Use add_custom_command instead of execute_process for building protos.
This more closely matches how CMake is supposed to be used. It adds the
commands as build steps instead of running them as part of analyzing the
build script itself. This allows the build steps to be parallelized,
produce output in the correct place, and run only when libicing is
actually being built.
Bug: 149853706
Test: ./gradlew external:icing:assemble
Change-Id: I548cf82d5d5ed6377fd65fa8f5ed04e90bd0d4f8
diff --git a/CMakeLists.txt b/CMakeLists.txt
index f41890a..398b35e 100644
--- a/CMakeLists.txt
+++ b/CMakeLists.txt
@@ -26,31 +26,23 @@
set(Protobuf_SOURCE_DIR "${CMAKE_CURRENT_SOURCE_DIR}/../protobuf")
set(Protobuf_HOST_BINARY_DIR "${CMAKE_CURRENT_BINARY_DIR}/protobuf-host")
set(Protobuf_TARGET_BINARY_DIR "${CMAKE_CURRENT_BINARY_DIR}/protobuf-target")
+add_custom_command(
+ OUTPUT "${Protobuf_HOST_BINARY_DIR}/protoc"
-# Run another cmake invocation to configure the protobuf project
-execute_process(
+ # Run another cmake invocation to configure the protobuf project
COMMAND "${CMAKE_COMMAND}"
- ${CMAKE_HOST_ARGS}
- -H${Protobuf_SOURCE_DIR}/cmake
- -B${Protobuf_HOST_BINARY_DIR}
- -Dprotobuf_BUILD_TESTS:BOOL=OFF
- RESULT_VARIABLE exec_value
- OUTPUT_VARIABLE exec_output
- ERROR_VARIABLE exec_output
-)
-message("Result of proto configuration: ${exec_value}. Output: ${exec_output}")
+ ${CMAKE_HOST_ARGS}
+ -H${Protobuf_SOURCE_DIR}/cmake
+ -B${Protobuf_HOST_BINARY_DIR}
+ -Dprotobuf_BUILD_TESTS:BOOL=OFF
-# Run the actual build tool (ninja) to compile protoc for the host
-execute_process(
+ # Run the actual build tool (ninja) to compile protoc for the host
COMMAND "${CMAKE_MAKE_PROGRAM}" protoc
WORKING_DIRECTORY ${Protobuf_HOST_BINARY_DIR}
- RESULT_VARIABLE exec_value
- OUTPUT_VARIABLE exec_output
- ERROR_VARIABLE exec_output
)
-message("Result of proto build: ${exec_value}. Output: ${exec_output}")
+message(STATUS "Building protoc at: ${Protobuf_HOST_BINARY_DIR}/protoc")
-# Glob Icing proto sources
+# Glob Icing proto sources. Results look like this: icing/proto/document.proto
file(
GLOB_RECURSE
Icing_PROTO_FILES
@@ -64,26 +56,20 @@
foreach(FILE ${Icing_PROTO_FILES})
# Find the name of the proto file without the .proto extension
string(REGEX REPLACE "\.proto$" "" FILE_NOEXT ${FILE})
- execute_process(
+ list(APPEND Icing_PROTO_SOURCES
+ "${Icing_PROTO_GEN_DIR}/${FILE_NOEXT}.pb.cc"
+ "${Icing_PROTO_GEN_DIR}/${FILE_NOEXT}.pb.h")
+ add_custom_command(
+ OUTPUT "${Icing_PROTO_GEN_DIR}/${FILE_NOEXT}.pb.cc"
+ "${Icing_PROTO_GEN_DIR}/${FILE_NOEXT}.pb.h"
COMMAND "${Protobuf_HOST_BINARY_DIR}/protoc"
- --proto_path ${CMAKE_CURRENT_SOURCE_DIR}
- --cpp_out ${Icing_PROTO_GEN_DIR}
- ${FILE}
+ --proto_path ${CMAKE_CURRENT_SOURCE_DIR}
+ --cpp_out ${Icing_PROTO_GEN_DIR}
+ ${FILE}
WORKING_DIRECTORY ${CMAKE_CURRENT_SOURCE_DIR}
- RESULT_VARIABLE exec_value
- OUTPUT_VARIABLE exec_output
- ERROR_VARIABLE exec_output
+ DEPENDS "${Protobuf_HOST_BINARY_DIR}/protoc"
)
- message("Result of protoc ${FILE}: ${exec_value}. Output: ${exec_output}")
endforeach()
-
-# Glob generated source files from running protoc
-file(
- GLOB_RECURSE
- Icing_PROTO_SOURCES
- "${Icing_PROTO_GEN_DIR}/*.pb.cc"
- "${Icing_PROTO_GEN_DIR}/*.pb.h"
-)
message(STATUS "Icing_PROTO_SOURCES=${Icing_PROTO_SOURCES}")
# Compile libprotobuf