Make TARGETS file portable

Summary:
Instead of hard coding the path of the internal repo.
Make TARGETS file work anywhere in fbcode
Closes https://github.com/facebook/rocksdb/pull/2586

Differential Revision: D5428122

Pulled By: IslamAbdelRahman

fbshipit-source-id: 21adec82bfbff14ea93532bee789b5f5bbee5b01

TARGETS

@@ -1,4 +1,8 @@
-REPO_PATH = "internal_repo_rocksdb/repo/"
+
+import os
+
+TARGETS_PATH = os.path.dirname(__file__)
+REPO_PATH = TARGETS_PATH[(TARGETS_PATH.find('fbcode/') + len('fbcode/')):] + "/"
 BUCK_BINS = "buck-out/gen/" + REPO_PATH
 TEST_RUNNER = REPO_PATH + "buckifier/rocks_test_runner.sh"
 rocksdb_compiler_flags = [

buckifier/targets_cfg.py

@@ -2,7 +2,11 @@ from __future__ import absolute_import
 from __future__ import division
 from __future__ import print_function
 from __future__ import unicode_literals
-rocksdb_target_header = """REPO_PATH = "internal_repo_rocksdb/repo/"
+rocksdb_target_header = """
+import os
+
+TARGETS_PATH = os.path.dirname(__file__)
+REPO_PATH = TARGETS_PATH[(TARGETS_PATH.find('fbcode/') + len('fbcode/')):] + "/"
 BUCK_BINS = "buck-out/gen/" + REPO_PATH
 TEST_RUNNER = REPO_PATH + "buckifier/rocks_test_runner.sh"
 rocksdb_compiler_flags = [