text: /*
   * This file is part of the Micro Python project, http://micropython.org/
   *
   * The MIT License (MIT)
   *
   * Copyright (c) 2015 Daniel Campora
   *
   * Permission is hereby granted, free of charge, to any person obtaining a copy
   * of this software and associated documentation files (the "Software"), to deal
   * in the Software without restriction, including without limitation the rights
   * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
   * copies of the Software, and to permit persons to whom the Software is
   * furnished to do so, subject to the following conditions:
   *
   * The above copyright notice and this permission notice shall be included in
   * all copies or substantial portions of the Software.
   *
   * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
   * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
   * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
   * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
   * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
   * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
   * THE SOFTWARE.
   */
  
  #include "std.h"
  
  #include "py/mpconfig.h"
  #include MICROPY_HAL_H
  #include "py/obj.h"
  #include "py/runtime.h"
  #include "py/gc.h"
  #include "inc/hw_types.h"
  #include "interrupt.h"
  #include "pybsleep.h"
  #include "mpcallback.h"
  #include "mpexception.h"
  #include "mperror.h"
  
  
  /******************************************************************************
   DEFINE PUBLIC DATA
   ******************************************************************************/
  const mp_arg_t mpcallback_init_args[] = {
      { MP_QSTR_mode,         MP_ARG_KW_ONLY | MP_ARG_INT, {.u_int = 0} },
      { MP_QSTR_handler,      MP_ARG_KW_ONLY | MP_ARG_OBJ, {.u_obj = mp_const_none} },
      { MP_QSTR_priority,     MP_ARG_KW_ONLY | MP_ARG_INT, {.u_int = 1} },
      { MP_QSTR_value,        MP_ARG_KW_ONLY | MP_ARG_INT, {.u_int = 0} },
      { MP_QSTR_wakes,        MP_ARG_KW_ONLY | MP_ARG_INT, {.u_int = PYB_PWR_MODE_ACTIVE} },
  };
  
  /******************************************************************************
   DEFINE PUBLIC FUNCTIONS
   ******************************************************************************/
  void mpcallback_init0 (void) {
      // initialize the callback objects list
      mp_obj_list_init(&MP_STATE_PORT(mpcallback_obj_list), 0);
  }
  
  mp_obj_t mpcallback_new (mp_obj_t parent, mp_obj_t handler, const mp_cb_methods_t *methods) {
      mpcallback_obj_t *self = m_new_obj(mpcallback_obj_t);
      self->base.type = &pyb_callback_type;
      self->handler = handler;
      self->parent = parent;
      self->methods = (mp_cb_methods_t *)methods;
      self->isenabled = true;
      // remove any old callback if present
      mpcallback_remove(self->parent);
      mp_obj_list_append(&MP_STATE_PORT(mpcallback_obj_list), self);
      return self;
  }
  
  mpcallback_obj_t *mpcallback_find (mp_obj_t parent) {
      for (mp_uint_t i = 0; i < MP_STATE_PORT(mpcallback_obj_list).len; i++) {
          mpcallback_obj_t *callback_obj = ((mpcallback_obj_t *)(MP_STATE_PORT(mpcallback_obj_list).items[i]));
          if (callback_obj->parent == parent) {
              return callback_obj;
          }
      }
      return NULL;
  }
  
  void mpcallback_wake_all (void) {
      // re-enable all active callback objects one by one
      for (mp_uint_t i = 0; i < MP_STATE_PORT(mpcallback_obj_list).len; i++) {
          mpcallback_obj_t *callback_obj = ((mpcallback_obj_t *)(MP_STATE_PORT(mpcallback_obj_list).items[i]));
          if (callback_obj->isenabled) {
              callback_obj->methods->enable(callback_obj->parent);
          }
      }
  }
  
  void mpcallback_remove (const mp_obj_t parent) {
      mpcallback_obj_t *callback_obj;
      if ((callback_obj = mpcallback_find(parent))) {
          mp_obj_list_remove(&MP_STATE_PORT(mpcallback_obj_list), callback_obj);
      }
  }
  
  uint mpcallback_translate_priority (uint priority) {
      if (priority < 1 || priority > 7) {
          nlr_raise(mp_obj_new_exception_msg(&mp_type_ValueError, mpexception_value_invalid_arguments));
      }
  
     switch (priority) {
     case 1:
         return INT_PRIORITY_LVL_7;
     case 2:
         return INT_PRIORITY_LVL_6;
     case 3:
         return INT_PRIORITY_LVL_5;
     case 4:
         return INT_PRIORITY_LVL_4;
     case 5:
         return INT_PRIORITY_LVL_3;
     case 6:
         return INT_PRIORITY_LVL_2;
     case 7:
         return INT_PRIORITY_LVL_1;
     default:
         return INT_PRIORITY_LVL_7;
     }
  }
  
  void mpcallback_handler (mp_obj_t self_in) {
      mpcallback_obj_t *self = self_in;
      if (self && self->handler != mp_const_none) {
          // when executing code within a handler we must lock the GC to prevent
          // any memory allocations.
          gc_lock();
          nlr_buf_t nlr;
          if (nlr_push(&nlr) == 0) {
              mp_call_function_1(self->handler, self->parent);
              nlr_pop();
          }
          else {
              // uncaught exception; disable the callback so that it doesn't run again
              self->methods->disable (self->parent);
              self->handler = mp_const_none;
              // signal the error using the heart beat led and print an
              // exception message as well
              mperror_signal_error();
              printf("Uncaught exception in callback handler\n");
              mp_obj_print_exception(&mp_plat_print, (mp_obj_t)nlr.ret_val);
          }
          gc_unlock();
      }
  }
  
  /******************************************************************************/
  // Micro Python bindings
  
  /// \method init()
  /// Initializes the interrupt callback. With no parameters passed, everything will default
  /// to the values assigned to mpcallback_init_args[].
  STATIC mp_obj_t callback_init(mp_uint_t n_args, const mp_obj_t *pos_args, mp_map_t *kw_args) {
      mpcallback_obj_t *self = pos_args[0];
      // this is a bit of a hack, but it let us reuse the callback_create method from our parent
      ((mp_obj_t *)pos_args)[0] = self->parent;
      self->methods->init (n_args, pos_args, kw_args);
      return mp_const_none;
  }
  MP_DEFINE_CONST_FUN_OBJ_KW(callback_init_obj, 1, callback_init);
  
  /// \method enable()
  /// Enables the interrupt callback
  STATIC mp_obj_t callback_enable (mp_obj_t self_in) {
      mpcallback_obj_t *self = self_in;
      self->methods->enable(self->parent);
      self->isenabled = true;
      return mp_const_none;
  }
  STATIC MP_DEFINE_CONST_FUN_OBJ_1(callback_enable_obj, callback_enable);
  
  /// \method disable()
  /// Disables the interrupt callback
  STATIC mp_obj_t callback_disable (mp_obj_t self_in) {
      mpcallback_obj_t *self = self_in;
      self->methods->disable(self->parent);
      self->isenabled = false;
      return mp_const_none;
  }
  STATIC MP_DEFINE_CONST_FUN_OBJ_1(callback_disable_obj, callback_disable);
  
  /// \method \call()
  /// Triggers the interrupt callback
  STATIC mp_obj_t callback_call(mp_obj_t self_in, mp_uint_t n_args, mp_uint_t n_kw, const mp_obj_t *args) {
      mp_arg_check_num(n_args, n_kw, 0, 0, false);
      mpcallback_handler (self_in);
      return mp_const_none;
  }
  
  STATIC const mp_map_elem_t callback_locals_dict_table[] = {
      // instance methods
      { MP_OBJ_NEW_QSTR(MP_QSTR_init),                (mp_obj_t)&callback_init_obj },
      { MP_OBJ_NEW_QSTR(MP_QSTR_enable),              (mp_obj_t)&callback_enable_obj },
      { MP_OBJ_NEW_QSTR(MP_QSTR_disable),             (mp_obj_t)&callback_disable_obj },
  };
  
  STATIC MP_DEFINE_CONST_DICT(callback_locals_dict, callback_locals_dict_table);
  
  const mp_obj_type_t pyb_callback_type = {
      { &mp_type_type },
      .name = MP_QSTR_callback,
      .call = callback_call,
      .locals_dict = (mp_obj_t)&callback_locals_dict,
  };
  
  