cond.c revision 1.68 1 /* $NetBSD: cond.c,v 1.68 2015/05/05 21:51:09 sjg Exp $ */
2
3 /*
4 * Copyright (c) 1988, 1989, 1990 The Regents of the University of California.
5 * All rights reserved.
6 *
7 * This code is derived from software contributed to Berkeley by
8 * Adam de Boor.
9 *
10 * Redistribution and use in source and binary forms, with or without
11 * modification, are permitted provided that the following conditions
12 * are met:
13 * 1. Redistributions of source code must retain the above copyright
14 * notice, this list of conditions and the following disclaimer.
15 * 2. Redistributions in binary form must reproduce the above copyright
16 * notice, this list of conditions and the following disclaimer in the
17 * documentation and/or other materials provided with the distribution.
18 * 3. Neither the name of the University nor the names of its contributors
19 * may be used to endorse or promote products derived from this software
20 * without specific prior written permission.
21 *
22 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
23 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
24 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
25 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
26 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
27 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
28 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
29 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
30 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
31 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
32 * SUCH DAMAGE.
33 */
34
35 /*
36 * Copyright (c) 1988, 1989 by Adam de Boor
37 * Copyright (c) 1989 by Berkeley Softworks
38 * All rights reserved.
39 *
40 * This code is derived from software contributed to Berkeley by
41 * Adam de Boor.
42 *
43 * Redistribution and use in source and binary forms, with or without
44 * modification, are permitted provided that the following conditions
45 * are met:
46 * 1. Redistributions of source code must retain the above copyright
47 * notice, this list of conditions and the following disclaimer.
48 * 2. Redistributions in binary form must reproduce the above copyright
49 * notice, this list of conditions and the following disclaimer in the
50 * documentation and/or other materials provided with the distribution.
51 * 3. All advertising materials mentioning features or use of this software
52 * must display the following acknowledgement:
53 * This product includes software developed by the University of
54 * California, Berkeley and its contributors.
55 * 4. Neither the name of the University nor the names of its contributors
56 * may be used to endorse or promote products derived from this software
57 * without specific prior written permission.
58 *
59 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
60 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
61 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
62 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
63 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
64 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
65 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
66 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
67 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
68 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
69 * SUCH DAMAGE.
70 */
71
72 #ifndef MAKE_NATIVE
73 static char rcsid[] = "$NetBSD: cond.c,v 1.68 2015/05/05 21:51:09 sjg Exp $";
74 #else
75 #include <sys/cdefs.h>
76 #ifndef lint
77 #if 0
78 static char sccsid[] = "@(#)cond.c 8.2 (Berkeley) 1/2/94";
79 #else
80 __RCSID("$NetBSD: cond.c,v 1.68 2015/05/05 21:51:09 sjg Exp $");
81 #endif
82 #endif /* not lint */
83 #endif
84
85 /*-
86 * cond.c --
87 * Functions to handle conditionals in a makefile.
88 *
89 * Interface:
90 * Cond_Eval Evaluate the conditional in the passed line.
91 *
92 */
93
94 #include <ctype.h>
95 #include <errno.h> /* For strtoul() error checking */
96
97 #include "make.h"
98 #include "hash.h"
99 #include "dir.h"
100 #include "buf.h"
101
102 /*
103 * The parsing of conditional expressions is based on this grammar:
104 * E -> F || E
105 * E -> F
106 * F -> T && F
107 * F -> T
108 * T -> defined(variable)
109 * T -> make(target)
110 * T -> exists(file)
111 * T -> empty(varspec)
112 * T -> target(name)
113 * T -> commands(name)
114 * T -> symbol
115 * T -> $(varspec) op value
116 * T -> $(varspec) == "string"
117 * T -> $(varspec) != "string"
118 * T -> "string"
119 * T -> ( E )
120 * T -> ! T
121 * op -> == | != | > | < | >= | <=
122 *
123 * 'symbol' is some other symbol to which the default function (condDefProc)
124 * is applied.
125 *
126 * Tokens are scanned from the 'condExpr' string. The scanner (CondToken)
127 * will return TOK_AND for '&' and '&&', TOK_OR for '|' and '||',
128 * TOK_NOT for '!', TOK_LPAREN for '(', TOK_RPAREN for ')' and will evaluate
129 * the other terminal symbols, using either the default function or the
130 * function given in the terminal, and return the result as either TOK_TRUE
131 * or TOK_FALSE.
132 *
133 * TOK_FALSE is 0 and TOK_TRUE 1 so we can directly assign C comparisons.
134 *
135 * All Non-Terminal functions (CondE, CondF and CondT) return TOK_ERROR on
136 * error.
137 */
138 typedef enum {
139 TOK_FALSE = 0, TOK_TRUE = 1, TOK_AND, TOK_OR, TOK_NOT,
140 TOK_LPAREN, TOK_RPAREN, TOK_EOF, TOK_NONE, TOK_ERROR
141 } Token;
142
143 /*-
144 * Structures to handle elegantly the different forms of #if's. The
145 * last two fields are stored in condInvert and condDefProc, respectively.
146 */
147 static void CondPushBack(Token);
148 static int CondGetArg(char **, char **, const char *);
149 static Boolean CondDoDefined(int, const char *);
150 static int CondStrMatch(const void *, const void *);
151 static Boolean CondDoMake(int, const char *);
152 static Boolean CondDoExists(int, const char *);
153 static Boolean CondDoTarget(int, const char *);
154 static Boolean CondDoCommands(int, const char *);
155 static Boolean CondCvtArg(char *, double *);
156 static Token CondToken(Boolean);
157 static Token CondT(Boolean);
158 static Token CondF(Boolean);
159 static Token CondE(Boolean);
160 static int do_Cond_EvalExpression(Boolean *);
161
162 static const struct If {
163 const char *form; /* Form of if */
164 int formlen; /* Length of form */
165 Boolean doNot; /* TRUE if default function should be negated */
166 Boolean (*defProc)(int, const char *); /* Default function to apply */
167 } ifs[] = {
168 { "def", 3, FALSE, CondDoDefined },
169 { "ndef", 4, TRUE, CondDoDefined },
170 { "make", 4, FALSE, CondDoMake },
171 { "nmake", 5, TRUE, CondDoMake },
172 { "", 0, FALSE, CondDoDefined },
173 { NULL, 0, FALSE, NULL }
174 };
175
176 static const struct If *if_info; /* Info for current statement */
177 static char *condExpr; /* The expression to parse */
178 static Token condPushBack=TOK_NONE; /* Single push-back token used in
179 * parsing */
180
181 static unsigned int cond_depth = 0; /* current .if nesting level */
182 static unsigned int cond_min_depth = 0; /* depth at makefile open */
183
184 /*
185 * Indicate when we should be strict about lhs of comparisons.
186 * TRUE when Cond_EvalExpression is called from Cond_Eval (.if etc)
187 * FALSE when Cond_EvalExpression is called from var.c:ApplyModifiers
188 * since lhs is already expanded and we cannot tell if
189 * it was a variable reference or not.
190 */
191 static Boolean lhsStrict;
192
193 static int
194 istoken(const char *str, const char *tok, size_t len)
195 {
196 return strncmp(str, tok, len) == 0 && !isalpha((unsigned char)str[len]);
197 }
198
199 /*-
200 *-----------------------------------------------------------------------
201 * CondPushBack --
202 * Push back the most recent token read. We only need one level of
203 * this, so the thing is just stored in 'condPushback'.
204 *
205 * Input:
206 * t Token to push back into the "stream"
207 *
208 * Results:
209 * None.
210 *
211 * Side Effects:
212 * condPushback is overwritten.
213 *
214 *-----------------------------------------------------------------------
215 */
216 static void
217 CondPushBack(Token t)
218 {
219 condPushBack = t;
220 }
221
222 /*-
224 *-----------------------------------------------------------------------
225 * CondGetArg --
226 * Find the argument of a built-in function.
227 *
228 * Input:
229 * parens TRUE if arg should be bounded by parens
230 *
231 * Results:
232 * The length of the argument and the address of the argument.
233 *
234 * Side Effects:
235 * The pointer is set to point to the closing parenthesis of the
236 * function call.
237 *
238 *-----------------------------------------------------------------------
239 */
240 static int
241 CondGetArg(char **linePtr, char **argPtr, const char *func)
242 {
243 char *cp;
244 int argLen;
245 Buffer buf;
246 int paren_depth;
247 char ch;
248
249 cp = *linePtr;
250 if (func != NULL)
251 /* Skip opening '(' - verfied by caller */
252 cp++;
253
254 if (*cp == '\0') {
255 /*
256 * No arguments whatsoever. Because 'make' and 'defined' aren't really
257 * "reserved words", we don't print a message. I think this is better
258 * than hitting the user with a warning message every time s/he uses
259 * the word 'make' or 'defined' at the beginning of a symbol...
260 */
261 *argPtr = NULL;
262 return (0);
263 }
264
265 while (*cp == ' ' || *cp == '\t') {
266 cp++;
267 }
268
269 /*
270 * Create a buffer for the argument and start it out at 16 characters
271 * long. Why 16? Why not?
272 */
273 Buf_Init(&buf, 16);
274
275 paren_depth = 0;
276 for (;;) {
277 ch = *cp;
278 if (ch == 0 || ch == ' ' || ch == '\t')
279 break;
280 if ((ch == '&' || ch == '|') && paren_depth == 0)
281 break;
282 if (*cp == '$') {
283 /*
284 * Parse the variable spec and install it as part of the argument
285 * if it's valid. We tell Var_Parse to complain on an undefined
286 * variable, so we don't do it too. Nor do we return an error,
287 * though perhaps we should...
288 */
289 char *cp2;
290 int len;
291 void *freeIt;
292
293 cp2 = Var_Parse(cp, VAR_CMD, TRUE, &len, &freeIt);
294 Buf_AddBytes(&buf, strlen(cp2), cp2);
295 if (freeIt)
296 free(freeIt);
297 cp += len;
298 continue;
299 }
300 if (ch == '(')
301 paren_depth++;
302 else
303 if (ch == ')' && --paren_depth < 0)
304 break;
305 Buf_AddByte(&buf, *cp);
306 cp++;
307 }
308
309 *argPtr = Buf_GetAll(&buf, &argLen);
310 Buf_Destroy(&buf, FALSE);
311
312 while (*cp == ' ' || *cp == '\t') {
313 cp++;
314 }
315
316 if (func != NULL && *cp++ != ')') {
317 Parse_Error(PARSE_WARNING, "Missing closing parenthesis for %s()",
318 func);
319 return (0);
320 }
321
322 *linePtr = cp;
323 return (argLen);
324 }
325
326 /*-
328 *-----------------------------------------------------------------------
329 * CondDoDefined --
330 * Handle the 'defined' function for conditionals.
331 *
332 * Results:
333 * TRUE if the given variable is defined.
334 *
335 * Side Effects:
336 * None.
337 *
338 *-----------------------------------------------------------------------
339 */
340 static Boolean
341 CondDoDefined(int argLen MAKE_ATTR_UNUSED, const char *arg)
342 {
343 char *p1;
344 Boolean result;
345
346 if (Var_Value(arg, VAR_CMD, &p1) != NULL) {
347 result = TRUE;
348 } else {
349 result = FALSE;
350 }
351 if (p1)
352 free(p1);
353 return (result);
354 }
355
356 /*-
358 *-----------------------------------------------------------------------
359 * CondStrMatch --
360 * Front-end for Str_Match so it returns 0 on match and non-zero
361 * on mismatch. Callback function for CondDoMake via Lst_Find
362 *
363 * Results:
364 * 0 if string matches pattern
365 *
366 * Side Effects:
367 * None
368 *
369 *-----------------------------------------------------------------------
370 */
371 static int
372 CondStrMatch(const void *string, const void *pattern)
373 {
374 return(!Str_Match(string, pattern));
375 }
376
377 /*-
379 *-----------------------------------------------------------------------
380 * CondDoMake --
381 * Handle the 'make' function for conditionals.
382 *
383 * Results:
384 * TRUE if the given target is being made.
385 *
386 * Side Effects:
387 * None.
388 *
389 *-----------------------------------------------------------------------
390 */
391 static Boolean
392 CondDoMake(int argLen MAKE_ATTR_UNUSED, const char *arg)
393 {
394 return Lst_Find(create, arg, CondStrMatch) != NULL;
395 }
396
397 /*-
399 *-----------------------------------------------------------------------
400 * CondDoExists --
401 * See if the given file exists.
402 *
403 * Results:
404 * TRUE if the file exists and FALSE if it does not.
405 *
406 * Side Effects:
407 * None.
408 *
409 *-----------------------------------------------------------------------
410 */
411 static Boolean
412 CondDoExists(int argLen MAKE_ATTR_UNUSED, const char *arg)
413 {
414 Boolean result;
415 char *path;
416
417 path = Dir_FindFile(arg, dirSearchPath);
418 if (DEBUG(COND)) {
419 fprintf(debug_file, "exists(%s) result is \"%s\"\n",
420 arg, path ? path : "");
421 }
422 if (path != NULL) {
423 result = TRUE;
424 free(path);
425 } else {
426 result = FALSE;
427 }
428 return (result);
429 }
430
431 /*-
433 *-----------------------------------------------------------------------
434 * CondDoTarget --
435 * See if the given node exists and is an actual target.
436 *
437 * Results:
438 * TRUE if the node exists as a target and FALSE if it does not.
439 *
440 * Side Effects:
441 * None.
442 *
443 *-----------------------------------------------------------------------
444 */
445 static Boolean
446 CondDoTarget(int argLen MAKE_ATTR_UNUSED, const char *arg)
447 {
448 GNode *gn;
449
450 gn = Targ_FindNode(arg, TARG_NOCREATE);
451 return (gn != NULL) && !OP_NOP(gn->type);
452 }
453
454 /*-
455 *-----------------------------------------------------------------------
456 * CondDoCommands --
457 * See if the given node exists and is an actual target with commands
458 * associated with it.
459 *
460 * Results:
461 * TRUE if the node exists as a target and has commands associated with
462 * it and FALSE if it does not.
463 *
464 * Side Effects:
465 * None.
466 *
467 *-----------------------------------------------------------------------
468 */
469 static Boolean
470 CondDoCommands(int argLen MAKE_ATTR_UNUSED, const char *arg)
471 {
472 GNode *gn;
473
474 gn = Targ_FindNode(arg, TARG_NOCREATE);
475 return (gn != NULL) && !OP_NOP(gn->type) && !Lst_IsEmpty(gn->commands);
476 }
477
478 /*-
480 *-----------------------------------------------------------------------
481 * CondCvtArg --
482 * Convert the given number into a double.
483 * We try a base 10 or 16 integer conversion first, if that fails
484 * then we try a floating point conversion instead.
485 *
486 * Results:
487 * Sets 'value' to double value of string.
488 * Returns 'true' if the convertion suceeded
489 *
490 *-----------------------------------------------------------------------
491 */
492 static Boolean
493 CondCvtArg(char *str, double *value)
494 {
495 char *eptr, ech;
496 unsigned long l_val;
497 double d_val;
498
499 errno = 0;
500 l_val = strtoul(str, &eptr, str[1] == 'x' ? 16 : 10);
501 ech = *eptr;
502 if (ech == 0 && errno != ERANGE) {
503 d_val = str[0] == '-' ? -(double)-l_val : (double)l_val;
504 } else {
505 if (ech != 0 && ech != '.' && ech != 'e' && ech != 'E')
506 return FALSE;
507 d_val = strtod(str, &eptr);
508 if (*eptr)
509 return FALSE;
510 }
511
512 *value = d_val;
513 return TRUE;
514 }
515
516 /*-
517 *-----------------------------------------------------------------------
518 * CondGetString --
519 * Get a string from a variable reference or an optionally quoted
520 * string. This is called for the lhs and rhs of string compares.
521 *
522 * Results:
523 * Sets freeIt if needed,
524 * Sets quoted if string was quoted,
525 * Returns NULL on error,
526 * else returns string - absent any quotes.
527 *
528 * Side Effects:
529 * Moves condExpr to end of this token.
530 *
531 *
532 *-----------------------------------------------------------------------
533 */
534 /* coverity:[+alloc : arg-*2] */
535 static char *
536 CondGetString(Boolean doEval, Boolean *quoted, void **freeIt, Boolean strictLHS)
537 {
538 Buffer buf;
539 char *cp;
540 char *str;
541 int len;
542 int qt;
543 char *start;
544
545 Buf_Init(&buf, 0);
546 str = NULL;
547 *freeIt = NULL;
548 *quoted = qt = *condExpr == '"' ? 1 : 0;
549 if (qt)
550 condExpr++;
551 for (start = condExpr; *condExpr && str == NULL; condExpr++) {
552 switch (*condExpr) {
553 case '\\':
554 if (condExpr[1] != '\0') {
555 condExpr++;
556 Buf_AddByte(&buf, *condExpr);
557 }
558 break;
559 case '"':
560 if (qt) {
561 condExpr++; /* we don't want the quotes */
562 goto got_str;
563 } else
564 Buf_AddByte(&buf, *condExpr); /* likely? */
565 break;
566 case ')':
567 case '!':
568 case '=':
569 case '>':
570 case '<':
571 case ' ':
572 case '\t':
573 if (!qt)
574 goto got_str;
575 else
576 Buf_AddByte(&buf, *condExpr);
577 break;
578 case '$':
579 /* if we are in quotes, then an undefined variable is ok */
580 str = Var_Parse(condExpr, VAR_CMD, (qt ? 0 : doEval),
581 &len, freeIt);
582 if (str == var_Error) {
583 if (*freeIt) {
584 free(*freeIt);
585 *freeIt = NULL;
586 }
587 /*
588 * Even if !doEval, we still report syntax errors, which
589 * is what getting var_Error back with !doEval means.
590 */
591 str = NULL;
592 goto cleanup;
593 }
594 condExpr += len;
595 /*
596 * If the '$' was first char (no quotes), and we are
597 * followed by space, the operator or end of expression,
598 * we are done.
599 */
600 if ((condExpr == start + len) &&
601 (*condExpr == '\0' ||
602 isspace((unsigned char) *condExpr) ||
603 strchr("!=><)", *condExpr))) {
604 goto cleanup;
605 }
606 /*
607 * Nope, we better copy str to buf
608 */
609 for (cp = str; *cp; cp++) {
610 Buf_AddByte(&buf, *cp);
611 }
612 if (*freeIt) {
613 free(*freeIt);
614 *freeIt = NULL;
615 }
616 str = NULL; /* not finished yet */
617 condExpr--; /* don't skip over next char */
618 break;
619 default:
620 if (strictLHS && !qt && *start != '$' &&
621 !isdigit((unsigned char) *start)) {
622 /* lhs must be quoted, a variable reference or number */
623 if (*freeIt) {
624 free(*freeIt);
625 *freeIt = NULL;
626 }
627 str = NULL;
628 goto cleanup;
629 }
630 Buf_AddByte(&buf, *condExpr);
631 break;
632 }
633 }
634 got_str:
635 str = Buf_GetAll(&buf, NULL);
636 *freeIt = str;
637 cleanup:
638 Buf_Destroy(&buf, FALSE);
639 return str;
640 }
641
642 /*-
644 *-----------------------------------------------------------------------
645 * CondToken --
646 * Return the next token from the input.
647 *
648 * Results:
649 * A Token for the next lexical token in the stream.
650 *
651 * Side Effects:
652 * condPushback will be set back to TOK_NONE if it is used.
653 *
654 *-----------------------------------------------------------------------
655 */
656 static Token
657 compare_expression(Boolean doEval)
658 {
659 Token t;
660 char *lhs;
661 char *rhs;
662 char *op;
663 void *lhsFree;
664 void *rhsFree;
665 Boolean lhsQuoted;
666 Boolean rhsQuoted;
667 double left, right;
668
669 t = TOK_ERROR;
670 rhs = NULL;
671 lhsFree = rhsFree = FALSE;
672 lhsQuoted = rhsQuoted = FALSE;
673
674 /*
675 * Parse the variable spec and skip over it, saving its
676 * value in lhs.
677 */
678 lhs = CondGetString(doEval, &lhsQuoted, &lhsFree, lhsStrict);
679 if (!lhs)
680 goto done;
681
682 /*
683 * Skip whitespace to get to the operator
684 */
685 while (isspace((unsigned char) *condExpr))
686 condExpr++;
687
688 /*
689 * Make sure the operator is a valid one. If it isn't a
690 * known relational operator, pretend we got a
691 * != 0 comparison.
692 */
693 op = condExpr;
694 switch (*condExpr) {
695 case '!':
696 case '=':
697 case '<':
698 case '>':
699 if (condExpr[1] == '=') {
700 condExpr += 2;
701 } else {
702 condExpr += 1;
703 }
704 break;
705 default:
706 if (!doEval) {
707 t = TOK_FALSE;
708 goto done;
709 }
710 /* For .ifxxx "..." check for non-empty string. */
711 if (lhsQuoted) {
712 t = lhs[0] != 0;
713 goto done;
714 }
715 /* For .ifxxx <number> compare against zero */
716 if (CondCvtArg(lhs, &left)) {
717 t = left != 0.0;
718 goto done;
719 }
720 /* For .if ${...} check for non-empty string (defProc is ifdef). */
721 if (if_info->form[0] == 0) {
722 t = lhs[0] != 0;
723 goto done;
724 }
725 /* Otherwise action default test ... */
726 t = if_info->defProc(strlen(lhs), lhs) != if_info->doNot;
727 goto done;
728 }
729
730 while (isspace((unsigned char)*condExpr))
731 condExpr++;
732
733 if (*condExpr == '\0') {
734 Parse_Error(PARSE_WARNING,
735 "Missing right-hand-side of operator");
736 goto done;
737 }
738
739 rhs = CondGetString(doEval, &rhsQuoted, &rhsFree, FALSE);
740 if (!rhs)
741 goto done;
742
743 if (rhsQuoted || lhsQuoted) {
744 do_string_compare:
745 if (((*op != '!') && (*op != '=')) || (op[1] != '=')) {
746 Parse_Error(PARSE_WARNING,
747 "String comparison operator should be either == or !=");
748 goto done;
749 }
750
751 if (DEBUG(COND)) {
752 fprintf(debug_file, "lhs = \"%s\", rhs = \"%s\", op = %.2s\n",
753 lhs, rhs, op);
754 }
755 /*
756 * Null-terminate rhs and perform the comparison.
757 * t is set to the result.
758 */
759 if (*op == '=') {
760 t = strcmp(lhs, rhs) == 0;
761 } else {
762 t = strcmp(lhs, rhs) != 0;
763 }
764 } else {
765 /*
766 * rhs is either a float or an integer. Convert both the
767 * lhs and the rhs to a double and compare the two.
768 */
769
770 if (!CondCvtArg(lhs, &left) || !CondCvtArg(rhs, &right))
771 goto do_string_compare;
772
773 if (DEBUG(COND)) {
774 fprintf(debug_file, "left = %f, right = %f, op = %.2s\n", left,
775 right, op);
776 }
777 switch(op[0]) {
778 case '!':
779 if (op[1] != '=') {
780 Parse_Error(PARSE_WARNING,
781 "Unknown operator");
782 goto done;
783 }
784 t = (left != right);
785 break;
786 case '=':
787 if (op[1] != '=') {
788 Parse_Error(PARSE_WARNING,
789 "Unknown operator");
790 goto done;
791 }
792 t = (left == right);
793 break;
794 case '<':
795 if (op[1] == '=') {
796 t = (left <= right);
797 } else {
798 t = (left < right);
799 }
800 break;
801 case '>':
802 if (op[1] == '=') {
803 t = (left >= right);
804 } else {
805 t = (left > right);
806 }
807 break;
808 }
809 }
810
811 done:
812 if (lhsFree)
813 free(lhsFree);
814 if (rhsFree)
815 free(rhsFree);
816 return t;
817 }
818
819 static int
820 get_mpt_arg(char **linePtr, char **argPtr, const char *func MAKE_ATTR_UNUSED)
821 {
822 /*
823 * Use Var_Parse to parse the spec in parens and return
824 * TOK_TRUE if the resulting string is empty.
825 */
826 int length;
827 void *freeIt;
828 char *val;
829 char *cp = *linePtr;
830
831 /* We do all the work here and return the result as the length */
832 *argPtr = NULL;
833
834 val = Var_Parse(cp - 1, VAR_CMD, FALSE, &length, &freeIt);
835 /*
836 * Advance *linePtr to beyond the closing ). Note that
837 * we subtract one because 'length' is calculated from 'cp - 1'.
838 */
839 *linePtr = cp - 1 + length;
840
841 if (val == var_Error) {
842 free(freeIt);
843 return -1;
844 }
845
846 /* A variable is empty when it just contains spaces... 4/15/92, christos */
847 while (isspace(*(unsigned char *)val))
848 val++;
849
850 /*
851 * For consistency with the other functions we can't generate the
852 * true/false here.
853 */
854 length = *val ? 2 : 1;
855 if (freeIt)
856 free(freeIt);
857 return length;
858 }
859
860 static Boolean
861 CondDoEmpty(int arglen, const char *arg MAKE_ATTR_UNUSED)
862 {
863 return arglen == 1;
864 }
865
866 static Token
867 compare_function(Boolean doEval)
868 {
869 static const struct fn_def {
870 const char *fn_name;
871 int fn_name_len;
872 int (*fn_getarg)(char **, char **, const char *);
873 Boolean (*fn_proc)(int, const char *);
874 } fn_defs[] = {
875 { "defined", 7, CondGetArg, CondDoDefined },
876 { "make", 4, CondGetArg, CondDoMake },
877 { "exists", 6, CondGetArg, CondDoExists },
878 { "empty", 5, get_mpt_arg, CondDoEmpty },
879 { "target", 6, CondGetArg, CondDoTarget },
880 { "commands", 8, CondGetArg, CondDoCommands },
881 { NULL, 0, NULL, NULL },
882 };
883 const struct fn_def *fn_def;
884 Token t;
885 char *arg = NULL;
886 int arglen;
887 char *cp = condExpr;
888 char *cp1;
889
890 for (fn_def = fn_defs; fn_def->fn_name != NULL; fn_def++) {
891 if (!istoken(cp, fn_def->fn_name, fn_def->fn_name_len))
892 continue;
893 cp += fn_def->fn_name_len;
894 /* There can only be whitespace before the '(' */
895 while (isspace(*(unsigned char *)cp))
896 cp++;
897 if (*cp != '(')
898 break;
899
900 arglen = fn_def->fn_getarg(&cp, &arg, fn_def->fn_name);
901 if (arglen <= 0) {
902 condExpr = cp;
903 return arglen < 0 ? TOK_ERROR : TOK_FALSE;
904 }
905 /* Evaluate the argument using the required function. */
906 t = !doEval || fn_def->fn_proc(arglen, arg);
907 if (arg)
908 free(arg);
909 condExpr = cp;
910 return t;
911 }
912
913 /* Push anything numeric through the compare expression */
914 cp = condExpr;
915 if (isdigit((unsigned char)cp[0]) || strchr("+-", cp[0]))
916 return compare_expression(doEval);
917
918 /*
919 * Most likely we have a naked token to apply the default function to.
920 * However ".if a == b" gets here when the "a" is unquoted and doesn't
921 * start with a '$'. This surprises people.
922 * If what follows the function argument is a '=' or '!' then the syntax
923 * would be invalid if we did "defined(a)" - so instead treat as an
924 * expression.
925 */
926 arglen = CondGetArg(&cp, &arg, NULL);
927 for (cp1 = cp; isspace(*(unsigned char *)cp1); cp1++)
928 continue;
929 if (*cp1 == '=' || *cp1 == '!')
930 return compare_expression(doEval);
931 condExpr = cp;
932
933 /*
934 * Evaluate the argument using the default function.
935 * This path always treats .if as .ifdef. To get here the character
936 * after .if must have been taken literally, so the argument cannot
937 * be empty - even if it contained a variable expansion.
938 */
939 t = !doEval || if_info->defProc(arglen, arg) != if_info->doNot;
940 if (arg)
941 free(arg);
942 return t;
943 }
944
945 static Token
946 CondToken(Boolean doEval)
947 {
948 Token t;
949
950 t = condPushBack;
951 if (t != TOK_NONE) {
952 condPushBack = TOK_NONE;
953 return t;
954 }
955
956 while (*condExpr == ' ' || *condExpr == '\t') {
957 condExpr++;
958 }
959
960 switch (*condExpr) {
961
962 case '(':
963 condExpr++;
964 return TOK_LPAREN;
965
966 case ')':
967 condExpr++;
968 return TOK_RPAREN;
969
970 case '|':
971 if (condExpr[1] == '|') {
972 condExpr++;
973 }
974 condExpr++;
975 return TOK_OR;
976
977 case '&':
978 if (condExpr[1] == '&') {
979 condExpr++;
980 }
981 condExpr++;
982 return TOK_AND;
983
984 case '!':
985 condExpr++;
986 return TOK_NOT;
987
988 case '#':
989 case '\n':
990 case '\0':
991 return TOK_EOF;
992
993 case '"':
994 case '$':
995 return compare_expression(doEval);
996
997 default:
998 return compare_function(doEval);
999 }
1000 }
1001
1002 /*-
1003 *-----------------------------------------------------------------------
1004 * CondT --
1005 * Parse a single term in the expression. This consists of a terminal
1006 * symbol or TOK_NOT and a terminal symbol (not including the binary
1007 * operators):
1008 * T -> defined(variable) | make(target) | exists(file) | symbol
1009 * T -> ! T | ( E )
1010 *
1011 * Results:
1012 * TOK_TRUE, TOK_FALSE or TOK_ERROR.
1013 *
1014 * Side Effects:
1015 * Tokens are consumed.
1016 *
1017 *-----------------------------------------------------------------------
1018 */
1019 static Token
1020 CondT(Boolean doEval)
1021 {
1022 Token t;
1023
1024 t = CondToken(doEval);
1025
1026 if (t == TOK_EOF) {
1027 /*
1028 * If we reached the end of the expression, the expression
1029 * is malformed...
1030 */
1031 t = TOK_ERROR;
1032 } else if (t == TOK_LPAREN) {
1033 /*
1034 * T -> ( E )
1035 */
1036 t = CondE(doEval);
1037 if (t != TOK_ERROR) {
1038 if (CondToken(doEval) != TOK_RPAREN) {
1039 t = TOK_ERROR;
1040 }
1041 }
1042 } else if (t == TOK_NOT) {
1043 t = CondT(doEval);
1044 if (t == TOK_TRUE) {
1045 t = TOK_FALSE;
1046 } else if (t == TOK_FALSE) {
1047 t = TOK_TRUE;
1048 }
1049 }
1050 return (t);
1051 }
1052
1053 /*-
1055 *-----------------------------------------------------------------------
1056 * CondF --
1057 * Parse a conjunctive factor (nice name, wot?)
1058 * F -> T && F | T
1059 *
1060 * Results:
1061 * TOK_TRUE, TOK_FALSE or TOK_ERROR
1062 *
1063 * Side Effects:
1064 * Tokens are consumed.
1065 *
1066 *-----------------------------------------------------------------------
1067 */
1068 static Token
1069 CondF(Boolean doEval)
1070 {
1071 Token l, o;
1072
1073 l = CondT(doEval);
1074 if (l != TOK_ERROR) {
1075 o = CondToken(doEval);
1076
1077 if (o == TOK_AND) {
1078 /*
1079 * F -> T && F
1080 *
1081 * If T is TOK_FALSE, the whole thing will be TOK_FALSE, but we have to
1082 * parse the r.h.s. anyway (to throw it away).
1083 * If T is TOK_TRUE, the result is the r.h.s., be it an TOK_ERROR or no.
1084 */
1085 if (l == TOK_TRUE) {
1086 l = CondF(doEval);
1087 } else {
1088 (void)CondF(FALSE);
1089 }
1090 } else {
1091 /*
1092 * F -> T
1093 */
1094 CondPushBack(o);
1095 }
1096 }
1097 return (l);
1098 }
1099
1100 /*-
1102 *-----------------------------------------------------------------------
1103 * CondE --
1104 * Main expression production.
1105 * E -> F || E | F
1106 *
1107 * Results:
1108 * TOK_TRUE, TOK_FALSE or TOK_ERROR.
1109 *
1110 * Side Effects:
1111 * Tokens are, of course, consumed.
1112 *
1113 *-----------------------------------------------------------------------
1114 */
1115 static Token
1116 CondE(Boolean doEval)
1117 {
1118 Token l, o;
1119
1120 l = CondF(doEval);
1121 if (l != TOK_ERROR) {
1122 o = CondToken(doEval);
1123
1124 if (o == TOK_OR) {
1125 /*
1126 * E -> F || E
1127 *
1128 * A similar thing occurs for ||, except that here we make sure
1129 * the l.h.s. is TOK_FALSE before we bother to evaluate the r.h.s.
1130 * Once again, if l is TOK_FALSE, the result is the r.h.s. and once
1131 * again if l is TOK_TRUE, we parse the r.h.s. to throw it away.
1132 */
1133 if (l == TOK_FALSE) {
1134 l = CondE(doEval);
1135 } else {
1136 (void)CondE(FALSE);
1137 }
1138 } else {
1139 /*
1140 * E -> F
1141 */
1142 CondPushBack(o);
1143 }
1144 }
1145 return (l);
1146 }
1147
1148 /*-
1149 *-----------------------------------------------------------------------
1150 * Cond_EvalExpression --
1151 * Evaluate an expression in the passed line. The expression
1152 * consists of &&, ||, !, make(target), defined(variable)
1153 * and parenthetical groupings thereof.
1154 *
1155 * Results:
1156 * COND_PARSE if the condition was valid grammatically
1157 * COND_INVALID if not a valid conditional.
1158 *
1159 * (*value) is set to the boolean value of the condition
1160 *
1161 * Side Effects:
1162 * None.
1163 *
1164 *-----------------------------------------------------------------------
1165 */
1166 int
1167 Cond_EvalExpression(const struct If *info, char *line, Boolean *value, int eprint, Boolean strictLHS)
1168 {
1169 static const struct If *dflt_info;
1170 const struct If *sv_if_info = if_info;
1171 char *sv_condExpr = condExpr;
1172 Token sv_condPushBack = condPushBack;
1173 int rval;
1174
1175 lhsStrict = strictLHS;
1176
1177 while (*line == ' ' || *line == '\t')
1178 line++;
1179
1180 if (info == NULL && (info = dflt_info) == NULL) {
1181 /* Scan for the entry for .if - it can't be first */
1182 for (info = ifs; ; info++)
1183 if (info->form[0] == 0)
1184 break;
1185 dflt_info = info;
1186 }
1187
1188 if_info = info != NULL ? info : ifs + 4;
1189 condExpr = line;
1190 condPushBack = TOK_NONE;
1191
1192 rval = do_Cond_EvalExpression(value);
1193
1194 if (rval == COND_INVALID && eprint)
1195 Parse_Error(PARSE_FATAL, "Malformed conditional (%s)", line);
1196
1197 if_info = sv_if_info;
1198 condExpr = sv_condExpr;
1199 condPushBack = sv_condPushBack;
1200
1201 return rval;
1202 }
1203
1204 static int
1205 do_Cond_EvalExpression(Boolean *value)
1206 {
1207
1208 switch (CondE(TRUE)) {
1209 case TOK_TRUE:
1210 if (CondToken(TRUE) == TOK_EOF) {
1211 *value = TRUE;
1212 return COND_PARSE;
1213 }
1214 break;
1215 case TOK_FALSE:
1216 if (CondToken(TRUE) == TOK_EOF) {
1217 *value = FALSE;
1218 return COND_PARSE;
1219 }
1220 break;
1221 default:
1222 case TOK_ERROR:
1223 break;
1224 }
1225
1226 return COND_INVALID;
1227 }
1228
1229
1230 /*-
1232 *-----------------------------------------------------------------------
1233 * Cond_Eval --
1234 * Evaluate the conditional in the passed line. The line
1235 * looks like this:
1236 * .<cond-type> <expr>
1237 * where <cond-type> is any of if, ifmake, ifnmake, ifdef,
1238 * ifndef, elif, elifmake, elifnmake, elifdef, elifndef
1239 * and <expr> consists of &&, ||, !, make(target), defined(variable)
1240 * and parenthetical groupings thereof.
1241 *
1242 * Input:
1243 * line Line to parse
1244 *
1245 * Results:
1246 * COND_PARSE if should parse lines after the conditional
1247 * COND_SKIP if should skip lines after the conditional
1248 * COND_INVALID if not a valid conditional.
1249 *
1250 * Side Effects:
1251 * None.
1252 *
1253 * Note that the states IF_ACTIVE and ELSE_ACTIVE are only different in order
1254 * to detect splurious .else lines (as are SKIP_TO_ELSE and SKIP_TO_ENDIF)
1255 * otherwise .else could be treated as '.elif 1'.
1256 *
1257 *-----------------------------------------------------------------------
1258 */
1259 int
1260 Cond_Eval(char *line)
1261 {
1262 #define MAXIF 128 /* maximum depth of .if'ing */
1263 #define MAXIF_BUMP 32 /* how much to grow by */
1264 enum if_states {
1265 IF_ACTIVE, /* .if or .elif part active */
1266 ELSE_ACTIVE, /* .else part active */
1267 SEARCH_FOR_ELIF, /* searching for .elif/else to execute */
1268 SKIP_TO_ELSE, /* has been true, but not seen '.else' */
1269 SKIP_TO_ENDIF /* nothing else to execute */
1270 };
1271 static enum if_states *cond_state = NULL;
1272 static unsigned int max_if_depth = MAXIF;
1273
1274 const struct If *ifp;
1275 Boolean isElif;
1276 Boolean value;
1277 int level; /* Level at which to report errors. */
1278 enum if_states state;
1279
1280 level = PARSE_FATAL;
1281 if (!cond_state) {
1282 cond_state = bmake_malloc(max_if_depth * sizeof(*cond_state));
1283 cond_state[0] = IF_ACTIVE;
1284 }
1285 /* skip leading character (the '.') and any whitespace */
1286 for (line++; *line == ' ' || *line == '\t'; line++)
1287 continue;
1288
1289 /* Find what type of if we're dealing with. */
1290 if (line[0] == 'e') {
1291 if (line[1] != 'l') {
1292 if (!istoken(line + 1, "ndif", 4))
1293 return COND_INVALID;
1294 /* End of conditional section */
1295 if (cond_depth == cond_min_depth) {
1296 Parse_Error(level, "if-less endif");
1297 return COND_PARSE;
1298 }
1299 /* Return state for previous conditional */
1300 cond_depth--;
1301 return cond_state[cond_depth] <= ELSE_ACTIVE ? COND_PARSE : COND_SKIP;
1302 }
1303
1304 /* Quite likely this is 'else' or 'elif' */
1305 line += 2;
1306 if (istoken(line, "se", 2)) {
1307 /* It is else... */
1308 if (cond_depth == cond_min_depth) {
1309 Parse_Error(level, "if-less else");
1310 return COND_PARSE;
1311 }
1312
1313 state = cond_state[cond_depth];
1314 switch (state) {
1315 case SEARCH_FOR_ELIF:
1316 state = ELSE_ACTIVE;
1317 break;
1318 case ELSE_ACTIVE:
1319 case SKIP_TO_ENDIF:
1320 Parse_Error(PARSE_WARNING, "extra else");
1321 /* FALLTHROUGH */
1322 default:
1323 case IF_ACTIVE:
1324 case SKIP_TO_ELSE:
1325 state = SKIP_TO_ENDIF;
1326 break;
1327 }
1328 cond_state[cond_depth] = state;
1329 return state <= ELSE_ACTIVE ? COND_PARSE : COND_SKIP;
1330 }
1331 /* Assume for now it is an elif */
1332 isElif = TRUE;
1333 } else
1334 isElif = FALSE;
1335
1336 if (line[0] != 'i' || line[1] != 'f')
1337 /* Not an ifxxx or elifxxx line */
1338 return COND_INVALID;
1339
1340 /*
1341 * Figure out what sort of conditional it is -- what its default
1342 * function is, etc. -- by looking in the table of valid "ifs"
1343 */
1344 line += 2;
1345 for (ifp = ifs; ; ifp++) {
1346 if (ifp->form == NULL)
1347 return COND_INVALID;
1348 if (istoken(ifp->form, line, ifp->formlen)) {
1349 line += ifp->formlen;
1350 break;
1351 }
1352 }
1353
1354 /* Now we know what sort of 'if' it is... */
1355
1356 if (isElif) {
1357 if (cond_depth == cond_min_depth) {
1358 Parse_Error(level, "if-less elif");
1359 return COND_PARSE;
1360 }
1361 state = cond_state[cond_depth];
1362 if (state == SKIP_TO_ENDIF || state == ELSE_ACTIVE) {
1363 Parse_Error(PARSE_WARNING, "extra elif");
1364 cond_state[cond_depth] = SKIP_TO_ENDIF;
1365 return COND_SKIP;
1366 }
1367 if (state != SEARCH_FOR_ELIF) {
1368 /* Either just finished the 'true' block, or already SKIP_TO_ELSE */
1369 cond_state[cond_depth] = SKIP_TO_ELSE;
1370 return COND_SKIP;
1371 }
1372 } else {
1373 /* Normal .if */
1374 if (cond_depth + 1 >= max_if_depth) {
1375 /*
1376 * This is rare, but not impossible.
1377 * In meta mode, dirdeps.mk (only runs at level 0)
1378 * can need more than the default.
1379 */
1380 max_if_depth += MAXIF_BUMP;
1381 cond_state = bmake_realloc(cond_state, max_if_depth *
1382 sizeof(*cond_state));
1383 }
1384 state = cond_state[cond_depth];
1385 cond_depth++;
1386 if (state > ELSE_ACTIVE) {
1387 /* If we aren't parsing the data, treat as always false */
1388 cond_state[cond_depth] = SKIP_TO_ELSE;
1389 return COND_SKIP;
1390 }
1391 }
1392
1393 /* And evaluate the conditional expresssion */
1394 if (Cond_EvalExpression(ifp, line, &value, 1, TRUE) == COND_INVALID) {
1395 /* Syntax error in conditional, error message already output. */
1396 /* Skip everything to matching .endif */
1397 cond_state[cond_depth] = SKIP_TO_ELSE;
1398 return COND_SKIP;
1399 }
1400
1401 if (!value) {
1402 cond_state[cond_depth] = SEARCH_FOR_ELIF;
1403 return COND_SKIP;
1404 }
1405 cond_state[cond_depth] = IF_ACTIVE;
1406 return COND_PARSE;
1407 }
1408
1409
1410
1411 /*-
1413 *-----------------------------------------------------------------------
1414 * Cond_End --
1415 * Make sure everything's clean at the end of a makefile.
1416 *
1417 * Results:
1418 * None.
1419 *
1420 * Side Effects:
1421 * Parse_Error will be called if open conditionals are around.
1422 *
1423 *-----------------------------------------------------------------------
1424 */
1425 void
1426 Cond_restore_depth(unsigned int saved_depth)
1427 {
1428 int open_conds = cond_depth - cond_min_depth;
1429
1430 if (open_conds != 0 || saved_depth > cond_depth) {
1431 Parse_Error(PARSE_FATAL, "%d open conditional%s", open_conds,
1432 open_conds == 1 ? "" : "s");
1433 cond_depth = cond_min_depth;
1434 }
1435
1436 cond_min_depth = saved_depth;
1437 }
1438
1439 unsigned int
1440 Cond_save_depth(void)
1441 {
1442 int depth = cond_min_depth;
1443
1444 cond_min_depth = cond_depth;
1445 return depth;
1446 }
1447