Add a way for users to provide local directories for external libraries

a-maurice · a-maurice · commit 5c15a6e7afac · 2019-05-07T11:07:46.000-07:00
Allow the users to provide their own directories for all the external libraries that are downloaded as part of the build process, by overriding name_SOURCE_DIR and name_BINARY_DIR.

PiperOrigin-RevId: 246938364
diff --git a/CMakeLists.txt b/CMakeLists.txt
@@ -88,8 +88,7 @@ set(FLATBUFFERS_BUILD_TESTS OFF CACHE BOOL "")
 
 # Add flatbuffers as a subdirectory, and set the directory variables for it,
 # so that the sub Firebase projects can depend upon it if necessary.
-add_external_subdirectory(flatbuffers)
-populate_external_source_vars(flatbuffers)
+add_external_library(flatbuffers)
 
 # Some of the external libraries are not used for mobile.
 if (NOT ANDROID AND NOT IOS)
@@ -98,18 +97,15 @@ if (NOT ANDROID AND NOT IOS)
   if (WIN32)
     set(CMAKE_USE_WINSSL ON CACHE BOOL "")
   endif()
-  add_external_subdirectory(curl)
-  populate_external_source_vars(curl)
+  add_external_library(curl)
 
-  add_external_subdirectory(libuv)
-  populate_external_source_vars(libuv)
+  add_external_library(libuv)
 
   find_package(OpenSSL)
 
-  add_external_subdirectory(zlib)
-  populate_external_source_vars(zlib)
+  add_external_library(zlib)
 
-  populate_external_source_vars(uWebSockets)
+  add_external_library(uWebSockets)
   # uWebSockets does not come with a CMakeLists file, so define the target.
   # Note that since it depends on OpenSSL, only do so if that was found.
   if (OPENSSL_FOUND)
@@ -118,18 +114,18 @@ if (NOT ANDROID AND NOT IOS)
     else()
       # Epoll is only used on Linux, otherwise LibUV is used.
       set(uWebSockets_extra_src
-          ${uWebSockets_SOURCE_DIR}/src/Epoll.cpp)
+          ${UWEBSOCKETS_SOURCE_DIR}/src/Epoll.cpp)
     endif()
     add_library(libuWS STATIC
         ${uWebSockets_extra_src}
-        ${uWebSockets_SOURCE_DIR}/src/Extensions.cpp
-        ${uWebSockets_SOURCE_DIR}/src/Group.cpp
-        ${uWebSockets_SOURCE_DIR}/src/HTTPSocket.cpp
-        ${uWebSockets_SOURCE_DIR}/src/Hub.cpp
-        ${uWebSockets_SOURCE_DIR}/src/Networking.cpp
-        ${uWebSockets_SOURCE_DIR}/src/Node.cpp
-        ${uWebSockets_SOURCE_DIR}/src/Socket.cpp
-        ${uWebSockets_SOURCE_DIR}/src/WebSocket.cpp)
+        ${UWEBSOCKETS_SOURCE_DIR}/src/Extensions.cpp
+        ${UWEBSOCKETS_SOURCE_DIR}/src/Group.cpp
+        ${UWEBSOCKETS_SOURCE_DIR}/src/HTTPSocket.cpp
+        ${UWEBSOCKETS_SOURCE_DIR}/src/Hub.cpp
+        ${UWEBSOCKETS_SOURCE_DIR}/src/Networking.cpp
+        ${UWEBSOCKETS_SOURCE_DIR}/src/Node.cpp
+        ${UWEBSOCKETS_SOURCE_DIR}/src/Socket.cpp
+        ${UWEBSOCKETS_SOURCE_DIR}/src/WebSocket.cpp)
     if(MSVC)
       set(websockets_additional_defines
         -DWIN32_LEAN_AND_MEAN # Ensure that windows doesn't include winsock.h by
@@ -149,10 +145,10 @@ if (NOT ANDROID AND NOT IOS)
     )
     target_include_directories(libuWS
       PUBLIC
-        ${libuv_SOURCE_DIR}/include
-        ${uWebSockets_SOURCE_DIR}
-        ${zlib_SOURCE_DIR}
-        ${zlib_BINARY_DIR}
+        ${LIBUV_SOURCE_DIR}/include
+        ${UWEBSOCKETS_SOURCE_DIR}
+        ${ZLIB_SOURCE_DIR}
+        ${ZLIB_BINARY_DIR}
       PRIVATE
         ${OPENSSL_INCLUDE_DIR}
     )
@@ -167,19 +163,18 @@ if (NOT ANDROID AND NOT IOS)
   find_package(Protobuf)
   if (PROTOBUF_FOUND)
     # NanoPB requires Protobuf to be present, so only add it if it was found.
-    add_external_subdirectory(nanopb)
-    populate_external_source_vars(nanopb)
+    add_external_library(nanopb)
     # NanoPB has a FindNanopb which defines the function to generate files, so
     # add it to the module path, and use that.
-    list(INSERT CMAKE_MODULE_PATH 0 ${nanopb_SOURCE_DIR}/extra)
+    list(INSERT CMAKE_MODULE_PATH 0 ${NANOPB_SOURCE_DIR}/extra)
     find_package(Nanopb)
   endif()
 endif()
 
 if(ANDROID OR IOS)
   # Mobile platforms build flatc externally so that it works on the platform
   # performing the build.
-  set(firebase_external_flatc_build_dir "${flatbuffers_BINARY_DIR}-flatc")
+  set(firebase_external_flatc_build_dir "${FLATBUFFERS_BINARY_DIR}-flatc")
   set(firebase_external_flatc "${firebase_external_flatc_build_dir}/flatc")
 
   if(CMAKE_HOST_SYSTEM_NAME STREQUAL "Windows")
@@ -224,7 +219,7 @@ if(ANDROID OR IOS)
   add_custom_command(
     OUTPUT ${firebase_external_flatc}
     COMMAND cd ${firebase_external_flatc_build_dir} ${COMMAND_CONCAT}
-            ${ENV_COMMAND} cmake ${flatbuffers_SOURCE_DIR} ${COMMAND_CONCAT}
+            ${ENV_COMMAND} cmake ${FLATBUFFERS_SOURCE_DIR} ${COMMAND_CONCAT}
             ${ENV_COMMAND} cmake --build . --target flatc
     COMMENT "Building flatc (the FlatBuffer schema compiler)")
 
diff --git a/README.md b/README.md
@@ -119,6 +119,34 @@ cmake -G “Visual Studio 15 2017” ..
 More information on generators can be found at
 <https://cmake.org/cmake/help/latest/manual/cmake-generators.7.html>.
 
+By default, when building the SDK, the CMake process will download any third
+party dependencies that are needed for the build. This logic is in
+[cmake/external_rules.cmake](/cmake/external_rules.cmake), and the accompanying
+[cmake/external/CMakeLists.txt](/cmake/external/CMakeLists.txt). If you would
+like to provide your own directory for these dependencies, you can override
+`[[dependency_name]]_SOURCE_DIR` and `[[dependency_name]]_BINARY_DIR`. If the
+binary directory is not provided, it defaults to the given source directory,
+appended with `-build`.
+
+For example, to provide a custom flatbuffer directory you could run:
+
+``` bash
+cmake -DFLATBUFFERS_SOURCE_DIR=/tmp/flatbuffers ..
+```
+
+And the binary directory would automatically be set to `/tmp/flatbuffers-build`.
+
+Currently, the third party libraries that can be provided this way are:
+
+| Library |
+| ------- |
+| CURL |
+| FLATBUFFERS |
+| LIBUV |
+| NANOPB |
+| UWEBSOCKETS |
+| ZLIB |
+
 #### Building with CMake for iOS
 The Firebase C++ SDK comes with a CMake config file to build the library for
 iOS platforms, [cmake/ios.cmake](/cmake/ios.cmake).  In order to build with it,
diff --git a/app/CMakeLists.txt b/app/CMakeLists.txt
@@ -248,7 +248,7 @@ target_include_directories(firebase_app
     ${FIREBASE_GEN_FILE_DIR}
   PRIVATE
     ${FIREBASE_CPP_SDK_ROOT_DIR}
-    ${flatbuffers_SOURCE_DIR}/include
+    ${FLATBUFFERS_SOURCE_DIR}/include
 )
 target_compile_definitions(firebase_app
   PRIVATE
diff --git a/app/rest/CMakeLists.txt b/app/rest/CMakeLists.txt
@@ -42,11 +42,11 @@ add_library(firebase_rest_lib STATIC
 target_include_directories(firebase_rest_lib
   PUBLIC
     ${FIREBASE_CPP_SDK_ROOT_DIR}
-    ${flatbuffers_SOURCE_DIR}/include
-    ${zlib_SOURCE_DIR}/..
-    ${zlib_BINARY_DIR}
+    ${FLATBUFFERS_SOURCE_DIR}/include
+    ${ZLIB_SOURCE_DIR}/..
+    ${ZLIB_BINARY_DIR}
   PRIVATE
-    ${curl_SOURCE_DIR}/include
+    ${CURL_SOURCE_DIR}/include
 )
 
 if(MSVC)
diff --git a/auth/CMakeLists.txt b/auth/CMakeLists.txt
@@ -167,7 +167,7 @@ if(ANDROID OR IOS)
   set(additional_target_definitions)
 else()
   set(additional_include_DIR
-      ${flatbuffers_SOURCE_DIR}/include
+      ${FLATBUFFERS_SOURCE_DIR}/include
       ${LIBSECRET_INCLUDE_DIRS})
   set(additional_link_LIB
       firebase_rest_lib
diff --git a/cmake/external/curl.cmake b/cmake/external/curl.cmake
@@ -14,12 +14,10 @@
 
 include(ExternalProject)
 
-if(TARGET curl)
+if(TARGET curl OR NOT DOWNLOAD_CURL)
   return()
 endif()
 
-# TODO(b/117950963): Use a system- or user-supplied curl if available
-
 ExternalProject_Add(
   curl
 
@@ -32,4 +30,4 @@ ExternalProject_Add(
   BUILD_COMMAND ""
   INSTALL_COMMAND ""
   TEST_COMMAND ""
-)
+)
diff --git a/cmake/external/flatbuffers.cmake b/cmake/external/flatbuffers.cmake
@@ -14,7 +14,7 @@
 
 include(ExternalProject)
 
-if(TARGET flatbuffers)
+if(TARGET flatbuffers OR NOT DOWNLOAD_FLATBUFFERS)
   return()
 endif()
 
diff --git a/cmake/external/libuv.cmake b/cmake/external/libuv.cmake
@@ -14,12 +14,10 @@
 
 include(ExternalProject)
 
-if(TARGET libuv)
+if(TARGET libuv OR NOT DOWNLOAD_LIBUV)
   return()
 endif()
 
-# TODO(b/117950963): Use a system- or user-supplied libuv if available
-
 ExternalProject_Add(
   libuv
 
@@ -32,4 +30,4 @@ ExternalProject_Add(
   BUILD_COMMAND ""
   INSTALL_COMMAND ""
   TEST_COMMAND ""
-)
+)
diff --git a/cmake/external/nanopb.cmake b/cmake/external/nanopb.cmake
@@ -14,7 +14,7 @@
 
 include(ExternalProject)
 
-if(TARGET nanopb)
+if(TARGET nanopb OR NOT DOWNLOAD_NANOPB)
   return()
 endif()
 
@@ -31,4 +31,4 @@ ExternalProject_Add(
   BUILD_COMMAND ""
   INSTALL_COMMAND ""
   TEST_COMMAND ""
-)
+)
diff --git a/cmake/external/uWebSockets.cmake b/cmake/external/uWebSockets.cmake
@@ -14,12 +14,10 @@
 
 include(ExternalProject)
 
-if(TARGET uWebSockets)
+if(TARGET uWebSockets OR NOT DOWNLOAD_UWEBSOCKETS)
   return()
 endif()
 
-# TODO(b/117950963): Use a system- or user-supplied openssl if available
-
 ExternalProject_Add(
   uWebSockets
 
@@ -32,4 +30,4 @@ ExternalProject_Add(
   BUILD_COMMAND ""
   INSTALL_COMMAND ""
   TEST_COMMAND ""
-)
+)
diff --git a/cmake/external/zlib.cmake b/cmake/external/zlib.cmake
@@ -14,12 +14,10 @@
 
 include(ExternalProject)
 
-if(TARGET zlib)
+if(TARGET zlib OR NOT DOWNLOAD_ZLIB)
   return()
 endif()
 
-# TODO(b/117950963): Use a system- or user-supplied zlib if available
-
 ExternalProject_Add(
   zlib
 
@@ -34,4 +32,4 @@ ExternalProject_Add(
   BUILD_COMMAND ""
   INSTALL_COMMAND ""
   TEST_COMMAND ""
-)
+)
diff --git a/cmake/external_rules.cmake b/cmake/external_rules.cmake
@@ -36,13 +36,35 @@ function(download_external_sources)
   else()
     set(external_platform DESKTOP)
   endif()
-  
+
+  # Set variables to indicate if local versions of third party libraries should
+  # be used instead of downloading them.
+  function(check_use_local_directory NAME)
+    if (EXISTS ${${NAME}_SOURCE_DIR})
+      set(DOWNLOAD_${NAME} OFF PARENT_SCOPE)
+    else()
+      set(DOWNLOAD_${NAME} ON PARENT_SCOPE)
+    endif()
+  endfunction()
+  check_use_local_directory(CURL)
+  check_use_local_directory(FLATBUFFERS)
+  check_use_local_directory(LIBUV)
+  check_use_local_directory(NANOPB)
+  check_use_local_directory(UWEBSOCKETS)
+  check_use_local_directory(ZLIB)
+
   execute_process(
     COMMAND
       ${ENV_COMMAND} cmake
       -DCMAKE_INSTALL_PREFIX=${FIREBASE_INSTALL_DIR}
       -DFIREBASE_DOWNLOAD_DIR=${FIREBASE_DOWNLOAD_DIR}
       -DFIREBASE_EXTERNAL_PLATFORM=${external_platform}
+      -DDOWNLOAD_CURL=${DOWNLOAD_CURL}
+      -DDOWNLOAD_FLATBUFFERS=${DOWNLOAD_FLATBUFFERS}
+      -DDOWNLOAD_LIBUV=${DOWNLOAD_LIBUV}
+      -DDOWNLOAD_NANOPB=${DOWNLOAD_NANOPB}
+      -DDOWNLOAD_UWEBSOCKETS=${DOWNLOAD_UWEBSOCKETS}
+      -DDOWNLOAD_ZLIB=${DOWNLOAD_ZLIB}
       ${PROJECT_SOURCE_DIR}/cmake/external
     OUTPUT_FILE ${PROJECT_BINARY_DIR}/external/output_cmake_config.txt
     WORKING_DIRECTORY ${PROJECT_BINARY_DIR}/external
@@ -60,20 +82,24 @@ function(download_external_sources)
   )
 endfunction()
 
-# Populates directory variables for the given name, to the location that name
-# would be in after a call to download_external_sources.
-function(populate_external_source_vars NAME)
-  set(${NAME}_SOURCE_DIR "${FIREBASE_BINARY_DIR}/external/src/${NAME}"
-      PARENT_SCOPE)
-  set(${NAME}_BINARY_DIR "${FIREBASE_BINARY_DIR}/external/src/${NAME}-build"
-      PARENT_SCOPE)
-endfunction()
+# Populates directory variables for the given name to the location that name
+# would be in after a call to download_external_sources, if the variable is
+# not already a valid directory.
+# Adds the source directory as a subdirectory if a CMakeLists file is found.
+function(add_external_library NAME)
+  string(TOUPPER ${NAME} UPPER_NAME)
+  if (NOT EXISTS ${${UPPER_NAME}_SOURCE_DIR})
+    set(${UPPER_NAME}_SOURCE_DIR "${FIREBASE_BINARY_DIR}/external/src/${NAME}")
+    set(${UPPER_NAME}_SOURCE_DIR "${${UPPER_NAME}_SOURCE_DIR}" PARENT_SCOPE)
+  endif()
 
-# Adds the given library's location as a subdirectory that the caller uses.
-function(add_external_subdirectory NAME)
-  add_subdirectory(
-    ${FIREBASE_BINARY_DIR}/external/src/${NAME}
-    ${FIREBASE_BINARY_DIR}/external/src/${NAME}-build
-    EXCLUDE_FROM_ALL
-  )
-endfunction()
+  if (NOT EXISTS ${${UPPER_NAME}_BINARY_DIR})
+    set(${UPPER_NAME}_BINARY_DIR "${${UPPER_NAME}_SOURCE_DIR}-build")
+    set(${UPPER_NAME}_BINARY_DIR "${${UPPER_NAME}_BINARY_DIR}" PARENT_SCOPE)
+  endif()
+
+  if (EXISTS "${${UPPER_NAME}_SOURCE_DIR}/CMakeLists.txt")
+    add_subdirectory(${${UPPER_NAME}_SOURCE_DIR} ${${UPPER_NAME}_BINARY_DIR}
+                     EXCLUDE_FROM_ALL)
+  endif()
+endfunction()
diff --git a/database/CMakeLists.txt b/database/CMakeLists.txt
@@ -134,9 +134,9 @@ if(ANDROID OR IOS)
   set(additional_DEFINES)
 else()
   set(additional_include_DIR
-      ${flatbuffers_SOURCE_DIR}/include
+      ${FLATBUFFERS_SOURCE_DIR}/include
       ${OPENSSL_INCLUDE_DIR}
-      ${uWebSockets_SOURCE_DIR}/..)
+      ${UWEBSOCKETS_SOURCE_DIR}/..)
 
   set(additional_link_LIB
       flatbuffers
diff --git a/messaging/CMakeLists.txt b/messaging/CMakeLists.txt
@@ -97,7 +97,7 @@ target_include_directories(firebase_messaging
 if(ANDROID)
   target_include_directories(firebase_messaging
     PRIVATE
-      ${flatbuffers_SOURCE_DIR}/include
+      ${FLATBUFFERS_SOURCE_DIR}/include
   )
 endif()
 target_compile_definitions(firebase_messaging
diff --git a/remote_config/CMakeLists.txt b/remote_config/CMakeLists.txt
@@ -76,7 +76,7 @@ if(ANDROID OR IOS OR use_stub)
   set(additional_link_LIB)
 else()
   set(additional_include_DIR
-      ${flatbuffers_SOURCE_DIR}/include
+      ${FLATBUFFERS_SOURCE_DIR}/include
       ${NANOPB_INCLUDE_DIRS}
       ${PROJECT_BINARY_DIR}/..)
   set(additional_link_LIB

Original file line number	Diff line number	Diff line change
`@@ -248,7 +248,7 @@ target_include_directories(firebase_app`
`248`	`248`	`${FIREBASE_GEN_FILE_DIR}`
`249`	`249`	`PRIVATE`
`250`	`250`	`${FIREBASE_CPP_SDK_ROOT_DIR}`
`251`		`- ${flatbuffers_SOURCE_DIR}/include`
	`251`	`+ ${FLATBUFFERS_SOURCE_DIR}/include`
`252`	`252`	`)`
`253`	`253`	`target_compile_definitions(firebase_app`
`254`	`254`	`PRIVATE`