Issue 1882:  Add the scons.bat directory to %PATH% so it can find python.exe.
  (Anatoly Techtonik)
........
  r2762 | stevenknight | 2008-04-11 09:15:22 -0700 (Fri, 11 Apr 2008) | 4 lines

  Issues 1835,1901:  fix the ability to list a source file multiple
  times for a target by making sure we only store unique entries in the
  .sconsign file.
........
  r2763 | stevenknight | 2008-04-11 10:58:26 -0700 (Fri, 11 Apr 2008) | 4 lines

  Issue 1882:  Fix earlier patch to scons.bat by adding ~dp0;~dp0.. to
  the front of %PATH%, and only executing endlocal on NT-based systems.
  (Anatoly Techtonik)
........
  r2764 | stevenknight | 2008-04-11 13:06:29 -0700 (Fri, 11 Apr 2008) | 4 lines

  Add a Variables object and {Bool,Envum,List,Package,Path}Variable()
  functions as a first step towards eventually deprecating the
  Options object and {Bool,Envum,List,Package,Path}Option() functions.
........
  r2765 | stevenknight | 2008-04-11 18:13:53 -0700 (Fri, 11 Apr 2008) | 3 lines

  Issue 1962:  Capture a test case for ListActions that contain a
  command-line string containing unicode, and Python FunctionAction.
........
  r2766 | stevenknight | 2008-04-11 22:03:14 -0700 (Fri, 11 Apr 2008) | 3 lines

  Issue 1933:  expect .py files generated by the SWIG -python option
  to be in the same (sub)directory as the target.
........
  r2767 | stevenknight | 2008-04-12 06:41:57 -0700 (Sat, 12 Apr 2008) | 2 lines

  Remove the SCons.Options package in favor of the new SCons.Variables package.
........
  r2768 | stevenknight | 2008-04-12 13:33:52 -0700 (Sat, 12 Apr 2008) | 5 lines

  Issue 1971:  Move the incorporation of $CCFLAGS and $SHCCFLAGS directly
  into the C++ command lines (${SHCXX,CXX}COM) instead of through indirect
  expansion of $CXXFLAGS and $SHCXXFLAGS.  This requires removing -fPIC
  from the default setting of $SHCXXFLAGS under the GNU toolchain.
........
  r2769 | stevenknight | 2008-04-13 07:01:27 -0700 (Sun, 13 Apr 2008) | 3 lines

  Fix __all__ definitions in the Variables/*Variable.py file that were
  cause epydoc to blow up when generating developer documentation.
........
  r2770 | stevenknight | 2008-04-13 11:47:49 -0700 (Sun, 13 Apr 2008) | 3 lines

  Add variables= keyword argument to Environment() creation as a first
  step towards deprecating options=.
........
  r2771 | stevenknight | 2008-04-13 11:54:19 -0700 (Sun, 13 Apr 2008) | 2 lines

  Correct underscore-instead-of-hyphen misspellings in option names.
........
  r2772 | bdbaddog | 2008-04-13 17:39:21 -0700 (Sun, 13 Apr 2008) | 3 lines

  Changes to fix 15 tests which were failing on cygwin.
........
  r2773 | GregNoel | 2008-04-13 22:31:07 -0700 (Sun, 13 Apr 2008) | 1 line

  Various fixes to tests on Darwin using 1.5.2
........
  r2774 | stevenknight | 2008-04-14 15:00:44 -0700 (Mon, 14 Apr 2008) | 2 lines

  Python 1.5.2 fix in new test/SWIG/subdir.py script (use the -classic option).
........
  r2775 | belley | 2008-04-14 18:02:40 -0700 (Mon, 14 Apr 2008) | 32 lines

  Dont use KeyboardInterrupt to stop a build! [Issue 1907]

  SCons would often hang after pressing Ctrl-C. I started investigating and I
  realized that most of the Python libraries are not really safe with respect to
  asynchronous exceptions. Although,there are enough try/finally blocks to handle
  exceptions thrown synchronously by the library code, the Python libraries are
  not always protected against exceptions being thrown asynchronously, such as a
  KeyboardInterrupt being thrown at a completely random location.

  For example, the function Queue.empty() does not protect its mutex with a
  try/finally block. If the KeyboardInterrupt exception gets thrown while the
  mutex is held, any further attempt to access the Queue will lead to dead-lock
  (explaining why SCons hangs sometimes after pressing CTRL-C). Even the
  threading.Condition condition variables are not async-exception safe. It
  therefore seems a lost battle to try to stop a build by raising an exception.

  Instead, I have implemented a signal handler that tells the Jobs (and its
  associated Taskmaster) to stop the build. I have been careful to wait after the
  .sconsign file has been written back to re-install the default SIGINT signal
  handler that raises a KeyboardInterrupt exception.

  This patch is submitted against changeset 2773 of branches/core. The
  regression test suite has been run on RHEL4 using Pyhon 2.5.1 and
  1.5.2. My team has been using an SCons build with this patch for a
  while now on Windows, Linux and OSX.

  See:
  http://scons.tigris.org/issues/show_bug.cgi?id=1907

  Benoit Belley
........
  r2777 | cournape | 2008-04-14 20:11:56 -0700 (Mon, 14 Apr 2008) | 3 lines

  Initialized merge tracking via "svnmerge" with revisions "1-2776" from
  http://scons.tigris.org/svn/scons/branches/fortran_refactor
........
  r2788 | stevenknight | 2008-04-14 22:09:27 -0700 (Mon, 14 Apr 2008) | 2 lines

  Fix the print the "script" line in the --version output.
........
  r2789 | stevenknight | 2008-04-14 22:18:27 -0700 (Mon, 14 Apr 2008) | 2 lines

  Add a __COPYRIGHT__ line.
........
  r2790 | stevenknight | 2008-04-14 22:20:39 -0700 (Mon, 14 Apr 2008) | 3 lines

  Issue 2008:  in checkpoint releases, use a '.' to separate (e.g.) 0.98.0
  from 0d20080414.
........
  r2817 | belley | 2008-04-15 06:44:21 -0700 (Tue, 15 Apr 2008) | 13 lines

  TestSCons.up_to_date() should use match_re_dotall

  I changed TestSCons.up_to_date() to use match_re_dotall instead of
  match_exact. This is necessary so that I can call up_to_date() with
  the TestSCons.deprecated_python_expr error message in one of my test.

  Note that TestSCons.not_up_to_date() is already using match_re_dotall.

  Ran the test suite on both Python 2.5.1 and 1.5.2.

  Benoit
........
  r2818 | belley | 2008-04-15 12:10:52 -0700 (Tue, 15 Apr 2008) | 10 lines

  Improved the multiple-parents.py test to also tests the following
  cases:

  d) Some children are ignored
  e) Some children are pre-requesites
  f) Some sources are missing

  The test still passes. No extra bug were found.
........
  r2850 | stevenknight | 2008-04-16 11:15:24 -0700 (Wed, 16 Apr 2008) | 4 lines

  Fix problems with the __del__() method referencing other module functions
  through global variables, which can get deleted out from under us at
  shutdown.
........
  r2851 | stevenknight | 2008-04-16 11:17:07 -0700 (Wed, 16 Apr 2008) | 4 lines

  Fix use of --interactive with -u/-U/-D and VariantDir() by making the
  method that cleans Node states between interactive commands aware of
  the alter_targets() method that tells us about an associated VariantDir().
........

1 files changed, 109 insertions, 42 deletions

diff --git a/src/engine/SCons/Job.py b/src/engine/SCons/Job.py
index 7b51409..d93952c 100644
--- a/src/engine/SCons/Job.py
+++ b/src/engine/SCons/Job.py
@@ -33,6 +33,9 @@ __revision__ = "__FILE__ __REVISION__ __DATE__ __DEVELOPER__"
 
 import SCons.compat
 
+import os
+import signal
+
 
 # The default stack size (in kilobytes) of the threads used to execute
 # jobs in parallel.
@@ -44,6 +47,7 @@ import SCons.compat
 
 default_stack_size = 256
 
+interrupt_msg = 'Build interrupted.'
 
 class Jobs:
     """An instance of this class initializes N jobs, and provides
@@ -80,21 +84,73 @@ class Jobs:
             self.job = Serial(taskmaster)
             self.num_jobs = 1
 
-    def run(self):
-        """run the job"""
+        self.job.interrupted = False
+
+    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()
-        except KeyboardInterrupt:
-            # mask any further keyboard interrupts so that scons
-            # can shutdown cleanly:
-            # (this only masks the keyboard interrupt for Python,
-            #  child processes can still get the keyboard interrupt)
-            import signal
-            signal.signal(signal.SIGINT, signal.SIG_IGN)
-            raise
-
-    def cleanup(self):
-        self.job.cleanup()
+        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, parentpid=os.getpid()):
+            if os.getpid() == parentpid:
+                self.job.taskmaster.stop()
+                self.job.interrupted = True
+            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:
     """This class is used to execute tasks in series, and is more efficient
@@ -129,11 +185,18 @@ class Serial:
 
             try:
                 task.prepare()
-                task.execute()
-            except KeyboardInterrupt:
-                raise
+                if task.needs_execute():
+                    task.execute()
             except:
-                task.exception_set()
+                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()
@@ -141,9 +204,8 @@ class Serial:
                 task.executed()
 
             task.postprocess()
+        self.taskmaster.cleanup()
 
-    def cleanup(self):
-        pass
 
 # Trap import failure so that everything in the Job module but the
 # Parallel class (and its dependent classes) will work if the interpreter
@@ -178,9 +240,6 @@ else:
 
                 try:
                     task.execute()
-                except KeyboardInterrupt:
-                    # be explicit here for test/interrupts.py
-                    ok = False
                 except:
                     task.exception_set()
                     ok = False
@@ -226,16 +285,16 @@ else:
             if 'prev_size' in locals().keys():
                 threading.stack_size(prev_size)
 
-        def put(self, obj):
+        def put(self, task):
             """Put task into request queue."""
-            self.requestQueue.put(obj)
+            self.requestQueue.put(task)
 
-        def get(self, block = True):
+        def get(self):
             """Remove and return a result tuple from the results queue."""
-            return self.resultsQueue.get(block)
+            return self.resultsQueue.get()
 
-        def preparation_failed(self, obj):
-            self.resultsQueue.put((obj, False))
+        def preparation_failed(self, task):
+            self.resultsQueue.put((task, False))
 
         def cleanup(self):
             """
@@ -309,22 +368,21 @@ else:
                     if task is None:
                         break
 
-                    # prepare task for execution
                     try:
+                        # prepare task for execution
                         task.prepare()
-                    except KeyboardInterrupt:
-                        raise
                     except:
-                        # Let the failed() callback function arrange
-                        # for the build to stop if that's appropriate.
                         task.exception_set()
-                        self.tp.preparation_failed(task)
-                        jobs = jobs + 1
-                        continue
-
-                    # dispatch task
-                    self.tp.put(task)
-                    jobs = jobs + 1
+                        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
 
@@ -332,11 +390,20 @@ else:
                 # back and put the next batch of tasks on the queue.
                 while 1:
                     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()
@@ -344,5 +411,5 @@ else:
                     if self.tp.resultsQueue.empty():
                         break
 
-        def cleanup(self):
             self.tp.cleanup()
+            self.taskmaster.cleanup()