diff mbox series

[iproute2] lib: bpf_glue: remove useless assignment

Message ID 25ea92f064e11ba30ae696b176df9d6b0aaaa66a.1628352013.git.aclaudi@redhat.com (mailing list archive)
State Accepted
Delegated to: Stephen Hemminger
Headers show
Series [iproute2] lib: bpf_glue: remove useless assignment | expand

Checks

Context Check Description
netdev/tree_selection success Not a local patch

Commit Message

Andrea Claudi Aug. 7, 2021, 4:58 p.m. UTC
The value of s used inside the cycle is the result of strstr(), so this
assignment is useless.

Signed-off-by: Andrea Claudi <aclaudi@redhat.com>
---
 lib/bpf_glue.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

Comments

Stephen Hemminger Aug. 11, 2021, 3 a.m. UTC | #1
On Sat,  7 Aug 2021 18:58:02 +0200
Andrea Claudi <aclaudi@redhat.com> wrote:

> -	while ((s = fgets(buf, sizeof(buf), fp)) != NULL) {
> +	while (fgets(buf, sizeof(buf), fp) != NULL) {
>  		if ((s = strstr(buf, "libbpf.so.")) != NULL) {

Ok. but it would be good to get rid of the unnecessary assignment in conditional as well.
Andrea Claudi Aug. 11, 2021, 9:12 a.m. UTC | #2
On Tue, Aug 10, 2021 at 08:00:48PM -0700, Stephen Hemminger wrote:
> On Sat,  7 Aug 2021 18:58:02 +0200
> Andrea Claudi <aclaudi@redhat.com> wrote:
> 
> > -	while ((s = fgets(buf, sizeof(buf), fp)) != NULL) {
> > +	while (fgets(buf, sizeof(buf), fp) != NULL) {
> >  		if ((s = strstr(buf, "libbpf.so.")) != NULL) {
> 
> Ok. but it would be good to get rid of the unnecessary assignment in conditional as well.
> 
Hi Stephen,
That's not unnecessary, s is used as the second parameter in the following strncpy().
Stephen Hemminger Aug. 11, 2021, 4:08 p.m. UTC | #3
On Wed, 11 Aug 2021 11:12:43 +0200
Andrea Claudi <aclaudi@redhat.com> wrote:

> On Tue, Aug 10, 2021 at 08:00:48PM -0700, Stephen Hemminger wrote:
> > On Sat,  7 Aug 2021 18:58:02 +0200
> > Andrea Claudi <aclaudi@redhat.com> wrote:
> >   
> > > -	while ((s = fgets(buf, sizeof(buf), fp)) != NULL) {
> > > +	while (fgets(buf, sizeof(buf), fp) != NULL) {
> > >  		if ((s = strstr(buf, "libbpf.so.")) != NULL) {  
> > 
> > Ok. but it would be good to get rid of the unnecessary assignment in conditional as well.
> >   
> Hi Stephen,
> That's not unnecessary, s is used as the second parameter in the following strncpy().
> 


It is bad style in C to do assignment in a conditional.
It causes errors, and is not anymore efficient.
Andrea Claudi Aug. 12, 2021, 9:01 a.m. UTC | #4
On Wed, Aug 11, 2021 at 09:08:15AM -0700, Stephen Hemminger wrote:
> It is bad style in C to do assignment in a conditional.
> It causes errors, and is not anymore efficient.
> 
I agree with you.

There is a large number of similar assignments in other parts of the
code; I can work on a treewide patch to address them all, if you think
it's a good idea.
Stephen Hemminger Aug. 12, 2021, 4:26 p.m. UTC | #5
On Thu, 12 Aug 2021 11:01:42 +0200
Andrea Claudi <aclaudi@redhat.com> wrote:

> On Wed, Aug 11, 2021 at 09:08:15AM -0700, Stephen Hemminger wrote:
> > It is bad style in C to do assignment in a conditional.
> > It causes errors, and is not anymore efficient.
> >   
> I agree with you.
> 
> There is a large number of similar assignments in other parts of the
> code; I can work on a treewide patch to address them all, if you think
> it's a good idea.
> 

I am looking into this, checkpatch seems to find them
diff mbox series

Patch

diff --git a/lib/bpf_glue.c b/lib/bpf_glue.c
index eaa9504f..70d00184 100644
--- a/lib/bpf_glue.c
+++ b/lib/bpf_glue.c
@@ -63,7 +63,7 @@  const char *get_libbpf_version(void)
 	if (fp == NULL)
 		goto out;
 
-	while ((s = fgets(buf, sizeof(buf), fp)) != NULL) {
+	while (fgets(buf, sizeof(buf), fp) != NULL) {
 		if ((s = strstr(buf, "libbpf.so.")) != NULL) {
 			strncpy(_libbpf_version, s+10, sizeof(_libbpf_version)-1);
 			strtok(_libbpf_version, "\n");