set mbed_set_error_hook() to deprecated

platform/mbed_error.h

@@ -940,6 +940,16 @@ MBED_NORETURN void error(const char *format, ...) MBED_PRINTF(1, 2);
  */
 #define MBED_MAKE_ERROR(module, error_code)                          MBED_MAKE_SYSTEM_ERROR(module, error_code)
 
+/**
+ * Callback/Error hook function prototype. Applications needing a callback when an error is reported can use mbed_set_error_hook function
+ * to register a callback/error hook function using the following prototype. When an error happens in the system error handling
+ * implementation will invoke this callback with the mbed_error_status_t reported and the error context at the time of error.
+ * @param  error_ctx        Error context structure associated with this error.
+ * @return                  void
+ *
+ */
+typedef void (*mbed_error_hook_t)(const mbed_error_ctx *error_ctx);
+
 /**
  * Callback/Error hook function. If application implementation needs to receive this callback when an error is reported, 
  * mbed_error_hook function should be overridden with custom implementation. When an error happens in the system error handling
@@ -950,7 +960,6 @@ MBED_NORETURN void error(const char *format, ...) MBED_PRINTF(1, 2);
  */
 void mbed_error_hook(const mbed_error_ctx *error_context);
 
-
 /**
  * Callback function for reporting error context during boot up. When MbedOS error handling system detects a fatal error
  * it will auto-reboot the system(if MBED_CONF_PLATFORM_FATAL_ERROR_AUTO_REBOOT_ENABLED is enabled) after capturing the
@@ -1070,6 +1079,30 @@ bool mbed_get_error_in_progress(void);
  */
 MBED_NORETURN mbed_error_status_t mbed_error(mbed_error_status_t error_status, const char *error_msg, unsigned int error_value, const char *filename, int line_number);
 
+/**
+ * Registers an application defined error callback with the error handling system.
+ * This function will be called with error context info whenever system handles a mbed_error/mbed_warning call
+ * NOTE: This function should be implemented for re-entrancy as multiple threads may invoke mbed_error which may cause error hook to be called.
+ * @param  custom_error_hook    mbed_error_status_t status to be set(See mbed_error_status_t enum above for available error status values).
+ * @return                      0 or MBED_SUCCESS on success.
+ *                              MBED_ERROR_INVALID_ARGUMENT in case of NULL for custom_error_hook
+ *
+ * @code
+ *
+ * mbed_error_status_t my_custom_error_hook(mbed_error_status_t error_status, const mbed_error_ctx *error_ctx) {
+ *    //Do something with the error_status or error_ctx
+ * }
+ *
+ * mbed_set_error_hook( my_custom_error_hook )
+ *
+ * @endcode
+ * @note The erro hook function implementation should be re-entrant.
+ * 
+ * @deprecated You should use an overridden mbed_error_hook() function if you like to catch errors in your application.
+ *             With mbed_set_error_hook() it is not possible to catch errors before your application started.
+ */
+mbed_error_status_t mbed_set_error_hook(mbed_error_hook_t custom_error_hook);
+
 /**
  * Reads the first error context information captured.
  * @param  error_info           This is the mbed_error_context info captured as part of the first mbed_error call. The caller should pass a pointer to mbed_error_context struct allocated by the caller.

platform/source/mbed_error.c

@@ -58,6 +58,7 @@ static int error_count = 0;
 static mbed_error_ctx first_error_ctx = {0};
 
 static mbed_error_ctx last_error_ctx = {0};
+static mbed_error_hook_t error_hook = NULL;
 static mbed_error_status_t handle_error(mbed_error_status_t error_status, unsigned int error_value, const char *filename, int line_number, void *caller);
 
 #if MBED_CONF_PLATFORM_CRASH_CAPTURE_ENABLED
@@ -193,8 +194,12 @@ static mbed_error_status_t handle_error(mbed_error_status_t error_status, unsign
     mbed_error_hist_put(&current_error_ctx);
 #endif
 
-     //Call the error hook
-    mbed_error_hook(&last_error_ctx);
+    //Call the error hook if available
+    if (error_hook != NULL) {
+        error_hook(&last_error_ctx);
+    } else { 
+        mbed_error_hook(&last_error_ctx);
+    }
 
     core_util_critical_section_exit();
 
@@ -324,6 +329,19 @@ WEAK MBED_NORETURN mbed_error_status_t mbed_error(mbed_error_status_t error_stat
     mbed_halt_system();
 }
 
+//Register an application defined callback with error handling
+MBED_DEPRECATED("Use an overridden mbed_error_hook() function")
+mbed_error_status_t mbed_set_error_hook(mbed_error_hook_t error_hook_in)
+{
+    //register the new hook/callback
+    if (error_hook_in != NULL) {
+        error_hook = error_hook_in;
+        return MBED_SUCCESS;
+    }
+
+    return MBED_ERROR_INVALID_ARGUMENT;
+}
+
 //Reset the reboot error context
 mbed_error_status_t mbed_reset_reboot_error_info()
 {