[generator] Stubs for incremental updates.

generator/CMakeLists.txt

@@ -108,6 +108,8 @@ add_library(${PROJECT_NAME} ${SRC})
 omim_add_test_subdirectory(generator_tests_support)
 omim_add_test_subdirectory(generator_tests)
 
+add_subdirectory(mwm_diff)
+
 if (NOT SKIP_GTOOL)
   add_subdirectory(generator_tool)
 endif()

generator/mwm_diff/CMakeLists.txt

@@ -0,0 +1,12 @@
+project(mwm_diff)
+
+set(
+  SRC
+  diff.cpp
+  diff.hpp
+)
+
+add_library(${PROJECT_NAME} ${SRC})
+
+omim_add_pybindings_subdirectory(pymwm_diff)
+omim_add_test_subdirectory(mwm_diff_tests)

generator/mwm_diff/diff.cpp

@@ -0,0 +1,56 @@
+#include "generator/mwm_diff/diff.hpp"
+
+#include "coding/file_reader.hpp"
+#include "coding/file_writer.hpp"
+#include "coding/read_write_utils.hpp"
+#include "coding/reader.hpp"
+
+#include "base/logging.hpp"
+
+using namespace std;
+
+namespace
+{
+// We could use my::CopyFileX but it fails if the file at |srcFile| is empty.
+bool CopyFile(string const & srcFile, string const & dstFile)
+{
+  size_t constexpr kBufferSize = 1024 * 1024;
+
+  try
+  {
+    FileReader reader(srcFile, true /* withExceptions */);
+    ReaderSource<FileReader> src(reader);
+    FileWriter writer(dstFile);
+
+    rw::ReadAndWrite(src, writer, kBufferSize);
+  }
+  catch (Reader::Exception const & e)
+  {
+    LOG(LERROR, ("Could not read from", srcFile, ":", e.Msg()));
+    return false;
+  }
+  catch (Writer::Exception const & e)
+  {
+    LOG(LERROR, ("Could not write to", dstFile, ":", e.Msg()));
+    return false;
+  }
+
+  return true;
+}
+}  // namespace
+
+namespace generator
+{
+namespace mwm_diff
+{
+bool MakeDiff(string const & /* oldMwmPath */, string const & newMwmPath, string const & diffPath)
+{
+  return CopyFile(newMwmPath, diffPath);
+}
+
+bool ApplyDiff(string const & /* oldMwmPath */, string const & newMwmPath, string const & diffPath)
+{
+  return CopyFile(diffPath, newMwmPath);
+}
+}  // namespace mwm_diff
+}  // namespace generator

generator/mwm_diff/diff.hpp

@@ -0,0 +1,24 @@
+#pragma once
+
+#include <string>
+
+namespace generator
+{
+namespace mwm_diff
+{
+// Makes a diff that, when applied to the mwm at |oldMwmPath|, will
+// result in the mwm at |newMwmPath|. The diff is stored at |diffPath|.
+// It is assumed that the files at |oldMwmPath| and |newMwmPath| are valid mwms.
+// Returns true on success and false on failure.
+bool MakeDiff(std::string const & /* oldMwmPath */, std::string const & newMwmPath,
+              std::string const & diffPath);
+
+// Applies the diff at |diffPath| to the mwm at |oldMwmPath|. The resulting
+// mwm is stored at |newMwmPath|.
+// It is assumed that the file at |oldMwmPath| is a valid mwm and the file
+// at |diffPath| is a valid mwmdiff.
+// Returns true on success and false on failure.
+bool ApplyDiff(std::string const & /* oldMwmPath */, std::string const & newMwmPath,
+               std::string const & diffPath);
+}  // namespace mwm_diff
+}  // namespace generator

generator/mwm_diff/mwm_diff_tests/CMakeLists.txt

@@ -0,0 +1,51 @@
+project(mwm_diff_tests)
+
+set(
+  SRC
+  diff_test.cpp
+)
+
+omim_add_test(${PROJECT_NAME} ${SRC})
+
+omim_link_libraries(
+  ${PROJECT_NAME}
+  generator_tests_support
+  platform_tests_support
+  mwm_diff
+  generator
+  drape_frontend
+  map
+  routing
+  search
+  storage
+  indexer
+  drape
+  traffic
+  routing_common
+  editor
+  platform
+  geometry
+  coding
+  base
+  freetype
+  expat
+  icu
+  jansson
+  protobuf
+  osrm
+  stats_client
+  minizip
+  succinct
+  pugixml
+  tess2
+  gflags
+  oauthcpp
+  opening_hours
+  stb_image
+  sdf_image
+  # TODO(syershov): Use FindPackage.
+  sqlite3
+  ${LIBZ}
+)
+
+link_qt5_core(${PROJECT_NAME})

generator/mwm_diff/mwm_diff_tests/diff_test.cpp

@@ -0,0 +1,45 @@
+#include "testing/testing.hpp"
+
+#include "generator/mwm_diff/diff.hpp"
+
+#include "platform/platform.hpp"
+
+#include "coding/file_name_utils.hpp"
+#include "coding/file_writer.hpp"
+#include "coding/internal/file_data.hpp"
+
+#include "base/scope_guard.hpp"
+
+using namespace std;
+
+namespace generator
+{
+namespace mwm_diff
+{
+UNIT_TEST(IncrementalUpdates_Smoke)
+{
+  string const oldMwmPath = my::JoinFoldersToPath(GetPlatform().WritableDir(), "minsk-pass.mwm");
+  string const newMwmPath1 =
+      my::JoinFoldersToPath(GetPlatform().WritableDir(), "minsk-pass-new1.mwm");
+  string const newMwmPath2 =
+      my::JoinFoldersToPath(GetPlatform().WritableDir(), "minsk-pass-new2.mwm");
+  string const diffPath = my::JoinFoldersToPath(GetPlatform().WritableDir(), "minsk-pass.mwmdiff");
+
+  MY_SCOPE_GUARD(cleanup, [&] {
+    FileWriter::DeleteFileX(newMwmPath1);
+    FileWriter::DeleteFileX(newMwmPath2);
+    FileWriter::DeleteFileX(diffPath);
+  });
+
+  {
+    // Create an empty file.
+    FileWriter writer(newMwmPath1);
+  }
+
+  TEST(MakeDiff(oldMwmPath, newMwmPath1, diffPath), ());
+  TEST(ApplyDiff(oldMwmPath, newMwmPath2, diffPath), ());
+
+  TEST(my::IsEqualFiles(newMwmPath1, newMwmPath2), ());
+}
+}  // namespace mwm_diff
+}  // namespace generator

generator/mwm_diff/pymwm_diff/CMakeLists.txt

@@ -0,0 +1,45 @@
+project(pymwm_diff)
+
+set(
+  SRC
+  bindings.cpp
+)
+
+add_library(${PROJECT_NAME} MODULE ${SRC})
+
+if (PLATFORM_MAC)
+  omim_link_libraries(
+    ${PROJECT_NAME}
+    ${Qt5Widgets_LIBRARIES}
+  )
+endif()
+
+if (PLATFORM_WIN OR PLATFORM_LINUX)
+  omim_link_libraries(
+    ${PROJECT_NAME}
+    ${Qt5Widgets_LIBRARIES}
+  )
+endif()
+
+omim_link_libraries(
+  ${PROJECT_NAME}
+  mwm_diff
+  indexer
+  editor
+  platform
+  geometry
+  coding
+  base
+  stats_client
+  jansson
+  oauthcpp
+  protobuf
+  pugixml
+  opening_hours
+  icu
+  ${PYTHON_LIBRARIES}
+  ${Boost_LIBRARIES}
+  ${LIBZ}
+)
+
+set_target_properties(${PROJECT_NAME} PROPERTIES PREFIX "")

generator/mwm_diff/pymwm_diff/bindings.cpp

@@ -0,0 +1,13 @@
+#include "generator/mwm_diff/diff.hpp"
+
+#include <boost/python.hpp>
+
+using namespace std;
+
+BOOST_PYTHON_MODULE(pymwm_diff)
+{
+  using namespace boost::python;
+
+  def("make_diff", generator::mwm_diff::MakeDiff);
+  def("apply_diff", generator::mwm_diff::ApplyDiff);
+}