Add GemcutterRepository

18 files changed, 1664 insertions, 0 deletions

diff --git a/paludis/repositories/gemcutter/Makefile.am b/paludis/repositories/gemcutter/Makefile.am
new file mode 100644
index 000000000..5c2fe6e30
--- /dev/null
+++ b/paludis/repositories/gemcutter/Makefile.am
@@ -0,0 +1,36 @@
+include $(top_srcdir)/misc/common-makefile.am
+
+SUBDIRS = .
+
+AM_CXXFLAGS = -I$(top_srcdir) -I$(top_builddir) @PALUDIS_CXXFLAGS@ @PALUDIS_CXXFLAGS_VISIBILITY@
+DEFS= \
+	-DSYSCONFDIR=\"$(sysconfdir)\" \
+	-DLIBEXECDIR=\"$(libexecdir)\" \
+	-DDATADIR=\"$(datadir)\" \
+	-DLIBDIR=\"$(libdir)\"
+
+noinst_LTLIBRARIES = libpaludisgemcutterrepository.la
+
+noinst_HEADERS = \
+	gemcutter_id.hh gemcutter_id-fwd.hh \
+	gemcutter_repository.hh gemcutter_repository-fwd.hh \
+	gemcutter_repository_store.hh \
+	json_common.hh json_common-fwd.hh \
+	json_things_handle.hh json_things_handle-fwd.hh
+
+libpaludisgemcutterrepository_la_SOURCES = \
+	gemcutter_id.cc \
+	gemcutter_repository.cc \
+	gemcutter_repository_store.cc \
+	json_common.cc \
+	json_things_handle.cc \
+	registration.cc \
+	$(noinst_HEADERS)
+
+lib_LTLIBRARIES = libpaludisgemcutterrepositoryjsonthings_@PALUDIS_PC_SLOT@.la
+
+libpaludisgemcutterrepositoryjsonthings_@PALUDIS_PC_SLOT@_la_SOURCES = json_things.cc json_things.hh
+libpaludisgemcutterrepositoryjsonthings_@PALUDIS_PC_SLOT@_la_CXXFLAGS = $(AM_CXXFLAGS) @JANSSONDEPS_CFLAGS@
+libpaludisgemcutterrepositoryjsonthings_@PALUDIS_PC_SLOT@_la_LIBADD = @JANSSONDEPS_LIBS@
+libpaludisgemcutterrepositoryjsonthings_@PALUDIS_PC_SLOT@_la_LDFLAGS = -version-info @VERSION_LIB_CURRENT@:@VERSION_LIB_REVISION@:0
+
diff --git a/paludis/repositories/gemcutter/gemcutter_id-fwd.hh b/paludis/repositories/gemcutter/gemcutter_id-fwd.hh
new file mode 100644
index 000000000..afb2a7c48
--- /dev/null
+++ b/paludis/repositories/gemcutter/gemcutter_id-fwd.hh
@@ -0,0 +1,32 @@
+/* vim: set sw=4 sts=4 et foldmethod=syntax : */
+
+/*
+ * Copyright (c) 2010 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
+ * Public License version 2, as published by the Free Software Foundation.
+ *
+ * Paludis is distributed in the hope that it will be useful, but WITHOUT ANY
+ * WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS
+ * FOR A PARTICULAR PURPOSE.  See the GNU General Public License for more
+ * details.
+ *
+ * You should have received a copy of the GNU General Public License along with
+ * this program; if not, write to the Free Software Foundation, Inc., 59 Temple
+ * Place, Suite 330, Boston, MA  02111-1307  USA
+ */
+
+#ifndef PALUDIS_GUARD_PALUDIS_REPOSITORIES_GEMCUTTER_GEMCUTTER_ID_FWD_HH
+#define PALUDIS_GUARD_PALUDIS_REPOSITORIES_GEMCUTTER_GEMCUTTER_ID_FWD_HH 1
+
+namespace paludis
+{
+    namespace gemcutter_repository
+    {
+        class GemcutterID;
+        class GemcutterIDParams;
+    }
+}
+
+#endif
diff --git a/paludis/repositories/gemcutter/gemcutter_id.cc b/paludis/repositories/gemcutter/gemcutter_id.cc
new file mode 100644
index 000000000..613e42a31
--- /dev/null
+++ b/paludis/repositories/gemcutter/gemcutter_id.cc
@@ -0,0 +1,289 @@
+/* vim: set sw=4 sts=4 et foldmethod=syntax : */
+
+/*
+ * Copyright (c) 2010 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
+ * Public License version 2, as published by the Free Software Foundation.
+ *
+ * Paludis is distributed in the hope that it will be useful, but WITHOUT ANY
+ * WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS
+ * FOR A PARTICULAR PURPOSE.  See the GNU General Public License for more
+ * details.
+ *
+ * You should have received a copy of the GNU General Public License along with
+ * this program; if not, write to the Free Software Foundation, Inc., 59 Temple
+ * Place, Suite 330, Boston, MA  02111-1307  USA
+ */
+
+#include <paludis/repositories/gemcutter/gemcutter_id.hh>
+#include <paludis/repositories/gemcutter/gemcutter_repository.hh>
+#include <paludis/util/pimp-impl.hh>
+#include <paludis/util/stringify.hh>
+#include <paludis/util/simple_visitor_cast.hh>
+#include <paludis/util/set.hh>
+#include <paludis/util/hashes.hh>
+#include <paludis/util/wrapped_forward_iterator.hh>
+#include <paludis/util/make_null_shared_ptr.hh>
+#include <paludis/util/singleton-impl.hh>
+#include <paludis/name.hh>
+#include <paludis/version_spec.hh>
+#include <paludis/metadata_key.hh>
+#include <paludis/literal_metadata_key.hh>
+#include <paludis/action.hh>
+#include <paludis/unchoices_key.hh>
+#include <paludis/user_dep_spec.hh>
+
+using namespace paludis;
+using namespace paludis::gemcutter_repository;
+
+namespace paludis
+{
+    template <>
+    struct Imp<GemcutterID>
+    {
+        const Environment * const env;
+        const QualifiedPackageName name;
+        const VersionSpec version;
+        const GemcutterRepository * const repo;
+
+        Imp(const GemcutterIDParams & e) :
+            env(e.environment()),
+            name(CategoryNamePart("gem"), PackageNamePart(e.info().name())),
+            version(e.info().version(), { }),
+            repo(e.repository())
+        {
+        }
+    };
+}
+
+GemcutterID::GemcutterID(const GemcutterIDParams & entry) :
+    Pimp<GemcutterID>(entry),
+    _imp(Pimp<GemcutterID>::_imp)
+{
+}
+
+GemcutterID::~GemcutterID()
+{
+}
+
+void
+GemcutterID::need_keys_added() const
+{
+}
+
+void
+GemcutterID::need_masks_added() const
+{
+}
+
+const std::string
+GemcutterID::canonical_form(const PackageIDCanonicalForm f) const
+{
+    switch (f)
+    {
+        case idcf_full:
+            return stringify(_imp->name) + "-" + stringify(_imp->version) +
+                "::" + stringify(_imp->repo->name());
+
+        case idcf_no_version:
+            return stringify(_imp->name) + "::" + stringify(_imp->repo->name());
+
+        case idcf_version:
+            return stringify(_imp->version);
+
+        case idcf_no_name:
+            return stringify(_imp->version) + "::" + stringify(_imp->repo->name());
+
+        case last_idcf:
+            break;
+    }
+
+    throw InternalError(PALUDIS_HERE, "Bad PackageIDCanonicalForm");
+}
+
+PackageDepSpec
+GemcutterID::uniquely_identifying_spec() const
+{
+    return parse_user_package_dep_spec("=" + stringify(name()) + "-" + stringify(version()) +
+            + "::" + stringify(repository()->name()),
+            _imp->env, { });
+}
+
+const QualifiedPackageName
+GemcutterID::name() const
+{
+    return _imp->name;
+}
+
+const VersionSpec
+GemcutterID::version() const
+{
+    return _imp->version;
+}
+
+const std::shared_ptr<const Repository>
+GemcutterID::repository() const
+{
+    return _imp->repo->shared_from_this();
+}
+
+bool
+GemcutterID::supports_action(const SupportsActionTestBase &) const
+{
+    return false;
+}
+
+void
+GemcutterID::perform_action(Action & a) const
+{
+    throw ActionFailedError("Unsupported action: " + a.simple_name());
+}
+
+std::shared_ptr<const Set<std::string> >
+GemcutterID::breaks_portage() const
+{
+    return std::make_shared<Set<std::string>>();
+}
+
+bool
+GemcutterID::arbitrary_less_than_comparison(const PackageID &) const
+{
+    return false;
+}
+
+std::size_t
+GemcutterID::extra_hash_value() const
+{
+    return 0;
+}
+
+const std::shared_ptr<const MetadataCollectionKey<PackageIDSequence> >
+GemcutterID::contains_key() const
+{
+    return std::shared_ptr<const MetadataCollectionKey<PackageIDSequence> >();
+}
+
+const std::shared_ptr<const MetadataValueKey<std::shared_ptr<const PackageID> > >
+GemcutterID::contained_in_key() const
+{
+    return std::shared_ptr<const MetadataValueKey<std::shared_ptr<const PackageID> > >();
+}
+
+const std::shared_ptr<const MetadataValueKey<FSPath> >
+GemcutterID::fs_location_key() const
+{
+    return std::shared_ptr<const MetadataValueKey<FSPath> >();
+}
+
+const std::shared_ptr<const MetadataCollectionKey<Set<std::string> > >
+GemcutterID::behaviours_key() const
+{
+    return make_null_shared_ptr();
+}
+
+const std::shared_ptr<const MetadataValueKey<std::shared_ptr<const PackageID> > >
+GemcutterID::virtual_for_key() const
+{
+    return std::shared_ptr<const MetadataValueKey<std::shared_ptr<const PackageID> > >();
+}
+
+const std::shared_ptr<const MetadataCollectionKey<KeywordNameSet> >
+GemcutterID::keywords_key() const
+{
+    return std::shared_ptr<const MetadataCollectionKey<KeywordNameSet> >();
+}
+
+const std::shared_ptr<const MetadataSpecTreeKey<ProvideSpecTree> >
+GemcutterID::provide_key() const
+{
+    return std::shared_ptr<const MetadataSpecTreeKey<ProvideSpecTree> >();
+}
+
+const std::shared_ptr<const MetadataSpecTreeKey<DependencySpecTree> >
+GemcutterID::dependencies_key() const
+{
+    return std::shared_ptr<const MetadataSpecTreeKey<DependencySpecTree> >();
+}
+
+const std::shared_ptr<const MetadataSpecTreeKey<DependencySpecTree> >
+GemcutterID::build_dependencies_key() const
+{
+    return std::shared_ptr<const MetadataSpecTreeKey<DependencySpecTree> >();
+}
+
+const std::shared_ptr<const MetadataSpecTreeKey<DependencySpecTree> >
+GemcutterID::run_dependencies_key() const
+{
+    return std::shared_ptr<const MetadataSpecTreeKey<DependencySpecTree> >();
+}
+
+const std::shared_ptr<const MetadataSpecTreeKey<DependencySpecTree> >
+GemcutterID::post_dependencies_key() const
+{
+    return std::shared_ptr<const MetadataSpecTreeKey<DependencySpecTree> >();
+}
+
+const std::shared_ptr<const MetadataSpecTreeKey<DependencySpecTree> >
+GemcutterID::suggested_dependencies_key() const
+{
+    return std::shared_ptr<const MetadataSpecTreeKey<DependencySpecTree> >();
+}
+
+const std::shared_ptr<const MetadataValueKey<std::string> >
+GemcutterID::short_description_key() const
+{
+    return make_null_shared_ptr();
+}
+
+const std::shared_ptr<const MetadataValueKey<std::string> >
+GemcutterID::long_description_key() const
+{
+    return std::shared_ptr<const MetadataValueKey<std::string> >();
+}
+
+const std::shared_ptr<const MetadataSpecTreeKey<FetchableURISpecTree> >
+GemcutterID::fetches_key() const
+{
+    return std::shared_ptr<const MetadataSpecTreeKey<FetchableURISpecTree> >();
+}
+
+const std::shared_ptr<const MetadataSpecTreeKey<SimpleURISpecTree> >
+GemcutterID::homepage_key() const
+{
+    return std::shared_ptr<const MetadataSpecTreeKey<SimpleURISpecTree> >();
+}
+
+const std::shared_ptr<const MetadataValueKey<std::shared_ptr<const Contents> > >
+GemcutterID::contents_key() const
+{
+    return std::shared_ptr<const MetadataValueKey<std::shared_ptr<const Contents> > >();
+}
+
+const std::shared_ptr<const MetadataTimeKey>
+GemcutterID::installed_time_key() const
+{
+    return std::shared_ptr<const MetadataTimeKey>();
+}
+
+const std::shared_ptr<const MetadataCollectionKey<Set<std::string> > >
+GemcutterID::from_repositories_key() const
+{
+    return make_null_shared_ptr();
+}
+
+const std::shared_ptr<const MetadataValueKey<std::shared_ptr<const Choices> > >
+GemcutterID::choices_key() const
+{
+    return make_null_shared_ptr();
+}
+
+const std::shared_ptr<const MetadataValueKey<SlotName> >
+GemcutterID::slot_key() const
+{
+    return make_null_shared_ptr();
+}
+
+template class Pimp<GemcutterID>;
+
diff --git a/paludis/repositories/gemcutter/gemcutter_id.hh b/paludis/repositories/gemcutter/gemcutter_id.hh
new file mode 100644
index 000000000..a0b7afd6c
--- /dev/null
+++ b/paludis/repositories/gemcutter/gemcutter_id.hh
@@ -0,0 +1,115 @@
+/* vim: set sw=4 sts=4 et foldmethod=syntax : */
+
+/*
+ * Copyright (c) 2010 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
+ * Public License version 2, as published by the Free Software Foundation.
+ *
+ * Paludis is distributed in the hope that it will be useful, but WITHOUT ANY
+ * WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS
+ * FOR A PARTICULAR PURPOSE.  See the GNU General Public License for more
+ * details.
+ *
+ * You should have received a copy of the GNU General Public License along with
+ * this program; if not, write to the Free Software Foundation, Inc., 59 Temple
+ * Place, Suite 330, Boston, MA  02111-1307  USA
+ */
+
+#ifndef PALUDIS_GUARD_PALUDIS_REPOSITORIES_GEMCUTTER_GEMCUTTER_ID_HH
+#define PALUDIS_GUARD_PALUDIS_REPOSITORIES_GEMCUTTER_GEMCUTTER_ID_HH 1
+
+#include <paludis/repositories/gemcutter/gemcutter_id-fwd.hh>
+#include <paludis/repositories/gemcutter/gemcutter_repository-fwd.hh>
+#include <paludis/repositories/gemcutter/json_common.hh>
+#include <paludis/util/named_value.hh>
+#include <paludis/package_id.hh>
+#include <paludis/name.hh>
+
+namespace paludis
+{
+    namespace n
+    {
+        typedef Name<struct environment_name> environment;
+        typedef Name<struct info_name> info;
+        typedef Name<struct repository_name> repository;
+    }
+
+    namespace gemcutter_repository
+    {
+        struct GemcutterIDParams
+        {
+            NamedValue<n::environment, const Environment *> environment;
+            NamedValue<n::info, GemJSONInfo> info;
+            NamedValue<n::repository, const GemcutterRepository *> repository;
+        };
+
+        class PALUDIS_VISIBLE GemcutterID :
+            public PackageID,
+            private Pimp<GemcutterID>
+        {
+            private:
+                Pimp<GemcutterID>::ImpPtr & _imp;
+
+            protected:
+                void need_keys_added() const;
+                void need_masks_added() const;
+
+            public:
+                GemcutterID(const GemcutterIDParams &);
+                ~GemcutterID();
+
+                 const std::string canonical_form(const PackageIDCanonicalForm) const;
+                 const QualifiedPackageName name() const;
+                 const VersionSpec version() const;
+                 const std::shared_ptr<const Repository> repository() const;
+                 virtual PackageDepSpec uniquely_identifying_spec() const;
+
+                 const std::shared_ptr<const MetadataValueKey<SlotName> > slot_key() const;
+                 const std::shared_ptr<const MetadataValueKey<std::shared_ptr<const PackageID> > >
+                     virtual_for_key() const;
+                 const std::shared_ptr<const MetadataCollectionKey<KeywordNameSet> > keywords_key() const;
+                 const std::shared_ptr<const MetadataSpecTreeKey<ProvideSpecTree> > provide_key() const;
+                 const std::shared_ptr<const MetadataCollectionKey<PackageIDSequence> > contains_key() const;
+                 const std::shared_ptr<const MetadataValueKey<std::shared_ptr<const PackageID> > >
+                     contained_in_key() const;
+                 const std::shared_ptr<const MetadataSpecTreeKey<DependencySpecTree> >
+                     dependencies_key() const;
+                 const std::shared_ptr<const MetadataSpecTreeKey<DependencySpecTree> >
+                     build_dependencies_key() const;
+                 const std::shared_ptr<const MetadataSpecTreeKey<DependencySpecTree> >
+                     run_dependencies_key() const;
+                 const std::shared_ptr<const MetadataSpecTreeKey<DependencySpecTree> >
+                     post_dependencies_key() const;
+                 const std::shared_ptr<const MetadataSpecTreeKey<DependencySpecTree> >
+                     suggested_dependencies_key() const;
+                 const std::shared_ptr<const MetadataSpecTreeKey<FetchableURISpecTree> > fetches_key() const;
+                 const std::shared_ptr<const MetadataSpecTreeKey<SimpleURISpecTree> > homepage_key() const;
+                 const std::shared_ptr<const MetadataValueKey<std::string> > short_description_key() const;
+                 const std::shared_ptr<const MetadataValueKey<std::string> > long_description_key() const;
+                 const std::shared_ptr<const MetadataValueKey<std::shared_ptr<const Contents> > >
+                     contents_key() const;
+                 const std::shared_ptr<const MetadataTimeKey> installed_time_key() const;
+                 const std::shared_ptr<const MetadataValueKey<FSPath> > fs_location_key() const;
+                 const std::shared_ptr<const MetadataCollectionKey<Set<std::string> > > behaviours_key() const;
+                 const std::shared_ptr<const MetadataCollectionKey<Set<std::string> > > from_repositories_key() const;
+                 const std::shared_ptr<const MetadataValueKey<std::shared_ptr<const Choices> > > choices_key() const;
+
+                 bool supports_action(const SupportsActionTestBase &) const
+                     PALUDIS_ATTRIBUTE((warn_unused_result));
+                 void perform_action(Action &) const PALUDIS_ATTRIBUTE((noreturn));
+
+                 std::shared_ptr<const Set<std::string> > breaks_portage() const
+                     PALUDIS_ATTRIBUTE((warn_unused_result));
+
+                 bool arbitrary_less_than_comparison(const PackageID &) const
+                    PALUDIS_ATTRIBUTE((warn_unused_result));
+                 std::size_t extra_hash_value() const
+                    PALUDIS_ATTRIBUTE((warn_unused_result));
+        };
+
+    }
+}
+
+#endif
diff --git a/paludis/repositories/gemcutter/gemcutter_repository-fwd.hh b/paludis/repositories/gemcutter/gemcutter_repository-fwd.hh
new file mode 100644
index 000000000..e2135295f
--- /dev/null
+++ b/paludis/repositories/gemcutter/gemcutter_repository-fwd.hh
@@ -0,0 +1,31 @@
+/* vim: set sw=4 sts=4 et foldmethod=syntax : */
+
+/*
+ * Copyright (c) 2010 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
+ * Public License version 2, as published by the Free Software Foundation.
+ *
+ * Paludis is distributed in the hope that it will be useful, but WITHOUT ANY
+ * WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS
+ * FOR A PARTICULAR PURPOSE.  See the GNU General Public License for more
+ * details.
+ *
+ * You should have received a copy of the GNU General Public License along with
+ * this program; if not, write to the Free Software Foundation, Inc., 59 Temple
+ * Place, Suite 330, Boston, MA  02111-1307  USA
+ */
+
+#ifndef PALUDIS_GUARD_PALUDIS_REPOSITORIES_GEMCUTTER_GEMCUTTER_REPOSITORY_FWD_HH
+#define PALUDIS_GUARD_PALUDIS_REPOSITORIES_GEMCUTTER_GEMCUTTER_REPOSITORY_FWD_HH 1
+
+namespace paludis
+{
+    namespace gemcutter_repository
+    {
+        class GemcutterRepository;
+    }
+}
+
+#endif
diff --git a/paludis/repositories/gemcutter/gemcutter_repository.cc b/paludis/repositories/gemcutter/gemcutter_repository.cc
new file mode 100644
index 000000000..934ff56bd
--- /dev/null
+++ b/paludis/repositories/gemcutter/gemcutter_repository.cc
@@ -0,0 +1,327 @@
+/* vim: set sw=4 sts=4 et foldmethod=syntax : */
+
+/*
+ * Copyright (c) 2010 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
+ * Public License version 2, as published by the Free Software Foundation.
+ *
+ * Paludis is distributed in the hope that it will be useful, but WITHOUT ANY
+ * WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS
+ * FOR A PARTICULAR PURPOSE.  See the GNU General Public License for more
+ * details.
+ *
+ * You should have received a copy of the GNU General Public License along with
+ * this program; if not, write to the Free Software Foundation, Inc., 59 Temple
+ * Place, Suite 330, Boston, MA  02111-1307  USA
+ */
+
+#include <paludis/repositories/gemcutter/gemcutter_repository.hh>
+#include <paludis/repositories/gemcutter/gemcutter_repository_store.hh>
+#include <paludis/util/pimp-impl.hh>
+#include <paludis/util/active_object_ptr.hh>
+#include <paludis/util/deferred_construction_ptr.hh>
+#include <paludis/util/stringify.hh>
+#include <paludis/util/tokeniser.hh>
+#include <paludis/util/make_named_values.hh>
+#include <paludis/util/simple_visitor_cast.hh>
+#include <paludis/util/simple_parser.hh>
+#include <paludis/util/safe_ifstream.hh>
+#include <paludis/util/safe_ofstream.hh>
+#include <paludis/util/make_null_shared_ptr.hh>
+#include <paludis/util/fs_stat.hh>
+#include <paludis/literal_metadata_key.hh>
+#include <paludis/action.hh>
+#include <paludis/syncer.hh>
+#include <paludis/hook.hh>
+#include <paludis/package_id.hh>
+#include <paludis/output_manager.hh>
+#include <paludis/environment.hh>
+#include <list>
+
+using namespace paludis;
+using namespace paludis::gemcutter_repository;
+
+namespace
+{
+    std::shared_ptr<GemcutterRepositoryStore>
+    make_store(const GemcutterRepository * const repo, const GemcutterRepositoryParams & p)
+    {
+        return std::make_shared<GemcutterRepositoryStore>(p.environment(), repo, p.location());
+    }
+}
+
+namespace paludis
+{
+    template <>
+    struct Imp<GemcutterRepository>
+    {
+        const GemcutterRepositoryParams params;
+
+        const std::shared_ptr<LiteralMetadataValueKey<std::string> > format_key;
+        const std::shared_ptr<LiteralMetadataValueKey<FSPath> > location_key;
+
+        const ActiveObjectPtr<DeferredConstructionPtr<std::shared_ptr<GemcutterRepositoryStore> > > store;
+
+        Imp(const GemcutterRepository * const repo, const GemcutterRepositoryParams & p) :
+            params(p),
+            format_key(std::make_shared<LiteralMetadataValueKey<std::string> >("format", "format", mkt_significant, "gemcutter")),
+            location_key(std::make_shared<LiteralMetadataValueKey<FSPath> >("location", "location", mkt_significant, params.location())),
+            store(DeferredConstructionPtr<std::shared_ptr<GemcutterRepositoryStore> > (std::bind(&make_store, repo, std::cref(params))))
+        {
+        }
+    };
+}
+
+GemcutterRepositoryConfigurationError::GemcutterRepositoryConfigurationError(const std::string & s) throw () :
+    ConfigurationError("GemcutterRepository configuration error: " + s)
+{
+}
+
+GemcutterRepository::GemcutterRepository(const GemcutterRepositoryParams & p) :
+    Pimp<GemcutterRepository>(this, p),
+    Repository(
+            p.environment(),
+            p.name(),
+            make_named_values<RepositoryCapabilities>(
+                n::destination_interface() = static_cast<RepositoryDestinationInterface *>(0),
+                n::environment_variable_interface() = static_cast<RepositoryEnvironmentVariableInterface *>(0),
+                n::make_virtuals_interface() = static_cast<RepositoryMakeVirtualsInterface *>(0),
+                n::manifest_interface() = static_cast<RepositoryManifestInterface *>(0),
+                n::provides_interface() = static_cast<RepositoryProvidesInterface *>(0),
+                n::virtuals_interface() = static_cast<RepositoryVirtualsInterface *>(0)
+                )),
+    _imp(Pimp<GemcutterRepository>::_imp)
+{
+    _add_metadata_keys();
+}
+
+GemcutterRepository::~GemcutterRepository()
+{
+}
+
+bool
+GemcutterRepository::can_be_favourite_repository() const
+{
+    return false;
+}
+
+const bool
+GemcutterRepository::is_unimportant() const
+{
+    return false;
+}
+
+void
+GemcutterRepository::_add_metadata_keys()
+{
+    clear_metadata_keys();
+    add_metadata_key(_imp->format_key);
+    add_metadata_key(_imp->location_key);
+}
+
+void
+GemcutterRepository::need_keys_added() const
+{
+}
+
+const std::shared_ptr<const MetadataValueKey<std::string> >
+GemcutterRepository::format_key() const
+{
+    return _imp->format_key;
+}
+
+const std::shared_ptr<const MetadataValueKey<FSPath> >
+GemcutterRepository::location_key() const
+{
+    return _imp->location_key;
+}
+
+const std::shared_ptr<const MetadataValueKey<FSPath> >
+GemcutterRepository::installed_root_key() const
+{
+    return make_null_shared_ptr();
+}
+
+void
+GemcutterRepository::invalidate()
+{
+    _imp.reset(new Imp<GemcutterRepository>(this, _imp->params));
+    _add_metadata_keys();
+}
+
+void
+GemcutterRepository::invalidate_masks()
+{
+}
+
+bool
+GemcutterRepository::has_category_named(const CategoryNamePart & c) const
+{
+    return _imp->store->has_category_named(c);
+}
+
+bool
+GemcutterRepository::has_package_named(const QualifiedPackageName & q) const
+{
+    return _imp->store->has_package_named(q);
+}
+
+std::shared_ptr<const CategoryNamePartSet>
+GemcutterRepository::category_names() const
+{
+    return _imp->store->category_names();
+}
+
+std::shared_ptr<const CategoryNamePartSet>
+GemcutterRepository::unimportant_category_names() const
+{
+    return _imp->store->unimportant_category_names();
+}
+
+std::shared_ptr<const CategoryNamePartSet>
+GemcutterRepository::category_names_containing_package(const PackageNamePart & p) const
+{
+    return Repository::category_names_containing_package(p);
+}
+
+std::shared_ptr<const QualifiedPackageNameSet>
+GemcutterRepository::package_names(const CategoryNamePart & c) const
+{
+    return _imp->store->package_names(c);
+}
+
+std::shared_ptr<const PackageIDSequence>
+GemcutterRepository::package_ids(const QualifiedPackageName & p) const
+{
+    return _imp->store->package_ids(p);
+}
+
+namespace
+{
+    struct SupportsActionQuery
+    {
+        bool visit(const SupportsActionTest<InstallAction> &) const
+        {
+            return true;
+        }
+
+        bool visit(const SupportsActionTest<FetchAction> &) const
+        {
+            return true;
+        }
+
+        bool visit(const SupportsActionTest<PretendFetchAction> &) const
+        {
+            return false;
+        }
+
+        bool visit(const SupportsActionTest<ConfigAction> &) const
+        {
+            return false;
+        }
+
+        bool visit(const SupportsActionTest<PretendAction> &) const
+        {
+            return false;
+        }
+
+        bool visit(const SupportsActionTest<InfoAction> &) const
+        {
+            return false;
+        }
+
+        bool visit(const SupportsActionTest<UninstallAction> &) const
+        {
+            return false;
+        }
+    };
+}
+
+bool
+GemcutterRepository::some_ids_might_support_action(const SupportsActionTestBase & a) const
+{
+    SupportsActionQuery q;
+    return a.accept_returning<bool>(q);
+}
+
+bool
+GemcutterRepository::some_ids_might_not_be_masked() const
+{
+    return true;
+}
+
+bool
+GemcutterRepository::sync(const std::shared_ptr<OutputManager> &) const
+{
+    return false;
+}
+
+std::shared_ptr<Repository>
+GemcutterRepository::repository_factory_create(
+        Environment * const env,
+        const std::function<std::string (const std::string &)> & f)
+{
+    Context context("When making repository repository from repo_file '" + f("repo_file") + "':");
+
+    std::string name_str(f("name"));
+    if (name_str.empty())
+        name_str = "gemcutter";
+
+    std::string location_str(f("location"));
+    if (location_str.empty())
+        throw GemcutterRepositoryConfigurationError("Key 'location' not specified or empty");
+
+    return std::make_shared<GemcutterRepository>(
+            make_named_values<GemcutterRepositoryParams>(
+                n::environment() = env,
+                n::location() = FSPath(location_str),
+                n::name() = RepositoryName(name_str)
+                ));
+}
+
+RepositoryName
+GemcutterRepository::repository_factory_name(
+        const Environment * const,
+        const std::function<std::string (const std::string &)> & f)
+{
+    if (f("name").empty())
+        return RepositoryName("gemcutter");
+    else
+        return RepositoryName(f("name"));
+}
+
+std::shared_ptr<const RepositoryNameSet>
+GemcutterRepository::repository_factory_dependencies(
+        const Environment * const,
+        const std::function<std::string (const std::string &)> &)
+{
+    return std::make_shared<RepositoryNameSet>();
+}
+
+void
+GemcutterRepository::populate_sets() const
+{
+}
+
+HookResult
+GemcutterRepository::perform_hook(const Hook &, const std::shared_ptr<OutputManager> &)
+{
+    return make_named_values<HookResult>(n::max_exit_status() = 0, n::output() = "");
+}
+
+const std::shared_ptr<const MetadataValueKey<std::string> >
+GemcutterRepository::accept_keywords_key() const
+{
+    return make_null_shared_ptr();
+}
+
+const std::shared_ptr<const MetadataValueKey<std::string> >
+GemcutterRepository::sync_host_key() const
+{
+    return make_null_shared_ptr();
+}
+
+template class Pimp<gemcutter_repository::GemcutterRepository>;
+
diff --git a/paludis/repositories/gemcutter/gemcutter_repository.hh b/paludis/repositories/gemcutter/gemcutter_repository.hh
new file mode 100644
index 000000000..ffecd7e66
--- /dev/null
+++ b/paludis/repositories/gemcutter/gemcutter_repository.hh
@@ -0,0 +1,127 @@
+/* vim: set sw=4 sts=4 et foldmethod=syntax : */
+
+/*
+ * Copyright (c) 2010 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
+ * Public License version 2, as published by the Free Software Foundation.
+ *
+ * Paludis is distributed in the hope that it will be useful, but WITHOUT ANY
+ * WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS
+ * FOR A PARTICULAR PURPOSE.  See the GNU General Public License for more
+ * details.
+ *
+ * You should have received a copy of the GNU General Public License along with
+ * this program; if not, write to the Free Software Foundation, Inc., 59 Temple
+ * Place, Suite 330, Boston, MA  02111-1307  USA
+ */
+
+#ifndef PALUDIS_GUARD_PALUDIS_REPOSITORIES_GEMCUTTER_GEMCUTTER_REPOSITORY_HH
+#define PALUDIS_GUARD_PALUDIS_REPOSITORIES_GEMCUTTER_GEMCUTTER_REPOSITORY_HH 1
+
+#include <paludis/repositories/gemcutter/gemcutter_repository-fwd.hh>
+#include <paludis/repository.hh>
+#include <paludis/util/pimp.hh>
+#include <paludis/util/attributes.hh>
+#include <paludis/util/fs_path.hh>
+
+namespace paludis
+{
+    namespace n
+    {
+        typedef Name<struct environment_name> environment;
+        typedef Name<struct location_name> location;
+        typedef Name<struct name_name> name;
+    }
+
+    namespace gemcutter_repository
+    {
+        class PALUDIS_VISIBLE GemcutterRepositoryConfigurationError :
+            public ConfigurationError
+        {
+            public:
+                GemcutterRepositoryConfigurationError(const std::string &) throw ();
+        };
+
+        struct GemcutterRepositoryParams
+        {
+            NamedValue<n::environment, Environment *> environment;
+            NamedValue<n::location, FSPath> location;
+            NamedValue<n::name, RepositoryName> name;
+        };
+
+        class PALUDIS_VISIBLE GemcutterRepository :
+            private Pimp<GemcutterRepository>,
+            public Repository,
+            public std::enable_shared_from_this<GemcutterRepository>
+        {
+            private:
+                Pimp<GemcutterRepository>::ImpPtr & _imp;
+
+                void _add_metadata_keys();
+
+            protected:
+                virtual void need_keys_added() const;
+
+            public:
+                GemcutterRepository(const GemcutterRepositoryParams &);
+                ~GemcutterRepository();
+
+                virtual bool can_be_favourite_repository() const;
+
+                virtual const bool is_unimportant() const;
+
+                virtual const std::shared_ptr<const MetadataValueKey<std::string> > format_key() const;
+                virtual const std::shared_ptr<const MetadataValueKey<FSPath> > location_key() const;
+                virtual const std::shared_ptr<const MetadataValueKey<FSPath> > installed_root_key() const;
+                virtual const std::shared_ptr<const MetadataValueKey<std::string> > accept_keywords_key() const;
+                virtual const std::shared_ptr<const MetadataValueKey<std::string> > sync_host_key() const;
+
+                virtual bool has_category_named(const CategoryNamePart & c) const;
+                virtual bool has_package_named(const QualifiedPackageName & q) const;
+                virtual std::shared_ptr<const CategoryNamePartSet> category_names() const;
+                virtual std::shared_ptr<const CategoryNamePartSet> unimportant_category_names() const;
+                virtual std::shared_ptr<const CategoryNamePartSet> category_names_containing_package(const PackageNamePart & p) const;
+                virtual std::shared_ptr<const QualifiedPackageNameSet> package_names(const CategoryNamePart & c) const;
+                virtual std::shared_ptr<const PackageIDSequence> package_ids(const QualifiedPackageName & p) const;
+
+                virtual bool some_ids_might_support_action(const SupportsActionTestBase &) const;
+                virtual bool some_ids_might_not_be_masked() const;
+                virtual void invalidate();
+                virtual void invalidate_masks();
+
+                virtual bool sync(const std::shared_ptr<OutputManager> &) const;
+
+                ///\name RepositoryFactory functions
+                ///\{
+
+                static RepositoryName repository_factory_name(
+                        const Environment * const env,
+                        const std::function<std::string (const std::string &)> &);
+
+                static std::shared_ptr<Repository> repository_factory_create(
+                        Environment * const env,
+                        const std::function<std::string (const std::string &)> &);
+
+                static std::shared_ptr<const RepositoryNameSet> repository_factory_dependencies(
+                        const Environment * const env,
+                        const std::function<std::string (const std::string &)> &);
+
+                ///\}
+
+                ///\name Set methods
+                ///\{
+
+                virtual void populate_sets() const;
+
+                ///\}
+
+                virtual HookResult perform_hook(const Hook & hook, const std::shared_ptr<OutputManager> &);
+            };
+    }
+
+    extern template class Pimp<gemcutter_repository::GemcutterRepository>;
+}
+
+#endif
diff --git a/paludis/repositories/gemcutter/gemcutter_repository_store.cc b/paludis/repositories/gemcutter/gemcutter_repository_store.cc
new file mode 100644
index 000000000..4a54282af
--- /dev/null
+++ b/paludis/repositories/gemcutter/gemcutter_repository_store.cc
@@ -0,0 +1,195 @@
+/* vim: set sw=4 sts=4 et foldmethod=syntax : */
+
+/*
+ * Copyright (c) 2010 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
+ * Public License version 2, as published by the Free Software Foundation.
+ *
+ * Paludis is distributed in the hope that it will be useful, but WITHOUT ANY
+ * WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS
+ * FOR A PARTICULAR PURPOSE.  See the GNU General Public License for more
+ * details.
+ *
+ * You should have received a copy of the GNU General Public License along with
+ * this program; if not, write to the Free Software Foundation, Inc., 59 Temple
+ * Place, Suite 330, Boston, MA  02111-1307  USA
+ */
+
+#include <paludis/repositories/gemcutter/gemcutter_repository_store.hh>
+#include <paludis/repositories/gemcutter/gemcutter_repository.hh>
+#include <paludis/repositories/gemcutter/gemcutter_id.hh>
+#include <paludis/repositories/gemcutter/json_things_handle.hh>
+#include <paludis/util/pimp-impl.hh>
+#include <paludis/util/stringify.hh>
+#include <paludis/util/set.hh>
+#include <paludis/util/sequence.hh>
+#include <paludis/util/hashes.hh>
+#include <paludis/util/is_file_with_extension.hh>
+#include <paludis/util/log.hh>
+#include <paludis/util/make_named_values.hh>
+#include <paludis/util/fs_stat.hh>
+#include <paludis/name.hh>
+#include <paludis/version_spec.hh>
+#include <paludis/literal_metadata_key.hh>
+#include <paludis/environment.hh>
+#include <paludis/package_database.hh>
+#include <functional>
+#include <unordered_map>
+#include <algorithm>
+#include <set>
+
+using namespace paludis;
+using namespace paludis::gemcutter_repository;
+
+typedef std::unordered_map<CategoryNamePart,
+        std::shared_ptr<QualifiedPackageNameSet>,
+        Hash<CategoryNamePart> > PackageNames;
+
+typedef std::unordered_map<QualifiedPackageName,
+        std::shared_ptr<PackageIDSequence>,
+        Hash<QualifiedPackageName> > IDs;
+
+namespace paludis
+{
+    template <>
+    struct Imp<GemcutterRepositoryStore>
+    {
+        const Environment * const env;
+        const GemcutterRepository * const repo;
+        const FSPath location;
+        std::shared_ptr<CategoryNamePartSet> categories;
+        PackageNames package_names;
+        IDs ids;
+
+        Imp(const Environment * const e, const GemcutterRepository * const r, const FSPath & l) :
+            env(e),
+            repo(r),
+            location(l),
+            categories(std::make_shared<CategoryNamePartSet>())
+        {
+        }
+    };
+}
+
+GemcutterRepositoryStore::GemcutterRepositoryStore(
+        const Environment * const env,
+        const GemcutterRepository * const repo,
+        const FSPath & location) :
+    Pimp<GemcutterRepositoryStore>(env, repo, location)
+{
+    _populate();
+}
+
+GemcutterRepositoryStore::~GemcutterRepositoryStore()
+{
+}
+
+void
+GemcutterRepositoryStore::_populate()
+{
+    Context context("When populating ::" + stringify(_imp->repo->name()) + ":");
+
+    FSPath all_gems(_imp->location / "all-gems.json");
+    if (! all_gems.stat().exists())
+    {
+        Log::get_instance()->message("gemcutter_repository.no_all_gems_file", ll_warning, lc_context)
+            << "File '" << all_gems << "' does not exist, and it should, unless you have just created "
+            << "the ::" << stringify(_imp->repo->name()) << " repository and not yet synced it";
+        return;
+    }
+
+    try
+    {
+        JSONThingsHandle::get_instance()->parse_all_gems(
+                all_gems,
+                std::bind(&GemcutterRepositoryStore::_populate_one, this, std::placeholders::_1));
+    }
+    catch (const Exception & e)
+    {
+        Log::get_instance()->message("gemcutter_repository.not_available", ll_warning, lc_context)
+            << "Not loading '" << all_gems << "' for ::" << stringify(_imp->repo->name()) << " due to "
+            << "exception '" << e.message() << "' (" << e.what() << ")";
+
+        _imp->categories->clear();
+        _imp->package_names.clear();
+        _imp->ids.clear();
+
+        return;
+    }
+}
+
+void
+GemcutterRepositoryStore::_populate_one(const GemJSONInfo & info)
+{
+    Context context("When populating ::" + stringify(_imp->repo->name()) + " " +
+            stringify(info.name()) + " " + stringify(info.version()) + ":");
+
+    const std::shared_ptr<GemcutterID> id(std::make_shared<GemcutterID>(make_named_values<GemcutterIDParams>(
+                    n::environment() = _imp->env,
+                    n::info() = info,
+                    n::repository() = _imp->repo
+                    )));
+
+    _imp->categories->insert(id->name().category());
+
+    PackageNames::iterator p(_imp->package_names.find(id->name().category()));
+    if (_imp->package_names.end() == p)
+        p = _imp->package_names.insert(std::make_pair(id->name().category(),
+                    std::make_shared<QualifiedPackageNameSet>())).first;
+    p->second->insert(id->name());
+
+    IDs::iterator i(_imp->ids.find(id->name()));
+    if (_imp->ids.end() == i)
+        i = _imp->ids.insert(std::make_pair(id->name(), std::make_shared<PackageIDSequence>())).first;
+    i->second->push_back(id);
+}
+
+bool
+GemcutterRepositoryStore::has_category_named(const CategoryNamePart & c) const
+{
+    return _imp->categories->end() != _imp->categories->find(c);
+}
+
+bool
+GemcutterRepositoryStore::has_package_named(const QualifiedPackageName & q) const
+{
+    return _imp->ids.end() != _imp->ids.find(q);
+}
+
+std::shared_ptr<const CategoryNamePartSet>
+GemcutterRepositoryStore::category_names() const
+{
+    return _imp->categories;
+}
+
+std::shared_ptr<const CategoryNamePartSet>
+GemcutterRepositoryStore::unimportant_category_names() const
+{
+    std::shared_ptr<CategoryNamePartSet> result(std::make_shared<CategoryNamePartSet>());
+    return result;
+}
+
+std::shared_ptr<const QualifiedPackageNameSet>
+GemcutterRepositoryStore::package_names(const CategoryNamePart & c) const
+{
+    auto p(_imp->package_names.find(c));
+    if (_imp->package_names.end() == p)
+        return std::make_shared<QualifiedPackageNameSet>();
+    else
+        return p->second;
+}
+
+std::shared_ptr<const PackageIDSequence>
+GemcutterRepositoryStore::package_ids(const QualifiedPackageName & p) const
+{
+    auto i(_imp->ids.find(p));
+    if (_imp->ids.end() == i)
+        return std::make_shared<PackageIDSequence>();
+    else
+        return i->second;
+}
+
+template class Pimp<gemcutter_repository::GemcutterRepositoryStore>;
+
diff --git a/paludis/repositories/gemcutter/gemcutter_repository_store.hh b/paludis/repositories/gemcutter/gemcutter_repository_store.hh
new file mode 100644
index 000000000..c175ce8fd
--- /dev/null
+++ b/paludis/repositories/gemcutter/gemcutter_repository_store.hh
@@ -0,0 +1,75 @@
+/* vim: set sw=4 sts=4 et foldmethod=syntax : */
+
+/*
+ * Copyright (c) 2010 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
+ * Public License version 2, as published by the Free Software Foundation.
+ *
+ * Paludis is distributed in the hope that it will be useful, but WITHOUT ANY
+ * WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS
+ * FOR A PARTICULAR PURPOSE.  See the GNU General Public License for more
+ * details.
+ *
+ * You should have received a copy of the GNU General Public License along with
+ * this program; if not, write to the Free Software Foundation, Inc., 59 Temple
+ * Place, Suite 330, Boston, MA  02111-1307  USA
+ */
+
+#ifndef PALUDIS_GUARD_PALUDIS_REPOSITORIES_GEMCUTTER_GEMCUTTER_REPOSITORY_STORE_HH
+#define PALUDIS_GUARD_PALUDIS_REPOSITORIES_GEMCUTTER_GEMCUTTER_REPOSITORY_STORE_HH 1
+
+#include <paludis/repositories/gemcutter/gemcutter_repository-fwd.hh>
+#include <paludis/repositories/gemcutter/json_things_handle-fwd.hh>
+#include <paludis/repositories/gemcutter/json_things.hh>
+#include <paludis/util/pimp.hh>
+#include <paludis/util/fs_path-fwd.hh>
+#include <paludis/name-fwd.hh>
+#include <paludis/package_id-fwd.hh>
+#include <paludis/environment-fwd.hh>
+#include <memory>
+
+namespace paludis
+{
+    namespace gemcutter_repository
+    {
+        class PALUDIS_VISIBLE GemcutterRepositoryStore :
+            private Pimp<GemcutterRepositoryStore>
+        {
+            private:
+                void _populate();
+                void _populate_one(const GemJSONInfo &);
+
+            public:
+                GemcutterRepositoryStore(
+                        const Environment * const,
+                        const GemcutterRepository * const,
+                        const FSPath &);
+
+                ~GemcutterRepositoryStore();
+
+                bool has_category_named(const CategoryNamePart &) const
+                    PALUDIS_ATTRIBUTE((warn_unused_result));
+
+                bool has_package_named(const QualifiedPackageName & q) const
+                    PALUDIS_ATTRIBUTE((warn_unused_result));
+
+                std::shared_ptr<const CategoryNamePartSet> category_names() const
+                    PALUDIS_ATTRIBUTE((warn_unused_result));
+
+                std::shared_ptr<const CategoryNamePartSet> unimportant_category_names() const
+                    PALUDIS_ATTRIBUTE((warn_unused_result));
+
+                std::shared_ptr<const QualifiedPackageNameSet> package_names(
+                        const CategoryNamePart & c) const PALUDIS_ATTRIBUTE((warn_unused_result));
+
+                std::shared_ptr<const PackageIDSequence> package_ids(
+                        const QualifiedPackageName & p) const PALUDIS_ATTRIBUTE((warn_unused_result));
+        };
+    }
+
+    extern template class Pimp<gemcutter_repository::GemcutterRepositoryStore>;
+}
+
+#endif
diff --git a/paludis/repositories/gemcutter/json_common-fwd.hh b/paludis/repositories/gemcutter/json_common-fwd.hh
new file mode 100644
index 000000000..ab2ae0414
--- /dev/null
+++ b/paludis/repositories/gemcutter/json_common-fwd.hh
@@ -0,0 +1,36 @@
+/* vim: set sw=4 sts=4 et foldmethod=syntax : */
+
+/*
+ * Copyright (c) 2010 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
+ * Public License version 2, as published by the Free Software Foundation.
+ *
+ * Paludis is distributed in the hope that it will be useful, but WITHOUT ANY
+ * WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS
+ * FOR A PARTICULAR PURPOSE.  See the GNU General Public License for more
+ * details.
+ *
+ * You should have received a copy of the GNU General Public License along with
+ * this program; if not, write to the Free Software Foundation, Inc., 59 Temple
+ * Place, Suite 330, Boston, MA  02111-1307  USA
+ */
+
+#ifndef PALUDIS_GUARD_PALUDIS_REPOSITORIES_GEMCUTTER_JSON_COMMON_FWD_HH
+#define PALUDIS_GUARD_PALUDIS_REPOSITORIES_GEMCUTTER_JSON_COMMON_FWD_HH 1
+
+#include <functional>
+
+namespace paludis
+{
+    namespace gemcutter_repository
+    {
+        class JSONError;
+        class GemJSONInfo;
+
+        typedef std::function<void (const GemJSONInfo &)> ParsedOneGemCallback;
+    }
+}
+
+#endif
diff --git a/paludis/repositories/gemcutter/json_common.cc b/paludis/repositories/gemcutter/json_common.cc
new file mode 100644
index 000000000..35b4d1e41
--- /dev/null
+++ b/paludis/repositories/gemcutter/json_common.cc
@@ -0,0 +1,29 @@
+/* vim: set sw=4 sts=4 et foldmethod=syntax : */
+
+/*
+ * Copyright (c) 2010 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
+ * Public License version 2, as published by the Free Software Foundation.
+ *
+ * Paludis is distributed in the hope that it will be useful, but WITHOUT ANY
+ * WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS
+ * FOR A PARTICULAR PURPOSE.  See the GNU General Public License for more
+ * details.
+ *
+ * You should have received a copy of the GNU General Public License along with
+ * this program; if not, write to the Free Software Foundation, Inc., 59 Temple
+ * Place, Suite 330, Boston, MA  02111-1307  USA
+ */
+
+#include <paludis/repositories/gemcutter/json_common.hh>
+
+using namespace paludis;
+using namespace paludis::gemcutter_repository;
+
+JSONError::JSONError(const std::string & s) throw () :
+    Exception(s)
+{
+}
+
diff --git a/paludis/repositories/gemcutter/json_common.hh b/paludis/repositories/gemcutter/json_common.hh
new file mode 100644
index 000000000..196a4e055
--- /dev/null
+++ b/paludis/repositories/gemcutter/json_common.hh
@@ -0,0 +1,52 @@
+/* vim: set sw=4 sts=4 et foldmethod=syntax : */
+
+/*
+ * Copyright (c) 2010 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
+ * Public License version 2, as published by the Free Software Foundation.
+ *
+ * Paludis is distributed in the hope that it will be useful, but WITHOUT ANY
+ * WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS
+ * FOR A PARTICULAR PURPOSE.  See the GNU General Public License for more
+ * details.
+ *
+ * You should have received a copy of the GNU General Public License along with
+ * this program; if not, write to the Free Software Foundation, Inc., 59 Temple
+ * Place, Suite 330, Boston, MA  02111-1307  USA
+ */
+
+#ifndef PALUDIS_GUARD_PALUDIS_REPOSITORIES_GEMCUTTER_JSON_COMMON_HH
+#define PALUDIS_GUARD_PALUDIS_REPOSITORIES_GEMCUTTER_JSON_COMMON_HH 1
+
+#include <paludis/repositories/gemcutter/json_common-fwd.hh>
+#include <paludis/util/exception.hh>
+#include <paludis/util/named_value.hh>
+
+namespace paludis
+{
+    namespace n
+    {
+        typedef Name<struct name_name> name;
+        typedef Name<struct version_name> version;
+    }
+
+    namespace gemcutter_repository
+    {
+        struct GemJSONInfo
+        {
+            NamedValue<n::name, std::string> name;
+            NamedValue<n::version, std::string> version;
+        };
+
+        class PALUDIS_VISIBLE JSONError :
+            public Exception
+        {
+            public:
+                JSONError(const std::string &) throw ();
+        };
+    }
+}
+
+#endif
diff --git a/paludis/repositories/gemcutter/json_things.cc b/paludis/repositories/gemcutter/json_things.cc
new file mode 100644
index 000000000..b525dab86
--- /dev/null
+++ b/paludis/repositories/gemcutter/json_things.cc
@@ -0,0 +1,74 @@
+/* vim: set sw=4 sts=4 et foldmethod=syntax : */
+
+/*
+ * Copyright (c) 2010 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
+ * Public License version 2, as published by the Free Software Foundation.
+ *
+ * Paludis is distributed in the hope that it will be useful, but WITHOUT ANY
+ * WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS
+ * FOR A PARTICULAR PURPOSE.  See the GNU General Public License for more
+ * details.
+ *
+ * You should have received a copy of the GNU General Public License along with
+ * this program; if not, write to the Free Software Foundation, Inc., 59 Temple
+ * Place, Suite 330, Boston, MA  02111-1307  USA
+ */
+
+#include <paludis/repositories/gemcutter/json_things.hh>
+#include <paludis/repositories/gemcutter/json_common.hh>
+#include <paludis/util/fs_path.hh>
+#include <paludis/util/make_named_values.hh>
+#include <paludis/util/stringify.hh>
+
+#include <jansson.h>
+
+using namespace paludis;
+using namespace paludis::gemcutter_repository;
+
+extern "C"
+void
+gemcutter_json_things_parse_all_gems(
+        const FSPath & path,
+        const ParsedOneGemCallback & parsed_one_gem)
+{
+    json_error_t error;
+    json_t * root(json_load_file(stringify(path).c_str(), &error));
+
+    if (! root)
+        throw JSONError("Couldn't load '" + stringify(path) + "': jansson said: " + error.text);
+
+    if (! json_is_array(root))
+        throw JSONError("Root is not an array");
+
+    for (int i(0), i_end(json_array_size(root)) ;
+            i != i_end ; ++i)
+    {
+        std::string name, version;
+
+        json_t * entry(json_array_get(root, i));
+        if ((! entry) || (! json_is_object(entry)))
+            throw JSONError("Entry is not an object");
+
+        json_t * name_id(json_object_get(entry, "name"));
+        if ((! name_id) || (! json_is_string(name_id)))
+            throw JSONError("Entry name is not a string");
+        name = std::string(json_string_value(name_id));
+
+        json_t * version_id(json_object_get(entry, "version"));
+        if ((! version_id) || (! json_is_string(version_id)))
+            throw JSONError("Entry version is not a string");
+        version = std::string(json_string_value(version_id));
+
+        GemJSONInfo info(make_named_values<GemJSONInfo>(
+                    n::name() = name,
+                    n::version() = version
+                    ));
+        parsed_one_gem(info);
+    }
+
+    json_decref(root);
+}
+
diff --git a/paludis/repositories/gemcutter/json_things.hh b/paludis/repositories/gemcutter/json_things.hh
new file mode 100644
index 000000000..20c4f68f9
--- /dev/null
+++ b/paludis/repositories/gemcutter/json_things.hh
@@ -0,0 +1,34 @@
+/* vim: set sw=4 sts=4 et foldmethod=syntax : */
+
+/*
+ * Copyright (c) 2010 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
+ * Public License version 2, as published by the Free Software Foundation.
+ *
+ * Paludis is distributed in the hope that it will be useful, but WITHOUT ANY
+ * WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS
+ * FOR A PARTICULAR PURPOSE.  See the GNU General Public License for more
+ * details.
+ *
+ * You should have received a copy of the GNU General Public License along with
+ * this program; if not, write to the Free Software Foundation, Inc., 59 Temple
+ * Place, Suite 330, Boston, MA  02111-1307  USA
+ */
+
+#ifndef PALUDIS_GUARD_PALUDIS_REPOSITORIES_GEMCUTTER_JSON_THINGS_HH
+#define PALUDIS_GUARD_PALUDIS_REPOSITORIES_GEMCUTTER_JSON_THINGS_HH 1
+
+#include <paludis/repositories/gemcutter/json_common-fwd.hh>
+#include <paludis/util/attributes.hh>
+#include <paludis/util/fs_path-fwd.hh>
+#include <paludis/util/named_value.hh>
+#include <paludis/util/exception.hh>
+#include <functional>
+
+extern "C" void gemcutter_json_things_parse_all_gems(
+        const paludis::FSPath &,
+        const paludis::gemcutter_repository::ParsedOneGemCallback &) PALUDIS_VISIBLE;
+
+#endif
diff --git a/paludis/repositories/gemcutter/json_things_handle-fwd.hh b/paludis/repositories/gemcutter/json_things_handle-fwd.hh
new file mode 100644
index 000000000..671fd4c47
--- /dev/null
+++ b/paludis/repositories/gemcutter/json_things_handle-fwd.hh
@@ -0,0 +1,31 @@
+/* vim: set sw=4 sts=4 et foldmethod=syntax : */
+
+/*
+ * Copyright (c) 2010 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
+ * Public License version 2, as published by the Free Software Foundation.
+ *
+ * Paludis is distributed in the hope that it will be useful, but WITHOUT ANY
+ * WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS
+ * FOR A PARTICULAR PURPOSE.  See the GNU General Public License for more
+ * details.
+ *
+ * You should have received a copy of the GNU General Public License along with
+ * this program; if not, write to the Free Software Foundation, Inc., 59 Temple
+ * Place, Suite 330, Boston, MA  02111-1307  USA
+ */
+
+#ifndef PALUDIS_GUARD_PALUDIS_REPOSITORIES_GEMCUTTER_JSON_THINGS_HANDLE_FWD_HH
+#define PALUDIS_GUARD_PALUDIS_REPOSITORIES_GEMCUTTER_JSON_THINGS_HANDLE_FWD_HH 1
+
+namespace paludis
+{
+    namespace gemcutter_repository
+    {
+        struct JSONThingsHandle;
+    }
+}
+
+#endif
diff --git a/paludis/repositories/gemcutter/json_things_handle.cc b/paludis/repositories/gemcutter/json_things_handle.cc
new file mode 100644
index 000000000..f6d48bd10
--- /dev/null
+++ b/paludis/repositories/gemcutter/json_things_handle.cc
@@ -0,0 +1,63 @@
+/* vim: set sw=4 sts=4 et foldmethod=syntax : */
+
+/*
+ * Copyright (c) 2010 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
+ * Public License version 2, as published by the Free Software Foundation.
+ *
+ * Paludis is distributed in the hope that it will be useful, but WITHOUT ANY
+ * WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS
+ * FOR A PARTICULAR PURPOSE.  See the GNU General Public License for more
+ * details.
+ *
+ * You should have received a copy of the GNU General Public License along with
+ * this program; if not, write to the Free Software Foundation, Inc., 59 Temple
+ * Place, Suite 330, Boston, MA  02111-1307  USA
+ */
+
+#include <paludis/repositories/gemcutter/json_things_handle.hh>
+#include <paludis/util/singleton-impl.hh>
+#include <paludis/util/exception.hh>
+
+#include <paludis/about.hh>
+
+#include <string.h>
+#include <dlfcn.h>
+#include <stdint.h>
+
+#include "config.h"
+
+#define STUPID_CAST(type, val) reinterpret_cast<type>(reinterpret_cast<uintptr_t>(val))
+
+using namespace paludis;
+using namespace paludis::gemcutter_repository;
+
+JSONThingsHandle::JSONThingsHandle() :
+    handle(0),
+    parse_all_gems_function(0)
+{
+    handle = ::dlopen(("libpaludisgemcutterrepositoryjsonthings_" + stringify(PALUDIS_PC_SLOT) + ".so").c_str(), RTLD_NOW | RTLD_GLOBAL);
+    if (! handle)
+        throw NotAvailableError("JSON not available because dlopen said " + stringify(::dlerror()));
+
+    parse_all_gems_function = STUPID_CAST(ParseAllGemsFunction, ::dlsym(handle, "gemcutter_json_things_parse_all_gems"));
+    if (! parse_all_gems_function)
+        throw NotAvailableError("JSON not available because dlsym said " + stringify(::dlerror()));
+}
+
+JSONThingsHandle::~JSONThingsHandle()
+{
+    if (handle)
+        ::dlclose(handle);
+}
+
+void
+JSONThingsHandle::parse_all_gems(const FSPath & p, const ParsedOneGemCallback & c) const
+{
+    parse_all_gems_function(p, c);
+}
+
+template class Singleton<JSONThingsHandle>;
+
diff --git a/paludis/repositories/gemcutter/json_things_handle.hh b/paludis/repositories/gemcutter/json_things_handle.hh
new file mode 100644
index 000000000..9a45b57fa
--- /dev/null
+++ b/paludis/repositories/gemcutter/json_things_handle.hh
@@ -0,0 +1,56 @@
+/* vim: set sw=4 sts=4 et foldmethod=syntax : */
+
+/*
+ * Copyright (c) 2010 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
+ * Public License version 2, as published by the Free Software Foundation.
+ *
+ * Paludis is distributed in the hope that it will be useful, but WITHOUT ANY
+ * WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS
+ * FOR A PARTICULAR PURPOSE.  See the GNU General Public License for more
+ * details.
+ *
+ * You should have received a copy of the GNU General Public License along with
+ * this program; if not, write to the Free Software Foundation, Inc., 59 Temple
+ * Place, Suite 330, Boston, MA  02111-1307  USA
+ */
+
+#ifndef PALUDIS_GUARD_PALUDIS_REPOSITORIES_GEMCUTTER_JSON_THINGS_HANDLE_HH
+#define PALUDIS_GUARD_PALUDIS_REPOSITORIES_GEMCUTTER_JSON_THINGS_HANDLE_HH 1
+
+#include <paludis/repositories/gemcutter/json_things_handle-fwd.hh>
+#include <paludis/repositories/gemcutter/json_things.hh>
+#include <paludis/util/singleton.hh>
+#include <paludis/util/named_value.hh>
+#include <paludis/util/fs_path-fwd.hh>
+#include <string>
+
+namespace paludis
+{
+    namespace gemcutter_repository
+    {
+        class JSONThingsHandle :
+            public Singleton<JSONThingsHandle>
+        {
+            friend class Singleton<JSONThingsHandle>;
+
+            private:
+                void * handle;
+
+                typedef void (* ParseAllGemsFunction)(const FSPath &, const ParsedOneGemCallback &);
+                ParseAllGemsFunction parse_all_gems_function;
+
+                JSONThingsHandle();
+                ~JSONThingsHandle();
+
+            public:
+                void parse_all_gems(const FSPath &, const ParsedOneGemCallback &) const;
+        };
+    }
+
+    extern template class Singleton<gemcutter_repository::JSONThingsHandle>;
+}
+
+#endif
diff --git a/paludis/repositories/gemcutter/registration.cc b/paludis/repositories/gemcutter/registration.cc
new file mode 100644
index 000000000..597300215
--- /dev/null
+++ b/paludis/repositories/gemcutter/registration.cc
@@ -0,0 +1,62 @@
+/* vim: set sw=4 sts=4 et foldmethod=syntax : */
+
+/*
+ * Copyright (c) 2010 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
+ * Public License version 2, as published by the Free Software Foundation.
+ *
+ * Paludis is distributed in the hope that it will be useful, but WITHOUT ANY
+ * WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS
+ * FOR A PARTICULAR PURPOSE.  See the GNU General Public License for more
+ * details.
+ *
+ * You should have received a copy of the GNU General Public License along with
+ * this program; if not, write to the Free Software Foundation, Inc., 59 Temple
+ * Place, Suite 330, Boston, MA  02111-1307  USA
+ */
+
+#include <paludis/repository_factory.hh>
+#include <paludis/repositories/gemcutter/gemcutter_repository.hh>
+#include <paludis/util/set.hh>
+#include <paludis/util/destringify.hh>
+#include "config.h"
+
+using namespace paludis;
+using namespace paludis::gemcutter_repository;
+
+namespace
+{
+    int generic_importance(const Environment * const, const std::function<std::string (const std::string &)> & f)
+    {
+        if (! f("importance").empty())
+            return destringify<int>(f("importance"));
+        else
+            return 1;
+    }
+}
+
+namespace paludis
+{
+    namespace repository_groups
+    {
+        REPOSITORY_GROUPS_DECLS;
+    }
+
+    template <>
+    void register_repositories<repository_groups::gemcutter>(const repository_groups::gemcutter * const,
+            RepositoryFactory * const factory)
+    {
+        std::shared_ptr<Set<std::string> > repository_formats(std::make_shared<Set<std::string>>());
+        repository_formats->insert("gemcutter");
+
+        factory->add_repository_format(repository_formats,
+                &GemcutterRepository::repository_factory_name,
+                &generic_importance,
+                &GemcutterRepository::repository_factory_create,
+                &GemcutterRepository::repository_factory_dependencies
+                );
+    }
+}
+