Adding upstream version 0.8.upstream/0.8

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

1 files changed, 243 insertions, 155 deletions

diff --git a/extract.cc b/extract.cc
index 67f4a20..58cda61 100644
--- a/extract.cc
+++ b/extract.cc
@@ -28,6 +28,10 @@
 #include <unistd.h>
 #include <utime.h>
 #include <sys/stat.h>
+#include <sys/types.h>
+#if defined(__GNU_LIBRARY__)
+#include <sys/sysmacros.h>		// for makedev
+#endif
 #include <lzlib.h>
 
 #include "arg_parser.h"
@@ -38,6 +42,17 @@
 namespace {
 
 int gretval = 0;
+bool has_lz_ext;			// global var for archive_read
+
+void skip_warn( const bool reset = false )	// avoid duplicate warnings
+  {
+  static bool skipping = false;
+
+  if( reset ) skipping = false;
+  else if( !skipping )
+    { skipping = true; show_error( "Skipping to next header." ); }
+  }
+
 
 bool make_path( const std::string & name )
   {
@@ -68,42 +83,6 @@ bool make_path( const std::string & name )
   }
 
 
-// Returns in buf the first rd bytes of the second lzip member or
-// the first 512 bytes of the second tar member, and sets islz if lzip member
-bool skip_first_member( const int infd, uint8_t * const buf,
-                        int & rd, bool & islz )
-  {
-  while( true )
-    {
-    for( int i = 0; i < rd; ++i )
-      if( buf[i] == 'L' && (*(Lzip_header *)( buf + i )).verify_prefix( rd - i ) )
-        {
-        const int ts = rd - i;				// tail size
-        std::memmove( buf, buf + i, ts );
-        if( ts >= (int)sizeof lzip_magic )
-          { rd = ts; islz = true; return true; }
-        int rd2 = readblock( infd, buf + ts, header_size - ts );
-        if( rd2 != header_size - ts && errno )
-          { show_error( "Error reading archive", errno ); return false; }
-        if( ts + rd2 >= min_member_size &&
-            (*(Lzip_header *)buf).verify_magic() )
-          { rd = ts + rd2; islz = true; return true; }
-        std::memmove( buf, buf + ts, rd2 );
-        int rd3 = readblock( infd, buf + rd2, header_size - rd2 );
-        if( rd3 != header_size - rd2 && errno )
-          { show_error( "Error reading archive", errno ); return false; }
-        rd = rd2 + rd3; i = -1;
-        }
-    if( rd < header_size ) return false;		// eof
-    if( rd == header_size && verify_ustar_chksum( buf ) )
-      { islz = false; return true; }
-    rd = readblock( infd, buf, header_size );
-    if( rd != header_size && errno )
-      { show_error( "Error reading archive", errno ); return false; }
-    }
-  }
-
-
 inline bool block_is_zero( const uint8_t * const buf, const int size )
   {
   for( int i = 0; i < size; ++i ) if( buf[i] != 0 ) return false;
@@ -111,58 +90,83 @@ inline bool block_is_zero( const uint8_t * const buf, const int size )
   }
 
 
-bool archive_read( const int infd, uint8_t * const buf, const int size )
+// Return value: 0 = OK, 1 = damaged member, 2 = fatal error.
+// If sizep and error, return in *sizep the number of bytes read.
+// The first 6 bytes of the archive must be intact for islz to be meaningful.
+int archive_read( const int infd, uint8_t * const buf, const int size,
+                  int * const sizep = 0 )
   {
   static LZ_Decoder * decoder = 0;
-  static bool first_call = true;
   static bool at_eof = false;
+  static bool fatal = false;
+  static bool first_call = true;
 
+  if( sizep ) *sizep = 0;
+  if( fatal ) return 2;
   if( first_call )					// check format
     {
     first_call = false;
     if( size != header_size )
       internal_error( "size != header_size on first call." );
-    int rd = readblock( infd, buf, size );
+    const int rd = readblock( infd, buf, size );
+    if( sizep ) *sizep = rd;
     if( rd != size && errno )
-      { show_error( "Error reading archive", errno ); return false; }
-    bool islz =
-      ( rd >= min_member_size && (*(Lzip_header *)buf).verify_magic() );
+      { show_error( "Error reading archive", errno ); fatal = true; return 2; }
+    const Lzip_header & header = (*(const Lzip_header *)buf);
+    bool islz = ( rd >= min_member_size && header.verify_magic() &&
+                  isvalid_ds( header.dictionary_size() ) );
     const bool istar = ( rd == size && verify_ustar_chksum( buf ) );
     const bool iseof =
       ( !islz && !istar && rd == size && block_is_zero( buf, size ) );
-    if( !islz && !istar && !iseof )
+    if( !islz && !istar && !iseof )		// corrupt or invalid format
       {
-      show_error( "This does not look like a tar archive." );
-      show_error( "Skipping to next header." );
-//      std::fprintf( stderr, "%07o\n", ustar_chksum( buf ) );
-      gretval = 2;
-      if( !skip_first_member( infd, buf, rd, islz ) ) return false;
+      show_error( "This does not look like a POSIX tar archive." );
+      if( has_lz_ext ) islz = true;
+      if( verbosity >= 2 && !islz && rd == size )
+        std::fprintf( stderr, "ustar chksum = %07o\n", ustar_chksum( buf ) );
+      if( !islz ) return 1;
       }
-    if( !islz ) return true;				// uncompressed
+    if( !islz )						// uncompressed
+      { if( rd == size ) return 0; fatal = true; return 2; }
     decoder = LZ_decompress_open();			// compressed
     if( !decoder || LZ_decompress_errno( decoder ) != LZ_ok )
       { show_error( "Not enough memory." );
-        LZ_decompress_close( decoder ); return false; }
+        LZ_decompress_close( decoder ); fatal = true; return 2; }
     if( LZ_decompress_write( decoder, buf, rd ) != rd )
       internal_error( "library error (LZ_decompress_write)." );
-    if( !archive_read( infd, buf, size ) ) return false;
-    if( verify_ustar_chksum( buf ) || block_is_zero( buf, size ) ) return true;
-    show_error( "This does not look like a tar archive." );
-    show_error( "Skipping to next header." );
-    gretval = 2;
-    if( LZ_decompress_sync_to_member( decoder ) < 0 )
-      internal_error( "library error (LZ_decompress_sync_to_member)." );
+    const int res = archive_read( infd, buf, size, sizep );
+    if( res != 0 ) { if( res == 2 ) fatal = true; return res; }
+    if( verify_ustar_chksum( buf ) || block_is_zero( buf, size ) ) return 0;
+    show_error( "This does not look like a POSIX tar.lz archive." );
+    fatal = true; return 2;
     }
 
   if( !decoder )					// uncompressed
-    { if( readblock( infd, buf, size ) == size ) return true;
-      show_error( "Archive ends unexpectedly." ); return false; }
+    {
+    const int rd = readblock( infd, buf, size ); if( rd == size ) return 0;
+    if( sizep ) *sizep = rd;
+    show_error( "Archive ends unexpectedly." ); fatal = true; return 2;
+    }
   const int ibuf_size = 16384;
   uint8_t ibuf[ibuf_size];
   int sz = 0;
   while( sz < size )
     {
-    if( !at_eof && LZ_decompress_write_size( decoder ) > 0 )
+    const int rd = LZ_decompress_read( decoder, buf + sz, size - sz );
+    if( rd < 0 )
+      {
+      if( LZ_decompress_sync_to_member( decoder ) < 0 )
+        internal_error( "library error (LZ_decompress_sync_to_member)." );
+      skip_warn(); gretval = 2; return 1;
+      }
+    if( rd == 0 && LZ_decompress_finished( decoder ) == 1 )
+     { LZ_decompress_close( decoder );
+       show_error( "Archive ends unexpectedly." ); fatal = true; return 2; }
+    sz += rd; if( sizep ) *sizep = sz;
+    if( sz == size && LZ_decompress_finished( decoder ) == 1 &&
+        LZ_decompress_close( decoder ) < 0 )
+      { show_error( "LZ_decompress_close failed." ); fatal = true; return 2; }
+    if( sz < size && !at_eof && LZ_decompress_write_size( decoder ) > 0 )
       {
       const int rsize = std::min( ibuf_size, LZ_decompress_write_size( decoder ) );
       const int rd = readblock( infd, ibuf, rsize );
@@ -172,27 +176,12 @@ bool archive_read( const int infd, uint8_t * const buf, const int size )
         {
         at_eof = true; LZ_decompress_finish( decoder );
         if( errno )
-          { show_error( "Error reading archive", errno ); return false; }
+          { show_error( "Error reading archive", errno ); fatal = true;
+            return 2; }
         }
       }
-    const int rd = LZ_decompress_read( decoder, buf + sz, size - sz );
-    if( rd < 0 )
-      {
-      show_error( "Skipping to next header." );
-      gretval = 2;
-      if( LZ_decompress_sync_to_member( decoder ) < 0 )
-        internal_error( "library error (LZ_decompress_sync_to_member)." );
-      continue;
-      }
-    if( rd == 0 && LZ_decompress_finished( decoder ) == 1 )
-     { LZ_decompress_close( decoder );
-       show_error( "Archive ends unexpectedly." ); return false; }
-    sz += rd;
-    if( sz == size && LZ_decompress_finished( decoder ) == 1 &&
-        LZ_decompress_close( decoder ) < 0 )
-      { show_error( "LZ_decompress_close failed." ); return false; }
     }
-  return true;
+  return 0;
   }
 
 
@@ -251,55 +240,44 @@ const char * user_group_string( const Tar_header header )
   }
 
 
-const char * link_string( const Tar_header header )
-  {
-  enum { bufsize = 9 + linkname_l + 1 };
-  static char buf[bufsize];
-  const Typeflag typeflag = (Typeflag)header[typeflag_o];
-
-  if( typeflag == tf_link )
-    snprintf( buf, bufsize, " link to %.100s", header + linkname_o );
-  else if( typeflag == tf_symlink )
-    snprintf( buf, bufsize, " -> %.100s", header + linkname_o );
-  else buf[0] = 0;
-  return buf;
-  }
-
-
-void show_member_name( const char * const filename, const Tar_header header,
+void show_member_name( const Extended & extended, const Tar_header header,
                        const int vlevel )
   {
   if( verbosity < vlevel ) return;
   if( verbosity > vlevel )
     {
     const time_t mtime = strtoull( header + mtime_o, 0, 8 );	// 33 bits
-    struct tm * tm = localtime( &mtime );
-    std::printf( "%s %s %9llu %4d-%02u-%02u %02u:%02u %s%s\n",
+    const struct tm * const tm = localtime( &mtime );
+    const Typeflag typeflag = (Typeflag)header[typeflag_o];
+    const bool islink = ( typeflag == tf_link || typeflag == tf_symlink );
+    const char * const link_string = !islink ? "" :
+                         ( ( typeflag == tf_link ) ? " link to " : " -> " );
+    std::printf( "%s %s %9llu %4d-%02u-%02u %02u:%02u %s%s%s\n",
                  mode_string( header ), user_group_string( header ),
-                 strtoull( header + size_o, 0, 8 ), 1900 + tm->tm_year,
-                 1 + tm->tm_mon, tm->tm_mday, tm->tm_hour, tm->tm_min,
-                 filename, link_string( header ) );
+                 extended.size, 1900 + tm->tm_year, 1 + tm->tm_mon,
+                 tm->tm_mday, tm->tm_hour, tm->tm_min, extended.path.c_str(),
+                 link_string, !islink ? "" : extended.linkpath.c_str() );
     }
-  else std::printf( "%s\n", filename );
+  else std::printf( "%s\n", extended.path.c_str() );
   std::fflush( stdout );
   }
 
 
-int list_member( const int infd, const char * const filename,
-                 const unsigned long long file_size, const Tar_header header,
-                 const bool skip )
+int list_member( const int infd, const Extended & extended,
+                 const Tar_header header, const bool skip )
   {
-  if( !skip ) show_member_name( filename, header, 0 );
+  if( !skip ) show_member_name( extended, header, 0 );
 
   const unsigned bufsize = 32 * header_size;
   uint8_t buf[bufsize];
-  unsigned long long rest = file_size;
-  const int rem = file_size % header_size;
+  unsigned long long rest = extended.size;
+  const int rem = extended.size % header_size;
   const int padding = rem ? header_size - rem : 0;
   while( rest > 0 )
     {
     const int rsize = ( rest >= bufsize ) ? bufsize : rest + padding;
-    if( !archive_read( infd, buf, rsize ) ) return 2;
+    const int ret = archive_read( infd, buf, rsize );
+    if( ret != 0 ) { if( ret == 2 ) return 2; else break; }
     if( rest < bufsize ) break;
     rest -= rsize;
     }
@@ -317,13 +295,14 @@ bool contains_dotdot( const char * const filename )
   }
 
 
-int extract_member( const int infd, const char * const filename,
-                    const unsigned long long file_size, const Tar_header header )
+int extract_member( const int infd, const Extended & extended,
+                    const Tar_header header, const bool keep_damaged )
   {
+  const char * const filename = extended.path.c_str();
   if( contains_dotdot( filename ) )
     {
     show_file_error( filename, "Contains a '..' component, skipping." );
-    return list_member( infd, filename, file_size, header, true );
+    return list_member( infd, extended, header, true );
     }
   const mode_t mode = strtoul( header + mode_o, 0, 8 );		// 12 bits
   const time_t mtime = strtoull( header + mtime_o, 0, 8 );	// 33 bits
@@ -331,7 +310,7 @@ int extract_member( const int infd, const char * const filename,
   const bool islink = ( typeflag == tf_link || typeflag == tf_symlink );
   int outfd = -1;
 
-  show_member_name( filename, header, 1 );
+  show_member_name( extended, header, 1 );
   std::remove( filename );
   make_path( filename );
   switch( typeflag )
@@ -345,14 +324,12 @@ int extract_member( const int infd, const char * const filename,
     case tf_link:
     case tf_symlink:
       {
-      char linkname[linkname_l+1];
-      std::memcpy( linkname, header + linkname_o, linkname_l );
-      linkname[linkname_l] = 0;
+      const char * const linkname = extended.linkpath.c_str();
 /*      if( contains_dotdot( linkname ) )
         {
         show_file_error( filename,
           "Link destination contains a '..' component, skipping." );
-        return list_member( infd, filename, file_size, header, false );
+        return list_member( infd, extended, header, false );
         }*/
       const bool hard = typeflag == tf_link;
       if( ( hard && link( linkname, filename ) != 0 ) ||
@@ -410,15 +387,25 @@ int extract_member( const int infd, const char * const filename,
 
   const unsigned bufsize = 32 * header_size;
   uint8_t buf[bufsize];
-  unsigned long long rest = file_size;
-  const int rem = file_size % header_size;
+  unsigned long long rest = extended.size;
+  const int rem = extended.size % header_size;
   const int padding = rem ? header_size - rem : 0;
   while( rest > 0 )
     {
     const int rsize = ( rest >= bufsize ) ? bufsize : rest + padding;
-    if( !archive_read( infd, buf, rsize ) )
-      { if( outfd >= 0 ) { close( outfd ); std::remove( filename ); }
-        return 2; }
+    int rd;
+    const int ret = archive_read( infd, buf, rsize, &rd );
+    if( ret != 0 )
+      {
+      if( outfd >= 0 )
+        {
+        if( keep_damaged )
+          { writeblock( outfd, buf, std::min( rest, (unsigned long long)rd ) );
+            close( outfd ); }
+        else { close( outfd ); std::remove( filename ); }
+        }
+      if( ret == 2 ) return 2; else return 0;
+      }
     const int wsize = ( rest >= bufsize ) ? bufsize : rest;
     if( outfd >= 0 && writeblock( outfd, buf, wsize ) != wsize )
       { show_file_error( filename, "Error writing file", errno ); return 2; }
@@ -437,6 +424,7 @@ int extract_member( const int infd, const char * const filename,
   }
 
 
+// Removes any amount of leading "./" and '/' strings.
 const char * remove_leading_slash( const char * const filename )
   {
   static bool first_post = true;
@@ -479,73 +467,173 @@ bool compare_tslash( const char * const name1, const char * const name2 )
 } // end namespace
 
 
+bool Extended::parse( const int infd, const Tar_header header,
+                      const bool permissive )
+  {
+  const unsigned long long edsize = strtoull( header + size_o, 0, 8 );
+  const unsigned long long bufsize = round_up( edsize );
+  if( bufsize == 0 || edsize == 0 || edsize >= 1ULL << 33 )
+    return false;				// overflow or no extended data
+  char * const buf = new char[bufsize];		// extended records buffer
+  if( archive_read( infd, (uint8_t *)buf, bufsize ) != 0 ) goto error;
+  for( unsigned long long pos = 0; pos < edsize; )	// parse records
+    {
+    char * tail;
+    const unsigned long long rsize = strtoull( buf + pos, &tail, 10 );
+    if( rsize == 0 || rsize > edsize - pos || tail[0] != ' ' ||
+        buf[pos+rsize-1] != '\n' ) goto error;
+    ++tail;	// point to keyword
+    // length of (keyword + '=' + value) without the final newline
+    const unsigned long long rest = ( buf + pos + rsize - 1 ) - tail;
+    if( rest > 5 && std::memcmp( tail, "path=", 5 ) == 0 )
+      { if( path.size() && !permissive ) goto error;
+        path.assign( tail + 5, rest - 5 ); }
+    else if( rest > 9 && std::memcmp( tail, "linkpath=", 9 ) == 0 )
+      { if( linkpath.size() && !permissive ) goto error;
+        linkpath.assign( tail + 9, rest - 9 ); }
+    else if( rest > 5 && std::memcmp( tail, "size=", 5 ) == 0 )
+      {
+      if( size != 0 && !permissive ) goto error;
+      size = 0;
+      for( unsigned long long i = 5; i < rest; ++i )
+        {
+        if( tail[i] < '0' || tail[i] > '9' ) goto error;
+        const unsigned long long prev = size;
+        size = size * 10 + ( tail[i] - '0' );
+        if( size < prev ) goto error;		// overflow
+        }
+      if( size < 1ULL << 33 ) goto error;	// size fits in ustar header
+      }
+    else if( rest > 10 && std::memcmp( tail, "GNU.crc32=", 10 ) == 0 )
+      {
+      if( crc_present && !permissive ) goto error;
+      if( rsize != 22 ) goto error;
+      char * t;
+      const uint32_t stored_crc = strtoul( tail + 10, &t, 16 );
+      if( t - tail - 10 != 8 || t[0] != '\n' ) goto error;
+      const uint32_t computed_crc =
+        crc32c.windowed_crc( (const uint8_t *)buf, pos + rsize - 9, edsize );
+      crc_present = true;
+      if( stored_crc != computed_crc ) goto error;
+      }
+    pos += rsize;
+    }
+  delete[] buf;
+  return true;
+error:
+  delete[] buf;
+  return false;
+  }
+
+
 int decode( const std::string & archive_name, const Arg_parser & parser,
-            const int filenames, const bool listing )
+            const int filenames, const bool keep_damaged, const bool listing,
+            const bool missing_crc, const bool permissive )
   {
   const int infd = archive_name.size() ?
                    open_instream( archive_name ) : STDIN_FILENO;
   if( infd < 0 ) return 1;
 
+  // execute -C options and mark filenames to be extracted or listed
   std::vector< bool > name_pending( parser.arguments(), false );
   for( int i = 0; i < parser.arguments(); ++i )
     {
     const int code = parser.code( i );
     if( code == 'C' && !listing )
       {
-      const char * const filename = parser.argument( i ).c_str();
-      if( chdir( filename ) != 0 )
-        { show_file_error( filename, "Error changing working directory", errno );
+      const char * const dir = parser.argument( i ).c_str();
+      if( chdir( dir ) != 0 )
+        { show_file_error( dir, "Error changing working directory", errno );
           return 1; }
       }
     if( !code ) name_pending[i] = true;
     }
 
+  has_lz_ext =
+    ( archive_name.size() > 3 &&
+      archive_name.compare( archive_name.size() - 3, 3, ".lz" ) == 0 ) ||
+    ( archive_name.size() > 4 &&
+      archive_name.compare( archive_name.size() - 4, 4, ".tlz" ) == 0 );
+  Extended extended;		// metadata from extended records
   int retval = 0;
-  bool skipping = false;
+  bool prev_extended = false;	// prev header was extended
   while( true )			// process one member per iteration
     {
     uint8_t buf[header_size];
-    if( !archive_read( infd, buf, header_size ) ) return 2;
-    if( !verify_ustar_chksum( buf ) )
+    const int ret = archive_read( infd, buf, header_size );
+    if( ret == 2 ) return 2;
+    if( ret != 0 || !verify_ustar_chksum( buf ) )
       {
-      if( block_is_zero( buf, header_size ) ) break;
-      gretval = 2;
-      if( !skipping )
-        { skipping = true; show_error( "Skipping to next header." ); }
-      continue;
+      if( ret == 0 && block_is_zero( buf, header_size ) ) break;	// EOF
+      skip_warn(); gretval = 2; continue;
       }
-    skipping = false;
+    skip_warn( true );		// reset warning
 
     const char * const header = (const char *)buf;
-    enum { max_filename_size = prefix_l + 1 + name_l + 1 };
-    char stored_name[max_filename_size];
-    int len = 0;
-    while( len < prefix_l && header[prefix_o+len] )
-      { stored_name[len] = header[prefix_o+len]; ++len; }
-    if( len && header[name_o] ) stored_name[len++] = '/';
-    for( int i = 0; i < name_l && header[name_o+i]; ++i )
-      { stored_name[len] = header[name_o+i]; ++len; }
-    while( len > 0 && stored_name[len-1] == '/' ) --len;	// trailing '/'
-    stored_name[len] = 0;
-    const char * const filename = remove_leading_slash( stored_name );
+    const Typeflag typeflag = (Typeflag)header[typeflag_o];
+    if( typeflag == tf_extended )
+      {
+      if( prev_extended && !permissive )
+        { show_error( "Format violation: consecutive extended headers found."
+                      /*" Use --permissive."*/, 0, true ); return 2; }
+      if( !extended.parse( infd, header, permissive ) )
+        { show_error( "Error in extended records. Skipping to next header." );
+          extended.reset(); gretval = 2; }
+      else if( !extended.crc_present && missing_crc )
+        { show_error( "Missing CRC in extended records.", 0, true ); return 2; }
+      prev_extended = true;
+      continue;
+      }
+    prev_extended = false;
+
+    if( extended.linkpath.empty() )
+      {
+      for( int i = 0; i < linkname_l && header[linkname_o+i]; ++i )
+        extended.linkpath += header[linkname_o+i];
+      while( extended.linkpath.size() > 1 &&		// trailing '/'
+             extended.linkpath[extended.linkpath.size()-1] == '/' )
+        extended.linkpath.resize( extended.linkpath.size() - 1 );
+      }
+
+    if( extended.path.empty() )
+      {
+      char stored_name[prefix_l+1+name_l+1];
+      int len = 0;
+      while( len < prefix_l && header[prefix_o+len] )
+        { stored_name[len] = header[prefix_o+len]; ++len; }
+      if( len && header[name_o] ) stored_name[len++] = '/';
+      for( int i = 0; i < name_l && header[name_o+i]; ++i )
+        { stored_name[len] = header[name_o+i]; ++len; }
+      while( len > 0 && stored_name[len-1] == '/' ) --len;	// trailing '/'
+      stored_name[len] = 0;
+      extended.path = remove_leading_slash( stored_name );
+      }
+    const char * const filename = extended.path.c_str();
 
     bool skip = filenames > 0;
     if( skip )
       for( int i = 0; i < parser.arguments(); ++i )
-        if( parser.code( i ) == 0 &&
-            ( compare_prefix_dir( parser.argument( i ).c_str(), filename ) ||
-              compare_tslash( filename, parser.argument( i ).c_str() ) ) )
-          { skip = false; name_pending[i] = false; break; }
+        if( parser.code( i ) == 0 )
+          {
+          const char * const name =
+            remove_leading_slash( parser.argument( i ).c_str() );
+          if( compare_prefix_dir( name, filename ) ||
+              compare_tslash( name, filename ) )
+            { skip = false; name_pending[i] = false; break; }
+          }
+
+    if( extended.size == 0 &&
+        ( typeflag == tf_regular || typeflag == tf_hiperf ) )
+      extended.size = strtoull( header + size_o, 0, 8 );
 
-    const Typeflag typeflag = (Typeflag)header[typeflag_o];
-    const unsigned long long file_size =
-      ( typeflag == tf_regular || typeflag == tf_hiperf ) ?
-        strtoull( header + size_o, 0, 8 ) : 0;
     if( listing || skip )
-      retval = list_member( infd, filename, file_size, header, skip );
+      retval = list_member( infd, extended, header, skip );
     else
-      retval = extract_member( infd, filename, file_size, header );
-    if( retval ) return retval;
+      retval = extract_member( infd, extended, header, keep_damaged );
+    extended.reset();
+    if( retval )
+      { show_error( "Error is not recoverable: exiting now." );
+        return retval; }
     }
 
   for( int i = 0; i < parser.arguments(); ++i )