When logging is disabled, make the EbuildPhase create a dummy pipe to provide

a file descriptor that the scheduler can use to monitor the process from
inside a poll() loop.

svn path=/main/trunk/; revision=10920

diff --git a/pym/_emerge/__init__.py b/pym/_emerge/__init__.py
index 25cbc3bb5270cbe2323ff8a245bc5a354a856c47..b02d347bc03a6430bc37191df912743c052d9d87 100644 (file)
--- a/pym/_emerge/__init__.py
+++ b/pym/_emerge/__init__.py
@@ -1881,6 +1881,11 @@ class EbuildPhase(SubProcess):
        _files_dict = slot_dict_class(_file_names, prefix="")
        _bufsize = 4096
 
+       # A file descriptor is required for the scheduler to monitor changes from
+       # inside a poll() loop. When logging is not enabled, create a pipe just to
+       # serve this purpose alone.
+       _dummy_pipe_fd = 9
+
        def start(self):
                root_config = self.pkg.root_config
                tree = self.tree
@@ -1931,7 +1936,6 @@ class EbuildPhase(SubProcess):
                                mode[1] &= ~termios.OPOST
                                termios.tcsetattr(slave_fd, termios.TCSANOW, mode)
 
-                       import fcntl
                        fcntl.fcntl(master_fd, fcntl.F_SETFL,
                                fcntl.fcntl(master_fd, fcntl.F_GETFL) | os.O_NONBLOCK)
 
@@ -1945,6 +1949,17 @@ class EbuildPhase(SubProcess):
                        fd_pipes[1] = slave_fd
                        fd_pipes[2] = slave_fd
 
+               else:
+                       # Create a dummy pipe so the scheduler can monitor
+                       # the process from inside a poll() loop.
+                       master_fd, slave_fd = os.pipe()
+                       fcntl.fcntl(master_fd, fcntl.F_SETFL,
+                               fcntl.fcntl(master_fd, fcntl.F_GETFL) | os.O_NONBLOCK)
+                       fd_pipes.setdefault(0, sys.stdin.fileno())
+                       fd_pipes.setdefault(1, sys.stdout.fileno())
+                       fd_pipes.setdefault(2, sys.stderr.fileno())
+                       fd_pipes[self._dummy_pipe_fd] = slave_fd
+
                retval = portage.doebuild(ebuild_path, self.phase,
                        root_config.root, settings, debug,
                        mydbapi=mydbapi, tree=tree,
@@ -1953,13 +1968,16 @@ class EbuildPhase(SubProcess):
                self.pid = retval[0]
 
                if logfile:
-                       os.close(slave_fd)
                        files.log = open(logfile, 'a')
                        files.stdout = os.fdopen(os.dup(fd_pipes_orig[1]), 'w')
-                       files.ebuild = os.fdopen(master_fd, 'r')
-                       self.registered = True
-                       self.register(files.ebuild.fileno(),
-                               select.POLLIN, self._output_handler)
+                       output_handler = self._output_handler
+               else:
+                       output_handler = self._dummy_handler
+
+               os.close(slave_fd)
+               files.ebuild = os.fdopen(master_fd, 'r')
+               self.registered = True
+               self.register(files.ebuild.fileno(), select.POLLIN, output_handler)
 
        def _output_handler(self, fd, event):
                files = self.files
@@ -1980,6 +1998,27 @@ class EbuildPhase(SubProcess):
                        self.registered = False
                        self.unregister(fd)
 
+       def _dummy_handler(self, fd, event):
+               """
+               This method is mainly interested in detecting EOF, since
+               the only purpose of the pipe is to allow the scheduler to
+               monitor the process from inside a poll() loop.
+               """
+               files = self.files
+               buf = array.array('B')
+               try:
+                       buf.fromfile(files.ebuild, self._bufsize)
+               except EOFError:
+                       pass
+               if buf:
+                       pass
+               else:
+                       fd = files.ebuild.fileno()
+                       for f in files.values():
+                               f.close()
+                       self.registered = False
+                       self.unregister(fd)
+
        def _set_returncode(self, wait_retval):
                SubProcess._set_returncode(self, wait_retval)
                msg = portage._doebuild_exit_status_check(