1 files changed, 91 insertions, 0 deletions
diff --git a/lzip_index.h b/lzip_index.h
new file mode 100644
index 0000000..442512d
--- /dev/null
+++ b/lzip_index.h
@@ -0,0 +1,91 @@
+/* Lzip - LZMA lossless data compressor
+   Copyright (C) 2008-2022 Antonio Diaz Diaz.
+
+   This program is free software: you can redistribute it and/or modify
+   it under the terms of the GNU General Public License as published by
+   the Free Software Foundation, either version 2 of the License, or
+   (at your option) any later version.
+
+   This program is distributed in the hope that it will be useful,
+   but WITHOUT ANY WARRANTY; without even the implied warranty of
+   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+   GNU General Public License for more details.
+
+   You should have received a copy of the GNU General Public License
+   along with this program.  If not, see <http://www.gnu.org/licenses/>.
+*/
+
+#ifndef INT64_MAX
+#define INT64_MAX  0x7FFFFFFFFFFFFFFFLL
+#endif
+
+
+class Block
+  {
+  long long pos_, size_;		// pos + size <= INT64_MAX
+
+public:
+  Block( const long long p, const long long s ) : pos_( p ), size_( s ) {}
+
+  long long pos() const { return pos_; }
+  long long size() const { return size_; }
+  long long end() const { return pos_ + size_; }
+
+  void pos( const long long p ) { pos_ = p; }
+  void size( const long long s ) { size_ = s; }
+  };
+
+
+class Lzip_index
+  {
+  struct Member
+    {
+    Block dblock, mblock;		// data block, member block
+    unsigned dictionary_size;
+
+    Member( const long long dp, const long long ds,
+            const long long mp, const long long ms, const unsigned dict_size )
+      : dblock( dp, ds ), mblock( mp, ms ), dictionary_size( dict_size ) {}
+    };
+
+  std::vector< Member > member_vector;
+  std::string error_;
+  const long long insize;
+  int retval_;
+  unsigned dictionary_size_;	// largest dictionary size in the file
+
+  bool check_header_error( const Lzip_header & header );
+  void set_errno_error( const char * const msg );
+  void set_num_error( const char * const msg, unsigned long long num );
+  bool read_header( const int fd, Lzip_header & header, const long long pos );
+  bool skip_trailing_data( const int fd, unsigned long long & pos,
+         const bool ignore_trailing, const bool loose_trailing );
+
+public:
+  Lzip_index( const int infd, const bool ignore_trailing,
+              const bool loose_trailing );
+
+  long members() const { return member_vector.size(); }
+  const std::string & error() const { return error_; }
+  int retval() const { return retval_; }
+  unsigned dictionary_size() const { return dictionary_size_; }
+
+  long long udata_size() const
+    { if( member_vector.empty() ) return 0;
+      return member_vector.back().dblock.end(); }
+
+  long long cdata_size() const
+    { if( member_vector.empty() ) return 0;
+      return member_vector.back().mblock.end(); }
+
+  // total size including trailing data (if any)
+  long long file_size() const
+    { if( insize >= 0 ) return insize; else return 0; }
+
+  const Block & dblock( const long i ) const
+    { return member_vector[i].dblock; }
+  const Block & mblock( const long i ) const
+    { return member_vector[i].mblock; }
+  unsigned dictionary_size( const long i ) const
+    { return member_vector[i].dictionary_size; }
+  };