localmodconfig: Process source kconfig files as they are found

A bug was reported that caused localmodconfig to not keep all the
dependencies of ATH9K. This was caused by the kconfig file:

In drivers/net/wireless/ath/Kconfig:

---
if ATH_CARDS

config ATH_DEBUG
        bool "Atheros wireless debugging"
        ---help---
          Say Y, if you want to debug atheros wireless drivers.
          Right now only ath9k makes use of this.

source "drivers/net/wireless/ath/ath5k/Kconfig"
source "drivers/net/wireless/ath/ath9k/Kconfig"
source "drivers/net/wireless/ath/carl9170/Kconfig"
source "drivers/net/wireless/ath/ath6kl/Kconfig"
source "drivers/net/wireless/ath/ar5523/Kconfig"
source "drivers/net/wireless/ath/wil6210/Kconfig"

endif
---

The current way kconfig works, it processes new source files after the
first file is completed. It creates an array of new source config files
and when the one file is finished, it continues with the next file.

Unfortunately, this means that it loses the fact that the source file is
within an "if" statement, and this means that each of these source file's
configs will not have the proper dependencies set.

As ATH9K requires ATH_CARDS set, the localmodconfig did not see that
dependency, and did not enable ATH_CARDS. When the oldconfig was run, it
forced ATH9K to be disabled.

Link: http://lkml.kernel.org/r/alpine.DEB.2.02.1304291022320.9234@oneiric

Cc: [email protected] # 3.8+
Reported-by: Robert P. J. Day <[email protected]>
Tested-by: Robert P. J. Day <[email protected]>
Signed-off-by: Steven Rostedt <[email protected]>

scripts/kconfig/streamline_config.pl

@@ -156,7 +156,6 @@ sub read_kconfig {
 
     my $state = "NONE";
     my $config;
-    my @kconfigs;
 
     my $cont = 0;
     my $line;
@@ -190,7 +189,13 @@ sub read_kconfig {
 
 	# collect any Kconfig sources
 	if (/^source\s*"(.*)"/) {
-	    $kconfigs[$#kconfigs+1] = $1;
+	    my $kconfig = $1;
+	    # prevent reading twice.
+	    if (!defined($read_kconfigs{$kconfig})) {
+		$read_kconfigs{$kconfig} = 1;
+		read_kconfig($kconfig);
+	    }
+	    next;
 	}
 
 	# configs found
@@ -250,14 +255,6 @@ sub read_kconfig {
 	}
     }
     close($kinfile);
-
-    # read in any configs that were found.
-    foreach my $kconfig (@kconfigs) {
-	if (!defined($read_kconfigs{$kconfig})) {
-	    $read_kconfigs{$kconfig} = 1;
-	    read_kconfig($kconfig);
-	}
-    }
 }
 
 if ($kconfig) {