commit bash-20151230 snapshot

CWRU/CWRU.chlog

@@ -10176,3 +10176,109 @@ lib/readline/isearch.c
 	- _rl_isearch_dispatch: after removing the only character from the
 	  search string with DEL, leaving the search string empty, don't match
 	  the previous line if we didn't have a match before
+
+				   12/22
+				   -----
+bashhist.c
+	- enable_history_list,remember_on_history: initialize to 0 instead of 1
+
+shell.c
+	- init_interactive,init_interactive_script: set enable_history_list and
+	  remember_on_history to 1 (defaults)
+
+				   12/23
+				   -----
+variables.c
+	- initialize_shell_variables: don't inherit PS4 from the environment
+	  if the shell is running with euid == 0; just reset it to `+'.  This
+	  is a known potential vulnerability, since PS4 expansion performs
+	  command substitution in the root shell's context before displaying
+	  it.  Discussion started by up201407890@alunos.dcc.fc.up.pt
+
+bashhist.c
+	- bash_history_reinit: initialize remember_on_history to the value of
+	  enable_history_list (set -o history).  Fixes bug reported by
+	  Stephane Chazelas <stephane.chazelas@gmail.com> with command-line
+	  option `-o history' not having any effect
+
+				   12/28
+				   -----
+lib/readline/{history.h,histfile.c}
+	- history_file_version: new int variable, reserved for future use
+	- history_multiline_entries: new int variable, can be set by the
+	  calling application to enable reading multi-line history entries
+	  from the history file (currently undocumented)
+
+lib/readline/history.c
+	- _hs_append_history_line: new function, append a line passed as an
+	  argument to a specified history entry, used to create multi-line
+	  history entries
+
+lib/readline/histfile.c
+	- read_history_range: implement a heuristic that temporarily sets the
+	  history comment character if the first line read from the history
+	  file looks like it has is a timestamp (#[:digit:]) so we can read
+	  timestamps from the history file properly.  Originally reported
+	  back in March 2015 by Christoph Anton Mitterer <calestyo@gmail.com>
+	- read_history_range: make sure history_multiline_entries is non-zero
+	  if the history file looks like it has timestamps
+	- read_history_range: if we think we have a history file with timestamps
+	  and we read more than one non-timestamp consecutive history lines,
+	  assume they are part of a single multi-line history entry and paste
+	  them together using _hs_append_history_line.  Feature most recently
+	  requested by james harvey <jamespharvey20@gmail.com>, also suggested
+	  by Christoph Anton Mitterer <calestyo@gmail.com>
+
+examples/loadables/setpgid.c
+	- setpgid: new loadable builtin, originally contributed by Jason
+	  Vas Dias <jason.vas.dias@gmail.com>
+
+				   12/29
+				   -----
+bashhist.c
+	- bash_history_inhibit_expansion: fix cases where a history expansion
+	  should be skipped because it's in a command or process substitution
+	  but there is another history expansion preceding the substitution
+	  on the command line.  Don't let the previous history expansion fool
+	  the function into saying the command substitution history expansion
+	  should be performed
+
+builtins/evalstring.c
+	- parse_prologue: always unwind-protect history_expansion_inhibited,
+	  since history expansion can be enabled in non-interactive shells,
+	  and calling eval once in a non-interactive shell inhibits history
+	  expansion forever even if `set -o histexpand' was run before the
+	  eval
+
+builtins/common.h
+	- SEVAL_NOHISTEXP: new flag for parse_and_execute/parse_string; means
+	  to not perform history expansion (decouple from SEVAL_NOHIST, which
+	  now means to not remember commands on history); changed all callers
+	  that had SEVAL_NOHIST to have SEVAL_NOHIST|SEVAL_NOHISTEXP
+
+builtins/evalstring.c
+	- parse_prologue: instead of calling bash_history_disable, set
+	  remember_on_history to 0 if SEVAL_NOHIST and history_expansion_inhibited
+	  to 1 if SEVAL_NOHISTEXP
+
+				   12/30
+				   -----
+subst.c
+	- skip_to_histexp: new function, a stripped-down version of skip_to_delim.
+	  Used to skip to the next unquoted instance of the history expansion
+	  character, handles peculiar quoting and command/process substitution
+	  requirements.  Better fix for bug reported by
+	  Zigmund.Ozean@zig-home.localdomain back in January, prompted by report
+	  from Keith Thompson <keithsthompson@gmail.com>
+
+bashhist.c
+	- bash_history_inhibit_expansion: use skip_to_histexp instead of
+	  skip_to_delim
+
+subst.c
+	- parameter_brace_expand_rhs: if the rhs of an expansion is "$@" and
+	  IFS is null, we need to separate the (quoted) positional parameters
+	  in the returned word with a space, and mark the word as needing to
+	  be split on spaces (W_SPLITSPACE).  Fix for issues reported back in
+	  October 2014 as the result of an austin-group discussion, and just
+	  re-reported by Martijn Dekker <martijn@inlv.org>

MANIFEST

@@ -664,6 +664,7 @@ examples/loadables/necho.c	f
 examples/loadables/hello.c	f
 examples/loadables/print.c	f
 examples/loadables/realpath.c	f
+examples/loadables/setpgid.c	f
 examples/loadables/sleep.c	f
 examples/loadables/strftime.c	f
 examples/loadables/truefalse.c	f
@@ -921,6 +922,7 @@ tests/dollar-at-star3.sub	f
 tests/dollar-at-star4.sub	f
 tests/dollar-at-star5.sub	f
 tests/dollar-at-star6.sub	f
+tests/dollar-at-star7.sub	f
 tests/dollar-at1.sub	f
 tests/dollar-at2.sub	f
 tests/dollar-at3.sub	f
@@ -1020,6 +1022,8 @@ tests/herestr1.sub	f
 tests/histexp.tests	f
 tests/histexp1.sub	f
 tests/histexp2.sub	f
+tests/histexp3.sub	f
+tests/histexp4.sub	f
 tests/histexp.right	f
 tests/history.tests	f
 tests/history.right	f

bashhist.c

@@ -83,8 +83,8 @@ static struct ignorevar histignore =
 /* Non-zero means to remember lines typed to the shell on the history
    list.  This is different than the user-controlled behaviour; this
    becomes zero when we read lines from a file, for example. */
-int remember_on_history = 1;
-int enable_history_list = 1;	/* value for `set -o history' */
+int remember_on_history = 0;
+int enable_history_list = 0;	/* value for `set -o history' */
 
 /* The number of lines that Bash has added to this history session.  The
    difference between the number of the top element in the history list
@@ -99,6 +99,8 @@ int history_lines_in_file;
 /* Non-zero means do no history expansion on this line, regardless
    of what history_expansion says. */
 int history_expansion_inhibited;
+/* If non-zero, double quotes can quote the history expansion character. */
+int double_quotes_inhibit_history_expansion = 0;
 #endif
 
 /* With the old default, every line was saved in the history individually.
@@ -229,8 +231,18 @@ bash_history_inhibit_expansion (string, i)
 
   /* Make sure the history expansion should not be skipped by quoting or
      command/process substitution. */
-  else if ((t = skip_to_delim (string, 0, hx, SD_NOJMP|SD_HISTEXP)) > 0 && t > i)
-    return (1);
+  else if ((t = skip_to_histexp (string, 0, hx, SD_NOJMP|SD_HISTEXP)) > 0)
+    {
+      /* Skip instances of history expansion appearing on the line before
+	 this one. */
+      while (t < i)
+	{
+	  t = skip_to_histexp (string, t+1, hx, SD_NOJMP|SD_HISTEXP);
+	  if (t <= 0)
+	    return 0;
+	}
+      return (t > i);
+    }
   else
     return (0);
 }
@@ -252,9 +264,9 @@ bash_history_reinit (interact)
 {
 #if defined (BANG_HISTORY)
   history_expansion = interact != 0;
-  history_expansion_inhibited = 1;
+  history_expansion_inhibited = 1;	/* XXX */
 #endif
-  remember_on_history = enable_history_list = interact != 0;
+  remember_on_history = enable_history_list;
   history_inhibit_expansion_function = bash_history_inhibit_expansion;
 }
 
@@ -270,7 +282,7 @@ bash_history_disable ()
 void
 bash_history_enable ()
 {
-  remember_on_history = 1;
+  remember_on_history = enable_history_list = 1;
 #if defined (BANG_HISTORY)
   history_expansion_inhibited = 0;
 #endif

builtins/common.h

@@ -50,6 +50,7 @@ do { \
 #define SEVAL_NOLONGJMP 0x040
 #define SEVAL_FUNCDEF	0x080		/* only allow function definitions */
 #define SEVAL_ONECMD	0x100		/* only allow a single command */
+#define SEVAL_NOHISTEXP	0x200		/* inhibit history expansion */
 
 /* Flags for describe_command, shared between type.def and command.def */
 #define CDESC_ALL		0x001	/* type -a */

builtins/evalstring.c

@@ -168,8 +168,7 @@ parse_prologue (string, flags, tag)
   else
     unwind_protect_int (remember_on_history);	/* can be used in scripts */
 #  if defined (BANG_HISTORY)
-  if (interactive_shell)
-    unwind_protect_int (history_expansion_inhibited);
+  unwind_protect_int (history_expansion_inhibited);
 #  endif /* BANG_HISTORY */
 #endif /* HISTORY */
 
@@ -199,6 +198,10 @@ parse_prologue (string, flags, tag)
 #if defined (HISTORY)
   if (flags & SEVAL_NOHIST)
     bash_history_disable ();
+#  if defined (BANG_HISTORY)
+  if (flags & SEVAL_NOHISTEXP)
+    history_expansion_inhibited = 1;
+#  endif /* BANG_HISTORY */
 #endif /* HISTORY */
 }
 
@@ -211,6 +214,7 @@ parse_prologue (string, flags, tag)
    	(flags & SEVAL_NOHIST) -> call bash_history_disable ()
    	(flags & SEVAL_NOFREE) -> don't free STRING when finished
    	(flags & SEVAL_RESETLINE) -> reset line_number to 1
+   	(flags & SEVAL_NOHISTEXP) -> history_expansion_inhibited -> 1
 */
 
 int

examples/loadables/Makefile.in

@@ -102,7 +102,7 @@ INC = -I. -I.. -I$(topdir) -I$(topdir)/lib -I$(topdir)/builtins -I${srcdir} \
 
 ALLPROG = print truefalse sleep finfo logname basename dirname \
 	  tty pathchk tee head mkdir rmdir printenv id whoami \
-	  uname sync push ln unlink realpath strftime mypid
+	  uname sync push ln unlink realpath strftime mypid setpgid
 OTHERPROG = necho hello cat pushd
 
 all:	$(SHOBJ_STATUS)
@@ -202,6 +202,10 @@ strftime:	strftime.o
 mypid:	mypid.o
 	$(SHOBJ_LD) $(SHOBJ_LDFLAGS) $(SHOBJ_XLDFLAGS) -o $@ mypid.o $(SHOBJ_LIBS)
 
+
+setpgid:	setpgid.o
+	$(SHOBJ_LD) $(SHOBJ_LDFLAGS) $(SHOBJ_XLDFLAGS) -o $@ setpgid.o $(SHOBJ_LIBS)
+
 # pushd is a special case.  We use the same source that the builtin version
 # uses, with special compilation options.
 #
@@ -278,4 +282,4 @@ push.o: push.c
 mkdir.o: mkdir.c
 realpath.o: realpath.c
 strftime.o: strftime.c
-mypid.o: mypid.c
+setpgid.o: setpgid.c

examples/loadables/hello.c

@@ -94,4 +94,3 @@ struct builtin hello_struct = {
 	"hello",		/* usage synopsis; becomes short_doc */
 	0			/* reserved for internal use */
 };
-	

examples/loadables/setpgid.c

@@ -0,0 +1,121 @@
+/* setpgid.c: bash loadable wrapper for setpgid system call
+
+   An example of how to wrap a system call with a loadable builtin.
+
+   Originally contributed by Jason Vas Dias <jason.vas.dias@gmail.com>
+   
+   Bash 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.
+
+   Bash 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 Bash.  If not, see <http://www.gnu.org/licenses/>.
+*/
+
+#include <config.h>
+
+#if defined (HAVE_UNISTD_H)
+#  include <unistd.h>
+#endif
+#include <errno.h>
+#include <string.h>
+
+#include "bashtypes.h"
+#include "posixtime.h"
+
+#include <stdio.h>
+
+#include "builtins.h"
+#include "shell.h"
+#include "common.h"
+
+#include "bashgetopt.h"
+
+#if !defined (_POSIX_VERSION)
+#  define setpgid(pid, pgrp)      setpgrp (pid, pgrp)
+#endif
+
+int
+setpgid_builtin (list)
+      WORD_LIST *list;
+{
+  register WORD_LIST *wl;
+  intmax_t pid_arg, pgid_arg;
+  pid_t pid, pgid;
+  char *pidstr, *pgidstr;
+
+  wl = list;
+  pid = pgid = 0;
+
+  if (wl == 0 || wl->next == 0)
+    {
+      builtin_usage ();
+      return (EX_USAGE);
+    }
+
+  pidstr = wl->word ? wl->word->word : 0;
+  pgidstr = wl->next->word ? wl->next->word->word : 0;
+
+  if (pidstr == 0 || pgidstr == 0)
+    {
+      builtin_usage ();
+      return (EX_USAGE);
+    }
+      
+  if (legal_number (pidstr, &pid_arg) == 0)
+    {
+      builtin_error ("%s: pid argument must be numeric", pidstr);
+      return (EXECUTION_FAILURE);
+    }
+  if (pid_arg < 0)
+    {
+      builtin_error("%s: negative pid  values not allowed", pidstr);
+      return (EXECUTION_FAILURE);
+    }
+  pid = pid_arg;
+
+  if (legal_number (pgidstr, &pgid_arg) == 0)
+    {
+      builtin_error ("%s: pgrp argument must be numeric", pgidstr);
+      return (EXECUTION_FAILURE);
+    }
+  if (pgid_arg < 0)
+    {
+      builtin_error ("%s: negative pgrp values not allowed", pgidstr);
+      return (EXECUTION_FAILURE);
+    }
+  pgid = pgid_arg;
+
+  errno = 0;
+  if (setpgid(pid, pgid) < 0)
+    {
+      builtin_error("setpgid failed: %s", strerror (errno));
+      return (EXECUTION_FAILURE);     
+    }
+  return (EXECUTION_SUCCESS);     
+}
+
+const char *setpgid_doc[] = {
+	"invoke the setpgid(2) system call",
+	"",
+	"Arguments:",
+	"   pid : numeric process identifer, >= 0",
+	"   pgrpid: numeric process group identifier, >=0",
+	"See the setpgid(2) manual page.",
+	(const char *)NULL
+};
+
+struct builtin setpgid_struct = {
+	"setpgid",
+	setpgid_builtin,
+	BUILTIN_ENABLED,
+	(char **)setpgid_doc,
+	"setpgid pid pgrpid",
+	0
+};

lib/readline/display.c

@@ -1,6 +1,6 @@
 /* display.c -- readline redisplay facility. */
 
-/* Copyright (C) 1987-2013 Free Software Foundation, Inc.
+/* Copyright (C) 1987-2015 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.

lib/readline/histexpand.c

@@ -1,6 +1,6 @@
 /* histexpand.c -- history expansion. */
 
-/* Copyright (C) 1989-2012 Free Software Foundation, Inc.
+/* Copyright (C) 1989-2015 Free Software Foundation, Inc.
 
    This file contains the GNU History Library (History), a set of
    routines for managing the text of previously typed lines.

lib/readline/histfile.c

@@ -107,9 +107,19 @@ extern int errno;
 #  define PATH_MAX	1024	/* default */
 #endif
 
+extern void _hs_append_history_line PARAMS((int, const char *));
+
+/* history file version; currently unused */
+int history_file_version = 1;
+
 /* If non-zero, we write timestamps to the history file in history_do_write() */
 int history_write_timestamps = 0;
 
+/* If non-zero, we assume that a history file that starts with a timestamp
+   uses timestamp-delimited entries and can include multi-line history
+   entries. Used by read_history_range */
+int history_multiline_entries = 0;
+
 /* Immediately after a call to read_history() or read_history_range(), this
    will return the number of lines just read from the history file in that
    call. */
@@ -259,7 +269,7 @@ read_history_range (filename, from, to)
 {
   register char *line_start, *line_end, *p;
   char *input, *buffer, *bufend, *last_ts;
-  int file, current_line, chars_read;
+  int file, current_line, chars_read, has_timestamps, reset_comment_char;
   struct stat finfo;
   size_t file_size;
 #if defined (EFBIG)
@@ -336,6 +346,19 @@ read_history_range (filename, from, to)
   bufend = buffer + chars_read;
   current_line = 0;
 
+  /* Heuristic: the history comment character rarely changes, so assume we
+     have timestamps if the buffer starts with `#[:digit:]' and temporarily
+     set history_comment_char so timestamp parsing works right */
+  reset_comment_char = 0;
+  if (history_comment_char == '\0' && buffer[0] == '#' && isdigit ((unsigned char)buffer[1]))
+    {
+      history_comment_char = '#';
+      reset_comment_char = 1;
+    }
+
+  has_timestamps = HIST_TIMESTAMP_START (buffer);
+  history_multiline_entries += has_timestamps && history_write_timestamps;  
+
   /* Skip lines until we are at FROM. */
   for (line_start = line_end = buffer; line_end < bufend && current_line < from; line_end++)
     if (*line_end == '\n')
@@ -362,7 +385,10 @@ read_history_range (filename, from, to)
 	  {
 	    if (HIST_TIMESTAMP_START(line_start) == 0)
 	      {
-		add_history (line_start);
+	      	if (last_ts == NULL && history_multiline_entries)
+		  _hs_append_history_line (history_length - 1, line_start);
+		else
+		  add_history (line_start);
 		if (last_ts)
 		  {
 		    add_history_time (last_ts);
@@ -385,6 +411,8 @@ read_history_range (filename, from, to)
       }
 
   history_lines_read_from_file = current_line;
+  if (reset_comment_char)
+    history_comment_char = '\0';
 
   FREE (input);
 #ifndef HISTORY_USE_MMAP

lib/readline/history.c

@@ -1,6 +1,6 @@
 /* history.c -- standalone history library */
 
-/* Copyright (C) 1989-2011 Free Software Foundation, Inc.
+/* Copyright (C) 1989-2015 Free Software Foundation, Inc.
 
    This file contains the GNU History Library (History), a set of
    routines for managing the text of previously typed lines.
@@ -407,6 +407,30 @@ replace_history_entry (which, line, data)
   return (old_value);
 }
 
+/* Append LINE to the history line at offset WHICH, adding a newline to the
+   end of the current line first.  This can be used to construct multi-line
+   history entries while reading lines from the history file. */
+void
+_hs_append_history_line (which, line)
+     int which;
+     const char *line;
+{
+  HIST_ENTRY *hent;
+  size_t newlen, curlen;
+  char *newline;
+
+  hent = the_history[which];
+  curlen = strlen (hent->line);
+  newlen = curlen + strlen (line) + 2;
+  newline = realloc (hent->line, newlen);
+  if (newline)
+    {
+      hent->line = newline;
+      hent->line[curlen++] = '\n';
+      strcpy (hent->line + curlen, line);
+    }
+}
+
 /* Replace the DATA in the specified history entries, replacing OLD with
    NEW.  WHICH says which one(s) to replace:  WHICH == -1 means to replace
    all of the history entries where entry->data == OLD; WHICH == -2 means

lib/readline/history.h

@@ -1,6 +1,6 @@
 /* history.h -- the names of functions that you can call in history. */
 
-/* Copyright (C) 1989-2009 Free Software Foundation, Inc.
+/* Copyright (C) 1989-2015 Free Software Foundation, Inc.
 
    This file contains the GNU History Library (History), a set of
    routines for managing the text of previously typed lines.
@@ -263,6 +263,10 @@ extern int history_quotes_inhibit_expansion;
 
 extern int history_write_timestamps;
 
+/* These two are undocumented; the second is reserved for future use */
+extern int history_multiline_entries;
+extern int history_file_version;
+
 /* Backwards compatibility */
 extern int max_input_history;
 

lib/readline/isearch.c

@@ -6,7 +6,7 @@
 /*								    */
 /* **************************************************************** */
 
-/* Copyright (C) 1987-2012 Free Software Foundation, Inc.
+/* Copyright (C) 1987-2015 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.      

lib/readline/util.c

@@ -1,6 +1,6 @@
 /* util.c -- readline utility functions */
 
-/* Copyright (C) 1987-2012 Free Software Foundation, Inc.
+/* Copyright (C) 1987-2015 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.      

parse.y

@@ -2369,6 +2369,8 @@ shell_getc (remove_quoted_newline)
 	  if (current_delimiter (dstack) == '\'')
 	    history_expansion_inhibited = 1;
 #  endif
+	  /* Calling with a third argument of 1 allows remember_on_history to
+	     determine whether or not the line is saved to the history list */
 	  expansions = pre_process_line (shell_input_line, 1, 1);
 #  if defined (BANG_HISTORY)
 	  history_expansion_inhibited = old_hist;

shell.c

@@ -1695,6 +1695,9 @@ init_interactive ()
 {
   expand_aliases = interactive_shell = startup_state = 1;
   interactive = 1;
+#if defined (HISTORY)
+  remember_on_history = enable_history_list = 1;	/* XXX */
+#endif
 }
 
 static void
@@ -1718,6 +1721,9 @@ init_interactive_script ()
 {
   init_noninteractive ();
   expand_aliases = interactive_shell = startup_state = 1;
+#if defined (HISTORY)
+  remember_on_history = enable_history_list = 1;	/* XXX */
+#endif
 }
 
 void
@@ -1860,7 +1866,7 @@ shell_reinitialize ()
   /* XXX - should we set jobs_m_flag to 0 here? */
 
 #if defined (HISTORY)
-  bash_history_reinit (0);
+  bash_history_reinit (enable_history_list = 0);
 #endif /* HISTORY */
 
 #if defined (RESTRICTED_SHELL)

subst.c

@@ -1763,7 +1763,7 @@ skip_to_delim (string, start, delims, flags)
      int flags;
 {
   int i, pass_next, backq, dquote, si, c, oldjmp;
-  int invert, skipquote, skipcmd, noprocsub, completeflag, histexp;
+  int invert, skipquote, skipcmd, noprocsub, completeflag;
   int arithexp, skipcol;
   size_t slen;
   char *temp, open[3];
@@ -1776,7 +1776,6 @@ skip_to_delim (string, start, delims, flags)
   invert = (flags & SD_INVERT);
   skipcmd = (flags & SD_NOSKIPCMD) == 0;
   noprocsub = (flags & SD_NOPROCSUB);
-  histexp = (flags & SD_HISTEXP);
   completeflag = (flags & SD_COMPLETE) ? SX_COMPLETE : 0;
 
   arithexp = (flags & SD_ARITHEXP);
@@ -1835,11 +1834,6 @@ skip_to_delim (string, start, delims, flags)
       /* the usual case is to use skip_xxx_quoted, but we don't skip over double
 	 quoted strings when looking for the history expansion character as a
 	 delimiter. */
-      else if (histexp && dquote && c == '\'')
-        {
-          i++;
-          continue;
-        }
       /* special case for programmable completion which takes place before
          parser converts backslash-escaped single quotes between $'...' to
          `regular' single-quoted strings. */
@@ -1847,14 +1841,6 @@ skip_to_delim (string, start, delims, flags)
 	i = skip_single_quoted (string, slen, ++i, SX_COMPLETE);
       else if (c == '\'')
 	i = skip_single_quoted (string, slen, ++i, 0);
-      /* The posixly_correct test makes posix-mode shells allow double quotes
-	 to quote the history expansion character */
-      else if (histexp && posixly_correct == 0 && c == '"')
-	{
-	  dquote = 1 - dquote;
-	  i++;
-	  continue;
-	}     
       else if (c == '"')
 	i = skip_double_quoted (string, slen, ++i, completeflag);
       else if (c == LPAREN && arithexp)
@@ -1947,6 +1933,128 @@ skip_to_delim (string, start, delims, flags)
   CQ_RETURN(i);
 }
 
+#if defined (BANG_HISTORY)
+/* Skip to the history expansion character (delims[0]), paying attention to
+   quoted strings and command and process substitution.  This is a stripped-
+   down version of skip_to_delims.  The essential difference is that this
+   resets the quoting state when starting a command substitution */
+int
+skip_to_histexp (string, start, delims, flags)
+     char *string;
+     int start;
+     char *delims;
+     int flags;
+{
+  int i, pass_next, backq, dquote, si, c, oldjmp;
+  int histexp_comsub, histexp_backq, old_dquote;
+  size_t slen;
+  char *temp, open[3];
+  DECLARE_MBSTATE;
+
+  slen = strlen (string + start) + start;
+  oldjmp = no_longjmp_on_fatal_error;
+  if (flags & SD_NOJMP)
+    no_longjmp_on_fatal_error = 1;
+
+  histexp_comsub = histexp_backq = old_dquote = 0;
+
+  i = start;
+  pass_next = backq = dquote = 0;
+  while (c = string[i])
+    {
+      if (pass_next)
+	{
+	  pass_next = 0;
+	  if (c == 0)
+	    CQ_RETURN(i);
+	  ADVANCE_CHAR (string, slen, i);
+	  continue;
+	}
+      else if (c == '\\')
+	{
+	  pass_next = 1;
+	  i++;
+	  continue;
+	}
+      else if (backq && c == '`')
+	{
+	  backq = 0;
+	  histexp_backq--;
+	  dquote = old_dquote;
+	  i++;
+	  continue;
+	}
+      else if (c == '`')
+	{
+	  backq = 1;
+	  histexp_backq++;
+	  old_dquote = dquote;		/* simple - one level for now */
+	  dquote = 0;
+	  i++;
+	  continue;
+	}
+      /* When in double quotes, act as if the double quote is a member of
+	 history_no_expand_chars, like the history library does */
+      else if (dquote && c == delims[0] && string[i+1] == '"')
+	{
+	  i++;
+	  continue;
+	}
+      else if (c == delims[0])
+	break;
+      /* the usual case is to use skip_xxx_quoted, but we don't skip over double
+	 quoted strings when looking for the history expansion character as a
+	 delimiter. */
+      else if (dquote && c == '\'')
+        {
+          i++;
+          continue;
+        }
+      else if (c == '\'')
+	i = skip_single_quoted (string, slen, ++i, 0);
+      /* The posixly_correct test makes posix-mode shells allow double quotes
+	 to quote the history expansion character */
+      else if (posixly_correct == 0 && c == '"')
+	{
+	  dquote = 1 - dquote;
+	  i++;
+	  continue;
+	}     
+      else if (c == '"')
+	i = skip_double_quoted (string, slen, ++i, 0);
+#if defined (PROCESS_SUBSTITUTION)
+      else if ((c == '$' || c == '<' || c == '>') && string[i+1] == LPAREN && string[i+2] != LPAREN)
+#else
+      else if (c == '$' && string[i+1] == LPAREN && string[i+2] != LPAREN)
+#endif
+        {
+	  if (string[i+2] == '\0')
+	    CQ_RETURN(i+2);
+	  i += 2;
+	  histexp_comsub++;
+	  old_dquote = dquote;
+	  dquote = 0;
+        }
+      else if (histexp_comsub && c == RPAREN)
+	{
+	  histexp_comsub--;
+	  dquote = old_dquote;
+	  i++;
+	  continue;
+	}
+      else if (backq)		/* placeholder */
+	{
+	  ADVANCE_CHAR (string, slen, i);
+	  continue;
+	}
+      else
+	ADVANCE_CHAR (string, slen, i);
+    }
+
+  CQ_RETURN(i);
+}
+#endif /* BANG_HISTORY */
+
 #if defined (READLINE)
 /* Return 1 if the portion of STRING ending at EINDEX is quoted (there is
    an unclosed quoted string), or if the character at EINDEX is quoted
@@ -6488,18 +6596,28 @@ parameter_brace_expand_rhs (name, value, c, quoted, qdollaratp, hasdollarat)
     free (temp);
   if (l)
     {
+      /* If l->next is not null, we know that TEMP contained "$@", since that
+	 is the only expansion that creates more than one word. */
+      if (qdollaratp && ((hasdol && quoted) || l->next))
+	*qdollaratp = 1;
+
       /* The expansion of TEMP returned something.  We need to treat things
 	  slightly differently if HASDOL is non-zero.  If we have "$@", the
 	  individual words have already been quoted.  We need to turn them
 	  into a string with the words separated by the first character of
 	  $IFS without any additional quoting, so string_list_dollar_at won't
-	  do the right thing.  We use string_list_dollar_star instead. */
-      temp = (hasdol || l->next) ? string_list_dollar_star (l) : string_list (l);
+	  do the right thing.  If IFS is null, we want "$@" to split into
+	  separate arguments, not be concatenated, so we use string_list_internal
+	  and mark the word to be split on spaces later.  We use
+	  string_list_dollar_star for "$@" otherwise. */
+      if (l->next && ifs_is_null)
+	{
+	  temp = string_list_internal (l, " ");
+	  w->flags |= W_SPLITSPACE;
+	}
+      else
+	temp = (hasdol || l->next) ? string_list_dollar_star (l) : string_list (l);
 
-      /* If l->next is not null, we know that TEMP contained "$@", since that
-	 is the only expansion that creates more than one word. */
-      if (qdollaratp && ((hasdol && quoted) || l->next))
-	*qdollaratp = 1;
       /* If we have a quoted null result (QUOTED_NULL(temp)) and the word is
 	 a quoted null (l->next == 0 && QUOTED_NULL(l->word->word)), the
 	 flags indicate it (l->word->flags & W_HASQUOTEDNULL), and the
@@ -9477,7 +9595,9 @@ finished_with_string:
 	 with the first character of $IFS, so we split on $IFS.  If
 	 SPLIT_ON_SPACES is set, we expanded $* (unquoted) with IFS either
 	 unset or null, and we want to make sure that we split on spaces
-	 regardless of what else has happened to IFS since the expansion. */
+	 regardless of what else has happened to IFS since the expansion,
+	 or we expanded "$@" with IFS null and we need to split the positional
+	 parameters into separate words. */
       if (split_on_spaces)
 	list = list_string (istring, " ", 1);	/* XXX quoted == 1? */
       /* If we have $@ (has_dollar_at != 0) and we are in a context where we

subst.h

@@ -1,6 +1,6 @@
 /* subst.h -- Names of externally visible functions in subst.c. */
 
-/* Copyright (C) 1993-2010 Free Software Foundation, Inc.
+/* Copyright (C) 1993-2015 Free Software Foundation, Inc.
 
    This file is part of GNU Bash, the Bourne Again SHell.
 
@@ -297,6 +297,10 @@ extern char *cond_expand_word __P((WORD_DESC *, int));
 
 extern int skip_to_delim __P((char *, int, char *, int));
 
+#if defined (BANG_HISTORY)
+extern int skip_to_histexp __P((char *, int, char *, int));
+#endif
+
 #if defined (READLINE)
 extern int char_is_quoted __P((char *, int));
 extern int unclosed_pair __P((char *, int, char *));

tests/dollar-at-star

@@ -218,6 +218,7 @@ ${THIS_SH} ./dollar-at-star3.sub
 ${THIS_SH} ./dollar-at-star4.sub
 ${THIS_SH} ./dollar-at-star5.sub
 ${THIS_SH} ./dollar-at-star6.sub
+${THIS_SH} ./dollar-at-star7.sub
 
 # tests for special expansion of "$*" and "${array[*]}" when used with other
 # expansions -- bugs through bash-2.05b

tests/dollar-at-star7.sub

@@ -0,0 +1,25 @@
+IFS=''			# testing with only empty IFS
+
+set -- this is a test
+
+printf '|%s|\n' ${1+"$@"}
+echo
+printf '|%s|\n' "${1+$@}"
+echo
+printf '|%s|\n' "$@"
+echo
+
+printf '|%s|\n' ${1-"$@"}
+printf '|%s|\n' "${1-$@}"
+
+echo
+: ${foo:="$@"}
+printf '|%s|\n' "$foo"
+
+unset foo
+: "${foo:=$@}"
+printf '|%s|\n' "$foo"
+
+unset foo
+printf '|%s|\n' ${foo-"$@"}
+printf '|%s|\n' "${foo-$@}"

tests/dollar.right

@@ -266,6 +266,34 @@ argv[3] = <'c'>
 argv[1] = <'a'>
 argv[2] = <'b'>
 argv[3] = <'c'>
+|this|
+|is|
+|a|
+|test|
+
+|this|
+|is|
+|a|
+|test|
+
+|this|
+|is|
+|a|
+|test|
+
+|this|
+|this|
+
+|this is a test|
+|this is a test|
+|this|
+|is|
+|a|
+|test|
+|this|
+|is|
+|a|
+|test|
 xa|xb|xc
 xa|xb|xc
 a|b|c

tests/histexp.right

@@ -150,3 +150,42 @@ echo "#!/bin/bash" set -o posix
 #!/bin/bash set -o posix
 !!
 !!
+a
+echo $(echo echo a)
+echo a
+a
+echo echo a $(echo echo a)
+echo a echo a
+b
+!! $(echo !!)
+c
+echo "echo c" "$(echo echo c)"
+echo c echo c
+d
+echo "echo d" $(echo "echo d")
+echo d echo d
+e
+!! !!
+f
+!!
+f
+!!
+g
+echo "echo g"
+echo g
+g
+eval echo "echo g"
+echo g
+a
+cat < <(echo echo a)
+echo a
+b
+echo echo b `echo echo b`
+echo b echo b
+c
+!
+d
+!
+e
+! !
+./histexp4.sub: line 20: !': event not found

tests/histexp.tests

@@ -130,3 +130,5 @@ echo !shopt*
 
 ${THIS_SH} ./histexp1.sub
 ${THIS_SH} ./histexp2.sub
+${THIS_SH} ./histexp3.sub
+${THIS_SH} ./histexp4.sub

tests/histexp3.sub

@@ -0,0 +1,35 @@
+HISTFILE=${TMPDIR}/bashhist-$$
+
+set -o history
+set -o histexpand
+
+echo a
+echo $(echo !!)
+
+echo a
+echo !! $(echo !!)
+
+echo b
+echo '!!' '$(echo !!)'
+
+echo c
+echo "!!" "$(echo !!)"
+
+echo d
+echo "!!" $(echo "!!")
+
+echo e
+echo '!!' $(echo '!!')
+
+echo f
+echo '!!'
+echo f
+eval echo '!!'
+
+echo g
+echo "!!"
+echo g
+eval echo "!!"
+
+set +o history
+rm -f $HISTFILE		# just in case

tests/histexp4.sub

@@ -0,0 +1,23 @@
+HISTFILE=$TMPDIR/bashhist-$$
+
+set -o history
+set -o histexpand
+
+echo a
+cat < <(echo !!)
+
+echo b
+echo !! `echo !!`
+
+echo c
+echo "$(echo "!" )"
+
+echo d
+echo "$(echo '!' )"
+
+echo e
+echo '!' "!"
+echo "'!'"
+
+set +o history
+rm -f $HISTFILE

variables.c

@@ -503,7 +503,11 @@ initialize_shell_variables (env, privmode)
 #endif
       set_if_not ("PS2", secondary_prompt);
     }
-  set_if_not ("PS4", "+ ");
+
+  if (current_user.euid == 0)
+    bind_variable ("PS4", "+", 0);
+  else
+    set_if_not ("PS4", "+ ");
 
   /* Don't allow IFS to be imported from the environment. */
   temp_var = bind_variable ("IFS", " \t\n", 0);