patch 9.0.1916: Crash when allocating large terminal screen

Problem:  Crash when allocating large terminal screen
Solution: Don't allow values > 1000 for terminal
          screen columns and rows

closes: #13126

Signed-off-by: Christian Brabandt <cb@256bit.org>

src/testdir/test_terminal2.vim

@@ -64,6 +64,14 @@ func Test_terminal_termwinsize_option_zero()
   call StopShellInTerminal(buf)
   exe buf . 'bwipe'
 
+  " This used to crash Vim
+  set termwinsize=10000*10000
+  let buf = Run_shell_in_terminal({})
+  let win = bufwinid(buf)
+  call assert_equal([1000, 1000], term_getsize(buf))
+  call StopShellInTerminal(buf)
+  exe buf . 'bwipe'
+
   set termwinsize=
 endfunc
 
@@ -271,6 +279,25 @@ func Test_terminal_resize()
   set statusline&
 endfunc
 
+func Test_terminal_resize2()
+  CheckNotMSWindows
+  set statusline=x
+  terminal
+  call assert_equal(2, winnr('$'))
+  let buf = bufnr()
+
+  " Wait for the shell to display a prompt
+  call WaitForAssert({-> assert_notequal('', term_getline(buf, 1))})
+
+  " This used to crash Vim
+  call feedkeys("printf '\033[8;99999;99999t'\<CR>", 'xt')
+  redraw
+
+  call feedkeys("exit\<CR>", 'xt')
+  call TermWait(buf)
+  set statusline&
+endfunc
+
 " must be nearly the last, we can't go back from GUI to terminal
 func Test_zz1_terminal_in_gui()
   CheckCanRunGui