Bash-4.2 direxpand shopt variable and associated changes, including heuristics to avoid quoting shell variables during word completion

bashline.c

@@ -121,6 +121,9 @@ static int bash_directory_completion_hook __P((char **));
 static int filename_completion_ignore __P((char **));
 static int bash_push_line __P((void));
 
+static rl_icppfunc_t *save_directory_hook __P((void));
+static void reset_directory_hook __P((rl_icppfunc_t *));
+
 static void cleanup_expansion_error __P((void));
 static void maybe_make_readline_line __P((char *));
 static void set_up_new_line __P((char *));
@@ -243,10 +246,16 @@ int force_fignore = 1;
 /* Perform spelling correction on directory names during word completion */
 int dircomplete_spelling = 0;
 
+/* Expand directory names during word/filename completion. */
+int dircomplete_expand = 0;
+
 static char *bash_completer_word_break_characters = " \t\n\"'@><=;|&(:";
 static char *bash_nohostname_word_break_characters = " \t\n\"'><=;|&(:";
 /* )) */
 
+static const char *default_filename_quote_characters = " \t\n\\\"'@<>=;|&()#$`?*[!:{~";	/*}*/
+static char *custom_filename_quote_characters = 0;
+
 static rl_hook_func_t *old_rl_startup_hook = (rl_hook_func_t *)NULL;
 
 static int dot_in_path = 0;
@@ -501,7 +510,7 @@ initialize_readline ()
 
   /* Tell the completer that we might want to follow symbolic links or
      do other expansion on directory names. */
-  rl_directory_rewrite_hook = bash_directory_completion_hook;
+  set_directory_hook ();
 
   rl_filename_rewrite_hook = bash_filename_rewrite_hook;
 
@@ -529,7 +538,7 @@ initialize_readline ()
   enable_hostname_completion (perform_hostname_completion);
 
   /* characters that need to be quoted when appearing in filenames. */
-  rl_filename_quote_characters = " \t\n\\\"'@<>=;|&()#$`?*[!:{~";	/*}*/
+  rl_filename_quote_characters = default_filename_quote_characters;
 
   rl_filename_quoting_function = bash_quote_filename;
   rl_filename_dequoting_function = bash_dequote_filename;
@@ -564,8 +573,10 @@ bashline_reset ()
   tilde_initialize ();
   rl_attempted_completion_function = attempt_shell_completion;
   rl_completion_entry_function = NULL;
-  rl_directory_rewrite_hook = bash_directory_completion_hook;
   rl_ignore_some_completions_function = filename_completion_ignore;
+  rl_filename_quote_characters = default_filename_quote_characters;
+
+  set_directory_hook ();
 }
 
 /* Contains the line to push into readline. */
@@ -1279,6 +1290,9 @@ attempt_shell_completion (text, start, end)
   matches = (char **)NULL;
   rl_ignore_some_completions_function = filename_completion_ignore;
 
+  rl_filename_quote_characters = default_filename_quote_characters;
+  set_directory_hook ();
+
   /* Determine if this could be a command word.  It is if it appears at
      the start of the line (ignoring preceding whitespace), or if it
      appears after a character that separates commands.  It cannot be a
@@ -1591,6 +1605,12 @@ command_word_completion_function (hint_text, state)
 	    }
 	  else
 	    {
+	     if (dircomplete_expand && dot_or_dotdot (filename_hint))
+		{
+		  dircomplete_expand = 0;
+		  set_directory_hook ();
+		  dircomplete_expand = 1;
+		}
 	      mapping_over = 4;
 	      goto inner;
 	    }
@@ -1791,6 +1811,9 @@ globword:
 
  inner:
   val = rl_filename_completion_function (filename_hint, istate);
+  if (mapping_over == 4 && dircomplete_expand)
+    set_directory_hook ();
+
   istate = 1;
 
   if (val == 0)
@@ -2693,6 +2716,52 @@ bash_filename_rewrite_hook (fname, fnlen)
   return conv;
 }
 
+/* Functions to save and restore the appropriate directory hook */
+/* This is not static so the shopt code can call it */
+void
+set_directory_hook ()
+{
+  if (dircomplete_expand)
+    {
+      rl_directory_completion_hook = bash_directory_completion_hook;
+      rl_directory_rewrite_hook = (rl_icppfunc_t *)0;
+    }
+  else
+    {
+      rl_directory_rewrite_hook = bash_directory_completion_hook;
+      rl_directory_completion_hook = (rl_icppfunc_t *)0;
+    }
+}
+
+static rl_icppfunc_t *
+save_directory_hook ()
+{
+  rl_icppfunc_t *ret;
+
+  if (dircomplete_expand)
+    {
+      ret = rl_directory_completion_hook;
+      rl_directory_completion_hook = (rl_icppfunc_t *)NULL;
+    }
+  else
+    {
+      ret = rl_directory_rewrite_hook;
+      rl_directory_rewrite_hook = (rl_icppfunc_t *)NULL;
+    }
+
+  return ret;
+}
+
+static void
+restore_directory_hook (hookf)
+     rl_icppfunc_t *hookf;
+{
+  if (dircomplete_expand)
+    rl_directory_completion_hook = hookf;
+  else
+    rl_directory_rewrite_hook = hookf;
+}
+
 /* Handle symbolic link references and other directory name
    expansions while hacking completion.  This should return 1 if it modifies
    the DIRNAME argument, 0 otherwise.  It should make sure not to modify
@@ -2702,20 +2771,31 @@ bash_directory_completion_hook (dirname)
      char **dirname;
 {
   char *local_dirname, *new_dirname, *t;
-  int return_value, should_expand_dirname;
+  int return_value, should_expand_dirname, nextch, closer;
   WORD_LIST *wl;
   struct stat sb;
 
-  return_value = should_expand_dirname = 0;
+  return_value = should_expand_dirname = nextch = closer = 0;
   local_dirname = *dirname;
 
-  if (mbschr (local_dirname, '$'))
-    should_expand_dirname = 1;
+  if (t = mbschr (local_dirname, '$'))
+    {
+      should_expand_dirname = '$';
+      nextch = t[1];
+      /* Deliberately does not handle the deprecated $[...] arithmetic
+	 expansion syntax */
+      if (nextch == '(')
+	closer = ')';
+      else if (nextch == '{')
+	closer = '}';
+      else
+	nextch = 0;
+    }
   else
     {
       t = mbschr (local_dirname, '`');
       if (t && unclosed_pair (local_dirname, strlen (local_dirname), "`") == 0)
-	should_expand_dirname = 1;
+	should_expand_dirname = '`';
     }
 
 #if defined (HAVE_LSTAT)
@@ -2739,6 +2819,23 @@ bash_directory_completion_hook (dirname)
 	  free (new_dirname);
 	  dispose_words (wl);
 	  local_dirname = *dirname;
+	  /* XXX - change rl_filename_quote_characters here based on
+	     should_expand_dirname/nextch/closer.  This is the only place
+	     custom_filename_quote_characters is modified. */
+	  if (rl_filename_quote_characters && *rl_filename_quote_characters)
+	    {
+	      int i, j, c;
+	      i = strlen (default_filename_quote_characters);
+	      custom_filename_quote_characters = xrealloc (custom_filename_quote_characters, i+1);
+	      for (i = j = 0; c = default_filename_quote_characters[i]; i++)
+		{
+		  if (c == should_expand_dirname || c == nextch || c == closer)
+		    continue;
+		  custom_filename_quote_characters[j++] = c;
+		}
+	      custom_filename_quote_characters[j] = '\0';
+	      rl_filename_quote_characters = custom_filename_quote_characters;
+	    }
 	}
       else
 	{
@@ -3002,12 +3099,13 @@ bash_complete_filename_internal (what_to_do)
 
   orig_func = rl_completion_entry_function;
   orig_attempt_func = rl_attempted_completion_function;
-  orig_dir_func = rl_directory_rewrite_hook;
   orig_ignore_func = rl_ignore_some_completions_function;
   orig_rl_completer_word_break_characters = rl_completer_word_break_characters;
+
+  orig_dir_func = save_directory_hook ();
+
   rl_completion_entry_function = rl_filename_completion_function;
   rl_attempted_completion_function = (rl_completion_func_t *)NULL;
-  rl_directory_rewrite_hook = (rl_icppfunc_t *)NULL;
   rl_ignore_some_completions_function = filename_completion_ignore;
   rl_completer_word_break_characters = " \t\n\"\'";
 
@@ -3015,10 +3113,11 @@ bash_complete_filename_internal (what_to_do)
 
   rl_completion_entry_function = orig_func;
   rl_attempted_completion_function = orig_attempt_func;
-  rl_directory_rewrite_hook = orig_dir_func;
   rl_ignore_some_completions_function = orig_ignore_func;
   rl_completer_word_break_characters = orig_rl_completer_word_break_characters;
 
+  restore_directory_hook (orig_dir_func);
+
   return r;
 }
 

bashline.h

@@ -33,10 +33,15 @@ extern void bashline_reset __P((void));
 extern void bashline_reinitialize __P((void));
 extern int bash_re_edit __P((char *));
 
+extern void bashline_set_event_hook __P((void));
+extern void bashline_reset_event_hook __P((void));
+
 extern int bind_keyseq_to_unix_command __P((char *));
 
 extern char **bash_default_completion __P((const char *, int, int, int, int));
 
+void set_directory_hook __P((void));
+
 /* Used by programmable completion code. */
 extern char *command_word_completion_function __P((const char *, int));
 extern char *bash_groupname_completion_function __P((const char *, int));

builtins/shopt.def

@@ -61,6 +61,10 @@ $END
 #include "common.h"
 #include "bashgetopt.h"
 
+#if defined (READLINE)
+#  include "../bashline.h"
+#endif
+
 #if defined (HISTORY)
 #  include "../bashhist.h"
 #endif
@@ -94,7 +98,7 @@ extern int extended_glob;
 extern int hist_verify, history_reediting, perform_hostname_completion;
 extern int no_empty_command_completion;
 extern int force_fignore;
-extern int dircomplete_spelling;
+extern int dircomplete_spelling, dircomplete_expand;
 
 extern int enable_hostname_completion __P((int));
 #endif
@@ -121,6 +125,10 @@ static int set_compatibility_level __P((char *, int));
 static int set_restricted_shell __P((char *, int));
 #endif
 
+#if defined (READLINE)
+static int shopt_set_complete_direxpand __P((char *, int));
+#endif
+
 static int shopt_login_shell;
 static int shopt_compat31;
 static int shopt_compat32;
@@ -150,6 +158,7 @@ static struct {
   { "compat40", &shopt_compat40, set_compatibility_level },
   { "compat41", &shopt_compat41, set_compatibility_level },
 #if defined (READLINE)
+  { "direxpand", &dircomplete_expand, shopt_set_complete_direxpand },
   { "dirspell", &dircomplete_spelling, (shopt_set_func_t *)NULL },
 #endif
   { "dotglob", &glob_dot_filenames, (shopt_set_func_t *)NULL },
@@ -535,6 +544,17 @@ set_compatibility_level (option_name, mode)
   return 0;
 }
 
+#if defined (READLINE)
+static int
+shopt_set_complete_direxpand (option_name, mode)
+     char *option_name;
+     int mode;
+{
+  set_directory_hook ();
+  return 0;
+}
+#endif
+
 #if defined (RESTRICTED_SHELL)
 /* Don't allow the value of restricted_shell to be modified. */
 

doc/bash.1

@@ -8948,6 +8948,16 @@ parameter expansion as a special character.  The single quotes must match
 quoted.  This is the behavior of posix mode through version 4.1.
 The default bash behavior remains as in previous versions.
 .TP 8
+.B direxpand
+If set,
+.B bash
+replaces directory names with the results of word expansion when performing
+filename completion.  This changes the contents of the readline editing
+buffer.
+If not set,
+.B bash
+attempts to preserve what the user typed.
+.TP 8
 .B dirspell
 If set,
 .B bash

doc/bashref.texi

@@ -4535,6 +4535,13 @@ parameter expansion as a special character.  The single quotes must match
 quoted.  This is the behavior of @sc{posix} mode through version 4.1.
 The default Bash behavior remains as in previous versions.
 
+@item direxpand
+If set, Bash
+replaces directory names with the results of word expansion when performing
+filename completion.  This changes the contents of the readline editing
+buffer.
+If not set, Bash attempts to preserve what the user typed.
+
 @item dirspell
 If set, Bash
 attempts spelling correction on directory names during word completion 

tests/shopt.right

@@ -12,6 +12,7 @@ shopt -u compat31
 shopt -u compat32
 shopt -u compat40
 shopt -u compat41
+shopt -u direxpand
 shopt -u dirspell
 shopt -u dotglob
 shopt -u execfail
@@ -68,6 +69,7 @@ shopt -u compat31
 shopt -u compat32
 shopt -u compat40
 shopt -u compat41
+shopt -u direxpand
 shopt -u dirspell
 shopt -u dotglob
 shopt -u execfail
@@ -101,6 +103,7 @@ compat31       	off
 compat32       	off
 compat40       	off
 compat41       	off
+direxpand      	off
 dirspell       	off
 dotglob        	off
 execfail       	off