1 /** 2 * Copyright © 2018 IBM Corporation 3 * 4 * Licensed under the Apache License, Version 2.0 (the "License"); 5 * you may not use this file except in compliance with the License. 6 * You may obtain a copy of the License at 7 * 8 * http://www.apache.org/licenses/LICENSE-2.0 9 * 10 * Unless required by applicable law or agreed to in writing, software 11 * distributed under the License is distributed on an "AS IS" BASIS, 12 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. 13 * See the License for the specific language governing permissions and 14 * limitations under the License. 15 */ 16 #include <stdio.h> 17 #include <stdlib.h> 18 #include "gpio_json.h" 19 20 #define GPIO_FILE "/etc/default/obmc/gpio/gpio_defs.json" 21 22 cJSON* load_json() 23 { 24 FILE* fd = fopen(GPIO_FILE, "r"); 25 if (!fd) 26 { 27 fprintf(stderr, "Unable to open GPIO JSON file %s\n", GPIO_FILE); 28 return NULL; 29 } 30 31 fseek(fd, 0, SEEK_END); 32 long size = ftell(fd); 33 rewind(fd); 34 35 char* data = malloc(size + 1); 36 37 size_t rc = fread(data, 1, size, fd); 38 fclose(fd); 39 if (rc != size) 40 { 41 free(data); 42 fprintf(stderr, "Only read %d out of %ld bytes of GPIO file %s\n", 43 rc, size, GPIO_FILE); 44 return NULL; 45 } 46 47 data[size] = '\0'; 48 cJSON* json = cJSON_Parse(data); 49 free(data); 50 51 if (json == NULL) 52 { 53 fprintf(stderr, "Failed parsing GPIO file %s\n", GPIO_FILE); 54 55 const char* error_loc = cJSON_GetErrorPtr(); 56 if (error_loc != NULL) 57 { 58 fprintf(stderr, "JSON error at %s\n", error_loc); 59 } 60 } 61 return json; 62 } 63