Add Directory container and iterator (RIPD-968)

Builds/VisualStudio2013/RippleD.vcxproj

@@ -2299,6 +2299,8 @@
     </ClInclude>
     <None Include="..\..\src\ripple\ledger\detail\ReadViewFwdRange.ipp">
     </None>
+    <ClInclude Include="..\..\src\ripple\ledger\Directory.h">
+    </ClInclude>
     <ClCompile Include="..\..\src\ripple\ledger\impl\ApplyStateTable.cpp">
       <ExcludedFromBuild Condition="'$(Configuration)|$(Platform)'=='debug|x64'">True</ExcludedFromBuild>
       <ExcludedFromBuild Condition="'$(Configuration)|$(Platform)'=='release|x64'">True</ExcludedFromBuild>
@@ -2319,6 +2321,10 @@
       <ExcludedFromBuild Condition="'$(Configuration)|$(Platform)'=='debug|x64'">True</ExcludedFromBuild>
       <ExcludedFromBuild Condition="'$(Configuration)|$(Platform)'=='release|x64'">True</ExcludedFromBuild>
     </ClCompile>
+    <ClCompile Include="..\..\src\ripple\ledger\impl\Directory.cpp">
+      <ExcludedFromBuild Condition="'$(Configuration)|$(Platform)'=='debug|x64'">True</ExcludedFromBuild>
+      <ExcludedFromBuild Condition="'$(Configuration)|$(Platform)'=='release|x64'">True</ExcludedFromBuild>
+    </ClCompile>
     <ClCompile Include="..\..\src\ripple\ledger\impl\OpenView.cpp">
       <ExcludedFromBuild Condition="'$(Configuration)|$(Platform)'=='debug|x64'">True</ExcludedFromBuild>
       <ExcludedFromBuild Condition="'$(Configuration)|$(Platform)'=='release|x64'">True</ExcludedFromBuild>
@@ -2349,6 +2355,10 @@
     </ClInclude>
     <ClInclude Include="..\..\src\ripple\ledger\Sandbox.h">
     </ClInclude>
+    <ClCompile Include="..\..\src\ripple\ledger\tests\Directory_test.cpp">
+      <ExcludedFromBuild Condition="'$(Configuration)|$(Platform)'=='debug|x64'">True</ExcludedFromBuild>
+      <ExcludedFromBuild Condition="'$(Configuration)|$(Platform)'=='release|x64'">True</ExcludedFromBuild>
+    </ClCompile>
     <ClInclude Include="..\..\src\ripple\ledger\tests\PathSet.h">
     </ClInclude>
     <ClCompile Include="..\..\src\ripple\ledger\tests\PaymentSandbox_test.cpp">

Builds/VisualStudio2013/RippleD.vcxproj.filters

@@ -3036,6 +3036,9 @@
     <None Include="..\..\src\ripple\ledger\detail\ReadViewFwdRange.ipp">
       <Filter>ripple\ledger\detail</Filter>
     </None>
+    <ClInclude Include="..\..\src\ripple\ledger\Directory.h">
+      <Filter>ripple\ledger</Filter>
+    </ClInclude>
     <ClCompile Include="..\..\src\ripple\ledger\impl\ApplyStateTable.cpp">
       <Filter>ripple\ledger\impl</Filter>
     </ClCompile>
@@ -3051,6 +3054,9 @@
     <ClCompile Include="..\..\src\ripple\ledger\impl\CachingReadView.cpp">
       <Filter>ripple\ledger\impl</Filter>
     </ClCompile>
+    <ClCompile Include="..\..\src\ripple\ledger\impl\Directory.cpp">
+      <Filter>ripple\ledger\impl</Filter>
+    </ClCompile>
     <ClCompile Include="..\..\src\ripple\ledger\impl\OpenView.cpp">
       <Filter>ripple\ledger\impl</Filter>
     </ClCompile>
@@ -3081,6 +3087,9 @@
     <ClInclude Include="..\..\src\ripple\ledger\Sandbox.h">
       <Filter>ripple\ledger</Filter>
     </ClInclude>
+    <ClCompile Include="..\..\src\ripple\ledger\tests\Directory_test.cpp">
+      <Filter>ripple\ledger\tests</Filter>
+    </ClCompile>
     <ClInclude Include="..\..\src\ripple\ledger\tests\PathSet.h">
       <Filter>ripple\ledger\tests</Filter>
     </ClInclude>

src/ripple/ledger/Directory.h

@@ -0,0 +1,135 @@
+//------------------------------------------------------------------------------
+/*
+    This file is part of rippled: https://github.com/ripple/rippled
+    Copyright (c) 2012, 2015 Ripple Labs Inc.
+
+    Permission to use, copy, modify, and/or distribute this software for any
+    purpose  with  or without fee is hereby granted, provided that the above
+    copyright notice and this permission notice appear in all copies.
+
+    THE  SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
+    WITH  REGARD  TO  THIS  SOFTWARE  INCLUDING  ALL  IMPLIED  WARRANTIES  OF
+    MERCHANTABILITY  AND  FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
+    ANY  SPECIAL ,  DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
+    WHATSOEVER  RESULTING  FROM  LOSS  OF USE, DATA OR PROFITS, WHETHER IN AN
+    ACTION  OF  CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
+    OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
+*/
+//==============================================================================
+
+#ifndef RIPPLE_LEDGER_DIR_H_INCLUDED
+#define RIPPLE_LEDGER_DIR_H_INCLUDED
+
+#include <ripple/ledger/ReadView.h>
+#include <ripple/protocol/Indexes.h>
+
+namespace ripple {
+
+class Dir
+{
+private:
+    ReadView const* view_ = nullptr;
+    Keylet root_;
+
+    // memoization
+    std::shared_ptr<SLE const> sle_;
+    STVector256 const* indexes_ = nullptr;
+
+public:
+    class const_iterator;
+    using value_type = std::shared_ptr<SLE const>;
+
+    Dir(ReadView const&, Keylet const&);
+
+    const_iterator
+    begin() const;
+
+    const_iterator
+    end() const;
+
+    const_iterator
+    find(uint256 const& page_key, uint256 const& sle_key) const;
+};
+
+class Dir::const_iterator
+{
+public:
+    using value_type =
+        Dir::value_type;
+    using pointer =
+        value_type const*;
+    using reference =
+        value_type const&;
+    using difference_type =
+        std::ptrdiff_t;
+    using iterator_category =
+        std::forward_iterator_tag;
+
+    const_iterator() = default;
+
+    const_iterator&
+    operator=(const_iterator const& other);
+
+    bool
+    operator==(const_iterator const& other) const;
+
+    bool
+    operator!=(const_iterator const& other) const
+    {
+        return ! (*this == other);
+    }
+
+    reference
+    operator*() const;
+
+    pointer
+    operator->() const
+    {
+        return &**this;
+    }
+
+    const_iterator&
+    operator++();
+
+    const_iterator
+    operator++(int);
+
+    Keylet const&
+    page() const
+    {
+        return page_;
+    }
+
+    uint256
+    index() const
+    {
+        return index_;
+    }
+
+private:
+    friend class Dir;
+
+    const_iterator(ReadView const& view,
+        Keylet const& root,
+        Keylet const& page)
+    : view_(&view)
+    , root_(root)
+    , page_(page)
+    {
+    }
+
+    ReadView const* view_ = nullptr;
+    Keylet root_;
+    Keylet page_;
+    uint256 index_;
+    boost::optional<value_type> mutable cache_;
+
+    // memoization
+    std::shared_ptr<SLE const> sle_;
+    STVector256 const* indexes_ = nullptr;
+    std::vector<uint256>::const_iterator it_;
+};
+
+} // ripple
+
+#endif

src/ripple/ledger/impl/Directory.cpp

@@ -0,0 +1,177 @@
+//------------  ------------------------------------------------------------------
+/*
+    This file is part of rippled: https://github.com/ripple/rippled
+    Copyright (c) 2012, 2015 Ripple Labs Inc.
+
+    Permission to use, copy, modify, and/or distribute this software for any
+    purpose  with  or without fee is hereby granted, provided that the above
+    copyright notice and this permission notice appear in all copies.
+
+    THE  SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
+    WITH  REGARD  TO  THIS  SOFTWARE  INCLUDING  ALL  IMPLIED  WARRANTIES  OF
+    MERCHANTABILITY  AND  FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
+    ANY  SPECIAL ,  DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
+    WHATSOEVER  RESULTING  FROM  LOSS  OF USE, DATA OR PROFITS, WHETHER IN AN
+    ACTION  OF  CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
+    OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
+*/
+//==============================================================================
+
+#include <BeastConfig.h>
+#include <ripple/ledger/Directory.h>
+
+namespace ripple {
+
+using const_iterator = Dir::const_iterator;
+
+Dir::Dir(ReadView const& view,
+        Keylet const& key)
+    : view_(&view)
+    , root_(key)
+    , sle_(view_->read(root_))
+
+{
+    if (sle_ != nullptr)
+        indexes_ = &sle_->getFieldV256(sfIndexes);
+}
+
+auto
+Dir::begin() const ->
+    const_iterator
+{
+    auto it = const_iterator(*view_, root_, root_);
+    if (sle_ != nullptr)
+    {
+        it.sle_ = sle_;
+        if (! indexes_->empty())
+        {
+            it.indexes_ = indexes_;
+            it.it_ = std::begin(*indexes_);
+            it.index_ = *it.it_;
+        }
+    }
+
+    return it;
+}
+
+auto
+Dir::end() const  ->
+    const_iterator
+{
+    return const_iterator(*view_, root_, root_);
+}
+
+const_iterator
+Dir::find(uint256 const& page_key, uint256 const& sle_key) const
+{
+    if (sle_ == nullptr)
+        return end();
+
+    auto it = const_iterator(*view_, root_, keylet::page(page_key, 0));
+    if (root_.key == page_key)
+    {
+        it.sle_ = sle_;
+        it.indexes_ = indexes_;
+    }
+    else
+    {
+        it.sle_ = view_->read(it.page_);
+        if (it.sle_ == nullptr)
+            return end();
+        it.indexes_ = &it.sle_->getFieldV256(sfIndexes);
+    }
+
+    it.it_ = std::find(std::begin(*it.indexes_),
+        std::end(*it.indexes_), sle_key);
+    if (it.it_ == std::end(*it.indexes_))
+        return end();
+
+    it.index_ = *it.it_;
+    return it;
+}
+
+const_iterator&
+const_iterator::operator=(const_iterator const& other)
+{
+    if (this != &other)
+    {
+        view_ = other.view_;
+        root_ = other.root_;
+        page_ = other.page_;
+        index_ = other.index_;
+        cache_ = other.cache_;
+        sle_ = other.sle_;
+        indexes_ = other.indexes_;
+        it_ = other.it_;
+    }
+    return *this;
+}
+
+bool
+const_iterator::operator==(const_iterator const& other) const
+{
+    if (view_ == nullptr || other.view_ == nullptr)
+        return false;
+
+    assert(view_ == other.view_ && root_.key == other.root_.key);
+    return page_.key == other.page_.key && index_ == other.index_;
+}
+
+const_iterator::reference
+const_iterator::operator*() const
+{
+    assert(index_ != beast::zero);
+    if (! cache_)
+        cache_ = view_->read(keylet::child(index_));
+    return *cache_;
+}
+
+const_iterator&
+const_iterator::operator++()
+{
+    assert(index_ != beast::zero);
+    if (++it_ != std::end(*indexes_))
+    {
+        index_ = *it_;
+    }
+    else
+    {
+        auto const next =
+            sle_->getFieldU64(sfIndexNext);
+        if (next == 0)
+        {
+            page_.key = root_.key;
+            index_ = beast::zero;
+        }
+        else
+        {
+            page_ = keylet::page(root_, next);
+            sle_ = view_->read(page_);
+            assert(sle_);
+            indexes_ = &sle_->getFieldV256(sfIndexes);
+            if (indexes_->empty())
+            {
+                index_ = beast::zero;
+            }
+            else
+            {
+                it_ = std::begin(*indexes_);
+                index_ = *it_;
+            }
+        }
+    }
+
+    cache_ = boost::none;
+    return *this;
+}
+
+const_iterator
+const_iterator::operator++(int)
+{
+    assert(index_ != beast::zero);
+    const_iterator tmp(*this);
+    ++(*this);
+    return tmp;
+}
+
+} // ripple

src/ripple/ledger/tests/Directory_test.cpp

@@ -0,0 +1,83 @@
+//------------------------------------------------------------------------------
+/*
+    This file is part of rippled: https://github.com/ripple/rippled
+    Copyright (c) 2012, 2013 Ripple Labs Inc.
+    Permission to use, copy, modify, and/or distribute this software for any
+    purpose  with  or without fee is hereby granted, provided that the above
+    copyright notice and this permission notice appear in all copies.
+    THE  SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
+    WITH  REGARD  TO  THIS  SOFTWARE  INCLUDING  ALL  IMPLIED  WARRANTIES  OF
+    MERCHANTABILITY  AND  FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
+    ANY  SPECIAL ,  DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
+    WHATSOEVER  RESULTING  FROM  LOSS  OF USE, DATA OR PROFITS, WHETHER IN AN
+    ACTION  OF  CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
+    OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
+*/
+//==============================================================================
+
+#include <BeastConfig.h>
+#include <ripple/test/jtx.h>
+#include <ripple/ledger/Directory.h>
+
+namespace ripple {
+namespace test {
+
+struct Directory_test : public beast::unit_test::suite
+{
+    void testDirectory()
+    {
+        using namespace jtx;
+        Env env(*this);
+        auto gw = Account("gw");
+        auto USD = gw["USD"];
+
+        {
+            auto dir = Dir(*env.open(),
+                keylet::ownerDir(Account("alice")));
+            expect(std::begin(dir) == std::end(dir));
+            expect(std::end(dir) == dir.find(uint256(), uint256()));
+        }
+
+        env.fund(XRP(10000), "alice", "bob", gw);
+
+        auto i = 10;
+        for (; i <= 400; i += 10)
+            env(offer("alice", USD(i), XRP(10)));
+        env(offer("bob", USD(500), XRP(10)));
+
+        {
+            auto dir = Dir(*env.open(),
+                keylet::ownerDir(Account("bob")));
+            expect(std::begin(dir)->get()->
+                getFieldAmount(sfTakerPays) == USD(500));
+        }
+
+        auto dir = Dir(*env.open(),
+            keylet::ownerDir(Account("alice")));
+        i = 0;
+        for (auto const& e : dir)
+            expect(e->getFieldAmount(sfTakerPays) == USD(i += 10));
+
+        expect(std::begin(dir) != std::end(dir));
+        expect(std::end(dir) ==
+            dir.find(std::begin(dir).page().key,
+                uint256()));
+        expect(std::begin(dir) ==
+            dir.find(std::begin(dir).page().key,
+                std::begin(dir).index()));
+        auto entry = std::next(std::begin(dir), 32);
+        auto it = dir.find(entry.page().key, entry.index());
+        expect(it != std::end(dir));
+        expect((*it)->getFieldAmount(sfTakerPays) == USD(330));
+    }
+
+    void run() override
+    {
+        testDirectory();
+    }
+};
+
+BEAST_DEFINE_TESTSUITE(Directory,ledger,ripple);
+
+} // test
+} // ripple

src/ripple/unity/ledger.cpp

@@ -24,6 +24,7 @@
 #include <ripple/ledger/impl/ApplyViewImpl.cpp>
 #include <ripple/ledger/impl/CachedSLEs.cpp>
 #include <ripple/ledger/impl/CachingReadView.cpp>
+#include <ripple/ledger/impl/Directory.cpp>
 #include <ripple/ledger/impl/OpenView.cpp>
 #include <ripple/ledger/impl/PaymentSandbox.cpp>
 #include <ripple/ledger/impl/RawStateTable.cpp>
@@ -32,3 +33,4 @@
 
 #include <ripple/ledger/tests/PaymentSandbox_test.cpp>
 #include <ripple/ledger/tests/View_test.cpp>
+#include <ripple/ledger/tests/Directory_test.cpp>