Small problem with Remote Protocol register fetching.

Michael Snyder msnyder@redhat.com
Tue Jun 15 18:52:00 GMT 2004


Steven Johnson wrote:
> Registers in the remote protocol are Hex Encoded.  Hex encoded values 
> can have (as far as I can tell, valid values of '0'-'9','a'-'f','A'-'F' 
> and ('x' for registers). the problem is that register packets that have 
> an upper case 'A'-'F' in the first location are junked as being bad 
> packets, when their is nothing wrong.  And then GDB ends up in an 
> infinite comms loop, trying to recover.
> 
> The attached patch allows Hex Encoded values to include upper case 
> letters (in the case of fetching registers) without causing the packet 
> handling to fail.
> 
> I wasnt sure if 'X' should also be allowable, seems like it should, but 
> i dont know for sure, so havent changed it.
> 
> Steven Johnson

What Andrew said, but OTOH, this is certainly not an intrusive change.
Steven, what remote target are you seeing this with?

[Someone will say "but then we'll have to make sure that we consistantly
accept upper case throughout, and I agree that's a little more intrusive]


> ------------------------------------------------------------------------
> 
> diff -p -u -r clean-src/insight-6.1/gdb/frame.c mod-src/insight-6.1/gdb/frame.c
> diff -p -u -r clean-src/insight-6.1/gdb/remote.c mod-src/insight-6.1/gdb/remote.c
> --- clean-src/insight-6.1/gdb/remote.c	2004-02-26 06:41:00.000000000 +1000
> +++ mod-src/insight-6.1/gdb/remote.c	2004-06-15 16:36:53.000000000 +1000
> @@ -3278,6 +3278,7 @@ remote_fetch_registers (int regnum)
>       and try to fetch another packet to read.  */
>    while ((buf[0] < '0' || buf[0] > '9')
>  	 && (buf[0] < 'a' || buf[0] > 'f')
> +	 && (buf[0] < 'A' || buf[0] > 'F')
>  	 && buf[0] != 'x')	/* New: unavailable register value */
>      {
>        if (remote_debug)




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