Use a fake vartree for depgraph calculations. This minimizes the time that a lock...

svn path=/main/trunk/; revision=5189

diff --git a/bin/emerge b/bin/emerge
index a4e29e9c6a8043767a88e3a33c3868dc39b9fec4..7040e0913c164f6edfc221e94aa38ff74d3a448a 100755 (executable)
--- a/bin/emerge
+++ b/bin/emerge
@@ -699,6 +699,34 @@ class DepPriority(object):
                        return "medium"
                return "soft"
 
+class FakeVartree(object):
+       """This is implements an in-memory copy of a vartree instance that provides
+       all the interfaces required for use by the depgraph.  The vardb is locked
+       during the constructor call just long enough to read a copy of the
+       installed package information.  This allows the depgraph to do it's
+       dependency calculations without holding a lock on the vardb.  It also
+       allows things like vardb global updates to be done in memory so that the
+       user doesn't necessarily need write access to the vardb in cases where
+       global updates are necessary (updates are performed when necessary if there
+       is not a matching ebuild in the tree)."""
+       def __init__(self, real_vartree):
+               self.root = real_vartree.root
+               self.settings = real_vartree.settings
+               self.dbapi = portage.fakedbapi(settings=real_vartree.settings)
+               vdb_path = os.path.join(self.root, portage.VDB_PATH)
+               vdb_lock = None
+               try:
+                       if os.access(vdb_path, os.W_OK):
+                               vdb_lock = portage_locks.lockdir(vdb_path)
+                       mykeys = ["SLOT", "USE", "IUSE", "DEPEND", "RDEPEND", "PDEPEND"]
+                       real_dbapi = real_vartree.dbapi
+                       for cpv in real_dbapi.cpv_all():
+                               metadata = dict(zip(mykeys, real_dbapi.aux_get(cpv, mykeys)))
+                               self.dbapi.cpv_inject(cpv, metadata=metadata)
+               finally:
+                       if vdb_lock:
+                               portage_locks.unlockdir(vdb_lock)
+
 class depgraph:
 
        pkg_tree_map = {
@@ -709,7 +737,6 @@ class depgraph:
        def __init__(self, settings, trees, myopts, myparams, spinner):
                self.settings = settings
                self.target_root = settings["ROOT"]
-               self.trees = trees
                self.myopts = myopts
                self.myparams = myparams
                self.edebug = 0
@@ -718,10 +745,17 @@ class depgraph:
                self.spinner = spinner
                self.pkgsettings = {}
                self.pkg_node_map = {}
-               for myroot in self.trees:
+               self.trees = {}
+               for myroot in trees:
+                       self.trees[myroot] = {}
+                       for tree in ("porttree", "bintree"):
+                               self.trees[myroot][tree] = trees[myroot][tree]
+                       self.trees[myroot]["vartree"] = \
+                               FakeVartree(trees[myroot]["vartree"])
                        self.pkgsettings[myroot] = portage.config(
-                               clone=trees[myroot]["vartree"].settings)
+                               clone=self.trees[myroot]["vartree"].settings)
                        self.pkg_node_map[myroot] = {}
+               del trees
                self.useFlags = {}
                self.useFlags[self.target_root] = {}
                if self.target_root != "/":
@@ -749,10 +783,10 @@ class depgraph:
                                        myslot = vardb.aux_get(pkg, ["SLOT"])[0]
                                        fakedb.cpv_inject(pkg, metadata={"SLOT":myslot})
                if "--usepkg" in self.myopts:
-                       trees["/"]["bintree"].populate(
+                       self.trees["/"]["bintree"].populate(
                                "--getbinpkg" in self.myopts, "--getbinpkgonly" in self.myopts)
                        if self.target_root != "/":
-                               trees[self.target_root]["bintree"].populate(
+                               self.trees[self.target_root]["bintree"].populate(
                                        "--getbinpkg" in self.myopts,
                                        "--getbinpkgonly" in self.myopts)
                self.args_keys = []