Progress Bars

#include <stdlib.h>
#include <stdio.h>
#include <unistd.h>
#include <time.h>
#include <curl/curl.h>
typedef void (*progressCallback)(unsigned, unsigned);
void waitLoop(unsigned ms, unsigned interval, progressCallback callback)
{
        unsigned i, j, s, count = ms/interval;
        for (i = 0, s = 0; i < ms; i += interval, ++s)
        {
                (*callback)(s % 4, (i * 100) / ms);
                usleep(interval * 1000);
        }
        (*callback)(0, 100);
        printf("\n");
}
struct cURLProgress
{
        double lastrun;
        CURL *curl;
        progressCallback callback;
        unsigned interval;
        unsigned char step;
};
static int downloadProgress(void *p, curl_off_t dltotal, curl_off_t dlnow, curl_off_t ultotal, curl_off_t ulnow)
{
        struct cURLProgress *info;
        CURL *curl;
        double curtime;
        info = p;
        curl = info->curl;
        curtime = 0;
        curl_easy_getinfo(curl, CURLINFO_TOTAL_TIME, &curtime);
        if ((curtime - info->lastrun) > ((double)info->interval / 1000.0) && dltotal > 0)
        {
                info->lastrun = curtime;
                (*info->callback)(info->step++ % 4, (dlnow * 100) / dltotal);
        }
        return 0;
}
size_t cURLWriteData(void *ptr, size_t size, size_t nmemb, FILE *stream)
{ return fwrite(ptr, size, nmemb, stream); }
int downloadFile(const char *URL, const char *path, unsigned interval, progressCallback callback)
{
        CURL *curl;
        CURLcode res;
        FILE *fp;
        struct cURLProgress progressInfo;
        res = CURLE_OK;
        if ((curl = curl_easy_init()) != NULL)
        {
                progressInfo.lastrun = 0;
                progressInfo.curl = curl;
                progressInfo.callback = callback;
                progressInfo.interval = interval;
                progressInfo.step = 0;
                fp = fopen(path, "wb");
                curl_easy_setopt(curl, CURLOPT_URL, URL);
                curl_easy_setopt(curl, CURLOPT_XFERINFOFUNCTION, downloadProgress);
                curl_easy_setopt(curl, CURLOPT_XFERINFODATA, &progressInfo);
                curl_easy_setopt(curl, CURLOPT_NOPROGRESS, 0L);
                curl_easy_setopt(curl, CURLOPT_WRITEFUNCTION, cURLWriteData);
                curl_easy_setopt(curl, CURLOPT_WRITEDATA, fp);
                if ((res = curl_easy_perform(curl)) == CURLE_OK)
                    (*callback)(0, 100);
                curl_easy_cleanup(curl);
                fclose(fp);
        }
        printf("\n");
        return res;
}
void progress(unsigned spin, unsigned step)
{
        int i;
        const char *pgstep = "|\\-/";
        printf("\r"); for (i = 0; i < 109; ++i); printf(" "); printf("\r ["); // clear
        for (i = 0; i < step; ++i) printf("#"); // print bar
        for (; i < 100; ++i) printf(" "); // print blank space
        printf("] %c\b", step > 99 ? ' ' : pgstep[spin]);
        fflush(stdout);
}
int main()
{
        int retVal;
        srand(time(NULL));
        waitLoop((rand() % 15 + 1) * 1000, 75, &progress);
        retVal = downloadFile(
                   "http://mirror.digitalnova.at/archlinux/iso/2018.03.01/archlinux-2018.03.01-x86_64.iso",
                   "archlinux.iso", 300, &progress);
        if (retVal != 0) fprintf(stderr, "There was an error downloading your file\n");
        return 0;
}