commit bd706d79b15a974b2c346df85a78271e21c3fc62
author Manojkiran Eda <manojkiran.eda@gmail.com> Tue Dec 21 05:09:47 2021 +0530
committer Kuiying Wang <wangkuiying.wky@alibaba-inc.com> Thu Feb 10 06:33:48 2022 +0000
tree c669769a9e6a77a778070aab42533fa3e163dfab
parent 987f91a6536e0330799cc5f4e54740c4023b5ef0

Switch to a thread safe single ton

In the current state the single ton pattern used in the
repository is not thread safe.

Switching the pattern to Meyer's single ton over the trusty
leaky single ton.

Ref : https://jinyu.li/notes/meyers-singleton/

Tested By :
1. Patched post-code-manager deamon & was able to get the post
   codes with the GetPostCodesWithTimeStamp method.

Signed-off-by: Manojkiran Eda <manojkiran.eda@gmail.com>
Change-Id: I0ee5c21f15fc93e1d8c5e62a0fed33622a33c894

src/post_code.cpp

diff --git a/src/post_code.cpp b/src/post_code.cpp
index 1fcbe55..b1ffab8 100644
--- a/src/post_code.cpp
+++ b/src/post_code.cpp
@@ -17,16 +17,14 @@
 
 #include "iomanip"
 
-PostCodeDataHolder* PostCodeDataHolder::instance = 0;
-
 void PostCode::deleteAll()
 {
-    auto dir = fs::path(postcodeDataHolderObj->PostCodeListPathPrefix +
-                        std::to_string(postcodeDataHolderObj->node));
+    auto dir = fs::path(postcodeDataHolderObj.PostCodeListPathPrefix +
+                        std::to_string(postcodeDataHolderObj.node));
     std::uintmax_t n = fs::remove_all(dir);
     std::cerr << "clearPostCodes deleted " << n << " files in "
-              << postcodeDataHolderObj->PostCodeListPathPrefix +
-                     std::to_string(postcodeDataHolderObj->node)
+              << postcodeDataHolderObj.PostCodeListPathPrefix +
+                     std::to_string(postcodeDataHolderObj.node)
               << std::endl;
     fs::create_directories(dir);
     postCodes.clear();