Dev/shm free obsolete (#1274)

* freeing obsolete shm withoua a 'isValid' should access raw pointers. Need to move this all into the shm class

* fixed obsolete shm free issue

* minor

* ensuring the test works platform independent for size of int

slsDetectorSoftware/src/CtbConfig.h

@@ -3,7 +3,16 @@
 #include <vector>
 namespace sls {
 
+#define CTB_SHMAPIVERSION 0x250820
+#define CTB_SHMVERSION    0x250820
+
 class CtbConfig {
+  public:
+    /** fixed pattern */
+    int shmversion{CTB_SHMVERSION};
+    bool isValid{true}; // false if freed to block access from python or c++ api
+                        /** end of fixed pattern */
+  private:
     static constexpr size_t name_length = 20;
     static constexpr size_t num_dacs = 18;
     static constexpr size_t num_adcs = 32;
@@ -56,7 +65,6 @@ class CtbConfig {
     std::string getSlowADCName(size_t index) const;
     std::vector<std::string> getSlowADCNames() const;
     static const char *shm_tag();
-    bool isValid{true}; // false if freed to block access from python or c++ api
 };
 
 } // namespace sls

slsDetectorSoftware/src/Detector.cpp

@@ -30,7 +30,6 @@ void freeSharedMemory(const int detectorIndex, const int moduleIndex) {
         SharedMemory<sharedModule> moduleShm(detectorIndex, moduleIndex);
         if (moduleShm.exists()) {
             moduleShm.openSharedMemory(false);
-            moduleShm()->isValid = false;
             moduleShm.removeSharedMemory();
         }
         return;
@@ -43,7 +42,6 @@ void freeSharedMemory(const int detectorIndex, const int moduleIndex) {
     if (detectorShm.exists()) {
         detectorShm.openSharedMemory(false);
         numDetectors = detectorShm()->totalNumberOfModules;
-        detectorShm()->isValid = false;
         detectorShm.removeSharedMemory();
     }
 
@@ -51,16 +49,14 @@ void freeSharedMemory(const int detectorIndex, const int moduleIndex) {
         SharedMemory<sharedModule> moduleShm(detectorIndex, i);
         if (moduleShm.exists()) {
             moduleShm.openSharedMemory(false);
-            moduleShm()->isValid = false;
+            moduleShm.removeSharedMemory();
         }
-        moduleShm.removeSharedMemory();
     }
 
     // Ctb configuration
     SharedMemory<CtbConfig> ctbShm(detectorIndex, -1, CtbConfig::shm_tag());
     if (ctbShm.exists()) {
         ctbShm.openSharedMemory(false);
-        ctbShm()->isValid = false;
         ctbShm.removeSharedMemory();
     }
 }

slsDetectorSoftware/src/DetectorImpl.h

@@ -24,7 +24,7 @@ class detectorData;
 class Module;
 
 #define DETECTOR_SHMAPIVERSION 0x190809
-#define DETECTOR_SHMVERSION    0x250729
+#define DETECTOR_SHMVERSION    0x250820
 #define SHORT_STRING_LENGTH    50
 
 /**
@@ -51,17 +51,17 @@ struct sharedDetector {
     int totalNumberOfModules;
     slsDetectorDefs::detectorType detType;
 
-    bool isValid{true}; // false if freed to block access from python or c++ api
-
-    /** END OF FIXED PATTERN
-     * -----------------------------------------------*/
-
     /** Number of modules operated at once */
     slsDetectorDefs::xy numberOfModules;
 
     /**  max number of channels for complete detector*/
     slsDetectorDefs::xy numberOfChannels;
 
+    bool isValid{true}; // false if freed to block access from python or c++ api
+
+    /** END OF FIXED PATTERN
+     * -----------------------------------------------*/
+
     bool acquiringFlag;
     bool initialChecks;
     bool gapPixels;

slsDetectorSoftware/src/Module.h

@@ -19,7 +19,7 @@ namespace sls {
 class ServerInterface;
 
 #define MODULE_SHMAPIVERSION 0x190726
-#define MODULE_SHMVERSION    0x250729
+#define MODULE_SHMVERSION    0x250820
 
 /**
  * @short structure allocated in shared memory to store Module settings for

slsDetectorSoftware/src/SharedMemory.h

@@ -27,17 +27,25 @@
 
 namespace sls {
 
-struct sharedDetector;
+struct CtbConfig;
+// struct sharedDetector;
 
-#define SHM_DETECTOR_PREFIX "/slsDetectorPackage_detector_"
-#define SHM_MODULE_PREFIX   "_module_"
-#define SHM_ENV_NAME        "SLSDETNAME"
+#define SHM_IS_VALID_CHECK_VERSION 0x250820
+#define SHM_DETECTOR_PREFIX        "/slsDetectorPackage_detector_"
+#define SHM_MODULE_PREFIX          "_module_"
+#define SHM_ENV_NAME               "SLSDETNAME"
+
+template <typename T, typename U> constexpr bool is_type() {
+    return std::is_same_v<std::decay_t<U>, T>;
+}
 
 template <typename T> class SharedMemory {
 
+#ifndef DISABLE_STATIC_ASSERT
     static_assert(has_bool_isValid<T>::value,
                   "SharedMemory requires the struct to have a bool member "
                   "named 'isValid'");
+#endif
 
     static constexpr int NAME_MAX_LENGTH = 255;
     std::string name;
@@ -72,21 +80,49 @@ template <typename T> class SharedMemory {
             unmapSharedMemory();
     }
 
+    bool memoryHasValidFlag() const {
+        if constexpr (is_type<CtbConfig, T>()) {
+            // CtbConfig did not have shmversion before, so exact value check
+            if (shared_struct->shmversion == SHM_IS_VALID_CHECK_VERSION) {
+                return true;
+            }
+        } else if (shared_struct->shmversion >= SHM_IS_VALID_CHECK_VERSION) {
+            return true;
+        }
+        return false;
+    }
+
+    bool checkValidity() const {
+        if (memoryHasValidFlag() && !shared_struct->isValid)
+            return false;
+        return true;
+    }
+
+    void invalidate() {
+        // also called by obsolete shm test structure (so check added)
+        if constexpr (has_bool_isValid<T>::value) {
+            if (memoryHasValidFlag())
+                shared_struct->isValid = false;
+        }
+    }
+
     T *operator()() {
         if (!shared_struct)
             throw SharedMemoryError(getNoShmAccessMessage());
-        if (!shared_struct->isValid) {
+
+        if (!checkValidity())
             throw SharedMemoryError(getInvalidShmMessage());
-        }
+
         return shared_struct;
     }
 
     const T *operator()() const {
         if (!shared_struct)
             throw SharedMemoryError(getNoShmAccessMessage());
-        if (!shared_struct->isValid) {
+
+        if (!checkValidity())
             throw SharedMemoryError(getInvalidShmMessage());
-        }
+
         return shared_struct;
     }
 
@@ -146,6 +182,7 @@ template <typename T> class SharedMemory {
     }
 
     void removeSharedMemory() {
+        invalidate();
         unmapSharedMemory();
         if (shm_unlink(name.c_str()) < 0) {
             // silent exit if shm did not exist anyway