[bitbake-devel] [PATCH 02/16] cache: Add SimpleCache class
Richard Purdie
richard.purdie at linuxfoundation.org
Fri Aug 2 15:20:35 UTC 2019
This adds a simple version of the MultiProcessCache which can be used to
save and load cache data, useful for a new usecase we have in
sigdata/runqueue.
Signed-off-by: Richard Purdie <richard.purdie at linuxfoundation.org>
---
lib/bb/cache.py | 53 +++++++++++++++++++++++++++++++++++++++++++++++++
1 file changed, 53 insertions(+)
diff --git a/lib/bb/cache.py b/lib/bb/cache.py
index ab18dd5eaa..233f994279 100644
--- a/lib/bb/cache.py
+++ b/lib/bb/cache.py
@@ -883,3 +883,56 @@ class MultiProcessCache(object):
p.dump([data, self.__class__.CACHE_VERSION])
bb.utils.unlockfile(glf)
+
+
+class SimpleCache(object):
+ """
+ BitBake multi-process cache implementation
+
+ Used by the codeparser & file checksum caches
+ """
+
+ def __init__(self, version):
+ self.cachefile = None
+ self.cachedata = None
+ self.cacheversion = version
+
+ def init_cache(self, d, cache_file_name=None, defaultdata=None):
+ cachedir = (d.getVar("PERSISTENT_DIR") or
+ d.getVar("CACHE"))
+ if not cachedir:
+ return defaultdata
+
+ bb.utils.mkdirhier(cachedir)
+ self.cachefile = os.path.join(cachedir,
+ cache_file_name or self.__class__.cache_file_name)
+ logger.debug(1, "Using cache in '%s'", self.cachefile)
+
+ glf = bb.utils.lockfile(self.cachefile + ".lock")
+
+ try:
+ with open(self.cachefile, "rb") as f:
+ p = pickle.Unpickler(f)
+ data, version = p.load()
+ except:
+ bb.utils.unlockfile(glf)
+ return defaultdata
+
+ bb.utils.unlockfile(glf)
+
+ if version != self.cacheversion:
+ return defaultdata
+
+ return data
+
+ def save(self, data):
+ if not self.cachefile:
+ return
+
+ glf = bb.utils.lockfile(self.cachefile + ".lock")
+
+ with open(self.cachefile, "wb") as f:
+ p = pickle.Pickler(f, -1)
+ p.dump([data, self.cacheversion])
+
+ bb.utils.unlockfile(glf)
--
2.20.1
More information about the bitbake-devel
mailing list