Remove __P macros from src/usr.bin and src/usr.sbin.
[dragonfly.git] / usr.bin / make / cond.c
CommitLineData
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1/*
2 * Copyright (c) 1988, 1989, 1990 The Regents of the University of California.
3 * Copyright (c) 1988, 1989 by Adam de Boor
4 * Copyright (c) 1989 by Berkeley Softworks
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. All advertising materials mentioning features or use of this software
19 * must display the following acknowledgement:
20 * This product includes software developed by the University of
21 * California, Berkeley and its contributors.
22 * 4. Neither the name of the University nor the names of its contributors
23 * may be used to endorse or promote products derived from this software
24 * without specific prior written permission.
25 *
26 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
27 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
28 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
29 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
30 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
31 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
32 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
33 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
34 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
35 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
36 * SUCH DAMAGE.
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37 *
38 * @(#)cond.c 8.2 (Berkeley) 1/2/94
39 * $FreeBSD: src/usr.bin/make/cond.c,v 1.12 1999/09/11 13:08:01 hoek Exp $
2d8a3be7 40 * $DragonFly: src/usr.bin/make/cond.c,v 1.3 2003/11/03 19:31:30 eirikn Exp $
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41 */
42
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43/*-
44 * cond.c --
45 * Functions to handle conditionals in a makefile.
46 *
47 * Interface:
48 * Cond_Eval Evaluate the conditional in the passed line.
49 *
50 */
51
52#include <ctype.h>
53#include <math.h>
54#include "make.h"
55#include "hash.h"
56#include "dir.h"
57#include "buf.h"
58
59/*
60 * The parsing of conditional expressions is based on this grammar:
61 * E -> F || E
62 * E -> F
63 * F -> T && F
64 * F -> T
65 * T -> defined(variable)
66 * T -> make(target)
67 * T -> exists(file)
68 * T -> empty(varspec)
69 * T -> target(name)
70 * T -> symbol
71 * T -> $(varspec) op value
72 * T -> $(varspec) == "string"
73 * T -> $(varspec) != "string"
74 * T -> ( E )
75 * T -> ! T
76 * op -> == | != | > | < | >= | <=
77 *
78 * 'symbol' is some other symbol to which the default function (condDefProc)
79 * is applied.
80 *
81 * Tokens are scanned from the 'condExpr' string. The scanner (CondToken)
82 * will return And for '&' and '&&', Or for '|' and '||', Not for '!',
83 * LParen for '(', RParen for ')' and will evaluate the other terminal
84 * symbols, using either the default function or the function given in the
85 * terminal, and return the result as either True or False.
86 *
87 * All Non-Terminal functions (CondE, CondF and CondT) return Err on error.
88 */
89typedef enum {
90 And, Or, Not, True, False, LParen, RParen, EndOfFile, None, Err
91} Token;
92
93/*-
94 * Structures to handle elegantly the different forms of #if's. The
95 * last two fields are stored in condInvert and condDefProc, respectively.
96 */
2d8a3be7
EN
97static void CondPushBack(Token);
98static int CondGetArg(char **, char **, char *, Boolean);
99static Boolean CondDoDefined(int, char *);
100static int CondStrMatch(ClientData, ClientData);
101static Boolean CondDoMake(int, char *);
102static Boolean CondDoExists(int, char *);
103static Boolean CondDoTarget(int, char *);
104static char * CondCvtArg(char *, double *);
105static Token CondToken(Boolean);
106static Token CondT(Boolean);
107static Token CondF(Boolean);
108static Token CondE(Boolean);
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109
110static struct If {
111 char *form; /* Form of if */
112 int formlen; /* Length of form */
113 Boolean doNot; /* TRUE if default function should be negated */
2d8a3be7 114 Boolean (*defProc)(int, char *); /* Default function to apply */
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115} ifs[] = {
116 { "ifdef", 5, FALSE, CondDoDefined },
117 { "ifndef", 6, TRUE, CondDoDefined },
118 { "ifmake", 6, FALSE, CondDoMake },
119 { "ifnmake", 7, TRUE, CondDoMake },
120 { "if", 2, FALSE, CondDoDefined },
121 { NULL, 0, FALSE, NULL }
122};
123
124static Boolean condInvert; /* Invert the default function */
125static Boolean (*condDefProc) /* Default function to apply */
2d8a3be7 126 (int, char *);
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127static char *condExpr; /* The expression to parse */
128static Token condPushBack=None; /* Single push-back token used in
129 * parsing */
130
131#define MAXIF 30 /* greatest depth of #if'ing */
132
133static Boolean condStack[MAXIF]; /* Stack of conditionals's values */
134static int condTop = MAXIF; /* Top-most conditional */
135static int skipIfLevel=0; /* Depth of skipped conditionals */
136static Boolean skipLine = FALSE; /* Whether the parse module is skipping
137 * lines */
138
139/*-
140 *-----------------------------------------------------------------------
141 * CondPushBack --
142 * Push back the most recent token read. We only need one level of
143 * this, so the thing is just stored in 'condPushback'.
144 *
145 * Results:
146 * None.
147 *
148 * Side Effects:
149 * condPushback is overwritten.
150 *
151 *-----------------------------------------------------------------------
152 */
153static void
154CondPushBack (t)
155 Token t; /* Token to push back into the "stream" */
156{
157 condPushBack = t;
158}
159\f
160/*-
161 *-----------------------------------------------------------------------
162 * CondGetArg --
163 * Find the argument of a built-in function.
164 *
165 * Results:
166 * The length of the argument and the address of the argument.
167 *
168 * Side Effects:
169 * The pointer is set to point to the closing parenthesis of the
170 * function call.
171 *
172 *-----------------------------------------------------------------------
173 */
174static int
175CondGetArg (linePtr, argPtr, func, parens)
176 char **linePtr;
177 char **argPtr;
178 char *func;
179 Boolean parens; /* TRUE if arg should be bounded by parens */
180{
181 register char *cp;
182 int argLen;
183 register Buffer buf;
184
185 cp = *linePtr;
186 if (parens) {
187 while (*cp != '(' && *cp != '\0') {
188 cp++;
189 }
190 if (*cp == '(') {
191 cp++;
192 }
193 }
194
195 if (*cp == '\0') {
196 /*
197 * No arguments whatsoever. Because 'make' and 'defined' aren't really
198 * "reserved words", we don't print a message. I think this is better
199 * than hitting the user with a warning message every time s/he uses
200 * the word 'make' or 'defined' at the beginning of a symbol...
201 */
202 *argPtr = cp;
203 return (0);
204 }
205
206 while (*cp == ' ' || *cp == '\t') {
207 cp++;
208 }
209
210 /*
211 * Create a buffer for the argument and start it out at 16 characters
212 * long. Why 16? Why not?
213 */
214 buf = Buf_Init(16);
215
216 while ((strchr(" \t)&|", *cp) == (char *)NULL) && (*cp != '\0')) {
217 if (*cp == '$') {
218 /*
219 * Parse the variable spec and install it as part of the argument
220 * if it's valid. We tell Var_Parse to complain on an undefined
221 * variable, so we don't do it too. Nor do we return an error,
222 * though perhaps we should...
223 */
224 char *cp2;
225 int len;
226 Boolean doFree;
227
228 cp2 = Var_Parse(cp, VAR_CMD, TRUE, &len, &doFree);
229
230 Buf_AddBytes(buf, strlen(cp2), (Byte *)cp2);
231 if (doFree) {
232 free(cp2);
233 }
234 cp += len;
235 } else {
236 Buf_AddByte(buf, (Byte)*cp);
237 cp++;
238 }
239 }
240
241 Buf_AddByte(buf, (Byte)'\0');
242 *argPtr = (char *)Buf_GetAll(buf, &argLen);
243 Buf_Destroy(buf, FALSE);
244
245 while (*cp == ' ' || *cp == '\t') {
246 cp++;
247 }
248 if (parens && *cp != ')') {
249 Parse_Error (PARSE_WARNING, "Missing closing parenthesis for %s()",
250 func);
251 return (0);
252 } else if (parens) {
253 /*
254 * Advance pointer past close parenthesis.
255 */
256 cp++;
257 }
258
259 *linePtr = cp;
260 return (argLen);
261}
262\f
263/*-
264 *-----------------------------------------------------------------------
265 * CondDoDefined --
266 * Handle the 'defined' function for conditionals.
267 *
268 * Results:
269 * TRUE if the given variable is defined.
270 *
271 * Side Effects:
272 * None.
273 *
274 *-----------------------------------------------------------------------
275 */
276static Boolean
277CondDoDefined (argLen, arg)
278 int argLen;
279 char *arg;
280{
281 char savec = arg[argLen];
282 char *p1;
283 Boolean result;
284
285 arg[argLen] = '\0';
286 if (Var_Value (arg, VAR_CMD, &p1) != (char *)NULL) {
287 result = TRUE;
288 } else {
289 result = FALSE;
290 }
291 efree(p1);
292 arg[argLen] = savec;
293 return (result);
294}
295\f
296/*-
297 *-----------------------------------------------------------------------
298 * CondStrMatch --
299 * Front-end for Str_Match so it returns 0 on match and non-zero
300 * on mismatch. Callback function for CondDoMake via Lst_Find
301 *
302 * Results:
303 * 0 if string matches pattern
304 *
305 * Side Effects:
306 * None
307 *
308 *-----------------------------------------------------------------------
309 */
310static int
311CondStrMatch(string, pattern)
312 ClientData string;
313 ClientData pattern;
314{
315 return(!Str_Match((char *) string,(char *) pattern));
316}
317\f
318/*-
319 *-----------------------------------------------------------------------
320 * CondDoMake --
321 * Handle the 'make' function for conditionals.
322 *
323 * Results:
324 * TRUE if the given target is being made.
325 *
326 * Side Effects:
327 * None.
328 *
329 *-----------------------------------------------------------------------
330 */
331static Boolean
332CondDoMake (argLen, arg)
333 int argLen;
334 char *arg;
335{
336 char savec = arg[argLen];
337 Boolean result;
338
339 arg[argLen] = '\0';
340 if (Lst_Find (create, (ClientData)arg, CondStrMatch) == NILLNODE) {
341 result = FALSE;
342 } else {
343 result = TRUE;
344 }
345 arg[argLen] = savec;
346 return (result);
347}
348\f
349/*-
350 *-----------------------------------------------------------------------
351 * CondDoExists --
352 * See if the given file exists.
353 *
354 * Results:
355 * TRUE if the file exists and FALSE if it does not.
356 *
357 * Side Effects:
358 * None.
359 *
360 *-----------------------------------------------------------------------
361 */
362static Boolean
363CondDoExists (argLen, arg)
364 int argLen;
365 char *arg;
366{
367 char savec = arg[argLen];
368 Boolean result;
369 char *path;
370
371 arg[argLen] = '\0';
372 path = Dir_FindFile(arg, dirSearchPath);
373 if (path != (char *)NULL) {
374 result = TRUE;
375 free(path);
376 } else {
377 result = FALSE;
378 }
379 arg[argLen] = savec;
380 return (result);
381}
382\f
383/*-
384 *-----------------------------------------------------------------------
385 * CondDoTarget --
386 * See if the given node exists and is an actual target.
387 *
388 * Results:
389 * TRUE if the node exists as a target and FALSE if it does not.
390 *
391 * Side Effects:
392 * None.
393 *
394 *-----------------------------------------------------------------------
395 */
396static Boolean
397CondDoTarget (argLen, arg)
398 int argLen;
399 char *arg;
400{
401 char savec = arg[argLen];
402 Boolean result;
403 GNode *gn;
404
405 arg[argLen] = '\0';
406 gn = Targ_FindNode(arg, TARG_NOCREATE);
407 if ((gn != NILGNODE) && !OP_NOP(gn->type)) {
408 result = TRUE;
409 } else {
410 result = FALSE;
411 }
412 arg[argLen] = savec;
413 return (result);
414}
415
416\f
417/*-
418 *-----------------------------------------------------------------------
419 * CondCvtArg --
420 * Convert the given number into a double. If the number begins
421 * with 0x, it is interpreted as a hexadecimal integer
422 * and converted to a double from there. All other strings just have
423 * strtod called on them.
424 *
425 * Results:
426 * Sets 'value' to double value of string.
427 * Returns address of the first character after the last valid
428 * character of the converted number.
429 *
430 * Side Effects:
431 * Can change 'value' even if string is not a valid number.
432 *
433 *
434 *-----------------------------------------------------------------------
435 */
436static char *
437CondCvtArg(str, value)
438 register char *str;
439 double *value;
440{
441 if ((*str == '0') && (str[1] == 'x')) {
442 register long i;
443
444 for (str += 2, i = 0; ; str++) {
445 int x;
446 if (isdigit((unsigned char) *str))
447 x = *str - '0';
448 else if (isxdigit((unsigned char) *str))
449 x = 10 + *str - isupper((unsigned char) *str) ? 'A' : 'a';
450 else {
451 *value = (double) i;
452 return str;
453 }
454 i = (i << 4) + x;
455 }
456 }
457 else {
458 char *eptr;
459 *value = strtod(str, &eptr);
460 return eptr;
461 }
462}
463\f
464/*-
465 *-----------------------------------------------------------------------
466 * CondToken --
467 * Return the next token from the input.
468 *
469 * Results:
470 * A Token for the next lexical token in the stream.
471 *
472 * Side Effects:
473 * condPushback will be set back to None if it is used.
474 *
475 *-----------------------------------------------------------------------
476 */
477static Token
478CondToken(doEval)
479 Boolean doEval;
480{
481 Token t;
482
483 if (condPushBack == None) {
484 while (*condExpr == ' ' || *condExpr == '\t') {
485 condExpr++;
486 }
487 switch (*condExpr) {
488 case '(':
489 t = LParen;
490 condExpr++;
491 break;
492 case ')':
493 t = RParen;
494 condExpr++;
495 break;
496 case '|':
497 if (condExpr[1] == '|') {
498 condExpr++;
499 }
500 condExpr++;
501 t = Or;
502 break;
503 case '&':
504 if (condExpr[1] == '&') {
505 condExpr++;
506 }
507 condExpr++;
508 t = And;
509 break;
510 case '!':
511 t = Not;
512 condExpr++;
513 break;
514 case '\n':
515 case '\0':
516 t = EndOfFile;
517 break;
518 case '$': {
519 char *lhs;
520 char *rhs;
521 char *op;
522 int varSpecLen;
523 Boolean doFree;
524
525 /*
526 * Parse the variable spec and skip over it, saving its
527 * value in lhs.
528 */
529 t = Err;
530 lhs = Var_Parse(condExpr, VAR_CMD, doEval,&varSpecLen,&doFree);
531 if (lhs == var_Error) {
532 /*
533 * Even if !doEval, we still report syntax errors, which
534 * is what getting var_Error back with !doEval means.
535 */
536 return(Err);
537 }
538 condExpr += varSpecLen;
539
540 if (!isspace((unsigned char) *condExpr) &&
541 strchr("!=><", *condExpr) == NULL) {
542 Buffer buf;
543 char *cp;
544
545 buf = Buf_Init(0);
546
547 for (cp = lhs; *cp; cp++)
548 Buf_AddByte(buf, (Byte)*cp);
549
550 if (doFree)
551 free(lhs);
552
553 for (;*condExpr && !isspace((unsigned char) *condExpr);
554 condExpr++)
555 Buf_AddByte(buf, (Byte)*condExpr);
556
557 Buf_AddByte(buf, (Byte)'\0');
558 lhs = (char *)Buf_GetAll(buf, &varSpecLen);
559 Buf_Destroy(buf, FALSE);
560
561 doFree = TRUE;
562 }
563
564 /*
565 * Skip whitespace to get to the operator
566 */
567 while (isspace((unsigned char) *condExpr))
568 condExpr++;
569
570 /*
571 * Make sure the operator is a valid one. If it isn't a
572 * known relational operator, pretend we got a
573 * != 0 comparison.
574 */
575 op = condExpr;
576 switch (*condExpr) {
577 case '!':
578 case '=':
579 case '<':
580 case '>':
581 if (condExpr[1] == '=') {
582 condExpr += 2;
583 } else {
584 condExpr += 1;
585 }
586 break;
587 default:
588 op = "!=";
589 rhs = "0";
590
591 goto do_compare;
592 }
593 while (isspace((unsigned char) *condExpr)) {
594 condExpr++;
595 }
596 if (*condExpr == '\0') {
597 Parse_Error(PARSE_WARNING,
598 "Missing right-hand-side of operator");
599 goto error;
600 }
601 rhs = condExpr;
602do_compare:
603 if (*rhs == '"') {
604 /*
605 * Doing a string comparison. Only allow == and != for
606 * operators.
607 */
608 char *string;
609 char *cp, *cp2;
610 int qt;
611 Buffer buf;
612
613do_string_compare:
614 if (((*op != '!') && (*op != '=')) || (op[1] != '=')) {
615 Parse_Error(PARSE_WARNING,
616 "String comparison operator should be either == or !=");
617 goto error;
618 }
619
620 buf = Buf_Init(0);
621 qt = *rhs == '"' ? 1 : 0;
622
623 for (cp = &rhs[qt];
624 ((qt && (*cp != '"')) ||
625 (!qt && strchr(" \t)", *cp) == NULL)) &&
626 (*cp != '\0'); cp++) {
627 if ((*cp == '\\') && (cp[1] != '\0')) {
628 /*
629 * Backslash escapes things -- skip over next
630 * character, if it exists.
631 */
632 cp++;
633 Buf_AddByte(buf, (Byte)*cp);
634 } else if (*cp == '$') {
635 int len;
636 Boolean freeIt;
637
638 cp2 = Var_Parse(cp, VAR_CMD, doEval,&len, &freeIt);
639 if (cp2 != var_Error) {
640 Buf_AddBytes(buf, strlen(cp2), (Byte *)cp2);
641 if (freeIt) {
642 free(cp2);
643 }
644 cp += len - 1;
645 } else {
646 Buf_AddByte(buf, (Byte)*cp);
647 }
648 } else {
649 Buf_AddByte(buf, (Byte)*cp);
650 }
651 }
652
653 Buf_AddByte(buf, (Byte)0);
654
655 string = (char *)Buf_GetAll(buf, (int *)0);
656 Buf_Destroy(buf, FALSE);
657
658 if (DEBUG(COND)) {
659 printf("lhs = \"%s\", rhs = \"%s\", op = %.2s\n",
660 lhs, string, op);
661 }
662 /*
663 * Null-terminate rhs and perform the comparison.
664 * t is set to the result.
665 */
666 if (*op == '=') {
667 t = strcmp(lhs, string) ? False : True;
668 } else {
669 t = strcmp(lhs, string) ? True : False;
670 }
671 free(string);
672 if (rhs == condExpr) {
673 if (!qt && *cp == ')')
674 condExpr = cp;
675 else
676 condExpr = cp + 1;
677 }
678 } else {
679 /*
680 * rhs is either a float or an integer. Convert both the
681 * lhs and the rhs to a double and compare the two.
682 */
683 double left, right;
684 char *string;
685
686 if (*CondCvtArg(lhs, &left) != '\0')
687 goto do_string_compare;
688 if (*rhs == '$') {
689 int len;
690 Boolean freeIt;
691
692 string = Var_Parse(rhs, VAR_CMD, doEval,&len,&freeIt);
693 if (string == var_Error) {
694 right = 0.0;
695 } else {
696 if (*CondCvtArg(string, &right) != '\0') {
697 if (freeIt)
698 free(string);
699 goto do_string_compare;
700 }
701 if (freeIt)
702 free(string);
703 if (rhs == condExpr)
704 condExpr += len;
705 }
706 } else {
707 char *c = CondCvtArg(rhs, &right);
708 if (*c != '\0' && !isspace(*c))
709 goto do_string_compare;
710 if (rhs == condExpr) {
711 /*
712 * Skip over the right-hand side
713 */
714 while(!isspace((unsigned char) *condExpr) &&
715 (*condExpr != '\0')) {
716 condExpr++;
717 }
718 }
719 }
720
721 if (DEBUG(COND)) {
722 printf("left = %f, right = %f, op = %.2s\n", left,
723 right, op);
724 }
725 switch(op[0]) {
726 case '!':
727 if (op[1] != '=') {
728 Parse_Error(PARSE_WARNING,
729 "Unknown operator");
730 goto error;
731 }
732 t = (left != right ? True : False);
733 break;
734 case '=':
735 if (op[1] != '=') {
736 Parse_Error(PARSE_WARNING,
737 "Unknown operator");
738 goto error;
739 }
740 t = (left == right ? True : False);
741 break;
742 case '<':
743 if (op[1] == '=') {
744 t = (left <= right ? True : False);
745 } else {
746 t = (left < right ? True : False);
747 }
748 break;
749 case '>':
750 if (op[1] == '=') {
751 t = (left >= right ? True : False);
752 } else {
753 t = (left > right ? True : False);
754 }
755 break;
756 }
757 }
758error:
759 if (doFree)
760 free(lhs);
761 break;
762 }
763 default: {
2d8a3be7 764 Boolean (*evalProc)(int, char *);
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765 Boolean invert = FALSE;
766 char *arg;
767 int arglen;
768
769 if (strncmp (condExpr, "defined", 7) == 0) {
770 /*
771 * Use CondDoDefined to evaluate the argument and
772 * CondGetArg to extract the argument from the 'function
773 * call'.
774 */
775 evalProc = CondDoDefined;
776 condExpr += 7;
777 arglen = CondGetArg (&condExpr, &arg, "defined", TRUE);
778 if (arglen == 0) {
779 condExpr -= 7;
780 goto use_default;
781 }
782 } else if (strncmp (condExpr, "make", 4) == 0) {
783 /*
784 * Use CondDoMake to evaluate the argument and
785 * CondGetArg to extract the argument from the 'function
786 * call'.
787 */
788 evalProc = CondDoMake;
789 condExpr += 4;
790 arglen = CondGetArg (&condExpr, &arg, "make", TRUE);
791 if (arglen == 0) {
792 condExpr -= 4;
793 goto use_default;
794 }
795 } else if (strncmp (condExpr, "exists", 6) == 0) {
796 /*
797 * Use CondDoExists to evaluate the argument and
798 * CondGetArg to extract the argument from the
799 * 'function call'.
800 */
801 evalProc = CondDoExists;
802 condExpr += 6;
803 arglen = CondGetArg(&condExpr, &arg, "exists", TRUE);
804 if (arglen == 0) {
805 condExpr -= 6;
806 goto use_default;
807 }
808 } else if (strncmp(condExpr, "empty", 5) == 0) {
809 /*
810 * Use Var_Parse to parse the spec in parens and return
811 * True if the resulting string is empty.
812 */
813 int length;
814 Boolean doFree;
815 char *val;
816
817 condExpr += 5;
818
819 for (arglen = 0;
820 condExpr[arglen] != '(' && condExpr[arglen] != '\0';
821 arglen += 1)
822 continue;
823
824 if (condExpr[arglen] != '\0') {
825 val = Var_Parse(&condExpr[arglen - 1], VAR_CMD,
826 doEval, &length, &doFree);
827 if (val == var_Error) {
828 t = Err;
829 } else {
830 /*
831 * A variable is empty when it just contains
832 * spaces... 4/15/92, christos
833 */
834 char *p;
835 for (p = val; *p && isspace((unsigned char)*p); p++)
836 continue;
837 t = (*p == '\0') ? True : False;
838 }
839 if (doFree) {
840 free(val);
841 }
842 /*
843 * Advance condExpr to beyond the closing ). Note that
844 * we subtract one from arglen + length b/c length
845 * is calculated from condExpr[arglen - 1].
846 */
847 condExpr += arglen + length - 1;
848 } else {
849 condExpr -= 5;
850 goto use_default;
851 }
852 break;
853 } else if (strncmp (condExpr, "target", 6) == 0) {
854 /*
855 * Use CondDoTarget to evaluate the argument and
856 * CondGetArg to extract the argument from the
857 * 'function call'.
858 */
859 evalProc = CondDoTarget;
860 condExpr += 6;
861 arglen = CondGetArg(&condExpr, &arg, "target", TRUE);
862 if (arglen == 0) {
863 condExpr -= 6;
864 goto use_default;
865 }
866 } else {
867 /*
868 * The symbol is itself the argument to the default
869 * function. We advance condExpr to the end of the symbol
870 * by hand (the next whitespace, closing paren or
871 * binary operator) and set to invert the evaluation
872 * function if condInvert is TRUE.
873 */
874 use_default:
875 invert = condInvert;
876 evalProc = condDefProc;
877 arglen = CondGetArg(&condExpr, &arg, "", FALSE);
878 }
879
880 /*
881 * Evaluate the argument using the set function. If invert
882 * is TRUE, we invert the sense of the function.
883 */
884 t = (!doEval || (* evalProc) (arglen, arg) ?
885 (invert ? False : True) :
886 (invert ? True : False));
887 free(arg);
888 break;
889 }
890 }
891 } else {
892 t = condPushBack;
893 condPushBack = None;
894 }
895 return (t);
896}
897\f
898/*-
899 *-----------------------------------------------------------------------
900 * CondT --
901 * Parse a single term in the expression. This consists of a terminal
902 * symbol or Not and a terminal symbol (not including the binary
903 * operators):
904 * T -> defined(variable) | make(target) | exists(file) | symbol
905 * T -> ! T | ( E )
906 *
907 * Results:
908 * True, False or Err.
909 *
910 * Side Effects:
911 * Tokens are consumed.
912 *
913 *-----------------------------------------------------------------------
914 */
915static Token
916CondT(doEval)
917 Boolean doEval;
918{
919 Token t;
920
921 t = CondToken(doEval);
922
923 if (t == EndOfFile) {
924 /*
925 * If we reached the end of the expression, the expression
926 * is malformed...
927 */
928 t = Err;
929 } else if (t == LParen) {
930 /*
931 * T -> ( E )
932 */
933 t = CondE(doEval);
934 if (t != Err) {
935 if (CondToken(doEval) != RParen) {
936 t = Err;
937 }
938 }
939 } else if (t == Not) {
940 t = CondT(doEval);
941 if (t == True) {
942 t = False;
943 } else if (t == False) {
944 t = True;
945 }
946 }
947 return (t);
948}
949\f
950/*-
951 *-----------------------------------------------------------------------
952 * CondF --
953 * Parse a conjunctive factor (nice name, wot?)
954 * F -> T && F | T
955 *
956 * Results:
957 * True, False or Err
958 *
959 * Side Effects:
960 * Tokens are consumed.
961 *
962 *-----------------------------------------------------------------------
963 */
964static Token
965CondF(doEval)
966 Boolean doEval;
967{
968 Token l, o;
969
970 l = CondT(doEval);
971 if (l != Err) {
972 o = CondToken(doEval);
973
974 if (o == And) {
975 /*
976 * F -> T && F
977 *
978 * If T is False, the whole thing will be False, but we have to
979 * parse the r.h.s. anyway (to throw it away).
980 * If T is True, the result is the r.h.s., be it an Err or no.
981 */
982 if (l == True) {
983 l = CondF(doEval);
984 } else {
985 (void) CondF(FALSE);
986 }
987 } else {
988 /*
989 * F -> T
990 */
991 CondPushBack (o);
992 }
993 }
994 return (l);
995}
996\f
997/*-
998 *-----------------------------------------------------------------------
999 * CondE --
1000 * Main expression production.
1001 * E -> F || E | F
1002 *
1003 * Results:
1004 * True, False or Err.
1005 *
1006 * Side Effects:
1007 * Tokens are, of course, consumed.
1008 *
1009 *-----------------------------------------------------------------------
1010 */
1011static Token
1012CondE(doEval)
1013 Boolean doEval;
1014{
1015 Token l, o;
1016
1017 l = CondF(doEval);
1018 if (l != Err) {
1019 o = CondToken(doEval);
1020
1021 if (o == Or) {
1022 /*
1023 * E -> F || E
1024 *
1025 * A similar thing occurs for ||, except that here we make sure
1026 * the l.h.s. is False before we bother to evaluate the r.h.s.
1027 * Once again, if l is False, the result is the r.h.s. and once
1028 * again if l is True, we parse the r.h.s. to throw it away.
1029 */
1030 if (l == False) {
1031 l = CondE(doEval);
1032 } else {
1033 (void) CondE(FALSE);
1034 }
1035 } else {
1036 /*
1037 * E -> F
1038 */
1039 CondPushBack (o);
1040 }
1041 }
1042 return (l);
1043}
1044\f
1045/*-
1046 *-----------------------------------------------------------------------
1047 * Cond_Eval --
1048 * Evaluate the conditional in the passed line. The line
1049 * looks like this:
1050 * #<cond-type> <expr>
1051 * where <cond-type> is any of if, ifmake, ifnmake, ifdef,
1052 * ifndef, elif, elifmake, elifnmake, elifdef, elifndef
1053 * and <expr> consists of &&, ||, !, make(target), defined(variable)
1054 * and parenthetical groupings thereof.
1055 *
1056 * Results:
1057 * COND_PARSE if should parse lines after the conditional
1058 * COND_SKIP if should skip lines after the conditional
1059 * COND_INVALID if not a valid conditional.
1060 *
1061 * Side Effects:
1062 * None.
1063 *
1064 *-----------------------------------------------------------------------
1065 */
1066int
1067Cond_Eval (line)
1068 char *line; /* Line to parse */
1069{
1070 struct If *ifp;
1071 Boolean isElse;
1072 Boolean value = FALSE;
1073 int level; /* Level at which to report errors. */
1074
1075 level = PARSE_FATAL;
1076
1077 for (line++; *line == ' ' || *line == '\t'; line++) {
1078 continue;
1079 }
1080
1081 /*
1082 * Find what type of if we're dealing with. The result is left
1083 * in ifp and isElse is set TRUE if it's an elif line.
1084 */
1085 if (line[0] == 'e' && line[1] == 'l') {
1086 line += 2;
1087 isElse = TRUE;
1088 } else if (strncmp (line, "endif", 5) == 0) {
1089 /*
1090 * End of a conditional section. If skipIfLevel is non-zero, that
1091 * conditional was skipped, so lines following it should also be
1092 * skipped. Hence, we return COND_SKIP. Otherwise, the conditional
1093 * was read so succeeding lines should be parsed (think about it...)
1094 * so we return COND_PARSE, unless this endif isn't paired with
1095 * a decent if.
1096 */
1097 if (skipIfLevel != 0) {
1098 skipIfLevel -= 1;
1099 return (COND_SKIP);
1100 } else {
1101 if (condTop == MAXIF) {
1102 Parse_Error (level, "if-less endif");
1103 return (COND_INVALID);
1104 } else {
1105 skipLine = FALSE;
1106 condTop += 1;
1107 return (COND_PARSE);
1108 }
1109 }
1110 } else {
1111 isElse = FALSE;
1112 }
1113
1114 /*
1115 * Figure out what sort of conditional it is -- what its default
1116 * function is, etc. -- by looking in the table of valid "ifs"
1117 */
1118 for (ifp = ifs; ifp->form != (char *)0; ifp++) {
1119 if (strncmp (ifp->form, line, ifp->formlen) == 0) {
1120 break;
1121 }
1122 }
1123
1124 if (ifp->form == (char *) 0) {
1125 /*
1126 * Nothing fit. If the first word on the line is actually
1127 * "else", it's a valid conditional whose value is the inverse
1128 * of the previous if we parsed.
1129 */
1130 if (isElse && (line[0] == 's') && (line[1] == 'e')) {
1131 if (condTop == MAXIF) {
1132 Parse_Error (level, "if-less else");
1133 return (COND_INVALID);
1134 } else if (skipIfLevel == 0) {
1135 value = !condStack[condTop];
1136 } else {
1137 return (COND_SKIP);
1138 }
1139 } else {
1140 /*
1141 * Not a valid conditional type. No error...
1142 */
1143 return (COND_INVALID);
1144 }
1145 } else {
1146 if (isElse) {
1147 if (condTop == MAXIF) {
1148 Parse_Error (level, "if-less elif");
1149 return (COND_INVALID);
1150 } else if (skipIfLevel != 0) {
1151 /*
1152 * If skipping this conditional, just ignore the whole thing.
1153 * If we don't, the user might be employing a variable that's
1154 * undefined, for which there's an enclosing ifdef that
1155 * we're skipping...
1156 */
1157 return(COND_SKIP);
1158 }
1159 } else if (skipLine) {
1160 /*
1161 * Don't even try to evaluate a conditional that's not an else if
1162 * we're skipping things...
1163 */
1164 skipIfLevel += 1;
1165 return(COND_SKIP);
1166 }
1167
1168 /*
1169 * Initialize file-global variables for parsing
1170 */
1171 condDefProc = ifp->defProc;
1172 condInvert = ifp->doNot;
1173
1174 line += ifp->formlen;
1175
1176 while (*line == ' ' || *line == '\t') {
1177 line++;
1178 }
1179
1180 condExpr = line;
1181 condPushBack = None;
1182
1183 switch (CondE(TRUE)) {
1184 case True:
1185 if (CondToken(TRUE) == EndOfFile) {
1186 value = TRUE;
1187 break;
1188 }
1189 goto err;
1190 /*FALLTHRU*/
1191 case False:
1192 if (CondToken(TRUE) == EndOfFile) {
1193 value = FALSE;
1194 break;
1195 }
1196 /*FALLTHRU*/
1197 case Err:
1198 err:
1199 Parse_Error (level, "Malformed conditional (%s)",
1200 line);
1201 return (COND_INVALID);
1202 default:
1203 break;
1204 }
1205 }
1206 if (!isElse) {
1207 condTop -= 1;
1208 } else if ((skipIfLevel != 0) || condStack[condTop]) {
1209 /*
1210 * If this is an else-type conditional, it should only take effect
1211 * if its corresponding if was evaluated and FALSE. If its if was
1212 * TRUE or skipped, we return COND_SKIP (and start skipping in case
1213 * we weren't already), leaving the stack unmolested so later elif's
1214 * don't screw up...
1215 */
1216 skipLine = TRUE;
1217 return (COND_SKIP);
1218 }
1219
1220 if (condTop < 0) {
1221 /*
1222 * This is the one case where we can definitely proclaim a fatal
1223 * error. If we don't, we're hosed.
1224 */
1225 Parse_Error (PARSE_FATAL, "Too many nested if's. %d max.", MAXIF);
1226 return (COND_INVALID);
1227 } else {
1228 condStack[condTop] = value;
1229 skipLine = !value;
1230 return (value ? COND_PARSE : COND_SKIP);
1231 }
1232}
1233\f
1234/*-
1235 *-----------------------------------------------------------------------
1236 * Cond_End --
1237 * Make sure everything's clean at the end of a makefile.
1238 *
1239 * Results:
1240 * None.
1241 *
1242 * Side Effects:
1243 * Parse_Error will be called if open conditionals are around.
1244 *
1245 *-----------------------------------------------------------------------
1246 */
1247void
1248Cond_End()
1249{
1250 if (condTop != MAXIF) {
1251 Parse_Error(PARSE_FATAL, "%d open conditional%s", MAXIF-condTop,
1252 MAXIF-condTop == 1 ? "" : "s");
1253 }
1254 condTop = MAXIF;
1255}