test(itk-wasm): add pthreads and cxx-threads test pipelines

packages/core/typescript/itk-wasm/test/pipelines/CMakeLists.txt

@@ -8,4 +8,8 @@ add_subdirectory("median-filter-pipeline")
 add_subdirectory("mesh-read-write-pipeline")
 add_subdirectory("transform-read-write-pipeline")
 add_subdirectory("read-image")
-add_subdirectory("stdout-stderr-pipeline")
+add_subdirectory("stdout-stderr-pipeline")
+if (NOT EMSCRIPTEN)
+  add_subdirectory("pthreads-pipeline")
+  add_subdirectory("cxx-threads-pipeline")
+endif()

packages/core/typescript/itk-wasm/test/pipelines/cxx-threads-pipeline/CMakeLists.txt

@@ -0,0 +1,16 @@
+cmake_minimum_required(VERSION 3.16)
+project(cxx-threads-test)
+
+set(CMAKE_CXX_STANDARD 20)
+
+find_package(ITK REQUIRED
+  COMPONENTS WebAssemblyInterface)
+include(${ITK_USE_FILE})
+add_executable(cxx-threads-test cxx-threads-test.cxx)
+target_link_libraries(cxx-threads-test PUBLIC WebAssemblyInterface)
+
+enable_testing()
+add_test(NAME CjXThreadsTest
+  COMMAND cxx-threads-test
+    ${CMAKE_CURRENT_BINARY_DIR}/cxx-threads-test-output.json
+  )

packages/core/typescript/itk-wasm/test/pipelines/cxx-threads-pipeline/cxx-threads-test.cxx

@@ -0,0 +1,61 @@
+/*=========================================================================
+ *
+ *  Copyright NumFOCUS
+ *
+ *  Licensed under the Apache License, Version 2.0 (the "License");
+ *  you may not use this file except in compliance with the License.
+ *  You may obtain a copy of the License at
+ *
+ *         https://www.apache.org/licenses/LICENSE-2.0.txt
+ *
+ *  Unless required by applicable law or agreed to in writing, software
+ *  distributed under the License is distributed on an "AS IS" BASIS,
+ *  WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ *  See the License for the specific language governing permissions and
+ *  limitations under the License.
+ *
+ *=========================================================================*/
+#include "itkPipeline.h"
+#include "itkOutputTextStream.h"
+
+#include <sstream>
+#include <iostream>
+#include <atomic>
+#include <thread>
+#include <vector>
+
+static std::atomic<int> createdThreads(0);
+
+int main(int argc, char * argv[])
+{
+  itk::wasm::Pipeline pipeline("cxx-threads-test", "A pipeline to test C++11 threads support", argc, argv);
+
+  int numberOfThreads = 4;
+  pipeline.add_option("-n,--number-of-threads", numberOfThreads, "The number of threads to use");
+
+  itk::wasm::OutputTextStream outputJson;
+  pipeline.add_option("output-json", outputJson, "The output json with test results")->type_name("OUTPUT_JSON");
+
+  ITK_WASM_PARSE(pipeline);
+
+  std::vector<std::thread> threads;
+  threads.reserve(numberOfThreads);
+  createdThreads = 0;
+
+  for (int i = 0; i < numberOfThreads; ++i)
+  {
+    threads.emplace_back([i]()
+    {
+      std::cout << " in thread " << i << std::endl;
+      createdThreads++;
+    });
+  }
+
+  for (auto &t : threads)
+  {
+    t.join();
+  }
+
+  outputJson.Get() << "{ \"createdThreads\": " << createdThreads << " }" << std::endl;
+  return EXIT_SUCCESS;
+}

packages/core/typescript/itk-wasm/test/pipelines/pthreads-pipeline/CMakeLists.txt

@@ -0,0 +1,16 @@
+cmake_minimum_required(VERSION 3.16)
+project(pthreads-test)
+
+set(CMAKE_CXX_STANDARD 20)
+
+find_package(ITK REQUIRED
+  COMPONENTS WebAssemblyInterface)
+include(${ITK_USE_FILE})
+add_executable(pthreads-test pthreads-test.cxx)
+target_link_libraries(pthreads-test PUBLIC WebAssemblyInterface)
+
+enable_testing()
+add_test(NAME PThreadsTest
+  COMMAND pthreads-test
+    ${CMAKE_CURRENT_BINARY_DIR}/pthreads-test-output.json
+  )

packages/core/typescript/itk-wasm/test/pipelines/pthreads-pipeline/pthreads-test.cxx

@@ -0,0 +1,68 @@
+/*=========================================================================
+ *
+ *  Copyright NumFOCUS
+ *
+ *  Licensed under the Apache License, Version 2.0 (the "License");
+ *  you may not use this file except in compliance with the License.
+ *  You may obtain a copy of the License at
+ *
+ *         https://www.apache.org/licenses/LICENSE-2.0.txt
+ *
+ *  Unless required by applicable law or agreed to in writing, software
+ *  distributed under the License is distributed on an "AS IS" BASIS,
+ *  WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ *  See the License for the specific language governing permissions and
+ *  limitations under the License.
+ *
+ *=========================================================================*/
+#include "itkPipeline.h"
+#include "itkOutputTextStream.h"
+
+#include <sstream>
+#include <iostream>
+#include <atomic>
+
+#include "pthread.h"
+
+static std::atomic<int> createdThreads(0);
+
+void *thread_entry_point(void *ctx) {
+  int id = (int) ctx;
+  printf(" in thread %d\n", id);
+  createdThreads++;
+  return 0;
+}
+
+int main( int argc, char * argv[] )
+{
+  itk::wasm::Pipeline pipeline("pthreads-test", "A pipeline to test pthreads support", argc, argv);
+
+  int numberOfThreads = 4;
+  pipeline.add_option("-n,--number-of-threads", numberOfThreads, "The number of threads to use");
+
+  itk::wasm::OutputTextStream outputJson;
+  pipeline.add_option("output-json", outputJson, "The output json with test results")->type_name("OUTPUT_JSON");
+
+  ITK_WASM_PARSE(pipeline);
+
+  // Based on: https://bytecodealliance.org/articles/wasi-threads
+  pthread_t threads[256];
+  createdThreads = 0;
+  for (int i = 0; i < numberOfThreads; i++) {
+    int ret = pthread_create(&threads[i], NULL, &thread_entry_point, (void *) i);
+    if (ret) {
+      printf("failed to spawn thread: %s", strerror(ret));
+    }
+  }
+
+  // Wait for all threads to finish
+  for (int i = 0; i < numberOfThreads; i++)
+  {
+    pthread_join(threads[i], NULL);
+  }
+
+  // Write the output JSON
+  outputJson.Get() << "{ \"createdThreads\": " << createdThreads << " }" << std::endl;
+
+  return EXIT_SUCCESS;
+}