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