[OE-core] [PATCH 2/6] classes/buildhistory: write out task signatures on every build

[Paul Eggleton]

If we want to determine what changed since the last build, one angle
from which to look at it is to check the signatures. However, if we
don't actually have the signatures from the last build we don't have
anywhere to start. Save the signatures on each build in order to give us
the starting point.

NOTE: you need to set your BUILDHISTORY_FEATURES value to include
"task" to enable collection of these signatures as it is is disabled by
default.

Signed-off-by: Paul Eggleton <paul.eggleton at linux.intel.com>
---
 meta/classes/buildhistory.bbclass | 12 ++++++++++++
 meta/lib/oe/sstatesig.py          | 10 ++++++++++
 2 files changed, 22 insertions(+)

diff --git a/meta/classes/buildhistory.bbclass b/meta/classes/buildhistory.bbclass
index 109b375..0cafad5 100644
--- a/meta/classes/buildhistory.bbclass
+++ b/meta/classes/buildhistory.bbclass
@@ -596,6 +596,17 @@ POPULATE_SDK_POST_HOST_COMMAND[vardepvalueexclude] .= "| buildhistory_list_insta
 SDK_POSTPROCESS_COMMAND_append = " buildhistory_get_sdkinfo ; buildhistory_get_extra_sdkinfo; "
 SDK_POSTPROCESS_COMMAND[vardepvalueexclude] .= "| buildhistory_get_sdkinfo ; buildhistory_get_extra_sdkinfo; "
 
+python buildhistory_write_sigs() {
+    if not "task" in (d.getVar('BUILDHISTORY_FEATURES') or "").split():
+        return
+
+    # Create sigs file
+    if hasattr(bb.parse.siggen, 'dump_siglist'):
+        taskoutdir = os.path.join(d.getVar('BUILDHISTORY_DIR'), 'task')
+        bb.utils.mkdirhier(taskoutdir)
+        bb.parse.siggen.dump_siglist(os.path.join(taskoutdir, 'tasksigs.txt'))
+}
+
 def buildhistory_get_build_id(d):
     if d.getVar('BB_WORKERCONTEXT') != '1':
         return ""
@@ -761,6 +772,7 @@ python buildhistory_eventhandler() {
                 shutil.rmtree(olddir)
             if e.data.getVar("BUILDHISTORY_COMMIT") == "1":
                 bb.note("Writing buildhistory")
+                bb.build.exec_func("buildhistory_write_sigs", d)
                 localdata = bb.data.createCopy(e.data)
                 localdata.setVar('BUILDHISTORY_BUILD_FAILURES', str(e._failures))
                 interrupted = getattr(e, '_interrupted', 0)
diff --git a/meta/lib/oe/sstatesig.py b/meta/lib/oe/sstatesig.py
index 13fd3bd..56b33ba 100644
--- a/meta/lib/oe/sstatesig.py
+++ b/meta/lib/oe/sstatesig.py
@@ -211,6 +211,16 @@ class SignatureGeneratorOEBasicHash(bb.siggen.SignatureGeneratorBasicHash):
                 f.write('    "\n')
             f.write('SIGGEN_LOCKEDSIGS_TYPES_%s = "%s"' % (self.machine, " ".join(l)))
 
+    def dump_siglist(self, sigfile):
+        with open(sigfile, "w") as f:
+            tasks = []
+            for taskitem in self.taskhash:
+                (fn, task) = taskitem.rsplit(".", 1)
+                pn = self.lockedpnmap[fn]
+                tasks.append((pn, task, self.taskhash[taskitem]))
+            for (pn, task, taskhash) in sorted(tasks):
+                f.write('%s.%s %s\n' % (pn, task, taskhash))
+
     def checkhashes(self, missed, ret, sq_fn, sq_task, sq_hash, sq_hashfn, d):
         warn_msgs = []
         error_msgs = []
-- 
2.9.3