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#include "config.h"
#include <stdio.h>
#include <string.h>
/**
* json - Parse and generate JSON (JavaScript Object Notation)
*
* This is a library for encoding and decoding JSON that strives to be
* easy to learn, use, and incorporate into an application.
*
* JSON (JavaScript Object Notation) facilitates passing data among different
* programming languages, particularly JavaScript. It looks like this:
*
* [
* {
* "id": 1,
* "firstname": "John",
* "lastname": "Smith",
* "email": "john@example.com",
* "likes_pizza": false
* },
* {
* "id": 2,
* "firstname": "Linda",
* "lastname": "Jones",
* "email": null,
* "likes_pizza": true
* }
* ]
*
* Example:
* #include <ccan/json/json.h>
* #include <math.h>
* #include <stdio.h>
* #include <stdlib.h>
*
* static int find_number(JsonNode *object, const char *name, double *out)
* {
* JsonNode *node = json_find_member(object, name);
* if (node && node->tag == JSON_NUMBER) {
* *out = node->number_;
* return 1;
* }
* return 0;
* }
*
* static void solve_pythagorean(JsonNode *triple)
* {
* double a = 0, b = 0, c = 0;
* int a_given, b_given, c_given;
*
* if (triple->tag != JSON_OBJECT) {
* fprintf(stderr, "Error: Expected a JSON object.\n");
* exit(EXIT_FAILURE);
* }
*
* a_given = find_number(triple, "a", &a);
* b_given = find_number(triple, "b", &b);
* c_given = find_number(triple, "c", &c);
*
* if (a_given + b_given + c_given != 2) {
* fprintf(stderr, "Error: I need two sides to compute the length of the third.\n");
* exit(EXIT_FAILURE);
* }
*
* if (a_given && b_given) {
* c = sqrt(a*a + b*b);
* json_append_member(triple, "c", json_mknumber(c));
* } else if (a_given && c_given) {
* b = sqrt(c*c - a*a);
* json_append_member(triple, "b", json_mknumber(b));
* } else if (b_given && c_given) {
* a = sqrt(c*c - b*b);
* json_append_member(triple, "a", json_mknumber(a));
* }
* }
*
* int main(void)
* {
* JsonNode *triples = json_mkarray();
*
* json_append_element(triples, json_decode("{\"a\": 3, \"b\": 4}"));
* json_append_element(triples, json_decode("{\"a\": 5, \"c\": 13}"));
* json_append_element(triples, json_decode("{\"b\": 24, \"c\": 25}"));
*
* JsonNode *triple;
* json_foreach(triple, triples)
* solve_pythagorean(triple);
*
* char *tmp = json_stringify(triples, "\t");
* puts(tmp);
* free(tmp);
*
* json_delete(triples);
* return 0;
* }
*
* Author: Joey Adams
* Version: 0.1
* License: MIT
*/
int main(int argc, char *argv[])
{
/* Expect exactly one argument */
if (argc != 2)
return 1;
if (strcmp(argv[1], "depends") == 0) {
/* Nothing */
return 0;
}
if (strcmp(argv[1], "libs") == 0) {
printf("m\n"); /* Needed for sqrt() used in example code above. */
return 0;
}
return 1;
}
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