Add utility function to copy blocks

test/utils/BlockStoreUtilsTest.cpp

@@ -32,14 +32,16 @@ public:
   unique_ptr<BlockStore> blockStore;
 };
 
-TEST_F(BlockStoreUtilsTest, CopyEmptyBlock) {
+class BlockStoreUtilsTest_CopyToNewBlock: public BlockStoreUtilsTest {};
+
+TEST_F(BlockStoreUtilsTest_CopyToNewBlock, CopyEmptyBlock) {
   auto block = blockStore->create(0);
   auto block2 = copyToNewBlock(blockStore.get(), *block);
 
   EXPECT_EQ(0u, block2->size());
 }
 
-TEST_F(BlockStoreUtilsTest, CopyZeroBlock) {
+TEST_F(BlockStoreUtilsTest_CopyToNewBlock, CopyZeroBlock) {
   auto block = blockStore->create(SIZE);
   auto block2 = copyToNewBlock(blockStore.get(), *block);
 
@@ -47,7 +49,7 @@ TEST_F(BlockStoreUtilsTest, CopyZeroBlock) {
   EXPECT_EQ(0, std::memcmp(ZEROES.data(), block2->data(), SIZE));
 }
 
-TEST_F(BlockStoreUtilsTest, CopyDataBlock) {
+TEST_F(BlockStoreUtilsTest_CopyToNewBlock, CopyDataBlock) {
   auto block = blockStore->create(SIZE);
   std::memcpy(block->data(), dataFixture.data(), SIZE);
   auto block2 = copyToNewBlock(blockStore.get(), *block);
@@ -56,7 +58,7 @@ TEST_F(BlockStoreUtilsTest, CopyDataBlock) {
   EXPECT_EQ(0, std::memcmp(dataFixture.data(), block2->data(), SIZE));
 }
 
-TEST_F(BlockStoreUtilsTest, OriginalBlockUnchanged) {
+TEST_F(BlockStoreUtilsTest_CopyToNewBlock, OriginalBlockUnchanged) {
   auto block = blockStore->create(SIZE);
   std::memcpy(block->data(), dataFixture.data(), SIZE);
   auto block2 = copyToNewBlock(blockStore.get(), *block);
@@ -64,3 +66,38 @@ TEST_F(BlockStoreUtilsTest, OriginalBlockUnchanged) {
   EXPECT_EQ(SIZE, block->size());
   EXPECT_EQ(0, std::memcmp(dataFixture.data(), block->data(), SIZE));
 }
+
+class BlockStoreUtilsTest_CopyToExistingBlock: public BlockStoreUtilsTest {};
+
+TEST_F(BlockStoreUtilsTest_CopyToExistingBlock, CopyEmptyBlock) {
+  auto block = blockStore->create(0);
+  auto block2 = blockStore->create(0);
+  copyTo(block2.get(), *block);
+}
+
+TEST_F(BlockStoreUtilsTest_CopyToExistingBlock, CopyZeroBlock) {
+  auto block = blockStore->create(SIZE);
+  auto block2 = blockStore->create(SIZE);
+  std::memcpy(block2->data(), dataFixture.data(), SIZE);
+  copyTo(block2.get(), *block);
+
+  EXPECT_EQ(0, std::memcmp(ZEROES.data(), block2->data(), SIZE));
+}
+
+TEST_F(BlockStoreUtilsTest_CopyToExistingBlock, CopyDataBlock) {
+  auto block = blockStore->create(SIZE);
+  std::memcpy(block->data(), dataFixture.data(), SIZE);
+  auto block2 = blockStore->create(SIZE);
+  copyTo(block2.get(), *block);
+
+  EXPECT_EQ(0, std::memcmp(dataFixture.data(), block2->data(), SIZE));
+}
+
+TEST_F(BlockStoreUtilsTest_CopyToExistingBlock, OriginalBlockUnchanged) {
+  auto block = blockStore->create(SIZE);
+  std::memcpy(block->data(), dataFixture.data(), SIZE);
+  auto block2 = blockStore->create(SIZE);
+  copyTo(block2.get(), *block);
+
+  EXPECT_EQ(0, std::memcmp(dataFixture.data(), block->data(), SIZE));
+}

utils/BlockStoreUtils.cpp

@@ -1,6 +1,7 @@
 #include <messmer/blockstore/interface/BlockStore.h>
 #include <messmer/blockstore/utils/BlockStoreUtils.h>
 #include <memory>
+#include <cassert>
 
 using std::unique_ptr;
 
@@ -9,9 +10,14 @@ namespace utils {
 
 unique_ptr<Block> copyToNewBlock(BlockStore *blockStore, const Block &block) {
   auto newBlock = blockStore->create(block.size());
-  std::memcpy(newBlock->data(), block.data(), block.size());
+  copyTo(newBlock.get(), block);
   return newBlock;
 }
 
+void copyTo(Block *target, const Block &source) {
+  assert(target->size() == source.size());
+  std::memcpy(target->data(), source.data(), source.size());
+}
+
 }
 }

utils/BlockStoreUtils.h

@@ -10,6 +10,7 @@ class Block;
 namespace utils {
 
 std::unique_ptr<Block> copyToNewBlock(BlockStore *blockStore, const Block &block);
+void copyTo(Block *target, const Block &source);
 
 }
 }