Re: [PATCH v4 06/10] shell32/autocomplete: Dynamically allocate hwndText so it can handle arbitrary sizes

[Huw Davies]

On Mon, Sep 10, 2018 at 10:09:36PM +0300, Gabriel Ivăncescu wrote:
> Signed-off-by: Gabriel Ivăncescu
>
> dlls/shell32/autocomplete.c | 31 ++++++++++++++++++-------------
>  1 file changed, 18 insertions(+), 13 deletions(-)
>
> diff --git a/dlls/shell32/autocomplete.c b/dlls/shell32/autocomplete.c
> index 6f97665..7421679 100644
> --- a/dlls/shell32/autocomplete.c
> +++ b/dlls/shell32/autocomplete.c
> @@ -134,10 +134,11 @@ static LRESULT APIENTRY ACEditSubclassProc(HWND hwnd, UINT uMsg, WPARAM wParam,
>  {
>      IAutoCompleteImpl *This = GetPropW(hwnd, autocomplete_propertyW);
>      HRESULT hr;
> - WCHAR hwndText[255];
> - WCHAR *hwndText;
> - UINT len, size, cpt;
> RECT r;
> BOOL displayall = FALSE;
> - int cpt, height, sel;
> -
>
> int height, sel;
>
> if (!This->enabled) return CallWindowProcW(This->wpOrigEditProc, hwnd, uMsg, wParam, lParam);
>
> @@ -154,10 +155,11 @@ static LRESULT APIENTRY ACEditSubclassProc(HWND hwnd, UINT uMsg, WPARAM wParam,
>              }
>              return CallWindowProcW(This->wpOrigEditProc, hwnd, uMsg, wParam, lParam);
>          case WM_KEYUP:
> -
>    {
> -
>        int len;
> -
> -
>        GetWindowTextW(hwnd, hwndText, ARRAY_SIZE(hwndText));
> -
>        len = SendMessageW(hwnd, WM_GETTEXTLENGTH, 0, 0);
> -
>        size = len + 1;
> -
>        if (!(hwndText = heap_alloc(size * sizeof(WCHAR))))
> -
>            return 0;
> -
>        len = SendMessageW(hwnd, WM_GETTEXT, size, (LPARAM)hwndText);
>
>        switch(wParam) {
>            case VK_RETURN:
>
> @@ -165,7 +167,6 @@ static LRESULT APIENTRY ACEditSubclassProc(HWND hwnd, UINT uMsg, WPARAM wParam,
>                      if (This->quickComplete && (GetKeyState(VK_CONTROL) & 0x8000))
>                      {
>                          WCHAR *buf;
> -
>                    size_t len = strlenW(hwndText);
>                    size_t sz = strlenW(This->quickComplete) + 1 + len;
>                    if ((buf = heap_alloc(sz * sizeof(WCHAR))))
>                    {
>
> @@ -178,9 +179,11 @@ static LRESULT APIENTRY ACEditSubclassProc(HWND hwnd, UINT uMsg, WPARAM wParam,
>                  if (This->options & ACO_AUTOSUGGEST)
>                      ShowWindow(This->hwndListBox, SW_HIDE);
> -
>                heap_free(hwndText);
>                return 0;
>            case VK_LEFT:
>            case VK_RIGHT:
> -
>                heap_free(hwndText);
>                return 0;
>            case VK_UP:
>            case VK_DOWN:
>
> @@ -196,6 +199,7 @@ static LRESULT APIENTRY ACEditSubclassProc(HWND hwnd, UINT uMsg, WPARAM wParam,
>                           /* We must display all the entries */
>                           displayall = TRUE;
>                      } else {
> -
>                    heap_free(hwndText);
>                    if (IsWindowVisible(This->hwndListBox)) {
>                        int count;
>
> @@ -231,21 +235,23 @@ static LRESULT APIENTRY ACEditSubclassProc(HWND hwnd, UINT uMsg, WPARAM wParam,
>                  case VK_BACK:
>                  case VK_DELETE:
>                      if ((! *hwndText) && (This->options & ACO_AUTOSUGGEST)) {
> -
>                    heap_free(hwndText);
>                    ShowWindow(This->hwndListBox, SW_HIDE);
>                    return CallWindowProcW(This->wpOrigEditProc, hwnd, uMsg, wParam, lParam);
>                }
>                break;
>        }
>
> -
>        if (len + 1 != size)
> -
>            hwndText = heap_realloc(hwndText, len + 1);

(len + 1) * sizeof(WCHAR)

This is a good example of why we want small patches.  It would have
been much harder to spot that in one of your earlier versions.

Huw.