From fa32560169ffa55b9e0b6d5f04c3792acf0c544a Mon Sep 17 00:00:00 2001
From: regnat <rg@regnat.ovh>
Date: Wed, 9 Sep 2020 11:18:12 +0200
Subject: [PATCH] Fix the registration of stores

---
 src/libstore/dummy-store.cc              |  2 +-
 src/libstore/http-binary-cache-store.cc  |  2 +-
 src/libstore/legacy-ssh-store.cc         |  2 +-
 src/libstore/local-binary-cache-store.cc |  2 +-
 src/libstore/remote-store.cc             |  2 +-
 src/libstore/s3-binary-cache-store.cc    |  2 +-
 src/libstore/ssh-store.cc                |  2 +-
 src/libstore/store-api.cc                |  3 ++-
 src/libstore/store-api.hh                | 29 +++++++++++++++---------
 9 files changed, 27 insertions(+), 19 deletions(-)

diff --git a/src/libstore/dummy-store.cc b/src/libstore/dummy-store.cc
index a677e201e..dd1880877 100644
--- a/src/libstore/dummy-store.cc
+++ b/src/libstore/dummy-store.cc
@@ -50,6 +50,6 @@ struct DummyStore : public Store
     { unsupported("buildDerivation"); }
 };
 
-[[maybe_unused]] static RegisterStoreImplementation<DummyStore> regStore();
+static RegisterStoreImplementation<DummyStore> regStore;
 
 }
diff --git a/src/libstore/http-binary-cache-store.cc b/src/libstore/http-binary-cache-store.cc
index 6c3a16faf..c1abe35cb 100644
--- a/src/libstore/http-binary-cache-store.cc
+++ b/src/libstore/http-binary-cache-store.cc
@@ -170,6 +170,6 @@ protected:
 
 };
 
-[[maybe_unused]] static RegisterStoreImplementation<HttpBinaryCacheStore> regStore();
+static RegisterStoreImplementation<HttpBinaryCacheStore> regStore;
 
 }
diff --git a/src/libstore/legacy-ssh-store.cc b/src/libstore/legacy-ssh-store.cc
index 72f28a82d..552b4b176 100644
--- a/src/libstore/legacy-ssh-store.cc
+++ b/src/libstore/legacy-ssh-store.cc
@@ -326,6 +326,6 @@ public:
     }
 };
 
-[[maybe_unused]] static RegisterStoreImplementation<LegacySSHStore> regStore();
+static RegisterStoreImplementation<LegacySSHStore> regStore;
 
 }
diff --git a/src/libstore/local-binary-cache-store.cc b/src/libstore/local-binary-cache-store.cc
index 752838d3f..808a1338f 100644
--- a/src/libstore/local-binary-cache-store.cc
+++ b/src/libstore/local-binary-cache-store.cc
@@ -96,6 +96,6 @@ std::vector<std::string> LocalBinaryCacheStore::uriPrefixes()
         return {"file"};
 }
 
-[[maybe_unused]] static RegisterStoreImplementation<LocalBinaryCacheStore> regStore();
+static RegisterStoreImplementation<LocalBinaryCacheStore> regStore;
 
 }
diff --git a/src/libstore/remote-store.cc b/src/libstore/remote-store.cc
index 824b6b140..5f455a62a 100644
--- a/src/libstore/remote-store.cc
+++ b/src/libstore/remote-store.cc
@@ -982,6 +982,6 @@ std::exception_ptr RemoteStore::Connection::processStderr(Sink * sink, Source *
     return nullptr;
 }
 
-[[maybe_unused]] static RegisterStoreImplementation<UDSRemoteStore> regStore();
+static RegisterStoreImplementation<UDSRemoteStore> regStore;
 
 }
diff --git a/src/libstore/s3-binary-cache-store.cc b/src/libstore/s3-binary-cache-store.cc
index 1bf4d5955..f426b43a9 100644
--- a/src/libstore/s3-binary-cache-store.cc
+++ b/src/libstore/s3-binary-cache-store.cc
@@ -431,7 +431,7 @@ struct S3BinaryCacheStoreImpl : public S3BinaryCacheStore
 
 };
 
-[[maybe_unused]] static RegisterStoreImplementation<S3BinaryCacheStoreImpl> regStore();
+static RegisterStoreImplementation<S3BinaryCacheStoreImpl> regStore;
 
 }
 
diff --git a/src/libstore/ssh-store.cc b/src/libstore/ssh-store.cc
index 02208ee82..8177a95b0 100644
--- a/src/libstore/ssh-store.cc
+++ b/src/libstore/ssh-store.cc
@@ -76,6 +76,6 @@ ref<RemoteStore::Connection> SSHStore::openConnection()
     return conn;
 }
 
-[[maybe_unused]] static RegisterStoreImplementation<SSHStore> regStore();
+static RegisterStoreImplementation<SSHStore> regStore;
 
 }
diff --git a/src/libstore/store-api.cc b/src/libstore/store-api.cc
index 4a46b5160..0f321b434 100644
--- a/src/libstore/store-api.cc
+++ b/src/libstore/store-api.cc
@@ -1093,7 +1093,7 @@ ref<Store> openStore(const std::string & uri_,
         return ref<Store>(store);
     }
 
-    for (auto implem : *implementations) {
+    for (auto implem : *Implementations::registered) {
         auto store = implem.open(uri, params);
         if (store) {
             store->warnUnknownSettings();
@@ -1136,5 +1136,6 @@ std::list<ref<Store>> getDefaultSubstituters()
     return stores;
 }
 
+std::vector<StoreFactory> * Implementations::registered = 0;
 
 }
diff --git a/src/libstore/store-api.hh b/src/libstore/store-api.hh
index 28365542d..61080978e 100644
--- a/src/libstore/store-api.hh
+++ b/src/libstore/store-api.hh
@@ -749,25 +749,32 @@ std::list<ref<Store>> getDefaultSubstituters();
 
 struct StoreFactory
 {
-    std::vector<std::string> uriPrefixes;
     std::function<std::shared_ptr<Store> (const std::string & uri, const Store::Params & params)> open;
 };
-typedef std::vector<StoreFactory> Implementations;
-static Implementations * implementations = new Implementations;
+struct Implementations
+{
+    static std::vector<StoreFactory> * registered;
+
+    template<typename T>
+    static void add()
+    {
+        if (!registered) registered = new std::vector<StoreFactory>();
+        StoreFactory factory{
+            .open =
+                ([](const std::string & uri, const Store::Params & params)
+                 -> std::shared_ptr<Store>
+                 { return std::make_shared<T>(uri, params); }),
+        };
+        registered->push_back(factory);
+    }
+};
 
 template<typename T>
 struct RegisterStoreImplementation
 {
     RegisterStoreImplementation()
     {
-        StoreFactory factory{
-            .uriPrefixes = T::uriPrefixes(),
-            .open =
-                ([](const std::string & uri, const Store::Params & params)
-                 -> std::shared_ptr<Store>
-                 { return std::make_shared<T>(uri, params); })
-        };
-        implementations->push_back(factory);
+        Implementations::add<T>();
     }
 };