Merge package files in a subprocess.

This allows the Scheduler to run in the main thread while files are
moved or copied asynchronously.

diff --git a/pym/portage/dbapi/_MergeProcess.py b/pym/portage/dbapi/_MergeProcess.py
new file mode 100644 (file)
index 0000000..b5af714
--- /dev/null
+++ b/pym/portage/dbapi/_MergeProcess.py
@@ -0,0 +1,41 @@
+# Copyright 2010 Gentoo Foundation
+# Distributed under the terms of the GNU General Public License v2
+
+import portage
+from portage import os
+from _emerge.SpawnProcess import SpawnProcess
+
+class MergeProcess(SpawnProcess):
+       """
+       Merge package files in a subprocess, so the Scheduler can run in the
+       main thread while files are moved or copied asynchronously.
+       """
+
+       __slots__ = ('cfgfiledict', 'conf_mem_file', \
+               'destroot', 'dblink', 'srcroot',)
+
+       def _spawn(self, args, fd_pipes=None, **kwargs):
+               """
+               Fork a subprocess, apply local settings, and call
+               dblink._merge_process().
+               """
+
+               pid = os.fork()
+               if pid != 0:
+                       portage.process.spawned_pids.append(pid)
+                       return [pid]
+
+               portage.process._setup_pipes(fd_pipes)
+
+               portage.output.havecolor = self.dblink.settings.get('NOCOLOR') \
+                       not in ('yes', 'true')
+
+               # In this subprocess we want dblink._display_merge() to use
+               # stdout/stderr directly since they are pipes. This behavior
+               # is triggered when dblink._scheduler is None.
+               self.dblink._scheduler = None
+
+               rval = self.dblink._merge_process(self.srcroot, self.destroot,
+                       self.cfgfiledict, self.conf_mem_file)
+
+               os._exit(rval)

diff --git a/pym/portage/dbapi/vartree.py b/pym/portage/dbapi/vartree.py
index 89fdca09277667acd495c8cdd719d426dbb5e3d3..68968fe64e4b6d13f175b905894bcc8ffcb53153 100644 (file)
--- a/pym/portage/dbapi/vartree.py
+++ b/pym/portage/dbapi/vartree.py
@@ -10,6 +10,7 @@ portage.proxy.lazyimport.lazyimport(globals(),
        'portage.checksum:_perform_md5_merge@perform_md5',
        'portage.data:portage_gid,portage_uid,secpass',
        'portage.dbapi.dep_expand:dep_expand',
+       'portage.dbapi._MergeProcess:MergeProcess',
        'portage.dep:dep_getkey,isjustname,match_from_list,' + \
                'use_reduce,_slot_re',
        'portage.elog:elog_process,_preload_elog_modules',
@@ -3182,19 +3183,11 @@ class dblink(object):
                        'w', encoding=_encodings['repo.content'], errors='backslashreplace'
                        ).write(str(counter))
 
-               # open CONTENTS file (possibly overwriting old one) for recording
-               outfile = codecs.open(_unicode_encode(
-                       os.path.join(self.dbtmpdir, 'CONTENTS'),
-                       encoding=_encodings['fs'], errors='strict'),
-                       mode='w', encoding=_encodings['repo.content'],
-                       errors='backslashreplace')
-
                self.updateprotect()
 
                #if we have a file containing previously-merged config file md5sums, grab it.
                conf_mem_file = os.path.join(self._eroot, CONFIG_MEMORY_FILE)
                cfgfiledict = grabdict(conf_mem_file)
-               cfgfiledict_orig = cfgfiledict.copy()
                if "NOCONFMEM" in self.settings:
                        cfgfiledict["IGNORE"]=1
                else:
@@ -3209,61 +3202,18 @@ class dblink(object):
                                cfgfiledict["IGNORE"] = 1
                                break
 
-               # Don't bump mtimes on merge since some application require
-               # preservation of timestamps.  This means that the unmerge phase must
-               # check to see if file belongs to an installed instance in the same
-               # slot.
-               mymtime = None
-
-               # set umask to 0 for merging; back up umask, save old one in prevmask (since this is a global change)
-               prevmask = os.umask(0)
-               secondhand = []
-
-               # we do a first merge; this will recurse through all files in our srcroot but also build up a
-               # "second hand" of symlinks to merge later
-               if self.mergeme(srcroot, destroot, outfile, secondhand, "", cfgfiledict, mymtime):
-                       return 1
-
-               # now, it's time for dealing our second hand; we'll loop until we can't merge anymore.  The rest are
-               # broken symlinks.  We'll merge them too.
-               lastlen = 0
-               while len(secondhand) and len(secondhand)!=lastlen:
-                       # clear the thirdhand.  Anything from our second hand that
-                       # couldn't get merged will be added to thirdhand.
-
-                       thirdhand = []
-                       if self.mergeme(srcroot, destroot, outfile, thirdhand,
-                               secondhand, cfgfiledict, mymtime):
-                               return 1
-
-                       #swap hands
-                       lastlen = len(secondhand)
-
-                       # our thirdhand now becomes our secondhand.  It's ok to throw
-                       # away secondhand since thirdhand contains all the stuff that
-                       # couldn't be merged.
-                       secondhand = thirdhand
+               merge_task = MergeProcess(
+                       background=(self.settings.get('PORTAGE_BACKGROUND') == '1'),
+                       cfgfiledict=cfgfiledict, conf_mem_file=conf_mem_file, dblink=self,
+                       destroot=destroot,
+                       logfile=self.settings.get('PORTAGE_LOG_FILE'),
+                       scheduler=(scheduler or PollScheduler().sched_iface),
+                       srcroot=srcroot)
 
-               if len(secondhand):
-                       # force merge of remaining symlinks (broken or circular; oh well)
-                       if self.mergeme(srcroot, destroot, outfile, None,
-                               secondhand, cfgfiledict, mymtime):
-                               return 1
-               self._md5_merge_map.clear()
-
-               #restore umask
-               os.umask(prevmask)
-
-               #if we opened it, close it
-               outfile.flush()
-               outfile.close()
-
-               # write out our collection of md5sums
-               cfgfiledict.pop("IGNORE", None)
-               if cfgfiledict != cfgfiledict_orig:
-                       ensure_dirs(os.path.dirname(conf_mem_file),
-                               gid=portage_gid, mode=0o2750, mask=0o2)
-                       writedict(cfgfiledict, conf_mem_file)
+               merge_task.start()
+               rval = merge_task.wait()
+               if rval != os.EX_OK:
+                       return rval
 
                # These caches are populated during collision-protect and the data
                # they contain is now invalid. It's very important to invalidate
@@ -3448,6 +3398,74 @@ class dblink(object):
 
                return backup_p
 
+       def _merge_process(self, srcroot, destroot, cfgfiledict, conf_mem_file):
+
+               cfgfiledict_orig = cfgfiledict.copy()
+
+               # open CONTENTS file (possibly overwriting old one) for recording
+               outfile = codecs.open(_unicode_encode(
+                       os.path.join(self.dbtmpdir, 'CONTENTS'),
+                       encoding=_encodings['fs'], errors='strict'),
+                       mode='w', encoding=_encodings['repo.content'],
+                       errors='backslashreplace')
+
+               # Don't bump mtimes on merge since some application require
+               # preservation of timestamps.  This means that the unmerge phase must
+               # check to see if file belongs to an installed instance in the same
+               # slot.
+               mymtime = None
+
+               # set umask to 0 for merging; back up umask, save old one in prevmask (since this is a global change)
+               prevmask = os.umask(0)
+               secondhand = []
+
+               # we do a first merge; this will recurse through all files in our srcroot but also build up a
+               # "second hand" of symlinks to merge later
+               if self.mergeme(srcroot, destroot, outfile, secondhand, "", cfgfiledict, mymtime):
+                       return 1
+
+               # now, it's time for dealing our second hand; we'll loop until we can't merge anymore.  The rest are
+               # broken symlinks.  We'll merge them too.
+               lastlen = 0
+               while len(secondhand) and len(secondhand)!=lastlen:
+                       # clear the thirdhand.  Anything from our second hand that
+                       # couldn't get merged will be added to thirdhand.
+
+                       thirdhand = []
+                       if self.mergeme(srcroot, destroot, outfile, thirdhand,
+                               secondhand, cfgfiledict, mymtime):
+                               return 1
+
+                       #swap hands
+                       lastlen = len(secondhand)
+
+                       # our thirdhand now becomes our secondhand.  It's ok to throw
+                       # away secondhand since thirdhand contains all the stuff that
+                       # couldn't be merged.
+                       secondhand = thirdhand
+
+               if len(secondhand):
+                       # force merge of remaining symlinks (broken or circular; oh well)
+                       if self.mergeme(srcroot, destroot, outfile, None,
+                               secondhand, cfgfiledict, mymtime):
+                               return 1
+
+               #restore umask
+               os.umask(prevmask)
+
+               #if we opened it, close it
+               outfile.flush()
+               outfile.close()
+
+               # write out our collection of md5sums
+               if cfgfiledict != cfgfiledict_orig:
+                       cfgfiledict.pop("IGNORE", None)
+                       ensure_dirs(os.path.dirname(conf_mem_file),
+                               gid=portage_gid, mode=0o2750, mask=0o2)
+                       writedict(cfgfiledict, conf_mem_file)
+
+               return os.EX_OK
+
        def mergeme(self, srcroot, destroot, outfile, secondhand, stufftomerge, cfgfiledict, thismtime):
                """
                
@@ -3478,7 +3496,6 @@ class dblink(object):
 
                showMessage = self._display_merge
                writemsg = self._display_merge
-               scheduler = self._scheduler
 
                os = _os_merge
                sep = os.sep
@@ -3498,10 +3515,6 @@ class dblink(object):
 
                for i, x in enumerate(mergelist):
 
-                       if scheduler is not None and \
-                               0 == i % self._file_merge_yield_interval:
-                               scheduler.scheduleYield()
-
                        mysrc = join(srcroot, offset, x)
                        mydest = join(destroot, offset, x)
                        # myrealdest is mydest without the $ROOT prefix (makes a difference if ROOT!="/")