Bash-4.0 patchlevel 38

1 files changed, 137 insertions, 14 deletions

diff --git a/subst.c b/subst.c
index 62a3d02..78f217c 100644
--- a/subst.c
+++ b/subst.c
@@ -85,6 +85,7 @@ extern int errno;
 
 /* Flags for the `pflags' argument to param_expand() */
 #define PF_NOCOMSUB	0x01	/* Do not perform command substitution */
+#define PF_IGNUNBOUND	0x02	/* ignore unbound vars even if -u set */
 
 /* These defs make it easier to use the editor. */
 #define LBRACE		'{'
@@ -222,6 +223,7 @@ static inline int skip_single_quoted __P((const char *, size_t, int));
 static int skip_double_quoted __P((char *, size_t, int));
 static char *extract_delimited_string __P((char *, int *, char *, char *, char *, int));
 static char *extract_dollar_brace_string __P((char *, int *, int, int));
+static int skip_matched_pair __P((const char *, int, int, int, int));
 
 static char *pos_params __P((char *, int, int, int));
 
@@ -262,7 +264,7 @@ static int valid_brace_expansion_word __P((char *, int));
 static int chk_atstar __P((char *, int, int *, int *));
 static int chk_arithsub __P((const char *, int));
 
-static WORD_DESC *parameter_brace_expand_word __P((char *, int, int));
+static WORD_DESC *parameter_brace_expand_word __P((char *, int, int, int));
 static WORD_DESC *parameter_brace_expand_indir __P((char *, int, int, int *, int *));
 static WORD_DESC *parameter_brace_expand_rhs __P((char *, char *, int, int, int *, int *));
 static void parameter_brace_expand_error __P((char *, char *));
@@ -1374,6 +1376,107 @@ unquote_bang (string)
 
 #define CQ_RETURN(x) do { no_longjmp_on_fatal_error = 0; return (x); } while (0)
 
+/* This function assumes s[i] == open; returns with s[ret] == close; used to
+   parse array subscripts.  FLAGS currently unused. */
+static int
+skip_matched_pair (string, start, open, close, flags)
+     const char *string;
+     int start, open, close, flags;
+{
+  int i, pass_next, backq, si, c, count;
+  size_t slen;
+  char *temp, *ss;
+  DECLARE_MBSTATE;
+
+  slen = strlen (string + start) + start;
+  no_longjmp_on_fatal_error = 1;
+
+  i = start + 1;		/* skip over leading bracket */
+  count = 1;
+  pass_next = backq = 0;
+  ss = (char *)string;
+  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)
+	{
+	  if (c == '`')
+	    backq = 0;
+	  ADVANCE_CHAR (string, slen, i);
+	  continue;
+	}
+      else if (c == '`')
+	{
+	  backq = 1;
+	  i++;
+	  continue;
+	}
+      else if (c == open)
+	{
+	  count++;
+	  i++;
+	  continue;
+	}
+      else if (c == close)
+	{
+	  count--;
+	  if (count == 0)
+	    break;
+	  i++;
+	  continue;
+	}
+      else if (c == '\'' || c == '"')
+	{
+	  i = (c == '\'') ? skip_single_quoted (ss, slen, ++i)
+			  : skip_double_quoted (ss, slen, ++i);
+	  /* no increment, the skip functions increment past the closing quote. */
+	}
+      else if (c == '$' && (string[i+1] == LPAREN || string[i+1] == LBRACE))
+	{
+	  si = i + 2;
+	  if (string[si] == '\0')
+	    CQ_RETURN(si);
+
+	  if (string[i+1] == LPAREN)
+	    temp = extract_delimited_string (ss, &si, "$(", "(", ")", SX_NOALLOC|SX_COMMAND); /* ) */
+	  else
+	    temp = extract_dollar_brace_string (ss, &si, 0, SX_NOALLOC);
+	  i = si;
+	  if (string[i] == '\0')	/* don't increment i past EOS in loop */
+	    break;
+	  i++;
+	  continue;
+	}
+      else
+	ADVANCE_CHAR (string, slen, i);
+    }
+
+  CQ_RETURN(i);
+}
+
+#if defined (ARRAY_VARS)
+int
+skipsubscript (string, start)
+     const char *string;
+     int start;
+{
+  return (skip_matched_pair (string, start, '[', ']', 0));
+}
+#endif
+
 /* Skip characters in STRING until we find a character in DELIMS, and return
    the index of that character.  START is the index into string at which we
    begin.  This is similar in spirit to strpbrk, but it returns an index into
@@ -5093,9 +5196,9 @@ chk_atstar (name, quoted, quoted_dollar_atp, contains_dollar_at)
    the shell, e.g., "@", "$", "*", etc.  QUOTED, if non-zero, means that
    NAME was found inside of a double-quoted expression. */
 static WORD_DESC *
-parameter_brace_expand_word (name, var_is_special, quoted)
+parameter_brace_expand_word (name, var_is_special, quoted, pflags)
      char *name;
-     int var_is_special, quoted;
+     int var_is_special, quoted, pflags;
 {
   WORD_DESC *ret;
   char *temp, *tt;
@@ -5127,7 +5230,7 @@ parameter_brace_expand_word (name, var_is_special, quoted)
       strcpy (tt + 1, name);
 
       ret = param_expand (tt, &sindex, quoted, (int *)NULL, (int *)NULL,
-			  (int *)NULL, (int *)NULL, 0);
+			  (int *)NULL, (int *)NULL, pflags);
       free (tt);
     }
 #if defined (ARRAY_VARS)
@@ -5188,7 +5291,7 @@ parameter_brace_expand_indir (name, var_is_special, quoted, quoted_dollar_atp, c
   char *temp, *t;
   WORD_DESC *w;
 
-  w = parameter_brace_expand_word (name, var_is_special, quoted);
+  w = parameter_brace_expand_word (name, var_is_special, quoted, PF_IGNUNBOUND);
   t = w->word;
   /* Have to dequote here if necessary */
   if (t)
@@ -5205,7 +5308,7 @@ parameter_brace_expand_indir (name, var_is_special, quoted, quoted_dollar_atp, c
   if (t == 0)
     return (WORD_DESC *)NULL;
 
-  w = parameter_brace_expand_word (t, SPECIAL_VAR(t, 0), quoted);
+  w = parameter_brace_expand_word (t, SPECIAL_VAR(t, 0), quoted, 0);
   free (t);
 
   return w;
@@ -6503,7 +6606,7 @@ parameter_brace_expand (string, indexp, quoted, quoted_dollar_atp, contains_doll
 	    *contains_dollar_at = 1;
 	}
       free (x);
-      free (xlist);
+      dispose_words (xlist);
       free (temp1);
       *indexp = sindex;
 
@@ -6556,7 +6659,7 @@ parameter_brace_expand (string, indexp, quoted, quoted_dollar_atp, contains_doll
   if (want_indir)
     tdesc = parameter_brace_expand_indir (name + 1, var_is_special, quoted, quoted_dollar_atp, contains_dollar_at);
   else
-    tdesc = parameter_brace_expand_word (name, var_is_special, quoted);
+    tdesc = parameter_brace_expand_word (name, var_is_special, quoted, PF_IGNUNBOUND);
 
   if (tdesc)
     {
@@ -6664,13 +6767,13 @@ parameter_brace_expand (string, indexp, quoted, quoted_dollar_atp, contains_doll
       return &expand_wdesc_error;
 
     case RBRACE:
-      if (var_is_set == 0 && unbound_vars_is_error)
+      if (var_is_set == 0 && unbound_vars_is_error && ((name[0] != '@' && name[0] != '*') || name[1]))
 	{
+	  last_command_exit_value = EXECUTION_FAILURE;
 	  err_unboundvar (name);
 	  FREE (value);
 	  FREE (temp);
 	  free (name);
-	  last_command_exit_value = EXECUTION_FAILURE;
 	  return (interactive_shell ? &expand_wdesc_error : &expand_wdesc_fatal);
 	}
       break;
@@ -6887,15 +6990,25 @@ param_expand (string, sindex, quoted, expanded_something,
     case '*':		/* `$*' */
       list = list_rest_of_args ();
 
-      if (list == 0 && unbound_vars_is_error)
+#if 0
+      /* According to austin-group posix proposal by Geoff Clare in
+	 <20090505091501.GA10097@squonk.masqnet> of 5 May 2009:
+
+ 	"The shell shall write a message to standard error and
+ 	 immediately exit when it tries to expand an unset parameter
+ 	 other than the '@' and '*' special parameters."
+      */
+
+      if (list == 0 && unbound_vars_is_error && (pflags & PF_IGNUNBOUND) == 0)
 	{
 	  uerror[0] = '$';
 	  uerror[1] = '*';
 	  uerror[2] = '\0';
-	  err_unboundvar (uerror);
 	  last_command_exit_value = EXECUTION_FAILURE;
+	  err_unboundvar (uerror);
 	  return (interactive_shell ? &expand_wdesc_error : &expand_wdesc_fatal);
 	}
+#endif
 
       /* If there are no command-line arguments, this should just
 	 disappear if there are other characters in the expansion,
@@ -6949,15 +7062,25 @@ param_expand (string, sindex, quoted, expanded_something,
     case '@':		/* `$@' */
       list = list_rest_of_args ();
 
-      if (list == 0 && unbound_vars_is_error)
+#if 0
+      /* According to austin-group posix proposal by Geoff Clare in
+	 <20090505091501.GA10097@squonk.masqnet> of 5 May 2009:
+
+ 	"The shell shall write a message to standard error and
+ 	 immediately exit when it tries to expand an unset parameter
+ 	 other than the '@' and '*' special parameters."
+      */
+
+      if (list == 0 && unbound_vars_is_error && (pflags & PF_IGNUNBOUND) == 0)
 	{
 	  uerror[0] = '$';
 	  uerror[1] = '@';
 	  uerror[2] = '\0';
-	  err_unboundvar (uerror);
 	  last_command_exit_value = EXECUTION_FAILURE;
+	  err_unboundvar (uerror);
 	  return (interactive_shell ? &expand_wdesc_error : &expand_wdesc_fatal);
 	}
+#endif
 
       /* We want to flag the fact that we saw this.  We can't turn
 	 off quoting entirely, because other characters in the