[PATCH] read_file: Make it work on tftp servers which do not pass size

[Alexander Aring]

Hi Sascha,

only a very small hint.

On Wed, Jun 19, 2013 at 10:58:48PM +0200, Sascha Hauer wrote:
> Some tftp servers (for example netkit-tftp) do not pass the filesize.
> Add a workaround for read_file which reads the file into a temporary
> file which then is copied to a buffer.
> 
> Signed-off-by: Sascha Hauer <s.hauer at pengutronix.de>
> ---
>  fs/fs.c      | 18 ++++++++++++++++++
>  fs/tftp.c    |  5 ++++-
>  include/fs.h |  2 ++
>  3 files changed, 24 insertions(+), 1 deletion(-)
> 
> diff --git a/fs/fs.c b/fs/fs.c
> index dc3a6e3..7046f2c 100644
> --- a/fs/fs.c
> +++ b/fs/fs.c
> @@ -38,10 +38,21 @@ void *read_file(const char *filename, size_t *size)
>  	int fd;

...

>  
>  	tftp_do_close(priv);
>  
> diff --git a/include/fs.h b/include/fs.h
> index 8ff7300..fa6a8da 100644
> --- a/include/fs.h
> +++ b/include/fs.h
> @@ -147,6 +147,8 @@ int protect(int fd, size_t count, unsigned long offset, int prot);
>  int protect_file(const char *file, int prot);
>  void *memmap(int fd, int flags);
>  
> +#define FILESIZE_MAX	((size_t)-1)

The type of st_size in struct stat is loff_t. I check this and
((size_t)-1) is different than ((loff_t)-1), so I think we need to cast
to loff_t. Maybe it's better to use a define from limits.h, but we don't
have some header file like this.