src/compile.c

   1 /*
   2  * Copyright 1993-2002 Christopher Seiwald and Perforce Software, Inc.
   3  *
   4  * This file is part of Jam - see jam.c for Copyright information.
   5  */
   6 /*
   7  * compile.c - compile parsed jam statements
   8  *
   9  * External routines:
  10  *
  11  *  compile_append() - append list results of two statements
  12  *  compile_break() - compile 'break/continue/return' rule
  13  *  compile_eval() - evaluate if to determine which leg to compile
  14  *  compile_foreach() - compile the "for x in y" statement
  15  *  compile_if() - compile 'if' rule
  16  *  compile_include() - support for 'include' - call include() on file
  17  *  compile_list() - expand and return a list
  18  *  compile_local() - declare (and set) local variables
  19  *  compile_null() - do nothing -- a stub for parsing
  20  *  compile_on() - run rule under influence of on-target variables
  21  *  compile_rule() - compile a single user defined rule
  22  *  compile_rules() - compile a chain of rules
  23  *  compile_set() - compile the "set variable" statement
  24  *  compile_setcomp() - support for `rule` - save parse tree
  25  *  compile_setexec() - support for `actions` - save execution string
  26  *  compile_settings() - compile the "on =" (set variable on exec) statement
  27  *  compile_switch() - compile 'switch' rule
  28  *
  29  * Internal routines:
  30  *
  31  *  debug_compile() - printf with indent to show rule expansion.
  32  *  evaluate_rule() - execute a rule invocation
  33  *
  34  * 02/03/94 (seiwald) - Changed trace output to read "setting" instead of
  35  *      the awkward sounding "settings".
  36  * 04/12/94 (seiwald) - Combined build_depends() with build_includes().
  37  * 04/12/94 (seiwald) - actionlist() now just appends a single action.
  38  * 04/13/94 (seiwald) - added shorthand L0 for null list pointer
  39  * 05/13/94 (seiwald) - include files are now bound as targets, and thus
  40  *      can make use of $(SEARCH)
  41  * 06/01/94 (seiwald) - new 'actions existing' does existing sources
  42  * 08/23/94 (seiwald) - Support for '+=' (append to variable)
  43  * 12/20/94 (seiwald) - NOTIME renamed NOTFILE.
  44  * 01/22/95 (seiwald) - Exit rule.
  45  * 02/02/95 (seiwald) - Always rule; LEAVES rule.
  46  * 02/14/95 (seiwald) - NoUpdate rule.
  47  * 01/20/00 (seiwald) - Upgraded from K&R to ANSI C
  48  * 09/07/00 (seiwald) - stop crashing when a rule redefines itself
  49  * 09/11/00 (seiwald) - new evaluate_rule() for headers().
  50  * 09/11/00 (seiwald) - rules now return values, accessed via [ rule arg ... ]
  51  * 09/12/00 (seiwald) - don't complain about rules invoked without targets
  52  * 01/13/01 (seiwald) - fix case where rule is defined within another
  53  * 01/10/01 (seiwald) - built-ins split out to builtin.c.
  54  * 01/11/01 (seiwald) - optimize compile_rules() for tail recursion
  55  * 01/21/01 (seiwald) - replace evaluate_if() with compile_eval()
  56  * 01/24/01 (seiwald) - 'while' statement
  57  * 03/23/01 (seiwald) - "[ on target rule ]" support
  58  * 02/28/02 (seiwald) - merge EXEC_xxx flags in with RULE_xxx
  59  * 03/02/02 (seiwald) - rules can be invoked via variable names
  60  * 03/12/02 (seiwald) - &&,&,||,|,in now short-circuit again
  61  * 03/25/02 (seiwald) - if ( "" a b ) one again returns true
  62  * 06/21/02 (seiwald) - support for named parameters
  63  * 10/22/02 (seiwald) - list_new() now does its own newstr()/copystr()
  64  * 10/22/02 (seiwald) - working return/break/continue statements
  65  * 11/04/02 (seiwald) - const-ing for string literals
  66  * 11/18/02 (seiwald) - remove bogus search() in 'on' statement.
  67  * 12/17/02 (seiwald) - new copysettings() to protect target-specific vars
  68  */
  69 #include "jam.h"
  70
  71 #include "lists.h"
  72 #include "parse.h"
  73 #include "compile.h"
  74 #include "variable.h"
  75 #include "expand.h"
  76 #include "rules.h"
  77 #include "newstr.h"
  78 #include "search.h"
  79 #include "matchglob.h"
  80
  81
  82 static const char *set_names[] = { "=", "+=", "-=", "?=" };
  83 static void debug_compile (int which, const char *s);
  84
  85
  86 /*
  87  * compile_append() - append list results of two statements
  88  *
  89  *  parse->left   more compile_append() by left-recursion
  90  *  parse->right  single rule
  91  */
  92 LIST *compile_append (PARSE *parse, LOL *args, int *jmp) {
  93   /* Append right to left. */
  94   return list_append(
  95     (*parse->left->func)(parse->left, args, jmp),
  96     (*parse->right->func)(parse->right, args, jmp)
  97   );
  98 }
  99
 100
 101 /*
 102  * compile_break() - compile 'break/continue/return' rule
 103  *
 104  *  parse->left  results
 105  *  parse->num   JMP_BREAK/CONTINUE/RETURN
 106  */
 107 LIST *compile_break (PARSE *parse, LOL *args, int *jmp) {
 108   LIST *lv = (*parse->left->func)(parse->left, args, jmp);
 109   *jmp = parse->num;
 110   return lv;
 111 }
 112
 113
 114 /*
 115  * compile_eval() - evaluate if to determine which leg to compile
 116  *
 117  * Returns:
 118  *  list  if expression true - compile 'then' clause
 119  *  L0    if expression false - compile 'else' clause
 120  */
 121 static JAMFA_PURE int lcmp (LIST *t, LIST *s) {
 122   int status = 0;
 123   //
 124   while (!status && (t || s)) {
 125     const char *st = t?t->string:"";
 126     const char *ss = s?s->string:"";
 127     //
 128     status = strcmp(st, ss);
 129     t = t?list_next(t):t;
 130     s = s?list_next(s):s;
 131   }
 132   return status;
 133 }
 134
 135
 136 LIST *compile_eval (PARSE *parse, LOL *args, int *jmp) {
 137   LIST *ll, *lr, *s, *t;
 138   int status = 0;
 139   //
 140   /* short circuit lr eval for &&, ||, and 'in' */
 141   ll = (*parse->left->func)(parse->left, args, jmp);
 142   lr = 0;
 143   switch (parse->num) {
 144     case EXPR_AND:
 145     case EXPR_IN:
 146     case EXPR_ANYIN:
 147       if (ll) goto eval;
 148       break;
 149     case EXPR_OR:
 150       if (!ll) goto eval;
 151       break;
 152     default:
 153 eval: lr = (*parse->right->func)(parse->right, args, jmp);
 154       break;
 155   }
 156   /* now eval */
 157   switch (parse->num) {
 158     case EXPR_NOT:
 159       if (!ll) status = 1;
 160       break;
 161     case EXPR_AND:
 162       if (ll && lr) status = 1;
 163       break;
 164     case EXPR_OR:
 165       if (ll || lr) status = 1;
 166       break;
 167     case EXPR_IN:
 168       /* "a in b": make sure each of ll is equal to something in lr */
 169       for (t = ll; t; t = list_next(t)) {
 170         for (s = lr; s; s = list_next(s)) if (strcmp(t->string, s->string) == 0) break;
 171         if (!s) break;
 172       }
 173       /* No more ll? success */
 174       if (!t) status = 1;
 175       break;
 176     case EXPR_ANYIN:
 177       /* "a any-in b": does b contains at least one item from a? */
 178       for (t = ll; t && !status; t = list_next(t)) {
 179         for (s = lr; s; s = list_next(s)) if (strcmp(t->string, s->string) == 0) { status = 1; break; } /* success */
 180       }
 181       break;
 182     case EXPR_EXISTS:
 183       if (lcmp(ll, L0) != 0) status = 1;
 184       break;
 185     case EXPR_EQUALS:
 186       if (lcmp(ll, lr) == 0) status = 1;
 187       break;
 188     case EXPR_NOTEQ:
 189       if (lcmp(ll, lr) != 0) status = 1;
 190       break;
 191     case EXPR_LESS:
 192       if (lcmp(ll, lr) < 0) status = 1;
 193       break;
 194     case EXPR_LESSEQ:
 195       if (lcmp(ll, lr) <= 0) status = 1;
 196       break;
 197     case EXPR_MORE:
 198       if (lcmp(ll, lr) > 0) status = 1;
 199       break;
 200     case EXPR_MOREEQ:
 201       if (lcmp(ll, lr) >= 0) status = 1;
 202       break;
 203   }
 204   if (DEBUG_IF) {
 205     debug_compile(0, "if");
 206     list_print(ll);
 207     printf("(%d) ", status);
 208     list_print(lr);
 209     printf("\n");
 210   }
 211   /* find something to return */
 212   /* in odd circumstances (like "" = "") we'll have to return a new string */
 213   if (!status) t = 0;
 214   else if (ll) t = ll, ll = 0;
 215   else if (lr) t = lr, lr = 0;
 216   else t = list_new(L0, "1", 0);
 217   if (ll) list_free(ll);
 218   if (lr) list_free(lr);
 219   return t;
 220 }
 221
 222
 223 /*
 224  * compile_foreach() - compile the "for x in y" statement
 225  *
 226  * Compile_foreach() resets the given variable name to each specified
 227  * value, executing the commands enclosed in braces for each iteration.
 228  *
 229  *  parse->string  index variable
 230  *  parse->left    variable values
 231  *  parse->right   rule to compile
 232  */
 233 LIST *compile_foreach (PARSE *p, LOL *args, int *jmp) {
 234   LIST *nv = (*p->left->func)(p->left, args, jmp);
 235   LIST *result = 0;
 236   LIST *l;
 237   //
 238   /* for each value for var */
 239   for (l = nv; l && *jmp == JMP_NONE; l = list_next(l)) {
 240     /* reset $(p->string) for each val */
 241     var_set(p->string, list_new(L0, l->string, 1), VAR_SET);
 242     /* keep only last result */
 243     list_free(result);
 244     result = (*p->right->func)(p->right, args, jmp);
 245     /* continue loop? */
 246     if (*jmp == JMP_CONTINUE) *jmp = JMP_NONE;
 247   }
 248   /* here by break/continue? */
 249   if (*jmp == JMP_BREAK || *jmp == JMP_CONTINUE) *jmp = JMP_NONE;
 250   list_free(nv);
 251   /* returns result of last loop */
 252   return result;
 253 }
 254
 255
 256 /*
 257  * compile_if() - compile 'if' rule
 258  *
 259  *  parse->left   condition tree
 260  *  parse->right  then tree
 261  *  parse->third  else tree
 262  */
 263 LIST *compile_if (PARSE *p, LOL *args, int *jmp) {
 264   LIST *l = (*p->left->func)(p->left, args, jmp);
 265   //
 266   p = l?p->right:p->third;
 267   list_free(l);
 268   return (*p->func)(p, args, jmp);
 269 }
 270
 271
 272 /*
 273  * compile_include() - support for 'include' - call include() on file
 274  *
 275  *  parse->left list of files to include (can only do 1)
 276  */
 277 static LIST *compile_include_internal (PARSE *parse, LOL *args, int *jmp, int assoft) {
 278   LIST *nt = (*parse->left->func)(parse->left, args, jmp);
 279   //
 280   if (DEBUG_COMPILE) {
 281     debug_compile(0, (assoft?"softinclude":"include"));
 282     list_print(nt);
 283     printf("\n");
 284   }
 285   if (nt) {
 286     TARGET *t = bindtarget(nt->string);
 287     /* bind the include file under the influence of "on-target" variables */
 288     /* though they are targets, include files are not built with make() */
 289     /* needn't copysettings(), as search sets no vars */
 290     pushsettings(t->settings);
 291     t->boundname = search(t->name, &t->time);
 292     popsettings(t->settings);
 293     /* don't parse missing file if NOCARE set */
 294     if (t->time || !(t->flags & T_FLAG_NOCARE)) {
 295       int doit = 1;
 296       FILE *fl = fopen(t->boundname, "r");
 297       //
 298       if (fl == NULL) {
 299         if (assoft) {
 300           doit = 0;
 301         } else {
 302           printf("Failed to include file '%s'\n", t->boundname);
 303           exit(EXITBAD);
 304         }
 305       } else {
 306         fclose(fl);
 307       }
 308       if (doit) parse_file(t->boundname);
 309     }
 310   }
 311   list_free(nt);
 312   return L0;
 313 }
 314
 315
 316 /*
 317  * compile_include() - support for 'include' - call include() on file
 318  *
 319  *  parse->left list of files to include (can only do 1)
 320  */
 321 LIST *compile_include (PARSE *parse, LOL *args, int *jmp) {
 322   return compile_include_internal(parse, args, jmp, 0);
 323 }
 324
 325
 326 /*
 327  * compile_softinclude() - support for 'softinclude' - call include() on file if file exists
 328  *
 329  *  parse->left list of files to include (can only do 1)
 330  */
 331 LIST *compile_softinclude (PARSE *parse, LOL *args, int *jmp) {
 332   return compile_include_internal(parse, args, jmp, 1);
 333 }
 334
 335
 336 /*
 337  * compile_list() - expand and return a list
 338  *
 339  *  parse->string - character string to expand
 340  */
 341 LIST *compile_list (PARSE *parse, LOL *args, int *jmp) {
 342   /* voodoo 1 means: s is a copyable string */
 343   const char *s = parse->string;
 344   return var_expand(L0, s, s+strlen(s), args, 1);
 345 }
 346
 347
 348 /*
 349  * compile_local() - declare (and set) local variables
 350  *
 351  *  parse->left   list of variables
 352  *  parse->right  list of values
 353  *  parse->third  rules to execute
 354  */
 355 LIST *compile_local (PARSE *parse, LOL *args, int *jmp) {
 356   LIST *l;
 357   SETTINGS *s = 0;
 358   LIST *nt = (*parse->left->func)(parse->left, args, jmp);
 359   LIST *ns = (*parse->right->func)(parse->right, args, jmp);
 360   LIST *result;
 361   //
 362   if (DEBUG_COMPILE) {
 363     debug_compile(0, "local");
 364     list_print(nt);
 365     printf(" = ");
 366     list_print(ns);
 367     printf("\n");
 368   }
 369   /* initial value is ns */
 370   for (l = nt; l; l = list_next(l)) s = addsettings(s, 0, l->string, list_copy((LIST *)0, ns));
 371   list_free(ns);
 372   list_free(nt);
 373   /* note that callees of the current context get this "local" */
 374   /* variable, making it not so much local as layered */
 375   pushsettings(s);
 376   result = (*parse->third->func)(parse->third, args, jmp);
 377   popsettings(s);
 378   freesettings(s);
 379   return result;
 380 }
 381
 382
 383 /*
 384  * compile_null() - do nothing -- a stub for parsing
 385  */
 386 LIST *compile_null (PARSE *parse, LOL *args, int *jmp) {
 387   return L0;
 388 }
 389
 390
 391 /*
 392  * compile_on() - run rule under influence of on-target variables
 393  *
 394  *  parse->left target list; only first used
 395  *  parse->right  rule to run
 396  */
 397 LIST *compile_on (PARSE *parse, LOL *args, int *jmp) {
 398   LIST *nt = (*parse->left->func)(parse->left, args, jmp);
 399   LIST *result = 0;
 400   //
 401   if (DEBUG_COMPILE) {
 402     debug_compile(0, "on");
 403     list_print(nt);
 404     printf("\n");
 405   }
 406   /* copy settings, so that 'on target var on target = val' doesn't set var globally */
 407   if (nt) {
 408     TARGET *t = bindtarget(nt->string);
 409     SETTINGS *s = copysettings(t->settings);
 410     //
 411     pushsettings(s);
 412     result = (*parse->right->func)(parse->right, args, jmp);
 413     popsettings(s);
 414     freesettings(s);
 415   }
 416   list_free(nt);
 417   return result;
 418 }
 419
 420
 421 /*
 422  * compile_rule() - compile a single user defined rule
 423  *
 424  *  parse->left list of rules to run
 425  *  parse->right  parameters (list of lists) to rule, recursing left
 426  *
 427  * Wrapped around evaluate_rule() so that headers() can share it.
 428  */
 429 LIST *compile_rule (PARSE *parse, LOL *args, int *jmp) {
 430   LOL nargs[1];
 431   LIST *result = 0;
 432   LIST *ll, *l;
 433   PARSE *p;
 434   //
 435   /* list of rules to run -- normally 1! */
 436   ll = (*parse->left->func)(parse->left, args, jmp);
 437   /* build up the list of arg lists */
 438   lol_init(nargs);
 439   for (p = parse->right; p; p = p->left) lol_add(nargs, (*p->right->func)(p->right, args, jmp));
 440   /* run rules, appending results from each */
 441   for (l = ll; l; l = list_next(l)) result = evaluate_rule(l->string, nargs, result);
 442   list_free(ll);
 443   lol_free(nargs);
 444   return result;
 445 }
 446
 447
 448 /*
 449  * evaluate_rule() - execute a rule invocation
 450  */
 451 LIST *evaluate_rule (const char *rulename, LOL *args, LIST  *result) {
 452 //#ifdef OPT_EXPAND_RULE_NAMES_EXT
 453   RULE *rule;
 454   char *expanded, *c;
 455   tKString buf;
 456   //
 457   kStringNew(&buf);
 458   if (var_string(rulename, &buf, args, ' ') < 0) {
 459     kStringFree(&buf);
 460     printf("Failed to expand rule %s -- expansion too long\n", rulename);
 461     exit(EXITBAD);
 462   }
 463   expanded = kStringCStr(&buf);
 464   while (expanded[0] == ' ') ++expanded;
 465   while ((c = strrchr(expanded, ' '))) *c = '\0';
 466   if (DEBUG_COMPILE) {
 467     debug_compile(1, rulename);
 468     if (strcmp(rulename, expanded)) printf("-> %s  ", expanded);
 469     lol_print(args);
 470     printf("\n");
 471   }
 472   rule = bindrule(expanded);
 473   kStringFree(&buf);
 474 //#else
 475 /*
 476   RULE *rule = bindrule(rulename);
 477   //
 478   if (DEBUG_COMPILE) {
 479     debug_compile(1, rulename);
 480     lol_print(args);
 481     printf("\n");
 482   }
 483 */
 484 //#endif
 485   /* check traditional targets $(<) and sources $(>) */
 486   if (!rule->actions && !rule->procedure) printf("warning: unknown rule %s\n", rule->name);
 487   /* if this rule will be executed for updating the targets then construct the action for make() */
 488   if (rule->actions) {
 489     TARGETS *t;
 490     ACTION *action;
 491     //
 492     /* the action is associated with this instance of this rule */
 493     action = (ACTION *)malloc(sizeof(ACTION));
 494     memset((char *)action, '\0', sizeof(*action));
 495     action->rule = rule;
 496     action->targets = targetlist((TARGETS *)0, lol_get(args, 0));
 497     action->sources = targetlist((TARGETS *)0, lol_get(args, 1));
 498     /* append this action to the actions of each target */
 499     for (t = action->targets; t; t = t->next) t->target->actions = actionlist(t->target->actions, action);
 500   }
 501   /* now recursively compile any parse tree associated with this rule */
 502   if (rule->procedure) {
 503     PARSE *parse = rule->procedure;
 504     SETTINGS *s = 0;
 505     int jmp = JMP_NONE;
 506     LIST *l;
 507     int i;
 508     //
 509     /* build parameters as local vars */
 510     for (l = rule->params, i = 0; l; l = l->next, i++) s = addsettings(s, 0, l->string, list_copy(L0, lol_get(args, i)));
 511     /* run rule */
 512     /* bring in local params */
 513     /* refer/free to ensure rule not freed during use */
 514     parse_refer(parse);
 515     pushsettings(s);
 516     result = list_append(result, (*parse->func)(parse, args, &jmp));
 517     popsettings(s);
 518     freesettings(s);
 519     parse_free(parse);
 520   }
 521   if (DEBUG_COMPILE) debug_compile(-1, 0);
 522 //#ifdef OPT_EXPAND_RULE_NAMES_EXT
 523   kStringFree(&buf);
 524 //#endif
 525   return result;
 526 }
 527
 528
 529 /*
 530  * compile_rules() - compile a chain of rules
 531  *
 532  *  parse->left single rule
 533  *  parse->right  more compile_rules() by right-recursion
 534  */
 535 LIST *compile_rules (PARSE *parse, LOL *args, int *jmp) {
 536   /* ignore result from first statement; return the 2nd */
 537   /* optimize recursion on the right by looping */
 538   LIST *result = 0;
 539   //
 540   while (*jmp == JMP_NONE && parse->func == compile_rules) {
 541     list_free(result);
 542     result = (*parse->left->func)(parse->left, args, jmp);
 543     parse = parse->right;
 544   }
 545   if (*jmp == JMP_NONE) {
 546     list_free(result);
 547     result = (*parse->func)(parse, args, jmp);
 548   }
 549   return result;
 550 }
 551
 552
 553 /*
 554  * compile_set() - compile the "set variable" statement
 555  *
 556  *  parse->left   variable names
 557  *  parse->right  variable values
 558  *  parse->num    VAR_SET/APPEND/DEFAULT
 559  */
 560 LIST *compile_set (PARSE *parse, LOL *args, int *jmp) {
 561   LIST *nt = (*parse->left->func)(parse->left, args, jmp);
 562   LIST *ns = (*parse->right->func)(parse->right, args, jmp);
 563   LIST *l;
 564   //
 565   if (DEBUG_COMPILE) {
 566     debug_compile(0, "set");
 567     list_print(nt);
 568     printf(" %s ", set_names[parse->num]);
 569     list_print(ns);
 570     printf("\n");
 571   }
 572   /* call var_set to set variable */
 573   /* var_set keeps ns, so need to copy it */
 574   for (l = nt; l; l = list_next(l)) var_set(l->string, list_copy(L0, ns), parse->num);
 575   list_free(nt);
 576   return ns;
 577 }
 578
 579
 580 /*
 581  * compile_setcomp() - support for `rule` - save parse tree
 582  *
 583  *  parse->string  rule name
 584  *  parse->left    list of argument names
 585  *  parse->right   rules for rule
 586  */
 587 LIST *compile_setcomp (PARSE *parse, LOL *args, int *jmp) {
 588   RULE *rule = bindrule(parse->string);
 589   LIST *params = 0;
 590   PARSE *p;
 591   //
 592   /* build param list */
 593   for (p = parse->left; p; p = p->left) params = list_new(params, p->string, 1);
 594   if (DEBUG_COMPILE) {
 595     debug_compile(0, "rule");
 596     printf("%s ", parse->string);
 597     list_print(params);
 598     printf("\n");
 599   }
 600   /* free old one, if present */
 601   if (rule->procedure) parse_free(rule->procedure);
 602   if (rule->params) list_free(rule->params);
 603   rule->procedure = parse->right;
 604   rule->params = params;
 605   /* we now own this parse tree */
 606   /* don't let parse_free() release it */
 607   parse_refer(parse->right);
 608   return L0;
 609 }
 610
 611
 612 /*
 613  * compile_setexec() - support for `actions` - save execution string
 614  *
 615  *  parse->string   rule name
 616  *  parse->string1  OS command string
 617  *  parse->num      flags
 618  *  parse->left     `bind` variables
 619  *
 620  * Note that the parse flags (as defined in compile.h) are transfered
 621  * directly to the rule flags (as defined in rules.h).
 622  */
 623 LIST *compile_setexec (PARSE *parse, LOL *args, int *jmp) {
 624   RULE *rule = bindrule(parse->string);
 625   LIST *bindlist = (*parse->left->func)(parse->left, args, jmp);
 626   //
 627   /* free old one, if present */
 628   if (rule->actions) {
 629     freestr(rule->actions);
 630     list_free(rule->bindlist);
 631   }
 632   rule->actions = copystr(parse->string1);
 633   rule->bindlist = bindlist;
 634   rule->flags = parse->num;
 635   return L0;
 636 }
 637
 638
 639 /*
 640  * compile_settings() - compile the "on =" (set variable on exec) statement
 641  *
 642  *  parse->left   variable names
 643  *  parse->right  target name
 644  *  parse->third  variable value
 645  *  parse->num    VAR_SET/APPEND/DEFAULT
 646  */
 647 LIST *compile_settings (PARSE *parse, LOL *args, int *jmp) {
 648   LIST *nt = (*parse->left->func)(parse->left, args, jmp);
 649   LIST *ns = (*parse->third->func)(parse->third, args, jmp);
 650   LIST *targets = (*parse->right->func)(parse->right, args, jmp);
 651   LIST *ts;
 652   //
 653   if (DEBUG_COMPILE) {
 654     debug_compile(0, "set");
 655     list_print(nt);
 656     printf("on ");
 657     list_print(targets);
 658     printf(" %s ", set_names[parse->num]);
 659     list_print(ns);
 660     printf("\n");
 661   }
 662   /* call addsettings to save variable setting addsettings keeps ns, so need to copy it */
 663   /* pass append flag to addsettings() */
 664   for (ts = targets; ts; ts = list_next(ts)) {
 665     TARGET *t = bindtarget(ts->string);
 666     LIST *l;
 667     //
 668     for (l = nt; l; l = list_next(l)) {
 669       t->settings = addsettings(t->settings, parse->num, l->string, list_copy((LIST *)0, ns));
 670     }
 671   }
 672   list_free(nt);
 673   list_free(targets);
 674   return ns;
 675 }
 676
 677
 678 /*
 679  * compile_switch() - compile 'switch' rule
 680  *
 681  *  parse->left   switch value (only 1st used)
 682  *  parse->right  cases
 683  *
 684  *  cases->left   1st case
 685  *  cases->right  next cases
 686  *
 687  *  case->string  argument to match
 688  *  case->left    parse tree to execute
 689  */
 690 LIST *compile_switch (PARSE *parse, LOL *args, int *jmp) {
 691   LIST *nt = (*parse->left->func)(parse->left, args, jmp);
 692   LIST *result = 0;
 693   //
 694   if (DEBUG_COMPILE) {
 695     debug_compile(0, "switch");
 696     list_print(nt);
 697     printf("\n");
 698   }
 699   /* step through cases */
 700   for (parse = parse->right; parse; parse = parse->right) {
 701     if (!matchglob(parse->left->string, nt?nt->string:"")) {
 702       /* get and exec parse tree for this case */
 703       parse = parse->left->left;
 704       result = (*parse->func)(parse, args, jmp);
 705       break;
 706     }
 707   }
 708   list_free(nt);
 709   return result;
 710 }
 711
 712
 713 /*
 714  * compile_while() - compile 'while' rule
 715  *
 716  *  parse->left   condition tree
 717  *  parse->right    execution tree
 718  */
 719 LIST *compile_while (PARSE *p, LOL *args, int *jmp) {
 720   LIST *result = 0;
 721   LIST *l;
 722   //
 723   /* returns the value from the last execution of the block */
 724   while ((*jmp == JMP_NONE ) && (l = (*p->left->func)(p->left, args, jmp))) {
 725     /* always toss while's expression */
 726     list_free(l);
 727     /* keep only last result */
 728     list_free(result);
 729     result = (*p->right->func)(p->right, args, jmp);
 730     /* continue loop? */
 731     if (*jmp == JMP_CONTINUE) *jmp = JMP_NONE;
 732   }
 733   /* here by break/continue? */
 734   if (*jmp == JMP_BREAK || *jmp == JMP_CONTINUE) *jmp = JMP_NONE;
 735   /* returns result of last loop */
 736   return result;
 737 }
 738
 739
 740 /*
 741  * debug_compile() - printf with indent to show rule expansion.
 742  */
 743 static void debug_compile (int which, const char *s) {
 744   static int level = 0;
 745   static const char indent[36] = ">>>>|>>>>|>>>>|>>>>|>>>>|>>>>|>>>>|";
 746   int i = ((1+level)*2)%35;
 747   //
 748   if (which >= 0) printf("%*.*s ", i, i, indent);
 749   if (s) printf("%s ", s);
 750   level += which;
 751 }