From: Dave Rodgman <dave.rodgman@arm.com>
To: "C. Masloch" <pushbx@ulukai.org>,
"linux-doc@vger.kernel.org" <linux-doc@vger.kernel.org>
Cc: "linux-kernel@vger.kernel.org" <linux-kernel@vger.kernel.org>,
Jonathan Corbet <corbet@lwn.net>, Willy Tarreau <w@1wt.eu>,
Andrew Morton <akpm@linux-foundation.org>
Subject: Re: [PATCH 1/2] docs: lzo: fix first byte interpretation off-by-one
Date: Fri, 22 May 2020 15:22:29 +0000 [thread overview]
Message-ID: <ED8A0242-10D3-4280-815F-BB38AB80251D@arm.com> (raw)
In-Reply-To: <20200522141040.1353769-1-pushbx@ulukai.org>
Your update looks correct to me, thanks.
Dave
On 22/05/2020, 15:11, "C. Masloch" <pushbx@ulukai.org> wrote:
There was an error in the description of the initial byte's
interpretation. While "18..21" was listed as "copy 0..3 literals",
it should actually be interpreted as "copy 1..4 literals".
The "byte - 17" part is correct. 17 would encode copying "zero"
literals, but does not occur. 18 encodes copying 1 literal,
19 then 2 literals, 20 for 3 literals, 21 for 4 literals.
The description should read "18..21" as "copy 1..4 literals".
Likewise, 22 indicates "copying 5 literals", not "4 literals".
However, the state is indeed always set to "byte - 17" (which
for 21 results in 4 too).
Signed-off-by: C. Masloch <pushbx@ulukai.org>
---
Documentation/lzo.txt | 6 +++---
1 file changed, 3 insertions(+), 3 deletions(-)
diff --git a/Documentation/lzo.txt b/Documentation/lzo.txt
index ca9833289..f839d104d 100644
--- a/Documentation/lzo.txt
+++ b/Documentation/lzo.txt
@@ -108,12 +108,12 @@ Byte sequences
(version 1 only).
Otherwise, the bitstream version is 0.
- 18..21 : copy 0..3 literals
- state = (byte - 17) = 0..3 [ copy <state> literals ]
+ 18..21 : copy 1..4 literals
+ state = (byte - 17) = 1..4 [ copy <state> literals ]
skip byte
22..255 : copy literal string
- length = (byte - 17) = 4..238
+ length = (byte - 17) = 5..238
state = 4 [ don't copy extra literals ]
skip byte
--
2.26.2
IMPORTANT NOTICE: The contents of this email and any attachments are confidential and may also be privileged. If you are not the intended recipient, please notify the sender immediately and do not disclose the contents to any other person, use it for any purpose, or store or copy the information in any medium. Thank you.
prev parent reply other threads:[~2020-05-22 15:22 UTC|newest]
Thread overview: 4+ messages / expand[flat|nested] mbox.gz Atom feed top
2020-05-22 14:10 [PATCH 1/2] docs: lzo: fix first byte interpretation off-by-one C. Masloch
2020-05-22 14:10 ` [PATCH 2/2] docs: lzo: fix incorrect statement about distance zero for EOS C. Masloch
2020-05-22 15:22 ` Dave Rodgman
2020-05-22 15:22 ` Dave Rodgman [this message]
Reply instructions:
You may reply publicly to this message via plain-text email
using any one of the following methods:
* Save the following mbox file, import it into your mail client,
and reply-to-all from there: mbox
Avoid top-posting and favor interleaved quoting:
https://en.wikipedia.org/wiki/Posting_style#Interleaved_style
* Reply using the --to, --cc, and --in-reply-to
switches of git-send-email(1):
git send-email \
--in-reply-to=ED8A0242-10D3-4280-815F-BB38AB80251D@arm.com \
--to=dave.rodgman@arm.com \
--cc=akpm@linux-foundation.org \
--cc=corbet@lwn.net \
--cc=linux-doc@vger.kernel.org \
--cc=linux-kernel@vger.kernel.org \
--cc=pushbx@ulukai.org \
--cc=w@1wt.eu \
/path/to/YOUR_REPLY
https://kernel.org/pub/software/scm/git/docs/git-send-email.html
* If your mail client supports setting the In-Reply-To header
via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line
before the message body.
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox;
as well as URLs for NNTP newsgroup(s).