Merge bitcoin/bitcoin#28483: refactor: Return CAutoFile from BlockManager::Open*File()

fa56c42 Return CAutoFile from BlockManager::Open*File() (MarcoFalke)
9999b89 Make BufferedFile to be a CAutoFile wrapper (MarcoFalke)
fa389d9 refactor: Drop unused fclose() from BufferedFile (MarcoFalke)

Pull request description:

  This is required for bitcoin/bitcoin#28052, but makes sense on its own, because offloading logic to `CAutoFile` instead of re-implementing it allows to delete code and complexity.

ACKs for top commit:
  TheCharlatan:
    Re-ACK fa56c42
  willcl-ark:
    tACK fa56c42

Tree-SHA512: fe4638f3a6bd3f9d968cfb9ae3259c9d6cd278fe2912cbc90289851311c8c781099db4c160e775960975c4739098d9af801a8d2d12603f371f8edfe134d8f85a

Author: fanquake

src/bench/load_external.cpp

@@ -5,6 +5,7 @@
 #include <bench/bench.h>
 #include <bench/data.h>
 #include <chainparams.h>
+#include <clientversion.h>
 #include <test/util/setup_common.h>
 #include <util/chaintype.h>
 #include <validation.h>
@@ -54,7 +55,7 @@ static void LoadExternalBlockFile(benchmark::Bench& bench)
     bench.run([&] {
         // "rb" is "binary, O_RDONLY", positioned to the start of the file.
         // The file will be closed by LoadExternalBlockFile().
-        FILE* file{fsbridge::fopen(blkfile, "rb")};
+        CAutoFile file{fsbridge::fopen(blkfile, "rb"), CLIENT_VERSION};
         testing_setup->m_node.chainman->LoadExternalBlockFile(file, &pos, &blocks_with_unknown_parent);
     });
     fs::remove(blkfile);

src/bench/streams_findbyte.cpp

@@ -4,27 +4,31 @@
 
 #include <bench/bench.h>
 
-#include <util/fs.h>
 #include <streams.h>
+#include <util/fs.h>
+
+#include <cstddef>
+#include <cstdint>
+#include <cstdio>
 
 static void FindByte(benchmark::Bench& bench)
 {
     // Setup
-    FILE* file = fsbridge::fopen("streams_tmp", "w+b");
+    CAutoFile file{fsbridge::fopen("streams_tmp", "w+b"), 0};
     const size_t file_size = 200;
     uint8_t data[file_size] = {0};
     data[file_size-1] = 1;
-    fwrite(&data, sizeof(uint8_t), file_size, file);
-    rewind(file);
-    BufferedFile bf{file, /*nBufSize=*/file_size + 1, /*nRewindIn=*/file_size, 0};
+    file << data;
+    std::rewind(file.Get());
+    BufferedFile bf{file, /*nBufSize=*/file_size + 1, /*nRewindIn=*/file_size};
 
     bench.run([&] {
         bf.SetPos(0);
         bf.FindByte(std::byte(1));
     });
 
     // Cleanup
-    bf.fclose();
+    file.fclose();
     fs::remove("streams_tmp");
 }
 

src/index/txindex.cpp

@@ -79,7 +79,7 @@ bool TxIndex::FindTx(const uint256& tx_hash, uint256& block_hash, CTransactionRe
         return false;
     }
 
-    CAutoFile file{m_chainstate->m_blockman.OpenBlockFile(postx, true), CLIENT_VERSION};
+    CAutoFile file{m_chainstate->m_blockman.OpenBlockFile(postx, true)};
     if (file.IsNull()) {
         return error("%s: OpenBlockFile failed", __func__);
     }

src/node/blockstorage.cpp

@@ -459,7 +459,7 @@ bool BlockManager::LoadBlockIndexDB()
     }
     for (std::set<int>::iterator it = setBlkDataFiles.begin(); it != setBlkDataFiles.end(); it++) {
         FlatFilePos pos(*it, 0);
-        if (AutoFile{OpenBlockFile(pos, true)}.IsNull()) {
+        if (OpenBlockFile(pos, true).IsNull()) {
             return false;
         }
     }
@@ -592,7 +592,7 @@ CBlockFileInfo* BlockManager::GetBlockFileInfo(size_t n)
 bool BlockManager::UndoWriteToDisk(const CBlockUndo& blockundo, FlatFilePos& pos, const uint256& hashBlock) const
 {
     // Open history file to append
-    AutoFile fileout{OpenUndoFile(pos)};
+    CAutoFile fileout{OpenUndoFile(pos)};
     if (fileout.IsNull()) {
         return error("%s: OpenUndoFile failed", __func__);
     }
@@ -627,7 +627,7 @@ bool BlockManager::UndoReadFromDisk(CBlockUndo& blockundo, const CBlockIndex& in
     }
 
     // Open history file to read
-    AutoFile filein{OpenUndoFile(pos, true)};
+    CAutoFile filein{OpenUndoFile(pos, true)};
     if (filein.IsNull()) {
         return error("%s: OpenUndoFile failed", __func__);
     }
@@ -715,15 +715,15 @@ FlatFileSeq BlockManager::UndoFileSeq() const
     return FlatFileSeq(m_opts.blocks_dir, "rev", UNDOFILE_CHUNK_SIZE);
 }
 
-FILE* BlockManager::OpenBlockFile(const FlatFilePos& pos, bool fReadOnly) const
+CAutoFile BlockManager::OpenBlockFile(const FlatFilePos& pos, bool fReadOnly) const
 {
-    return BlockFileSeq().Open(pos, fReadOnly);
+    return CAutoFile{BlockFileSeq().Open(pos, fReadOnly), CLIENT_VERSION};
 }
 
 /** Open an undo file (rev?????.dat) */
-FILE* BlockManager::OpenUndoFile(const FlatFilePos& pos, bool fReadOnly) const
+CAutoFile BlockManager::OpenUndoFile(const FlatFilePos& pos, bool fReadOnly) const
 {
-    return UndoFileSeq().Open(pos, fReadOnly);
+    return CAutoFile{UndoFileSeq().Open(pos, fReadOnly), CLIENT_VERSION};
 }
 
 fs::path BlockManager::GetBlockPosFilename(const FlatFilePos& pos) const
@@ -824,7 +824,7 @@ bool BlockManager::FindUndoPos(BlockValidationState& state, int nFile, FlatFileP
 bool BlockManager::WriteBlockToDisk(const CBlock& block, FlatFilePos& pos) const
 {
     // Open history file to append
-    CAutoFile fileout{OpenBlockFile(pos), CLIENT_VERSION};
+    CAutoFile fileout{OpenBlockFile(pos)};
     if (fileout.IsNull()) {
         return error("WriteBlockToDisk: OpenBlockFile failed");
     }
@@ -880,7 +880,7 @@ bool BlockManager::ReadBlockFromDisk(CBlock& block, const FlatFilePos& pos) cons
     block.SetNull();
 
     // Open history file to read
-    CAutoFile filein{OpenBlockFile(pos, true), CLIENT_VERSION};
+    CAutoFile filein{OpenBlockFile(pos, true)};
     if (filein.IsNull()) {
         return error("ReadBlockFromDisk: OpenBlockFile failed for %s", pos.ToString());
     }
@@ -923,7 +923,7 @@ bool BlockManager::ReadRawBlockFromDisk(std::vector<uint8_t>& block, const FlatF
 {
     FlatFilePos hpos = pos;
     hpos.nPos -= 8; // Seek back 8 bytes for meta header
-    AutoFile filein{OpenBlockFile(hpos, true)};
+    CAutoFile filein{OpenBlockFile(hpos, true)};
     if (filein.IsNull()) {
         return error("%s: OpenBlockFile failed for %s", __func__, pos.ToString());
     }
@@ -1015,8 +1015,8 @@ void ImportBlocks(ChainstateManager& chainman, std::vector<fs::path> vImportFile
                 if (!fs::exists(chainman.m_blockman.GetBlockPosFilename(pos))) {
                     break; // No block files left to reindex
                 }
-                FILE* file = chainman.m_blockman.OpenBlockFile(pos, true);
-                if (!file) {
+                CAutoFile file{chainman.m_blockman.OpenBlockFile(pos, true)};
+                if (file.IsNull()) {
                     break; // This error is logged in OpenBlockFile
                 }
                 LogPrintf("Reindexing block file blk%05u.dat...\n", (unsigned int)nFile);
@@ -1036,8 +1036,8 @@ void ImportBlocks(ChainstateManager& chainman, std::vector<fs::path> vImportFile
 
         // -loadblock=
         for (const fs::path& path : vImportFiles) {
-            FILE* file = fsbridge::fopen(path, "rb");
-            if (file) {
+            CAutoFile file{fsbridge::fopen(path, "rb"), CLIENT_VERSION};
+            if (!file.IsNull()) {
                 LogPrintf("Importing blocks file %s...\n", fs::PathToString(path));
                 chainman.LoadExternalBlockFile(file);
                 if (chainman.m_interrupt) {

src/node/blockstorage.h

@@ -29,6 +29,7 @@
 #include <vector>
 
 class BlockValidationState;
+class CAutoFile;
 class CBlock;
 class CBlockFileInfo;
 class CBlockUndo;
@@ -126,7 +127,7 @@ class BlockManager
     FlatFileSeq BlockFileSeq() const;
     FlatFileSeq UndoFileSeq() const;
 
-    FILE* OpenUndoFile(const FlatFilePos& pos, bool fReadOnly = false) const;
+    CAutoFile OpenUndoFile(const FlatFilePos& pos, bool fReadOnly = false) const;
 
     bool WriteBlockToDisk(const CBlock& block, FlatFilePos& pos) const;
     bool UndoWriteToDisk(const CBlockUndo& blockundo, FlatFilePos& pos, const uint256& hashBlock) const;
@@ -278,7 +279,7 @@ class BlockManager
     void UpdatePruneLock(const std::string& name, const PruneLockInfo& lock_info) EXCLUSIVE_LOCKS_REQUIRED(::cs_main);
 
     /** Open a block file (blk?????.dat) */
-    FILE* OpenBlockFile(const FlatFilePos& pos, bool fReadOnly = false) const;
+    CAutoFile OpenBlockFile(const FlatFilePos& pos, bool fReadOnly = false) const;
 
     /** Translation to a filesystem path */
     fs::path GetBlockPosFilename(const FlatFilePos& pos) const;

src/streams.h

@@ -571,7 +571,7 @@ class CAutoFile : public AutoFile
     }
 };
 
-/** Non-refcounted RAII wrapper around a FILE* that implements a ring buffer to
+/** Wrapper around a CAutoFile& that implements a ring buffer to
  *  deserialize from. It guarantees the ability to rewind a given number of bytes.
  *
  *  Will automatically close the file when it goes out of scope if not null.
@@ -580,9 +580,7 @@ class CAutoFile : public AutoFile
 class BufferedFile
 {
 private:
-    const int nVersion;
-
-    FILE *src;            //!< source file
+    CAutoFile& m_src;
     uint64_t nSrcPos{0};  //!< how many bytes have been read from source
     uint64_t m_read_pos{0}; //!< how many bytes have been read from this
     uint64_t nReadLimit;  //!< up to which position we're allowed to read
@@ -598,9 +596,9 @@ class BufferedFile
             readNow = nAvail;
         if (readNow == 0)
             return false;
-        size_t nBytes = fread((void*)&vchBuf[pos], 1, readNow, src);
+        size_t nBytes{m_src.detail_fread(Span{vchBuf}.subspan(pos, readNow))};
         if (nBytes == 0) {
-            throw std::ios_base::failure(feof(src) ? "BufferedFile::Fill: end of file" : "BufferedFile::Fill: fread failed");
+            throw std::ios_base::failure{m_src.feof() ? "BufferedFile::Fill: end of file" : "BufferedFile::Fill: fread failed"};
         }
         nSrcPos += nBytes;
         return true;
@@ -629,36 +627,18 @@ class BufferedFile
     }
 
 public:
-    BufferedFile(FILE* fileIn, uint64_t nBufSize, uint64_t nRewindIn, int nVersionIn)
-        : nVersion{nVersionIn}, nReadLimit{std::numeric_limits<uint64_t>::max()}, nRewind{nRewindIn}, vchBuf(nBufSize, std::byte{0})
+    BufferedFile(CAutoFile& file, uint64_t nBufSize, uint64_t nRewindIn)
+        : m_src{file}, nReadLimit{std::numeric_limits<uint64_t>::max()}, nRewind{nRewindIn}, vchBuf(nBufSize, std::byte{0})
     {
         if (nRewindIn >= nBufSize)
             throw std::ios_base::failure("Rewind limit must be less than buffer size");
-        src = fileIn;
-    }
-
-    ~BufferedFile()
-    {
-        fclose();
     }
 
-    // Disallow copies
-    BufferedFile(const BufferedFile&) = delete;
-    BufferedFile& operator=(const BufferedFile&) = delete;
-
-    int GetVersion() const { return nVersion; }
-
-    void fclose()
-    {
-        if (src) {
-            ::fclose(src);
-            src = nullptr;
-        }
-    }
+    int GetVersion() const { return m_src.GetVersion(); }
 
     //! check whether we're at the end of the source file
     bool eof() const {
-        return m_read_pos == nSrcPos && feof(src);
+        return m_read_pos == nSrcPos && m_src.feof();
     }
 
     //! read a number of bytes

src/test/blockmanager_tests.cpp

@@ -74,13 +74,13 @@ BOOST_FIXTURE_TEST_CASE(blockmanager_scan_unlink_already_pruned_files, TestChain
     // Check that the file is not unlinked after ScanAndUnlinkAlreadyPrunedFiles
     // if m_have_pruned is not yet set
     WITH_LOCK(chainman->GetMutex(), blockman.ScanAndUnlinkAlreadyPrunedFiles());
-    BOOST_CHECK(!AutoFile(blockman.OpenBlockFile(pos, true)).IsNull());
+    BOOST_CHECK(!blockman.OpenBlockFile(pos, true).IsNull());
 
     // Check that the file is unlinked after ScanAndUnlinkAlreadyPrunedFiles
     // once m_have_pruned is set
     blockman.m_have_pruned = true;
     WITH_LOCK(chainman->GetMutex(), blockman.ScanAndUnlinkAlreadyPrunedFiles());
-    BOOST_CHECK(AutoFile(blockman.OpenBlockFile(pos, true)).IsNull());
+    BOOST_CHECK(blockman.OpenBlockFile(pos, true).IsNull());
 
     // Check that calling with already pruned files doesn't cause an error
     WITH_LOCK(chainman->GetMutex(), blockman.ScanAndUnlinkAlreadyPrunedFiles());
@@ -90,7 +90,7 @@ BOOST_FIXTURE_TEST_CASE(blockmanager_scan_unlink_already_pruned_files, TestChain
     BOOST_CHECK_NE(old_tip, new_tip);
     const int new_file_number{WITH_LOCK(chainman->GetMutex(), return new_tip->GetBlockPos().nFile)};
     const FlatFilePos new_pos(new_file_number, 0);
-    BOOST_CHECK(!AutoFile(blockman.OpenBlockFile(new_pos, true)).IsNull());
+    BOOST_CHECK(!blockman.OpenBlockFile(new_pos, true).IsNull());
 }
 
 BOOST_FIXTURE_TEST_CASE(blockmanager_block_data_availability, TestChain100Setup)

src/test/fuzz/buffered_file.cpp

@@ -19,15 +19,12 @@ FUZZ_TARGET(buffered_file)
     FuzzedDataProvider fuzzed_data_provider{buffer.data(), buffer.size()};
     FuzzedFileProvider fuzzed_file_provider = ConsumeFile(fuzzed_data_provider);
     std::optional<BufferedFile> opt_buffered_file;
-    FILE* fuzzed_file = fuzzed_file_provider.open();
+    CAutoFile fuzzed_file{fuzzed_file_provider.open(), 0};
     try {
-        opt_buffered_file.emplace(fuzzed_file, fuzzed_data_provider.ConsumeIntegralInRange<uint64_t>(0, 4096), fuzzed_data_provider.ConsumeIntegralInRange<uint64_t>(0, 4096), fuzzed_data_provider.ConsumeIntegral<int>());
+        opt_buffered_file.emplace(fuzzed_file, fuzzed_data_provider.ConsumeIntegralInRange<uint64_t>(0, 4096), fuzzed_data_provider.ConsumeIntegralInRange<uint64_t>(0, 4096));
     } catch (const std::ios_base::failure&) {
-        if (fuzzed_file != nullptr) {
-            fclose(fuzzed_file);
-        }
     }
-    if (opt_buffered_file && fuzzed_file != nullptr) {
+    if (opt_buffered_file && !fuzzed_file.IsNull()) {
         bool setpos_fail = false;
         LIMITED_WHILE(fuzzed_data_provider.ConsumeBool(), 10000) {
             CallOneOf(

src/test/fuzz/load_external_block_file.cpp

@@ -3,6 +3,7 @@
 // file COPYING or http://www.opensource.org/licenses/mit-license.php.
 
 #include <chainparams.h>
+#include <clientversion.h>
 #include <flatfile.h>
 #include <test/fuzz/FuzzedDataProvider.h>
 #include <test/fuzz/fuzz.h>
@@ -27,8 +28,8 @@ FUZZ_TARGET(load_external_block_file, .init = initialize_load_external_block_fil
 {
     FuzzedDataProvider fuzzed_data_provider{buffer.data(), buffer.size()};
     FuzzedFileProvider fuzzed_file_provider = ConsumeFile(fuzzed_data_provider);
-    FILE* fuzzed_block_file = fuzzed_file_provider.open();
-    if (fuzzed_block_file == nullptr) {
+    CAutoFile fuzzed_block_file{fuzzed_file_provider.open(), CLIENT_VERSION};
+    if (fuzzed_block_file.IsNull()) {
         return;
     }
     if (fuzzed_data_provider.ConsumeBool()) {