Add lint script and fix cpplint errors

include/dgl/graph.h

-// DGL Graph interface
-#ifndef DGL_DGLGRAPH_H_
-#define DGL_DGLGRAPH_H_
+/*!
+ *  Copyright (c) 2018 by Contributors
+ * \file dgl/graph.h
+ * \brief DGL graph index class.
+ */
+#ifndef DGL_GRAPH_H_
+#define DGL_GRAPH_H_
 
-#include <stdint.h>
+#include <vector>
+#include <cstdint>
 #include "runtime/ndarray.h"
 
 namespace dgl {
@@ -17,7 +22,7 @@ class GraphOp;
 struct Subgraph;
 
 /*!
- * \brief Base dgl graph class.
+ * \brief Base dgl graph index class.
  *
  * DGL's graph is directed. Vertices are integers enumerated from zero. Edges
  * are uniquely identified by the two endpoints. Multi-edge is currently not
@@ -41,7 +46,7 @@ class Graph {
   } EdgeArray;
 
   /*! \brief default constructor */
-  Graph(bool multigraph = false) : is_multigraph_(multigraph) {}
+  explicit Graph(bool multigraph = false) : is_multigraph_(multigraph) {}
 
   /*! \brief default copy constructor */
   Graph(const Graph& other) = default;
@@ -192,7 +197,7 @@ class Graph {
    * \return the id arrays of the two endpoints of the edges.
    */
   EdgeArray InEdges(IdArray vids) const;
-  
+
   /*!
    * \brief Get the out edges of the vertex.
    * \note The returned src id array is filled with vid.
@@ -347,4 +352,4 @@ struct Subgraph {
 
 }  // namespace dgl
 
-#endif  // DGL_DGLGRAPH_H_
+#endif  // DGL_GRAPH_H_

include/dgl/graph_op.h

-// Graph operations
+/*!
+ *  Copyright (c) 2018 by Contributors
+ * \file dgl/graph_op.h
+ * \brief Operations on graph index.
+ */
 #ifndef DGL_GRAPH_OP_H_
 #define DGL_GRAPH_OP_H_
 
+#include <vector>
 #include "graph.h"
 
 namespace dgl {

include/dgl/runtime/README.md

-# C API and runtime
-
-Borrowed and adapted from TVM project.

include/dgl/runtime/c_backend_api.h

@@ -7,8 +7,8 @@
  *  used by compiled tvm operators, usually user do not need to use these
  *  function directly.
  */
-#ifndef TVM_RUNTIME_C_BACKEND_API_H_
-#define TVM_RUNTIME_C_BACKEND_API_H_
+#ifndef DGL_RUNTIME_C_BACKEND_API_H_
+#define DGL_RUNTIME_C_BACKEND_API_H_
 
 #include "c_runtime_api.h"
 
@@ -136,4 +136,4 @@ TVM_DLL int TVMBackendRunOnce(void** handle,
 #ifdef __cplusplus
 }  // TVM_EXTERN_C
 #endif
-#endif  // TVM_RUNTIME_C_BACKEND_API_H_
+#endif  // DGL_RUNTIME_C_BACKEND_API_H_

include/dgl/runtime/c_runtime_api.h

 /*!
  *  Copyright (c) 2016 by Contributors
- * \file tvm/runtime/c_runtime_api.h
+ * \file dgl/runtime/c_runtime_api.h
  * \brief TVM runtime library.
  *
  *  The philosophy of TVM project is to customize the compilation
@@ -15,8 +15,8 @@
  *   - Use TVMFuncListGlobalNames to get global function name
  *   - Use TVMFuncCall to call these functions.
  */
-#ifndef TVM_RUNTIME_C_RUNTIME_API_H_
-#define TVM_RUNTIME_C_RUNTIME_API_H_
+#ifndef DGL_RUNTIME_C_RUNTIME_API_H_
+#define DGL_RUNTIME_C_RUNTIME_API_H_
 
 // Macros to do weak linking
 #ifdef _MSC_VER
@@ -530,4 +530,4 @@ TVM_DLL int TVMStreamStreamSynchronize(int device_type,
 #ifdef __cplusplus
 }  // TVM_EXTERN_C
 #endif
-#endif  // TVM_RUNTIME_C_RUNTIME_API_H_
+#endif  // DGL_RUNTIME_C_RUNTIME_API_H_

include/dgl/runtime/device_api.h

 /*!
  *  Copyright (c) 2016 by Contributors
- * \file tvm/runtime/device_api.h
+ * \file dgl/runtime/device_api.h
  * \brief Abstract device memory management API
  */
-#ifndef TVM_RUNTIME_DEVICE_API_H_
-#define TVM_RUNTIME_DEVICE_API_H_
+#ifndef DGL_RUNTIME_DEVICE_API_H_
+#define DGL_RUNTIME_DEVICE_API_H_
 
 #include <string>
 #include "packed_func.h"
@@ -180,4 +180,4 @@ class DeviceAPI {
 constexpr int kRPCSessMask = 128;
 }  // namespace runtime
 }  // namespace tvm
-#endif  // TVM_RUNTIME_DEVICE_API_H_
+#endif  // DGL_RUNTIME_DEVICE_API_H_

include/dgl/runtime/module.h

 /*!
  *  Copyright (c) 2017 by Contributors
- * \file tvm/runtime/module.h
+ * \file dgl/runtime/module.h
  * \brief Runtime container of the functions generated by TVM,
  *  This is used to support dynamically link, load and save
  *  functions from different convention under unified API.
  */
-#ifndef TVM_RUNTIME_MODULE_H_
-#define TVM_RUNTIME_MODULE_H_
+#ifndef DGL_RUNTIME_MODULE_H_
+#define DGL_RUNTIME_MODULE_H_
 
 #include <dmlc/io.h>
 #include <memory>
@@ -174,4 +174,4 @@ inline const ModuleNode* Module::operator->() const {
 }  // namespace tvm
 
 #include "packed_func.h"
-#endif  // TVM_RUNTIME_MODULE_H_
+#endif  // DGL_RUNTIME_MODULE_H_

include/dgl/runtime/ndarray.h

 /*!
  *  Copyright (c) 2017 by Contributors
- * \file tvm/runtime/ndarray.h
+ * \file dgl/runtime/ndarray.h
  * \brief Abstract device memory management API
  */
-#ifndef TVM_RUNTIME_NDARRAY_H_
-#define TVM_RUNTIME_NDARRAY_H_
+#ifndef DGL_RUNTIME_NDARRAY_H_
+#define DGL_RUNTIME_NDARRAY_H_
 
 #include <atomic>
 #include <vector>
@@ -422,4 +422,4 @@ inline bool NDArray::Load(dmlc::Stream* strm) {
 
 }  // namespace runtime
 }  // namespace tvm
-#endif  // TVM_RUNTIME_NDARRAY_H_
+#endif  // DGL_RUNTIME_NDARRAY_H_

include/dgl/runtime/packed_func.h

 /*!
  *  Copyright (c) 2017 by Contributors
- * \file tvm/runtime/packed_func.h
+ * \file dgl/runtime/packed_func.h
  * \brief Type-erased function used across TVM API.
  */
-#ifndef TVM_RUNTIME_PACKED_FUNC_H_
-#define TVM_RUNTIME_PACKED_FUNC_H_
+#ifndef DGL_RUNTIME_PACKED_FUNC_H_
+#define DGL_RUNTIME_PACKED_FUNC_H_
 
 #include <dmlc/logging.h>
 #include <functional>
@@ -1212,4 +1212,4 @@ inline PackedFunc Module::GetFunction(const std::string& name, bool query_import
 }
 }  // namespace runtime
 }  // namespace tvm
-#endif  // TVM_RUNTIME_PACKED_FUNC_H_
+#endif  // DGL_RUNTIME_PACKED_FUNC_H_

include/dgl/runtime/registry.h

 /*!
  *  Copyright (c) 2017 by Contributors
- * \file tvm/runtime/registry.h
+ * \file dgl/runtime/registry.h
  * \brief This file defines the TVM global function registry.
  *
  *  The registered functions will be made available to front-end
@@ -22,8 +22,8 @@
  *   });
  * \endcode
  */
-#ifndef TVM_RUNTIME_REGISTRY_H_
-#define TVM_RUNTIME_REGISTRY_H_
+#ifndef DGL_RUNTIME_REGISTRY_H_
+#define DGL_RUNTIME_REGISTRY_H_
 
 #include <string>
 #include <vector>
@@ -141,4 +141,4 @@ class Registry {
 
 }  // namespace runtime
 }  // namespace tvm
-#endif  // TVM_RUNTIME_REGISTRY_H_
+#endif  // DGL_RUNTIME_REGISTRY_H_

include/dgl/runtime/serializer.h

 /*!
  *  Copyright (c) 2017 by Contributors
- * \file tvm/runtime/serializer.h
+ * \file dgl/runtime/serializer.h
  * \brief Serializer extension to support TVM data types
  *  Include this file to enable serialization of DLDataType, DLContext
  */
-#ifndef TVM_RUNTIME_SERIALIZER_H_
-#define TVM_RUNTIME_SERIALIZER_H_
+#ifndef DGL_RUNTIME_SERIALIZER_H_
+#define DGL_RUNTIME_SERIALIZER_H_
 
 #include <dmlc/io.h>
 #include <dmlc/serializer.h>
@@ -48,4 +48,4 @@ struct Handler<DLContext> {
 
 }  // namespace serializer
 }  // namespace dmlc
-#endif  // TVM_RUNTIME_SERIALIZER_H_
+#endif  // DGL_RUNTIME_SERIALIZER_H_

include/dgl/runtime/threading_backend.h

 /*!
  *  Copyright (c) 2018 by Contributors
- * \file tvm/runtime/threading_backend.h
+ * \file dgl/runtime/threading_backend.h
  * \brief Utilities for manipulating thread pool threads.
  */
-#ifndef TVM_RUNTIME_THREADING_BACKEND_H_
-#define TVM_RUNTIME_THREADING_BACKEND_H_
+#ifndef DGL_RUNTIME_THREADING_BACKEND_H_
+#define DGL_RUNTIME_THREADING_BACKEND_H_
 
 #include <functional>
 #include <memory>
@@ -82,4 +82,4 @@ int MaxConcurrency();
 }  // namespace runtime
 }  // namespace tvm
 
-#endif  // TVM_RUNTIME_THREADING_BACKEND_H_
+#endif  // DGL_RUNTIME_THREADING_BACKEND_H_

include/dgl/runtime/util.h

 /*!
  *  Copyright (c) 2017 by Contributors
- * \file tvm/runtime/util.h
+ * \file dgl/runtime/util.h
  * \brief Useful runtime util.
  */
-#ifndef TVM_RUNTIME_UTIL_H_
-#define TVM_RUNTIME_UTIL_H_
+#ifndef DGL_RUNTIME_UTIL_H_
+#define DGL_RUNTIME_UTIL_H_
 
 #include "c_runtime_api.h"
 
@@ -50,4 +50,4 @@ enum TVMStructFieldKind : int {
 }  // namespace intrinsic
 }  // namespace ir
 }  // namespace tvm
-#endif  // TVM_RUNTIME_UTIL_H_
+#endif  // DGL_RUNTIME_UTIL_H_

include/dgl/scheduler.h

-// DGL Scheduler interface
+/*!
+ *  Copyright (c) 2018 by Contributors
+ * \file dgl/scheduler.h
+ * \brief Operations on graph index.
+ */
 #ifndef DGL_SCHEDULER_H_
 #define DGL_SCHEDULER_H_
 
-#include "runtime/ndarray.h"
 #include <vector>
+#include "runtime/ndarray.h"
 
 namespace dgl {
 
@@ -25,8 +29,8 @@ namespace sched {
  */
 std::vector<IdArray> DegreeBucketing(const IdArray& vids);
 
-} // namespace sched
+}  // namespace sched
 
-} // namespace dgl
+}  // namespace dgl
 
-#endif // DGL_SCHEDULER_H_
+#endif  // DGL_SCHEDULER_H_

src/c_api_common.cc

+/*!
+ *  Copyright (c) 2018 by Contributors
+ * \file c_runtime_api.cc
+ * \brief DGL C API common implementations
+ */
 #include "c_api_common.h"
 
 using tvm::runtime::TVMArgs;
@@ -29,5 +34,5 @@ PackedFunc ConvertNDArrayVectorToPackedFunc(const std::vector<NDArray>& vec) {
     return PackedFunc(body);
 }
 
-} // namespace dgl
+}  // namespace dgl
 

src/c_api_common.h

-// DGL C API common util functions
+/*!
+ *  Copyright (c) 2018 by Contributors
+ * \file c_api_common.h
+ * \brief DGL C API common util functions
+ */
 #ifndef DGL_C_API_COMMON_H_
 #define DGL_C_API_COMMON_H_
 
@@ -12,12 +16,20 @@ namespace dgl {
 // Graph handler type
 typedef void* GraphHandle;
 
-// Convert the given DLTensor to a temporary DLManagedTensor that does not own memory.
-DLManagedTensor* CreateTmpDLManagedTensor(const tvm::runtime::TVMArgValue& arg);
+/*!
+ * \brief Convert the given DLTensor to DLManagedTensor.
+ *
+ * Return a temporary DLManagedTensor that does not own memory.
+ */
+DLManagedTensor* CreateTmpDLManagedTensor(
+    const tvm::runtime::TVMArgValue& arg);
 
-// Convert a vector of NDArray to PackedFunc
-tvm::runtime::PackedFunc ConvertNDArrayVectorToPackedFunc(const std::vector<tvm::runtime::NDArray>& vec);
+/*!
+ * \brief Convert a vector of NDArray to PackedFunc.
+ */
+tvm::runtime::PackedFunc ConvertNDArrayVectorToPackedFunc(
+    const std::vector<tvm::runtime::NDArray>& vec);
 
-} // namespace dgl
+}  // namespace dgl
 
-#endif // DGL_C_API_COMMON_H_
+#endif  // DGL_C_API_COMMON_H_

src/graph/graph.cc

-// Graph class implementation
+/*!
+ *  Copyright (c) 2018 by Contributors
+ * \file graph/graph.cc
+ * \brief DGL graph index implementation
+ */
+#include <dgl/graph.h>
 #include <algorithm>
 #include <unordered_map>
 #include <set>
 #include <functional>
-#include <dgl/graph.h>
 
 namespace dgl {
 namespace {
@@ -193,9 +197,9 @@ Graph::EdgeArray Graph::EdgeIds(IdArray src_ids, IdArray dst_ids) const {
     const auto& succ = adjlist_[src_id].succ;
     for (size_t k = 0; k < succ.size(); ++k) {
       if (succ[k] == dst_id) {
-	src.push_back(src_id);
-	dst.push_back(dst_id);
-	eid.push_back(adjlist_[src_id].edge_id[k]);
+        src.push_back(src_id);
+        dst.push_back(dst_id);
+        eid.push_back(adjlist_[src_id].edge_id[k]);
       }
     }
   }
@@ -351,7 +355,7 @@ Graph::EdgeArray Graph::Edges(bool sorted) const {
           return std::get<0>(t1) < std::get<0>(t2)
             || (std::get<0>(t1) == std::get<0>(t2) && std::get<1>(t1) < std::get<1>(t2));
         });
-    
+
     // make return arrays
     int64_t* src_ptr = static_cast<int64_t*>(src->data);
     int64_t* dst_ptr = static_cast<int64_t*>(dst->data);
@@ -461,7 +465,8 @@ Subgraph Graph::EdgeSubgraph(IdArray eids) const {
     rst.graph.AddEdge(oldv2newv[src_id], oldv2newv[dst_id]);
   }
 
-  rst.induced_vertices = IdArray::Empty({static_cast<int64_t>(nodes.size())}, eids->dtype, eids->ctx);
+  rst.induced_vertices = IdArray::Empty(
+      {static_cast<int64_t>(nodes.size())}, eids->dtype, eids->ctx);
   std::copy(nodes.begin(), nodes.end(), static_cast<int64_t*>(rst.induced_vertices->data));
 
   return rst;

src/graph/graph_apis.cc

+/*!
+ *  Copyright (c) 2018 by Contributors
+ * \file graph/graph.cc
+ * \brief DGL graph index APIs
+ */
 #include <dgl/graph.h>
 #include <dgl/graph_op.h>
 #include "../c_api_common.h"

src/graph/graph_op.cc

-// Graph operation implementation
+/*!
+ *  Copyright (c) 2018 by Contributors
+ * \file graph/graph.cc
+ * \brief Graph operation implementation
+ */
 #include <dgl/graph_op.h>
 #include <algorithm>
 
 namespace dgl {
 
-Graph GraphOp::LineGraph(const Graph* g, bool backtracking){
+Graph GraphOp::LineGraph(const Graph* g, bool backtracking) {
   typedef std::pair<dgl_id_t, dgl_id_t> entry;
-  typedef std::map<dgl_id_t, std::vector<entry>> csm; // Compressed Sparse Matrix
+  typedef std::map<dgl_id_t, std::vector<entry>> csm;  // Compressed Sparse Matrix
 
   csm adj;
   std::vector<entry> vec;
@@ -67,7 +71,7 @@ std::vector<Graph> GraphOp::DisjointPartitionByNum(const Graph* graph, int64_t n
   std::fill(sizes_data, sizes_data + num, graph->NumVertices() / num);
   return DisjointPartitionBySizes(graph, sizes);
 }
-  
+
 std::vector<Graph> GraphOp::DisjointPartitionBySizes(const Graph* graph, IdArray sizes) {
   const int64_t len = sizes->shape[0];
   const int64_t* sizes_data = static_cast<int64_t*>(sizes->data);
@@ -117,32 +121,6 @@ std::vector<Graph> GraphOp::DisjointPartitionBySizes(const Graph* graph, IdArray
     node_offset += sizes_data[i];
     edge_offset += num_edges;
   }
-  /*for (int64_t i = 0; i < len; ++i) {
-    rst[i].AddVertices(sizes_data[i]);
-  }
-  for (dgl_id_t eid = 0; eid < graph->num_edges_; ++eid) {
-    const dgl_id_t src = graph->all_edges_src_[eid];
-    const dgl_id_t dst = graph->all_edges_dst_[eid];
-    size_t src_select = 0, dst_select = 0;
-    for (size_t i = 1; i < cumsum.size(); ++i) { // TODO: replace with binary search
-      if (cumsum[i] > src) {
-        src_select = i;
-        break;
-      }
-    }
-    for (size_t i = 1; i < cumsum.size(); ++i) { // TODO: replace with binary search
-      if (cumsum[i] > dst) {
-        dst_select = i;
-        break;
-      }
-    }
-    if (src_select != dst_select) {
-      // the edge is ignored if across two partitions
-      continue;
-    }
-    const int64_t offset = cumsum[src_select - 1];
-    rst[src_select - 1].AddEdge(src - offset, dst - offset);
-  }*/
   return rst;
 }
 

src/runtime/README.md

-# C API and runtime
-
-Borrowed and adapted from TVM project.