crash_test to put DB under TEST_TMPDIR

Summary: Currently crash_test only puts data under /tmp. It is less flexible if we want to cover different file systems or media. Make crash_test to appreciate TEST_TMPDIR so that users can run it against another file system.

Test Plan: Run blackbox_crash_test and whitebox_crash_test with or without TEST_TMPDIR set and make sure DBs are put in the right place

Reviewers: kradhakrishnan, yhchiang, rven, IslamAbdelRahman

Reviewed By: IslamAbdelRahman

Subscribers: leveldb, dhruba

Differential Revision: https://reviews.facebook.net/D43509

tools/db_crashtest.py

@@ -67,7 +67,11 @@ def main(argv):
           + str(ops_per_thread) + "\nwrite_buffer_size="
           + str(write_buf_size) + "\n")
 
+    test_tmpdir = os.environ.get("TEST_TMPDIR")
+    if test_tmpdir is None or test_tmpdir == "":
         dbname = tempfile.mkdtemp(prefix='rocksdb_crashtest_')
+    else:
+        dbname = test_tmpdir + "/rocksdb_crashtest"
 
     while time.time() < exit_time:
         run_had_errors = False

tools/db_crashtest2.py

@@ -70,7 +70,12 @@ def main(argv):
     total_check_mode = 4
     check_mode = 0
 
-    dbname = tempfile.mkdtemp(prefix='rocksdb_crashtest_')
+    test_tmpdir = os.environ.get("TEST_TMPDIR")
+    if test_tmpdir is None or test_tmpdir == "":
+        dbname = tempfile.mkdtemp(prefix='rocksdb_crashtest2_')
+    else:
+        dbname = test_tmpdir + "/rocksdb_crashtest2"
+
     while time.time() < exit_time:
         killoption = ""
         if check_mode == 0: