1 files changed, 97 insertions, 0 deletions
diff --git a/buildtools/wafadmin/3rdparty/lru_cache.py b/buildtools/wafadmin/3rdparty/lru_cache.py
new file mode 100644
index 0000000000..5b00abc29b
--- /dev/null
+++ b/buildtools/wafadmin/3rdparty/lru_cache.py
@@ -0,0 +1,97 @@
+#! /usr/bin/env python
+# encoding: utf-8
+# Thomas Nagy 2011
+
+import os, shutil, re
+import Options, Build, Logs
+
+"""
+Apply a least recently used policy to the Waf cache.
+
+For performance reasons, it is called after the build is complete.
+
+We assume that the the folders are written atomically
+
+Do export WAFCACHE=/tmp/foo-xyz where xyz represents the cache size in megabytes
+If missing, the default cache size will be set to 10GB
+"""
+
+re_num = re.compile('[a-zA-Z_]+(\d+)')
+
+CACHESIZE = 10*1024*1024*1024 # in bytes
+CLEANRATIO = 0.8
+DIRSIZE = 4096
+
+def compile(self):
+	if Options.cache_global and not Options.options.nocache:
+		try:
+			os.makedirs(Options.cache_global)
+		except:
+			pass
+
+	try:
+		self.raw_compile()
+	finally:
+		if Options.cache_global and not Options.options.nocache:
+			self.sweep()
+
+def sweep(self):
+	global CACHESIZE
+	CACHEDIR = Options.cache_global
+
+	# get the cache max size from the WAFCACHE filename
+	re_num = re.compile('[a-zA-Z_]+(\d+)')
+	val = re_num.sub('\\1', os.path.basename(Options.cache_global))
+	try:
+		CACHESIZE = int(val)
+	except:
+		pass
+
+	# map folder names to timestamps
+	flist = {}
+	for x in os.listdir(CACHEDIR):
+		j = os.path.join(CACHEDIR, x)
+		if os.path.isdir(j) and len(x) == 32: # dir names are md5 hexdigests
+			flist[x] = [os.stat(j).st_mtime, 0]
+
+	for (x, v) in flist.items():
+		cnt = DIRSIZE # each entry takes 4kB
+		d = os.path.join(CACHEDIR, x)
+		for k in os.listdir(d):
+			cnt += os.stat(os.path.join(d, k)).st_size
+		flist[x][1] = cnt
+
+	total = sum([x[1] for x in flist.values()])
+	Logs.debug('lru: Cache size is %r' % total)
+
+	if total >= CACHESIZE:
+		Logs.debug('lru: Trimming the cache since %r > %r' % (total, CACHESIZE))
+
+		# make a list to sort the folders by timestamp
+		lst = [(p, v[0], v[1]) for (p, v) in flist.items()]
+		lst.sort(key=lambda x: x[1]) # sort by timestamp
+		lst.reverse()
+
+		while total >= CACHESIZE * CLEANRATIO:
+			(k, t, s) = lst.pop()
+			p = os.path.join(CACHEDIR, k)
+			v = p + '.del'
+			try:
+				os.rename(p, v)
+			except:
+				# someone already did it
+				pass
+			else:
+				try:
+					shutil.rmtree(v)
+				except:
+					# this should not happen, but who knows?
+					Logs.warn('If you ever see this message, report it (%r)' % v)
+			total -= s
+			del flist[k]
+	Logs.debug('lru: Total at the end %r' % total)
+
+Build.BuildContext.raw_compile = Build.BuildContext.compile
+Build.BuildContext.compile = compile
+Build.BuildContext.sweep = sweep
+