From d07a4868a11a282acafa4cefcf3cac53da82277d Mon Sep 17 00:00:00 2001 From: Vincent Povirk Date: Wed, 5 May 2010 14:23:12 -0500 Subject: [PATCH] ole32: Rewrite transacted storage to be more lazy. When creating a new transacted storage object (or reverting an existing one), rather than copy the original storage, we simply create a "stub directory entry" for the root. As stub entries are accessed, we fill in their data from the parent and create new stubs for any linked entries. The streams have copy on write semantics - reads are from the original entry until a change is made, then we make a copy in the scratch file. When committing transacted storages, we have to create a new tree with the new data so that the storage entry can be modified in one step, but unmodified sections of the tree can now be shared between the new tree and the old. An entry can be shared if it and all entries reachable from it are unmodified. In the trivial case where nothing has been modified, we don't have to make a new tree at all. --- dlls/ole32/storage32.c | 796 +++++++++++++++++++++++++++++++++-------- 1 file changed, 648 insertions(+), 148 deletions(-) diff --git a/dlls/ole32/storage32.c b/dlls/ole32/storage32.c index 22d33b1566e..a9354c9bb33 100644 --- a/dlls/ole32/storage32.c +++ b/dlls/ole32/storage32.c @@ -118,17 +118,61 @@ static BOOL StorageImpl_ReadDWordFromBigBlock( StorageImpl* This, static BOOL StorageBaseImpl_IsStreamOpen(StorageBaseImpl * stg, DirRef streamEntry); static BOOL StorageBaseImpl_IsStorageOpen(StorageBaseImpl * stg, DirRef storageEntry); +typedef struct TransactedDirEntry +{ + /* If applicable, a reference to the original DirEntry in the transacted + * parent. If this is a newly-created entry, DIRENTRY_NULL. */ + DirRef transactedParentEntry; + + /* True if this entry is being used. */ + int inuse; + + /* True if data is up to date. */ + int read; + + /* True if this entry has been modified. */ + int dirty; + + /* True if this entry's stream has been modified. */ + int stream_dirty; + + /* True if this entry has been deleted in the transacted storage, but the + * delete has not yet been committed. */ + int deleted; + + /* If this entry's stream has been modified, a reference to where the stream + * is stored in the snapshot file. */ + DirRef stream_entry; + + /* This directory entry's data, including any changes that have been made. */ + DirEntry data; + + /* A reference to the parent of this node. This is only valid while we are + * committing changes. */ + DirRef parent; + + /* A reference to a newly-created entry in the transacted parent. This is + * always equal to transactedParentEntry except when committing changes. */ + DirRef newTransactedParentEntry; +} TransactedDirEntry; + /**************************************************************************** - * Transacted storage object that reads/writes a snapshot file. + * Transacted storage object. */ typedef struct TransactedSnapshotImpl { struct StorageBaseImpl base; /* - * Changes are temporarily saved to the snapshot. + * Modified streams are temporarily saved to the scratch file. */ - StorageBaseImpl *snapshot; + StorageBaseImpl *scratch; + + /* The directory structure is kept here, so that we can track how these + * entries relate to those in the parent storage. */ + TransactedDirEntry *entries; + ULONG entries_size; + ULONG firstFreeEntry; /* * Changes are committed to the transacted parent. @@ -1296,46 +1340,6 @@ static HRESULT StorageImpl_DestroyDirEntry( } -/*************************************************************************** - * - * Internal Method - * - * Destroy an entry, its attached data, and all entries reachable from it. - */ -static HRESULT DestroyReachableEntries( - StorageBaseImpl *base, - DirRef index) -{ - HRESULT hr = S_OK; - DirEntry data; - ULARGE_INTEGER zero; - - zero.QuadPart = 0; - - if (index != DIRENTRY_NULL) - { - hr = StorageBaseImpl_ReadDirEntry(base, index, &data); - - if (SUCCEEDED(hr)) - hr = DestroyReachableEntries(base, data.dirRootEntry); - - if (SUCCEEDED(hr)) - hr = DestroyReachableEntries(base, data.leftChild); - - if (SUCCEEDED(hr)) - hr = DestroyReachableEntries(base, data.rightChild); - - if (SUCCEEDED(hr)) - hr = StorageBaseImpl_StreamSetSize(base, index, zero); - - if (SUCCEEDED(hr)) - hr = StorageBaseImpl_DestroyDirEntry(base, index); - } - - return hr; -} - - /**************************************************************************** * * Internal Method @@ -4011,40 +4015,370 @@ SmallBlockChainStream* Storage32Impl_BigBlocksToSmallBlocks( return SmallBlockChainStream_Construct(This, NULL, streamEntryRef); } -static HRESULT CreateSnapshotFile(StorageBaseImpl* original, StorageBaseImpl **snapshot) +static HRESULT StorageBaseImpl_CopyStream( + StorageBaseImpl *dst, DirRef dst_entry, + StorageBaseImpl *src, DirRef src_entry) { HRESULT hr; - DirEntry parentData, snapshotData; + BYTE data[4096]; + DirEntry srcdata; + ULARGE_INTEGER bytes_copied; + ULONG bytestocopy, bytesread, byteswritten; - hr = StgCreateDocfile(NULL, STGM_READWRITE|STGM_SHARE_EXCLUSIVE|STGM_DELETEONRELEASE, - 0, (IStorage**)snapshot); + hr = StorageBaseImpl_ReadDirEntry(src, src_entry, &srcdata); if (SUCCEEDED(hr)) { - hr = StorageBaseImpl_ReadDirEntry(original, - original->storageDirEntry, &parentData); + hr = StorageBaseImpl_StreamSetSize(dst, dst_entry, srcdata.size); - if (SUCCEEDED(hr)) - hr = StorageBaseImpl_ReadDirEntry((*snapshot), - (*snapshot)->storageDirEntry, &snapshotData); - - if (SUCCEEDED(hr)) + bytes_copied.QuadPart = 0; + while (bytes_copied.QuadPart < srcdata.size.QuadPart && SUCCEEDED(hr)) { - memcpy(snapshotData.name, parentData.name, sizeof(snapshotData.name)); - snapshotData.sizeOfNameString = parentData.sizeOfNameString; - snapshotData.stgType = parentData.stgType; - snapshotData.clsid = parentData.clsid; - snapshotData.ctime = parentData.ctime; - snapshotData.mtime = parentData.mtime; - hr = StorageBaseImpl_WriteDirEntry((*snapshot), - (*snapshot)->storageDirEntry, &snapshotData); + bytestocopy = min(4096, srcdata.size.QuadPart - bytes_copied.QuadPart); + + hr = StorageBaseImpl_StreamReadAt(src, src_entry, bytes_copied, bytestocopy, + data, &bytesread); + if (SUCCEEDED(hr) && bytesread != bytestocopy) hr = STG_E_READFAULT; + + if (SUCCEEDED(hr)) + hr = StorageBaseImpl_StreamWriteAt(dst, dst_entry, bytes_copied, bytestocopy, + data, &byteswritten); + if (SUCCEEDED(hr) && byteswritten != bytestocopy) hr = STG_E_WRITEFAULT; + + bytes_copied.QuadPart += byteswritten; + } + } + + return hr; +} + +static DirRef TransactedSnapshotImpl_FindFreeEntry(TransactedSnapshotImpl *This) +{ + DirRef result=This->firstFreeEntry; + + while (result < This->entries_size && This->entries[result].inuse) + result++; + + if (result == This->entries_size) + { + ULONG new_size = This->entries_size * 2; + TransactedDirEntry *new_entries; + + new_entries = HeapAlloc(GetProcessHeap(), HEAP_ZERO_MEMORY, sizeof(TransactedDirEntry) * new_size); + if (!new_entries) return DIRENTRY_NULL; + + memcpy(new_entries, This->entries, sizeof(TransactedDirEntry) * This->entries_size); + HeapFree(GetProcessHeap(), 0, This->entries); + + This->entries = new_entries; + This->entries_size = new_size; + } + + This->entries[result].inuse = 1; + + This->firstFreeEntry = result+1; + + return result; +} + +static DirRef TransactedSnapshotImpl_CreateStubEntry( + TransactedSnapshotImpl *This, DirRef parentEntryRef) +{ + DirRef stubEntryRef; + TransactedDirEntry *entry; + + stubEntryRef = TransactedSnapshotImpl_FindFreeEntry(This); + + if (stubEntryRef != DIRENTRY_NULL) + { + entry = &This->entries[stubEntryRef]; + + entry->newTransactedParentEntry = entry->transactedParentEntry = parentEntryRef; + + entry->read = 0; + } + + return stubEntryRef; +} + +static HRESULT TransactedSnapshotImpl_EnsureReadEntry( + TransactedSnapshotImpl *This, DirRef entry) +{ + HRESULT hr=S_OK; + + if (!This->entries[entry].read) + { + hr = StorageBaseImpl_ReadDirEntry(This->transactedParent, + This->entries[entry].transactedParentEntry, + &This->entries[entry].data); + + if (SUCCEEDED(hr) && This->entries[entry].data.leftChild != DIRENTRY_NULL) + { + This->entries[entry].data.leftChild = + TransactedSnapshotImpl_CreateStubEntry(This, This->entries[entry].data.leftChild); + + if (This->entries[entry].data.leftChild == DIRENTRY_NULL) + hr = E_OUTOFMEMORY; + } + + if (SUCCEEDED(hr) && This->entries[entry].data.rightChild != DIRENTRY_NULL) + { + This->entries[entry].data.rightChild = + TransactedSnapshotImpl_CreateStubEntry(This, This->entries[entry].data.rightChild); + + if (This->entries[entry].data.rightChild == DIRENTRY_NULL) + hr = E_OUTOFMEMORY; + } + + if (SUCCEEDED(hr) && This->entries[entry].data.dirRootEntry != DIRENTRY_NULL) + { + This->entries[entry].data.dirRootEntry = + TransactedSnapshotImpl_CreateStubEntry(This, This->entries[entry].data.dirRootEntry); + + if (This->entries[entry].data.dirRootEntry == DIRENTRY_NULL) + hr = E_OUTOFMEMORY; } if (SUCCEEDED(hr)) - hr = IStorage_CopyTo((IStorage*)original, 0, NULL, NULL, - (IStorage*)(*snapshot)); + This->entries[entry].read = 1; + } - if (FAILED(hr)) IStorage_Release((IStorage*)(*snapshot)); + return hr; +} + +static HRESULT TransactedSnapshotImpl_MakeStreamDirty( + TransactedSnapshotImpl *This, DirRef entry) +{ + HRESULT hr = S_OK; + + if (!This->entries[entry].stream_dirty) + { + DirEntry new_entrydata; + + memset(&new_entrydata, 0, sizeof(DirEntry)); + new_entrydata.name[0] = 'S'; + new_entrydata.sizeOfNameString = 1; + new_entrydata.stgType = STGTY_STREAM; + new_entrydata.startingBlock = BLOCK_END_OF_CHAIN; + new_entrydata.leftChild = DIRENTRY_NULL; + new_entrydata.rightChild = DIRENTRY_NULL; + new_entrydata.dirRootEntry = DIRENTRY_NULL; + + hr = StorageBaseImpl_CreateDirEntry(This->scratch, &new_entrydata, + &This->entries[entry].stream_entry); + + if (SUCCEEDED(hr) && This->entries[entry].transactedParentEntry != DIRENTRY_NULL) + { + hr = StorageBaseImpl_CopyStream( + This->scratch, This->entries[entry].stream_entry, + This->transactedParent, This->entries[entry].transactedParentEntry); + + if (FAILED(hr)) + StorageBaseImpl_DestroyDirEntry(This->scratch, This->entries[entry].stream_entry); + } + + if (SUCCEEDED(hr)) + This->entries[entry].stream_dirty = 1; + + if (This->entries[entry].transactedParentEntry != DIRENTRY_NULL) + { + /* Since this entry is modified, and we aren't using its stream data, we + * no longer care about the original entry. */ + DirRef delete_ref; + delete_ref = TransactedSnapshotImpl_CreateStubEntry(This, This->entries[entry].transactedParentEntry); + + if (delete_ref != DIRENTRY_NULL) + This->entries[delete_ref].deleted = 1; + + This->entries[entry].transactedParentEntry = This->entries[entry].newTransactedParentEntry = DIRENTRY_NULL; + } + } + + return hr; +} + +/* Find the first entry in a depth-first traversal. */ +static DirRef TransactedSnapshotImpl_FindFirstChild( + TransactedSnapshotImpl* This, DirRef parent) +{ + DirRef cursor, prev; + TransactedDirEntry *entry; + + cursor = parent; + entry = &This->entries[cursor]; + while (entry->read) + { + if (entry->data.leftChild != DIRENTRY_NULL) + { + prev = cursor; + cursor = entry->data.leftChild; + entry = &This->entries[cursor]; + entry->parent = prev; + } + else if (entry->data.rightChild != DIRENTRY_NULL) + { + prev = cursor; + cursor = entry->data.rightChild; + entry = &This->entries[cursor]; + entry->parent = prev; + } + else if (entry->data.dirRootEntry != DIRENTRY_NULL) + { + prev = cursor; + cursor = entry->data.dirRootEntry; + entry = &This->entries[cursor]; + entry->parent = prev; + } + else + break; + } + + return cursor; +} + +/* Find the next entry in a depth-first traversal. */ +static DirRef TransactedSnapshotImpl_FindNextChild( + TransactedSnapshotImpl* This, DirRef current) +{ + DirRef parent; + TransactedDirEntry *parent_entry; + + parent = This->entries[current].parent; + parent_entry = &This->entries[parent]; + + if (parent != DIRENTRY_NULL && parent_entry->data.dirRootEntry != current) + { + if (parent_entry->data.rightChild != current && parent_entry->data.rightChild != DIRENTRY_NULL) + { + This->entries[parent_entry->data.rightChild].parent = parent; + return TransactedSnapshotImpl_FindFirstChild(This, parent_entry->data.rightChild); + } + + if (parent_entry->data.dirRootEntry != DIRENTRY_NULL) + { + This->entries[parent_entry->data.dirRootEntry].parent = parent; + return TransactedSnapshotImpl_FindFirstChild(This, parent_entry->data.dirRootEntry); + } + } + + return parent; +} + +/* Return TRUE if we've made a copy of this entry for committing to the parent. */ +static inline BOOL TransactedSnapshotImpl_MadeCopy( + TransactedSnapshotImpl* This, DirRef entry) +{ + return entry != DIRENTRY_NULL && + This->entries[entry].newTransactedParentEntry != This->entries[entry].transactedParentEntry; +} + +/* Destroy the entries created by CopyTree. */ +static void TransactedSnapshotImpl_DestroyTemporaryCopy( + TransactedSnapshotImpl* This, DirRef stop) +{ + DirRef cursor; + TransactedDirEntry *entry; + ULARGE_INTEGER zero; + + zero.QuadPart = 0; + + if (!This->entries[This->base.storageDirEntry].read) + return; + + cursor = This->entries[This->base.storageDirEntry].data.dirRootEntry; + + if (cursor == DIRENTRY_NULL) + return; + + cursor = TransactedSnapshotImpl_FindFirstChild(This, cursor); + + while (cursor != DIRENTRY_NULL && cursor != stop) + { + if (TransactedSnapshotImpl_MadeCopy(This, cursor)) + { + entry = &This->entries[cursor]; + + StorageBaseImpl_StreamSetSize(This->transactedParent, + entry->newTransactedParentEntry, zero); + + StorageBaseImpl_DestroyDirEntry(This->transactedParent, + entry->newTransactedParentEntry); + + entry->newTransactedParentEntry = entry->transactedParentEntry; + } + + cursor = TransactedSnapshotImpl_FindNextChild(This, cursor); + } +} + +/* Make a copy of our edited tree that we can use in the parent. */ +static HRESULT TransactedSnapshotImpl_CopyTree(TransactedSnapshotImpl* This) +{ + DirRef cursor; + TransactedDirEntry *entry; + HRESULT hr; + + cursor = This->base.storageDirEntry; + entry = &This->entries[cursor]; + entry->parent = DIRENTRY_NULL; + entry->newTransactedParentEntry = entry->transactedParentEntry; + + if (entry->data.dirRootEntry == DIRENTRY_NULL) + return S_OK; + + This->entries[entry->data.dirRootEntry].parent = DIRENTRY_NULL; + + cursor = TransactedSnapshotImpl_FindFirstChild(This, entry->data.dirRootEntry); + entry = &This->entries[cursor]; + + while (cursor != DIRENTRY_NULL) + { + /* Make a copy of this entry in the transacted parent. */ + if (!entry->read || + (!entry->dirty && !entry->stream_dirty && + !TransactedSnapshotImpl_MadeCopy(This, entry->data.leftChild) && + !TransactedSnapshotImpl_MadeCopy(This, entry->data.rightChild) && + !TransactedSnapshotImpl_MadeCopy(This, entry->data.dirRootEntry))) + entry->newTransactedParentEntry = entry->transactedParentEntry; + else + { + DirEntry newData; + + memcpy(&newData, &entry->data, sizeof(DirEntry)); + + newData.size.QuadPart = 0; + newData.startingBlock = BLOCK_END_OF_CHAIN; + + if (newData.leftChild != DIRENTRY_NULL) + newData.leftChild = This->entries[newData.leftChild].newTransactedParentEntry; + + if (newData.rightChild != DIRENTRY_NULL) + newData.rightChild = This->entries[newData.rightChild].newTransactedParentEntry; + + if (newData.dirRootEntry != DIRENTRY_NULL) + newData.dirRootEntry = This->entries[newData.dirRootEntry].newTransactedParentEntry; + + hr = StorageBaseImpl_CreateDirEntry(This->transactedParent, &newData, + &entry->newTransactedParentEntry); + if (FAILED(hr)) + { + TransactedSnapshotImpl_DestroyTemporaryCopy(This, cursor); + return hr; + } + + hr = StorageBaseImpl_CopyStream( + This->transactedParent, entry->newTransactedParentEntry, + (StorageBaseImpl*)This, cursor); + if (FAILED(hr)) + { + cursor = TransactedSnapshotImpl_FindNextChild(This, cursor); + TransactedSnapshotImpl_DestroyTemporaryCopy(This, cursor); + return hr; + } + } + + cursor = TransactedSnapshotImpl_FindNextChild(This, cursor); + entry = &This->entries[cursor]; } return hr; @@ -4055,10 +4389,13 @@ static HRESULT WINAPI TransactedSnapshotImpl_Commit( DWORD grfCommitFlags) /* [in] */ { TransactedSnapshotImpl* This = (TransactedSnapshotImpl*) iface; + TransactedDirEntry *root_entry; + DirRef i, dir_root_ref; + DirEntry data; + ULARGE_INTEGER zero; HRESULT hr; - DirEntry data, tempStorageData, snapshotRootData; - DirRef tempStorageEntry, oldDirRoot; - StorageInternalImpl *tempStorage; + + zero.QuadPart = 0; TRACE("(%p,%x)\n", iface, grfCommitFlags); @@ -4072,75 +4409,75 @@ static HRESULT WINAPI TransactedSnapshotImpl_Commit( * needed in the rare situation where we have just enough free disk space to * overwrite the existing data. */ - /* Create an orphaned storage in the parent for the new directory structure. */ - memset(&data, 0, sizeof(data)); - data.name[0] = 'D'; - data.sizeOfNameString = 1; - data.stgType = STGTY_STORAGE; - data.leftChild = DIRENTRY_NULL; - data.rightChild = DIRENTRY_NULL; - data.dirRootEntry = DIRENTRY_NULL; - hr = StorageBaseImpl_CreateDirEntry(This->transactedParent, &data, &tempStorageEntry); + root_entry = &This->entries[This->base.storageDirEntry]; + if (!root_entry->read) + return S_OK; + + hr = TransactedSnapshotImpl_CopyTree(This); if (FAILED(hr)) return hr; - tempStorage = StorageInternalImpl_Construct(This->transactedParent, - STGM_READWRITE|STGM_SHARE_EXCLUSIVE, tempStorageEntry); - if (tempStorage) - { - hr = IStorage_CopyTo((IStorage*)This->snapshot, 0, NULL, NULL, - (IStorage*)tempStorage); - - list_init(&tempStorage->ParentListEntry); - - IStorage_Release((IStorage*) tempStorage); - } + if (root_entry->data.dirRootEntry == DIRENTRY_NULL) + dir_root_ref = DIRENTRY_NULL; else - hr = E_OUTOFMEMORY; - - if (FAILED(hr)) - { - DestroyReachableEntries(This->transactedParent, tempStorageEntry); - return hr; - } + dir_root_ref = This->entries[root_entry->data.dirRootEntry].newTransactedParentEntry; /* Update the storage to use the new data in one step. */ hr = StorageBaseImpl_ReadDirEntry(This->transactedParent, - This->transactedParent->storageDirEntry, &data); + root_entry->transactedParentEntry, &data); if (SUCCEEDED(hr)) { - hr = StorageBaseImpl_ReadDirEntry(This->transactedParent, - tempStorageEntry, &tempStorageData); - } - - if (SUCCEEDED(hr)) - { - hr = StorageBaseImpl_ReadDirEntry(This->snapshot, - This->snapshot->storageDirEntry, &snapshotRootData); - } - - if (SUCCEEDED(hr)) - { - oldDirRoot = data.dirRootEntry; - data.dirRootEntry = tempStorageData.dirRootEntry; - data.clsid = snapshotRootData.clsid; - data.ctime = snapshotRootData.ctime; - data.mtime = snapshotRootData.mtime; + data.dirRootEntry = dir_root_ref; + data.clsid = root_entry->data.clsid; + data.ctime = root_entry->data.ctime; + data.mtime = root_entry->data.mtime; hr = StorageBaseImpl_WriteDirEntry(This->transactedParent, - This->transactedParent->storageDirEntry, &data); + root_entry->transactedParentEntry, &data); } if (SUCCEEDED(hr)) { /* Destroy the old now-orphaned data. */ - DestroyReachableEntries(This->transactedParent, oldDirRoot); - StorageBaseImpl_DestroyDirEntry(This->transactedParent, tempStorageEntry); + for (i=0; ientries_size; i++) + { + TransactedDirEntry *entry = &This->entries[i]; + if (entry->inuse) + { + if (entry->deleted) + { + StorageBaseImpl_StreamSetSize(This->transactedParent, + entry->transactedParentEntry, zero); + StorageBaseImpl_DestroyDirEntry(This->transactedParent, + entry->transactedParentEntry); + memset(entry, 0, sizeof(TransactedDirEntry)); + This->firstFreeEntry = min(i, This->firstFreeEntry); + } + else if (entry->read && entry->transactedParentEntry != entry->newTransactedParentEntry) + { + if (entry->transactedParentEntry != DIRENTRY_NULL) + { + StorageBaseImpl_StreamSetSize(This->transactedParent, + entry->transactedParentEntry, zero); + StorageBaseImpl_DestroyDirEntry(This->transactedParent, + entry->transactedParentEntry); + } + if (entry->stream_dirty) + { + StorageBaseImpl_StreamSetSize(This->scratch, entry->stream_entry, zero); + StorageBaseImpl_DestroyDirEntry(This->scratch, entry->stream_entry); + entry->stream_dirty = 0; + } + entry->dirty = 0; + entry->transactedParentEntry = entry->newTransactedParentEntry; + } + } + } } else { - DestroyReachableEntries(This->transactedParent, tempStorageEntry); + TransactedSnapshotImpl_DestroyTemporaryCopy(This, DIRENTRY_NULL); } return hr; @@ -4150,21 +4487,31 @@ static HRESULT WINAPI TransactedSnapshotImpl_Revert( IStorage* iface) { TransactedSnapshotImpl* This = (TransactedSnapshotImpl*) iface; - StorageBaseImpl *newSnapshot; - HRESULT hr; + ULARGE_INTEGER zero; + ULONG i; TRACE("(%p)\n", iface); - /* Create a new copy of the parent data. */ - hr = CreateSnapshotFile(This->transactedParent, &newSnapshot); - if (FAILED(hr)) return hr; - /* Destroy the open objects. */ StorageBaseImpl_DeleteAll(&This->base); - /* Replace our current snapshot. */ - IStorage_Release((IStorage*)This->snapshot); - This->snapshot = newSnapshot; + /* Clear out the scratch file. */ + zero.QuadPart = 0; + for (i=0; ientries_size; i++) + { + if (This->entries[i].stream_dirty) + { + StorageBaseImpl_StreamSetSize(This->scratch, This->entries[i].stream_entry, + zero); + + StorageBaseImpl_DestroyDirEntry(This->scratch, This->entries[i].stream_entry); + } + } + + memset(This->entries, 0, sizeof(TransactedDirEntry) * This->entries_size); + + This->firstFreeEntry = 0; + This->base.storageDirEntry = TransactedSnapshotImpl_CreateStubEntry(This, This->transactedParent->storageDirEntry); return S_OK; } @@ -4185,11 +4532,13 @@ static void TransactedSnapshotImpl_Destroy( StorageBaseImpl *iface) { TransactedSnapshotImpl* This = (TransactedSnapshotImpl*) iface; - TransactedSnapshotImpl_Invalidate(iface); + TransactedSnapshotImpl_Revert((IStorage*)iface); IStorage_Release((IStorage*)This->transactedParent); - IStorage_Release((IStorage*)This->snapshot); + IStorage_Release((IStorage*)This->scratch); + + HeapFree(GetProcessHeap(), 0, This->entries); HeapFree(GetProcessHeap(), 0, This); } @@ -4198,27 +4547,76 @@ static HRESULT TransactedSnapshotImpl_CreateDirEntry(StorageBaseImpl *base, const DirEntry *newData, DirRef *index) { TransactedSnapshotImpl* This = (TransactedSnapshotImpl*) base; + DirRef new_ref; + TransactedDirEntry *new_entry; - return StorageBaseImpl_CreateDirEntry(This->snapshot, - newData, index); + new_ref = TransactedSnapshotImpl_FindFreeEntry(This); + if (new_ref == DIRENTRY_NULL) + return E_OUTOFMEMORY; + + new_entry = &This->entries[new_ref]; + + new_entry->newTransactedParentEntry = new_entry->transactedParentEntry = DIRENTRY_NULL; + new_entry->read = 1; + new_entry->dirty = 1; + memcpy(&new_entry->data, newData, sizeof(DirEntry)); + + *index = new_ref; + + TRACE("%s l=%x r=%x d=%x <-- %x\n", debugstr_w(newData->name), newData->leftChild, newData->rightChild, newData->dirRootEntry, *index); + + return S_OK; } static HRESULT TransactedSnapshotImpl_WriteDirEntry(StorageBaseImpl *base, DirRef index, const DirEntry *data) { TransactedSnapshotImpl* This = (TransactedSnapshotImpl*) base; + HRESULT hr; - return StorageBaseImpl_WriteDirEntry(This->snapshot, - index, data); + TRACE("%x %s l=%x r=%x d=%x\n", index, debugstr_w(data->name), data->leftChild, data->rightChild, data->dirRootEntry); + + hr = TransactedSnapshotImpl_EnsureReadEntry(This, index); + if (FAILED(hr)) return hr; + + memcpy(&This->entries[index].data, data, sizeof(DirEntry)); + + if (index != This->base.storageDirEntry) + { + This->entries[index].dirty = 1; + + if (data->size.QuadPart == 0 && + This->entries[index].transactedParentEntry != DIRENTRY_NULL) + { + /* Since this entry is modified, and we aren't using its stream data, we + * no longer care about the original entry. */ + DirRef delete_ref; + delete_ref = TransactedSnapshotImpl_CreateStubEntry(This, This->entries[index].transactedParentEntry); + + if (delete_ref != DIRENTRY_NULL) + This->entries[delete_ref].deleted = 1; + + This->entries[index].transactedParentEntry = This->entries[index].newTransactedParentEntry = DIRENTRY_NULL; + } + } + + return S_OK; } static HRESULT TransactedSnapshotImpl_ReadDirEntry(StorageBaseImpl *base, DirRef index, DirEntry *data) { TransactedSnapshotImpl* This = (TransactedSnapshotImpl*) base; + HRESULT hr; - return StorageBaseImpl_ReadDirEntry(This->snapshot, - index, data); + hr = TransactedSnapshotImpl_EnsureReadEntry(This, index); + if (FAILED(hr)) return hr; + + memcpy(data, &This->entries[index].data, sizeof(DirEntry)); + + TRACE("%x %s l=%x r=%x d=%x\n", index, debugstr_w(data->name), data->leftChild, data->rightChild, data->dirRootEntry); + + return S_OK; } static HRESULT TransactedSnapshotImpl_DestroyDirEntry(StorageBaseImpl *base, @@ -4226,8 +4624,21 @@ static HRESULT TransactedSnapshotImpl_DestroyDirEntry(StorageBaseImpl *base, { TransactedSnapshotImpl* This = (TransactedSnapshotImpl*) base; - return StorageBaseImpl_DestroyDirEntry(This->snapshot, - index); + if (This->entries[index].transactedParentEntry == DIRENTRY_NULL || + This->entries[index].data.size.QuadPart != 0) + { + /* If we deleted this entry while it has stream data. We must have left the + * data because some other entry is using it, and we need to leave the + * original entry alone. */ + memset(&This->entries[index], 0, sizeof(TransactedDirEntry)); + This->firstFreeEntry = min(index, This->firstFreeEntry); + } + else + { + This->entries[index].deleted = 1; + } + + return S_OK; } static HRESULT TransactedSnapshotImpl_StreamReadAt(StorageBaseImpl *base, @@ -4235,26 +4646,97 @@ static HRESULT TransactedSnapshotImpl_StreamReadAt(StorageBaseImpl *base, { TransactedSnapshotImpl* This = (TransactedSnapshotImpl*) base; - return StorageBaseImpl_StreamReadAt(This->snapshot, - index, offset, size, buffer, bytesRead); + if (This->entries[index].stream_dirty) + { + return StorageBaseImpl_StreamReadAt(This->scratch, + This->entries[index].stream_entry, offset, size, buffer, bytesRead); + } + else if (This->entries[index].transactedParentEntry == DIRENTRY_NULL) + { + /* This stream doesn't live in the parent, and we haven't allocated storage + * for it yet */ + *bytesRead = 0; + return S_OK; + } + else + { + return StorageBaseImpl_StreamReadAt(This->transactedParent, + This->entries[index].transactedParentEntry, offset, size, buffer, bytesRead); + } } static HRESULT TransactedSnapshotImpl_StreamWriteAt(StorageBaseImpl *base, DirRef index, ULARGE_INTEGER offset, ULONG size, const void *buffer, ULONG *bytesWritten) { TransactedSnapshotImpl* This = (TransactedSnapshotImpl*) base; + HRESULT hr; - return StorageBaseImpl_StreamWriteAt(This->snapshot, - index, offset, size, buffer, bytesWritten); + hr = TransactedSnapshotImpl_EnsureReadEntry(This, index); + if (FAILED(hr)) return hr; + + hr = TransactedSnapshotImpl_MakeStreamDirty(This, index); + if (FAILED(hr)) return hr; + + hr = StorageBaseImpl_StreamWriteAt(This->scratch, + This->entries[index].stream_entry, offset, size, buffer, bytesWritten); + + if (SUCCEEDED(hr) && size != 0) + This->entries[index].data.size.QuadPart = max( + This->entries[index].data.size.QuadPart, + offset.QuadPart + size); + + return hr; } static HRESULT TransactedSnapshotImpl_StreamSetSize(StorageBaseImpl *base, DirRef index, ULARGE_INTEGER newsize) { TransactedSnapshotImpl* This = (TransactedSnapshotImpl*) base; + HRESULT hr; - return StorageBaseImpl_StreamSetSize(This->snapshot, - index, newsize); + hr = TransactedSnapshotImpl_EnsureReadEntry(This, index); + if (FAILED(hr)) return hr; + + if (This->entries[index].data.size.QuadPart == newsize.QuadPart) + return S_OK; + + if (newsize.QuadPart == 0) + { + /* Destroy any parent references or entries in the scratch file. */ + if (This->entries[index].stream_dirty) + { + ULARGE_INTEGER zero; + zero.QuadPart = 0; + StorageBaseImpl_StreamSetSize(This->scratch, + This->entries[index].stream_entry, zero); + StorageBaseImpl_DestroyDirEntry(This->scratch, + This->entries[index].stream_entry); + This->entries[index].stream_dirty = 0; + } + else if (This->entries[index].transactedParentEntry != DIRENTRY_NULL) + { + DirRef delete_ref; + delete_ref = TransactedSnapshotImpl_CreateStubEntry(This, This->entries[index].transactedParentEntry); + + if (delete_ref != DIRENTRY_NULL) + This->entries[delete_ref].deleted = 1; + + This->entries[index].transactedParentEntry = This->entries[index].newTransactedParentEntry = DIRENTRY_NULL; + } + } + else + { + hr = TransactedSnapshotImpl_MakeStreamDirty(This, index); + if (FAILED(hr)) return hr; + + hr = StorageBaseImpl_StreamSetSize(This->scratch, + This->entries[index].stream_entry, newsize); + } + + if (SUCCEEDED(hr)) + This->entries[index].data.size = newsize; + + return hr; } static const IStorageVtbl TransactedSnapshotImpl_Vtbl = @@ -4317,17 +4799,35 @@ static HRESULT TransactedSnapshotImpl_Construct(StorageBaseImpl *parentStorage, (*result)->base.filename = parentStorage->filename; - /* Create a new temporary storage to act as the snapshot */ - hr = CreateSnapshotFile(parentStorage, &(*result)->snapshot); + /* Create a new temporary storage to act as the scratch file. */ + hr = StgCreateDocfile(NULL, STGM_READWRITE|STGM_SHARE_EXCLUSIVE|STGM_CREATE, + 0, (IStorage**)&(*result)->scratch); if (SUCCEEDED(hr)) { - (*result)->base.storageDirEntry = (*result)->snapshot->storageDirEntry; + ULONG num_entries = 20; - /* parentStorage already has 1 reference, which we take over here. */ - (*result)->transactedParent = parentStorage; + (*result)->entries = HeapAlloc(GetProcessHeap(), HEAP_ZERO_MEMORY, sizeof(TransactedDirEntry) * num_entries); - parentStorage->transactedChild = (StorageBaseImpl*)*result; + (*result)->entries_size = num_entries; + + (*result)->firstFreeEntry = 0; + + if ((*result)->entries) + { + /* parentStorage already has 1 reference, which we take over here. */ + (*result)->transactedParent = parentStorage; + + parentStorage->transactedChild = (StorageBaseImpl*)*result; + + (*result)->base.storageDirEntry = TransactedSnapshotImpl_CreateStubEntry(*result, parentStorage->storageDirEntry); + } + else + { + IStorage_Release((IStorage*)(*result)->scratch); + + hr = E_OUTOFMEMORY; + } } if (FAILED(hr)) HeapFree(GetProcessHeap(), 0, (*result));