2 files changed, 43 insertions, 15 deletions

diff --git a/unit_trace/trace_reader.py b/unit_trace/trace_reader.py
index a4c3c05..db36c13 100644
--- a/unit_trace/trace_reader.py
+++ b/unit_trace/trace_reader.py
@@ -34,7 +34,7 @@ import sys
 ###############################################################################
 
 # Generator function returning an iterable over records in a trace file.
-def trace_reader(files):
+def trace_reader(files, buffsize):
 
     # Yield a record containing the input files
     # This is used by progress.py to calculate progress
@@ -66,17 +66,15 @@ def trace_reader(files):
             # Forget that file iter
             file_iters.pop()
 
-    # We keep 200 records in each buffer and then keep the buffer sorted
-    # This is because records may have been recorded slightly out of order
-    # This cannot guarantee records are produced in order, but it makes it
-    # overwhelmingly probably.
-    # The 'try' and 'except' catches the case where there are less than 200
-    # records in a file (throwing a StopIteration) which otherwise would
-    # propogate up and cause the trace_reader generator itself to throw a
-    # StopIteration.
+    # We keep some number of records (given as buffsize) in each buffer and
+    # then keep the buffer sorted.  This is because records may have been
+    # recorded slightly out of order.  The 'try' and 'except' catches the case
+    # where there are less than buffsize records in a file (throwing a
+    # StopIteration) which otherwise would propogate up and cause the
+    # trace_reader generator itself to throw a StopIteration.
     for x in range(0,len(file_iter_buff)):
         try:
-            for y in range(0,200):
+            for y in range(0,buffsize):
                 file_iter_buff[x].append(file_iters[x].next())
         except StopIteration:
             pass
@@ -119,16 +117,20 @@ def trace_reader(files):
                 del file_iter_buff[buff_to_refill]
                 del file_iters[buff_to_refill]
 
+        # Give the record an id number
+        id += 1
+        earliest.id = id
+
         # Check for monotonically increasing time
         if last_time is not None and earliest.when < last_time:
-            exit("FATAL ERROR: trace_reader.py: out-of-order record produced")
+            record = Obj()
+            record.record_type = "meta"
+            record.type_name = "out_of_order_warning"
+            record.id = earliest.id
+            yield record
         else:
             last_time = earliest.when
 
-        # Give the record an id number
-        id += 1
-        earliest.id = id
-
         # Yield the record
         yield earliest
 
diff --git a/unit_trace/warning_printer.py b/unit_trace/warning_printer.py
new file mode 100644
index 0000000..0f726ff
--- /dev/null
+++ b/unit_trace/warning_printer.py
@@ -0,0 +1,26 @@
+###############################################################################
+# Description
+###############################################################################
+
+# Display any warnings
+
+###############################################################################
+# Imports
+###############################################################################
+
+import sys
+
+###############################################################################
+# Public functions
+###############################################################################
+
+def warning_printer(stream):
+    out_of_order_ids = []
+    for record in stream:
+        if (record.record_type == "meta" and
+            record.type_name == "out_of_order_warning"):
+            out_of_order_ids.append(record.id)
+    if len(out_of_order_ids) > 0:
+        sys.stderr.write(
+            "WARNING: The following {0} records were out of order:\n{1}\n".format(
+            len(out_of_order_ids), out_of_order_ids))