build.py: Add a log to capture task execution order

The new log.task_order contains an ordered list of the tasks as they
were executed in any given recipe.  The format of the lines is
<task> <pid>: <log file>

Signed-off-by: Mark Hatle <mark.hatle@windriver.com>
Signed-off-by: Richard Purdie <richard.purdie@linuxfoundation.org>

1 files changed, 15 insertions, 1 deletions

diff --git a/lib/bb/build.py b/lib/bb/build.py
index 95f1dcfcb..4f06b1594 100644
--- a/lib/bb/build.py
+++ b/lib/bb/build.py
@@ -290,8 +290,22 @@ def _exec_task(fn, task, d, quieterr):
         bb.fatal("T variable not set, unable to build")
 
     bb.utils.mkdirhier(tempdir)
-    loglink = os.path.join(tempdir, 'log.{0}'.format(task))
+
+    # Determine the logfile to generate
     logbase = 'log.{0}.{1}'.format(task, os.getpid())
+
+    # Document the order of the tasks...
+    logorder = os.path.join(tempdir, 'log.task_order')
+    try:
+        logorderfile = file(logorder, 'a')
+    except OSError:
+        logger.exception("Opening log file '%s'", logorder)
+        pass
+    logorderfile.write('{0} ({1}): {2}\n'.format(task, os.getpid(), logbase))
+    logorderfile.close()
+
+    # Setup the courtesy link to the logfn
+    loglink = os.path.join(tempdir, 'log.{0}'.format(task))
     logfn = os.path.join(tempdir, logbase)
     if loglink:
         bb.utils.remove(loglink)