1 /* $NetBSD: cond.c,v 1.75 2017/04/16 20:59:04 riastradh 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 1.75 2017/04/16 20:59:04 riastradh 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 1.75 2017/04/16 20:59:04 riastradh 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 <assert.h>
95 #include <ctype.h>
96 #include <errno.h> /* For strtoul() error checking */
97
98 #include "make.h"
99 #include "hash.h"
100 #include "dir.h"
101 #include "buf.h"
102
103 /*
104 * The parsing of conditional expressions is based on this grammar:
105 * E -> F || E
106 * E -> F
107 * F -> T && F
108 * F -> T
109 * T -> defined(variable)
110 * T -> make(target)
111 * T -> exists(file)
112 * T -> empty(varspec)
113 * T -> target(name)
114 * T -> commands(name)
115 * T -> symbol
116 * T -> $(varspec) op value
117 * T -> $(varspec) == "string"
118 * T -> $(varspec) != "string"
119 * T -> "string"
120 * T -> ( E )
121 * T -> ! T
122 * op -> == | != | > | < | >= | <=
123 *
124 * 'symbol' is some other symbol to which the default function (condDefProc)
125 * is applied.
126 *
127 * Tokens are scanned from the 'condExpr' string. The scanner (CondToken)
128 * will return TOK_AND for '&' and '&&', TOK_OR for '|' and '||',
129 * TOK_NOT for '!', TOK_LPAREN for '(', TOK_RPAREN for ')' and will evaluate
130 * the other terminal symbols, using either the default function or the
131 * function given in the terminal, and return the result as either TOK_TRUE
132 * or TOK_FALSE.
133 *
134 * TOK_FALSE is 0 and TOK_TRUE 1 so we can directly assign C comparisons.
135 *
136 * All Non-Terminal functions (CondE, CondF and CondT) return TOK_ERROR on
137 * error.
138 */
139 typedef enum {
140 TOK_FALSE = 0, TOK_TRUE = 1, TOK_AND, TOK_OR, TOK_NOT,
141 TOK_LPAREN, TOK_RPAREN, TOK_EOF, TOK_NONE, TOK_ERROR
142 } Token;
143
144 /*-
145 * Structures to handle elegantly the different forms of #if's. The
146 * last two fields are stored in condInvert and condDefProc, respectively.
147 */
148 static void CondPushBack(Token);
149 static int CondGetArg(char **, char **, const char *);
150 static Boolean CondDoDefined(int, const char *);
151 static int CondStrMatch(const void *, const void *);
152 static Boolean CondDoMake(int, const char *);
153 static Boolean CondDoExists(int, const char *);
154 static Boolean CondDoTarget(int, const char *);
155 static Boolean CondDoCommands(int, const char *);
156 static Boolean CondCvtArg(char *, double *);
157 static Token CondToken(Boolean);
158 static Token CondT(Boolean);
159 static Token CondF(Boolean);
160 static Token CondE(Boolean);
161 static int do_Cond_EvalExpression(Boolean *);
162
163 static const struct If {
164 const char *form; /* Form of if */
165 int formlen; /* Length of form */
166 Boolean doNot; /* TRUE if default function should be negated */
167 Boolean (*defProc)(int, const char *); /* Default function to apply */
168 } ifs[] = {
169 { "def", 3, FALSE, CondDoDefined },
170 { "ndef", 4, TRUE, CondDoDefined },
171 { "make", 4, FALSE, CondDoMake },
172 { "nmake", 5, TRUE, CondDoMake },
173 { "", 0, FALSE, CondDoDefined },
174 { NULL, 0, FALSE, NULL }
175 };
176
177 static const struct If *if_info; /* Info for current statement */
178 static char *condExpr; /* The expression to parse */
179 static Token condPushBack=TOK_NONE; /* Single push-back token used in
180 * parsing */
181
182 static unsigned int cond_depth = 0; /* current .if nesting level */
183 static unsigned int cond_min_depth = 0; /* depth at makefile open */
184
185 /*
186 * Indicate when we should be strict about lhs of comparisons.
187 * TRUE when Cond_EvalExpression is called from Cond_Eval (.if etc)
188 * FALSE when Cond_EvalExpression is called from var.c:ApplyModifiers
189 * since lhs is already expanded and we cannot tell if
190 * it was a variable reference or not.
191 */
192 static Boolean lhsStrict;
193
194 static int
istoken(const char * str,const char * tok,size_t len)195 istoken(const char *str, const char *tok, size_t len)
196 {
197 return strncmp(str, tok, len) == 0 && !isalpha((unsigned char)str[len]);
198 }
199
200 /*-
201 *-----------------------------------------------------------------------
202 * CondPushBack --
203 * Push back the most recent token read. We only need one level of
204 * this, so the thing is just stored in 'condPushback'.
205 *
206 * Input:
207 * t Token to push back into the "stream"
208 *
209 * Results:
210 * None.
211 *
212 * Side Effects:
213 * condPushback is overwritten.
214 *
215 *-----------------------------------------------------------------------
216 */
217 static void
CondPushBack(Token t)218 CondPushBack(Token t)
219 {
220 condPushBack = t;
221 }
222
223 /*-
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
CondGetArg(char ** linePtr,char ** argPtr,const char * func)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, VARF_UNDEFERR|VARF_WANTRES,
294 &len, &freeIt);
295 Buf_AddBytes(&buf, strlen(cp2), cp2);
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 /*-
327 *-----------------------------------------------------------------------
328 * CondDoDefined --
329 * Handle the 'defined' function for conditionals.
330 *
331 * Results:
332 * TRUE if the given variable is defined.
333 *
334 * Side Effects:
335 * None.
336 *
337 *-----------------------------------------------------------------------
338 */
339 static Boolean
CondDoDefined(int argLen MAKE_ATTR_UNUSED,const char * arg)340 CondDoDefined(int argLen MAKE_ATTR_UNUSED, const char *arg)
341 {
342 char *p1;
343 Boolean result;
344
345 if (Var_Value(arg, VAR_CMD, &p1) != NULL) {
346 result = TRUE;
347 } else {
348 result = FALSE;
349 }
350
351 free(p1);
352 return (result);
353 }
354
355 /*-
356 *-----------------------------------------------------------------------
357 * CondStrMatch --
358 * Front-end for Str_Match so it returns 0 on match and non-zero
359 * on mismatch. Callback function for CondDoMake via Lst_Find
360 *
361 * Results:
362 * 0 if string matches pattern
363 *
364 * Side Effects:
365 * None
366 *
367 *-----------------------------------------------------------------------
368 */
369 static int
CondStrMatch(const void * string,const void * pattern)370 CondStrMatch(const void *string, const void *pattern)
371 {
372 return(!Str_Match(string, pattern));
373 }
374
375 /*-
376 *-----------------------------------------------------------------------
377 * CondDoMake --
378 * Handle the 'make' function for conditionals.
379 *
380 * Results:
381 * TRUE if the given target is being made.
382 *
383 * Side Effects:
384 * None.
385 *
386 *-----------------------------------------------------------------------
387 */
388 static Boolean
CondDoMake(int argLen MAKE_ATTR_UNUSED,const char * arg)389 CondDoMake(int argLen MAKE_ATTR_UNUSED, const char *arg)
390 {
391 return Lst_Find(create, arg, CondStrMatch) != NULL;
392 }
393
394 /*-
395 *-----------------------------------------------------------------------
396 * CondDoExists --
397 * See if the given file exists.
398 *
399 * Results:
400 * TRUE if the file exists and FALSE if it does not.
401 *
402 * Side Effects:
403 * None.
404 *
405 *-----------------------------------------------------------------------
406 */
407 static Boolean
CondDoExists(int argLen MAKE_ATTR_UNUSED,const char * arg)408 CondDoExists(int argLen MAKE_ATTR_UNUSED, const char *arg)
409 {
410 Boolean result;
411 char *path;
412
413 path = Dir_FindFile(arg, dirSearchPath);
414 if (DEBUG(COND)) {
415 fprintf(debug_file, "exists(%s) result is \"%s\"\n",
416 arg, path ? path : "");
417 }
418 if (path != NULL) {
419 result = TRUE;
420 free(path);
421 } else {
422 result = FALSE;
423 }
424 return (result);
425 }
426
427 /*-
428 *-----------------------------------------------------------------------
429 * CondDoTarget --
430 * See if the given node exists and is an actual target.
431 *
432 * Results:
433 * TRUE if the node exists as a target and FALSE if it does not.
434 *
435 * Side Effects:
436 * None.
437 *
438 *-----------------------------------------------------------------------
439 */
440 static Boolean
CondDoTarget(int argLen MAKE_ATTR_UNUSED,const char * arg)441 CondDoTarget(int argLen MAKE_ATTR_UNUSED, const char *arg)
442 {
443 GNode *gn;
444
445 gn = Targ_FindNode(arg, TARG_NOCREATE);
446 return (gn != NULL) && !OP_NOP(gn->type);
447 }
448
449 /*-
450 *-----------------------------------------------------------------------
451 * CondDoCommands --
452 * See if the given node exists and is an actual target with commands
453 * associated with it.
454 *
455 * Results:
456 * TRUE if the node exists as a target and has commands associated with
457 * it and FALSE if it does not.
458 *
459 * Side Effects:
460 * None.
461 *
462 *-----------------------------------------------------------------------
463 */
464 static Boolean
CondDoCommands(int argLen MAKE_ATTR_UNUSED,const char * arg)465 CondDoCommands(int argLen MAKE_ATTR_UNUSED, const char *arg)
466 {
467 GNode *gn;
468
469 gn = Targ_FindNode(arg, TARG_NOCREATE);
470 return (gn != NULL) && !OP_NOP(gn->type) && !Lst_IsEmpty(gn->commands);
471 }
472
473 /*-
474 *-----------------------------------------------------------------------
475 * CondCvtArg --
476 * Convert the given number into a double.
477 * We try a base 10 or 16 integer conversion first, if that fails
478 * then we try a floating point conversion instead.
479 *
480 * Results:
481 * Sets 'value' to double value of string.
482 * Returns 'true' if the convertion suceeded
483 *
484 *-----------------------------------------------------------------------
485 */
486 static Boolean
CondCvtArg(char * str,double * value)487 CondCvtArg(char *str, double *value)
488 {
489 char *eptr, ech;
490 unsigned long l_val;
491 double d_val;
492
493 errno = 0;
494 if (!*str) {
495 *value = (double)0;
496 return TRUE;
497 }
498 l_val = strtoul(str, &eptr, str[1] == 'x' ? 16 : 10);
499 ech = *eptr;
500 if (ech == 0 && errno != ERANGE) {
501 d_val = str[0] == '-' ? -(double)-l_val : (double)l_val;
502 } else {
503 if (ech != 0 && ech != '.' && ech != 'e' && ech != 'E')
504 return FALSE;
505 d_val = strtod(str, &eptr);
506 if (*eptr)
507 return FALSE;
508 }
509
510 *value = d_val;
511 return TRUE;
512 }
513
514 /*-
515 *-----------------------------------------------------------------------
516 * CondGetString --
517 * Get a string from a variable reference or an optionally quoted
518 * string. This is called for the lhs and rhs of string compares.
519 *
520 * Results:
521 * Sets freeIt if needed,
522 * Sets quoted if string was quoted,
523 * Returns NULL on error,
524 * else returns string - absent any quotes.
525 *
526 * Side Effects:
527 * Moves condExpr to end of this token.
528 *
529 *
530 *-----------------------------------------------------------------------
531 */
532 /* coverity:[+alloc : arg-*2] */
533 static char *
CondGetString(Boolean doEval,Boolean * quoted,void ** freeIt,Boolean strictLHS)534 CondGetString(Boolean doEval, Boolean *quoted, void **freeIt, Boolean strictLHS)
535 {
536 Buffer buf;
537 char *cp;
538 char *str;
539 int len;
540 int qt;
541 char *start;
542
543 Buf_Init(&buf, 0);
544 str = NULL;
545 *freeIt = NULL;
546 *quoted = qt = *condExpr == '"' ? 1 : 0;
547 if (qt)
548 condExpr++;
549 for (start = condExpr; *condExpr && str == NULL; condExpr++) {
550 switch (*condExpr) {
551 case '\\':
552 if (condExpr[1] != '\0') {
553 condExpr++;
554 Buf_AddByte(&buf, *condExpr);
555 }
556 break;
557 case '"':
558 if (qt) {
559 condExpr++; /* we don't want the quotes */
560 goto got_str;
561 } else
562 Buf_AddByte(&buf, *condExpr); /* likely? */
563 break;
564 case ')':
565 case '!':
566 case '=':
567 case '>':
568 case '<':
569 case ' ':
570 case '\t':
571 if (!qt)
572 goto got_str;
573 else
574 Buf_AddByte(&buf, *condExpr);
575 break;
576 case '$':
577 /* if we are in quotes, then an undefined variable is ok */
578 str = Var_Parse(condExpr, VAR_CMD,
579 ((!qt && doEval) ? VARF_UNDEFERR : 0) |
580 VARF_WANTRES, &len, freeIt);
581 if (str == var_Error) {
582 if (*freeIt) {
583 free(*freeIt);
584 *freeIt = NULL;
585 }
586 /*
587 * Even if !doEval, we still report syntax errors, which
588 * is what getting var_Error back with !doEval means.
589 */
590 str = NULL;
591 goto cleanup;
592 }
593 condExpr += len;
594 /*
595 * If the '$' was first char (no quotes), and we are
596 * followed by space, the operator or end of expression,
597 * we are done.
598 */
599 if ((condExpr == start + len) &&
600 (*condExpr == '\0' ||
601 isspace((unsigned char) *condExpr) ||
602 strchr("!=><)", *condExpr))) {
603 goto cleanup;
604 }
605 /*
606 * Nope, we better copy str to buf
607 */
608 for (cp = str; *cp; cp++) {
609 Buf_AddByte(&buf, *cp);
610 }
611 if (*freeIt) {
612 free(*freeIt);
613 *freeIt = NULL;
614 }
615 str = NULL; /* not finished yet */
616 condExpr--; /* don't skip over next char */
617 break;
618 default:
619 if (strictLHS && !qt && *start != '$' &&
620 !isdigit((unsigned char) *start)) {
621 /* lhs must be quoted, a variable reference or number */
622 if (*freeIt) {
623 free(*freeIt);
624 *freeIt = NULL;
625 }
626 str = NULL;
627 goto cleanup;
628 }
629 Buf_AddByte(&buf, *condExpr);
630 break;
631 }
632 }
633 got_str:
634 str = Buf_GetAll(&buf, NULL);
635 *freeIt = str;
636 cleanup:
637 Buf_Destroy(&buf, FALSE);
638 return str;
639 }
640
641 /*-
642 *-----------------------------------------------------------------------
643 * CondToken --
644 * Return the next token from the input.
645 *
646 * Results:
647 * A Token for the next lexical token in the stream.
648 *
649 * Side Effects:
650 * condPushback will be set back to TOK_NONE if it is used.
651 *
652 *-----------------------------------------------------------------------
653 */
654 static Token
compare_expression(Boolean doEval)655 compare_expression(Boolean doEval)
656 {
657 Token t;
658 char *lhs;
659 char *rhs;
660 char *op;
661 void *lhsFree;
662 void *rhsFree;
663 Boolean lhsQuoted;
664 Boolean rhsQuoted;
665 double left, right;
666
667 t = TOK_ERROR;
668 rhs = NULL;
669 lhsFree = rhsFree = FALSE;
670 lhsQuoted = rhsQuoted = FALSE;
671
672 /*
673 * Parse the variable spec and skip over it, saving its
674 * value in lhs.
675 */
676 lhs = CondGetString(doEval, &lhsQuoted, &lhsFree, lhsStrict);
677 if (!lhs)
678 goto done;
679
680 /*
681 * Skip whitespace to get to the operator
682 */
683 while (isspace((unsigned char) *condExpr))
684 condExpr++;
685
686 /*
687 * Make sure the operator is a valid one. If it isn't a
688 * known relational operator, pretend we got a
689 * != 0 comparison.
690 */
691 op = condExpr;
692 switch (*condExpr) {
693 case '!':
694 case '=':
695 case '<':
696 case '>':
697 if (condExpr[1] == '=') {
698 condExpr += 2;
699 } else {
700 condExpr += 1;
701 }
702 break;
703 default:
704 if (!doEval) {
705 t = TOK_FALSE;
706 goto done;
707 }
708 /* For .ifxxx "..." check for non-empty string. */
709 if (lhsQuoted) {
710 t = lhs[0] != 0;
711 goto done;
712 }
713 /* For .ifxxx <number> compare against zero */
714 if (CondCvtArg(lhs, &left)) {
715 t = left != 0.0;
716 goto done;
717 }
718 /* For .if ${...} check for non-empty string (defProc is ifdef). */
719 if (if_info->form[0] == 0) {
720 t = lhs[0] != 0;
721 goto done;
722 }
723 /* Otherwise action default test ... */
724 t = if_info->defProc(strlen(lhs), lhs) != if_info->doNot;
725 goto done;
726 }
727
728 while (isspace((unsigned char)*condExpr))
729 condExpr++;
730
731 if (*condExpr == '\0') {
732 Parse_Error(PARSE_WARNING,
733 "Missing right-hand-side of operator");
734 goto done;
735 }
736
737 rhs = CondGetString(doEval, &rhsQuoted, &rhsFree, FALSE);
738 if (!rhs)
739 goto done;
740
741 if (rhsQuoted || lhsQuoted) {
742 do_string_compare:
743 if (((*op != '!') && (*op != '=')) || (op[1] != '=')) {
744 Parse_Error(PARSE_WARNING,
745 "String comparison operator should be either == or !=");
746 goto done;
747 }
748
749 if (DEBUG(COND)) {
750 fprintf(debug_file, "lhs = \"%s\", rhs = \"%s\", op = %.2s\n",
751 lhs, rhs, op);
752 }
753 /*
754 * Null-terminate rhs and perform the comparison.
755 * t is set to the result.
756 */
757 if (*op == '=') {
758 t = strcmp(lhs, rhs) == 0;
759 } else {
760 t = strcmp(lhs, rhs) != 0;
761 }
762 } else {
763 /*
764 * rhs is either a float or an integer. Convert both the
765 * lhs and the rhs to a double and compare the two.
766 */
767
768 if (!CondCvtArg(lhs, &left) || !CondCvtArg(rhs, &right))
769 goto do_string_compare;
770
771 if (DEBUG(COND)) {
772 fprintf(debug_file, "left = %f, right = %f, op = %.2s\n", left,
773 right, op);
774 }
775 switch(op[0]) {
776 case '!':
777 if (op[1] != '=') {
778 Parse_Error(PARSE_WARNING,
779 "Unknown operator");
780 goto done;
781 }
782 t = (left != right);
783 break;
784 case '=':
785 if (op[1] != '=') {
786 Parse_Error(PARSE_WARNING,
787 "Unknown operator");
788 goto done;
789 }
790 t = (left == right);
791 break;
792 case '<':
793 if (op[1] == '=') {
794 t = (left <= right);
795 } else {
796 t = (left < right);
797 }
798 break;
799 case '>':
800 if (op[1] == '=') {
801 t = (left >= right);
802 } else {
803 t = (left > right);
804 }
805 break;
806 }
807 }
808
809 done:
810 free(lhsFree);
811 free(rhsFree);
812 return t;
813 }
814
815 static int
get_mpt_arg(char ** linePtr,char ** argPtr,const char * func MAKE_ATTR_UNUSED)816 get_mpt_arg(char **linePtr, char **argPtr, const char *func MAKE_ATTR_UNUSED)
817 {
818 /*
819 * Use Var_Parse to parse the spec in parens and return
820 * TOK_TRUE if the resulting string is empty.
821 */
822 int length;
823 void *freeIt;
824 char *val;
825 char *cp = *linePtr;
826
827 /* We do all the work here and return the result as the length */
828 *argPtr = NULL;
829
830 val = Var_Parse(cp - 1, VAR_CMD, VARF_WANTRES, &length, &freeIt);
831 /*
832 * Advance *linePtr to beyond the closing ). Note that
833 * we subtract one because 'length' is calculated from 'cp - 1'.
834 */
835 *linePtr = cp - 1 + length;
836
837 if (val == var_Error) {
838 free(freeIt);
839 return -1;
840 }
841
842 /* A variable is empty when it just contains spaces... 4/15/92, christos */
843 while (isspace(*(unsigned char *)val))
844 val++;
845
846 /*
847 * For consistency with the other functions we can't generate the
848 * true/false here.
849 */
850 length = *val ? 2 : 1;
851 free(freeIt);
852 return length;
853 }
854
855 static Boolean
CondDoEmpty(int arglen,const char * arg MAKE_ATTR_UNUSED)856 CondDoEmpty(int arglen, const char *arg MAKE_ATTR_UNUSED)
857 {
858 return arglen == 1;
859 }
860
861 static Token
compare_function(Boolean doEval)862 compare_function(Boolean doEval)
863 {
864 static const struct fn_def {
865 const char *fn_name;
866 int fn_name_len;
867 int (*fn_getarg)(char **, char **, const char *);
868 Boolean (*fn_proc)(int, const char *);
869 } fn_defs[] = {
870 { "defined", 7, CondGetArg, CondDoDefined },
871 { "make", 4, CondGetArg, CondDoMake },
872 { "exists", 6, CondGetArg, CondDoExists },
873 { "empty", 5, get_mpt_arg, CondDoEmpty },
874 { "target", 6, CondGetArg, CondDoTarget },
875 { "commands", 8, CondGetArg, CondDoCommands },
876 { NULL, 0, NULL, NULL },
877 };
878 const struct fn_def *fn_def;
879 Token t;
880 char *arg = NULL;
881 int arglen;
882 char *cp = condExpr;
883 char *cp1;
884
885 for (fn_def = fn_defs; fn_def->fn_name != NULL; fn_def++) {
886 if (!istoken(cp, fn_def->fn_name, fn_def->fn_name_len))
887 continue;
888 cp += fn_def->fn_name_len;
889 /* There can only be whitespace before the '(' */
890 while (isspace(*(unsigned char *)cp))
891 cp++;
892 if (*cp != '(')
893 break;
894
895 arglen = fn_def->fn_getarg(&cp, &arg, fn_def->fn_name);
896 if (arglen <= 0) {
897 condExpr = cp;
898 return arglen < 0 ? TOK_ERROR : TOK_FALSE;
899 }
900 /* Evaluate the argument using the required function. */
901 t = !doEval || fn_def->fn_proc(arglen, arg);
902 free(arg);
903 condExpr = cp;
904 return t;
905 }
906
907 /* Push anything numeric through the compare expression */
908 cp = condExpr;
909 if (isdigit((unsigned char)cp[0]) || strchr("+-", cp[0]))
910 return compare_expression(doEval);
911
912 /*
913 * Most likely we have a naked token to apply the default function to.
914 * However ".if a == b" gets here when the "a" is unquoted and doesn't
915 * start with a '$'. This surprises people.
916 * If what follows the function argument is a '=' or '!' then the syntax
917 * would be invalid if we did "defined(a)" - so instead treat as an
918 * expression.
919 */
920 arglen = CondGetArg(&cp, &arg, NULL);
921 for (cp1 = cp; isspace(*(unsigned char *)cp1); cp1++)
922 continue;
923 if (*cp1 == '=' || *cp1 == '!')
924 return compare_expression(doEval);
925 condExpr = cp;
926
927 /*
928 * Evaluate the argument using the default function.
929 * This path always treats .if as .ifdef. To get here the character
930 * after .if must have been taken literally, so the argument cannot
931 * be empty - even if it contained a variable expansion.
932 */
933 t = !doEval || if_info->defProc(arglen, arg) != if_info->doNot;
934 free(arg);
935 return t;
936 }
937
938 static Token
CondToken(Boolean doEval)939 CondToken(Boolean doEval)
940 {
941 Token t;
942
943 t = condPushBack;
944 if (t != TOK_NONE) {
945 condPushBack = TOK_NONE;
946 return t;
947 }
948
949 while (*condExpr == ' ' || *condExpr == '\t') {
950 condExpr++;
951 }
952
953 switch (*condExpr) {
954
955 case '(':
956 condExpr++;
957 return TOK_LPAREN;
958
959 case ')':
960 condExpr++;
961 return TOK_RPAREN;
962
963 case '|':
964 if (condExpr[1] == '|') {
965 condExpr++;
966 }
967 condExpr++;
968 return TOK_OR;
969
970 case '&':
971 if (condExpr[1] == '&') {
972 condExpr++;
973 }
974 condExpr++;
975 return TOK_AND;
976
977 case '!':
978 condExpr++;
979 return TOK_NOT;
980
981 case '#':
982 case '\n':
983 case '\0':
984 return TOK_EOF;
985
986 case '"':
987 case '$':
988 return compare_expression(doEval);
989
990 default:
991 return compare_function(doEval);
992 }
993 }
994
995 /*-
996 *-----------------------------------------------------------------------
997 * CondT --
998 * Parse a single term in the expression. This consists of a terminal
999 * symbol or TOK_NOT and a terminal symbol (not including the binary
1000 * operators):
1001 * T -> defined(variable) | make(target) | exists(file) | symbol
1002 * T -> ! T | ( E )
1003 *
1004 * Results:
1005 * TOK_TRUE, TOK_FALSE or TOK_ERROR.
1006 *
1007 * Side Effects:
1008 * Tokens are consumed.
1009 *
1010 *-----------------------------------------------------------------------
1011 */
1012 static Token
CondT(Boolean doEval)1013 CondT(Boolean doEval)
1014 {
1015 Token t;
1016
1017 t = CondToken(doEval);
1018
1019 if (t == TOK_EOF) {
1020 /*
1021 * If we reached the end of the expression, the expression
1022 * is malformed...
1023 */
1024 t = TOK_ERROR;
1025 } else if (t == TOK_LPAREN) {
1026 /*
1027 * T -> ( E )
1028 */
1029 t = CondE(doEval);
1030 if (t != TOK_ERROR) {
1031 if (CondToken(doEval) != TOK_RPAREN) {
1032 t = TOK_ERROR;
1033 }
1034 }
1035 } else if (t == TOK_NOT) {
1036 t = CondT(doEval);
1037 if (t == TOK_TRUE) {
1038 t = TOK_FALSE;
1039 } else if (t == TOK_FALSE) {
1040 t = TOK_TRUE;
1041 }
1042 }
1043 return (t);
1044 }
1045
1046 /*-
1047 *-----------------------------------------------------------------------
1048 * CondF --
1049 * Parse a conjunctive factor (nice name, wot?)
1050 * F -> T && F | T
1051 *
1052 * Results:
1053 * TOK_TRUE, TOK_FALSE or TOK_ERROR
1054 *
1055 * Side Effects:
1056 * Tokens are consumed.
1057 *
1058 *-----------------------------------------------------------------------
1059 */
1060 static Token
CondF(Boolean doEval)1061 CondF(Boolean doEval)
1062 {
1063 Token l, o;
1064
1065 l = CondT(doEval);
1066 if (l != TOK_ERROR) {
1067 o = CondToken(doEval);
1068
1069 if (o == TOK_AND) {
1070 /*
1071 * F -> T && F
1072 *
1073 * If T is TOK_FALSE, the whole thing will be TOK_FALSE, but we have to
1074 * parse the r.h.s. anyway (to throw it away).
1075 * If T is TOK_TRUE, the result is the r.h.s., be it an TOK_ERROR or no.
1076 */
1077 if (l == TOK_TRUE) {
1078 l = CondF(doEval);
1079 } else {
1080 (void)CondF(FALSE);
1081 }
1082 } else {
1083 /*
1084 * F -> T
1085 */
1086 CondPushBack(o);
1087 }
1088 }
1089 return (l);
1090 }
1091
1092 /*-
1093 *-----------------------------------------------------------------------
1094 * CondE --
1095 * Main expression production.
1096 * E -> F || E | F
1097 *
1098 * Results:
1099 * TOK_TRUE, TOK_FALSE or TOK_ERROR.
1100 *
1101 * Side Effects:
1102 * Tokens are, of course, consumed.
1103 *
1104 *-----------------------------------------------------------------------
1105 */
1106 static Token
CondE(Boolean doEval)1107 CondE(Boolean doEval)
1108 {
1109 Token l, o;
1110
1111 l = CondF(doEval);
1112 if (l != TOK_ERROR) {
1113 o = CondToken(doEval);
1114
1115 if (o == TOK_OR) {
1116 /*
1117 * E -> F || E
1118 *
1119 * A similar thing occurs for ||, except that here we make sure
1120 * the l.h.s. is TOK_FALSE before we bother to evaluate the r.h.s.
1121 * Once again, if l is TOK_FALSE, the result is the r.h.s. and once
1122 * again if l is TOK_TRUE, we parse the r.h.s. to throw it away.
1123 */
1124 if (l == TOK_FALSE) {
1125 l = CondE(doEval);
1126 } else {
1127 (void)CondE(FALSE);
1128 }
1129 } else {
1130 /*
1131 * E -> F
1132 */
1133 CondPushBack(o);
1134 }
1135 }
1136 return (l);
1137 }
1138
1139 /*-
1140 *-----------------------------------------------------------------------
1141 * Cond_EvalExpression --
1142 * Evaluate an expression in the passed line. The expression
1143 * consists of &&, ||, !, make(target), defined(variable)
1144 * and parenthetical groupings thereof.
1145 *
1146 * Results:
1147 * COND_PARSE if the condition was valid grammatically
1148 * COND_INVALID if not a valid conditional.
1149 *
1150 * (*value) is set to the boolean value of the condition
1151 *
1152 * Side Effects:
1153 * None.
1154 *
1155 *-----------------------------------------------------------------------
1156 */
1157 int
Cond_EvalExpression(const struct If * info,char * line,Boolean * value,int eprint,Boolean strictLHS)1158 Cond_EvalExpression(const struct If *info, char *line, Boolean *value, int eprint, Boolean strictLHS)
1159 {
1160 static const struct If *dflt_info;
1161 const struct If *sv_if_info = if_info;
1162 char *sv_condExpr = condExpr;
1163 Token sv_condPushBack = condPushBack;
1164 int rval;
1165
1166 lhsStrict = strictLHS;
1167
1168 while (*line == ' ' || *line == '\t')
1169 line++;
1170
1171 if (info == NULL && (info = dflt_info) == NULL) {
1172 /* Scan for the entry for .if - it can't be first */
1173 for (info = ifs; ; info++)
1174 if (info->form[0] == 0)
1175 break;
1176 dflt_info = info;
1177 }
1178 assert(info != NULL);
1179
1180 if_info = info;
1181 condExpr = line;
1182 condPushBack = TOK_NONE;
1183
1184 rval = do_Cond_EvalExpression(value);
1185
1186 if (rval == COND_INVALID && eprint)
1187 Parse_Error(PARSE_FATAL, "Malformed conditional (%s)", line);
1188
1189 if_info = sv_if_info;
1190 condExpr = sv_condExpr;
1191 condPushBack = sv_condPushBack;
1192
1193 return rval;
1194 }
1195
1196 static int
do_Cond_EvalExpression(Boolean * value)1197 do_Cond_EvalExpression(Boolean *value)
1198 {
1199
1200 switch (CondE(TRUE)) {
1201 case TOK_TRUE:
1202 if (CondToken(TRUE) == TOK_EOF) {
1203 *value = TRUE;
1204 return COND_PARSE;
1205 }
1206 break;
1207 case TOK_FALSE:
1208 if (CondToken(TRUE) == TOK_EOF) {
1209 *value = FALSE;
1210 return COND_PARSE;
1211 }
1212 break;
1213 default:
1214 case TOK_ERROR:
1215 break;
1216 }
1217
1218 return COND_INVALID;
1219 }
1220
1221
1222 /*-
1223 *-----------------------------------------------------------------------
1224 * Cond_Eval --
1225 * Evaluate the conditional in the passed line. The line
1226 * looks like this:
1227 * .<cond-type> <expr>
1228 * where <cond-type> is any of if, ifmake, ifnmake, ifdef,
1229 * ifndef, elif, elifmake, elifnmake, elifdef, elifndef
1230 * and <expr> consists of &&, ||, !, make(target), defined(variable)
1231 * and parenthetical groupings thereof.
1232 *
1233 * Input:
1234 * line Line to parse
1235 *
1236 * Results:
1237 * COND_PARSE if should parse lines after the conditional
1238 * COND_SKIP if should skip lines after the conditional
1239 * COND_INVALID if not a valid conditional.
1240 *
1241 * Side Effects:
1242 * None.
1243 *
1244 * Note that the states IF_ACTIVE and ELSE_ACTIVE are only different in order
1245 * to detect splurious .else lines (as are SKIP_TO_ELSE and SKIP_TO_ENDIF)
1246 * otherwise .else could be treated as '.elif 1'.
1247 *
1248 *-----------------------------------------------------------------------
1249 */
1250 int
Cond_Eval(char * line)1251 Cond_Eval(char *line)
1252 {
1253 #define MAXIF 128 /* maximum depth of .if'ing */
1254 #define MAXIF_BUMP 32 /* how much to grow by */
1255 enum if_states {
1256 IF_ACTIVE, /* .if or .elif part active */
1257 ELSE_ACTIVE, /* .else part active */
1258 SEARCH_FOR_ELIF, /* searching for .elif/else to execute */
1259 SKIP_TO_ELSE, /* has been true, but not seen '.else' */
1260 SKIP_TO_ENDIF /* nothing else to execute */
1261 };
1262 static enum if_states *cond_state = NULL;
1263 static unsigned int max_if_depth = MAXIF;
1264
1265 const struct If *ifp;
1266 Boolean isElif;
1267 Boolean value;
1268 int level; /* Level at which to report errors. */
1269 enum if_states state;
1270
1271 level = PARSE_FATAL;
1272 if (!cond_state) {
1273 cond_state = bmake_malloc(max_if_depth * sizeof(*cond_state));
1274 cond_state[0] = IF_ACTIVE;
1275 }
1276 /* skip leading character (the '.') and any whitespace */
1277 for (line++; *line == ' ' || *line == '\t'; line++)
1278 continue;
1279
1280 /* Find what type of if we're dealing with. */
1281 if (line[0] == 'e') {
1282 if (line[1] != 'l') {
1283 if (!istoken(line + 1, "ndif", 4))
1284 return COND_INVALID;
1285 /* End of conditional section */
1286 if (cond_depth == cond_min_depth) {
1287 Parse_Error(level, "if-less endif");
1288 return COND_PARSE;
1289 }
1290 /* Return state for previous conditional */
1291 cond_depth--;
1292 return cond_state[cond_depth] <= ELSE_ACTIVE ? COND_PARSE : COND_SKIP;
1293 }
1294
1295 /* Quite likely this is 'else' or 'elif' */
1296 line += 2;
1297 if (istoken(line, "se", 2)) {
1298 /* It is else... */
1299 if (cond_depth == cond_min_depth) {
1300 Parse_Error(level, "if-less else");
1301 return COND_PARSE;
1302 }
1303
1304 state = cond_state[cond_depth];
1305 switch (state) {
1306 case SEARCH_FOR_ELIF:
1307 state = ELSE_ACTIVE;
1308 break;
1309 case ELSE_ACTIVE:
1310 case SKIP_TO_ENDIF:
1311 Parse_Error(PARSE_WARNING, "extra else");
1312 /* FALLTHROUGH */
1313 default:
1314 case IF_ACTIVE:
1315 case SKIP_TO_ELSE:
1316 state = SKIP_TO_ENDIF;
1317 break;
1318 }
1319 cond_state[cond_depth] = state;
1320 return state <= ELSE_ACTIVE ? COND_PARSE : COND_SKIP;
1321 }
1322 /* Assume for now it is an elif */
1323 isElif = TRUE;
1324 } else
1325 isElif = FALSE;
1326
1327 if (line[0] != 'i' || line[1] != 'f')
1328 /* Not an ifxxx or elifxxx line */
1329 return COND_INVALID;
1330
1331 /*
1332 * Figure out what sort of conditional it is -- what its default
1333 * function is, etc. -- by looking in the table of valid "ifs"
1334 */
1335 line += 2;
1336 for (ifp = ifs; ; ifp++) {
1337 if (ifp->form == NULL)
1338 return COND_INVALID;
1339 if (istoken(ifp->form, line, ifp->formlen)) {
1340 line += ifp->formlen;
1341 break;
1342 }
1343 }
1344
1345 /* Now we know what sort of 'if' it is... */
1346
1347 if (isElif) {
1348 if (cond_depth == cond_min_depth) {
1349 Parse_Error(level, "if-less elif");
1350 return COND_PARSE;
1351 }
1352 state = cond_state[cond_depth];
1353 if (state == SKIP_TO_ENDIF || state == ELSE_ACTIVE) {
1354 Parse_Error(PARSE_WARNING, "extra elif");
1355 cond_state[cond_depth] = SKIP_TO_ENDIF;
1356 return COND_SKIP;
1357 }
1358 if (state != SEARCH_FOR_ELIF) {
1359 /* Either just finished the 'true' block, or already SKIP_TO_ELSE */
1360 cond_state[cond_depth] = SKIP_TO_ELSE;
1361 return COND_SKIP;
1362 }
1363 } else {
1364 /* Normal .if */
1365 if (cond_depth + 1 >= max_if_depth) {
1366 /*
1367 * This is rare, but not impossible.
1368 * In meta mode, dirdeps.mk (only runs at level 0)
1369 * can need more than the default.
1370 */
1371 max_if_depth += MAXIF_BUMP;
1372 cond_state = bmake_realloc(cond_state, max_if_depth *
1373 sizeof(*cond_state));
1374 }
1375 state = cond_state[cond_depth];
1376 cond_depth++;
1377 if (state > ELSE_ACTIVE) {
1378 /* If we aren't parsing the data, treat as always false */
1379 cond_state[cond_depth] = SKIP_TO_ELSE;
1380 return COND_SKIP;
1381 }
1382 }
1383
1384 /* And evaluate the conditional expresssion */
1385 if (Cond_EvalExpression(ifp, line, &value, 1, TRUE) == COND_INVALID) {
1386 /* Syntax error in conditional, error message already output. */
1387 /* Skip everything to matching .endif */
1388 cond_state[cond_depth] = SKIP_TO_ELSE;
1389 return COND_SKIP;
1390 }
1391
1392 if (!value) {
1393 cond_state[cond_depth] = SEARCH_FOR_ELIF;
1394 return COND_SKIP;
1395 }
1396 cond_state[cond_depth] = IF_ACTIVE;
1397 return COND_PARSE;
1398 }
1399
1400
1401
1402 /*-
1403 *-----------------------------------------------------------------------
1404 * Cond_End --
1405 * Make sure everything's clean at the end of a makefile.
1406 *
1407 * Results:
1408 * None.
1409 *
1410 * Side Effects:
1411 * Parse_Error will be called if open conditionals are around.
1412 *
1413 *-----------------------------------------------------------------------
1414 */
1415 void
Cond_restore_depth(unsigned int saved_depth)1416 Cond_restore_depth(unsigned int saved_depth)
1417 {
1418 int open_conds = cond_depth - cond_min_depth;
1419
1420 if (open_conds != 0 || saved_depth > cond_depth) {
1421 Parse_Error(PARSE_FATAL, "%d open conditional%s", open_conds,
1422 open_conds == 1 ? "" : "s");
1423 cond_depth = cond_min_depth;
1424 }
1425
1426 cond_min_depth = saved_depth;
1427 }
1428
1429 unsigned int
Cond_save_depth(void)1430 Cond_save_depth(void)
1431 {
1432 int depth = cond_min_depth;
1433
1434 cond_min_depth = cond_depth;
1435 return depth;
1436 }
1437