Re: [PATCH setup 2/2] List and offer to kill processes preventing a file from being written

[Jon TURNEY <jon dot turney at dronecode dot org dot uk>]

On 07/02/2013 05:06, Christopher Faylor wrote:
> On Wed, Feb 06, 2013 at 08:03:03PM +0000, Jon TURNEY wrote:
>> - Enumerate processes preventing a file from being written
>> - Replace the MessageBox reporting an in-use file with a DialogBox reporting the
>> in-use file and the processes which are using that file
>> - Offer to kill processes which have files open, trying /usr/bin/kill with SIGTERM,
>> then SIGKILL, then TerminateProcess
>>
>> v2:
>> - Use TerminateProcess directly, rather than using kill -f, so we will work even
>> if kill doesn't
>> - Fix formatting: spaces before parentheses for functions and macros
> 
> Thanks for doing this.  I know that the setup source code doesn't follow this
> rule consistently.
> 
> Please check in.  This looks like a really nice change.

Unfortunately, this change seems to have a few problems (See [1]):  If we
can't enumerate the processes which are preventing a file from being written,
or some other error occurs which archive::extract_file() doesn't know how to
report (e.g. disk full), the user is presented with the dialog with an empty
process list, and it's unclear how they should proceed (Ideally finding the
processes and stopping them themselves, as before...)

(In testing, on my W7 x86_64 system, it seems that service processes using a
file we want to replace could not be listed, even by an Adminstrator account.
 I'm not sure if it's possible to do anything about that or not...)

I couldn't really come up with a good way to show this in the new
IDD_FILE_INUSE dialog, so attached is patch which restores the custom message
box which was used previously to ask 'retry or continue' , and uses that when
the process list is empty.

If in future archive::extract_file() learns how to report other conditions,
there's perhaps some re-factoring which can go on here so IDD_FILE_INUSE is
used when we know the error was a sharing violation, and this 'retry or
continue' custom message box can be used to handle generic errors.

[1] http://cygwin.com/ml/cygwin/2013-07/msg00483.html

2013-07-23  Jon TURNEY  <jon.turney@dronecode.org.uk>

	* install.cc (_custom_MessageBox): Restore custom message box.
	(installOne): If processList is empty, use the custom message box
	to ask if we should retry or continue.
	* res.rc (IDD_FILE_INUSE): Use IDCONTINUE for continue button, to be
	the same custom message box.

Attachment: inuse.patch
Description: Text document