Adam Lesinski | 282e181 | 2014-01-23 18:17:42 -0800 | [diff] [blame^] | 1 | // |
| 2 | // Copyright 2011 The Android Open Source Project |
| 3 | // |
| 4 | // Cache manager for pre-processed PNG files. |
| 5 | // Contains code for managing which PNG files get processed |
| 6 | // at build time. |
| 7 | // |
| 8 | |
| 9 | #ifndef CRUNCHCACHE_H |
| 10 | #define CRUNCHCACHE_H |
| 11 | |
| 12 | #include <utils/KeyedVector.h> |
| 13 | #include <utils/String8.h> |
| 14 | #include "FileFinder.h" |
| 15 | #include "CacheUpdater.h" |
| 16 | |
| 17 | using namespace android; |
| 18 | |
| 19 | /** CrunchCache |
| 20 | * This class is a cache manager which can pre-process PNG files and store |
| 21 | * them in a mirror-cache. It's capable of doing incremental updates to its |
| 22 | * cache. |
| 23 | * |
| 24 | * Usage: |
| 25 | * Create an instance initialized with the root of the source tree, the |
| 26 | * root location to store the cache files, and an instance of a file finder. |
| 27 | * Then update the cache by calling crunch. |
| 28 | */ |
| 29 | class CrunchCache { |
| 30 | public: |
| 31 | // Constructor |
| 32 | CrunchCache(String8 sourcePath, String8 destPath, FileFinder* ff); |
| 33 | |
| 34 | // Nobody should be calling the default constructor |
| 35 | // So this space is intentionally left blank |
| 36 | |
| 37 | // Default Copy Constructor and Destructor are fine |
| 38 | |
| 39 | /** crunch is the workhorse of this class. |
| 40 | * It goes through all the files found in the sourcePath and compares |
| 41 | * them to the cached versions in the destPath. If the optional |
| 42 | * argument forceOverwrite is set to true, then all source files are |
| 43 | * re-crunched even if they have not been modified recently. Otherwise, |
| 44 | * source files are only crunched when they needUpdating. Afterwards, |
| 45 | * we delete any leftover files in the cache that are no longer present |
| 46 | * in source. |
| 47 | * |
| 48 | * PRECONDITIONS: |
| 49 | * No setup besides construction is needed |
| 50 | * POSTCONDITIONS: |
| 51 | * The cache is updated to fully reflect all changes in source. |
| 52 | * The function then returns the number of files changed in cache |
| 53 | * (counting deletions). |
| 54 | */ |
| 55 | size_t crunch(CacheUpdater* cu, bool forceOverwrite=false); |
| 56 | |
| 57 | private: |
| 58 | /** loadFiles is a wrapper to the FileFinder that places matching |
| 59 | * files into mSourceFiles and mDestFiles. |
| 60 | * |
| 61 | * POSTCONDITIONS |
| 62 | * mDestFiles and mSourceFiles are refreshed to reflect the current |
| 63 | * state of the files in the source and dest directories. |
| 64 | * Any previous contents of mSourceFiles and mDestFiles are cleared. |
| 65 | */ |
| 66 | void loadFiles(); |
| 67 | |
| 68 | /** needsUpdating takes a file path |
| 69 | * and returns true if the file represented by this path is newer in the |
| 70 | * sourceFiles than in the cache (mDestFiles). |
| 71 | * |
| 72 | * PRECONDITIONS: |
| 73 | * mSourceFiles and mDestFiles must be initialized and filled. |
| 74 | * POSTCONDITIONS: |
| 75 | * returns true if and only if source file's modification time |
| 76 | * is greater than the cached file's mod-time. Otherwise returns false. |
| 77 | * |
| 78 | * USAGE: |
| 79 | * Should be used something like the following: |
| 80 | * if (needsUpdating(filePath)) |
| 81 | * // Recrunch sourceFile out to destFile. |
| 82 | * |
| 83 | */ |
| 84 | bool needsUpdating(String8 relativePath) const; |
| 85 | |
| 86 | // DATA MEMBERS ==================================================== |
| 87 | |
| 88 | String8 mSourcePath; |
| 89 | String8 mDestPath; |
| 90 | |
| 91 | Vector<String8> mExtensions; |
| 92 | |
| 93 | // Each vector of paths contains one entry per PNG file encountered. |
| 94 | // Each entry consists of a path pointing to that PNG. |
| 95 | DefaultKeyedVector<String8,time_t> mSourceFiles; |
| 96 | DefaultKeyedVector<String8,time_t> mDestFiles; |
| 97 | |
| 98 | // Pointer to a FileFinder to use |
| 99 | FileFinder* mFileFinder; |
| 100 | }; |
| 101 | |
| 102 | #endif // CRUNCHCACHE_H |