[Patch] kbuild: fix headers_check.pl

[Patch] kbuild: fix headers_check.pl

[Amerigo Wang]

'extern' checking information is not clear, refine it.
Plus, fix a comment.

Signed-off-by: WANG Cong <amwang@redhat.com>
Cc: Sam Ravnborg <sam@ravnborg.org>

----
diff --git a/scripts/headers_check.pl b/scripts/headers_check.pl
index 56f90a4..3923888 100644
--- a/scripts/headers_check.pl
+++ b/scripts/headers_check.pl
@@ -2,7 +2,7 @@
 #
 # headers_check.pl execute a number of trivial consistency checks
 #
-# Usage: headers_check.pl dir [files...]
+# Usage: headers_check.pl dir arch [files...]
 # dir:   dir to look for included files
 # arch:  architecture
 # files: list of files to check
@@ -37,7 +37,7 @@ foreach my $file (@files) {
 		&check_include();
 		&check_asm_types();
 		&check_sizetypes();
-		&check_prototypes();
+		&check_declarations();
 		# Dropped for now. Too much noise &check_config();
 	}
 	close FH;
@@ -61,10 +61,14 @@ sub check_include
 	}
 }
 
-sub check_prototypes
+sub check_declarations
 {
-	if ($line =~ m/^\s*extern\b/) {
-		printf STDERR "$filename:$lineno: extern's make no sense in userspace\n";
+	if ($line =~m/^\s*extern\b/) {
+		if ($line =~ m/^\s*extern\b.*\(.*\)/) {
+			printf STDERR "$filename:$lineno: extern's make no sense in userspace\n";
+		} else {
+			printf STDERR "$filename:$lineno: exporting global variable to userspace is suspicious\n";
+		}
 	}
 }
 

[Patch] kbuild: clean up scripts/headers.sh

[Amerigo Wang]

'drop' variable is unused.

'ppc' and 'sparc64' directories don't exist in arch/,
and I think their headers can be well exported now, so
just remove them.

Signed-off-by: WANG Cong <amwang@redhat.com>
Cc: Sam Ravnborg <sam@ravnborg.org>

------
diff --git a/scripts/headers.sh b/scripts/headers.sh
index d33426f..0308ecc 100755
--- a/scripts/headers.sh
+++ b/scripts/headers.sh
@@ -15,19 +15,12 @@ do_command()
 	fi
 }
 
-# Do not try this architecture
-drop="generic um ppc sparc64 cris"
-
 archs=$(ls ${srctree}/arch)
 
 for arch in ${archs}; do
 	case ${arch} in
 	um)        # no userspace export
 		;;
-	ppc)       # headers exported by powerpc
-		;;
-	sparc64)   # headers exported by sparc
-		;;
 	cris)      # headers export are known broken
 		;;
 	*)

Re: [Patch] kbuild: fix headers_check.pl

[Arnd Bergmann]

On Friday 05 June 2009, Amerigo Wang wrote:
> -sub check_prototypes
> +sub check_declarations
>  {
> -       if ($line =~ m/^\s*extern\b/) {
> -               printf STDERR "$filename:$lineno: extern's make no sense in userspace\n";
> +       if ($line =~m/^\s*extern\b/) {
> +               if ($line =~ m/^\s*extern\b.*\(.*\)/) {
> +                       printf STDERR "$filename:$lineno: extern's make no sense in userspace\n";
> +               } else {
> +                       printf STDERR "$filename:$lineno: exporting global variable to userspace is suspicious\n";
> +               }
>         }
>  }

I don't think we really need that distinction here, the old
text applies to both. But please find a way to get rid of
the "extern's".

http://angryflower.com/bobsqu.gif

	Arnd <><

Re: [Patch] kbuild: fix headers_check.pl

[Amerigo Wang]

Arnd Bergmann wrote:
> On Friday 05 June 2009, Amerigo Wang wrote:
>   
>> -sub check_prototypes
>> +sub check_declarations
>>  {
>> -       if ($line =~ m/^\s*extern\b/) {
>> -               printf STDERR "$filename:$lineno: extern's make no sense in userspace\n";
>> +       if ($line =~m/^\s*extern\b/) {
>> +               if ($line =~ m/^\s*extern\b.*\(.*\)/) {
>> +                       printf STDERR "$filename:$lineno: extern's make no sense in userspace\n";
>> +               } else {
>> +                       printf STDERR "$filename:$lineno: exporting global variable to userspace is suspicious\n";
>> +               }
>>         }
>>  }
>>     
>
> I don't think we really need that distinction here, the old
> text applies to both.
Even for function declarations?
> But please find a way to get rid of
> the "extern's".
>   
Here, that one has already been removed by other patch ...

Re: [Patch] kbuild: fix headers_check.pl

[Artem Bityutskiy]

Arnd Bergmann wrote:
> On Friday 05 June 2009, Amerigo Wang wrote:
>> -sub check_prototypes
>> +sub check_declarations
>>  {
>> -       if ($line =~ m/^\s*extern\b/) {
>> -               printf STDERR "$filename:$lineno: extern's make no sense in userspace\n";
>> +       if ($line =~m/^\s*extern\b/) {
>> +               if ($line =~ m/^\s*extern\b.*\(.*\)/) {
>> +                       printf STDERR "$filename:$lineno: extern's make no sense in userspace\n";
>> +               } else {
>> +                       printf STDERR "$filename:$lineno: exporting global variable to userspace is suspicious\n";
>> +               }
>>         }
>>  }
> 
> I don't think we really need that distinction here, the old
> text applies to both. But please find a way to get rid of
> the "extern's".
> 
> http://angryflower.com/bobsqu.gif

Hehe, made me smile :-)

Re: [Patch] kbuild: fix headers_check.pl

[Arnd Bergmann]

On Friday 05 June 2009, Amerigo Wang wrote:
> 
> >
> > I don't think we really need that distinction here, the old
> > text applies to both.
>
> Even for function declarations?

Yes. Any use of 'extern' in a kernel header file by definition
refers to a symbol that is defined in the kernel and therefore
not accessibly in user space. It is the same problem for
variables and functions, with the complication that leaving
out the 'extern' statement on a function declaration will
hide it from this check, while leaving it out on a variable
declaration turns it into a definition.

	Arnd <><

Re: [Patch] kbuild: fix headers_check.pl

[Sam Ravnborg]

On Thu, Jun 04, 2009 at 10:12:01PM -0400, Amerigo Wang wrote:
> 
> 'extern' checking information is not clear, refine it.
> Plus, fix a comment.

Applied,
	Sam

Re: [Patch] kbuild: clean up scripts/headers.sh

[Sam Ravnborg]

On Thu, Jun 04, 2009 at 10:12:09PM -0400, Amerigo Wang wrote:
> 
> 'drop' variable is unused.
> 
> 'ppc' and 'sparc64' directories don't exist in arch/,
> and I think their headers can be well exported now, so
> just remove them.

Applied,
	Sam