Reuse common choice values

8 files changed, 129 insertions, 23 deletions

diff --git a/paludis/repositories/e/e_choice_value.cc b/paludis/repositories/e/e_choice_value.cc
index 2251efa97..a89866fb2 100644
--- a/paludis/repositories/e/e_choice_value.cc
+++ b/paludis/repositories/e/e_choice_value.cc
@@ -20,10 +20,38 @@
 #include <paludis/repositories/e/e_choice_value.hh>
 #include <paludis/repositories/e/use_desc.hh>
 #include <paludis/util/make_null_shared_ptr.hh>
+#include <paludis/util/hashes.hh>
+#include <paludis/util/mutex.hh>
+#include <paludis/util/pimp-impl.hh>
+#include <paludis/util/singleton-impl.hh>
+#include <unordered_map>
 
 using namespace paludis;
 using namespace paludis::erepository;
 
+namespace
+{
+    class EChoiceValue :
+        public ChoiceValue
+    {
+        private:
+            const EChoiceValueParams _params;
+
+        public:
+            EChoiceValue(const EChoiceValueParams &);
+
+            const UnprefixedChoiceName unprefixed_name() const;
+            const ChoiceNameWithPrefix name_with_prefix() const;
+            bool enabled() const;
+            bool enabled_by_default() const;
+            bool locked() const;
+            const std::string description() const;
+            bool explicitly_listed() const;
+            const std::string parameter() const PALUDIS_ATTRIBUTE((warn_unused_result));
+            const std::shared_ptr<const PermittedChoiceValueParameterValues> permitted_parameter_values() const PALUDIS_ATTRIBUTE((warn_unused_result));
+    };
+}
+
 EChoiceValue::EChoiceValue(const EChoiceValueParams & p) :
     _params(p)
 {
@@ -83,3 +111,82 @@ EChoiceValue::permitted_parameter_values() const
     return make_null_shared_ptr();
 }
 
+namespace
+{
+    struct EChoiceValueParamsHash
+    {
+        Hash<ChoiceNameWithPrefix> choice_name_with_prefix_hash;
+        Hash<ChoicePrefixName> choice_prefix_name_hash;
+        Hash<std::string> description_hash;
+        Hash<bool> enabled_hash;
+        Hash<bool> enabled_by_default_hash;
+        Hash<bool> explicitly_listed_hash;
+        Hash<bool> locked_hash;
+        Hash<UnprefixedChoiceName> unprefixed_choice_name_hash;
+
+        std::size_t operator() (const EChoiceValueParams & p) const
+        {
+            return 0
+                ^ choice_name_with_prefix_hash(p.choice_name_with_prefix())
+                ^ choice_prefix_name_hash(p.choice_prefix_name())
+                ^ description_hash(p.description())
+                ^ enabled_hash(p.enabled())
+                ^ enabled_by_default_hash(p.enabled_by_default())
+                ^ explicitly_listed_hash(p.explicitly_listed())
+                ^ locked_hash(p.locked())
+                ^ unprefixed_choice_name_hash(p.unprefixed_choice_name())
+                ;
+        }
+    };
+
+    struct EChoiceValueParamsCompare
+    {
+        bool operator() (const EChoiceValueParams & a, const EChoiceValueParams & b) const
+        {
+            return true
+                && (a.choice_name_with_prefix() == b.choice_name_with_prefix())
+                && (a.choice_prefix_name() == b.choice_prefix_name())
+                && (a.description() == b.description())
+                && (a.enabled() == b.enabled())
+                && (a.enabled_by_default() == b.enabled_by_default())
+                && (a.explicitly_listed() == b.explicitly_listed())
+                && (a.locked() == b.locked())
+                && (a.unprefixed_choice_name() == b.unprefixed_choice_name())
+                ;
+        }
+    };
+
+    typedef std::unordered_map<EChoiceValueParams, std::shared_ptr<const EChoiceValue>, EChoiceValueParamsHash, EChoiceValueParamsCompare> Store;
+}
+
+namespace paludis
+{
+    template <>
+    struct Imp<EChoiceValueStore>
+    {
+        mutable Mutex mutex;
+        mutable Store store;
+    };
+}
+
+EChoiceValueStore::EChoiceValueStore() :
+    _imp()
+{
+}
+
+EChoiceValueStore::~EChoiceValueStore() = default;
+
+const std::shared_ptr<const ChoiceValue>
+EChoiceValueStore::fetch(const EChoiceValueParams & p) const
+{
+    Lock lock(_imp->mutex);
+    auto i(_imp->store.find(p));
+    if (i == _imp->store.end())
+        i = _imp->store.insert(std::make_pair(p, std::make_shared<EChoiceValue>(p))).first;
+
+    return i->second;
+}
+
+template class Pimp<erepository::EChoiceValueStore>;
+template class Singleton<erepository::EChoiceValueStore>;
+
diff --git a/paludis/repositories/e/e_choice_value.hh b/paludis/repositories/e/e_choice_value.hh
index 5f65656fb..829cb3cab 100644
--- a/paludis/repositories/e/e_choice_value.hh
+++ b/paludis/repositories/e/e_choice_value.hh
@@ -22,6 +22,7 @@
 
 #include <paludis/util/attributes.hh>
 #include <paludis/util/named_value.hh>
+#include <paludis/util/singleton.hh>
 #include <paludis/choice.hh>
 #include <paludis/name.hh>
 #include <functional>
@@ -55,26 +56,24 @@ namespace paludis
             NamedValue<n::unprefixed_choice_name, UnprefixedChoiceName> unprefixed_choice_name;
         };
 
-        class PALUDIS_VISIBLE EChoiceValue :
-            public ChoiceValue
+        class PALUDIS_VISIBLE EChoiceValueStore :
+            public Singleton<EChoiceValueStore>
         {
+            friend class Singleton<EChoiceValueStore>;
+
             private:
-                const EChoiceValueParams _params;
+                EChoiceValueStore();
+                ~EChoiceValueStore();
 
-            public:
-                EChoiceValue(const EChoiceValueParams &);
+                Pimp<EChoiceValueStore> _imp;
 
-                const UnprefixedChoiceName unprefixed_name() const;
-                const ChoiceNameWithPrefix name_with_prefix() const;
-                bool enabled() const;
-                bool enabled_by_default() const;
-                bool locked() const;
-                const std::string description() const;
-                bool explicitly_listed() const;
-                const std::string parameter() const PALUDIS_ATTRIBUTE((warn_unused_result));
-                const std::shared_ptr<const PermittedChoiceValueParameterValues> permitted_parameter_values() const PALUDIS_ATTRIBUTE((warn_unused_result));
+            public:
+                const std::shared_ptr<const ChoiceValue> fetch(const EChoiceValueParams &) const PALUDIS_ATTRIBUTE((warn_unused_result));
         };
     }
+
+    extern template class Pimp<erepository::EChoiceValueStore>;
+    extern template class Singleton<erepository::EChoiceValueStore>;
 }
 
 #endif
diff --git a/paludis/repositories/e/e_choices_key.cc b/paludis/repositories/e/e_choices_key.cc
index 89635a490..b4d55efab 100644
--- a/paludis/repositories/e/e_choices_key.cc
+++ b/paludis/repositories/e/e_choices_key.cc
@@ -185,7 +185,7 @@ namespace
         }
     };
 
-    std::shared_ptr<ChoiceValue> make_myoption(
+    std::shared_ptr<const ChoiceValue> make_myoption(
             const std::shared_ptr<const ERepositoryID> & id,
             std::shared_ptr<Choice> & choice,
             const UnprefixedChoiceName & unprefixed,
diff --git a/paludis/repositories/e/e_installed_repository_id.cc b/paludis/repositories/e/e_installed_repository_id.cc
index c33464fd5..d2e7bb604 100644
--- a/paludis/repositories/e/e_installed_repository_id.cc
+++ b/paludis/repositories/e/e_installed_repository_id.cc
@@ -1042,7 +1042,7 @@ EInstalledRepositoryID::slot_key() const
     return _imp->keys->slot;
 }
 
-std::shared_ptr<ChoiceValue>
+const std::shared_ptr<const ChoiceValue>
 EInstalledRepositoryID::make_choice_value(const std::shared_ptr<const Choice> & c, const UnprefixedChoiceName & v,
         const Tribool, const bool, const bool explicitly_listed, const std::string & override_description, const bool) const
 {
@@ -1064,7 +1064,7 @@ EInstalledRepositoryID::make_choice_value(const std::shared_ptr<const Choice> &
     if (raw_use_key())
         enabled = (raw_use_key()->value()->end() != raw_use_key()->value()->find(name_with_prefix));
 
-    return std::make_shared<EChoiceValue>(make_named_values<EChoiceValueParams>(
+    return EChoiceValueStore::get_instance()->fetch(make_named_values<EChoiceValueParams>(
                 n::choice_name_with_prefix() = ChoiceNameWithPrefix(name_with_prefix),
                 n::choice_prefix_name() = c->prefix(),
                 n::description() = override_description,
diff --git a/paludis/repositories/e/e_installed_repository_id.hh b/paludis/repositories/e/e_installed_repository_id.hh
index 7d4765f4e..954187dcf 100644
--- a/paludis/repositories/e/e_installed_repository_id.hh
+++ b/paludis/repositories/e/e_installed_repository_id.hh
@@ -106,7 +106,7 @@ namespace paludis
                 virtual std::string contents_filename() const = 0;
                 virtual std::shared_ptr<MetadataValueKey<std::shared_ptr<const Contents> > > make_contents_key() const = 0;
 
-                virtual std::shared_ptr<ChoiceValue> make_choice_value(
+                virtual const std::shared_ptr<const ChoiceValue> make_choice_value(
                         const std::shared_ptr<const Choice> &, const UnprefixedChoiceName &, const Tribool,
                         const bool, const bool, const std::string &, const bool) const;
 
diff --git a/paludis/repositories/e/e_repository_id.hh b/paludis/repositories/e/e_repository_id.hh
index 6fd3f8c62..27129f40b 100644
--- a/paludis/repositories/e/e_repository_id.hh
+++ b/paludis/repositories/e/e_repository_id.hh
@@ -1,7 +1,7 @@
 /* vim: set sw=4 sts=4 et foldmethod=syntax : */
 
 /*
- * Copyright (c) 2007, 2008, 2009, 2010 Ciaran McCreesh
+ * Copyright (c) 2007, 2008, 2009, 2010, 2011 Ciaran McCreesh
  *
  * This file is part of the Paludis package manager. Paludis is free software;
  * you can redistribute it and/or modify it under the terms of the GNU General
@@ -48,7 +48,7 @@ namespace paludis
 
                 virtual std::shared_ptr<const Set<std::string> > breaks_portage() const PALUDIS_ATTRIBUTE((warn_unused_result));
 
-                virtual std::shared_ptr<ChoiceValue> make_choice_value(
+                virtual const std::shared_ptr<const ChoiceValue> make_choice_value(
                         const std::shared_ptr<const Choice> &, const UnprefixedChoiceName &, const Tribool,
                         const bool, const bool, const std::string &, const bool)
                     const PALUDIS_ATTRIBUTE((warn_unused_result)) = 0;
diff --git a/paludis/repositories/e/ebuild_id.cc b/paludis/repositories/e/ebuild_id.cc
index 83519d430..c34d07fe8 100644
--- a/paludis/repositories/e/ebuild_id.cc
+++ b/paludis/repositories/e/ebuild_id.cc
@@ -1419,7 +1419,7 @@ namespace
 }
 
 
-std::shared_ptr<ChoiceValue>
+const std::shared_ptr<const ChoiceValue>
 EbuildID::make_choice_value(
         const std::shared_ptr<const Choice> & choice,
         const UnprefixedChoiceName & value_name,
@@ -1498,7 +1498,7 @@ EbuildID::make_choice_value(
         }
     }
 
-    return std::make_shared<EChoiceValue>(make_named_values<EChoiceValueParams>(
+    return EChoiceValueStore::get_instance()->fetch(make_named_values<EChoiceValueParams>(
                 n::choice_name_with_prefix() = ChoiceNameWithPrefix(name_with_prefix),
                 n::choice_prefix_name() = choice->prefix(),
                 n::description() = get_description(e_repo->use_desc(), override_description, name(), choice->prefix(), value_name),
diff --git a/paludis/repositories/e/ebuild_id.hh b/paludis/repositories/e/ebuild_id.hh
index ab9c73493..21af84003 100644
--- a/paludis/repositories/e/ebuild_id.hh
+++ b/paludis/repositories/e/ebuild_id.hh
@@ -158,7 +158,7 @@ namespace paludis
 
                 virtual void invalidate_masks() const;
 
-                virtual std::shared_ptr<ChoiceValue> make_choice_value(
+                virtual const std::shared_ptr<const ChoiceValue> make_choice_value(
                         const std::shared_ptr<const Choice> &, const UnprefixedChoiceName &, const Tribool,
                         const bool, const bool, const std::string &, const bool) const;