1 /* arrayfunc.c -- High-level array functions used by other parts of the shell. */
3 /* Copyright (C) 2001-2010 Free Software Foundation, Inc.
5 This file is part of GNU Bash, the Bourne Again SHell.
7 Bash is free software: you can redistribute it and/or modify
8 it under the terms of the GNU General Public License as published by
9 the Free Software Foundation, either version 3 of the License, or
10 (at your option) any later version.
12 Bash is distributed in the hope that it will be useful,
13 but WITHOUT ANY WARRANTY; without even the implied warranty of
14 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
15 GNU General Public License for more details.
17 You should have received a copy of the GNU General Public License
18 along with Bash. If not, see <http://www.gnu.org/licenses/>.
23 #if defined (ARRAY_VARS)
25 #if defined (HAVE_UNISTD_H)
37 #include "builtins/common.h"
39 extern char *this_command_name;
40 extern int last_command_exit_value;
41 extern int array_needs_making;
43 static SHELL_VAR *bind_array_var_internal __P((SHELL_VAR *, arrayind_t, char *, char *, int));
45 static char *quote_assign __P((const char *));
46 static void quote_array_assignment_chars __P((WORD_LIST *));
47 static char *array_value_internal __P((char *, int, int, int *, arrayind_t *));
49 /* Standard error message to use when encountering an invalid array subscript */
50 const char * const bash_badsub_errmsg = N_("bad array subscript");
52 /* **************************************************************** */
54 /* Functions to manipulate array variables and perform assignments */
56 /* **************************************************************** */
58 /* Convert a shell variable to an array variable. The original value is
61 convert_var_to_array (var)
67 oldval = value_cell (var);
68 array = array_create ();
70 array_insert (array, 0, oldval);
72 FREE (value_cell (var));
73 var_setarray (var, array);
75 /* these aren't valid anymore */
76 var->dynamic_value = (sh_var_value_func_t *)NULL;
77 var->assign_func = (sh_var_assign_func_t *)NULL;
79 INVALIDATE_EXPORTSTR (var);
83 VSETATTR (var, att_array);
84 VUNSETATTR (var, att_invisible);
89 /* Convert a shell variable to an array variable. The original value is
92 convert_var_to_assoc (var)
98 oldval = value_cell (var);
99 hash = assoc_create (0);
101 assoc_insert (hash, savestring ("0"), oldval);
103 FREE (value_cell (var));
104 var_setassoc (var, hash);
106 /* these aren't valid anymore */
107 var->dynamic_value = (sh_var_value_func_t *)NULL;
108 var->assign_func = (sh_var_assign_func_t *)NULL;
110 INVALIDATE_EXPORTSTR (var);
111 if (exported_p (var))
112 array_needs_making++;
114 VSETATTR (var, att_assoc);
115 VUNSETATTR (var, att_invisible);
121 bind_array_var_internal (entry, ind, key, value, flags)
131 /* If we're appending, we need the old value of the array reference, so
132 fake out make_variable_value with a dummy SHELL_VAR */
133 if (flags & ASS_APPEND)
135 dentry = (SHELL_VAR *)xmalloc (sizeof (SHELL_VAR));
136 dentry->name = savestring (entry->name);
138 newval = assoc_reference (assoc_cell (entry), key);
140 newval = array_reference (array_cell (entry), ind);
142 dentry->value = savestring (newval);
145 dentry->value = (char *)xmalloc (1);
146 dentry->value[0] = '\0';
148 dentry->exportstr = 0;
149 dentry->attributes = entry->attributes & ~(att_array|att_assoc|att_exported);
150 /* Leave the rest of the members uninitialized; the code doesn't look
152 newval = make_variable_value (dentry, value, flags);
153 dispose_variable (dentry);
156 newval = make_variable_value (entry, value, flags);
158 if (entry->assign_func)
159 (*entry->assign_func) (entry, newval, ind, key);
160 else if (assoc_p (entry))
161 assoc_insert (assoc_cell (entry), key, newval);
163 array_insert (array_cell (entry), ind, newval);
169 /* Perform an array assignment name[ind]=value. If NAME already exists and
170 is not an array, and IND is 0, perform name=value instead. If NAME exists
171 and is not an array, and IND is not 0, convert it into an array with the
172 existing value as name[0].
174 If NAME does not exist, just create an array variable, no matter what
175 IND's value may be. */
177 bind_array_variable (name, ind, value, flags)
185 entry = var_lookup (name, shell_variables);
187 if (entry == (SHELL_VAR *) 0)
188 entry = make_new_array_variable (name);
189 else if (readonly_p (entry) || noassign_p (entry))
191 if (readonly_p (entry))
195 else if (array_p (entry) == 0)
196 entry = convert_var_to_array (entry);
198 /* ENTRY is an array variable, and ARRAY points to the value. */
199 return (bind_array_var_internal (entry, ind, 0, value, flags));
203 bind_array_element (entry, ind, value, flags)
209 return (bind_array_var_internal (entry, ind, 0, value, flags));
213 bind_assoc_variable (entry, name, key, value, flags)
223 if (readonly_p (entry) || noassign_p (entry))
225 if (readonly_p (entry))
230 return (bind_array_var_internal (entry, 0, key, value, flags));
233 /* Parse NAME, a lhs of an assignment statement of the form v[s], and
234 assign VALUE to that array element by calling bind_array_variable(). */
236 assign_array_element (name, value, flags)
240 char *sub, *vname, *akey;
245 vname = array_variable_name (name, &sub, &sublen);
248 return ((SHELL_VAR *)NULL);
250 if ((ALL_ELEMENT_SUB (sub[0]) && sub[1] == ']') || (sublen <= 1))
253 err_badarraysub (name);
254 return ((SHELL_VAR *)NULL);
257 entry = find_variable (vname);
259 if (entry && assoc_p (entry))
261 sub[sublen-1] = '\0';
262 akey = expand_assignment_string_to_string (sub, 0); /* [ */
264 if (akey == 0 || *akey == 0)
267 err_badarraysub (name);
268 return ((SHELL_VAR *)NULL);
270 entry = bind_assoc_variable (entry, vname, akey, value, flags);
274 ind = array_expand_index (sub, sublen);
278 err_badarraysub (name);
279 return ((SHELL_VAR *)NULL);
281 entry = bind_array_variable (vname, ind, value, flags);
288 /* Find the array variable corresponding to NAME. If there is no variable,
289 create a new array variable. If the variable exists but is not an array,
290 convert it to an indexed array. If FLAGS&1 is non-zero, an existing
291 variable is checked for the readonly or noassign attribute in preparation
292 for assignment (e.g., by the `read' builtin). If FLAGS&2 is non-zero, we
293 create an associative array. */
295 find_or_make_array_variable (name, flags)
301 var = find_variable (name);
304 var = (flags & 2) ? make_new_assoc_variable (name) : make_new_array_variable (name);
305 else if ((flags & 1) && (readonly_p (var) || noassign_p (var)))
307 if (readonly_p (var))
309 return ((SHELL_VAR *)NULL);
311 else if ((flags & 2) && array_p (var))
313 report_error (_("%s: cannot convert indexed to associative array"), name);
314 return ((SHELL_VAR *)NULL);
316 else if (array_p (var) == 0 && assoc_p (var) == 0)
317 var = convert_var_to_array (var);
322 /* Perform a compound assignment statement for array NAME, where VALUE is
323 the text between the parens: NAME=( VALUE ) */
325 assign_array_from_string (name, value, flags)
333 if (flags & ASS_MKASSOC)
336 var = find_or_make_array_variable (name, vflags);
338 return ((SHELL_VAR *)NULL);
340 return (assign_array_var_from_string (var, value, flags));
343 /* Sequentially assign the indices of indexed array variable VAR from the
346 assign_array_var_from_word_list (var, list, flags)
351 register arrayind_t i;
352 register WORD_LIST *l;
355 a = array_cell (var);
356 i = (flags & ASS_APPEND) ? array_max_index (a) + 1 : 0;
358 for (l = list; l; l = l->next, i++)
359 if (var->assign_func)
360 (*var->assign_func) (var, l->word->word, i, 0);
362 array_insert (a, i, l->word->word);
367 expand_compound_array_assignment (var, value, flags)
372 WORD_LIST *list, *nlist;
376 /* I don't believe this condition is ever true any more. */
377 if (*value == '(') /*)*/
380 val = extract_array_assignment_list (value, &ni);
382 return (WORD_LIST *)NULL;
387 /* Expand the value string into a list of words, performing all the
388 shell expansions including pathname generation and word splitting. */
389 /* First we split the string on whitespace, using the shell parser
390 (ksh93 seems to do this). */
391 list = parse_string_to_word_list (val, 1, "array assign");
393 /* If we're using [subscript]=value, we need to quote each [ and ] to
394 prevent unwanted filename expansion. */
396 quote_array_assignment_chars (list);
398 /* Now that we've split it, perform the shell expansions on each
400 nlist = list ? expand_words_no_vars (list) : (WORD_LIST *)NULL;
402 dispose_words (list);
410 /* Callers ensure that VAR is not NULL */
412 assign_compound_array_list (var, nlist, flags)
420 char *w, *val, *nval;
422 arrayind_t ind, last_ind;
425 a = (var && array_p (var)) ? array_cell (var) : (ARRAY *)0;
426 h = (var && assoc_p (var)) ? assoc_cell (var) : (HASH_TABLE *)0;
431 /* Now that we are ready to assign values to the array, kill the existing
433 if ((flags & ASS_APPEND) == 0)
435 if (a && array_p (var))
437 else if (h && assoc_p (var))
441 last_ind = (a && (flags & ASS_APPEND)) ? array_max_index (a) + 1 : 0;
443 for (list = nlist; list; list = list->next)
446 w = list->word->word;
448 /* We have a word of the form [ind]=value */
449 if ((list->word->flags & W_ASSIGNMENT) && w[0] == '[')
451 len = skipsubscript (w, 0, (var && assoc_p (var) != 0));
453 /* XXX - changes for `+=' */
454 if (w[len] != ']' || (w[len+1] != '=' && (w[len+1] != '+' || w[len+2] != '=')))
461 nval = make_variable_value (var, w, flags);
462 if (var->assign_func)
463 (*var->assign_func) (var, nval, last_ind, 0);
465 array_insert (a, last_ind, nval);
477 if (ALL_ELEMENT_SUB (w[1]) && len == 2)
480 report_error (_("%s: invalid associative array key"), w);
482 report_error (_("%s: cannot assign to non-numeric index"), w);
488 ind = array_expand_index (w + 1, len);
497 else if (assoc_p (var))
499 akey = substring (w, 1, len);
500 if (akey == 0 || *akey == 0)
507 /* XXX - changes for `+=' -- just accept the syntax. ksh93 doesn't do this */
508 if (w[len + 1] == '+' && w[len + 2] == '=')
510 iflags |= ASS_APPEND;
516 else if (assoc_p (var))
518 report_error (_("%s: %s: must use subscript when assigning associative array"), var->name, w);
521 else /* No [ind]=value, just a stray `=' */
528 this_command_name = (char *)NULL; /* no command name for errors */
529 bind_array_var_internal (var, ind, akey, val, iflags);
534 /* Perform a compound array assignment: VAR->name=( VALUE ). The
535 VALUE has already had the parentheses stripped. */
537 assign_array_var_from_string (var, value, flags)
547 nlist = expand_compound_array_assignment (var, value, flags);
548 assign_compound_array_list (var, nlist, flags);
551 dispose_words (nlist);
555 /* Quote globbing chars and characters in $IFS before the `=' in an assignment
556 statement (usually a compound array assignment) to protect them from
557 unwanted filename expansion or word splitting. */
559 quote_assign (string)
564 char *temp, *t, *subs;
565 const char *s, *send;
569 slen = strlen (string);
570 send = string + slen;
572 t = temp = (char *)xmalloc (slen * 2 + 1);
574 for (s = string; *s; )
578 if (saw_eq == 0 && *s == '[') /* looks like a subscript */
581 se = skipsubscript (string, ss, 0);
582 subs = substring (s, ss, se);
592 if (saw_eq == 0 && (glob_char_p (s) || isifs (*s)))
595 COPY_CHAR_P (t, s, send);
601 /* For each word in a compound array assignment, if the word looks like
602 [ind]=value, quote globbing chars and characters in $IFS before the `='. */
604 quote_array_assignment_chars (list)
610 for (l = list; l; l = l->next)
612 if (l->word == 0 || l->word->word == 0 || l->word->word[0] == '\0')
613 continue; /* should not happen, but just in case... */
614 /* Don't bother if it doesn't look like [ind]=value */
615 if (l->word->word[0] != '[' || mbschr (l->word->word, '=') == 0) /* ] */
617 nword = quote_assign (l->word->word);
618 free (l->word->word);
619 l->word->word = nword;
623 /* skipsubscript moved to subst.c to use private functions. 2009/02/24. */
625 /* This function is called with SUB pointing to just after the beginning
626 `[' of an array subscript and removes the array element to which SUB
627 expands from array VAR. A subscript of `*' or `@' unsets the array. */
629 unbind_array_element (var, sub)
638 len = skipsubscript (sub, 0, 0);
639 if (sub[len] != ']' || len == 0)
641 builtin_error ("%s[%s: %s", var->name, sub, _(bash_badsub_errmsg));
646 if (ALL_ELEMENT_SUB (sub[0]) && sub[1] == 0)
648 unbind_variable (var->name);
654 akey = expand_assignment_string_to_string (sub, 0); /* [ */
655 if (akey == 0 || *akey == 0)
657 builtin_error ("[%s]: %s", sub, _(bash_badsub_errmsg));
660 assoc_remove (assoc_cell (var), akey);
665 ind = array_expand_index (sub, len+1);
668 builtin_error ("[%s]: %s", sub, _(bash_badsub_errmsg));
671 ae = array_remove (array_cell (var), ind);
673 array_dispose_element (ae);
679 /* Format and output an array assignment in compound form VAR=(VALUES),
680 suitable for re-use as input. */
682 print_array_assignment (var, quoted)
688 vstr = array_to_assign (array_cell (var), quoted);
691 printf ("%s=%s\n", var->name, quoted ? "'()'" : "()");
694 printf ("%s=%s\n", var->name, vstr);
699 /* Format and output an associative array assignment in compound form
700 VAR=(VALUES), suitable for re-use as input. */
702 print_assoc_assignment (var, quoted)
708 vstr = assoc_to_assign (assoc_cell (var), quoted);
711 printf ("%s=%s\n", var->name, quoted ? "'()'" : "()");
714 printf ("%s=%s\n", var->name, vstr);
719 /***********************************************************************/
721 /* Utility functions to manage arrays and their contents for expansion */
723 /***********************************************************************/
725 /* Return 1 if NAME is a properly-formed array reference v[sub]. */
727 valid_array_reference (name)
733 t = mbschr (name, '['); /* ] */
737 r = legal_identifier (name);
741 /* Check for a properly-terminated non-blank subscript. */
742 len = skipsubscript (t, 0, 0);
743 if (t[len] != ']' || len == 1)
745 for (r = 1; r < len; r++)
746 if (whitespace (t[r]) == 0)
753 /* Expand the array index beginning at S and extending LEN characters. */
755 array_expand_index (s, len)
763 exp = (char *)xmalloc (len);
764 strncpy (exp, s, len - 1);
766 t = expand_arith_string (exp, 0);
767 this_command_name = (char *)NULL;
768 val = evalexp (t, &expok);
773 last_command_exit_value = EXECUTION_FAILURE;
775 top_level_cleanup ();
776 jump_to_top_level (DISCARD);
781 /* Return the name of the variable specified by S without any subscript.
782 If SUBP is non-null, return a pointer to the start of the subscript
783 in *SUBP. If LENP is non-null, the length of the subscript is returned
784 in *LENP. This returns newly-allocated memory. */
786 array_variable_name (s, subp, lenp)
800 return ((char *)NULL);
803 ni = skipsubscript (s, ind, 0);
804 if (ni <= ind + 1 || s[ni] != ']')
811 return ((char *)NULL);
815 ret = savestring (s);
826 /* Return the variable specified by S without any subscript. If SUBP is
827 non-null, return a pointer to the start of the subscript in *SUBP.
828 If LENP is non-null, the length of the subscript is returned in *LENP. */
830 array_variable_part (s, subp, lenp)
837 t = array_variable_name (s, subp, lenp);
839 return ((SHELL_VAR *)NULL);
840 var = find_variable (t);
843 return (var == 0 || invisible_p (var)) ? (SHELL_VAR *)0 : var;
846 #define INDEX_ERROR() \
850 err_badarraysub (var->name); \
854 err_badarraysub (s); \
855 t[-1] = '['; /* ] */\
857 return ((char *)NULL); \
861 /* Return a string containing the elements in the array and subscript
862 described by S. If the subscript is * or @, obeys quoting rules akin
863 to the expansion of $* and $@ including double quoting. If RTYPE
864 is non-null it gets 1 if the array reference is name[*], 2 if the
865 reference is name[@], and 0 otherwise. */
867 array_value_internal (s, quoted, flags, rtype, indp)
869 int quoted, flags, *rtype;
875 char *retval, *t, *temp;
879 var = array_variable_part (s, &t, &len);
881 /* Expand the index, even if the variable doesn't exist, in case side
882 effects are needed, like ${w[i++]} where w is unset. */
889 return ((char *)NULL); /* error message already printed */
892 if (ALL_ELEMENT_SUB (t[0]) && t[1] == ']')
895 *rtype = (t[0] == '*') ? 1 : 2;
896 if ((flags & AV_ALLOWALL) == 0)
899 return ((char *)NULL);
901 else if (var == 0 || value_cell (var) == 0) /* XXX - check for invisible_p(var) ? */
902 return ((char *)NULL);
903 else if (array_p (var) == 0 && assoc_p (var) == 0)
904 l = add_string_to_list (value_cell (var), (WORD_LIST *)NULL);
905 else if (assoc_p (var))
907 l = assoc_to_word_list (assoc_cell (var));
908 if (l == (WORD_LIST *)NULL)
909 return ((char *)NULL);
913 l = array_to_word_list (array_cell (var));
914 if (l == (WORD_LIST *)NULL)
915 return ((char *) NULL);
918 if (t[0] == '*' && (quoted & (Q_HERE_DOCUMENT|Q_DOUBLE_QUOTES)))
920 temp = string_list_dollar_star (l);
921 retval = quote_string (temp);
924 else /* ${name[@]} or unquoted ${name[*]} */
925 retval = string_list_dollar_at (l, quoted);
933 if (var == 0 || array_p (var) || assoc_p (var) == 0)
935 if ((flags & AV_USEIND) == 0 || indp == 0)
937 ind = array_expand_index (t, len);
940 /* negative subscripts to indexed arrays count back from end */
941 if (var && array_p (var))
942 ind = array_max_index (array_cell (var)) + 1 + ind;
952 else if (assoc_p (var))
955 akey = expand_assignment_string_to_string (t, 0); /* [ */
957 if (akey == 0 || *akey == 0)
961 if (var == 0 || value_cell (var) == 0) /* XXX - check invisible_p(var) ? */
962 return ((char *)NULL);
963 if (array_p (var) == 0 && assoc_p (var) == 0)
964 return (ind == 0 ? value_cell (var) : (char *)NULL);
965 else if (assoc_p (var))
967 retval = assoc_reference (assoc_cell (var), akey);
971 retval = array_reference (array_cell (var), ind);
977 /* Return a string containing the elements described by the array and
978 subscript contained in S, obeying quoting for subscripts * and @. */
980 array_value (s, quoted, flags, rtype, indp)
982 int quoted, flags, *rtype;
985 return (array_value_internal (s, quoted, flags|AV_ALLOWALL, rtype, indp));
988 /* Return the value of the array indexing expression S as a single string.
989 If (FLAGS & AV_ALLOWALL) is 0, do not allow `@' and `*' subscripts. This
990 is used by other parts of the shell such as the arithmetic expression
991 evaluator in expr.c. */
993 get_array_value (s, flags, rtype, indp)
998 return (array_value_internal (s, 0, flags, rtype, indp));
1002 array_keys (s, quoted)
1007 char *retval, *t, *temp;
1011 var = array_variable_part (s, &t, &len);
1014 if (var == 0 || ALL_ELEMENT_SUB (t[0]) == 0 || t[1] != ']')
1015 return (char *)NULL;
1017 if (var_isset (var) == 0 || invisible_p (var))
1018 return (char *)NULL;
1020 if (array_p (var) == 0 && assoc_p (var) == 0)
1021 l = add_string_to_list ("0", (WORD_LIST *)NULL);
1022 else if (assoc_p (var))
1023 l = assoc_keys_to_word_list (assoc_cell (var));
1025 l = array_keys_to_word_list (array_cell (var));
1026 if (l == (WORD_LIST *)NULL)
1027 return ((char *) NULL);
1029 if (t[0] == '*' && (quoted & (Q_HERE_DOCUMENT|Q_DOUBLE_QUOTES)))
1031 temp = string_list_dollar_star (l);
1032 retval = quote_string (temp);
1035 else /* ${!name[@]} or unquoted ${!name[*]} */
1036 retval = string_list_dollar_at (l, quoted);
1041 #endif /* ARRAY_VARS */