Re: [Qemu-devel] [PATCH for-4.0 v4 2/4] refactor load_image_size

[Stefano Garzarella]

On Mon, Dec 24, 2018 at 3:16 AM Li Zhijian <address@hidden> wrote:
>
>
> On 12/22/18 00:12, Michael S. Tsirkin wrote:
> > On Thu, Dec 06, 2018 at 10:32:11AM +0800, Li Zhijian wrote:
> >> Don't expect read(2) can always read as many as it's told.
> >>
> >> Signed-off-by: Li Zhijian <address@hidden>
> >> Reviewed-by: Richard Henderson <address@hidden>
> > This is more a theoretical bugfix than a refactoring right?
>
> Yes， it does.
>
> how about change the title to : "enhance reading on load_image_size()" or such

Maybe something like this: "hw/core/loader.c: Read as long as possible
in load_image_size()"

Reviewed-by: Stefano Garzarella <address@hidden>

>
> Thanks
> Zhijian
>
>
> >
> >> ---
> >> V4: add reviewed-by tag
> >> ---
> >>   hw/core/loader.c | 11 +++++------
> >>   1 file changed, 5 insertions(+), 6 deletions(-)
> >>
> >> diff --git a/hw/core/loader.c b/hw/core/loader.c
> >> index fa41842..9cbceab 100644
> >> --- a/hw/core/loader.c
> >> +++ b/hw/core/loader.c
> >> @@ -77,21 +77,20 @@ int64_t get_image_size(const char *filename)
> >>   ssize_t load_image_size(const char *filename, void *addr, size_t size)
> >>   {
> >>       int fd;
> >> -    ssize_t actsize;
> >> +    ssize_t actsize, l = 0;
> >>
> >>       fd = open(filename, O_RDONLY | O_BINARY);
> >>       if (fd < 0) {
> >>           return -1;
> >>       }
> >>
> >> -    actsize = read(fd, addr, size);
> >> -    if (actsize < 0) {
> >> -        close(fd);
> >> -        return -1;
> >> +    while ((actsize = read(fd, addr + l, size - l)) > 0) {
> >> +        l += actsize;
> >>       }
> >> +
> >>       close(fd);
> >>
> >> -    return actsize;
> >> +    return actsize < 0 ? -1 : l;
> >>   }
> >>
> >>   /* read()-like version */
> >> --
> >> 2.7.4
> >
> >
> >
> --
> Best regards.
> Li Zhijian (8528)
>
>
>


-- 
Stefano Garzarella
Red Hat