Add MPFBreaker

CMakeLists.txt

@@ -60,6 +60,9 @@ function(export_mpf_lib targetName)
     install(EXPORT ${targetName}Config DESTINATION lib/cmake/${targetName} EXPORT_LINK_INTERFACE_LIBRARIES)
 endfunction()
 
+add_subdirectory(internal)
+include_directories(internal/include)
+
 add_subdirectory(interface)
 include_directories(interface/include)
 

detection/api/CMakeLists.txt

@@ -109,12 +109,12 @@ set(SOURCE_FILES
     )
 
 add_library(mpfDetectionComponentApi SHARED ${SOURCE_FILES})
-target_link_libraries(mpfDetectionComponentApi mpfComponentInterface ${OpenCV_LIBS})
-
 
+target_link_libraries(
+    mpfDetectionComponentApi
+    PUBLIC mpfComponentInterface ${OpenCV_LIBS}
+    PRIVATE mpfInternalObjLib)
 
 export_mpf_lib(mpfDetectionComponentApi)
 
-
 add_subdirectory(test)
-

detection/api/src/MPFVideoCapture.cpp

@@ -36,6 +36,7 @@
 #include "IntervalFrameFilter.h"
 #include "KeyFrameFilter.h"
 #include "MPFDetectionException.h"
+#include "MPFBreaker.h"
 
 #include "MPFVideoCapture.h"
 
@@ -207,6 +208,7 @@ namespace MPF { namespace COMPONENT {
 
 
     bool MPFVideoCapture::Read(cv::Mat &frame) {
+        MPFBreaker::check();
         int originalPosBeforeRead = framePosition_;
         if (frameFilter_->IsPastEndOfSegment(originalPosBeforeRead)) {
             frame.release();

internal/CMakeLists.txt

@@ -0,0 +1,48 @@
+#############################################################################
+# NOTICE                                                                    #
+#                                                                           #
+# This software (or technical data) was produced for the U.S. Government    #
+# under contract, and is subject to the Rights in Data-General Clause       #
+# 52.227-14, Alt. IV (DEC 2007).                                            #
+#                                                                           #
+# Copyright 2026 The MITRE Corporation. All Rights Reserved.                #
+#############################################################################
+
+#############################################################################
+# Copyright 2026 The MITRE Corporation                                      #
+#                                                                           #
+# 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                                   #
+#                                                                           #
+#    http://www.apache.org/licenses/LICENSE-2.0                             #
+#                                                                           #
+# 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.                                            #
+#############################################################################
+
+cmake_minimum_required(VERSION 3.6)
+project(openmpf-internal)
+
+set(CMAKE_CXX_STANDARD 17)
+
+include_directories(include)
+
+set(SOURCE_FILES
+        include/MPFBreaker.h
+        src/MPFBreaker.cpp)
+
+add_library(mpfInternalObjLib OBJECT ${SOURCE_FILES})
+
+# Position-independent code is required because MPFBreaker uses a global variable that should be
+# shared with any library linking to this one.
+set_target_properties(mpfInternalObjLib PROPERTIES
+        INTERFACE_POSITION_INDEPENDENT_CODE ON
+        POSITION_INDEPENDENT_CODE ON)
+
+add_library(mpfInternal SHARED $<TARGET_OBJECTS:mpfInternalObjLib>)
+
+export_mpf_lib(mpfInternal)

internal/include/MPFBreaker.h

@@ -0,0 +1,44 @@
+/******************************************************************************
+ * NOTICE                                                                     *
+ *                                                                            *
+ * This software (or technical data) was produced for the U.S. Government     *
+ * under contract, and is subject to the Rights in Data-General Clause        *
+ * 52.227-14, Alt. IV (DEC 2007).                                             *
+ *                                                                            *
+ * Copyright 2026 The MITRE Corporation. All Rights Reserved.                 *
+ ******************************************************************************/
+
+/******************************************************************************
+ * Copyright 2026 The MITRE Corporation                                       *
+ *                                                                            *
+ * 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                                    *
+ *                                                                            *
+ *    http://www.apache.org/licenses/LICENSE-2.0                              *
+ *                                                                            *
+ * 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.                                             *
+ ******************************************************************************/
+
+#pragma once
+
+#include <stdexcept>
+
+namespace MPF::COMPONENT {
+
+    class StopRequestedException : public std::runtime_error {
+    public:
+        using std::runtime_error::runtime_error;
+    };
+
+
+    namespace MPFBreaker {
+        void requestStop();
+
+        void check();
+    }
+} // namespace MPF::COMPONENT

internal/src/MPFBreaker.cpp

@@ -0,0 +1,74 @@
+/******************************************************************************
+ * NOTICE                                                                     *
+ *                                                                            *
+ * This software (or technical data) was produced for the U.S. Government     *
+ * under contract, and is subject to the Rights in Data-General Clause        *
+ * 52.227-14, Alt. IV (DEC 2007).                                             *
+ *                                                                            *
+ * Copyright 2026 The MITRE Corporation. All Rights Reserved.                 *
+ ******************************************************************************/
+
+/******************************************************************************
+ * Copyright 2026 The MITRE Corporation                                       *
+ *                                                                            *
+ * 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                                    *
+ *                                                                            *
+ *    http://www.apache.org/licenses/LICENSE-2.0                              *
+ *                                                                            *
+ * 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 "MPFBreaker.h"
+
+#include <atomic>
+#include <iostream>
+#include <string>
+#include <exception>
+
+namespace MPF::COMPONENT {
+    namespace {
+        std::atomic<bool> STOP_REQUESTED{false};
+    }
+
+
+    void MPFBreaker::requestStop() {
+        std::cerr << "MPFBreaker: Setting stop requested flag to true.\n";
+        STOP_REQUESTED.store(true, std::memory_order::memory_order_release);
+    }
+
+
+    void MPFBreaker::check() {
+        if (!STOP_REQUESTED.load(std::memory_order::memory_order_acquire)) {
+            return;
+        }
+
+        std::cerr << "MPFBreaker: The stop requested flag was set to true. "
+            "Throwing StopRequestedException.\n";
+        auto e_ptr = std::current_exception();
+        if (!e_ptr) {
+            throw StopRequestedException{"Stop requested."};
+        }
+
+        try {
+            std::rethrow_exception(e_ptr);
+        }
+        catch (const StopRequestedException&) {
+            throw;
+        }
+        catch (const std::exception& e) {
+            throw StopRequestedException{
+                std::string{"Stop requested. Suppressed the following exception: "}
+                + e.what()};
+        }
+        catch (...) {
+            throw StopRequestedException{
+                "Stop requested. Suppressed a thrown non-exception object."};
+        }
+    }
+} // namespace MPF::COMPONENT