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, 360 deletions

diff --git a/readline/callback.c b/readline/callback.c
deleted file mode 100644
index a466cf9..0000000
--- a/readline/callback.c
+++ /dev/null
@@ -1,360 +0,0 @@
-/* callback.c -- functions to use readline as an X `callback' mechanism. */
-
-/* Copyright (C) 1987-2017 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
-
-#include "rlconf.h"
-
-#if defined (READLINE_CALLBACKS)
-
-#include <sys/types.h>
-
-#ifdef HAVE_STDLIB_H
-#  include <stdlib.h>
-#else
-#  include "ansi_stdlib.h"
-#endif
-
-#include <stdio.h>
-
-/* System-specific feature definitions and include files. */
-#include "rldefs.h"
-#include "readline.h"
-#include "rlprivate.h"
-#include "xmalloc.h"
-
-/* Private data for callback registration functions.  See comments in
-   rl_callback_read_char for more details. */
-_rl_callback_func_t *_rl_callback_func = 0;
-_rl_callback_generic_arg *_rl_callback_data = 0;
-
-/* Applications can set this to non-zero to have readline's signal handlers
-   installed during the entire duration of reading a complete line, as in
-   readline-6.2.  This should be used with care, because it can result in
-   readline receiving signals and not handling them until it's called again
-   via rl_callback_read_char, thereby stealing them from the application.
-   By default, signal handlers are only active while readline is active. */   
-int rl_persistent_signal_handlers = 0;
-
-/* **************************************************************** */
-/*								    */
-/*			Callback Readline Functions		    */
-/*								    */
-/* **************************************************************** */
-
-/* Allow using readline in situations where a program may have multiple
-   things to handle at once, and dispatches them via select().  Call
-   rl_callback_handler_install() with the prompt and a function to call
-   whenever a complete line of input is ready.  The user must then
-   call rl_callback_read_char() every time some input is available, and 
-   rl_callback_read_char() will call the user's function with the complete
-   text read in at each end of line.  The terminal is kept prepped
-   all the time, except during calls to the user's function.  Signal
-   handlers are only installed when the application calls back into
-   readline, so readline doesn't `steal' signals from the application.  */
-
-rl_vcpfunc_t *rl_linefunc;		/* user callback function */
-static int in_handler;		/* terminal_prepped and signals set? */
-
-/* Make sure the terminal is set up, initialize readline, and prompt. */
-static void
-_rl_callback_newline (void)
-{
-  rl_initialize ();
-
-  if (in_handler == 0)
-    {
-      in_handler = 1;
-
-      if (rl_prep_term_function)
-	(*rl_prep_term_function) (_rl_meta_flag);
-
-#if defined (HANDLE_SIGNALS)
-      if (rl_persistent_signal_handlers)
-	rl_set_signals ();
-#endif
-    }
-
-  readline_internal_setup ();
-  RL_CHECK_SIGNALS ();
-}
-
-/* Install a readline handler, set up the terminal, and issue the prompt. */
-void
-rl_callback_handler_install (const char *prompt, rl_vcpfunc_t *linefunc)
-{
-  rl_set_prompt (prompt);
-  RL_SETSTATE (RL_STATE_CALLBACK);
-  rl_linefunc = linefunc;
-  _rl_callback_newline ();
-}
-
-#if defined (HANDLE_SIGNALS)
-#define CALLBACK_READ_RETURN() \
-  do { \
-    if (rl_persistent_signal_handlers == 0) \
-      rl_clear_signals (); \
-    return; \
-  } while (0)
-#else
-#define CALLBACK_READ_RETURN() return
-#endif
-
-/* Read one character, and dispatch to the handler if it ends the line. */
-void
-rl_callback_read_char (void)
-{
-  char *line;
-  int eof, jcode;
-  static procenv_t olevel;
-
-  if (rl_linefunc == NULL)
-    {
-      _rl_errmsg ("readline_callback_read_char() called with no handler!");
-      abort ();
-    }
-
-  memcpy ((void *)olevel, (void *)_rl_top_level, sizeof (procenv_t));
-#if defined (HAVE_POSIX_SIGSETJMP)
-  jcode = sigsetjmp (_rl_top_level, 0);
-#else
-  jcode = setjmp (_rl_top_level);
-#endif
-  if (jcode)
-    {
-      (*rl_redisplay_function) ();
-      _rl_want_redisplay = 0;
-      memcpy ((void *)_rl_top_level, (void *)olevel, sizeof (procenv_t));
-      CALLBACK_READ_RETURN ();
-    }
-
-#if defined (HANDLE_SIGNALS)
-  /* Install signal handlers only when readline has control. */
-  if (rl_persistent_signal_handlers == 0)
-    rl_set_signals ();
-#endif
-
-  do
-    {
-      RL_CHECK_SIGNALS ();
-      if  (RL_ISSTATE (RL_STATE_ISEARCH))
-	{
-	  eof = _rl_isearch_callback (_rl_iscxt);
-	  if (eof == 0 && (RL_ISSTATE (RL_STATE_ISEARCH) == 0) && RL_ISSTATE (RL_STATE_INPUTPENDING))
-	    rl_callback_read_char ();
-
-	  CALLBACK_READ_RETURN ();
-	}
-      else if  (RL_ISSTATE (RL_STATE_NSEARCH))
-	{
-	  eof = _rl_nsearch_callback (_rl_nscxt);
-
-	  CALLBACK_READ_RETURN ();
-	}
-#if defined (VI_MODE)
-      /* States that can occur while in state VIMOTION have to be checked
-	 before RL_STATE_VIMOTION */
-      else if (RL_ISSTATE (RL_STATE_CHARSEARCH))
-	{
-	  int k;
-
-	  k = _rl_callback_data->i2;
-
-	  eof = (*_rl_callback_func) (_rl_callback_data);
-	  /* If the function `deregisters' itself, make sure the data is
-	     cleaned up. */
-	  if (_rl_callback_func == 0)	/* XXX - just sanity check */
-	    {
-	      if (_rl_callback_data)
-		{
-		  _rl_callback_data_dispose (_rl_callback_data);
-		  _rl_callback_data = 0;
-		}
-	    }
-
-	  /* Messy case where vi motion command can be char search */
-	  if (RL_ISSTATE (RL_STATE_VIMOTION))
-	    {
-	      _rl_vi_domove_motion_cleanup (k, _rl_vimvcxt);
-	      _rl_internal_char_cleanup ();
-	      CALLBACK_READ_RETURN ();	      
-	    }
-
-	  _rl_internal_char_cleanup ();
-	}
-      else if (RL_ISSTATE (RL_STATE_VIMOTION))
-	{
-	  eof = _rl_vi_domove_callback (_rl_vimvcxt);
-	  /* Should handle everything, including cleanup, numeric arguments,
-	     and turning off RL_STATE_VIMOTION */
-	  if (RL_ISSTATE (RL_STATE_NUMERICARG) == 0)
-	    _rl_internal_char_cleanup ();
-
-	  CALLBACK_READ_RETURN ();
-	}
-#endif
-      else if (RL_ISSTATE (RL_STATE_NUMERICARG))
-	{
-	  eof = _rl_arg_callback (_rl_argcxt);
-	  if (eof == 0 && (RL_ISSTATE (RL_STATE_NUMERICARG) == 0) && RL_ISSTATE (RL_STATE_INPUTPENDING))
-	    rl_callback_read_char ();
-	  /* XXX - this should handle _rl_last_command_was_kill better */
-	  else if (RL_ISSTATE (RL_STATE_NUMERICARG) == 0)
-	    _rl_internal_char_cleanup ();
-
-	  CALLBACK_READ_RETURN ();
-	}
-      else if (RL_ISSTATE (RL_STATE_MULTIKEY))
-	{
-	  eof = _rl_dispatch_callback (_rl_kscxt);	/* For now */
-	  while ((eof == -1 || eof == -2) && RL_ISSTATE (RL_STATE_MULTIKEY) && _rl_kscxt && (_rl_kscxt->flags & KSEQ_DISPATCHED))
-	    eof = _rl_dispatch_callback (_rl_kscxt);
-	  if (RL_ISSTATE (RL_STATE_MULTIKEY) == 0)
-	    {
-	      _rl_internal_char_cleanup ();
-	      _rl_want_redisplay = 1;
-	    }
-	}
-      else if (_rl_callback_func)
-	{
-	  /* This allows functions that simply need to read an additional
-	     character (like quoted-insert) to register a function to be
-	     called when input is available.  _rl_callback_data is a
-	     pointer to a struct that has the argument count originally
-	     passed to the registering function and space for any additional
-	     parameters.  */
-	  eof = (*_rl_callback_func) (_rl_callback_data);
-	  /* If the function `deregisters' itself, make sure the data is
-	     cleaned up. */
-	  if (_rl_callback_func == 0)
-	    {
-	      if (_rl_callback_data) 	
-		{
-		  _rl_callback_data_dispose (_rl_callback_data);
-		  _rl_callback_data = 0;
-		}
-	      _rl_internal_char_cleanup ();
-	    }
-	}
-      else
-	eof = readline_internal_char ();
-
-      RL_CHECK_SIGNALS ();
-      if (rl_done == 0 && _rl_want_redisplay)
-	{
-	  (*rl_redisplay_function) ();
-	  _rl_want_redisplay = 0;
-	}
-
-      if (rl_done)
-	{
-	  line = readline_internal_teardown (eof);
-
-	  if (rl_deprep_term_function)
-	    (*rl_deprep_term_function) ();
-#if defined (HANDLE_SIGNALS)
-	  rl_clear_signals ();
-#endif
-	  in_handler = 0;
-	  (*rl_linefunc) (line);
-
-	  /* If the user did not clear out the line, do it for him. */
-	  if (rl_line_buffer[0])
-	    _rl_init_line_state ();
-
-	  /* Redisplay the prompt if readline_handler_{install,remove}
-	     not called. */
-	  if (in_handler == 0 && rl_linefunc)
-	    _rl_callback_newline ();
-	}
-    }
-  while (rl_pending_input || _rl_pushed_input_available () || RL_ISSTATE (RL_STATE_MACROINPUT));
-
-  CALLBACK_READ_RETURN ();
-}
-
-/* Remove the handler, and make sure the terminal is in its normal state. */
-void
-rl_callback_handler_remove (void)
-{
-  rl_linefunc = NULL;
-  RL_UNSETSTATE (RL_STATE_CALLBACK);
-  RL_CHECK_SIGNALS ();
-  if (in_handler)
-    {
-      in_handler = 0;
-      if (rl_deprep_term_function)
-	(*rl_deprep_term_function) ();
-#if defined (HANDLE_SIGNALS)
-      rl_clear_signals ();
-#endif
-    }
-}
-
-_rl_callback_generic_arg *
-_rl_callback_data_alloc (int count)
-{
-  _rl_callback_generic_arg *arg;
-
-  arg = (_rl_callback_generic_arg *)xmalloc (sizeof (_rl_callback_generic_arg));
-  arg->count = count;
-
-  arg->i1 = arg->i2 = 0;
-
-  return arg;
-}
-
-void
-_rl_callback_data_dispose (_rl_callback_generic_arg *arg)
-{
-  xfree (arg);
-}
-
-/* Make sure that this agrees with cases in rl_callback_read_char */
-void
-rl_callback_sigcleanup (void)
-{
-  if (RL_ISSTATE (RL_STATE_CALLBACK) == 0)
-    return;
-
-  if (RL_ISSTATE (RL_STATE_ISEARCH))
-    _rl_isearch_cleanup (_rl_iscxt, 0);
-  else if (RL_ISSTATE (RL_STATE_NSEARCH))
-    _rl_nsearch_cleanup (_rl_nscxt, 0);
-  else if (RL_ISSTATE (RL_STATE_VIMOTION))
-    RL_UNSETSTATE (RL_STATE_VIMOTION);
-  else if (RL_ISSTATE (RL_STATE_NUMERICARG))
-    {
-      _rl_argcxt = 0;
-      RL_UNSETSTATE (RL_STATE_NUMERICARG);
-    }
-  else if (RL_ISSTATE (RL_STATE_MULTIKEY))
-    RL_UNSETSTATE (RL_STATE_MULTIKEY);
-  if (RL_ISSTATE (RL_STATE_CHARSEARCH))
-    RL_UNSETSTATE (RL_STATE_CHARSEARCH);
-
-  _rl_callback_func = 0;
-}
-#endif