1 /* arrayfunc.c -- High-level array functions used by other parts of the shell. */
3 /* Copyright (C) 2001-2003 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 it under
8 the terms of the GNU General Public License as published by the Free
9 Software Foundation; either version 2, or (at your option) any later
12 Bash is distributed in the hope that it will be useful, but WITHOUT ANY
13 WARRANTY; without even the implied warranty of MERCHANTABILITY or
14 FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
17 You should have received a copy of the GNU General Public License along
18 with Bash; see the file COPYING. If not, write to the Free Software
19 Foundation, 59 Temple Place, Suite 330, Boston, MA 02111 USA. */
23 #if defined (ARRAY_VARS)
25 #if defined (HAVE_UNISTD_H)
36 #include "builtins/common.h"
38 extern char *this_command_name;
39 extern int last_command_exit_value;
41 static void quote_array_assignment_chars __P((WORD_LIST *));
42 static char *array_value_internal __P((char *, int, int, int *));
44 /* Standard error message to use when encountering an invalid array subscript */
45 char *bash_badsub_errmsg = N_("bad array subscript");
47 /* **************************************************************** */
49 /* Functions to manipulate array variables and perform assignments */
51 /* **************************************************************** */
53 /* Convert a shell variable to an array variable. The original value is
56 convert_var_to_array (var)
62 oldval = value_cell (var);
63 array = array_create ();
65 array_insert (array, 0, oldval);
67 FREE (value_cell (var));
68 var_setarray (var, array);
70 /* these aren't valid anymore */
71 var->dynamic_value = (sh_var_value_func_t *)NULL;
72 var->assign_func = (sh_var_assign_func_t *)NULL;
74 INVALIDATE_EXPORTSTR (var);
76 VSETATTR (var, att_array);
77 VUNSETATTR (var, att_invisible);
82 /* Perform an array assignment name[ind]=value. If NAME already exists and
83 is not an array, and IND is 0, perform name=value instead. If NAME exists
84 and is not an array, and IND is not 0, convert it into an array with the
85 existing value as name[0].
87 If NAME does not exist, just create an array variable, no matter what
88 IND's value may be. */
90 bind_array_variable (name, ind, value)
98 entry = var_lookup (name, shell_variables);
100 if (entry == (SHELL_VAR *) 0)
101 entry = make_new_array_variable (name);
102 else if (readonly_p (entry) || noassign_p (entry))
104 if (readonly_p (entry))
108 else if (array_p (entry) == 0)
109 entry = convert_var_to_array (entry);
111 /* ENTRY is an array variable, and ARRAY points to the value. */
112 newval = make_variable_value (entry, value);
113 if (entry->assign_func)
114 (*entry->assign_func) (entry, newval, ind);
116 array_insert (array_cell (entry), ind, newval);
122 /* Parse NAME, a lhs of an assignment statement of the form v[s], and
123 assign VALUE to that array element by calling bind_array_variable(). */
125 assign_array_element (name, value)
133 vname = array_variable_name (name, &sub, &sublen);
136 return ((SHELL_VAR *)NULL);
138 if ((ALL_ELEMENT_SUB (sub[0]) && sub[1] == ']') || (sublen <= 1))
141 err_badarraysub (name);
142 return ((SHELL_VAR *)NULL);
145 ind = array_expand_index (sub, sublen);
149 err_badarraysub (name);
150 return ((SHELL_VAR *)NULL);
153 entry = bind_array_variable (vname, ind, value);
159 /* Find the array variable corresponding to NAME. If there is no variable,
160 create a new array variable. If the variable exists but is not an array,
161 convert it to an indexed array. If CHECK_FLAGS is non-zero, an existing
162 variable is checked for the readonly or noassign attribute in preparation
163 for assignment (e.g., by the `read' builtin). */
165 find_or_make_array_variable (name, check_flags)
171 var = find_variable (name);
174 var = make_new_array_variable (name);
175 else if (check_flags && (readonly_p (var) || noassign_p (var)))
177 if (readonly_p (var))
179 return ((SHELL_VAR *)NULL);
181 else if (array_p (var) == 0)
182 var = convert_var_to_array (var);
187 /* Perform a compound assignment statement for array NAME, where VALUE is
188 the text between the parens: NAME=( VALUE ) */
190 assign_array_from_string (name, value)
195 var = find_or_make_array_variable (name, 1);
197 return ((SHELL_VAR *)NULL);
199 return (assign_array_var_from_string (var, value));
202 /* Sequentially assign the indices of indexed array variable VAR from the
205 assign_array_var_from_word_list (var, list)
209 register arrayind_t i;
210 register WORD_LIST *l;
213 for (a = array_cell (var), l = list, i = 0; l; l = l->next, i++)
214 if (var->assign_func)
215 (*var->assign_func) (var, l->word->word, i);
217 array_insert (a, i, l->word->word);
221 /* Perform a compound array assignment: VAR->name=( VALUE ). The
222 VALUE has already had the parentheses stripped. */
224 assign_array_var_from_string (var, value)
229 WORD_LIST *list, *nlist;
230 char *w, *val, *nval;
232 arrayind_t ind, last_ind;
237 /* If this is called from declare_builtin, value[0] == '(' and
238 xstrchr(value, ')') != 0. In this case, we need to extract
239 the value from between the parens before going on. */
240 if (*value == '(') /*)*/
243 val = extract_array_assignment_list (value, &ni);
250 /* Expand the value string into a list of words, performing all the
251 shell expansions including pathname generation and word splitting. */
252 /* First we split the string on whitespace, using the shell parser
253 (ksh93 seems to do this). */
254 list = parse_string_to_word_list (val, 1, "array assign");
256 /* If we're using [subscript]=value, we need to quote each [ and ] to
257 prevent unwanted filename expansion. */
259 quote_array_assignment_chars (list);
261 /* Now that we've split it, perform the shell expansions on each
263 nlist = list ? expand_words_no_vars (list) : (WORD_LIST *)NULL;
265 dispose_words (list);
270 a = array_cell (var);
272 /* Now that we are ready to assign values to the array, kill the existing
277 for (last_ind = 0, list = nlist; list; list = list->next)
279 w = list->word->word;
281 /* We have a word of the form [ind]=value */
282 if ((list->word->flags & W_ASSIGNMENT) && w[0] == '[')
284 len = skipsubscript (w, 0);
286 if (w[len] != ']' || w[len+1] != '=')
288 nval = make_variable_value (var, w);
289 if (var->assign_func)
290 (*var->assign_func) (var, nval, last_ind);
292 array_insert (a, last_ind, nval);
304 if (ALL_ELEMENT_SUB (w[1]) && len == 2)
306 report_error (_("%s: cannot assign to non-numeric index"), w);
310 ind = array_expand_index (w + 1, len);
319 else /* No [ind]=value, just a stray `=' */
326 this_command_name = (char *)NULL; /* no command name for errors */
327 nval = make_variable_value (var, val);
328 if (var->assign_func)
329 (*var->assign_func) (var, nval, ind);
331 array_insert (a, ind, nval);
336 dispose_words (nlist);
340 /* For each word in a compound array assignment, if the word looks like
341 [ind]=value, quote the `[' and `]' before the `=' to protect them from
342 unwanted filename expansion. */
344 quote_array_assignment_chars (list)
351 for (l = list; l; l = l->next)
353 if (l->word == 0 || l->word->word == 0 || l->word->word[0] == '\0')
354 continue; /* should not happen, but just in case... */
355 /* Don't bother if it doesn't look like [ind]=value */
356 if (l->word->word[0] != '[' || xstrchr (l->word->word, '=') == 0) /* ] */
358 s = nword = (char *)xmalloc (strlen (l->word->word) * 2 + 1);
360 for (t = l->word->word; *t; )
364 if (saw_eq == 0 && (*t == '[' || *t == ']'))
369 free (l->word->word);
370 l->word->word = nword;
374 /* This function assumes s[i] == '['; returns with s[ret] == ']' if
375 an array subscript is correctly parsed. */
382 #if defined (HANDLE_MULTIBYTE)
383 mbstate_t state, state_bak;
384 size_t slength, mblength;
388 #if defined (HANDLE_MULTIBYTE)
389 memset (&state, '\0', sizeof (mbstate_t));
390 slength = strlen (s + i);
391 mb_cur_max = MB_CUR_MAX;
397 /* Advance one (possibly multibyte) character in S starting at I. */
398 #if defined (HANDLE_MULTIBYTE)
402 mblength = mbrlen (s + i, slength, &state);
404 if (MB_INVALIDCH (mblength))
410 else if (MB_NULLWCH (mblength))
435 /* This function is called with SUB pointing to just after the beginning
436 `[' of an array subscript and removes the array element to which SUB
437 expands from array VAR. A subscript of `*' or `@' unsets the array. */
439 unbind_array_element (var, sub)
447 len = skipsubscript (sub, 0);
448 if (sub[len] != ']' || len == 0)
450 builtin_error ("%s[%s: %s", var->name, sub, _(bash_badsub_errmsg));
455 if (ALL_ELEMENT_SUB (sub[0]) && sub[1] == 0)
457 unbind_variable (var->name);
460 ind = array_expand_index (sub, len+1);
463 builtin_error ("[%s]: %s", sub, _(bash_badsub_errmsg));
466 ae = array_remove (array_cell (var), ind);
468 array_dispose_element (ae);
472 /* Format and output an array assignment in compound form VAR=(VALUES),
473 suitable for re-use as input. */
475 print_array_assignment (var, quoted)
481 vstr = array_to_assign (array_cell (var), quoted);
484 printf ("%s=%s\n", var->name, quoted ? "'()'" : "()");
487 printf ("%s=%s\n", var->name, vstr);
492 /***********************************************************************/
494 /* Utility functions to manage arrays and their contents for expansion */
496 /***********************************************************************/
498 /* Return 1 if NAME is a properly-formed array reference v[sub]. */
500 valid_array_reference (name)
506 t = xstrchr (name, '['); /* ] */
510 r = legal_identifier (name);
514 /* Check for a properly-terminated non-blank subscript. */
515 len = skipsubscript (t, 0);
516 if (t[len] != ']' || len == 1)
518 for (r = 1; r < len; r++)
519 if (whitespace (t[r]) == 0)
526 /* Expand the array index beginning at S and extending LEN characters. */
528 array_expand_index (s, len)
536 exp = (char *)xmalloc (len);
537 strncpy (exp, s, len - 1);
539 t = expand_string_to_string (exp, 0);
540 this_command_name = (char *)NULL;
541 val = evalexp (t, &expok);
546 last_command_exit_value = EXECUTION_FAILURE;
547 jump_to_top_level (DISCARD);
552 /* Return the name of the variable specified by S without any subscript.
553 If SUBP is non-null, return a pointer to the start of the subscript
554 in *SUBP. If LENP is non-null, the length of the subscript is returned
555 in *LENP. This returns newly-allocated memory. */
557 array_variable_name (s, subp, lenp)
564 t = xstrchr (s, '[');
571 return ((char *)NULL);
574 ni = skipsubscript (s, ind);
575 if (ni <= ind + 1 || s[ni] != ']')
582 return ((char *)NULL);
586 ret = savestring (s);
597 /* Return the variable specified by S without any subscript. If SUBP is
598 non-null, return a pointer to the start of the subscript in *SUBP.
599 If LENP is non-null, the length of the subscript is returned in *LENP. */
601 array_variable_part (s, subp, lenp)
608 t = array_variable_name (s, subp, lenp);
610 return ((SHELL_VAR *)NULL);
611 var = find_variable (t);
614 return (var == 0 || invisible_p (var)) ? (SHELL_VAR *)0 : var;
617 /* Return a string containing the elements in the array and subscript
618 described by S. If the subscript is * or @, obeys quoting rules akin
619 to the expansion of $* and $@ including double quoting. If RTYPE
620 is non-null it gets 1 if the array reference is name[@] or name[*]
623 array_value_internal (s, quoted, allow_all, rtype)
625 int quoted, allow_all, *rtype;
629 char *retval, *t, *temp;
633 var = array_variable_part (s, &t, &len);
635 /* Expand the index, even if the variable doesn't exist, in case side
636 effects are needed, like ${w[i++]} where w is unset. */
643 return ((char *)NULL); /* error message already printed */
646 if (ALL_ELEMENT_SUB (t[0]) && t[1] == ']')
653 return ((char *)NULL);
656 return ((char *)NULL);
657 else if (array_p (var) == 0)
658 l = add_string_to_list (value_cell (var), (WORD_LIST *)NULL);
661 l = array_to_word_list (array_cell (var));
662 if (l == (WORD_LIST *)NULL)
663 return ((char *) NULL);
666 if (t[0] == '*' && (quoted & (Q_HERE_DOCUMENT|Q_DOUBLE_QUOTES)))
668 temp = string_list_dollar_star (l);
669 retval = quote_string (temp);
672 else /* ${name[@]} or unquoted ${name[*]} */
673 retval = string_list_dollar_at (l, quoted);
681 ind = array_expand_index (t, len);
685 err_badarraysub (var->name);
692 return ((char *)NULL);
695 return ((char *)NULL);
696 if (array_p (var) == 0)
697 return (ind == 0 ? value_cell (var) : (char *)NULL);
698 retval = array_reference (array_cell (var), ind);
704 /* Return a string containing the elements described by the array and
705 subscript contained in S, obeying quoting for subscripts * and @. */
707 array_value (s, quoted, rtype)
711 return (array_value_internal (s, quoted, 1, rtype));
714 /* Return the value of the array indexing expression S as a single string.
715 If ALLOW_ALL is 0, do not allow `@' and `*' subscripts. This is used
716 by other parts of the shell such as the arithmetic expression evaluator
719 get_array_value (s, allow_all, rtype)
721 int allow_all, *rtype;
723 return (array_value_internal (s, 0, allow_all, rtype));
727 array_keys (s, quoted)
732 char *retval, *t, *temp;
736 var = array_variable_part (s, &t, &len);
739 if (var == 0 || ALL_ELEMENT_SUB (t[0]) == 0 || t[1] != ']')
742 if (array_p (var) == 0)
743 l = add_string_to_list ("0", (WORD_LIST *)NULL);
746 l = array_keys_to_word_list (array_cell (var));
747 if (l == (WORD_LIST *)NULL)
748 return ((char *) NULL);
751 if (t[0] == '*' && (quoted & (Q_HERE_DOCUMENT|Q_DOUBLE_QUOTES)))
753 temp = string_list_dollar_star (l);
754 retval = quote_string (temp);
757 else /* ${!name[@]} or unquoted ${!name[*]} */
758 retval = string_list_dollar_at (l, quoted);
763 #endif /* ARRAY_VARS */