flatfile.cpp raw

   1  // Copyright (c) 2009-2010 Satoshi Nakamoto
   2  // Copyright (c) 2009-2022 The Limenka developers
   3  // Distributed under the MIT software license, see the accompanying
   4  // file COPYING or http://www.opensource.org/licenses/mit-license.php.
   5  
   6  #include <stdexcept>
   7  
   8  #include <flatfile.h>
   9  #include <logging.h>
  10  #include <tinyformat.h>
  11  #include <util/fs_helpers.h>
  12  
  13  FlatFileSeq::FlatFileSeq(fs::path dir, const char* prefix, size_t chunk_size) :
  14      m_dir(std::move(dir)),
  15      m_prefix(prefix),
  16      m_chunk_size(chunk_size)
  17  {
  18      if (chunk_size == 0) {
  19          throw std::invalid_argument("chunk_size must be positive");
  20      }
  21  }
  22  
  23  std::string FlatFilePos::ToString() const
  24  {
  25      return strprintf("FlatFilePos(nFile=%i, nPos=%i)", nFile, nPos);
  26  }
  27  
  28  fs::path FlatFileSeq::FileName(const FlatFilePos& pos) const
  29  {
  30      return m_dir / fs::u8path(strprintf("%s%05u.dat", m_prefix, pos.nFile));
  31  }
  32  
  33  FILE* FlatFileSeq::Open(const FlatFilePos& pos, bool read_only) const
  34  {
  35      if (pos.IsNull()) {
  36          return nullptr;
  37      }
  38      fs::path path = FileName(pos);
  39      fs::create_directories(path.parent_path());
  40      FILE* file = fsbridge::fopen(path, read_only ? "rb": "rb+");
  41      if (!file && !read_only)
  42          file = fsbridge::fopen(path, "wb+");
  43      if (!file) {
  44          LogError("Unable to open file %s", fs::PathToString(path));
  45          return nullptr;
  46      }
  47      if (pos.nPos && fseek(file, pos.nPos, SEEK_SET)) {
  48          LogError("Unable to seek to position %u of %s", pos.nPos, fs::PathToString(path));
  49          if (fclose(file) != 0) {
  50              LogError("Unable to close file %s", fs::PathToString(path));
  51          }
  52          return nullptr;
  53      }
  54      return file;
  55  }
  56  
  57  size_t FlatFileSeq::Allocate(const FlatFilePos& pos, size_t add_size, bool& out_of_space) const
  58  {
  59      out_of_space = false;
  60  
  61      unsigned int n_old_chunks = (pos.nPos + m_chunk_size - 1) / m_chunk_size;
  62      unsigned int n_new_chunks = (pos.nPos + add_size + m_chunk_size - 1) / m_chunk_size;
  63      if (n_new_chunks > n_old_chunks) {
  64          size_t old_size = pos.nPos;
  65          size_t new_size = n_new_chunks * m_chunk_size;
  66          size_t inc_size = new_size - old_size;
  67  
  68          if (CheckDiskSpace(m_dir, inc_size)) {
  69              FILE *file = Open(pos);
  70              if (file) {
  71                  LogDebug(BCLog::VALIDATION, "Pre-allocating up to position 0x%x in %s%05u.dat\n", new_size, m_prefix, pos.nFile);
  72                  AllocateFileRange(file, pos.nPos, inc_size);
  73                  if (fclose(file) != 0) {
  74                      LogError("Cannot close file %s%05u.dat after extending it with %u bytes", m_prefix, pos.nFile, new_size);
  75                      return 0;
  76                  }
  77                  return inc_size;
  78              }
  79          } else {
  80              out_of_space = true;
  81          }
  82      }
  83      return 0;
  84  }
  85  
  86  bool FlatFileSeq::Flush(const FlatFilePos& pos, bool finalize) const
  87  {
  88      FILE* file = Open(FlatFilePos(pos.nFile, 0)); // Avoid fseek to nPos
  89      if (!file) {
  90          LogError("%s: failed to open file %d\n", __func__, pos.nFile);
  91          return false;
  92      }
  93      if (finalize && !TruncateFile(file, pos.nPos)) {
  94          LogError("%s: failed to truncate file %d\n", __func__, pos.nFile);
  95          if (fclose(file) != 0) {
  96              LogError("Failed to close file %d", pos.nFile);
  97          }
  98          return false;
  99      }
 100      if (!FileCommit(file)) {
 101          LogError("%s: failed to commit file %d\n", __func__, pos.nFile);
 102          if (fclose(file) != 0) {
 103              LogError("Failed to close file %d", pos.nFile);
 104          }
 105          return false;
 106      }
 107      DirectoryCommit(m_dir);
 108  
 109      if (fclose(file) != 0) {
 110          LogError("Failed to close file %d after flush", pos.nFile);
 111          return false;
 112      }
 113      return true;
 114  }
 115