add WebAssembly for Kws (#648)

wasm/kws/CMakeLists.txt

@@ -0,0 +1,54 @@
+if(NOT $ENV{SHERPA_ONNX_IS_USING_BUILD_WASM_SH})
+    message(FATAL_ERROR "Please use ./build-wasm-simd-kws.sh to build for wasm KWS")
+endif()
+
+if(NOT EXISTS "${CMAKE_CURRENT_SOURCE_DIR}/assets/decoder-epoch-12-avg-2-chunk-16-left-64.onnx")
+    message(WARNING "${CMAKE_CURRENT_SOURCE_DIR}/assets/decoder-epoch-12-avg-2-chunk-16-left-64.onnx does not exist")
+    message(FATAL_ERROR "Please read ${CMAKE_CURRENT_SOURCE_DIR}/assets/README.md before you continue")
+endif()
+
+set(exported_functions
+        AcceptWaveform
+        CreateKeywordSpotter
+        DestroyKeywordSpotter
+        CreateKeywordStream
+        DecodeKeywordStream
+        GetKeywordResult
+        DestroyKeywordResult
+        IsKeywordStreamReady
+        InputFinished
+)
+set(mangled_exported_functions)
+foreach(x IN LISTS exported_functions)
+    list(APPEND mangled_exported_functions "_${x}")
+endforeach()
+
+list(JOIN mangled_exported_functions "," all_exported_functions)
+
+include_directories(${CMAKE_SOURCE_DIR})
+set(MY_FLAGS "-s FORCE_FILESYSTEM=1 -s INITIAL_MEMORY=512MB -s ALLOW_MEMORY_GROWTH=1")
+string(APPEND MY_FLAGS " -sSTACK_SIZE=10485760 ")
+string(APPEND MY_FLAGS " -sEXPORTED_FUNCTIONS=[_CopyHeap,_malloc,_free,${all_exported_functions}] ")
+string(APPEND MY_FLAGS "--preload-file ${CMAKE_CURRENT_SOURCE_DIR}/assets@. ")
+string(APPEND MY_FLAGS " -sEXPORTED_RUNTIME_METHODS=['ccall','stringToUTF8','setValue','getValue','lengthBytesUTF8','UTF8ToString'] ")
+message(STATUS "MY_FLAGS: ${MY_FLAGS}")
+
+set(CMAKE_C_FLAGS "${CMAKE_C_FLAGS} ${MY_FLAGS}")
+set(CMAKE_CXX_FLAGS "${CMAKE_CXX_FLAGS} ${MY_FLAGS}")
+set(CMAKE_EXECUTBLE_LINKER_FLAGS "${CMAKE_EXECUTBLE_LINKER_FLAGS} ${MY_FLAGS}")
+
+add_executable(sherpa-onnx-wasm-kws-main sherpa-onnx-wasm-main-kws.cc)
+target_link_libraries(sherpa-onnx-wasm-kws-main sherpa-onnx-c-api)
+install(TARGETS sherpa-onnx-wasm-kws-main DESTINATION bin/wasm)
+
+install(
+        FILES
+        "sherpa-onnx-kws.js"
+        "app.js"
+        "index.html"
+        "$<TARGET_FILE_DIR:sherpa-onnx-wasm-kws-main>/sherpa-onnx-wasm-kws-main.js"
+        "$<TARGET_FILE_DIR:sherpa-onnx-wasm-kws-main>/sherpa-onnx-wasm-kws-main.wasm"
+        "$<TARGET_FILE_DIR:sherpa-onnx-wasm-kws-main>/sherpa-onnx-wasm-kws-main.data"
+        DESTINATION
+        bin/wasm
+)