[gnome-continuous-yocto/gnomeostree-3.28-rocko: 2466/8267] oeqa/utils/decorators: LogResults fix race condition in linkfile

[Emmanuele Bassi <ebassi src gnome org>]

commit 62c45ffbc7c239b6d50931a0fc46f9a67635b1b1
Author: Aníbal Limón <anibal limon linux intel com>
Date:   Tue Sep 13 15:25:42 2016 -0500

    oeqa/utils/decorators: LogResults fix race condition in linkfile
    
    In order to avoid race condition when test if exists the linkfile
    use bb.utils.lock, the best solution is to create a unique name
    for the link file.
    
    There is no way to create a unique linkfile name at this decorator
    because is needed the machine and image variables, those variables
    can't be passed easily in this code.
    
    To avoid broke test export functionality use a try/except because bb
    isn't available when use test export
    
    [YOCTO #10225]
    
    (From OE-Core rev: 059d475b6bce1e5414170a4fe2e7989f6b0eacd6)
    
    Signed-off-by: Aníbal Limón <anibal limon linux intel com>
    Signed-off-by: Richard Purdie <richard purdie linuxfoundation org>

 meta/lib/oeqa/utils/decorators.py |   14 ++++++++++++++
 1 files changed, 14 insertions(+), 0 deletions(-)
---
diff --git a/meta/lib/oeqa/utils/decorators.py b/meta/lib/oeqa/utils/decorators.py
index 615fd95..25f9c54 100644
--- a/meta/lib/oeqa/utils/decorators.py
+++ b/meta/lib/oeqa/utils/decorators.py
@@ -189,10 +189,24 @@ def LogResults(original_class):
         if passed:
             local_log.results("Testcase "+str(test_case)+": PASSED")
 
+        # XXX: In order to avoid race condition when test if exists the linkfile
+        # use bb.utils.lock, the best solution is to create a unique name for the
+        # link file.
+        try:
+            import bb
+            has_bb = True
+            lockfilename = linkfile + '.lock'
+        except ImportError:
+            has_bb = False
+
+        if has_bb:
+            lf = bb.utils.lockfile(lockfilename, block=True)
         # Create symlink to the current log
         if os.path.lexists(linkfile):
             os.remove(linkfile)
         os.symlink(logfile, linkfile)
+        if has_bb:
+            bb.utils.unlockfile(lf)
 
     original_class.run = run