使用C对URL进行标记化

#include <stdio.h>
#include <stdlib.h>
#include <string.h>

// URL标记化函数
char* url_encode(const char* url) {
    int len = strlen(url);
    char* encoded_url = (char*)malloc(3 * len + 1); // 保证足够的空间存放编码后的URL

    int j = 0;
    for (int i = 0; i < len; i++) {
        if ((url[i] >= 'A' && url[i] <= 'Z') ||
            (url[i] >= 'a' && url[i] <= 'z') ||
            (url[i] >= '0' && url[i] <= '9') ||
            url[i] == '-' || url[i] == '_' || url[i] == '.' || url[i] == '~') {
            encoded_url[j++] = url[i];
        } else {
            sprintf(encoded_url + j, "%%%02X", (unsigned char)url[i]);
            j += 3;
        }
    }
    encoded_url[j] = '\0';

    return encoded_url;
}

int main() {
    const char* url = "https://www.example.com/path/file name.html";
    char* encoded_url = url_encode(url);
    printf("Encoded URL: %s\n", encoded_url);
    free(encoded_url);

    return 0;
}