lkml.org 
[lkml]   [2008]   [Dec]   [21]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
Patch in this message
/
Date
From
Subject[PATCH 6/13] drivers/net: Remove redundant test
From: Julia Lawall <julia@diku.dk>

In each case, ap is checked not to be NULL a few lines before.

A simplified version of the semantic patch that makes this change is as
follows: (http://www.emn.fr/x-info/coccinelle/)

// <smpl>
@r exists@
local idexpression x;
expression E;
position p1,p2;
@@

if (x@p1 == NULL || ...) { ... when forall
return ...; }
... when != \(x=E\|x--\|x++\|--x\|++x\|x-=E\|x+=E\|x|=E\|x&=E\|&x\)
(
x@p2 == NULL
|
x@p2 != NULL
)

// another path to the test that is not through p1?
@s exists@
local idexpression r.x;
position r.p1,r.p2;
@@

... when != x@p1
(
x@p2 == NULL
|
x@p2 != NULL
)

@fix depends on !s@
position r.p1,r.p2;
expression x,E;
statement S1,S2;
@@

(
- if ((x@p2 != NULL) || ...)
S1
|
- if ((x@p2 == NULL) && ...) S1
|
- BUG_ON(x@p2 == NULL);
)
// </smpl>

Signed-off-by: Julia Lawall <julia@diku.dk>

---
drivers/net/ppp_async.c | 6 ------
drivers/net/ppp_synctty.c | 6 ------
2 files changed, 12 deletions(-)

diff --git a/drivers/net/ppp_async.c b/drivers/net/ppp_async.c
index 451bdb5..6567fab 100644
--- a/drivers/net/ppp_async.c
+++ b/drivers/net/ppp_async.c
@@ -293,9 +293,6 @@ ppp_asynctty_ioctl(struct tty_struct *tty, struct file *file,
err = -EFAULT;
switch (cmd) {
case PPPIOCGCHAN:
- err = -ENXIO;
- if (!ap)
- break;
err = -EFAULT;
if (put_user(ppp_channel_index(&ap->chan), p))
break;
@@ -303,9 +300,6 @@ ppp_asynctty_ioctl(struct tty_struct *tty, struct file *file,
break;

case PPPIOCGUNIT:
- err = -ENXIO;
- if (!ap)
- break;
err = -EFAULT;
if (put_user(ppp_unit_number(&ap->chan), p))
break;
diff --git a/drivers/net/ppp_synctty.c b/drivers/net/ppp_synctty.c
index 801d8f9..1e892b7 100644
--- a/drivers/net/ppp_synctty.c
+++ b/drivers/net/ppp_synctty.c
@@ -333,9 +333,6 @@ ppp_synctty_ioctl(struct tty_struct *tty, struct file *file,
err = -EFAULT;
switch (cmd) {
case PPPIOCGCHAN:
- err = -ENXIO;
- if (!ap)
- break;
err = -EFAULT;
if (put_user(ppp_channel_index(&ap->chan), p))
break;
@@ -343,9 +340,6 @@ ppp_synctty_ioctl(struct tty_struct *tty, struct file *file,
break;

case PPPIOCGUNIT:
- err = -ENXIO;
- if (!ap)
- break;
err = -EFAULT;
if (put_user(ppp_unit_number(&ap->chan), p))
break;

\
 
 \ /
  Last update: 2008-12-21 16:41    [W:0.049 / U:0.572 seconds]
©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site