[nginx] Mail: optimized discarding invalid SMTP commands.

[Maxim Dounin]

details:   https://hg.nginx.org/nginx/rev/ba8a8299b904
branches:  
changeset: 7837:ba8a8299b904
user:      Maxim Dounin <mdounin at mdounin.ru>
date:      Wed May 19 03:13:17 2021 +0300
description:
Mail: optimized discarding invalid SMTP commands.

There is no need to scan buffer from s->buffer->pos, as we already scanned
the buffer till "p" and wasn't able to find an LF.

There is no real need for this change in SMTP, since it is at most a
microoptimization of a non-common code path.  Similar code in IMAP, however,
will have to start scanning from "p" to be correct, since there can be
newlines in IMAP literals.

diffstat:

 src/mail/ngx_mail_parse.c |  2 +-
 1 files changed, 1 insertions(+), 1 deletions(-)

diffs (12 lines):

diff -r 6a81d96d3733 -r ba8a8299b904 src/mail/ngx_mail_parse.c
--- a/src/mail/ngx_mail_parse.c	Wed May 19 03:13:15 2021 +0300
+++ b/src/mail/ngx_mail_parse.c	Wed May 19 03:13:17 2021 +0300
@@ -843,7 +843,7 @@ invalid:
 
     /* skip invalid command till LF */
 
-    for (p = s->buffer->pos; p < s->buffer->last; p++) {
+    for ( /* void */ ; p < s->buffer->last; p++) {
         if (*p == LF) {
             s->state = sw_start;
             s->buffer->pos = p + 1;