+ union block *pointer = find_next_block ();
+ memset (pointer->buffer, 0, BLOCKSIZE);
+ set_next_block_after (pointer);
+ pointer = find_next_block ();
+ memset (pointer->buffer, 0, available_space_after (pointer));
+ set_next_block_after (pointer);
+}
+
+/* Write a "private" header */
+union block *
+start_private_header (const char *name, size_t size)
+{
+ time_t t;
+ union block *header = find_next_block ();
+
+ memset (header->buffer, 0, sizeof (union block));
+
+ tar_name_copy_str (header->header.name, name, NAME_FIELD_SIZE);
+ OFF_TO_CHARS (size, header->header.size);
+
+ time (&t);
+ TIME_TO_CHARS (t, header->header.mtime);
+ MODE_TO_CHARS (S_IFREG|S_IRUSR|S_IWUSR|S_IRGRP|S_IROTH, header->header.mode);
+ UID_TO_CHARS (getuid (), header->header.uid);
+ GID_TO_CHARS (getgid (), header->header.gid);
+ MAJOR_TO_CHARS (0, header->header.devmajor);
+ MINOR_TO_CHARS (0, header->header.devminor);
+ strncpy (header->header.magic, TMAGIC, TMAGLEN);
+ strncpy (header->header.version, TVERSION, TVERSLEN);
+ return header;
+}
+
+/* Create a new header and store there at most NAME_FIELD_SIZE bytes of
+ the file name */
+
+static union block *
+write_short_name (struct tar_stat_info *st)
+{
+ union block *header = find_next_block ();
+ memset (header->buffer, 0, sizeof (union block));
+ tar_name_copy_str (header->header.name, st->file_name, NAME_FIELD_SIZE);
+ return header;
+}
+
+#define FILL(field,byte) do { \
+ memset(field, byte, sizeof(field)-1); \
+ (field)[sizeof(field)-1] = 0; \
+} while (0)
+
+/* Write a GNUTYPE_LONGLINK or GNUTYPE_LONGNAME block. */
+static void
+write_gnu_long_link (struct tar_stat_info *st, const char *p, char type)
+{
+ size_t size = strlen (p) + 1;
+ size_t bufsize;
+ union block *header;
+ char *tmpname;
+
+ header = start_private_header ("././@LongLink", size);
+ FILL(header->header.mtime, '0');
+ FILL(header->header.mode, '0');
+ FILL(header->header.uid, '0');
+ FILL(header->header.gid, '0');
+ FILL(header->header.devmajor, 0);
+ FILL(header->header.devminor, 0);
+ uid_to_uname (0, &tmpname);
+ UNAME_TO_CHARS (tmpname, header->header.uname);
+ free (tmpname);
+ gid_to_gname (0, &tmpname);
+ GNAME_TO_CHARS (tmpname, header->header.gname);
+ free (tmpname);
+
+ strcpy (header->header.magic, OLDGNU_MAGIC);
+ header->header.typeflag = type;
+ finish_header (st, header, -1);
+
+ header = find_next_block ();
+
+ bufsize = available_space_after (header);
+
+ while (bufsize < size)
+ {
+ memcpy (header->buffer, p, bufsize);
+ p += bufsize;
+ size -= bufsize;
+ set_next_block_after (header + (bufsize - 1) / BLOCKSIZE);
+ header = find_next_block ();
+ bufsize = available_space_after (header);
+ }
+ memcpy (header->buffer, p, size);
+ memset (header->buffer + size, 0, bufsize - size);
+ set_next_block_after (header + (size - 1) / BLOCKSIZE);
+}
+
+static size_t
+split_long_name (const char *name, size_t length)
+{
+ size_t i;
+
+ if (length > PREFIX_FIELD_SIZE)
+ length = PREFIX_FIELD_SIZE + 1;
+ for (i = length - 1; i > 0; i--)
+ if (ISSLASH (name[i]))
+ break;
+ return i;
+}
+
+static union block *
+write_ustar_long_name (const char *name)
+{
+ size_t length = strlen (name);
+ size_t i;
+ union block *header;
+
+ if (length > PREFIX_FIELD_SIZE + NAME_FIELD_SIZE + 1)
+ {
+ ERROR ((0, 0, _("%s: file name is too long (max %d); not dumped"),
+ quotearg_colon (name),
+ PREFIX_FIELD_SIZE + NAME_FIELD_SIZE + 1));
+ return NULL;
+ }
+
+ i = split_long_name (name, length);
+ if (i == 0 || length - i - 1 > NAME_FIELD_SIZE)
+ {
+ ERROR ((0, 0,
+ _("%s: file name is too long (cannot be split); not dumped"),
+ quotearg_colon (name)));
+ return NULL;
+ }
+
+ header = find_next_block ();
+ memset (header->buffer, 0, sizeof (header->buffer));
+ memcpy (header->header.prefix, name, i);
+ memcpy (header->header.name, name + i + 1, length - i - 1);
+
+ return header;
+}
+
+/* Write a long link name, depending on the current archive format */
+static void
+write_long_link (struct tar_stat_info *st)
+{
+ switch (archive_format)
+ {
+ case POSIX_FORMAT:
+ xheader_store ("linkpath", st, NULL);
+ break;
+
+ case V7_FORMAT: /* old V7 tar format */
+ case USTAR_FORMAT:
+ case STAR_FORMAT:
+ ERROR ((0, 0,
+ _("%s: link name is too long; not dumped"),
+ quotearg_colon (st->link_name)));
+ break;
+
+ case OLDGNU_FORMAT:
+ case GNU_FORMAT:
+ write_gnu_long_link (st, st->link_name, GNUTYPE_LONGLINK);
+ break;
+
+ default:
+ abort(); /*FIXME*/
+ }
+}
+
+static union block *
+write_long_name (struct tar_stat_info *st)
+{
+ switch (archive_format)
+ {
+ case POSIX_FORMAT:
+ xheader_store ("path", st, NULL);
+ break;
+
+ case V7_FORMAT:
+ if (strlen (st->file_name) > NAME_FIELD_SIZE-1)