[U-Boot-Users] [PATCH] TFTP: add host ip addr support

[Wolfgang Denk]

In message <478E68C6.8070309 at gmail.com> you wrote:
>
> > But I diaagree about strncpy because you need to known the size of
> > the string and we know it only when we use the default_filename otherwise
> > we need to strlen and in this strcpy do every thing itself.
> >
> >   
> strncpy copies AT MOST 'n' bytes.

...and doesn't necessarily NUL-terminate.

> #define MAX_FILE_NAME_LEN 80
> static char tftp_filename[MAX_FILE_NAME_LEN];
> 
> strncpy(tftp_filename, str, MAX_FILE_NAME_LEN);
> 
> Standard buffer overrun protection.

...only if you make sure that tftp_filename[] gets terminated
independent of the length; otherwise you fix the problem when writing
the srting but create one when reading it.

Best regards,

Wolfgang Denk

-- 
DENX Software Engineering GmbH,     MD: Wolfgang Denk & Detlev Zundel
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Every program has at least one bug and can be shortened by  at  least
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