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Re: Small problem with Remote Protocol register fetching.


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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