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