Workaround broken gnumake realpath on Windows.

Also, added missing build scripts for flatc on Windows and fixed
numerous issues in the flatbuffers/android/jni/include.mk makefile.

Tested:
Verified dependent project (motive) can generate flatbuffers headers
with these changes on Android.

Bug: 25780616

Change-Id: I73f0dec8f7a6a7eb4e71951a8f1cd3e0d343a9ff

android/jni/Android.mk

@@ -14,26 +14,29 @@
 # misrepresented as being the original software.
 # 3. This notice may not be removed or altered from any source distribution.
 
-LOCAL_PATH := $(call my-dir)
+LOCAL_PATH := $(call my-dir)/../..
+
+include $(LOCAL_PATH)/android/jni/include.mk
+LOCAL_PATH := $(call realpath-portable,$(LOCAL_PATH))
 
 # Empty static library so that other projects can include FlatBuffers as a
 # module.
 include $(CLEAR_VARS)
 LOCAL_MODULE := flatbuffers
-LOCAL_EXPORT_C_INCLUDES := $(LOCAL_PATH)/../../include
+LOCAL_EXPORT_C_INCLUDES := $(LOCAL_PATH)/include
 LOCAL_EXPORT_CPPFLAGS := -std=c++11 -fexceptions -Wall -Wno-literal-suffix
 include $(BUILD_STATIC_LIBRARY)
 
 # FlatBuffers test
 include $(CLEAR_VARS)
 LOCAL_MODULE := FlatBufferTest
-LOCAL_SRC_FILES := main.cpp \
-                   ../../tests/test.cpp \
-                   ../../src/idl_parser.cpp \
-                   ../../src/idl_gen_text.cpp \
-                   ../../src/idl_gen_fbs.cpp \
-                   ../../src/idl_gen_general.cpp \
-                   ../../src/reflection.cpp
+LOCAL_SRC_FILES := android/jni/main.cpp \
+                   tests/test.cpp \
+                   src/idl_parser.cpp \
+                   src/idl_gen_text.cpp \
+                   src/idl_gen_fbs.cpp \
+                   src/idl_gen_general.cpp \
+                   src/reflection.cpp
 LOCAL_LDLIBS := -llog -landroid
 LOCAL_STATIC_LIBRARIES := android_native_app_glue flatbuffers
 LOCAL_ARM_MODE := arm
@@ -41,4 +44,4 @@ include $(BUILD_SHARED_LIBRARY)
 
 $(call import-module,android/native_app_glue)
 
-$(call import-add-path,../..)
+$(call import-add-path,$(LOCAL_PATH)/../..)

android/jni/build_flatc.bat

+@rem Copyright (c) 2013 Google, Inc.
+@rem
+@rem This software is provided 'as-is', without any express or implied
+@rem warranty.  In no event will the authors be held liable for any damages
+@rem arising from the use of this software.
+@rem Permission is granted to anyone to use this software for any purpose,
+@rem including commercial applications, and to alter it and redistribute it
+@rem freely, subject to the following restrictions:
+@rem 1. The origin of this software must not be misrepresented; you must not
+@rem claim that you wrote the original software. If you use this software
+@rem in a product, an acknowledgment in the product documentation would be
+@rem appreciated but is not required.
+@rem 2. Altered source versions must be plainly marked as such, and must not be
+@rem misrepresented as being the original software.
+@rem 3. This notice may not be removed or altered from any source distribution.
+@echo off
+
+setlocal enabledelayedexpansion
+
+set thispath=%~dp0
+
+rem Path to cmake passed in by caller.
+set cmake=%1
+rem Path to cmake project to build.
+set cmake_project_path=%2
+
+rem Newest and oldest version of Visual Studio that it's possible to select.
+set visual_studio_version_max=20
+set visual_studio_version_min=8
+
+rem Determine the newest version of Visual Studio installed on this machine.
+set visual_studio_version=
+for /L %%a in (%visual_studio_version_max%,-1,%visual_studio_version_min%) do (
+  echo Searching for Visual Studio %%a >&2
+  reg query HKLM\SOFTWARE\Microsoft\VisualStudio\%%a.0 /ve 1>NUL 2>NUL
+  if !ERRORLEVEL! EQU 0 (
+    set visual_studio_version=%%a
+    goto found_vs
+  )
+)
+echo Unable to determine whether Visual Studio is installed. >&2
+exit /B 1
+:found_vs
+
+rem Map Visual Studio version to cmake generator name.
+if "%visual_studio_version%"=="8" (
+  set cmake_generator=Visual Studio 8 2005
+)
+if "%visual_studio_version%"=="9" (
+  set cmake_generator=Visual Studio 9 2008
+)
+if %visual_studio_version% GEQ 10 (
+  set cmake_generator=Visual Studio %visual_studio_version%
+)
+rem Set visual studio version variable for msbuild.
+set VisualStudioVersion=%visual_studio_version%.0
+
+rem Generate Visual Studio solution.
+echo Generating solution for %cmake_generator%. >&2
+cd "%cmake_project_path%"
+%cmake% -G"%cmake_generator%"
+if %ERRORLEVEL% NEQ 0 (
+  exit /B %ERRORLEVEL%
+)
+
+rem Build flatc
+python %thispath%\msbuild.py flatc.vcxproj
+if ERRORLEVEL 1 exit /B 1

android/jni/include.mk

@@ -37,6 +37,10 @@
 ifeq (,$(FLATBUFFERS_INCLUDE_MK_))
 FLATBUFFERS_INCLUDE_MK_ := 1
 
+# Portable version of $(realpath) that omits drive letters on Windows.
+realpath-portable = $(join $(filter %:,$(subst :,: ,$1)),\
+                      $(realpath $(filter-out %:,$(subst :,: ,$1))))
+
 PROJECT_OS := $(OS)
 ifeq (,$(OS))
 PROJECT_OS := $(shell uname -s)
@@ -50,26 +54,31 @@ endif
 # rebuilt from flatbuffers schemas.
 
 FLATBUFFERS_CMAKELISTS_DIR := \
-  $(realpath $(dir $(lastword $(MAKEFILE_LIST)))/../..)
+  $(call realpath-portable,$(dir $(lastword $(MAKEFILE_LIST)))/../..)
 
 # Directory that contains the FlatBuffers compiler.
 ifeq (Windows,$(PROJECT_OS))
-FLATBUFFERS_FLATC_PATH?=$(CURDIR)/bin
-FLATBUFFERS_FLATC := $(FLATBUFFERS_FLATC_PATH)/Debug/flatc.exe
+FLATBUFFERS_FLATC_PATH?=$(FLATBUFFERS_CMAKELISTS_DIR)
+FLATBUFFERS_FLATC := $(lastword \
+                       $(wildcard $(FLATBUFFERS_FLATC_PATH)/*/flatc.exe) \
+                       $(wildcard $(FLATBUFFERS_FLATC_PATH)/flatc.exe))
 endif
 ifeq (Linux,$(PROJECT_OS))
-FLATBUFFERS_FLATC_PATH?=$(CURDIR)/bin
+FLATBUFFERS_FLATC_PATH?=$(FLATBUFFERS_CMAKELISTS_DIR)
 FLATBUFFERS_FLATC := $(FLATBUFFERS_FLATC_PATH)/flatc
 endif
 ifeq (Darwin,$(PROJECT_OS))
 FLATBUFFERS_FLATC_PATH?=$(FLATBUFFERS_CMAKELISTS_DIR)
-FLATBUFFERS_FLATC := $(FLATBUFFERS_FLATC_PATH)/Debug/flatc
+FLATBUFFERS_FLATC := $(lastword \
+                       $(wildcard $(FLATBUFFERS_FLATC_PATH)/*/flatc) \
+                       $(wildcard $(FLATBUFFERS_FLATC_PATH)/flatc))
 endif
 
 FLATBUFFERS_FLATC_ARGS?=
 
 # Search for cmake.
-CMAKE_ROOT := $(realpath $(LOCAL_PATH)/../../../../../../prebuilts/cmake)
+CMAKE_ROOT := \
+  $(call realpath-portable,$(LOCAL_PATH)/../../../../../../prebuilts/cmake)
 ifeq (,$(CMAKE))
 ifeq (Linux,$(PROJECT_OS))
 CMAKE := $(wildcard $(CMAKE_ROOT)/linux-x86/current/bin/cmake*)
@@ -97,15 +106,14 @@ endif
 # Generate a host build rule for the flatbuffers compiler.
 ifeq (Windows,$(PROJECT_OS))
 define build_flatc_recipe
-	cd  & jni\build_flatc.bat $(CMAKE)
+	$(FLATBUFFERS_CMAKELISTS_DIR)\android\jni\build_flatc.bat \
+        $(CMAKE) $(FLATBUFFERS_CMAKELISTS_DIR)
 endef
 endif
 ifeq (Linux,$(PROJECT_OS))
 define build_flatc_recipe
-	+mkdir -p bin && \
-      cd bin && \
-      $(CMAKE) \
-      $(FLATBUFFERS_CMAKELISTS_DIR) && \
+	+cd $(FLATBUFFERS_CMAKELISTS_DIR) && \
+      $(CMAKE) && \
       $(MAKE) flatc
 endef
 endif
@@ -125,6 +133,9 @@ endif
 ifeq ($(strip $(FLATBUFFERS_FLATC)),)
 flatc_target := build_flatc
 .PHONY: $(flatc_target)
+FLATBUFFERS_FLATC := \
+  python $(FLATBUFFERS_CMAKELISTS_DIR)/android/jni/run_flatc.py \
+    $(FLATBUFFERS_CMAKELISTS_DIR)
 else
 flatc_target := $(FLATBUFFERS_FLATC)
 endif
@@ -166,6 +177,15 @@ $(eval \
       $(foreach include,$(4),-I $(include)) -o $$(dir $$@) -c $$<)
 endef
 
+# TODO: Remove when the LOCAL_PATH expansion bug in the NDK is fixed.
+# Override the default behavior of local-source-file-path to workaround
+# a bug which prevents the build of deeply nested projects when NDK_OUT is
+# set.
+local-source-file-path=\
+$(if $(call host-path-is-absolute,$1),$1,$(call \
+    realpath-portable,$(LOCAL_PATH)/$1))
+
+
 # $(flatbuffers_header_build_rules schema_files,schema_dir,output_dir,\
 #   schema_include_dirs,src_files,[build_target],[dependencies]))
 #
@@ -187,6 +207,13 @@ endef
 # $(call flatbuffers_header_build_rules,$(MY_PROJ_SCHEMA_FILES),\
 #   $(MY_PROJ_SCHEMA_DIR),$(MY_PROJ_GENERATED_OUTPUT_DIR),
 #   $(MY_PROJ_SCHEMA_INCLUDE_DIRS),$(LOCAL_SRC_FILES))
+#
+# NOTE: Due problesm with path processing in ndk-build when presented with
+# deeply nested projects must redefine LOCAL_PATH after include this makefile
+# using:
+#
+# LOCAL_PATH := $(call realpath-portable,$(LOCAL_PATH))
+#
 define flatbuffers_header_build_rules
 $(foreach schema,$(1),\
   $(call flatbuffers_header_build_rule,\
@@ -207,12 +234,4 @@ $(if $(7),\
       $(eval $(6): $(dependency))),)
 endef
 
-# TODO: Remove when the LOCAL_PATH expansion bug in the NDK is fixed.
-# Override the default behavior of local-source-file-path to workaround
-# a bug which prevents the build of deeply nested projects when NDK_OUT is
-# set.
-local-source-file-path = \
-  $(if $(call host-path-is-absolute,$1),$1,$(realpath $(LOCAL_PATH)/$1))
-
 endif  # FLATBUFFERS_INCLUDE_MK_
-

android/jni/msbuild.py

+#!/usr/bin/python
+# Copyright 2014 Google Inc. All rights reserved.
+#
+# 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.
+
+"""Simple script that locates the newest MSBuild in one of several locations.
+
+This script will find the highest version number of MSBuild and run it,
+passing its arguments through to MSBuild.
+"""
+
+import glob
+import os
+import re
+import string
+import subprocess
+import sys
+
+SYSTEMROOT = os.getenv("SYSTEMROOT", "c:\\windows")
+PROGRAM_FILES = os.getenv("ProgramFiles", "c:\\Program Files")
+PROGRAM_FILES_X86 = os.getenv("ProgramFiles(x86)", "c:\\Program Files (x86)")
+
+SEARCH_FOLDERS = [ PROGRAM_FILES + "\\MSBuild\\*\\Bin\\MSBuild.exe",
+                   PROGRAM_FILES_X86 + "\\MSBuild\\*\\Bin\\MSBuild.exe",
+                   SYSTEMROOT + "\\Microsoft.NET\Framework\\*\\MSBuild.exe" ]
+
+def compare_version(a, b):
+  """Compare two version number strings of the form W.X.Y.Z.
+
+  The numbers are compared most-significant to least-significant.
+  For example, 12.345.67.89 > 2.987.88.99.
+
+  Args:
+    a: First version number string to compare
+    b: Second version number string to compare
+
+  Returns:
+    0 if the numbers are identical, a positive number if 'a' is larger, and
+    a negative number if 'b' is larger.
+  """
+  aa = string.split(a, ".")
+  bb = string.split(b, ".")
+  for i in range(0, 4):
+    if aa[i] != bb[i]:
+      return cmp(int(aa[i]), int(bb[i]))
+  return 0
+
+def main():
+  msbuilds = []
+
+  for folder in SEARCH_FOLDERS:
+    for file in glob.glob(folder):
+      p = subprocess.Popen([file, "/version"], stdout=subprocess.PIPE)
+      out, err = p.communicate()
+      match = re.search("^[0-9]+\\.[0-9]+\\.[0-9]+\\.[0-9]+$", out, re.M)
+      if match:
+        msbuilds.append({ 'ver':match.group(), 'exe':file })
+  msbuilds.sort(lambda x, y: compare_version(x['ver'], y['ver']), reverse=True)
+  if len(msbuilds) == 0:
+    print "Unable to find MSBuild.\n"
+    return -1;
+  cmd = [msbuilds[0]['exe']]
+  cmd.extend(sys.argv[1:])
+  return subprocess.call(cmd)
+
+if __name__ == '__main__':
+  sys.exit(main())

android/jni/run_flatc.py

+#!/usr/bin/python
+# Copyright 2015 Google Inc. All rights reserved.
+#
+# 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.
+
+import os
+import platform
+import subprocess
+import sys
+
+EXECUTABLE_EXTENSION = '.exe' if platform.system() == 'Windows' else ''
+# Paths to search for flatc relative to the current working directory.
+FLATC_SEARCH_PATHS = [os.path.curdir, 'Release', 'Debug']
+
+def main():
+  """Script that finds and runs flatc built from source."""
+  if len(sys.argv) < 2:
+    sys.stderr.write('Usage: run_flatc.py flatbuffers_dir [flatc_args]\n')
+    return 1
+  cwd = os.getcwd()
+  flatc = ''
+  flatbuffers_dir = sys.argv[1]
+  for path in FLATC_SEARCH_PATHS:
+    current = os.path.join(flatbuffers_dir, path,
+                           'flatc' + EXECUTABLE_EXTENSION)
+    if os.path.exists(current):
+      flatc = current
+      break
+  if not flatc:
+    sys.stderr.write('flatc not found\n')
+    return 1
+  command = [flatc] + sys.argv[2:]
+  return subprocess.call(command)
+
+if __name__ == '__main__':
+  sys.exit(main())