[clangd] WIP experimentation with finding static grpc++ libraries

[kbobyrev]

WIP, nothing important here.

clang-tools-extra/clangd/index/remote/server/CMakeLists.txt

 
 target_link_libraries(clangd-index-server
   PRIVATE
   clangDaemon
 
   RemoteIndexProtos
   clangdRemoteMarshalling
 
-  grpc++
+  /usr/local/google/home/kbobyrev/software/grpc-latest/lib/libgrpc++.a
+  /usr/local/google/home/kbobyrev/software/grpc-latest/lib/libgrpc.a
+  /usr/local/google/home/kbobyrev/software/grpc-latest/lib/libgrpc++_unsecure.a
+  /usr/local/google/home/kbobyrev/software/grpc-latest/lib/libgrpc_unsecure.a
   )

llvm/cmake/modules/FindGRPC.cmake

if (GRPC_INSTALL_PATH)
   set(GRPC_CPP_PLUGIN $<TARGET_FILE:gRPC::grpc_cpp_plugin>)
   set(PROTOC ${Protobuf_PROTOC_EXECUTABLE})
 else()
   find_program(GRPC_CPP_PLUGIN grpc_cpp_plugin)
   find_program(PROTOC protoc)
   if (GRPC_CPP_PLUGIN-NOTFOUND OR PROTOC-NOTFOUND)
     message(FATAL_ERROR "gRPC C++ Plugin and Protoc must be on $PATH for Clangd remote index build")
   endif()
+  if (${APPLE})
     # On macOS the libraries are typically installed via Homebrew and are not on
     # the system path.
-  if (${APPLE})
     find_program(HOMEBREW brew)
     # If Homebrew is not found, the user might have installed libraries
     # manually. Fall back to the system path.
     if (NOT HOMEBREW-NOTFOUND)
       execute_process(COMMAND ${HOMEBREW} --prefix grpc
         OUTPUT_VARIABLE GRPC_HOMEBREW_PATH
         RESULT_VARIABLE GRPC_HOMEBREW_RETURN_CODE
         OUTPUT_STRIP_TRAILING_WHITESPACE)
if (NOT HOMEBREW-NOTFOUND)
                      PATHS ${PROTOBUF_HOMEBREW_PATH}/lib
                      NO_DEFAULT_PATH
                      REQUIRED)
         add_library(protobuf UNKNOWN IMPORTED GLOBAL)
         set_target_properties(protobuf PROPERTIES
                               IMPORTED_LOCATION ${PROTOBUF_LIBRARY})
       endif()
     endif()
+  elseif(${UNIX} AND NOT BUILD_SHARED_LIBS)
+    # Use dpkg on Debian-like Linux distributions to find static libraries.
+    find_program(DPKG dpkg)
+    if (NOT DPKG-NOTFOUND)
+      execute_process(COMMAND ${DPKG} -L libgrpc++-dev
+        OUTPUT_VARIABLE GRPC_DPKG_PATHS
+        RESULT_VARIABLE GRPC_DPKG_RETURN_CODE
+        OUTPUT_STRIP_TRAILING_WHITESPACE)
+      if (GRPC_DPKG_RETURN_CODE EQUAL "0")
+        # Split the output into CMake list.
+        string(REPLACE "\n" ";" GRPC_DPKG_LINES ${GRPC_DPKG_PATHS})
+        foreach(GRPC_PATH ${GRPC_DPKG_LINES})
+          string(FIND ${GRPC_PATH} "libgrpc++.a" LIBGRPCPP_SUBSTR_IDX)
+          if (NOT LIBGRPCPP_SUBSTR_IDX EQUAL "-1")
+            add_library(grpc++ STATIC IMPORTED GLOBAL)
+            set_target_properties(grpc++ PROPERTIES
+                                  IMPORTED_LOCATION ${GRPC_PATH})
+            message("grpc++ lib ${GRPC_PATH}")
+          endif()
+          string(FIND ${GRPC_PATH} "libgrpc++_unsecure.a" LIBGRRPC_UNSECURE_SUBSTR_IDX)
+          if (NOT LIBGRRPC_UNSECURE_SUBSTR_IDX EQUAL "-1")
+            add_library(libgrpc++_unsecure STATIC IMPORTED GLOBAL)
+            set_target_properties(libgrpc++_unsecure PROPERTIES
+                                  IMPORTED_LOCATION ${GRPC_PATH})
+            message("grpc+++_unsecure lib ${GRPC_PATH}")
+          endif()
+        endforeach()
+      endif()
+      execute_process(COMMAND ${DPKG} -L libprotobuf-dev
+        OUTPUT_VARIABLE PROTOBUF_DPKG_PATHS
+        RESULT_VARIABLE PROTOBUF_DPKG_RETURN_CODE
+        OUTPUT_STRIP_TRAILING_WHITESPACE)
+      if (PROTOBUF_DPKG_RETURN_CODE EQUAL "0")
+        # Split the output into CMake list.
+        string(REPLACE "\n" ";" PROTOBUF_DPKG_LINES ${PROTOBUF_DPKG_PATHS})
+        foreach(PROTOBUF_PATH ${PROTOBUF_DPKG_LINES})
+          string(FIND ${PROTOBUF_PATH} "libprotobuf.a" LIBPROTOBUF_SUBSTR_IDX)
+          if (NOT LIBPROTOBUF_SUBSTR_IDX EQUAL "-1")
+            add_library(protobuf STATIC IMPORTED GLOBAL)
+            set_target_properties(protobuf PROPERTIES
+                                  IMPORTED_LOCATION ${PROTOBUF_PATH})
+          endif()
+        endforeach()
+      endif()
+    endif()
   endif()
 endif()
 
 # Proto headers are generated in ${CMAKE_CURRENT_BINARY_DIR}.
 # Libraries that use these headers should adjust the include path.
 # FIXME(kirillbobyrev): Allow optional generation of gRPC code and give callers
 # control over it via additional parameters.
 function(generate_grpc_protos LibraryName ProtoFile)