Hi,
extracting a sparse file to a filesystem like vfat that does not
support sparse files results in an incomplete output file.
See:
https://bugzilla.redhat.com/bugzilla/show_bug.cgi?id=179507
What do you think about attached patch?
--- tar-1.15.1/src/sparse.c.vfatTruncate 2006-02-02 13:38:18.000000000 -0500
+++ tar-1.15.1/src/sparse.c 2006-02-02 14:06:37.000000000 -0500
@@ -345,6 +345,8 @@
sparse_extract_region (struct tar_sparse_file *file, size_t i)
{
size_t write_size;
+ struct stat st;
+ off_t oldoff;
if (!lseek_or_error (file, file->stat_info->sparse_map[i].offset))
return false;
@@ -354,8 +356,20 @@
if (write_size == 0)
{
/* Last block of the file is a hole */
- if (file->seekable && sys_truncate (file->fd))
+ if (file->seekable && sys_truncate (file->fd)) {
truncate_warn (file->stat_info->orig_file_name);
+
+ /* wrapper around ftruncate:
+ * ftruncate may fail to grow the size of a file with some OS and filesystem
+ * combinations. Linux and vfat/fat is one example. If this is the case do
+ * a write to grow the file to the desired length.
+ */
+ off_t length = lseek (file->fd, (off_t) 0, SEEK_CUR);
+ if( (length >= 0) && (fstat( file->fd, &st ) != -1) && (st.st_size < length) ) {
+ lseek( file->fd, length - 1, SEEK_SET);
+ write( file->fd, '\0', 1);
+ }
+ }
}
else while (write_size > 0)
{
_______________________________________________
Bug-tar mailing list
[email protected]
http://lists.gnu.org/mailman/listinfo/bug-tar
