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
load_json()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