1 /* 2 * Copyright (C) 2024 BlueKitchen GmbH 3 * 4 * Redistribution and use in source and binary forms, with or without 5 * modification, are permitted provided that the following conditions 6 * are met: 7 * 8 * 1. Redistributions of source code must retain the above copyright 9 * notice, this list of conditions and the following disclaimer. 10 * 2. Redistributions in binary form must reproduce the above copyright 11 * notice, this list of conditions and the following disclaimer in the 12 * documentation and/or other materials provided with the distribution. 13 * 3. Neither the name of the copyright holders nor the names of 14 * contributors may be used to endorse or promote products derived 15 * from this software without specific prior written permission. 16 * 4. Any redistribution, use, or modification is done solely for 17 * personal benefit and not for any commercial purpose or for 18 * monetary gain. 19 * 20 * THIS SOFTWARE IS PROVIDED BY BLUEKITCHEN GMBH AND CONTRIBUTORS 21 * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT 22 * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS 23 * FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL BLUEKITCHEN 24 * GMBH OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, 25 * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, 26 * BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS 27 * OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED 28 * AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, 29 * OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF 30 * THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 31 * SUCH DAMAGE. 32 * 33 * Please inquire about commercial licensing options at 34 * [email protected] 35 * 36 */ 37 38 #define BTSTACK_FILE__ "btstack_tlv_builder.c" 39 40 #include "btstack_tlv_builder.h" 41 42 #include "btstack_bool.h" 43 #include "btstack_config.h" 44 #include "btstack_debug.h" 45 #include "btstack_util.h" 46 47 #include <stdint.h> 48 #include <string.h> 49 50 static void btstack_tlv_builder_increase_tag(btstack_tlv_builder_context_t * context, uint16_t size){ 51 btstack_assert((context->write_pos + size) < context->size); 52 context->write_pos += size; 53 btstack_assert((((uint16_t)context->buffer[context->len_pos]) + size) <= 255); 54 context->buffer[context->len_pos] += size; 55 } 56 57 void btstack_tlv_builder_init(btstack_tlv_builder_context_t * context, uint8_t * buffer, uint16_t size){ 58 btstack_assert(buffer != NULL); 59 context->buffer = buffer; 60 context->size = size; 61 context->write_pos = 0; 62 } 63 64 uint16_t btstack_tlv_builder_remaining_space(btstack_tlv_builder_context_t * context){ 65 return context->size - context->write_pos; 66 } 67 68 uint16_t btstack_tlv_builder_get_length(btstack_tlv_builder_context_t * context){ 69 return context->write_pos; 70 } 71 72 void btstack_tlv_builder_add_tag(btstack_tlv_builder_context_t * context, uint8_t tag){ 73 // update write pos 74 btstack_assert((context->write_pos + 2) < context->size); 75 // track len pos 76 context->buffer[context->write_pos++] = tag; 77 // add empty tag 78 context->len_pos = context->write_pos; 79 context->buffer[context->write_pos++] = 0; 80 } 81 82 void btstack_tlv_builder_add_08(btstack_tlv_builder_context_t * context, uint8_t value){ 83 btstack_assert(context->write_pos != 0); 84 uint16_t write_pos = context->write_pos; 85 btstack_tlv_builder_increase_tag(context, 1); 86 context->buffer[write_pos] = value; 87 } 88 89 void btstack_tlv_builder_add_big_endian_16(btstack_tlv_builder_context_t * context, uint16_t value) { 90 btstack_assert(context->write_pos != 0); 91 uint16_t write_pos = context->write_pos; 92 btstack_tlv_builder_increase_tag(context, 2); 93 big_endian_store_16(context->buffer, write_pos, value); 94 } 95 96 void btstack_tlv_builder_add_big_endian_24(btstack_tlv_builder_context_t * context, uint32_t value) { 97 btstack_assert(context->write_pos != 0); 98 uint16_t write_pos = context->write_pos; 99 btstack_tlv_builder_increase_tag(context, 3); 100 big_endian_store_24(context->buffer, write_pos, value); 101 } 102 103 void btstack_tlv_builder_add_big_endian_32(btstack_tlv_builder_context_t * context, uint32_t value) { 104 btstack_assert(context->write_pos != 0); 105 uint16_t write_pos = context->write_pos; 106 btstack_tlv_builder_increase_tag(context, 4); 107 big_endian_store_32(context->buffer, write_pos, value); 108 } 109 110 void btstack_tlv_builder_add_bytes(btstack_tlv_builder_context_t * context, const uint8_t * data, uint16_t length) { 111 btstack_assert(context->write_pos != 0); 112 btstack_assert(data != NULL); 113 btstack_tlv_builder_increase_tag(context, length); 114 memcpy(&context->buffer[context->write_pos], data, length); 115 context->write_pos += length; 116 } 117 118 void btstack_tlv_builder_add_string(btstack_tlv_builder_context_t * context, const char * text) { 119 uint16_t length = (uint16_t)strlen(text); 120 btstack_tlv_builder_add_bytes(context, (const uint8_t *) text, length); 121 } 122