[PATCH 0/5] net: use semicolons rather than commas to separate statements

[PATCH 0/5] net: use semicolons rather than commas to separate statements

[Julia Lawall]

These patches replace commas by semicolons.  Commas introduce
unnecessary variability in the code structure and are hard to see.
This was done using the Coccinelle semantic patch
(http://coccinelle.lip6.fr/) shown below.

This semantic patch ensures that commas inside for loop headers will
not be transformed.  It also doesn't touch macro definitions.

Coccinelle ensures that braces are added as needed when a
single-statement branch turns into a multi-statement one.

This semantic patch has a few false positives, for variable
delcarations such as:

LIST_HEAD(x), *y;

The semantic patch could be improved to avoid these, but for the
moment they have been removed manually (2 occurrences).

// <smpl>
@initialize:ocaml@
@@

let infunction p =
  (* avoid macros *)
  (List.hd p).current_element <> "something_else"

let combined p1 p2 =
  (List.hd p1).line_end = (List.hd p2).line ||
  (((List.hd p1).line_end < (List.hd p2).line) &&
   ((List.hd p1).col < (List.hd p2).col))

@bad@
statement S;
declaration d;
position p;
@@

S@p
d

// special cases where newlines are needed (hope for no more than 5)
@@
expression e1,e2;
statement S;
position p != bad.p;
position p1;
position p2 :
    script:ocaml(p1) { infunction p1 && combined p1 p2 };
@@

- e1@p1,@S@p e2@p2;
+ e1; e2;

@@
expression e1,e2;
statement S;
position p != bad.p;
position p1;
position p2 :
    script:ocaml(p1) { infunction p1 && combined p1 p2 };
@@

- e1@p1,@S@p e2@p2;
+ e1; e2;

@@
expression e1,e2;
statement S;
position p != bad.p;
position p1;
position p2 :
    script:ocaml(p1) { infunction p1 && combined p1 p2 };
@@

- e1@p1,@S@p e2@p2;
+ e1; e2;

@@
expression e1,e2;
statement S;
position p != bad.p;
position p1;
position p2 :
    script:ocaml(p1) { infunction p1 && combined p1 p2 };
@@

- e1@p1,@S@p e2@p2;
+ e1; e2;

@@
expression e1,e2;
statement S;
position p != bad.p;
position p1;
position p2 :
    script:ocaml(p1) { infunction p1 && combined p1 p2 };
@@

- e1@p1,@S@p e2@p2;
+ e1; e2;

@r@
expression e1,e2;
statement S;
position p != bad.p;
@@

e1 ,@S@p e2;

@@
expression e1,e2;
position p1;
position p2 :
    script:ocaml(p1) { infunction p1 && not(combined p1 p2) };
statement S;
position r.p;
@@

e1@p1
-,@S@p
+;
e2@p2
... when any
// </smpl>

---

 net/ipv4/tcp_input.c       |    3 ++-
 net/ipv4/tcp_vegas.c       |    8 ++++----
 net/ipv6/calipso.c         |    2 +-
 net/mac80211/debugfs_sta.c |    2 +-
 net/rxrpc/recvmsg.c        |    2 +-
 net/tls/tls_main.c         |    2 +-
 6 files changed, 10 insertions(+), 9 deletions(-)

[PATCH 4/5] net/ipv6: use semicolons rather than commas to separate statements

[Julia Lawall]

Replace commas with semicolons.  Commas introduce unnecessary
variability in the code structure and are hard to see.  What is done
is essentially described by the following Coccinelle semantic patch
(http://coccinelle.lip6.fr/):

// <smpl>
@@ expression e1,e2; @@
e1
-,
+;
e2
... when any
// </smpl>

Signed-off-by: Julia Lawall <Julia.Lawall@inria.fr>

---
 net/ipv6/calipso.c |    2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/net/ipv6/calipso.c b/net/ipv6/calipso.c
index 8d3f66c310db..78f766019b7e 100644
--- a/net/ipv6/calipso.c
+++ b/net/ipv6/calipso.c
@@ -761,7 +761,7 @@ static int calipso_genopt(unsigned char *buf, u32 start, u32 buf_len,
 	calipso[1] = len - 2;
 	*(__be32 *)(calipso + 2) = htonl(doi_def->doi);
 	calipso[6] = (len - CALIPSO_HDR_LEN) / 4;
-	calipso[7] = secattr->attr.mls.lvl,
+	calipso[7] = secattr->attr.mls.lvl;
 	crc = ~crc_ccitt(0xffff, calipso, len);
 	calipso[8] = crc & 0xff;
 	calipso[9] = (crc >> 8) & 0xff;

Re: [PATCH 4/5] net/ipv6: use semicolons rather than commas to separate statements

[Paul Moore]

On Sun, Oct 11, 2020 at 7:18 AM Julia Lawall <Julia.Lawall@inria.fr> wrote:
>
> Replace commas with semicolons.  Commas introduce unnecessary
> variability in the code structure and are hard to see.  What is done
> is essentially described by the following Coccinelle semantic patch
> (http://coccinelle.lip6.fr/):
>
> // <smpl>
> @@ expression e1,e2; @@
> e1
> -,
> +;
> e2
> ... when any
> // </smpl>
>
> Signed-off-by: Julia Lawall <Julia.Lawall@inria.fr>
>
> ---
>  net/ipv6/calipso.c |    2 +-
>  1 file changed, 1 insertion(+), 1 deletion(-)

Thanks Julia.

Acked-by: Paul Moore <paul@paul-moore.com>

> diff --git a/net/ipv6/calipso.c b/net/ipv6/calipso.c
> index 8d3f66c310db..78f766019b7e 100644
> --- a/net/ipv6/calipso.c
> +++ b/net/ipv6/calipso.c
> @@ -761,7 +761,7 @@ static int calipso_genopt(unsigned char *buf, u32 start, u32 buf_len,
>         calipso[1] = len - 2;
>         *(__be32 *)(calipso + 2) = htonl(doi_def->doi);
>         calipso[6] = (len - CALIPSO_HDR_LEN) / 4;
> -       calipso[7] = secattr->attr.mls.lvl,
> +       calipso[7] = secattr->attr.mls.lvl;
>         crc = ~crc_ccitt(0xffff, calipso, len);
>         calipso[8] = crc & 0xff;
>         calipso[9] = (crc >> 8) & 0xff;

-- 
paul moore
www.paul-moore.com

Re: [PATCH 0/5] net: use semicolons rather than commas to separate statements

[Jakub Kicinski]

On Sun, 11 Oct 2020 12:34:53 +0200 Julia Lawall wrote:
> These patches replace commas by semicolons.  Commas introduce
> unnecessary variability in the code structure and are hard to see.
> This was done using the Coccinelle semantic patch
> (http://coccinelle.lip6.fr/) shown below.

Applied 3-5 to net-next, thanks!