[bugzilla-gnome-org-extensions] Make TraceParser better at determining which thread/threads are "interesting" when there is no <sign

[Krzesimir Nowak <krnowak src gnome org>]

commit b8368e1ecb6f2236409411b81a7ef4d4fdfc36e8
Author: Max Kanat-Alexander <mkanat everythingsolved com>
Date:   Sat Aug 8 21:47:28 2009 -0500

    Make TraceParser better at determining which thread/threads are "interesting"
    when there is no <signal handler called> in the thread.

 lib/TraceParser/Trace.pm                   |   53 ++++++++++++++++++++++++++--
 template/en/default/pages/trace.html.tmpl  |    3 +-
 template/en/default/trace/format.html.tmpl |    7 ++--
 3 files changed, 55 insertions(+), 8 deletions(-)
---
diff --git a/lib/TraceParser/Trace.pm b/lib/TraceParser/Trace.pm
index ec81315..39e87a7 100644
--- a/lib/TraceParser/Trace.pm
+++ b/lib/TraceParser/Trace.pm
@@ -78,6 +78,20 @@ use constant IGNORE_FUNCTIONS => qw(
    ??
 );
 
+# If a trace lacks <signal handler called>, we determine the
+# "interesting thread" by looking for a thread that has
+# functions that match this regex.
+use constant POSSIBLE_CRASH_FUNCTION => qr/signal|segv|sighandler/i;
+
+# Or if that fails, by a thread whose last function *doesn't* match
+# this regex.
+use constant WAIT_FUNCTION => qr/wait|sleep|poll/i;
+
+# However, some wait functions are interesting--for example,
+# if we're waiting on a lock, that's interesting during
+# deadlock traces.
+use constant INTERESTING_WAIT_FUNCTION => qr/lock/i;
+
 ################
 # Constructors #
 ################
@@ -238,10 +252,42 @@ sub comment_is_private {
     return $self->{comment_is_private};
 }
 
-sub crash_thread {
+sub interesting_threads {
     my ($invocant, $st) = @_;
     $st ||= $invocant->stack;
-    return $st->thread_with_crash || $st->threads->[0];
+    # If there's only one thread, return that.
+    if (scalar(@{ $st->threads }) == 1) {
+        return [$st->threads->[0]];
+    }
+
+    # If there's a thread with an explicit signal handler,
+    # then that's the one we want.
+    my $thread = $st->thread_with_crash;
+    return [$thread] if $thread;
+
+    # Search for threads that have a function with
+    # "signal" or "segv" in the name.
+    my @threads;
+    foreach my $t (@{ $st->threads }) {
+        if (grep { $_->function =~ POSSIBLE_CRASH_FUNCTION } @{ $t->frames }) {
+            push(@threads, $t);
+        }
+    }
+    return \ threads if @threads;
+
+    # If we still don't have a thread, return every first thread whose
+    # last function isn't some form of wait or one of the ignored
+    # functions.
+    foreach my $t (@{ $st->threads }) {
+        my $function = $t->frames->[0]->function;
+        if (($function !~ WAIT_FUNCTION
+             or $function =~ INTERESTING_WAIT_FUNCTION)
+            and !grep { $_ eq $function } IGNORE_FUNCTIONS)
+        {
+            push(@threads, $t);
+        }
+    }
+    return \ threads;
 }
 
 sub identical_traces {
@@ -288,7 +334,8 @@ sub _important_stack_frames {
     my ($invocant, $st) = @_;
     $st ||= $invocant->stack;
 
-    my $crash_thread = $invocant->crash_thread($st);
+    my $int_threads = $invocant->interesting_threads($st);
+    my $crash_thread = @$int_threads ? $int_threads->[0] : $st->threads->[0];
     my $frames = $crash_thread->frames;
 
     my $crash_position;
diff --git a/template/en/default/pages/trace.html.tmpl b/template/en/default/pages/trace.html.tmpl
index 35a16bc..a6f7ece 100644
--- a/template/en/default/pages/trace.html.tmpl
+++ b/template/en/default/pages/trace.html.tmpl
@@ -57,7 +57,8 @@
 [% END %]
 
 <h2>Trace [% trace.id FILTER html %] 
-  (Quality: [% trace.quality FILTER html %])</h2>
+  (Quality: [% trace.quality FILTER html %]) on 
+  [%+ "$terms.Bug $trace.bug.id" FILTER bug_link(trace.bug) %]</h2>
 
 <table border="0" cellpadding="0" cellspacing="0"><tr><td><div class="trace">
 <pre>[% trace.text FILTER html %]
diff --git a/template/en/default/trace/format.html.tmpl b/template/en/default/trace/format.html.tmpl
index 1c2472b..57444c7 100644
--- a/template/en/default/trace/format.html.tmpl
+++ b/template/en/default/trace/format.html.tmpl
@@ -55,11 +55,10 @@
         [%- thread.description FILTER html %]</span>
     [% END %]
   [% ELSE %]
-    [% SET st = trace.stack %]
-    [% IF st.thread_with_crash %]
-      [% threads = [st.thread_with_crash] %]
+    [% IF trace.interesting_threads %]
+      [% threads = trace.interesting_threads %]
     [% ELSE %]
-      [% threads = st.threads %]
+      [% threads = trace.stack.threads %]
     [% END %]
     
     [% FOREACH thread = threads %]