[Bug 38392] New: Divide by zero in dlls/user32/Edit.c source file

https://bugs.winehq.org/show_bug.cgi?id=38392

Bug ID: 38392
           Summary: Divide by zero in dlls/user32/Edit.c  source file
           Product: Wine
           Version: unspecified
          Hardware: x86
                OS: Linux
            Status: UNCONFIRMED
          Severity: normal
          Priority: P2
         Component: user32
          Assignee: [e-mail]
          Reporter: [e-mail]
      Distribution: ---

Upon calculation of line count in get_vertical_line_count function, line_height
field might take value of 0, which results in division by zero error. E.g. I
encountered this when dynamically creating hidden text control in Clarion
language, which uses WinAPI call for that.

Here's my hotfix for this bug (return 1 if es->line_height <= 0):

{{{
static inline INT get_vertical_line_count(EDITSTATE *es) {
  if (es->line_height <=0) {
    return 1;
  }
  else {
    INT vlc = (es->format_rect.bottom - es->format_rect.top) / es->line_height;
    return max(1,vlc);
  }
}
}}}

The problem shows up in WINE versions 1.4.1 - 1.7.40. (at least on CentOS 6,
CentOS 7, Debian 7 and Mint 17).

Please, fix this bug in official release.