Added Caching for PreProcessed PNGs
Added a cache management system for pre-processed PNG files
along with unit tests. The cache system will be used if
the --no-crunch flag is passed to AAPT during the package
phase. The cache can be updated by a call to 'aapt crunch'
(see usage statement). Also put in benchmarking code.
Change-Id: I58271fb2ee2f5f9075fd74d4ff6f15e7afabd05c
diff --git a/tools/aapt/CrunchCache.cpp b/tools/aapt/CrunchCache.cpp
new file mode 100644
index 0000000..c4cf6bc
--- /dev/null
+++ b/tools/aapt/CrunchCache.cpp
@@ -0,0 +1,104 @@
+//
+// Copyright 2011 The Android Open Source Project
+//
+// Implementation file for CrunchCache
+// This file defines functions laid out and documented in
+// CrunchCache.h
+
+#include <utils/Vector.h>
+#include <utils/String8.h>
+
+#include "DirectoryWalker.h"
+#include "FileFinder.h"
+#include "CacheUpdater.h"
+#include "CrunchCache.h"
+
+using namespace android;
+
+CrunchCache::CrunchCache(String8 sourcePath, String8 destPath, FileFinder* ff)
+ : mSourcePath(sourcePath), mDestPath(destPath), mSourceFiles(0), mDestFiles(0), mFileFinder(ff)
+{
+ // We initialize the default value to return to 0 so if a file doesn't exist
+ // then all files are automatically "newer" than it.
+
+ // Set file extensions to look for. Right now just pngs.
+ mExtensions.push(String8(".png"));
+
+ // Load files into our data members
+ loadFiles();
+}
+
+size_t CrunchCache::crunch(CacheUpdater* cu, bool forceOverwrite)
+{
+ size_t numFilesUpdated = 0;
+
+ // Iterate through the source files and compare to cache.
+ // After processing a file, remove it from the source files and
+ // from the dest files.
+ // We're done when we're out of files in source.
+ String8 relativePath;
+ while (mSourceFiles.size() > 0) {
+ // Get the full path to the source file, then convert to a c-string
+ // and offset our beginning pointer to the length of the sourcePath
+ // This efficiently strips the source directory prefix from our path.
+ // Also, String8 doesn't have a substring method so this is what we've
+ // got to work with.
+ const char* rPathPtr = mSourceFiles.keyAt(0).string()+mSourcePath.length();
+ // Strip leading slash if present
+ int offset = 0;
+ if (rPathPtr[0] == OS_PATH_SEPARATOR)
+ offset = 1;
+ relativePath = String8(rPathPtr + offset);
+
+ if (forceOverwrite || needsUpdating(relativePath)) {
+ cu->processImage(mSourcePath.appendPathCopy(relativePath),
+ mDestPath.appendPathCopy(relativePath));
+ numFilesUpdated++;
+ // crunchFile(relativePath);
+ }
+ // Delete this file from the source files and (if it exists) from the
+ // dest files.
+ mSourceFiles.removeItemsAt(0);
+ mDestFiles.removeItem(mDestPath.appendPathCopy(relativePath));
+ }
+
+ // Iterate through what's left of destFiles and delete leftovers
+ while (mDestFiles.size() > 0) {
+ cu->deleteFile(mDestFiles.keyAt(0));
+ mDestFiles.removeItemsAt(0);
+ }
+
+ // Update our knowledge of the files cache
+ // both source and dest should be empty by now.
+ loadFiles();
+
+ return numFilesUpdated;
+}
+
+void CrunchCache::loadFiles()
+{
+ // Clear out our data structures to avoid putting in duplicates
+ mSourceFiles.clear();
+ mDestFiles.clear();
+
+ // Make a directory walker that points to the system.
+ DirectoryWalker* dw = new SystemDirectoryWalker();
+
+ // Load files in the source directory
+ mFileFinder->findFiles(mSourcePath, mExtensions, mSourceFiles,dw);
+
+ // Load files in the destination directory
+ mFileFinder->findFiles(mDestPath,mExtensions,mDestFiles,dw);
+
+ delete dw;
+}
+
+bool CrunchCache::needsUpdating(String8 relativePath) const
+{
+ // Retrieve modification dates for this file entry under the source and
+ // cache directory trees. The vectors will return a modification date of 0
+ // if the file doesn't exist.
+ time_t sourceDate = mSourceFiles.valueFor(mSourcePath.appendPathCopy(relativePath));
+ time_t destDate = mDestFiles.valueFor(mDestPath.appendPathCopy(relativePath));
+ return sourceDate > destDate;
+}
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