First draft of legend generator.

arangod/Wal/Slot.h

@@ -29,6 +29,7 @@
 #define TRIAGENS_WAL_LOG_SLOT_H 1
 
 #include "Basics/Common.h"
+#include "ShapedJson/Legends.h"
 #include "Wal/Logfile.h"
 
 extern "C" {

lib/Makefile.files

@@ -89,6 +89,7 @@ lib_libarango_a_SOURCES = \
 	lib/Rest/InitialiseRest.cpp \
 	lib/Rest/SslInterface.cpp \
 	lib/Rest/Version.cpp \
+	lib/ShapedJson/Legends.cpp \
 	lib/ShapedJson/json-shaper.cpp \
 	lib/ShapedJson/shape-accessor.cpp \
 	lib/ShapedJson/shaped-json.cpp \

lib/ShapedJson/Legends.cpp

@@ -0,0 +1,134 @@
+////////////////////////////////////////////////////////////////////////////////
+/// @brief legends for shaped JSON objects to make them self-contained
+///
+/// @file
+/// Code for legends.
+///
+/// DISCLAIMER
+///
+/// Copyright 2004-2014 triAGENS GmbH, Cologne, Germany
+///
+/// Licensed under the Apache License, Version 2.0 (the "License");
+/// you may not use this file except in compliance with the License.
+/// You may obtain a copy of the License at
+///
+///     http://www.apache.org/licenses/LICENSE-2.0
+///
+/// Unless required by applicable law or agreed to in writing, software
+/// distributed under the License is distributed on an "AS IS" BASIS,
+/// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+/// See the License for the specific language governing permissions and
+/// limitations under the License.
+///
+/// Copyright holder is triAGENS GmbH, Cologne, Germany
+///
+/// @author Max Neunhoeffer
+/// @author Copyright 2014-2014, triAGENS GmbH, Cologne, Germany
+////////////////////////////////////////////////////////////////////////////////
+
+#include "ShapedJson/Legends.h"
+
+using namespace std;
+using namespace triagens;
+using namespace triagens::basics;
+
+
+void JsonLegend::clear () {
+  _have_attribute.clear();
+  _attribs.clear();
+  _att_data.clear();
+  _have_shape.clear();
+  _shapes.clear();
+  _shape_data.clear();
+}
+
+bool JsonLegend::addAttributeId (TRI_shape_aid_t aid) {
+  unordered_set<TRI_shape_aid_t>::const_iterator it = _have_attribute.find(aid);
+  if (it != _have_attribute.end()) {
+    return true;
+  }
+
+  char const* p = _shaper->lookupAttributeId(_shaper, aid);
+  if (0 == p) {
+    return false;
+  }
+
+  _have_attribute.insert(aid);
+  size_t len = strlen(p);
+  _attribs.emplace_back(aid, _att_data.length());
+  _att_data.appendText(p, len+1);   // including the zero byte
+  return true;
+}
+
+bool JsonLegend::addShape (TRI_shape_sid_t sid, 
+                           char const* data, uint32_t len) {
+  // data can be 0, then no data is associated, note that if the shape
+  // contains an inhomogeneous list as one of its subobjects, then the
+  // shape legend could be incomplete, because the actual shapes of
+  // the subobject(s) are held only in the data and not in the shaper.
+
+  TRI_shape_t const* shape = 0;
+
+  // First the trivial cases:
+  if (sid < TRI_FirstCustomShapeIdShaper()) {
+    shape = TRI_LookupSidBasicShapeShaper(sid);
+  }
+  else {
+    unordered_set<TRI_shape_sid_t>::const_iterator it = _have_shape.find(sid);
+    if (it == _have_shape.end()) {
+      TRI_shape_t const* shape = _shaper->lookupShapeId(_shaper, sid);
+      if (0 == shape) {
+        return false;
+      }
+
+      _have_shape.insert(sid);
+      Shape sh(sid, _shape_data.length(), shape->_size);
+      _shapes.push_back(sh);
+      _shape_data.appendText( reinterpret_cast<char const*>(shape),
+                              shape->_size );
+    }
+  }
+
+  // Now we have to add all attribute IDs and all shapes used by this
+  // one recursively, note that the data of this object is in a
+  // consistent state, such that we can call ourselves recursively.
+  if (shape->_type == TRI_SHAPE_HOMOGENEOUS_SIZED_LIST) {
+    // Handle a homogeneous list with equal size entries:
+    // Subobjects have fixed size, so in particular no subobject can
+    // contain any inhomogeneous list as one of its subobjects.
+    // ...
+  }
+  else if (shape->_type == TRI_SHAPE_HOMOGENEOUS_LIST) {
+    // Handle a homogeneous list:
+    // Only one sid, but one of the subobjects could be an
+    // inhomogeneous list. We first scan the shape without data, if this
+    // goes well, there was no subshape containing an inhomogeneous
+    // list! Otherwise, we have to scan all entries of the list.
+    // ...
+  }
+  else if (shape->_type == TRI_SHAPE_LIST) {
+    // Handle an inhomogeneous list:
+    // We have to scan recursively all entries of the list since they
+    // contain sids in the data area.
+    // ...
+  }
+  else if (shape->_type == TRI_SHAPE_ARRAY) {
+    // Handle an array ...
+    // Distinguish between fixed size subobjects and variable size
+    // subobjects. The fixed ones cannot contain inhomogeneous lists.
+    // ...
+  }
+
+  return true;
+}
+
+size_t JsonLegend::getSize () {
+  // Add string pool size and shape pool size and add space for header
+  // and tables.
+  return 0;
+}
+
+void JsonLegend::dump (void* buf) {
+  // Dump the resulting legend to a given buffer.
+
+}

lib/ShapedJson/Legends.h

@@ -0,0 +1,119 @@
+////////////////////////////////////////////////////////////////////////////////
+/// @brief legends for shaped JSON objects to make them self-contained
+///
+/// @file
+/// Declaration for legends.
+///
+/// DISCLAIMER
+///
+/// Copyright 2004-2014 triAGENS GmbH, Cologne, Germany
+///
+/// Licensed under the Apache License, Version 2.0 (the "License");
+/// you may not use this file except in compliance with the License.
+/// You may obtain a copy of the License at
+///
+///     http://www.apache.org/licenses/LICENSE-2.0
+///
+/// Unless required by applicable law or agreed to in writing, software
+/// distributed under the License is distributed on an "AS IS" BASIS,
+/// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+/// See the License for the specific language governing permissions and
+/// limitations under the License.
+///
+/// Copyright holder is triAGENS GmbH, Cologne, Germany
+///
+/// @author Max Neunhoeffer
+/// @author Copyright 2014-2014, triAGENS GmbH, Cologne, Germany
+////////////////////////////////////////////////////////////////////////////////
+
+#ifndef TRIAGENS_SHAPED_JSON_LEGENDS_H
+#define TRIAGENS_SHAPED_JSON_LEGENDS_H 1
+
+#include "BasicsC/common.h"
+#include "Basics/Common.h"
+
+#include "BasicsC/structures.h"
+#include "Basics/StringBuffer.h"
+#include "ShapedJson/shaped-json.h"
+#include "ShapedJson/json-shaper.h"
+
+
+namespace triagens {
+  namespace basics {
+
+    class JsonLegend {
+
+      public:
+
+        JsonLegend (TRI_shaper_t* shaper) 
+          : _shaper(shaper), _att_data(TRI_UNKNOWN_MEM_ZONE),
+            _shape_data(TRI_UNKNOWN_MEM_ZONE) {
+        }
+
+        ~JsonLegend () {
+        };
+
+        void reset (TRI_shaper_t* shaper) {
+          clear();
+          _shaper = shaper;
+        }
+
+        void clear ();
+
+        bool addAttributeId (TRI_shape_aid_t aid);
+
+        bool addShape (TRI_shaped_json_t const* sh_json) {
+          return addShape(sh_json->_sid, sh_json->_data.data,
+                          sh_json->_data.length);
+        }
+
+        bool addShape (TRI_shape_sid_t sid, TRI_blob_t const* blob) {
+          return addShape(sid, blob->data, blob->length);
+        }
+
+        bool addShape (TRI_shape_sid_t sid, char const* data, uint32_t len);
+
+        size_t getSize ();
+
+        void dump (void* buf);
+
+      private:
+
+        TRI_shaper_t* _shaper;
+
+        struct AttributeId {
+          TRI_shape_aid_t aid;
+          TRI_shape_size_t offset;
+
+          AttributeId (TRI_shape_aid_t a, TRI_shape_size_t o)
+            : aid(a), offset(o) {}
+
+        };
+
+        struct Shape {
+          TRI_shape_sid_t sid;
+          TRI_shape_size_t offset;
+          TRI_shape_size_t size;
+
+          Shape (TRI_shape_sid_t sid, TRI_shape_size_t o, TRI_shape_size_t siz)
+            : sid(sid), offset(o), size(siz) {}
+
+        };
+
+        unordered_set<TRI_shape_aid_t> _have_attribute;
+        vector<AttributeId> _attribs;
+        StringBuffer _att_data;
+        unordered_set<TRI_shape_sid_t> _have_shape;
+        vector<Shape> _shapes;
+        StringBuffer _shape_data;
+    };
+
+  }
+}
+
+#endif
+
+// Local Variables:
+// mode: outline-minor
+// outline-regexp: "/// @brief\\|/// {@inheritDoc}\\|/// @addtogroup\\|/// @page\\|// --SECTION--\\|/// @\\}"
+// End: