Il 21/09/2012 10:33, Kevin Wolf ha scritto:
>> > + /* could not reopen the file handle, so fall back to opening
>> > + * new file (CreateFile) */
>> > + if (raw_s->hfile == INVALID_HANDLE_VALUE) {
>> > + raw_s->hfile = CreateFile(state->bs->filename, access_flags,
>> > + FILE_SHARE_READ, NULL, OPEN_EXISTING,
>> > + overlapped, NULL);
>> > + if (raw_s->hfile == INVALID_HANDLE_VALUE) {
>> > + /* this could happen because the access_flags requested are
>> > + * incompatible with the existing share mode of s->hfile,
>> > + * so our only option now is to close s->hfile, and try again.
>> > + * This could end badly */
>> > + CloseHandle(s->hfile);
> How common is this case?
>
> We do have another option, namely not reopen at all and return an error.
> Of course, this only makes sense if it doesn't mean that we almost never
> succeed.
Probably pretty common since we specify FILE_SHARE_READ for the sharing
mode, meaning that "subsequent open operations on a file or device are
only able to request read access".
I would change it to FILE_SHARE_READ|FILE_SHARE_WRITE and remove this code.
Paolo
