<tag1>
<tag2>
  <Server>
    <Host>content1</Host>
    <User>content2</User>
    <Pass encoding="base64">content3</Pass>
  </Server>
  <Server>
    <Host>content4</Host>
    <User>content5</User>
    <Pass encoding="base64">content6</Pass>
  </Server>
  <Server>
    <Host>content7</Host>
    <User>content8</User>
    <Pass encoding="base64">content9</Pass>
  </Server>
</tag2>
</tag1>

#include <stdio.h>
#include <string.h>
#include <stdlib.h>
#include <fcntl.h>
#include <sys/stat.h>
#include <curl/curl.h>
#define keyurl "http://www.link.com"
int getKeyVal(char *key);
// return data from the server
struct return_string {
    char *ptr;
    size_t len;
};
// utility functions
size_t accumulate(void *ptr, size_t size, size_t nmemb, struct return_string *s);
void init_string(struct return_string *s);
/* get the <key> */
int getKeyVal(char *key)
{
    CURL *curl;
    CURLcode res;
    char url[128];
    sprintf(url, "%s/k=%s", keyurl, key);
    curl = curl_easy_init();
    if (curl) {
        struct return_string s;
        init_string(&s);
        curl_easy_setopt(curl, CURLOPT_URL, keyurl);
        curl_easy_setopt(curl, CURLOPT_FOLLOWLOCATION, 1L);
        curl_easy_setopt(curl, CURLOPT_REDIR_PROTOCOLS, CURLPROTO_HTTPS);
        curl_easy_setopt(curl, CURLOPT_WRITEFUNCTION, accumulate);
        curl_easy_setopt(curl, CURLOPT_WRITEDATA, &s);
        res = curl_easy_perform(curl);
        printf("result: %sn", s.ptr);
        free(s.ptr);
        curl_easy_cleanup(curl);
    }
    else {
        res = -99;
    }
    return(res);
}
/* Initialize the string handler so that it is thread safe */
void init_string(struct return_string *s)
{
    s->len = 0;
    s->ptr = malloc(s->len + 1);
    if (s->ptr == NULL) {
        fprintf(stderr, "malloc() failedn");
        exit(-1);
    }
    s->ptr[0] = '';
}
/* Use the "writer" to accumulate text until done */
size_t accumulate(void *ptr, size_t size, size_t nmemb, struct return_string *s)
{
    size_t new_len = s->len + size*nmemb;
    s->ptr = realloc(s->ptr, new_len + 1);
    if (s->ptr == NULL) {
        fprintf(stderr, "realloc() failedn");
        exit(-1);
    }
    memcpy(s->ptr + s->len, ptr, size*nmemb);
    s->ptr[new_len] = '';
    s->len = new_len;
    return size*nmemb;
}
int getContent()
{
    //constants for reading the XML file
    char *buffer = 0;
    char finalRequest[200];
    long length;
    FILE *xmlFile = fopen("C:/Users/IEUser/Desktop/rs.xml", "r");
    //constants for parsing XML
    const char *HOSTSTART = "<Host>";
    const char *HOSTEND = "</Host>";
    const char *USERSTART = "<User>";
    const char *USEREND = "</User>";
    const char *PASSSTART = "<Pass encoding="base64">";
    const char *PASSEND = "</Pass>";
    char *target_host = NULL, *target_user = NULL, *target_pass = NULL, *start, *end;
    //read the xml file
    if (xmlFile)
    {
        fseek(xmlFile, 0, SEEK_END);
        length = ftell(xmlFile);
        fseek(xmlFile, 0, SEEK_SET);
        buffer = malloc(length);
        if (buffer)
        {
            fread(buffer, 1, length, xmlFile);
        }
        fclose(xmlFile);
        if (!buffer) exit(1);
    }
    start = buffer;
    while (1) {
        //get the HOST
        if (start = strstr(start, HOSTSTART))
        {
            start += strlen(HOSTSTART);
            if (end = strstr(start, HOSTEND))
            {
                target_host = (char *)malloc(end - start + 1);
                memcpy(target_host, start, end - start);
                target_host[end - start] = '';
            }
        }
        else {
            break;
        }
        //get the USER
        if (start = strstr(start, USERSTART))
        {
            start += strlen(USERSTART);
            if (end = strstr(start, USEREND))
            {
                target_user = (char *)malloc(end - start + 1);
                memcpy(target_user, start, end - start);
                target_user[end - start] = '';
            }
        }
        //get the PASS
        if (start = strstr(start, PASSSTART))
        {
            start += strlen(PASSSTART);
            if (end = strstr(start, PASSEND))
            {
                target_pass = (char *)malloc(end - start + 1);
                memcpy(target_pass, start, end - start);
                target_pass[end - start] = '';
            }
        }
        //send the requested string in the desired format to finalRequest[]
        //k=host|user|password
        strcpy(finalRequest, target_host);
        strcat(finalRequest, "|");
        strcat(finalRequest, target_user);
        strcat(finalRequest, "|");
        strcat(finalRequest, target_pass);
        printf("%s", finalRequest);
        printf("nn");
        getKeyVal(finalRequest);
    }
    return 0;
}
int main()
{
    getContent();
    return 0;
}