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Date: Wed, 30 Mar 2022 13:22:11 +0000
From: Lancelot SIX <lsix@lancelotsix.com>
To: Pedro Alves <pedro@palves.net>
Cc: gdb-patches@sourceware.org
Subject: Re: [PATCH 2/3] gdbserver/linux: Access memory even if threads are
 running
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> +/* Helper for read_memory/write_memory using /proc/PID/mem.  Because
> +   we can use a single read/write call, this can be much more
> +   efficient than banging away at PTRACE_PEEKTEXT.  Also, unlike
> +   PTRACE_PEEKTEXT/PTRACE_POKETEXT, this works with running threads.
> +   One an only one of READBUF and WRITEBUF is non-null.  If READBUF is
> +   not null, then we're reading, otherwise we're writing.  */

Hi,

Seems to me that this property can be asserted.  WDYT?

Something like

    gdb_assert ((readbuf == nullptr) != (writebuf == nullptr));

should do.

Best,
Lancelot.

> +
> +static int
> +proc_xfer_memory (CORE_ADDR memaddr, unsigned char *readbuf,
> +		  const gdb_byte *writebuf, int len)