panic: user callback for common error handler

components/esp32/Kconfig

@@ -511,6 +511,14 @@ config ESP32_PANIC_GDBSTUB
         of the crash.
 endchoice
 
+config ESP32_PANIC_CALLBACK
+    bool "Support registration of a user defined callback for the panic handler"
+    default y
+    help
+        Use xt_set_error_handler_callback() to register a custom callback.
+        The callback is called by the common error handler so catches exceptions,
+        panics and abort() calls.
+
 config ESP32_DEBUG_OCDAWARE
     bool "Make exception and panic handlers JTAG/OCD aware"
     default y
@@ -518,7 +526,6 @@ config ESP32_DEBUG_OCDAWARE
         The FreeRTOS panic and unhandled exception handers can detect a JTAG OCD debugger and
         instead of panicking, have the debugger stop on the offending instruction.
 
-
 config INT_WDT
     bool "Interrupt watchdog"
     default y

components/esp32/panic.c

@@ -518,6 +518,19 @@ static void commonErrorHandler_dump(XtExcFrame *frame, int core_id)
 
 }
 
+#if CONFIG_ESP32_PANIC_CALLBACK
+/*
+ * Custom error handler callback registration.
+ */
+xt_error_handler_callback customErrorHandler = NULL;
+xt_error_handler_callback xt_set_error_handler_callback(xt_error_handler_callback f)
+{
+  xt_error_handler_callback old = customErrorHandler;
+  customErrorHandler = f;
+  return old;
+}
+#endif //CONFIG_ESP32_PANIC_CALLBACK
+
 /*
   We arrive here after a panic or unhandled exception, when no OCD is detected. Dump the registers to the
   serial port and either jump to the gdb stub, halt the CPU or reboot.
@@ -539,6 +552,14 @@ static __attribute__((noreturn)) void commonErrorHandler(XtExcFrame *frame)
     }
 #endif //!CONFIG_FREERTOS_UNICORE
 
+#if CONFIG_ESP32_PANIC_CALLBACK
+  if (customErrorHandler) {
+    disableAllWdts();
+    customErrorHandler(frame, core_id, abort_called);
+    reconfigureAllWdts();
+  }
+#endif
+
 #if CONFIG_ESP32_APPTRACE_ENABLE
     disableAllWdts();
 #if CONFIG_SYSVIEW_ENABLE

components/freertos/include/freertos/xtensa_api.h

@@ -39,6 +39,9 @@ typedef void (*xt_handler)(void *);
 /* Typedef for C-callable exception handler function */
 typedef void (*xt_exc_handler)(XtExcFrame *);
 
+/* Typedef for C-callable standard error handler callback */
+typedef void (*xt_error_handler_callback)(XtExcFrame *, int core_id, bool is_abort);
+
 
 /*
 -------------------------------------------------------------------------------
@@ -60,6 +63,23 @@ typedef void (*xt_exc_handler)(XtExcFrame *);
 extern xt_exc_handler xt_set_exception_handler(int n, xt_exc_handler f);
 
 
+/*
+-------------------------------------------------------------------------------
+  Call this function to set a callback for the standard error handler.
+  The callback will be called by the commonErrorHandler on all errors.
+
+    f        - Callback function address, NULL to uninstall callback.
+
+  The callback will be passed a pointer to the exception frame, which is created
+  on the stack of the thread that caused the exception, the core id and
+  a bool to signal if abort() has been called.
+
+  The callback is called with watchdogs disabled.
+-------------------------------------------------------------------------------
+*/
+extern xt_error_handler_callback xt_set_error_handler_callback(xt_error_handler_callback f);
+
+
 /*
 -------------------------------------------------------------------------------
   Call this function to set a handler for the specified interrupt. The handler