ktest: Add make_warnings_file and process full warnings

Although the patchcheck test checks for warnings in the files that were
changed, this check does not catch warnings that were caused by header
file changes and the warnings appear in C files not touched by the
commit.

Add a new option called WARNINGS_FILE. If this option is set, then the
file it points to is read before bulid, and the file should contain a
list of known warnings. If a warning appears in the build, this file is
checked, and if the warning does not exist in this file, then it fails
the build showing the new warning.

If the WARNINGS_FILE points to a file that does not exist, this will
cause any warning in the build to fail.

A new test is also added called "make_warnings_file". This test will
create do a build and record any warnings it finds into the
WARNINGS_FILE. This test is something that can be run before other tests
to build a warnings file of "known warnings", ie, warnings that were
there before your changes.

Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
diff --git a/tools/testing/ktest/ktest.pl b/tools/testing/ktest/ktest.pl
index 3d19ee4..3fd768e 100755
--- a/tools/testing/ktest/ktest.pl
+++ b/tools/testing/ktest/ktest.pl
@@ -126,6 +126,7 @@
 my $output_minconfig;
 my $minconfig_type;
 my $use_output_minconfig;
+my $warnings_file;
 my $ignore_config;
 my $ignore_errors;
 my $addconfig;
@@ -193,6 +194,9 @@
 # which would require more options.
 my $buildonly = 1;
 
+# tell build not to worry about warnings, even when WARNINGS_FILE is set
+my $warnings_ok = 0;
+
 # set when creating a new config
 my $newconfig = 0;
 
@@ -235,6 +239,7 @@
     "START_MIN_CONFIG"		=> \$start_minconfig,
     "MIN_CONFIG_TYPE"		=> \$minconfig_type,
     "USE_OUTPUT_MIN_CONFIG"	=> \$use_output_minconfig,
+    "WARNINGS_FILE"		=> \$warnings_file,
     "IGNORE_CONFIG"		=> \$ignore_config,
     "TEST"			=> \$run_test,
     "ADD_CONFIG"		=> \$addconfig,
@@ -1924,7 +1929,60 @@
     return monitor;
 }
 
+my $check_build_re = ".*:.*(warning|error|Error):.*";
+my $utf8_quote = "\\x{e2}\\x{80}(\\x{98}|\\x{99})";
+
+# Read buildlog and check against warnings file for any
+# new warnings.
+#
+# Returns 1 if OK
+#         0 otherwise
 sub check_buildlog {
+    return 1 if (!defined $warnings_file);
+
+    my %warnings_list;
+
+    # Failed builds should not reboot the target
+    my $save_no_reboot = $no_reboot;
+    $no_reboot = 1;
+
+    if (-f $warnings_file) {
+	open(IN, $warnings_file) or
+	    dodie "Error opening $warnings_file";
+
+	while (<IN>) {
+	    if (/$check_build_re/) {
+		chomp;
+		$warnings_list{$_} = 1;
+	    }
+	}
+	close(IN);
+    }
+
+    # If warnings file didn't exist, and WARNINGS_FILE exist,
+    # then we fail on any warning!
+
+    open(IN, $buildlog) or dodie "Can't open $buildlog";
+    while (<IN>) {
+	if (/$check_build_re/) {
+
+	    # Some compilers use UTF-8 extended for quotes
+	    # for distcc heterogeneous systems, this causes issues
+	    s/$utf8_quote/'/g;
+
+	    chomp;
+	    if (!defined $warnings_list{$_}) {
+		fail "New warning found (not in $warnings_file)\n$_\n";
+		$no_reboot = $save_no_reboot;
+		return 0;
+	    }
+	}
+    }
+    $no_reboot = $save_no_reboot;
+    close(IN);
+}
+
+sub check_patch_buildlog {
     my ($patch) = @_;
 
     my @files = `git show $patch | diffstat -l`;
@@ -3080,11 +3138,13 @@
 	    build "oldconfig" or return 0;
 	}
 
-
-	if (!defined($ignored_warnings{$sha1})) {
-	    check_buildlog $sha1 or return 0;
+	# No need to do per patch checking if warnings file exists
+	if (!defined($warnings_file) && !defined($ignored_warnings{$sha1})) {
+	    check_patch_buildlog $sha1 or return 0;
 	}
 
+	check_buildlog or return 0;
+
 	next if ($type eq "build");
 
 	my $failed = 0;
@@ -3642,6 +3702,39 @@
     return 1;
 }
 
+sub make_warnings_file {
+    my ($i) = @_;
+
+    if (!defined($warnings_file)) {
+	dodie "Must define WARNINGS_FILE for make_warnings_file test";
+    }
+
+    if ($build_type eq "nobuild") {
+	dodie "BUILD_TYPE can not be 'nobuild' for make_warnings_file test";
+    }
+
+    build $build_type or dodie "Failed to build";
+
+    open(OUT, ">$warnings_file") or dodie "Can't create $warnings_file";
+
+    open(IN, $buildlog) or dodie "Can't open $buildlog";
+    while (<IN>) {
+
+	# Some compilers use UTF-8 extended for quotes
+	# for distcc heterogeneous systems, this causes issues
+	s/$utf8_quote/'/g;
+
+	if (/$check_build_re/) {
+	    print OUT;
+	}
+    }
+    close(IN);
+
+    close(OUT);
+
+    success $i;
+}
+
 $#ARGV < 1 or die "ktest.pl version: $VERSION\n   usage: ktest.pl config-file\n";
 
 if ($#ARGV == 0) {
@@ -3843,9 +3936,9 @@
 	$run_type = $bisect_type;
     } elsif ($test_type eq "config_bisect") {
 	$run_type = $config_bisect_type;
-    }
-
-    if ($test_type eq "make_min_config") {
+    } elsif ($test_type eq "make_min_config") {
+	$run_type = "";
+    } elsif ($test_type eq "make_warnings_file") {
 	$run_type = "";
     }
 
@@ -3902,10 +3995,15 @@
     } elsif ($test_type eq "make_min_config") {
 	make_min_config $i;
 	next;
+    } elsif ($test_type eq "make_warnings_file") {
+	$no_reboot = 1;
+	make_warnings_file $i;
+	next;
     }
 
     if ($build_type ne "nobuild") {
 	build $build_type or next;
+	check_buildlog or next;
     }
 
     if ($test_type eq "install") {