Rename jwack.py -> jobserver.py.

I'm not really sure why I called it jwack.  I think it was kind of a
wack jobserver(tm).  But nowadays most of the wack-ness is gone.

redo/builder.py

@@ -1,5 +1,5 @@
 import sys, os, errno, stat, signal, time
-import vars, jwack, state, paths
+import vars, jobserver, state, paths
 from helpers import unlink, close_on_exec
 import logs
 from logs import debug2, err, warn, meta, check_tty
@@ -221,7 +221,7 @@ class BuildJob(object):
         dof.save()
         state.commit()
         meta('do', state.target_relpath(t))
-        jwack.start_job(t, self._do_subproc, self._after)
+        jobserver.start_job(t, self._do_subproc, self._after)
 
     def _start_unlocked(self, dirty):
         # out-of-band redo of some sub-objects.  This happens when we're not
@@ -250,7 +250,7 @@ class BuildJob(object):
             # returns only if there's an exception
         def after(t, rv):
             return self._after2(rv)
-        jwack.start_job(self.t, run, after)
+        jobserver.start_job(self.t, run, after)
 
     def _do_subproc(self):
         # careful: REDO_PWD was the PWD relative to the STARTPATH at the time
@@ -432,9 +432,9 @@ def main(targets, shouldbuildfunc):
         if t in seen:
             continue
         seen[t] = 1
-        if not jwack.has_token():
+        if not jobserver.has_token():
             state.commit()
-        jwack.ensure_token_or_cheat(t, cheat)
+        jobserver.ensure_token_or_cheat(t, cheat)
         if retcode[0] and not vars.KEEP_GOING:
             break
         if not state.check_sane():
@@ -471,11 +471,11 @@ def main(targets, shouldbuildfunc):
     # do anything.  The only exception is if we're invoked as redo instead
     # of redo-ifchange; then we have to redo it even if someone else already
     # did.  But that should be rare.
-    while locked or jwack.running():
+    while locked or jobserver.running():
         state.commit()
-        jwack.wait_all()
-        assert jwack._mytokens == 0  # pylint: disable=protected-access
-        jwack.ensure_token_or_cheat('self', cheat)
+        jobserver.wait_all()
+        assert jobserver._mytokens == 0  # pylint: disable=protected-access
+        jobserver.ensure_token_or_cheat('self', cheat)
         # at this point, we don't have any children holding any tokens, so
         # it's okay to block below.
         if retcode[0] and not vars.KEEP_GOING:
@@ -507,12 +507,12 @@ def main(targets, shouldbuildfunc):
                 # give up our personal token while we wait for the lock to
                 # be released; but we should never run ensure_token() while
                 # holding a lock, or we could cause deadlocks.
-                jwack.release_mine()
+                jobserver.release_mine()
                 lock.waitlock()
                 # now t is definitely free, so we get to decide whether
                 # to build it.
                 lock.unlock()
-                jwack.ensure_token_or_cheat(t, cheat)
+                jobserver.ensure_token_or_cheat(t, cheat)
                 lock.trylock()
             assert lock.owned
             meta('unlocked', state.target_relpath(t))

redo/cmd_ifchange.py

@@ -3,7 +3,7 @@ import os, sys, traceback
 import vars_init
 vars_init.init(sys.argv[1:])
 
-import vars, state, builder, jwack, deps
+import vars, state, builder, jobserver, deps
 from logs import debug2, err
 
 def should_build(t):
@@ -32,7 +32,7 @@ def main():
         else:
             f = me = None
             debug2('redo-ifchange: not adding depends.\n')
-        jwack.setup(1)
+        jobserver.setup(1)
         try:
             targets = sys.argv[1:]
             if f:
@@ -46,7 +46,7 @@ def main():
                 state.rollback()
             finally:
                 try:
-                    jwack.force_return_tokens()
+                    jobserver.force_return_tokens()
                 except Exception, e:  # pylint: disable=broad-except
                     traceback.print_exc(100, sys.stderr)
                     err('unexpected error: %r\n' % e)

redo/cmd_redo.py

@@ -74,7 +74,7 @@ if opt.no_log:
 import vars_init
 vars_init.init(targets)
 
-import vars, state, builder, jwack
+import vars, state, builder, jobserver
 from logs import warn, err
 
 def main():
@@ -97,7 +97,7 @@ def main():
 
         if j < 1 or j > 1000:
             err('invalid --jobs value: %r\n' % opt.jobs)
-        jwack.setup(j)
+        jobserver.setup(j)
         try:
             assert state.is_flushed()
             retcode = builder.main(targets, lambda t: (True, True))
@@ -107,7 +107,7 @@ def main():
                 state.rollback()
             finally:
                 try:
-                    jwack.force_return_tokens()
+                    jobserver.force_return_tokens()
                 except Exception, e:  # pylint: disable=broad-except
                     traceback.print_exc(100, sys.stderr)
                     err('unexpected error: %r\n' % e)

redo/jobserver.py

@@ -88,7 +88,7 @@ _waitfds = {}
 
 def _debug(s):
     if 0:
-        sys.stderr.write('jwack#%d: %s' % (os.getpid(), s))
+        sys.stderr.write('job#%d: %s' % (os.getpid(), s))
 
 
 def _create_tokens(n):