From 2a41d7b0ffc6156c3cda9e2c7aee5dc25a1c6b8c Mon Sep 17 00:00:00 2001
From: Jules Villard <jul@fb.com>
Date: Tue, 29 Mar 2016 11:47:53 -0700
Subject: [PATCH] always create .start if it doesn't exist

Summary:public
`rm -rf infer-out && infer --reactive --continue -a capture -- clang -c hello.c` used to crash.

closes #315

Differential Revision: D3109673

fb-gh-sync-id: 661bd07
fbshipit-source-id: 661bd07
---
 infer/lib/python/infer               | 4 ++--
 infer/lib/python/inferlib/analyze.py | 9 +++++----
 2 files changed, 7 insertions(+), 6 deletions(-)

diff --git a/infer/lib/python/infer b/infer/lib/python/infer
index 530c27b07..41435c49b 100755
--- a/infer/lib/python/infer
+++ b/infer/lib/python/infer
@@ -126,8 +126,8 @@ def main():
 
     if imported_module:
         analyze.create_results_dir(args.infer_out)
-        if not args.continue_capture:
-            analyze.reset_start_file(args.infer_out)
+        analyze.reset_start_file(args.infer_out,
+                                 touch_if_present=not args.continue_capture)
 
         utils.configure_logging(args)
         logging.info('Running command %s', ' '.join(sys.argv))
diff --git a/infer/lib/python/inferlib/analyze.py b/infer/lib/python/inferlib/analyze.py
index 909ff079c..bd2f177c2 100644
--- a/infer/lib/python/inferlib/analyze.py
+++ b/infer/lib/python/inferlib/analyze.py
@@ -175,10 +175,11 @@ def create_results_dir(results_dir):
     utils.mkdir_if_not_exists(os.path.join(results_dir, 'sources'))
 
 
-def reset_start_file(results_dir):
-    # create new empty file - this will update modified timestamp
-    open(os.path.join(results_dir, '.start'), 'w').close()
-
+def reset_start_file(results_dir, touch_if_present=False):
+    start_path = os.path.join(results_dir, '.start')
+    if (not os.path.exists(start_path)) or touch_if_present:
+        # create new empty file - this will update modified timestamp
+        open(start_path, 'w').close()
 
 def clean(infer_out):
     directories = [