arrayfunc.c

   1 /* arrayfunc.c -- High-level array functions used by other parts of the shell. */
   2
   3 /* Copyright (C) 2001-2011 Free Software Foundation, Inc.
   4
   5    This file is part of GNU Bash, the Bourne Again SHell.
   6
   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.
  11
  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.
  16
  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/>.
  19 */
  20
  21 #include "config.h"
  22
  23 #if defined (ARRAY_VARS)
  24
  25 #if defined (HAVE_UNISTD_H)
  26 #  include <unistd.h>
  27 #endif
  28 #include <stdio.h>
  29
  30 #include "bashintl.h"
  31
  32 #include "shell.h"
  33 #include "pathexp.h"
  34
  35 #include "shmbutil.h"
  36
  37 #include "builtins/common.h"
  38
  39 extern char *this_command_name;
  40 extern int last_command_exit_value;
  41 extern int array_needs_making;
  42
  43 static SHELL_VAR *bind_array_var_internal __P((SHELL_VAR *, arrayind_t, char *, char *, int));
  44 static SHELL_VAR *assign_array_element_internal __P((SHELL_VAR *, char *, char *, char *, int, char *, int));
  45
  46 static char *quote_assign __P((const char *));
  47 static void quote_array_assignment_chars __P((WORD_LIST *));
  48 static char *array_value_internal __P((char *, int, int, int *, arrayind_t *));
  49
  50 /* Standard error message to use when encountering an invalid array subscript */
  51 const char * const bash_badsub_errmsg = N_("bad array subscript");
  52
  53 /* **************************************************************** */
  54 /*                                                                  */
  55 /*  Functions to manipulate array variables and perform assignments */
  56 /*                                                                  */
  57 /* **************************************************************** */
  58
  59 /* Convert a shell variable to an array variable.  The original value is
  60    saved as array[0]. */
  61 SHELL_VAR *
  62 convert_var_to_array (var)
  63      SHELL_VAR *var;
  64 {
  65   char *oldval;
  66   ARRAY *array;
  67
  68   oldval = value_cell (var);
  69   array = array_create ();
  70   if (oldval)
  71     array_insert (array, 0, oldval);
  72
  73   FREE (value_cell (var));
  74   var_setarray (var, array);
  75
  76   /* these aren't valid anymore */
  77   var->dynamic_value = (sh_var_value_func_t *)NULL;
  78   var->assign_func = (sh_var_assign_func_t *)NULL;
  79
  80   INVALIDATE_EXPORTSTR (var);
  81   if (exported_p (var))
  82     array_needs_making++;
  83
  84   VSETATTR (var, att_array);
  85   VUNSETATTR (var, att_invisible);
  86
  87   return var;
  88 }
  89
  90 /* Convert a shell variable to an array variable.  The original value is
  91    saved as array[0]. */
  92 SHELL_VAR *
  93 convert_var_to_assoc (var)
  94      SHELL_VAR *var;
  95 {
  96   char *oldval;
  97   HASH_TABLE *hash;
  98
  99   oldval = value_cell (var);
 100   hash = assoc_create (0);
 101   if (oldval)
 102     assoc_insert (hash, savestring ("0"), oldval);
 103
 104   FREE (value_cell (var));
 105   var_setassoc (var, hash);
 106
 107   /* these aren't valid anymore */
 108   var->dynamic_value = (sh_var_value_func_t *)NULL;
 109   var->assign_func = (sh_var_assign_func_t *)NULL;
 110
 111   INVALIDATE_EXPORTSTR (var);
 112   if (exported_p (var))
 113     array_needs_making++;
 114
 115   VSETATTR (var, att_assoc);
 116   VUNSETATTR (var, att_invisible);
 117
 118   return var;
 119 }
 120
 121 char *
 122 make_array_variable_value (entry, ind, key, value, flags)
 123      SHELL_VAR *entry;
 124      arrayind_t ind;
 125      char *key;
 126      char *value;
 127      int flags;
 128 {
 129   SHELL_VAR *dentry;
 130   char *newval;
 131
 132   /* If we're appending, we need the old value of the array reference, so
 133      fake out make_variable_value with a dummy SHELL_VAR */
 134   if (flags & ASS_APPEND)
 135     {
 136       dentry = (SHELL_VAR *)xmalloc (sizeof (SHELL_VAR));
 137       dentry->name = savestring (entry->name);
 138       if (assoc_p (entry))
 139         newval = assoc_reference (assoc_cell (entry), key);
 140       else
 141         newval = array_reference (array_cell (entry), ind);
 142       if (newval)
 143         dentry->value = savestring (newval);
 144       else
 145         {
 146           dentry->value = (char *)xmalloc (1);
 147           dentry->value[0] = '\0';
 148         }
 149       dentry->exportstr = 0;
 150       dentry->attributes = entry->attributes & ~(att_array|att_assoc|att_exported);
 151       /* Leave the rest of the members uninitialized; the code doesn't look
 152          at them. */
 153       newval = make_variable_value (dentry, value, flags);
 154       dispose_variable (dentry);
 155     }
 156   else
 157     newval = make_variable_value (entry, value, flags);
 158
 159   return newval;
 160 }
 161
 162 static SHELL_VAR *
 163 bind_array_var_internal (entry, ind, key, value, flags)
 164      SHELL_VAR *entry;
 165      arrayind_t ind;
 166      char *key;
 167      char *value;
 168      int flags;
 169 {
 170   char *newval;
 171
 172   newval = make_array_variable_value (entry, ind, key, value, flags);
 173
 174   if (entry->assign_func)
 175     (*entry->assign_func) (entry, newval, ind, key);
 176   else if (assoc_p (entry))
 177     assoc_insert (assoc_cell (entry), key, newval);
 178   else
 179     array_insert (array_cell (entry), ind, newval);
 180   FREE (newval);
 181
 182   return (entry);
 183 }
 184
 185 /* Perform an array assignment name[ind]=value.  If NAME already exists and
 186    is not an array, and IND is 0, perform name=value instead.  If NAME exists
 187    and is not an array, and IND is not 0, convert it into an array with the
 188    existing value as name[0].
 189
 190    If NAME does not exist, just create an array variable, no matter what
 191    IND's value may be. */
 192 SHELL_VAR *
 193 bind_array_variable (name, ind, value, flags)
 194      char *name;
 195      arrayind_t ind;
 196      char *value;
 197      int flags;
 198 {
 199   SHELL_VAR *entry;
 200
 201   entry = find_shell_variable (name);
 202
 203   if (entry == (SHELL_VAR *) 0)
 204     entry = make_new_array_variable (name);
 205   else if (readonly_p (entry) || noassign_p (entry))
 206     {
 207       if (readonly_p (entry))
 208         err_readonly (name);
 209       return (entry);
 210     }
 211   else if (array_p (entry) == 0)
 212     entry = convert_var_to_array (entry);
 213
 214   /* ENTRY is an array variable, and ARRAY points to the value. */
 215   return (bind_array_var_internal (entry, ind, 0, value, flags));
 216 }
 217
 218 SHELL_VAR *
 219 bind_array_element (entry, ind, value, flags)
 220      SHELL_VAR *entry;
 221      arrayind_t ind;
 222      char *value;
 223      int flags;
 224 {
 225   return (bind_array_var_internal (entry, ind, 0, value, flags));
 226 }
 227
 228 SHELL_VAR *
 229 bind_assoc_variable (entry, name, key, value, flags)
 230      SHELL_VAR *entry;
 231      char *name;
 232      char *key;
 233      char *value;
 234      int flags;
 235 {
 236   SHELL_VAR *dentry;
 237   char *newval;
 238
 239   if (readonly_p (entry) || noassign_p (entry))
 240     {
 241       if (readonly_p (entry))
 242         err_readonly (name);
 243       return (entry);
 244     }
 245
 246   return (bind_array_var_internal (entry, 0, key, value, flags));
 247 }
 248
 249 /* Parse NAME, a lhs of an assignment statement of the form v[s], and
 250    assign VALUE to that array element by calling bind_array_variable(). */
 251 SHELL_VAR *
 252 assign_array_element (name, value, flags)
 253      char *name, *value;
 254      int flags;
 255 {
 256   char *sub, *vname;
 257   int sublen;
 258   SHELL_VAR *entry;
 259
 260   vname = array_variable_name (name, &sub, &sublen);
 261
 262   if (vname == 0)
 263     return ((SHELL_VAR *)NULL);
 264
 265   if ((ALL_ELEMENT_SUB (sub[0]) && sub[1] == ']') || (sublen <= 1))
 266     {
 267       free (vname);
 268       err_badarraysub (name);
 269       return ((SHELL_VAR *)NULL);
 270     }
 271
 272   entry = find_variable (vname);
 273   entry = assign_array_element_internal (entry, name, vname, sub, sublen, value, flags);
 274
 275   free (vname);
 276   return entry;
 277 }
 278
 279 static SHELL_VAR *
 280 assign_array_element_internal (entry, name, vname, sub, sublen, value, flags)
 281      SHELL_VAR *entry;
 282      char *name;                /* only used for error messages */
 283      char *vname;
 284      char *sub;
 285      int sublen;
 286      char *value;
 287      int flags;
 288 {
 289   char *akey;
 290   arrayind_t ind;
 291
 292   if (entry && assoc_p (entry))
 293     {
 294       sub[sublen-1] = '\0';
 295       akey = expand_assignment_string_to_string (sub, 0);       /* [ */
 296       sub[sublen-1] = ']';
 297       if (akey == 0 || *akey == 0)
 298         {
 299           err_badarraysub (name);
 300           FREE (akey);
 301           return ((SHELL_VAR *)NULL);
 302         }
 303       entry = bind_assoc_variable (entry, vname, akey, value, flags);
 304     }
 305   else
 306     {
 307       ind = array_expand_index (entry, sub, sublen);
 308       if (ind < 0)
 309         {
 310           err_badarraysub (name);
 311           return ((SHELL_VAR *)NULL);
 312         }
 313       entry = bind_array_variable (vname, ind, value, flags);
 314     }
 315
 316   return (entry);
 317 }
 318
 319 /* Find the array variable corresponding to NAME.  If there is no variable,
 320    create a new array variable.  If the variable exists but is not an array,
 321    convert it to an indexed array.  If FLAGS&1 is non-zero, an existing
 322    variable is checked for the readonly or noassign attribute in preparation
 323    for assignment (e.g., by the `read' builtin).  If FLAGS&2 is non-zero, we
 324    create an associative array. */
 325 SHELL_VAR *
 326 find_or_make_array_variable (name, flags)
 327      char *name;
 328      int flags;
 329 {
 330   SHELL_VAR *var;
 331
 332   var = find_variable (name);
 333   if (var == 0)
 334     {
 335       /* See if we have a nameref pointing to a variable that hasn't been
 336          created yet. */
 337       var = find_variable_last_nameref (name);
 338       if (var && nameref_p (var))
 339         var = (flags & 2) ? make_new_assoc_variable (nameref_cell (var)) : make_new_array_variable (nameref_cell (var));
 340     }
 341
 342   if (var == 0)
 343     var = (flags & 2) ? make_new_assoc_variable (name) : make_new_array_variable (name);
 344   else if ((flags & 1) && (readonly_p (var) || noassign_p (var)))
 345     {
 346       if (readonly_p (var))
 347         err_readonly (name);
 348       return ((SHELL_VAR *)NULL);
 349     }
 350   else if ((flags & 2) && array_p (var))
 351     {
 352       last_command_exit_value = 1;
 353       report_error (_("%s: cannot convert indexed to associative array"), name);
 354       return ((SHELL_VAR *)NULL);
 355     }
 356   else if (array_p (var) == 0 && assoc_p (var) == 0)
 357     var = convert_var_to_array (var);
 358
 359   return (var);
 360 }
 361
 362 /* Perform a compound assignment statement for array NAME, where VALUE is
 363    the text between the parens:  NAME=( VALUE ) */
 364 SHELL_VAR *
 365 assign_array_from_string (name, value, flags)
 366      char *name, *value;
 367      int flags;
 368 {
 369   SHELL_VAR *var;
 370   int vflags;
 371
 372   vflags = 1;
 373   if (flags & ASS_MKASSOC)
 374     vflags |= 2;
 375
 376   var = find_or_make_array_variable (name, vflags);
 377   if (var == 0)
 378     return ((SHELL_VAR *)NULL);
 379
 380   return (assign_array_var_from_string (var, value, flags));
 381 }
 382
 383 /* Sequentially assign the indices of indexed array variable VAR from the
 384    words in LIST. */
 385 SHELL_VAR *
 386 assign_array_var_from_word_list (var, list, flags)
 387      SHELL_VAR *var;
 388      WORD_LIST *list;
 389      int flags;
 390 {
 391   register arrayind_t i;
 392   register WORD_LIST *l;
 393   ARRAY *a;
 394
 395   a = array_cell (var);
 396   i = (flags & ASS_APPEND) ? array_max_index (a) + 1 : 0;
 397
 398   for (l = list; l; l = l->next, i++)
 399     if (var->assign_func)
 400       (*var->assign_func) (var, l->word->word, i, 0);
 401     else
 402       array_insert (a, i, l->word->word);
 403   return var;
 404 }
 405
 406 WORD_LIST *
 407 expand_compound_array_assignment (var, value, flags)
 408      SHELL_VAR *var;
 409      char *value;
 410      int flags;
 411 {
 412   WORD_LIST *list, *nlist;
 413   WORD_LIST *hd, *tl, *t, *n;
 414   char *val;
 415   int ni;
 416
 417   /* This condition is true when invoked from the declare builtin with a
 418      command like
 419         declare -a d='([1]="" [2]="bdef" [5]="hello world" "test")' */
 420   if (*value == '(')    /*)*/
 421     {
 422       ni = 1;
 423       val = extract_array_assignment_list (value, &ni);
 424       if (val == 0)
 425         return (WORD_LIST *)NULL;
 426     }
 427   else
 428     val = value;
 429
 430   /* Expand the value string into a list of words, performing all the
 431      shell expansions including pathname generation and word splitting. */
 432   /* First we split the string on whitespace, using the shell parser
 433      (ksh93 seems to do this). */
 434   list = parse_string_to_word_list (val, 1, "array assign");
 435
 436   if (var && assoc_p (var))
 437     {
 438       if (val != value)
 439         free (val);
 440       return list;
 441     }
 442
 443   /* If we're using [subscript]=value, we need to quote each [ and ] to
 444      prevent unwanted filename expansion.  This doesn't need to be done
 445      for associative array expansion, since that uses a different expansion
 446      function (see assign_compound_array_list below). */
 447   if (list)
 448     quote_array_assignment_chars (list);
 449
 450   /* Now that we've split it, perform the shell expansions on each
 451      word in the list. */
 452   nlist = list ? expand_words_no_vars (list) : (WORD_LIST *)NULL;
 453
 454   dispose_words (list);
 455
 456   if (val != value)
 457     free (val);
 458
 459   return nlist;
 460 }
 461
 462 /* Callers ensure that VAR is not NULL */
 463 void
 464 assign_compound_array_list (var, nlist, flags)
 465      SHELL_VAR *var;
 466      WORD_LIST *nlist;
 467      int flags;
 468 {
 469   ARRAY *a;
 470   HASH_TABLE *h;
 471   WORD_LIST *list;
 472   char *w, *val, *nval;
 473   int len, iflags, free_val;
 474   arrayind_t ind, last_ind;
 475   char *akey;
 476
 477   a = (var && array_p (var)) ? array_cell (var) : (ARRAY *)0;
 478   h = (var && assoc_p (var)) ? assoc_cell (var) : (HASH_TABLE *)0;
 479
 480   akey = (char *)0;
 481   ind = 0;
 482
 483   /* Now that we are ready to assign values to the array, kill the existing
 484      value. */
 485   if ((flags & ASS_APPEND) == 0)
 486     {
 487       if (a && array_p (var))
 488         array_flush (a);
 489       else if (h && assoc_p (var))
 490         assoc_flush (h);
 491     }
 492
 493   last_ind = (a && (flags & ASS_APPEND)) ? array_max_index (a) + 1 : 0;
 494
 495   for (list = nlist; list; list = list->next)
 496     {
 497       iflags = flags;
 498       w = list->word->word;
 499
 500       /* We have a word of the form [ind]=value */
 501       if ((list->word->flags & W_ASSIGNMENT) && w[0] == '[')
 502         {
 503           /* Don't have to handle embedded quotes specially any more, since
 504              associative array subscripts have not been expanded yet (see
 505              above). */
 506           len = skipsubscript (w, 0, 0);
 507
 508           /* XXX - changes for `+=' */
 509           if (w[len] != ']' || (w[len+1] != '=' && (w[len+1] != '+' || w[len+2] != '=')))
 510             {
 511               if (assoc_p (var))
 512                 {
 513                   err_badarraysub (w);
 514                   continue;
 515                 }
 516               nval = make_variable_value (var, w, flags);
 517               if (var->assign_func)
 518                 (*var->assign_func) (var, nval, last_ind, 0);
 519               else
 520                 array_insert (a, last_ind, nval);
 521               FREE (nval);
 522               last_ind++;
 523               continue;
 524             }
 525
 526           if (len == 1)
 527             {
 528               err_badarraysub (w);
 529               continue;
 530             }
 531
 532           if (ALL_ELEMENT_SUB (w[1]) && len == 2)
 533             {
 534               last_command_exit_value = 1;
 535               if (assoc_p (var))
 536                 report_error (_("%s: invalid associative array key"), w);
 537               else
 538                 report_error (_("%s: cannot assign to non-numeric index"), w);
 539               continue;
 540             }
 541
 542           if (array_p (var))
 543             {
 544               ind = array_expand_index (var, w + 1, len);
 545               if (ind < 0)
 546                 {
 547                   err_badarraysub (w);
 548                   continue;
 549                 }
 550
 551               last_ind = ind;
 552             }
 553           else if (assoc_p (var))
 554             {
 555               /* This is not performed above, see expand_compound_array_assignment */
 556               w[len] = '\0';    /*[*/
 557               akey = expand_assignment_string_to_string (w+1, 0);
 558               w[len] = ']';
 559               /* And we need to expand the value also, see below */
 560               if (akey == 0 || *akey == 0)
 561                 {
 562                   err_badarraysub (w);
 563                   FREE (akey);
 564                   continue;
 565                 }
 566             }
 567
 568           /* XXX - changes for `+=' -- just accept the syntax.  ksh93 doesn't do this */
 569           if (w[len + 1] == '+' && w[len + 2] == '=')
 570             {
 571               iflags |= ASS_APPEND;
 572               val = w + len + 3;
 573             }
 574           else
 575             val = w + len + 2;
 576         }
 577       else if (assoc_p (var))
 578         {
 579           last_command_exit_value = 1;
 580           report_error (_("%s: %s: must use subscript when assigning associative array"), var->name, w);
 581           continue;
 582         }
 583       else              /* No [ind]=value, just a stray `=' */
 584         {
 585           ind = last_ind;
 586           val = w;
 587         }
 588
 589       free_val = 0;
 590       /* See above; we need to expand the value here */
 591       if (assoc_p (var))
 592         {
 593           val = expand_assignment_string_to_string (val, 0);
 594           free_val = 1;
 595         }
 596
 597       if (integer_p (var))
 598         this_command_name = (char *)NULL;       /* no command name for errors */
 599       bind_array_var_internal (var, ind, akey, val, iflags);
 600       last_ind++;
 601
 602       if (free_val)
 603         free (val);
 604     }
 605 }
 606
 607 /* Perform a compound array assignment:  VAR->name=( VALUE ).  The
 608    VALUE has already had the parentheses stripped. */
 609 SHELL_VAR *
 610 assign_array_var_from_string (var, value, flags)
 611      SHELL_VAR *var;
 612      char *value;
 613      int flags;
 614 {
 615   WORD_LIST *nlist;
 616
 617   if (value == 0)
 618     return var;
 619
 620   nlist = expand_compound_array_assignment (var, value, flags);
 621   assign_compound_array_list (var, nlist, flags);
 622
 623   if (nlist)
 624     dispose_words (nlist);
 625   return (var);
 626 }
 627
 628 /* Quote globbing chars and characters in $IFS before the `=' in an assignment
 629    statement (usually a compound array assignment) to protect them from
 630    unwanted filename expansion or word splitting. */
 631 static char *
 632 quote_assign (string)
 633      const char *string;
 634 {
 635   size_t slen;
 636   int saw_eq;
 637   char *temp, *t, *subs;
 638   const char *s, *send;
 639   int ss, se;
 640   DECLARE_MBSTATE;
 641
 642   slen = strlen (string);
 643   send = string + slen;
 644
 645   t = temp = (char *)xmalloc (slen * 2 + 1);
 646   saw_eq = 0;
 647   for (s = string; *s; )
 648     {
 649       if (*s == '=')
 650         saw_eq = 1;
 651       if (saw_eq == 0 && *s == '[')             /* looks like a subscript */
 652         {
 653           ss = s - string;
 654           se = skipsubscript (string, ss, 0);
 655           subs = substring (s, ss, se);
 656           *t++ = '\\';
 657           strcpy (t, subs);
 658           t += se - ss;
 659           *t++ = '\\';
 660           *t++ = ']';
 661           s += se + 1;
 662           free (subs);
 663           continue;
 664         }
 665       if (saw_eq == 0 && (glob_char_p (s) || isifs (*s)))
 666         *t++ = '\\';
 667
 668       COPY_CHAR_P (t, s, send);
 669     }
 670   *t = '\0';
 671   return temp;
 672 }
 673
 674 /* For each word in a compound array assignment, if the word looks like
 675    [ind]=value, quote globbing chars and characters in $IFS before the `='. */
 676 static void
 677 quote_array_assignment_chars (list)
 678      WORD_LIST *list;
 679 {
 680   char *nword;
 681   WORD_LIST *l;
 682
 683   for (l = list; l; l = l->next)
 684     {
 685       if (l->word == 0 || l->word->word == 0 || l->word->word[0] == '\0')
 686         continue;       /* should not happen, but just in case... */
 687       /* Don't bother if it hasn't been recognized as an assignment or
 688          doesn't look like [ind]=value */
 689       if ((l->word->flags & W_ASSIGNMENT) == 0)
 690         continue;
 691       if (l->word->word[0] != '[' || mbschr (l->word->word, '=') == 0) /* ] */
 692         continue;
 693
 694       nword = quote_assign (l->word->word);
 695       free (l->word->word);
 696       l->word->word = nword;
 697       l->word->flags |= W_NOGLOB;       /* XXX - W_NOSPLIT also? */
 698     }
 699 }
 700
 701 /* skipsubscript moved to subst.c to use private functions. 2009/02/24. */
 702
 703 /* This function is called with SUB pointing to just after the beginning
 704    `[' of an array subscript and removes the array element to which SUB
 705    expands from array VAR.  A subscript of `*' or `@' unsets the array. */
 706 int
 707 unbind_array_element (var, sub)
 708      SHELL_VAR *var;
 709      char *sub;
 710 {
 711   int len;
 712   arrayind_t ind;
 713   char *akey;
 714   ARRAY_ELEMENT *ae;
 715
 716   len = skipsubscript (sub, 0, 0);
 717   if (sub[len] != ']' || len == 0)
 718     {
 719       builtin_error ("%s[%s: %s", var->name, sub, _(bash_badsub_errmsg));
 720       return -1;
 721     }
 722   sub[len] = '\0';
 723
 724   if (ALL_ELEMENT_SUB (sub[0]) && sub[1] == 0)
 725     {
 726       unbind_variable (var->name);
 727       return (0);
 728     }
 729
 730   if (assoc_p (var))
 731     {
 732       akey = expand_assignment_string_to_string (sub, 0);     /* [ */
 733       if (akey == 0 || *akey == 0)
 734         {
 735           builtin_error ("[%s]: %s", sub, _(bash_badsub_errmsg));
 736           FREE (akey);
 737           return -1;
 738         }
 739       assoc_remove (assoc_cell (var), akey);
 740       free (akey);
 741     }
 742   else
 743     {
 744       ind = array_expand_index (var, sub, len+1);
 745       if (ind < 0)
 746         {
 747           builtin_error ("[%s]: %s", sub, _(bash_badsub_errmsg));
 748           return -1;
 749         }
 750       ae = array_remove (array_cell (var), ind);
 751       if (ae)
 752         array_dispose_element (ae);
 753     }
 754
 755   return 0;
 756 }
 757
 758 /* Format and output an array assignment in compound form VAR=(VALUES),
 759    suitable for re-use as input. */
 760 void
 761 print_array_assignment (var, quoted)
 762      SHELL_VAR *var;
 763      int quoted;
 764 {
 765   char *vstr;
 766
 767   vstr = array_to_assign (array_cell (var), quoted);
 768
 769   if (vstr == 0)
 770     printf ("%s=%s\n", var->name, quoted ? "'()'" : "()");
 771   else
 772     {
 773       printf ("%s=%s\n", var->name, vstr);
 774       free (vstr);
 775     }
 776 }
 777
 778 /* Format and output an associative array assignment in compound form
 779    VAR=(VALUES), suitable for re-use as input. */
 780 void
 781 print_assoc_assignment (var, quoted)
 782      SHELL_VAR *var;
 783      int quoted;
 784 {
 785   char *vstr;
 786
 787   vstr = assoc_to_assign (assoc_cell (var), quoted);
 788
 789   if (vstr == 0)
 790     printf ("%s=%s\n", var->name, quoted ? "'()'" : "()");
 791   else
 792     {
 793       printf ("%s=%s\n", var->name, vstr);
 794       free (vstr);
 795     }
 796 }
 797
 798 /***********************************************************************/
 799 /*                                                                     */
 800 /* Utility functions to manage arrays and their contents for expansion */
 801 /*                                                                     */
 802 /***********************************************************************/
 803
 804 /* Return 1 if NAME is a properly-formed array reference v[sub]. */
 805 int
 806 valid_array_reference (name)
 807      char *name;
 808 {
 809   char *t;
 810   int r, len;
 811
 812   t = mbschr (name, '[');       /* ] */
 813   if (t)
 814     {
 815       *t = '\0';
 816       r = legal_identifier (name);
 817       *t = '[';
 818       if (r == 0)
 819         return 0;
 820       /* Check for a properly-terminated non-blank subscript. */
 821       len = skipsubscript (t, 0, 0);
 822       if (t[len] != ']' || len == 1)
 823         return 0;
 824       for (r = 1; r < len; r++)
 825         if (whitespace (t[r]) == 0)
 826           return 1;
 827       return 0;
 828     }
 829   return 0;
 830 }
 831
 832 /* Expand the array index beginning at S and extending LEN characters. */
 833 arrayind_t
 834 array_expand_index (var, s, len)
 835      SHELL_VAR *var;
 836      char *s;
 837      int len;
 838 {
 839   char *exp, *t;
 840   int expok;
 841   arrayind_t val;
 842
 843   exp = (char *)xmalloc (len);
 844   strncpy (exp, s, len - 1);
 845   exp[len - 1] = '\0';
 846   t = expand_arith_string (exp, 0);
 847   this_command_name = (char *)NULL;
 848   val = evalexp (t, &expok);
 849   free (t);
 850   free (exp);
 851   if (expok == 0)
 852     {
 853       last_command_exit_value = EXECUTION_FAILURE;
 854
 855       top_level_cleanup ();
 856       jump_to_top_level (DISCARD);
 857     }
 858   return val;
 859 }
 860
 861 /* Return the name of the variable specified by S without any subscript.
 862    If SUBP is non-null, return a pointer to the start of the subscript
 863    in *SUBP. If LENP is non-null, the length of the subscript is returned
 864    in *LENP.  This returns newly-allocated memory. */
 865 char *
 866 array_variable_name (s, subp, lenp)
 867      char *s, **subp;
 868      int *lenp;
 869 {
 870   char *t, *ret;
 871   int ind, ni;
 872
 873   t = mbschr (s, '[');
 874   if (t == 0)
 875     {
 876       if (subp)
 877         *subp = t;
 878       if (lenp)
 879         *lenp = 0;
 880       return ((char *)NULL);
 881     }
 882   ind = t - s;
 883   ni = skipsubscript (s, ind, 0);
 884   if (ni <= ind + 1 || s[ni] != ']')
 885     {
 886       err_badarraysub (s);
 887       if (subp)
 888         *subp = t;
 889       if (lenp)
 890         *lenp = 0;
 891       return ((char *)NULL);
 892     }
 893
 894   *t = '\0';
 895   ret = savestring (s);
 896   *t++ = '[';           /* ] */
 897
 898   if (subp)
 899     *subp = t;
 900   if (lenp)
 901     *lenp = ni - ind;
 902
 903   return ret;
 904 }
 905
 906 /* Return the variable specified by S without any subscript.  If SUBP is
 907    non-null, return a pointer to the start of the subscript in *SUBP.
 908    If LENP is non-null, the length of the subscript is returned in *LENP. */
 909 SHELL_VAR *
 910 array_variable_part (s, subp, lenp)
 911      char *s, **subp;
 912      int *lenp;
 913 {
 914   char *t;
 915   SHELL_VAR *var;
 916
 917   t = array_variable_name (s, subp, lenp);
 918   if (t == 0)
 919     return ((SHELL_VAR *)NULL);
 920   var = find_variable (t);
 921
 922   free (t);
 923   return (var == 0 || invisible_p (var)) ? (SHELL_VAR *)0 : var;
 924 }
 925
 926 #define INDEX_ERROR() \
 927   do \
 928     { \
 929       if (var) \
 930         err_badarraysub (var->name); \
 931       else \
 932         { \
 933           t[-1] = '\0'; \
 934           err_badarraysub (s); \
 935           t[-1] = '[';  /* ] */\
 936         } \
 937       return ((char *)NULL); \
 938     } \
 939   while (0)
 940
 941 /* Return a string containing the elements in the array and subscript
 942    described by S.  If the subscript is * or @, obeys quoting rules akin
 943    to the expansion of $* and $@ including double quoting.  If RTYPE
 944    is non-null it gets 1 if the array reference is name[*], 2 if the
 945    reference is name[@], and 0 otherwise. */
 946 static char *
 947 array_value_internal (s, quoted, flags, rtype, indp)
 948      char *s;
 949      int quoted, flags, *rtype;
 950      arrayind_t *indp;
 951 {
 952   int len;
 953   arrayind_t ind;
 954   char *akey;
 955   char *retval, *t, *temp;
 956   WORD_LIST *l;
 957   SHELL_VAR *var;
 958
 959   var = array_variable_part (s, &t, &len);
 960
 961   /* Expand the index, even if the variable doesn't exist, in case side
 962      effects are needed, like ${w[i++]} where w is unset. */
 963 #if 0
 964   if (var == 0)
 965     return (char *)NULL;
 966 #endif
 967
 968   if (len == 0)
 969     return ((char *)NULL);      /* error message already printed */
 970
 971   /* [ */
 972   akey = 0;
 973   if (ALL_ELEMENT_SUB (t[0]) && t[1] == ']')
 974     {
 975       if (rtype)
 976         *rtype = (t[0] == '*') ? 1 : 2;
 977       if ((flags & AV_ALLOWALL) == 0)
 978         {
 979           err_badarraysub (s);
 980           return ((char *)NULL);
 981         }
 982       else if (var == 0 || value_cell (var) == 0)       /* XXX - check for invisible_p(var) ? */
 983         return ((char *)NULL);
 984       else if (array_p (var) == 0 && assoc_p (var) == 0)
 985         l = add_string_to_list (value_cell (var), (WORD_LIST *)NULL);
 986       else if (assoc_p (var))
 987         {
 988           l = assoc_to_word_list (assoc_cell (var));
 989           if (l == (WORD_LIST *)NULL)
 990             return ((char *)NULL);
 991         }
 992       else
 993         {
 994           l = array_to_word_list (array_cell (var));
 995           if (l == (WORD_LIST *)NULL)
 996             return ((char *) NULL);
 997         }
 998
 999       if (t[0] == '*' && (quoted & (Q_HERE_DOCUMENT|Q_DOUBLE_QUOTES)))
1000         {
1001           temp = string_list_dollar_star (l);
1002           retval = quote_string (temp);         /* XXX - leak here */
1003           free (temp);
1004         }
1005       else      /* ${name[@]} or unquoted ${name[*]} */
1006         retval = string_list_dollar_at (l, quoted);     /* XXX - leak here */
1007
1008       dispose_words (l);
1009     }
1010   else
1011     {
1012       if (rtype)
1013         *rtype = 0;
1014       if (var == 0 || array_p (var) || assoc_p (var) == 0)
1015         {
1016           if ((flags & AV_USEIND) == 0 || indp == 0)
1017             {
1018               ind = array_expand_index (var, t, len);
1019               if (ind < 0)
1020                 {
1021                   /* negative subscripts to indexed arrays count back from end */
1022                   if (var && array_p (var))
1023                     ind = array_max_index (array_cell (var)) + 1 + ind;
1024                   if (ind < 0)
1025                     INDEX_ERROR();
1026                 }
1027               if (indp)
1028                 *indp = ind;
1029             }
1030           else if (indp)
1031             ind = *indp;
1032         }
1033       else if (assoc_p (var))
1034         {
1035           t[len - 1] = '\0';
1036           akey = expand_assignment_string_to_string (t, 0);     /* [ */
1037           t[len - 1] = ']';
1038           if (akey == 0 || *akey == 0)
1039             {
1040               FREE (akey);
1041               INDEX_ERROR();
1042             }
1043         }
1044
1045       if (var == 0 || value_cell (var) == 0)    /* XXX - check invisible_p(var) ? */
1046         {
1047           FREE (akey);
1048           return ((char *)NULL);
1049         }
1050       if (array_p (var) == 0 && assoc_p (var) == 0)
1051         return (ind == 0 ? value_cell (var) : (char *)NULL);
1052       else if (assoc_p (var))
1053         {
1054           retval = assoc_reference (assoc_cell (var), akey);
1055           free (akey);
1056         }
1057       else
1058         retval = array_reference (array_cell (var), ind);
1059     }
1060
1061   return retval;
1062 }
1063
1064 /* Return a string containing the elements described by the array and
1065    subscript contained in S, obeying quoting for subscripts * and @. */
1066 char *
1067 array_value (s, quoted, flags, rtype, indp)
1068      char *s;
1069      int quoted, flags, *rtype;
1070      arrayind_t *indp;
1071 {
1072   return (array_value_internal (s, quoted, flags|AV_ALLOWALL, rtype, indp));
1073 }
1074
1075 /* Return the value of the array indexing expression S as a single string.
1076    If (FLAGS & AV_ALLOWALL) is 0, do not allow `@' and `*' subscripts.  This
1077    is used by other parts of the shell such as the arithmetic expression
1078    evaluator in expr.c. */
1079 char *
1080 get_array_value (s, flags, rtype, indp)
1081      char *s;
1082      int flags, *rtype;
1083      arrayind_t *indp;
1084 {
1085   return (array_value_internal (s, 0, flags, rtype, indp));
1086 }
1087
1088 char *
1089 array_keys (s, quoted)
1090      char *s;
1091      int quoted;
1092 {
1093   int len;
1094   char *retval, *t, *temp;
1095   WORD_LIST *l;
1096   SHELL_VAR *var;
1097
1098   var = array_variable_part (s, &t, &len);
1099
1100   /* [ */
1101   if (var == 0 || ALL_ELEMENT_SUB (t[0]) == 0 || t[1] != ']')
1102     return (char *)NULL;
1103
1104   if (var_isset (var) == 0 || invisible_p (var))
1105     return (char *)NULL;
1106
1107   if (array_p (var) == 0 && assoc_p (var) == 0)
1108     l = add_string_to_list ("0", (WORD_LIST *)NULL);
1109   else if (assoc_p (var))
1110     l = assoc_keys_to_word_list (assoc_cell (var));
1111   else
1112     l = array_keys_to_word_list (array_cell (var));
1113   if (l == (WORD_LIST *)NULL)
1114     return ((char *) NULL);
1115
1116   if (t[0] == '*' && (quoted & (Q_HERE_DOCUMENT|Q_DOUBLE_QUOTES)))
1117     {
1118       temp = string_list_dollar_star (l);
1119       retval = quote_string (temp);
1120       free (temp);
1121     }
1122   else  /* ${!name[@]} or unquoted ${!name[*]} */
1123     retval = string_list_dollar_at (l, quoted);
1124
1125   dispose_words (l);
1126   return retval;
1127 }
1128 #endif /* ARRAY_VARS */