A complete C++ download manager source code
This is the source code for a C++ download manager that you can edit. I searched for it for a long-time because i needed to write my own but couldn’t write because of time limitations.
The code if displayed below
#include <windows.h>
#include <stdio.h>
#include <wininet.h>
#define FILE_BUFFER_SIZE 4096
#define RETRY_READ 10
char sInputUrl [INTERNET_MAX_URL_LENGTH] = “”;
char sOutputPath [MAX_PATH] = “”;
HANDLE hStdOut;
DWORD dReadFileCount, dWriteFileCount, dWriteFileTotal;
VOID Banner ()
{
printf (“\nWDJ EasyDL V1.00 / 07-21-96 Sven B. Schreiber\n\n”);
}
VOID Usage ()
{
printf (“Usage: EasyDL <Source URL> [<Destination>]\n”);
printf (“\n”);
printf (“Valid URL schemes are ftp, http, and gopher.\n”);
printf (“If no destination is specified, STDOUT is assumed.\n”);
}
DWORD BytesPerSecond (SYSTEMTIME *pStartTime,
DWORD dBytes)
{
SYSTEMTIME CurrentTime;
DWORD dStartSecond, dSeconds;
dStartSecond = (((DWORD) pStartTime->wSecond) ) +
(((DWORD) pStartTime->wMinute) * 60 ) +
(((DWORD) pStartTime->wHour ) * 60 * 60);
GetSystemTime (&CurrentTime);
dSeconds = (((DWORD) CurrentTime.wSecond) ) +
(((DWORD) CurrentTime.wMinute) * 60 ) +
(((DWORD) CurrentTime.wHour ) * 60 * 60) -
dStartSecond;
if (dSeconds & 0×80000000) {dSeconds += 24 * 60 * 60;}
return (dSeconds ? (dBytes / dSeconds) : 0);
}
// =================================================================
// INTERNET INTERFACE
// =================================================================
VOID DownloadFile (HINTERNET hSource,
HANDLE hDestination)
{
UINT uRetry;
BOOL fOk;
BYTE bFileBuffer [FILE_BUFFER_SIZE];
SYSTEMTIME StartTime;
if (hDestination == hStdOut)
printf (“\n————— [ BEGIN ] —————\n”);
dWriteFileTotal = 0;
GetSystemTime (&StartTime);
do
{
if (hDestination != hStdOut)
{
printf (“\r%lu bytes transferred … “,
dWriteFileTotal);
printf (“(%lu bytes/sec) “,
BytesPerSecond (&StartTime, dWriteFileTotal));
}
uRetry = 0;
do
{
dReadFileCount = 0;
fOk = InternetReadFile (hSource,
bFileBuffer,
FILE_BUFFER_SIZE,
&dReadFileCount);
}
while (!(dReadFileCount || fOk || uRetry++ == RETRY_READ));
if (dReadFileCount)
{
dWriteFileCount = 0;
fOk = WriteFile (hDestination,
bFileBuffer,
dReadFileCount,
&dWriteFileCount,
NULL);
if (fOk = fOk && (dReadFileCount == dWriteFileCount))
dWriteFileTotal += dWriteFileCount;
else
{
dReadFileCount = 0;
printf (“\n!!! Error writing data !!!”);
}
}
else
{
if (!fOk)
printf (“\n!!! Error reading data !!!”);
}
}
while (dReadFileCount);
if (hDestination == hStdOut)
printf (“\n—————- [ END ] —————-”);
printf (“\n\n”);
}
// —————————————————————–
VOID GetInternetFile (HINTERNET hSession,
char sSource [],
char sDestination [])
{
HINTERNET hSource;
HANDLE hDestination;
printf (“Opening \”%s\”\n”, sSource);
hSource = InternetOpenUrl (hSession,
sSource,
NULL,
0xFFFFFFFF,
INTERNET_FLAG_DONT_CACHE |
INTERNET_FLAG_RAW_DATA,
0);
if (hSource != NULL)
{
if (!sOutputPath [0])
{
printf (“Output directed to STDOUT\n”);
hDestination = hStdOut;
}
else
{
printf (“Creating \”%s\”\n”, sDestination);
hDestination = CreateFile (sDestination,
GENERIC_WRITE,
FILE_SHARE_READ,
NULL,
CREATE_NEW,
FILE_FLAG_WRITE_THROUGH |
FILE_FLAG_SEQUENTIAL_SCAN,
NULL);
}
if (hDestination != INVALID_HANDLE_VALUE)
{
printf (“\nStarting Download\n”);
DownloadFile (hSource, hDestination);
if (hDestination != hStdOut)
{
printf (“Closing \”%s\”\n”, sDestination);
CloseHandle (hDestination);
}
}
else
printf (“\n!!! Output file not created !!!\n\n”);
printf (“Closing \”%s\”\n”, sSource);
InternetCloseHandle (hSource);
}
else
printf (“\n!!! Internet URL not opened !!!\n\n”);
}
// —————————————————————–
VOID InternetSession (char sCaller [])
{
HINTERNET hSession;
printf (“Opening Internet Session \”%s\”\n”, sCaller);
hSession = InternetOpen (sCaller,
LOCAL_INTERNET_ACCESS,
NULL,
INTERNET_INVALID_PORT_NUMBER,
INTERNET_FLAG_DONT_CACHE);
if (hSession != NULL)
{
GetInternetFile (hSession, sInputUrl, sOutputPath);
printf (“Closing Internet Session \”%s\”\n”, sCaller);
InternetCloseHandle (hSession);
}
else
printf (“\n!!! Internet session not opened !!!\n”);
}
// =================================================================
// MAIN PROGRAM
// =================================================================
void main (int argc, char *argv [], char *envp [])
{
hStdOut = GetStdHandle (STD_OUTPUT_HANDLE);
Banner ();
if (argc > 1)
{lstrcpyn (sInputUrl, argv [1], INTERNET_MAX_URL_LENGTH);}
if (argc > 2)
{lstrcpyn (sOutputPath, argv [2], MAX_PATH);}
if (sInputUrl [0])
InternetSession (“EasyDL/1.00″);
else
Usage ();
}
