Move readline to the readline/readline subdirectory

readline turns out to be a bit of a stumbling block for the project to
move gdbsupport (and then gdbserver) to the top-level.

The issue is that readline headers are intended to be included with
names like "readline/readline.h".  To support this, gdb effectively
adds a -I option pointing to the top-level source directory -- but,
importantly, this option is not used when the system readline is used.

For gdbsupport, a -I option like this would always be needed, but that
in turn would break the system readline case.  This was PR build/17077,
fixed in commit a8a5dbcab8df0b3a9e04745d4fe8d64740acb323.

Previously, we had discussed this on the gdb-patches list in terms of
removing readline from the tree

    https://sourceware.org/ml/gdb-patches/2019-09/msg00317.html

However, Eli expressed some concerns, and Joel did as well (off-list).

Given those concerns, and the fact that a patch-free local readline is
relatively new in gdb (it was locally patched for years), I changed my
mind and decided to handle this situation by moving the readline
sources down a level.

That is, upstream readline is now in readline/readline, and the
top-level readline directory just contains the minimal configury
needed to build that.

This fixes the problem because, when gdb unconditionally adds a
-I$(top_srcdir), this will not find readline headers.  A separate -I
will be needed instead, which is exactly what's needed for
--with-system-readline.

gdb/ChangeLog
2019-10-23  Tom Tromey  <tom@tromey.com>

	* Makefile.in (READLINE_DIR): Update.

gdb/doc/ChangeLog
2019-10-23  Tom Tromey  <tom@tromey.com>

	* Makefile.in (READLINE_DIR): Update.

readline/ChangeLog
2019-10-23  Tom Tromey  <tom@tromey.com>

	Move old contents to readline/ subdirectory.
	* aclocal.m4, configure, configure.ac, .gitignore, Makefile.am,
	Makefile.in, README: New files.

Change-Id: Ice156a2ee09ea68722b48f64d97146d7428ea9e4

1 files changed, 0 insertions, 49 deletions

diff --git a/readline/xfree.c b/readline/xfree.c
deleted file mode 100644
index c199b29..0000000
--- a/readline/xfree.c
+++ /dev/null
@@ -1,49 +0,0 @@
-/* xfree.c -- safe version of free that ignores attempts to free NUL */
-
-/* Copyright (C) 1991-2010,2017 Free Software Foundation, Inc.
-
-   This file is part of the GNU Readline Library (Readline), a library
-   for reading lines of text with interactive input and history editing.      
-
-   Readline is free software: you can redistribute it and/or modify
-   it under the terms of the GNU General Public License as published by
-   the Free Software Foundation, either version 3 of the License, or
-   (at your option) any later version.
-
-   Readline is distributed in the hope that it will be useful,
-   but WITHOUT ANY WARRANTY; without even the implied warranty of
-   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
-   GNU General Public License for more details.
-
-   You should have received a copy of the GNU General Public License
-   along with Readline.  If not, see <http://www.gnu.org/licenses/>.
-*/
-
-#define READLINE_LIBRARY
-
-#if defined (HAVE_CONFIG_H)
-#include <config.h>
-#endif
-
-#if defined (HAVE_STDLIB_H)
-#  include <stdlib.h>
-#else
-#  include "ansi_stdlib.h"
-#endif /* HAVE_STDLIB_H */
-
-#include "xmalloc.h"
-
-/* **************************************************************** */
-/*								    */
-/*		   Memory Deallocation.				    */
-/*								    */
-/* **************************************************************** */
-
-/* Use this as the function to call when adding unwind protects so we
-   don't need to know what free() returns. */
-void
-xfree (PTR_T string)
-{
-  if (string)
-    free (string);
-}