Sync readline/ to version 7.0 alpha

This patch syncs our upstream copy of readline from version 6.2 to the
latest version, 7.0 alpha (released July 10 2015).

I essentially copied what was done the last time readline was synced,
when Jan updated to readline 6.2 in 2011:
http://sourceware.org/ml/gdb-patches/2011-05/msg00003.html

Procedure:

1. I extracted the readline-7.0-alpha tarball on top of readline/.
2. I deleted all the new files under doc/ that were deliberately omitted
   before.
3. I regenerated readline/configure and readline/examples/rlfe/configure
   using autoconf 2.64.  No other configure files need regenerating.
4. I updated the function gdb_printable_part in completer.c with a
   trivial change made to the readline function it is based off of,
   printable_part in readline/complete.c.  There is more work to be done in
   completer.c to sync it with readline/complete.c, but it is non-trivial
   and should probably be done separately anyway.

Local patches that had to be reapplied:

    None.  readline 7.0 alpha contains all of our local readline
    patches.

New files in readline/:

    colors.{c,h}
    examples/{hist_erasedups,hist_purgecmd,rl-callbacktest,rlbasic}.c
    parse-colors.{c,h}
    readline.pc.in
    configure.ac

Deleted files in readline/:

    configure.in

Regressions:

After the sync there is one testsuite regression, the test
"signal SIGINT" in gdb.gdb/selftest.exp which now FAILs.  Previously,
the readline 6.2 SIGINT handler would temporarily reinstall the
underlying application's SIGINT handler and immediately re-raise SIGINT
so that the orginal handler gets invoked.  But now (since readline 6.3)
its SIGINT handler does not re-raise SIGINT or directly invoke the
original handler; it now sets a flag marking that SIGINT was raised, and
waits until readline explicitly has control to call the application's
SIGINT handler.  Anyway, because SIGINT is no longer re-raised from
within readline's SIGINT handler, doing "signal SIGINT" with a stopped
inferior gdb process will no longer resume and then immediately stop the
process (since there is no 2nd SIGINT to immediately catch).  Instead,
the inferior gdb process will now just print "Quit" and continue to run.
So with this commit, this particular test case is adjusted to reflect
this change in behavior (we now have to send a 2nd SIGINT manually to
stop it).

Aside from this one testsuite regression, I personally noticed no
regression in user-visible behavior.  Though I only tested on x86_64
and on i686 Debian Stretch.

Getting this kind of change in at the start of the GDB 7.11 development
cycle will allow us to get a lot of passive testing from developers and
from bleeding-edge users.

readline/ChangeLog.gdb:

	Import readline 7.0 alpha
	* configure: Regenerate.
	* examples/rlfe/configure: Regenerate.

gdb/ChangeLog:

	* completer.c (gdb_printable_part): Sync with readline function
	it is based off of.

gdb/testsuite/ChangeLog:

	* gdb.gdb/selftest.exp (test_with_self): Update test to now
	expect the GDB inferior to no longer immediately stop after
	being resumed with "signal SIGINT".

1 files changed, 231 insertions, 0 deletions

diff --git a/readline/CHANGES b/readline/CHANGES
index 9d58988..8436701 100644
--- a/readline/CHANGES
+++ b/readline/CHANGES
@@ -1,3 +1,234 @@
+This document details the changes between this version, readline-7.0, and the
+previous version, readline-6.3.
+
+1.  Changes to Readline
+
+a.  A bug that caused vi-mode `.' to be unable to redo `c', `d', and `y'
+    commands with modifiers was fixed.
+
+b.  Fixed a bug that caused callback mode to dump core when reading a
+    multiple-key sequence (e.g., arrow keys).
+
+c.  Fixed a bug that caused the redisplay code to erase some of the line when
+    using horizontal scrolling with incremental search.
+
+d.  Readline's input handler now performs signal processing if read(2) is
+    interrupted by SIGALRM or SIGVTALRM.
+
+e.  Fixed a problem with revert-all-at-newline freeing freed memory.
+
+f.  Clarified the documentation for the history_quotes_inhibit_expansion
+    variable to note that it inhibits scanning for the history comment
+    character and that it only affects double-quoted strings.
+
+g.  Fixed an off-by-one error in the prompt printed when performing searches.
+
+h.  Use pselect(2), if available, to wait for input before calling read(2), so
+    a SIGWINCH can interrupt it, since it doesn't interrupt read(2).
+
+i.  Some memory leaks caused by signals interrupting filename completion have
+    been fixed.
+
+j.  Reading EOF twice on a non-empty line causes EOF to be returned, rather
+    than the partial line.  This can cause partial lines to be executed on
+    SIGHUP, for example.
+
+k.  Fixed a bug concerning deleting multibyte characters from the search
+    string while performing an incremental search.
+
+l.  Fixed a bug with tilde expanding directory names in filename completion.
+
+m.  Fixed a bug that did not allow binding sequences beginning with a `\'.
+
+n.  Fixed a redisplay bug involving incorrect line wrapping when the prompt
+    contains a multibyte character in the last screen column.
+
+o.  Fixed a bug that caused history expansion to disregard characters that are
+    documented to delimit a history event specifier without requiring `:'.
+
+p.  Fixed a bug that could cause reading past the end of a string when reading
+    the value when binding the set of isearch terminators.
+
+q.  Fixed a bug that caused readline commands that depend on knowing which  
+    key invoked them to misbehave when dispatching key sequences that are
+    prefixes of other key bindings. 
+
+r.  Paren matching now works in vi insert mode.
+
+2.  New Features in Readline
+
+a.  The history truncation code now uses the same error recovery mechansim as
+    the history writing code, and restores the old version of the history file
+    on error.  The error recovery mechanism handles symlinked history files.
+
+b.  There is a new bindable variable, `enable-bracketed-paste', which enables
+    support for a terminal's bracketed paste mode.
+
+c.  The editing mode indicators can now be strings and are user-settable
+    (new `emacs-mode-string', `vi-cmd-mode-string' and `vi-ins-mode-string'
+    variables).  Mode strings can contain invisible character sequences.
+    Setting mode strings to null strings restores the defaults.
+
+d.  Prompt expansion adds the mode string to the last line of a multi-line
+    prompt (one with embedded newlines).
+
+e.  There is a new bindable variable, `colored-completion-prefix', which, if
+    set, causes the common prefix of a set of possible completions to be
+    displayed in color.
+
+f.  There is a new bindable command `vi-yank-pop', a vi-mode version of emacs-
+    mode yank-pop.
+
+g.  The redisplay code underwent several efficiency improvements for multibyte
+    locales.
+
+h.  The insert-char function attempts to batch-insert all pending typeahead
+    that maps to self-insert, as long as it is coming from the terminal.
+
+i.  rl_callback_sigcleanup: a new application function that can clean up and
+    unset any state set by readline's callback mode.  Intended to be used
+    after a signal.
+
+-------------------------------------------------------------------------------
+This document details the changes between this version, readline-6.3, and the
+previous version, readline-6.2.
+
+1.  Changes to Readline
+
+a.  Fixed a bug that did not allow the `dd', `cc', or `yy' vi editing mode
+    commands to work on the entire line.
+
+b.  Fixed a bug that caused redisplay problems with prompts longer than 128
+    characters and history searches.
+
+c.  Fixed a bug that caused readline to try and run code to modify its idea
+    of the screen size in a signal handler context upon receiving a SIGWINCH.
+
+d.  Fixed a bug that caused the `meta' key to be enabled beyond the duration
+    of an individual call top readline().
+    
+e.  Added a workaround for a wcwidth bug in Mac OS X that caused readline's
+    redisplay to mishandle zero-width combining characters.
+
+f.  Fixed a bug that caused readline to `forget' part of a key sequence when
+    a multiple-key sequence caused it to break out of an incremental search.
+
+g.  Fixed bugs that caused readline to execute code in a signal handler
+    context if interrupted while reading from the file system during completion.
+
+h.  Fixed a bug that caused readline to `forget' part of a key sequence when
+    reading an unbound multi-character key sequence.
+
+i.  Fixed a bug that caused Readline's signal handlers to be installed beyond
+    the bounds of a single call to readline().
+
+j.  Fixed a bug that caused the `.' command to not redo the most recent `R'
+    command in vi mode.
+
+k.  Fixed a bug that caused ignoring case in completion matches to result in
+    readline using the wrong match.
+
+l.  Paren matching now works in vi insert mode.
+
+m.  Fix menu-completion to make show-all-if-ambiguous and menu-complete-display-prefix
+    work together.
+
+n.  Fixed a bug that didn't allow the `cc', `dd', or `yy' commands to be redone
+    in vi editing mode.
+
+o.  Fixed a bug that caused the filename comparison code to not compare
+    multibyte characters correctly when using case-sensitive or case-mapping
+    comparisons.
+
+p.  Fixed the input reading loop to call the input hook function only when there
+    is no terminal input available.
+
+q.  Fixed a bug that caused binding a macro to a multi-character key sequence
+    where the sequence and macro value share a common prefix to not perform
+    the macro replacement.
+
+r.  Fixed several redisplay errors with multibyte characters and prompts
+    containing invisible characters when using horizontal scrolling.
+
+s.  Fixed a bug that caused redisplay errors when trying to overwrite
+    existing characters using multibyte characters.
+
+t.  Fixed a bug in vi mode that caused the arrow keys to set the saved last
+    vi-mode command to the wrong value.
+
+u.  Fixed a bug that caused double-quoted strings to be scanned incorrectly
+    when being used as the value of a readline variable assignment.
+
+v.  Fixed a bug with vi mode that prevented `.' from repeating a command
+    entered on a previous line (command).
+
+w.  Fixed a bug that could cause completion to core dump if it was interrupted
+    by a signal.
+
+x. Fixed a bug that could cause readline to crash and seg fault attempting to
+   expand an empty history entry.
+
+y. Fixed a bug that caused display problems with multi-line prompts containing
+   invisible characters on multiple lines.
+   
+z. Fixed a bug that caused effects made by undoing changes to a history line to
+   be discarded.
+
+2.  New Features in Readline
+
+a.  Readline is now more responsive to SIGHUP and other fatal signals when
+    reading input from the terminal or performing word completion but no
+    longer attempts to run any not-allowable functions from a signal handler
+    context.
+
+b.  There are new bindable commands to search the history for the string of
+    characters between the beginning of the line and the point
+    (history-substring-search-forward, history-substring-search-backward)
+
+c.  Readline allows quoted strings as the values of variables when setting
+    them with `set'.  As a side effect, trailing spaces and tabs are ignored
+    when setting a string variable's value.
+
+d.  The history library creates a backup of the history file when writing it
+    and restores the backup on a write error.
+
+e.  New application-settable variable: rl_filename_stat_hook: a function called
+    with a filename before using it in a call to stat(2).  Bash uses it to
+    expand shell variables so things like $HOME/Downloads have a slash
+    appended.
+
+f.  New bindable function `print-last-kbd-macro', prints the most-recently-
+    defined keyboard macro in a reusable format.
+
+g.  New user-settable variable `colored-stats', enables use of colored text
+    to denote file types when displaying possible completions (colored analog
+    of visible-stats).
+
+h.  New user-settable variable `keyseq-timout', acts as an inter-character
+    timeout when reading input or incremental search strings.
+
+i.  New application-callable function: rl_clear_history. Clears the history list
+    and frees all readline-associated private data.
+
+j.  New user-settable variable, show-mode-in-prompt, adds a characters to the
+    beginning of the prompt indicating the current editing mode.
+
+k.  New application-settable variable: rl_input_available_hook; function to be
+    called when readline needs to check whether there is data available on its
+    input source.  The default hook checks rl_instream.
+
+l.  Readline calls an application-set event hook (rl_signal_event_hook) after
+    it gets a signal while reading input (read returns -1/EINTR but readline    
+    does not handle the signal immediately) to allow the application to handle
+    or otherwise note it.  Not currently called for SIGHUP or SIGTERM.
+    
+m.  If the user-settable variable `history-size' is set to a value less than
+    0, the history list size is unlimited.
+
+n.  When creating shared libraries on Mac OS X, the pathname written into the
+    library (install_name) no longer includes the minor version number.
+
+-------------------------------------------------------------------------------
 This document details the changes between this version, readline-6.2,
 and the previous version, readline-6.1.