how to send a bitmap to server? using C - c

Question

I'm trying to send a bitmap image to server but server can't receive a bitmap file.
I've checked sending byte in client and receiving byte in server.
Before this Question, I asked similar problem in stack overflow.
And I know I don't check sending byte and receiving byte.
so I check those, but server can't receive a bitmap. server just print gray.
send function returns 3244104 and receive function returns 3244104
Those are same. help me.........
here is my server code.
LRESULT CALLBACK WndProc(HWND hwnd, UINT iMsg,
WPARAM wParam, LPARAM lParam)
{
HDC hdcWindow;
HDC hdcbuffer;
HBITMAP hbm = NULL;
static BITMAPINFOHEADER bi;
static WSADATA wsadata;
static SOCKET s, cs;
static SOCKADDR_IN addr = { 0 }, c_addr;
int size;
static char* buffer;
switch (iMsg)
{
case WM_CREATE:
WSAStartup(MAKEWORD(2, 2), &wsadata);
s = socket(AF_INET, SOCK_STREAM, 0);
addr.sin_family = AF_INET;
addr.sin_port = 20;
addr.sin_addr.s_addr = htonl(INADDR_ANY);
bind(s, (LPSOCKADDR)&addr, sizeof(addr));
WSAAsyncSelect(s, hwnd, WM_ASYNC, FD_ACCEPT);
if (listen(s, 5) == -1)
return 0;
break;
case WM_ASYNC:
switch (lParam)
{
case FD_ACCEPT:
size = sizeof(c_addr);
cs = accept(s, (LPSOCKADDR)&c_addr, &size);
WSAAsyncSelect(cs, hwnd, WM_ASYNC, FD_READ);
break;
case FD_READ:
hdcWindow = GetDC(hwnd);
hdcbuffer = CreateCompatibleDC(hdcWindow);
recv(cs, (char*)&bi, sizeof(bi), 0);
buffer = (char*)malloc(bi.biSizeImage);
int i = recv(cs, buffer, bi.biSizeImage, 0);
hbm = CreateCompatibleBitmap(hdcWindow, bi.biWidth, bi.biHeight);
SelectObject(hdcbuffer, hbm);
SetDIBits(hdcbuffer, hbm, 0, bi.biHeight, buffer, (BITMAPINFO*)&bi, DIB_RGB_COLORS);
BitBlt(hdcWindow,
0, 0,
bi.biWidth, bi.biHeight,
hdcbuffer,
0, 0,
SRCCOPY);
free(buffer);
DeleteObject(hbm);
ReleaseDC(hwnd, hdcWindow);
DeleteDC(hdcbuffer);
break;
}
break;
case WM_DESTROY:
closesocket(cs);
closesocket(s);
WSACleanup();
PostQuitMessage(0);
break;
}
return DefWindowProc(hwnd, iMsg, wParam, lParam);
}
this is my client code.
HINSTANCE hinst;
char* lpbitmap = NULL;
SOCKET s;
RECT rcClient;
HDC hdcScreen;
HDC hdcWindow;
int CaptureAnImage(HWND hWnd)
{
static HDC hdcMemDC;
static HBITMAP hbmScreen;
static BITMAP bmpScreen;
hdcScreen = GetDC(NULL);
hdcWindow = GetDC(hWnd);
hdcMemDC = CreateCompatibleDC(hdcWindow);
GetClientRect(hWnd, &rcClient);
SetStretchBltMode(hdcWindow, HALFTONE);
StretchBlt(hdcWindow,
0, 0,
rcClient.right, rcClient.bottom,
hdcScreen,
0, 0,
GetSystemMetrics(SM_CXSCREEN),
GetSystemMetrics(SM_CYSCREEN),
SRCCOPY);
hbmScreen = CreateCompatibleBitmap(hdcWindow, rcClient.right - rcClient.left, rcClient.bottom
- rcClient.top);
SelectObject(hdcMemDC, hbmScreen);
BitBlt(hdcMemDC,
0, 0,
rcClient.right - rcClient.left, rcClient.bottom - rcClient.top,
hdcWindow,
0, 0,
SRCCOPY);
GetObject(hbmScreen, sizeof(BITMAP), &bmpScreen);
BITMAPINFOHEADER bi;
bi.biSize = sizeof(BITMAPINFOHEADER);
bi.biWidth = bmpScreen.bmWidth;
bi.biHeight = bmpScreen.bmHeight;
bi.biPlanes = 1;
bi.biBitCount = 32;
bi.biCompression = BI_RGB;
bi.biSizeImage = 0;
bi.biXPelsPerMeter = 0;
bi.biYPelsPerMeter = 0;
bi.biClrUsed = 0;
bi.biClrImportant = 0;
GetDIBits(hdcWindow, hbmScreen, 0, bmpScreen.bmHeight, NULL, (BITMAPINFO*)&bi,
DIB_RGB_COLORS);
if (!bi.biSizeImage)
{
bi.biSizeImage = (((bi.biWidth*bi.biBitCount + 0x1F)&~0x1F) >> 3)*bi.biHeight;
}
lpbitmap = (char*)malloc(bi.biSizeImage);
GetDIBits(hdcWindow, hbmScreen, 0,
(UINT)bmpScreen.bmHeight,
lpbitmap,
(BITMAPINFO*)&bi, DIB_RGB_COLORS);
send(s, (char*)&bi, sizeof(bi), 0);
send(s, lpbitmap, bi.biSizeImage, 0);
free(lpbitmap);
DeleteObject(hbmScreen);
DeleteObject(hdcMemDC);
ReleaseDC(NULL, hdcScreen);
ReleaseDC(hWnd, hdcWindow);
return 0;
}
help me......
I can't solve this problem......