# ---[ RocksDB module # In addition to being a useful module itself, RocksDB is also an exemplar # case where show how one should built a Caffe2 module inside the Caffe2 # repository. # # This cmake file achieves two build modes: # (1) If one is invoking the main Caffe2 build, we will check a USE_* option, # in this case USE_ROCKSDB, to test if we want to build this module. # (2) if we are building it in a standalone way, we will find the preinstalled # Caffe2 library, and then build the library and install it. # ---[ First, determine if we are building with the main repo or not. # This is guarded by the CAFFE2_CMAKE_BUILDING_WITH_MAIN_REPO variable. It then # routes build to two paths: # (1) When we are building with the main repo, the caffe2_library is going to # be already defined, and all related paths will be defined too. So we will # simply test if the main repo build wants to build this module, in our # case by the variable "USE_ROCKSDB". # (2) When we are not building with the main repo, we will need to do the usual # cmake setup: version checks, project options, find dependent packages, # etc. if(CAFFE2_CMAKE_BUILDING_WITH_MAIN_REPO) if(NOT USE_ROCKSDB) return() endif() else() cmake_minimum_required(VERSION 3.0 FATAL_ERROR) project(caffe2_rocksdb CXX) find_package(Caffe2 REQUIRED) option(BUILD_SHARED_LIBS "Build shared libs." ON) list(APPEND CMAKE_MODULE_PATH ${CMAKE_CURRENT_LIST_DIR}/../../cmake/Modules) endif() # ---[ Second, find dependencies. # This one should be similar to the standard dependency discovery in normal # cmake. Note that for modules that are located in the Caffe2 repository, # cmake related files, such as FindRocksDB in this case, should live in the # cmake/ folder under root. find_package(RocksDB CONFIG) if((DEFINED RocksDB_DIR) AND RocksDB_DIR) list(APPEND RocksDB_LIBRARIES RocksDB::rocksdb) else() message("RocksDB config not found. Fallback to legacy find.") find_package(RocksDB) if(NOT ROCKSDB_FOUND) message( FATAL_ERROR "RocksDB not found. If you do not need caffe2_rocksdb, set " "-DUSE_ROCKSDB=OFF to solve this error.") endif() endif() # ---[ Third, create the CMake target. # The key to note is that this library will need to depend on caffe2_library, # which is the main lib of Caffe2. If your library explicitly depends on cuda, # then you will need to depend on the caffe2_gpu_library as well. add_library(caffe2_rocksdb ${CMAKE_CURRENT_SOURCE_DIR}/rocksdb.cc) # RocksDB 7 uses C++17 STL in header. if(RocksDB_VERSION_MAJOR VERSION_GREATER_EQUAL 7) set_target_properties(caffe2_rocksdb PROPERTIES CXX_STANDARD 17) endif() target_link_libraries(caffe2_rocksdb PUBLIC torch_library) target_link_libraries(caffe2_rocksdb PRIVATE ${RocksDB_LIBRARIES}) target_include_directories(caffe2_rocksdb PRIVATE ${RocksDB_INCLUDE_DIR}) install(TARGETS caffe2_rocksdb DESTINATION lib) # ---[ Last, Append the library to Caffe2_MODULES, if we are building with # the main repo. # The purpose of this is that, for all binaries built in the Caffe2 main repo, # they will be built with the first class modules that are built. As a result, # these binaries will not need to explicitly load these modules before using # them. # Note(jiayq): this also depends on a separate cmake move to reorg test builds # and binary builds after modules. When it is done, this note should be removed. if(CAFFE2_CMAKE_BUILDING_WITH_MAIN_REPO) set(Caffe2_MODULES ${Caffe2_MODULES} caffe2_rocksdb PARENT_SCOPE) endif()