r/inplace_url.h

// Written by retoor@molodetz.nl

// This source code extracts URLs from an input string and replaces them inline with their respective content in Markdown style.

// Imports used: regex.h for regular expression operations, http.h and url.h for HTTP and URL-related utility functions. 

// MIT License


#include <regex.h>
#include "http.h"
#include "url.h"

void extract_urls(const char *input, char **urls, int *url_count) {
    const char *pattern = "https?://[^ ]+";
    regex_t regex;
    regcomp(&regex, pattern, REG_EXTENDED);
    regmatch_t match;
    const char *cursor = input;

    *url_count = 0;
    while (!regexec(&regex, cursor, 1, &match, 0)) {
        int length = match.rm_eo - match.rm_so;
        urls[*url_count] = strndup(cursor + match.rm_so, length);
        cursor += match.rm_eo;
        (*url_count)++;
    }

    regfree(&regex);
}

void inplace_urls_markdown_style(char *input, char **urls, char **contents, int url_count) {
    for (int i = 0; i < url_count; i++) {
        char *found = strstr(input, urls[i]);
        if (found) {
            char *new_text = (char *)malloc(strlen(input) + strlen(contents[i]) - strlen(urls[i]) + 1);
            strncpy(new_text, input, found - input);
            new_text[found - input] = '\0';
            strcat(new_text, contents[i]);
            strcat(new_text, found + strlen(urls[i]));

            free(input);
            input = new_text;
        }
    }
}