|
From: Anton A. <ai...@ca...> - 2006-10-29 07:55:51
|
This is b0rked, please revert it ASAP. You cannot use memmove().
Please do not meddle with code you do not understand. (Given your log
message you clearly do not understand it...)
Anton
On Sun, 29 Oct 2006, Yuval wrote:
>
> Changes by: uvman
>
> Update of /cvs/linux-ntfs/ntfsprogs/libntfs
> In directory delta357:/tmp/cvs-serv11764/libntfs
>
> Modified Files:
> compress.c
> Log Message:
> memmove() already deals with overlap, is optimized, is ANSI C and only takes one line to call.
>
> Index: compress.c
> ===================================================================
> RCS file: /cvs/linux-ntfs/ntfsprogs/libntfs/compress.c,v
> retrieving revision 1.16
> retrieving revision 1.17
> diff -u -p -r1.16 -r1.17
> --- compress.c 26 Oct 2006 19:10:05 -0000 1.16
> +++ compress.c 28 Oct 2006 23:15:44 -0000 1.17
> @@ -166,7 +166,7 @@ do_next_tag:
> tag = *cb++;
> /* Parse the eight tokens described by the tag. */
> for (token = 0; token < 8; token++, tag >>= 1) {
> - u16 lg, pt, length, max_non_overlap;
> + u16 lg, pt, length;
> register u16 i;
> u8 *dest_back_addr;
>
> @@ -214,27 +214,8 @@ do_next_tag:
> /* Verify destination is in range. */
> if (dest + length > dest_sb_end)
> goto return_overflow;
> - /* The number of non-overlapping bytes. */
> - max_non_overlap = dest - dest_back_addr;
> - if (length <= max_non_overlap) {
> - /* The byte sequence doesn't overlap, just copy it. */
> - memcpy(dest, dest_back_addr, length);
> - /* Advance destination pointer. */
> - dest += length;
> - } else {
> - /*
> - * The byte sequence does overlap, copy non-overlapping
> - * part and then do a slow byte by byte copy for the
> - * overlapping part. Also, advance the destination
> - * pointer.
> - */
> - memcpy(dest, dest_back_addr, max_non_overlap);
> - dest += max_non_overlap;
> - dest_back_addr += max_non_overlap;
> - length -= max_non_overlap;
> - while (length--)
> - *dest++ = *dest_back_addr++;
> - }
> + /* memmove() is safe with overlapping blocks. */
> + memmove(dest, dest_back_addr, length);
> /* Advance source position and continue with the next token. */
> cb += 2;
> }
>
--
Anton Altaparmakov <aia21 at cam.ac.uk> (replace at with @)
Unix Support, Computing Service, University of Cambridge, CB2 3QH, UK
Linux NTFS maintainer, http://www.linux-ntfs.org/
|
