From d477e79342d015291871a69779bb089d58388c43 Mon Sep 17 00:00:00 2001
From: Will Woods <wwoods@redhat.com>
Date: Mon, 23 Feb 2009 16:29:28 -0500
Subject: Add warn_on_collision to mkdebuginfolinks and make unpack_rpm
 atomically create the target dir

---
 debuginfofs-mirror | 54 ++++++++++++++++++++++++++++++------------------------
 1 file changed, 30 insertions(+), 24 deletions(-)

diff --git a/debuginfofs-mirror b/debuginfofs-mirror
index f9ed607..b6ff618 100755
--- a/debuginfofs-mirror
+++ b/debuginfofs-mirror
@@ -135,33 +135,36 @@ def fix_perms(targetdir):
                 mode = os.stat(i)[0]
                 os.chmod(i, mode | 0444)
 
-def unpack_rpm(rpm, targetdir):
-    created_dir = False
+def _unpack_rpm(rpm, targetdir):
+    '''Unpack the given rpm into the given directory'''
     if not os.path.isdir(targetdir):
-        os.makedirs(targetdir)
-        created_dir = True
+        os.makedirs(targetdir,mode=0755)
+    os.chdir(targetdir)
+    # rpm2cpio $rpm | cpio --quiet -iumd
+    p1 = Popen(['rpm2cpio',rpm], stdout=PIPE)
+    p2 = Popen(['cpio','--quiet','-iumd'], stdin=p1.stdout, stdout=PIPE)
+    output = p2.communicate()[0] # should be empty
+    if p2.returncode != 0:
+        raise OSError, "cpio failed: %s output:\n%s" % (str(p2.returncode),output)
+    # Fix perms so all files are readable
+    fix_perms(targetdir)
 
+def unpack_rpm(rpm, targetdir):
+    '''Unpack the given rpm into a temporary directory alongside the targetdir,
+    then rename the temp dir once finished.'''
+    tmpdir = tempfile.mkdtemp(dir=os.path.dirname(targetdir))
     try:
-        # FIXME: unpack into a tmpdir and then move into place after finishing
-        # or else interrupted unpacks will leave us with incomplete output
-        os.chdir(targetdir)
-        # rpm2cpio $rpm | cpio --quiet -iumd
-        p1 = Popen(['rpm2cpio',rpm], stdout=PIPE)
-        p2 = Popen(['cpio','--quiet','-iumd'], stdin=p1.stdout, stdout=PIPE)
-        output = p2.communicate()[0] # should be empty
-        if p2.returncode != 0:
-            raise OSError, "cpio failed: %s output:\n%s" % (str(p2.returncode),output)
-        # Fix perms so all files are readable
-        fix_perms(targetdir)
-    except (IOError, OSError), e:
-        print str(e)
-        if created_dir:
-            print "removing %s" % targetdir
+        _unpack_rpm(rpm, tmpdir)
+        if os.path.isdir(targetdir):
             shutil.rmtree(targetdir)
+        os.rename(tmpdir,targetdir)
+        return True
+    except (OSError, IOError), e:
+        print "unpack_rpm failed: %s" % str(e)
+        shutil.rmtree(tmpdir)
         return False
-    return True
 
-def mkdebuginfolinks(sourcedir, targetdir):
+def mkdebuginfolinks(sourcedir, targetdir, warn_on_collision=False):
     '''hardlink debuginfo from sourcedir into targetdir'''
     count = 0
     for top, dirs, files in os.walk(sourcedir, topdown=True):
@@ -172,13 +175,15 @@ def mkdebuginfolinks(sourcedir, targetdir):
             linkname = u.split('/usr/lib/debug/.build-id/')[1]
             newlink = os.path.join(targetdir,linkname)
             try:
-                os.makedirs(os.path.dirname(newlink))
+                os.makedirs(os.path.dirname(newlink),mode=0755)
             except OSError, e:
                 if e.errno != 17:
                     raise e
             if os.path.exists(newlink):
-                # TODO: check to see if the contents of target == newlink
-                # If not, we have a collision. That's bad.
+                if warn_on_collision and (os.stat(newlink) != os.stat(target)):
+                    # TODO: better logging here
+                    print "WARNING: collision or damaged debuginfo detected"
+                    print "%s exists - removing" % (newlink,)
                 os.unlink(newlink)
             os.link(target,newlink)
             count += 1
@@ -238,6 +243,7 @@ def main():
             repo.cachedir = repo.id
             y.repos.add(repo)
             y.repos.doSetup(thisrepo=repo.id)
+    # FIXME: locking - don't setup a repo that's in use by another process
 
     repolist = y.repos.listEnabled()
     if repolist:
-- 
cgit