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, 78 deletions

diff --git a/readline/examples/rlfe/README b/readline/examples/rlfe/README
deleted file mode 100644
index 9e1f689..0000000
--- a/readline/examples/rlfe/README
+++ /dev/null
@@ -1,78 +0,0 @@
-rlfe (ReadLine Front-End) is a "universal wrapper" around readline.
-You specify an interactive program to run (typically a shell), and
-readline is used to edit input lines.
-
-There are other such front-ends; what distinguishes this one is that
-it monitors the state of the inferior pty, and if the inferior program
-switches its terminal to raw mode, then rlfe passes your characters
-through directly.  This basically means you can run your entire
-session (including bash and terminal-mode emacs) under rlfe.
-
-FEATURES
-
-* Can use all readline commands (and history) in commands that
-read input lines in "canonical mode" - even 'cat'!
-
-* Automatically switches between "readline-editing mode" and "raw mode"
-depending on the terminal mode.  If the inferior program invokes
-readline itself, it will do its own line editing.  (The inferior
-readline will not know about rlfe, and it will have its own history.)
-You can even run programs like 'emavs -nw' and 'vi' under rlfe.
-The goal is you could leave rlfe always on without even knowing
-about it.  (We're not quite there, but it works tolerably well.)
-
-* The input line (after any prompt) is changed to bold-face.
-
-INSTALL
-
-The usual: ./configure && make && make install
-
-Note so far rlfe has only been tested on GNU Linux (Fedora Core 2)
-and Mac OS X (10.3).
-
-This assumes readline header files and libraries are in the default
-places.  If not, you can create a link named readline pointing to the
-readline sources.  To link with libreadline.a and libhistory.a
-you can copy or link them, or add LDFLAGS='-/path/to/readline' to
-the make command-line.
-
-USAGE
-
-Just run it.  That by default runs bash.  You can run some other
-command by giving it as command-line arguments.
-
-There are a few tweaks:  -h allows you to name the history file,
-and -s allows you to specify its size.  It default to "emacs" mode,
-but if the the environment variable EDITOR is set to "vi" that
-mode is chosen.
-
-ISSUES
-
-* The mode switching depends on the terminal mode set by the inferior
-program.  Thus ssh/telnet/screen-type programs will typically be in
-raw mode, so rlfe won't be much use, even if remote programs run in
-canonical mode.  The work-around is to run rlfe on the remote end.
-
-* Echo supression and prompt recognition are somewhat fragile.
-(A protocol so that the o/s tty code can reliably communicate its
-state to rlfe could solve this problem, and the previous one.)
-
-* See the intro to rlfe.c for more notes.
-
-* Assumes a VT100-compatible terminal, though that could be generalized
-if anybody cares.
-
-* Requires ncurses.
-
-* It would be useful to integrate rlfe's logic in a terminal emulator.
-That would make it easier to reposition the edit position with a mouse,
-integrate cut-and-paste with the system clipboard, and more robustly
-handle escape sequence and multi-byte characters more robustly.
-
-AUTHOR
-
-Per Bothner <per@bothner.com>
-
-LICENSE
-
-GPL.