Allow building repository as CMake subdirectory (#2059)

* Use PROJECT_SOURCE_DIR rather than CMAKE_SOURCE_DIR to allow building as subdirectory

* Also use PROJECT_SOURCE_DIR instead of CMAKE_SOURCE_DIR in c/cxx api examples

* Only build examples by default when not building as subdirectory

* Do not suggest building binaries either

---------

Co-authored-by: user <user@mail.tld>

sherpa-onnx/c-api/CMakeLists.txt

@@ -1,6 +1,7 @@
-include_directories(${CMAKE_SOURCE_DIR})
+include_directories(${PROJECT_SOURCE_DIR})
 add_library(sherpa-onnx-c-api c-api.cc)
 target_link_libraries(sherpa-onnx-c-api sherpa-onnx-core)
+target_include_directories(sherpa-onnx-c-api PUBLIC ${PROJECT_SOURCE_DIR})
 
 if(BUILD_SHARED_LIBS)
   target_compile_definitions(sherpa-onnx-c-api PUBLIC SHERPA_ONNX_BUILD_SHARED_LIBS=1)
@@ -9,6 +10,7 @@ endif()
 
 add_library(sherpa-onnx-cxx-api cxx-api.cc)
 target_link_libraries(sherpa-onnx-cxx-api sherpa-onnx-c-api)
+target_include_directories(sherpa-onnx-cxx-api PUBLIC ${PROJECT_SOURCE_DIR})
 
 install(
   TARGETS

sherpa-onnx/csrc/CMakeLists.txt

@@ -1,4 +1,4 @@
-include_directories(${CMAKE_SOURCE_DIR})
+include_directories(${PROJECT_SOURCE_DIR})
 
 if(SHERPA_ONNX_ENABLE_PYTHON)
   message(STATUS "PYTHON_EXECUTABLE: ${PYTHON_EXECUTABLE}")
@@ -648,7 +648,7 @@ endforeach()
 # For clang-tidy
 add_custom_target(
   clang-tidy-check
-  clang-tidy -p ${CMAKE_BINARY_DIR}/compile_commands.json --config-file ${CMAKE_SOURCE_DIR}/.clang-tidy ${srcs_to_check}
+  clang-tidy -p ${CMAKE_BINARY_DIR}/compile_commands.json --config-file ${PROJECT_SOURCE_DIR}/.clang-tidy ${srcs_to_check}
   DEPENDS ${sources})
 
 add_custom_target(check DEPENDS clang-tidy-check)

sherpa-onnx/jni/CMakeLists.txt

@@ -1,4 +1,4 @@
-include_directories(${CMAKE_SOURCE_DIR})
+include_directories(${PROJECT_SOURCE_DIR})
 
 if(NOT DEFINED ANDROID_ABI)
   if(NOT DEFINED ENV{JAVA_HOME})

sherpa-onnx/python/csrc/CMakeLists.txt

@@ -1,4 +1,4 @@
-include_directories(${CMAKE_SOURCE_DIR})
+include_directories(${PROJECT_SOURCE_DIR})
 
 set(srcs
   audio-tagging.cc
@@ -51,7 +51,7 @@ set(srcs
   wave-writer.cc
 )
 if(SHERPA_ONNX_HAS_ALSA)
-  list(APPEND srcs ${CMAKE_SOURCE_DIR}/sherpa-onnx/csrc/alsa.cc alsa.cc)
+  list(APPEND srcs ${PROJECT_SOURCE_DIR}/sherpa-onnx/csrc/alsa.cc alsa.cc)
 else()
   list(APPEND srcs faked-alsa.cc)
 endif()