Adding upstream version 0.25.upstream/0.25upstream

Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>

1 files changed, 189 insertions, 0 deletions

diff --git a/delete.cc b/delete.cc
new file mode 100644
index 0000000..6e54cf3
--- /dev/null
+++ b/delete.cc
@@ -0,0 +1,189 @@
+/* Tarlz - Archiver with multimember lzip compression
+   Copyright (C) 2013-2024 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/>.
+*/
+
+#define _FILE_OFFSET_BITS 64
+
+#include <cctype>
+#include <cerrno>
+#include <cstdio>
+#include <stdint.h>	// for lzlib.h
+#include <unistd.h>
+#include <lzlib.h>
+
+#include "tarlz.h"
+#include "arg_parser.h"
+#include "lzip_index.h"
+#include "archive_reader.h"
+
+
+bool safe_seek( const int fd, const long long pos )
+  {
+  if( lseek( fd, pos, SEEK_SET ) == pos ) return true;
+  show_error( seek_msg, errno ); return false;
+  }
+
+
+int tail_copy( const Arg_parser & parser, const Archive_descriptor & ad,
+               std::vector< char > & name_pending, const long long istream_pos,
+               const int outfd, int retval )
+  {
+  const long long rest = ad.lzip_index.file_size() - istream_pos;
+  if( istream_pos > 0 && rest > 0 &&
+      ( !safe_seek( ad.infd, istream_pos ) ||
+        !copy_file( ad.infd, outfd, rest ) ) )
+    { show_file_error( ad.namep, "Error during tail copy." );
+      return retval ? retval : 1; }
+  const long long ostream_pos = lseek( outfd, 0, SEEK_CUR );
+  if( ostream_pos < 0 )
+    { show_file_error( ad.namep, seek_msg, errno ); retval = 1; }
+  else if( ostream_pos > 0 && ostream_pos < ad.lzip_index.file_size() )
+    {
+    int ret;
+    do ret = ftruncate( outfd, ostream_pos );
+      while( ret != 0 && errno == EINTR );
+    if( ret != 0 || lseek( outfd, 0, SEEK_END ) != ostream_pos )
+      {
+      show_file_error( ad.namep, "Can't truncate archive", errno );
+      if( retval < 1 ) retval = 1;
+      }
+    }
+
+  if( ( close( outfd ) | close( ad.infd ) ) != 0 && retval == 0 )
+    { show_file_error( ad.namep, eclosa_msg, errno ); retval = 1; }
+
+  if( retval == 0 )
+    for( int i = 0; i < parser.arguments(); ++i )
+      if( nonempty_arg( parser, i ) && name_pending[i] )
+        { show_file_error( parser.argument( i ).c_str(), nfound_msg );
+          retval = 1; }
+  return retval;
+  }
+
+
+/* Deleting from a corrupt archive must not worsen the corruption. Stop and
+   tail-copy as soon as corruption is found.
+*/
+int delete_members( const Cl_options & cl_opts )
+  {
+  if( cl_opts.num_files <= 0 )
+    { if( verbosity >= 1 ) show_error( "Nothing to delete." ); return 0; }
+  if( cl_opts.archive_name.empty() )
+    { show_error( "Deleting from stdin not implemented yet." ); return 1; }
+  const Archive_descriptor ad( cl_opts.archive_name );
+  if( ad.infd < 0 ) return 1;
+  const int outfd = open_outstream( cl_opts.archive_name, false );
+  if( outfd < 0 ) { close( ad.infd ); return 1; }
+
+  // mark member names to be deleted
+  std::vector< char > name_pending( cl_opts.parser.arguments(), false );
+  for( int i = 0; i < cl_opts.parser.arguments(); ++i )
+    if( nonempty_arg( cl_opts.parser, i ) &&
+        !Exclude::excluded( cl_opts.parser.argument( i ).c_str() ) )
+      name_pending[i] = true;
+
+  if( ad.indexed )		// archive is a compressed regular file
+    return delete_members_lz( cl_opts, ad, name_pending, outfd );
+  if( !ad.seekable )
+    { show_file_error( ad.namep, "Archive is not seekable." ); return 1; }
+  if( ad.lzip_index.file_size() < 3 * header_size )
+    { show_file_error( ad.namep, has_lz_ext( ad.name ) ?
+                       posix_lz_msg : posix_msg ); return 2; }
+  // archive is uncompressed seekable, unless compressed corrupt
+
+  Archive_reader ar( ad );		// serial reader
+  Resizable_buffer rbuf;
+  long long istream_pos = 0;		// source of next data move
+  long long member_begin = 0;		// first pos of current tar member
+  Extended extended;			// metadata from extended records
+  int retval = 0;
+  bool prev_extended = false;		// prev header was extended
+  if( !rbuf.size() ) { show_error( mem_msg ); return 1; }
+
+  while( true )				// process one tar header per iteration
+    {
+    if( !prev_extended && ( member_begin = lseek( ad.infd, 0, SEEK_CUR ) ) < 0 )
+      { show_file_error( ad.namep, seek_msg, errno ); retval = 1; break; }
+    Tar_header header;
+    if( ( retval = ar.read( header, header_size ) ) != 0 )
+      { show_file_error( ad.namep, ar.e_msg(), ar.e_code() ); break; }
+    if( !check_ustar_chksum( header ) )		// error or EOA
+      {
+      if( block_is_zero( header, header_size ) )	// EOA
+        {
+        if( prev_extended && !cl_opts.permissive )
+          { show_file_error( ad.namep, fv_msg1 ); retval = 2; }
+        break;
+        }
+      // posix format already checked by archive reader
+      show_file_error( ad.namep, bad_hdr_msg );
+      retval = 2; break;
+      }
+
+    const Typeflag typeflag = (Typeflag)header[typeflag_o];
+    if( typeflag == tf_global )
+      {
+      if( prev_extended && !cl_opts.permissive )
+        { show_file_error( ad.namep, fv_msg2 ); retval = 2; break; }
+      Extended dummy;		// global headers are parsed and ignored
+      retval = ar.parse_records( dummy, header, rbuf, gblrec_msg, true );
+      if( retval )
+        { show_file_error( ad.namep, ar.e_msg(), ar.e_code() ); break; }
+      continue;
+      }
+    if( typeflag == tf_extended )
+      {
+      if( prev_extended && !cl_opts.permissive )
+        { show_file_error( ad.namep, fv_msg3 ); retval = 2; break; }
+      if( ( retval = ar.parse_records( extended, header, rbuf, extrec_msg,
+                                       cl_opts.permissive ) ) != 0 )
+        { show_file_error( ad.namep, ar.e_msg(), ar.e_code() ); break; }
+      if( !extended.crc_present() && cl_opts.missing_crc )
+        { show_file_error( ad.namep, miscrc_msg ); retval = 2; break; }
+      prev_extended = true; continue;
+      }
+    prev_extended = false;
+
+    extended.fill_from_ustar( header );		// copy metadata from header
+
+    if( ( retval = ar.skip_member( extended ) ) != 0 )
+      { show_file_error( ad.namep, seek_msg, errno ); break; }
+
+    // delete tar member
+    if( !check_skip_filename( cl_opts, name_pending, extended.path().c_str() ) )
+      {
+      print_removed_prefix( extended.removed_prefix );
+      if( !show_member_name( extended, header, 1, rbuf ) )
+        { retval = 1; break; }
+      const long long pos = lseek( ad.infd, 0, SEEK_CUR );
+      if( pos <= 0 || pos <= member_begin || member_begin < istream_pos )
+        { show_file_error( ad.namep, seek_msg, errno ); retval = 1; break; }
+      const long long size = member_begin - istream_pos;
+      if( size > 0 )	// move pending data each time a member is deleted
+        {
+        if( istream_pos == 0 )
+          { if( !safe_seek( outfd, size ) ) { retval = 1; break; } }
+        else if( !safe_seek( ad.infd, istream_pos ) ||
+                 !copy_file( ad.infd, outfd, size ) ||
+                 !safe_seek( ad.infd, pos ) ) { retval = 1; break; }
+        }
+      istream_pos = pos;
+      }
+    extended.reset();
+    }
+
+  return tail_copy( cl_opts.parser, ad, name_pending, istream_pos, outfd, retval );
+  }