1 /* 2 * Copyright (c) 2020 Endian Technologies AB 3 * 4 * SPDX-License-Identifier: Apache-2.0 5 */ 6 7 #ifndef ZEPHYR_INCLUDE_NET_LWM2M_PATH_H_ 8 #define ZEPHYR_INCLUDE_NET_LWM2M_PATH_H_ 9 10 /** 11 * @brief LwM2M path helper macros 12 * @defgroup lwm2m_path_helpers LwM2M path helper macros 13 * @ingroup lwm2m_api 14 * @{ 15 */ 16 17 /** 18 * @brief Generate LwM2M string paths using numeric components. 19 * 20 * Accepts at least one and up to four arguments. Each argument will be 21 * stringified by the pre-processor, so calling this with non-literals will 22 * likely not do what you want. 23 * 24 * For example: 25 * 26 * @code{c} 27 * #define MY_OBJ_ID 3 28 * LWM2M_PATH(MY_OBJ_ID, 0, 1) 29 * @endcode 30 * 31 * would evaluate to "3/0/1", while 32 * 33 * @code{c} 34 * int x = 3; 35 * LWM2M_PATH(x, 0, 1) 36 * @endcode 37 * 38 * evaluates to "x/0/1". 39 */ 40 #define LWM2M_PATH(...) \ 41 LWM2M_PATH_MACRO(__VA_ARGS__, LWM2M_PATH4, LWM2M_PATH3, \ 42 LWM2M_PATH2, LWM2M_PATH1)(__VA_ARGS__) 43 44 45 /** @cond INTERNAL_HIDDEN */ 46 /* Internal helper macros for the LWM2M_PATH macro */ 47 #define LWM2M_PATH_VA_NUM_ARGS(...) \ 48 LWM2M_PATH_VA_NUM_ARGS_IMPL(__VA_ARGS__, 5, 4, 3, 2, 1) 49 #define LWM2M_PATH_VA_NUM_ARGS_IMPL(_1, _2, _3, _4, N, ...) N 50 51 #define LWM2M_PATH1(_x) #_x 52 #define LWM2M_PATH2(_x, _y) #_x "/" #_y 53 #define LWM2M_PATH3(_x, _y, _z) #_x "/" #_y "/" #_z 54 #define LWM2M_PATH4(_a, _x, _y, _z) #_a "/" #_x "/" #_y "/" #_z 55 56 #define LWM2M_PATH_MACRO(_1, _2, _3, _4, NAME, ...) NAME 57 /** @endcond */ 58 59 /** 60 * @brief Initialize LwM2M object structure 61 * 62 * Accepts at least one and up to four arguments. Fill up @ref lwm2m_obj_path structure 63 * and sets the level. 64 * 65 * For example: 66 * 67 * @code{c} 68 * struct lwm2m_obj_path p = LWM2M_OBJ(MY_OBJ, 0, RESOURCE); 69 * @endcode 70 * 71 * Can also be used in place of function argument to return the structure allocated from stack 72 * 73 * @code{c} 74 * lwm2m_notify_observer_path(&LWM2M_OBJ(MY_OBJ, inst_id, RESOURCE)); 75 * @endcode 76 * 77 */ 78 #define LWM2M_OBJ(...) \ 79 GET_OBJ_MACRO(__VA_ARGS__, LWM2M_OBJ4, LWM2M_OBJ3, LWM2M_OBJ2, LWM2M_OBJ1)(__VA_ARGS__) 80 81 /** @cond INTERNAL_HIDDEN */ 82 /* Internal helper macros for the LWM2M_OBJ macro */ 83 #define GET_OBJ_MACRO(_1, _2, _3, _4, NAME, ...) NAME 84 #define LWM2M_OBJ1(oi) (struct lwm2m_obj_path) {.obj_id = oi, .level = 1} 85 #define LWM2M_OBJ2(oi, oii) (struct lwm2m_obj_path) {.obj_id = oi, .obj_inst_id = oii, .level = 2} 86 #define LWM2M_OBJ3(oi, oii, ri) (struct lwm2m_obj_path) \ 87 {.obj_id = oi, .obj_inst_id = oii, .res_id = ri, .level = 3} 88 #define LWM2M_OBJ4(oi, oii, ri, rii) (struct lwm2m_obj_path) \ 89 {.obj_id = oi, .obj_inst_id = oii, .res_id = ri, .res_inst_id = rii, .level = 4} 90 /** @endcond */ 91 92 /** @} */ 93 94 #endif /* ZEPHYR_INCLUDE_NET_LWM2M_PATH_H_ */ 95
