diff options
Diffstat (limited to 'lib/backupstore/BackupStoreContext.cpp')
| -rw-r--r-- | lib/backupstore/BackupStoreContext.cpp | 94 |
1 files changed, 61 insertions, 33 deletions
diff --git a/lib/backupstore/BackupStoreContext.cpp b/lib/backupstore/BackupStoreContext.cpp index 393dc0d2..3769344b 100644 --- a/lib/backupstore/BackupStoreContext.cpp +++ b/lib/backupstore/BackupStoreContext.cpp @@ -30,13 +30,14 @@ #include "MemLeakFindOn.h" -// Maximum number of directories to keep in the cache -// When the cache is bigger than this, everything gets -// deleted. +// Maximum number of directories to keep in the cache When the cache is bigger +// than this, everything gets deleted. In tests, we set the cache size to zero +// to ensure that it's always flushed, which is very inefficient but helps to +// catch programming errors (use of freed data). #ifdef BOX_RELEASE_BUILD #define MAX_CACHE_SIZE 32 #else - #define MAX_CACHE_SIZE 2 + #define MAX_CACHE_SIZE 0 #endif // Allow the housekeeping process 4 seconds to release an account @@ -292,15 +293,21 @@ void BackupStoreContext::MakeObjectFilename(int64_t ObjectID, std::string &rOutp // -------------------------------------------------------------------------- // // Function -// Name: BackupStoreContext::GetDirectoryInternal(int64_t) -// Purpose: Return a reference to a directory. Valid only until the -// next time a function which affects directories is called. -// Mainly this funciton, and creation of files. -// Private version of this, which returns non-const directories. +// Name: BackupStoreContext::GetDirectoryInternal(int64_t, +// bool) +// Purpose: Return a reference to a directory. Valid only until +// the next time a function which affects directories +// is called. Mainly this function, and creation of +// files. Private version of this, which returns +// non-const directories. Unless called with +// AllowFlushCache == false, the cache may be flushed, +// invalidating all directory references that you may +// be holding, so beware. // Created: 2003/09/02 // // -------------------------------------------------------------------------- -BackupStoreDirectory &BackupStoreContext::GetDirectoryInternal(int64_t ObjectID) +BackupStoreDirectory &BackupStoreContext::GetDirectoryInternal(int64_t ObjectID, + bool AllowFlushCache) { // Get the filename std::string filename; @@ -309,23 +316,30 @@ BackupStoreDirectory &BackupStoreContext::GetDirectoryInternal(int64_t ObjectID) // Already in cache? std::map<int64_t, BackupStoreDirectory*>::iterator item(mDirectoryCache.find(ObjectID)); - if(item != mDirectoryCache.end()) - { - oldRevID = item->second->GetRevisionID(); - - // Check the revision ID of the file -- does it need refreshing? - if(!RaidFileRead::FileExists(mStoreDiscSet, filename, &newRevID)) - { - THROW_EXCEPTION(BackupStoreException, DirectoryHasBeenDeleted) - } - - if(newRevID == oldRevID) + if(item != mDirectoryCache.end()) { +#ifndef BOX_RELEASE_BUILD // it might be in the cache, but invalidated + // in which case, delete it instead of returning it. + if(!item->second->IsInvalidated()) +#else + if(true) +#endif { - // Looks good... return the cached object - BOX_TRACE("Returning object " << - BOX_FORMAT_OBJECTID(ObjectID) << - " from cache, modtime = " << newRevID) - return *(item->second); + oldRevID = item->second->GetRevisionID(); + + // Check the revision ID of the file -- does it need refreshing? + if(!RaidFileRead::FileExists(mStoreDiscSet, filename, &newRevID)) + { + THROW_EXCEPTION(BackupStoreException, DirectoryHasBeenDeleted) + } + + if(newRevID == oldRevID) + { + // Looks good... return the cached object + BOX_TRACE("Returning object " << + BOX_FORMAT_OBJECTID(ObjectID) << + " from cache, modtime = " << newRevID) + return *(item->second); + } } // Delete this cached object @@ -336,10 +350,22 @@ BackupStoreDirectory &BackupStoreContext::GetDirectoryInternal(int64_t ObjectID) // Need to load it up // First check to see if the cache is too big - if(mDirectoryCache.size() > MAX_CACHE_SIZE) + if(mDirectoryCache.size() > MAX_CACHE_SIZE && AllowFlushCache) { - // Very simple. Just delete everything! + // Very simple. Just delete everything! But in debug builds, + // leave the entries in the cache and invalidate them instead, + // so that any attempt to access them will cause an assertion + // failure that helps to track down the error. +#ifdef BOX_RELEASE_BUILD ClearDirectoryCache(); +#else + for(std::map<int64_t, BackupStoreDirectory*>::iterator + i = mDirectoryCache.begin(); + i != mDirectoryCache.end(); i++) + { + i->second->Invalidate(); + } +#endif } // Get a RaidFileRead to read it @@ -1022,18 +1048,20 @@ void BackupStoreContext::SaveDirectory(BackupStoreDirectory &rDir) // that it reflects the current size of the parent directory. int64_t new_dir_size = rDir.GetUserInfo1_SizeInBlocks(); if(new_dir_size != old_dir_size && - rDir.GetObjectID() != BACKUPSTORE_ROOT_DIRECTORY_ID) + ObjectID != BACKUPSTORE_ROOT_DIRECTORY_ID) { + int64_t ContainerID = rDir.GetContainerID(); BackupStoreDirectory& parent( - GetDirectoryInternal(rDir.GetContainerID())); + GetDirectoryInternal(ContainerID)); + // rDir is now invalid BackupStoreDirectory::Entry* en = - parent.FindEntryByID(rDir.GetObjectID()); + parent.FindEntryByID(ObjectID); if(!en) { BOX_ERROR("Missing entry for directory " << - BOX_FORMAT_OBJECTID(rDir.GetObjectID()) << + BOX_FORMAT_OBJECTID(ObjectID) << " in directory " << - BOX_FORMAT_OBJECTID(rDir.GetContainerID()) << + BOX_FORMAT_OBJECTID(ContainerID) << " while trying to update dir size in parent"); } else |