expreval.c@ 2074

Last change on this file since 2074 was 2022, checked in by bird, 16 years ago
exprval.c: fixed bug parsing unqoted variable references ($(VAR) == $(VAR)). Converted ifcond testcases to the GNU Make tests and supplemented it with tests for this bug.
Property svn:eol-style set to `native` Property svn:keywords set to `Author Date Id Revision`
File size: 52.5 KB

Line
1	#ifdef CONFIG_WITH_IF_CONDITIONALS
2	/* $Id: expreval.c 2022 2008-11-02 02:15:00Z bird $ */
3	/** @file
4	* expreval - Expressions evaluator, C / BSD make / nmake style.
5	*/
6
7	/*
8	* Copyright (c) 2008 knut st. osmundsen <[email protected]>
9	*
10	* This file is part of kBuild.
11	*
12	* kBuild is free software; you can redistribute it and/or modify
13	* it under the terms of the GNU General Public License as published by
14	* the Free Software Foundation; either version 3 of the License, or
15	* (at your option) any later version.
16	*
17	* kBuild is distributed in the hope that it will be useful,
18	* but WITHOUT ANY WARRANTY; without even the implied warranty of
19	* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
20	* GNU General Public License for more details.
21	*
22	* You should have received a copy of the GNU General Public License
23	* along with kBuild. If not, see <http://www.gnu.org/licenses/>
24	*
25	*/
26
27	/*******************************************************************************
28	* Header Files *
29	*******************************************************************************/
30	#include "make.h"
31	#include <assert.h>
32
33	#include <glob.h>
34
35	#include "dep.h"
36	#include "filedef.h"
37	#include "job.h"
38	#include "commands.h"
39	#include "variable.h"
40	#include "rule.h"
41	#include "debug.h"
42	#include "hash.h"
43	#include <ctype.h>
44	#ifndef _MSC_VER
45	# include <stdint.h>
46	#endif
47	#include <stdarg.h>
48
49
50	/*******************************************************************************
51	* Defined Constants And Macros *
52	*******************************************************************************/
53	/** The max length of a string representation of a number. */
54	#define EXPR_NUM_LEN ((sizeof("-9223372036854775802") + 4) & ~3)
55
56	/** The max operator stack depth. */
57	#define EXPR_MAX_OPERATORS 72
58	/** The max operand depth. */
59	#define EXPR_MAX_OPERANDS 128
60
61
62	/*******************************************************************************
63	* Structures and Typedefs *
64	*******************************************************************************/
65	/** The 64-bit signed integer type we're using. */
66	#ifdef _MSC_VER
67	typedef __int64 EXPRINT64;
68	#else
69	# include <stdint.h>
70	typedef int64_t EXPRINT64;
71	#endif
72
73	/** Pointer to a evaluator instance. */
74	typedef struct EXPR *PEXPR;
75
76
77	/**
78	* Operand variable type.
79	*/
80	typedef enum
81	{
82	/** Invalid zero entry. */
83	kExprVar_Invalid = 0,
84	/** A number. */
85	kExprVar_Num,
86	/** A string in need of expanding (perhaps). */
87	kExprVar_String,
88	/** A simple string that doesn't need expanding. */
89	kExprVar_SimpleString,
90	/** A quoted string in need of expanding (perhaps). */
91	kExprVar_QuotedString,
92	/** A simple quoted string that doesn't need expanding. */
93	kExprVar_QuotedSimpleString,
94	/** The end of the valid variable types. */
95	kExprVar_End
96	} EXPRVARTYPE;
97
98	/**
99	* Operand variable.
100	*/
101	typedef struct
102	{
103	/** The variable type. */
104	EXPRVARTYPE enmType;
105	/** The variable. */
106	union
107	{
108	/** Pointer to the string. */
109	char *psz;
110	/** The variable. */
111	EXPRINT64 i;
112	} uVal;
113	} EXPRVAR;
114	/** Pointer to a operand variable. */
115	typedef EXPRVAR *PEXPRVAR;
116	/** Pointer to a const operand variable. */
117	typedef EXPRVAR const *PCEXPRVAR;
118
119	/**
120	* Operator return statuses.
121	*/
122	typedef enum
123	{
124	kExprRet_Error = -1,
125	kExprRet_Ok = 0,
126	kExprRet_Operator,
127	kExprRet_Operand,
128	kExprRet_EndOfExpr,
129	kExprRet_End
130	} EXPRRET;
131
132	/**
133	* Operator.
134	*/
135	typedef struct
136	{
137	/** The operator. */
138	char szOp[11];
139	/** The length of the operator string. */
140	char cchOp;
141	/** The pair operator.
142	* This is used with '(' and '?'. */
143	char chPair;
144	/** The precedence. Higher means higher. */
145	char iPrecedence;
146	/** The number of arguments it takes. */
147	signed char cArgs;
148	/** Pointer to the method implementing the operator. */
149	EXPRRET (*pfn)(PEXPR pThis);
150	} EXPROP;
151	/** Pointer to a const operator. */
152	typedef EXPROP const *PCEXPROP;
153
154	/**
155	* Expression evaluator instance.
156	*/
157	typedef struct EXPR
158	{
159	/** The full expression. */
160	const char *pszExpr;
161	/** The current location. */
162	const char *psz;
163	/** The current file location, used for errors. */
164	const struct floc *pFileLoc;
165	/** Pending binary operator. */
166	PCEXPROP pPending;
167	/** Top of the operator stack. */
168	int iOp;
169	/** Top of the operand stack. */
170	int iVar;
171	/** The operator stack. */
172	PCEXPROP apOps[EXPR_MAX_OPERATORS];
173	/** The operand stack. */
174	EXPRVAR aVars[EXPR_MAX_OPERANDS];
175	} EXPR;
176
177
178	/*******************************************************************************
179	* Global Variables *
180	*******************************************************************************/
181	/** Operator start character map.
182	* This indicates which characters that are starting operators and which aren't. */
183	static char g_auchOpStartCharMap[256];
184	/** Whether we've initialized the map. */
185	static int g_fExprInitializedMap = 0;
186
187
188	/*******************************************************************************
189	* Internal Functions *
190	*******************************************************************************/
191	static void expr_unget_op(PEXPR pThis);
192	static EXPRRET expr_get_binary_or_eoe_or_rparen(PEXPR pThis);
193
194
195
196
197	/**
198	* Displays an error message.
199	*
200	* The total string length must not exceed 256 bytes.
201	*
202	* @param pThis The evaluator instance.
203	* @param pszError The message format string.
204	* @param ... The message format args.
205	*/
206	static void expr_error(PEXPR pThis, const char *pszError, ...)
207	{
208	char szTmp[256];
209	va_list va;
210
211	va_start(va, pszError);
212	vsprintf(szTmp, pszError, va);
213	va_end(va);
214
215	fatal(pThis->pFileLoc, "%s", szTmp);
216	}
217
218
219	/**
220	* Converts a number to a string.
221	*
222	* @returns pszDst.
223	* @param pszDst The string buffer to write into. Assumes length of EXPR_NUM_LEN.
224	* @param iSrc The number to convert.
225	*/
226	static char expr_num_to_string(char pszDst, EXPRINT64 iSrc)
227	{
228	static const char s_szDigits[17] = "0123456789abcdef";
229	char szTmp[EXPR_NUM_LEN];
230	char *psz = &szTmp[EXPR_NUM_LEN - 1];
231	int fNegative;
232
233	fNegative = iSrc < 0;
234	if (fNegative)
235	{
236	/** @todo this isn't right for INT64_MIN. */
237	iSrc = -iSrc;
238	}
239
240	*psz = '\0';
241	do
242	{
243	#if 0
244	*--psz = s_szDigits[iSrc & 0xf];
245	iSrc >>= 4;
246	#else
247	*--psz = s_szDigits[iSrc % 10];
248	iSrc /= 10;
249	#endif
250	} while (iSrc);
251
252	#if 0
253	*--psz = 'x';
254	*--psz = '0';
255	#endif
256
257	if (fNegative)
258	*--psz = '-';
259
260	/* copy it into the output buffer. */
261	return (char *)memcpy(pszDst, psz, &szTmp[EXPR_NUM_LEN] - psz);
262	}
263
264
265	/**
266	* Attempts to convert a (simple) string into a number.
267	*
268	* @returns status code.
269	* @param pThis The evaluator instance. This is optional when fQuiet is true.
270	* @param piSrc Where to store the numeric value on success.
271	* @param pszSrc The string to try convert.
272	* @param fQuiet Whether we should be quiet or grumpy on failure.
273	*/
274	static EXPRRET expr_string_to_num(PEXPR pThis, EXPRINT64 piDst, const char pszSrc, int fQuiet)
275	{
276	EXPRRET rc = kExprRet_Ok;
277	char const *psz = pszSrc;
278	EXPRINT64 i;
279	unsigned uBase;
280	int fNegative;
281
282
283	/*
284	* Skip blanks.
285	*/
286	while (isblank(*psz))
287	psz++;
288
289	/*
290	* Check for '-'.
291	*
292	* At this point we will not need to deal with operators, this is
293	* just an indicator of negative numbers. If some operator ends up
294	* here it's because it came from a string expansion and thus shall
295	* not be interpreted. If this turns out to be an stupid restriction
296	* it can be fixed, but for now it stays like this.
297	*/
298	fNegative = *psz == '-';
299	if (fNegative)
300	psz++;
301
302	/*
303	* Determin base .
304	* .
305	* Recognize some exsotic prefixes here in addition to the two standard ones.
306	*/
307	if (*psz != '0' \|\| psz[1] == '\0' \|\| isblank((unsigned int)psz[1]))
308	uBase = 10;
309	else if (psz[1] == 'x' \|\| psz[1] == 'X')
310	{
311	uBase = 16;
312	psz += 2;
313	}
314	else if (psz[1] == 'b' \|\| psz[1] == 'B')
315	{
316	uBase = 2;
317	psz += 2;
318	}
319	else if (psz[1] == 'd' \|\| psz[1] == 'D')
320	{
321	uBase = 10;
322	psz += 2;
323	}
324	else if (psz[1] == 'o' \|\| psz[1] == 'O')
325	{
326	uBase = 8;
327	psz += 2;
328	}
329	else if (isdigit(psz[1]) && psz[1] != '9' && psz[1] != '8')
330	{
331	uBase = 8;
332	psz++;
333	}
334	else
335	uBase = 10;
336
337	/*
338	* Convert until we hit a non-digit.
339	*/
340	i = 0;
341	for (;;)
342	{
343	unsigned iDigit;
344	int ch = *psz;
345	switch (ch)
346	{
347	case '0': iDigit = 0; break;
348	case '1': iDigit = 1; break;
349	case '2': iDigit = 2; break;
350	case '3': iDigit = 3; break;
351	case '4': iDigit = 4; break;
352	case '5': iDigit = 5; break;
353	case '6': iDigit = 6; break;
354	case '7': iDigit = 7; break;
355	case '8': iDigit = 8; break;
356	case '9': iDigit = 9; break;
357	case 'a':
358	case 'A': iDigit = 10; break;
359	case 'b':
360	case 'B': iDigit = 11; break;
361	case 'c':
362	case 'C': iDigit = 12; break;
363	case 'd':
364	case 'D': iDigit = 13; break;
365	case 'e':
366	case 'E': iDigit = 14; break;
367	case 'f':
368	case 'F': iDigit = 15; break;
369
370	default:
371	/* is the rest white space? */
372	while (isspace((unsigned int)*psz))
373	psz++;
374	if (*psz != '\0')
375	{
376	iDigit = uBase;
377	break;
378	}
379	/* fall thru */
380
381	case '\0':
382	if (fNegative)
383	i = -i;
384	*piDst = i;
385	return rc;
386	}
387	if (iDigit >= uBase)
388	{
389	if (fNegative)
390	i = -i;
391	*piDst = i;
392	if (!fQuiet)
393	expr_error(pThis, "Invalid a number \"%.80s\"", pszSrc);
394	return kExprRet_Error;
395	}
396
397	/* add the digit and advance */
398	i *= uBase;
399	i += iDigit;
400	psz++;
401	}
402	/* not reached */
403	}
404
405
406	/**
407	* Checks if the variable is a string or not.
408	*
409	* @returns 1 if it's a string, 0 otherwise.
410	* @param pVar The variable.
411	*/
412	static int expr_var_is_string(PCEXPRVAR pVar)
413	{
414	return pVar->enmType >= kExprVar_String;
415	}
416
417
418	/**
419	* Checks if the variable contains a string that was quoted
420	* in the expression.
421	*
422	* @returns 1 if if was a quoted string, otherwise 0.
423	* @param pVar The variable.
424	*/
425	static int expr_var_was_quoted(PCEXPRVAR pVar)
426	{
427	return pVar->enmType >= kExprVar_QuotedString;
428	}
429
430
431	/**
432	* Deletes a variable.
433	*
434	* @param pVar The variable.
435	*/
436	static void expr_var_delete(PEXPRVAR pVar)
437	{
438	if (expr_var_is_string(pVar))
439	{
440	free(pVar->uVal.psz);
441	pVar->uVal.psz = NULL;
442	}
443	pVar->enmType = kExprVar_Invalid;
444	}
445
446
447	/**
448	* Initializes a new variables with a sub-string value.
449	*
450	* @param pVar The new variable.
451	* @param psz The start of the string value.
452	* @param cch The number of chars to copy.
453	* @param enmType The string type.
454	*/
455	static void expr_var_init_substring(PEXPRVAR pVar, const char *psz, size_t cch, EXPRVARTYPE enmType)
456	{
457	/* convert string needing expanding into simple ones if possible. */
458	if ( enmType == kExprVar_String
459	&& !memchr(psz, '$', cch))
460	enmType = kExprVar_SimpleString;
461	else if ( enmType == kExprVar_QuotedString
462	&& !memchr(psz, '$', cch))
463	enmType = kExprVar_QuotedSimpleString;
464
465	pVar->enmType = enmType;
466	pVar->uVal.psz = xmalloc(cch + 1);
467	memcpy(pVar->uVal.psz, psz, cch);
468	pVar->uVal.psz[cch] = '\0';
469	}
470
471
472	#if 0 /* unused */
473	/**
474	* Initializes a new variables with a string value.
475	*
476	* @param pVar The new variable.
477	* @param psz The string value.
478	* @param enmType The string type.
479	*/
480	static void expr_var_init_string(PEXPRVAR pVar, const char *psz, EXPRVARTYPE enmType)
481	{
482	expr_var_init_substring(pVar, psz, strlen(psz), enmType);
483	}
484
485
486	/**
487	* Assigns a sub-string value to a variable.
488	*
489	* @param pVar The new variable.
490	* @param psz The start of the string value.
491	* @param cch The number of chars to copy.
492	* @param enmType The string type.
493	*/
494	static void expr_var_assign_substring(PEXPRVAR pVar, const char *psz, size_t cch, EXPRVARTYPE enmType)
495	{
496	expr_var_delete(pVar);
497	expr_var_init_substring(pVar, psz, cch, enmType);
498	}
499
500
501	/**
502	* Assignes a string value to a variable.
503	*
504	* @param pVar The variable.
505	* @param psz The string value.
506	* @param enmType The string type.
507	*/
508	static void expr_var_assign_string(PEXPRVAR pVar, const char *psz, EXPRVARTYPE enmType)
509	{
510	expr_var_delete(pVar);
511	expr_var_init_string(pVar, psz, enmType);
512	}
513	#endif /* unused */
514
515
516	/**
517	* Simplifies a string variable.
518	*
519	* @param pVar The variable.
520	*/
521	static void expr_var_make_simple_string(PEXPRVAR pVar)
522	{
523	switch (pVar->enmType)
524	{
525	case kExprVar_Num:
526	{
527	char psz = (char )xmalloc(EXPR_NUM_LEN);
528	expr_num_to_string(psz, pVar->uVal.i);
529	pVar->uVal.psz = psz;
530	pVar->enmType = kExprVar_SimpleString;
531	break;
532	}
533
534	case kExprVar_String:
535	case kExprVar_QuotedString:
536	{
537	char *psz;
538	assert(strchr(pVar->uVal.psz, '$'));
539
540	psz = allocated_variable_expand(pVar->uVal.psz);
541	free(pVar->uVal.psz);
542	pVar->uVal.psz = psz;
543
544	pVar->enmType = pVar->enmType == kExprVar_String
545	? kExprVar_SimpleString
546	: kExprVar_QuotedSimpleString;
547	break;
548	}
549
550	case kExprVar_SimpleString:
551	case kExprVar_QuotedSimpleString:
552	/* nothing to do. */
553	break;
554
555	default:
556	assert(0);
557	}
558	}
559
560
561	#if 0 /* unused */
562	/**
563	* Turns a variable into a string value.
564	*
565	* @param pVar The variable.
566	*/
567	static void expr_var_make_string(PEXPRVAR pVar)
568	{
569	switch (pVar->enmType)
570	{
571	case kExprVar_Num:
572	expr_var_make_simple_string(pVar);
573	break;
574
575	case kExprVar_String:
576	case kExprVar_SimpleString:
577	case kExprVar_QuotedString:
578	case kExprVar_QuotedSimpleString:
579	/* nothing to do. */
580	break;
581
582	default:
583	assert(0);
584	}
585	}
586	#endif /* unused */
587
588
589	/**
590	* Initializes a new variables with a integer value.
591	*
592	* @param pVar The new variable.
593	* @param i The integer value.
594	*/
595	static void expr_var_init_num(PEXPRVAR pVar, EXPRINT64 i)
596	{
597	pVar->enmType = kExprVar_Num;
598	pVar->uVal.i = i;
599	}
600
601
602	/**
603	* Assigns a integer value to a variable.
604	*
605	* @param pVar The variable.
606	* @param i The integer value.
607	*/
608	static void expr_var_assign_num(PEXPRVAR pVar, EXPRINT64 i)
609	{
610	expr_var_delete(pVar);
611	expr_var_init_num(pVar, i);
612	}
613
614
615	/**
616	* Turns the variable into a number.
617	*
618	* @returns status code.
619	* @param pThis The evaluator instance.
620	* @param pVar The variable.
621	*/
622	static EXPRRET expr_var_make_num(PEXPR pThis, PEXPRVAR pVar)
623	{
624	switch (pVar->enmType)
625	{
626	case kExprVar_Num:
627	/* nothing to do. */
628	break;
629
630	case kExprVar_String:
631	expr_var_make_simple_string(pVar);
632	/* fall thru */
633	case kExprVar_SimpleString:
634	{
635	EXPRINT64 i;
636	EXPRRET rc = expr_string_to_num(pThis, &i, pVar->uVal.psz, 0 /* fQuiet */);
637	if (rc < kExprRet_Ok)
638	return rc;
639	expr_var_assign_num(pVar, i);
640	break;
641	}
642
643	case kExprVar_QuotedString:
644	case kExprVar_QuotedSimpleString:
645	expr_error(pThis, "Cannot convert a quoted string to a number");
646	return kExprRet_Error;
647
648	default:
649	assert(0);
650	return kExprRet_Error;
651	}
652
653	return kExprRet_Ok;
654	}
655
656
657	/**
658	* Try to turn the variable into a number.
659	*
660	* @returns status code.
661	* @param pVar The variable.
662	*/
663	static EXPRRET expr_var_try_make_num(PEXPRVAR pVar)
664	{
665	switch (pVar->enmType)
666	{
667	case kExprVar_Num:
668	/* nothing to do. */
669	break;
670
671	case kExprVar_String:
672	expr_var_make_simple_string(pVar);
673	/* fall thru */
674	case kExprVar_SimpleString:
675	{
676	EXPRINT64 i;
677	EXPRRET rc = expr_string_to_num(NULL, &i, pVar->uVal.psz, 1 /* fQuiet */);
678	if (rc < kExprRet_Ok)
679	return rc;
680	expr_var_assign_num(pVar, i);
681	break;
682	}
683
684	default:
685	assert(0);
686	case kExprVar_QuotedString:
687	case kExprVar_QuotedSimpleString:
688	/* can't do this */
689	return kExprRet_Error;
690	}
691
692	return kExprRet_Ok;
693	}
694
695
696	/**
697	* Initializes a new variables with a boolean value.
698	*
699	* @param pVar The new variable.
700	* @param f The boolean value.
701	*/
702	static void expr_var_init_bool(PEXPRVAR pVar, int f)
703	{
704	pVar->enmType = kExprVar_Num;
705	pVar->uVal.i = !!f;
706	}
707
708
709	/**
710	* Assigns a boolean value to a variable.
711	*
712	* @param pVar The variable.
713	* @param f The boolean value.
714	*/
715	static void expr_var_assign_bool(PEXPRVAR pVar, int f)
716	{
717	expr_var_delete(pVar);
718	expr_var_init_bool(pVar, f);
719	}
720
721
722	/**
723	* Turns the variable into an boolean.
724	*
725	* @returns the boolean interpretation.
726	* @param pVar The variable.
727	*/
728	static int expr_var_make_bool(PEXPRVAR pVar)
729	{
730	switch (pVar->enmType)
731	{
732	case kExprVar_Num:
733	pVar->uVal.i = !!pVar->uVal.i;
734	break;
735
736	case kExprVar_String:
737	expr_var_make_simple_string(pVar);
738	/* fall thru */
739	case kExprVar_SimpleString:
740	{
741	/*
742	* Try convert it to a number. If that fails, use the
743	* GNU make boolean logic - not empty string means true.
744	*/
745	EXPRINT64 iVal;
746	char const *psz = pVar->uVal.psz;
747	while (isblank((unsigned char)*psz))
748	psz++;
749	if ( *psz
750	&& expr_string_to_num(NULL, &iVal, psz, 1 /* fQuiet */) >= kExprRet_Ok)
751	expr_var_assign_bool(pVar, iVal != 0);
752	else
753	expr_var_assign_bool(pVar, *psz != '\0');
754	break;
755	}
756
757	case kExprVar_QuotedString:
758	expr_var_make_simple_string(pVar);
759	/* fall thru */
760	case kExprVar_QuotedSimpleString:
761	/*
762	* Use GNU make boolean logic (not empty string means true).
763	* No stripping here, the string is quoted.
764	*/
765	expr_var_assign_bool(pVar, *pVar->uVal.psz != '\0');
766	break;
767
768	default:
769	assert(0);
770	break;
771	}
772
773	return pVar->uVal.i;
774	}
775
776
777	/**
778	* Pops a varable off the stack and deletes it.
779	* @param pThis The evaluator instance.
780	*/
781	static void expr_pop_and_delete_var(PEXPR pThis)
782	{
783	expr_var_delete(&pThis->aVars[pThis->iVar]);
784	pThis->iVar--;
785	}
786
787
788
789	/**
790	* Tries to make the variables the same type.
791	*
792	* This will not convert numbers to strings, unless one of them
793	* is a quoted string.
794	*
795	* this will try convert both to numbers if neither is quoted. Both
796	* conversions will have to suceed for this to be commited.
797	*
798	* All strings will be simplified.
799	*
800	* @returns status code. Done complaining on failure.
801	*
802	* @param pThis The evaluator instance.
803	* @param pVar1 The first variable.
804	* @param pVar2 The second variable.
805	*/
806	static EXPRRET expr_var_unify_types(PEXPR pThis, PEXPRVAR pVar1, PEXPRVAR pVar2, const char *pszOp)
807	{
808	/*
809	* Try make the variables the same type before comparing.
810	*/
811	if ( !expr_var_was_quoted(pVar1)
812	&& !expr_var_was_quoted(pVar2))
813	{
814	if ( expr_var_is_string(pVar1)
815	\|\| expr_var_is_string(pVar2))
816	{
817	if (!expr_var_is_string(pVar1))
818	expr_var_try_make_num(pVar2);
819	else if (!expr_var_is_string(pVar2))
820	expr_var_try_make_num(pVar1);
821	else
822	{
823	/*
824	* Both are strings, simplify them then see if both can be made into numbers.
825	*/
826	EXPRINT64 iVar1;
827	EXPRINT64 iVar2;
828
829	expr_var_make_simple_string(pVar1);
830	expr_var_make_simple_string(pVar2);
831
832	if ( expr_string_to_num(NULL, &iVar1, pVar1->uVal.psz, 1 /* fQuiet */) >= kExprRet_Ok
833	&& expr_string_to_num(NULL, &iVar2, pVar2->uVal.psz, 1 /* fQuiet */) >= kExprRet_Ok)
834	{
835	expr_var_assign_num(pVar1, iVar1);
836	expr_var_assign_num(pVar2, iVar2);
837	}
838	}
839	}
840	}
841	else
842	{
843	expr_var_make_simple_string(pVar1);
844	expr_var_make_simple_string(pVar2);
845	}
846
847	/*
848	* Complain if they aren't the same type now.
849	*/
850	if (expr_var_is_string(pVar1) != expr_var_is_string(pVar2))
851	{
852	expr_error(pThis, "Unable to unify types for \"%s\"", pszOp);
853	return kExprRet_Error;
854	}
855	return kExprRet_Ok;
856	}
857
858
859	/**
860	* Is variable defined, unary.
861	*
862	* @returns Status code.
863	* @param pThis The instance.
864	*/
865	static EXPRRET expr_op_defined(PEXPR pThis)
866	{
867	PEXPRVAR pVar = &pThis->aVars[pThis->iVar];
868	struct variable *pMakeVar;
869
870	expr_var_make_simple_string(pVar);
871	pMakeVar = lookup_variable(pVar->uVal.psz, strlen(pVar->uVal.psz));
872	expr_var_assign_bool(pVar, pMakeVar && *pMakeVar->value != '\0');
873
874	return kExprRet_Ok;
875	}
876
877
878	/**
879	* Is target defined, unary.
880	*
881	* @returns Status code.
882	* @param pThis The instance.
883	*/
884	static EXPRRET expr_op_target(PEXPR pThis)
885	{
886	PEXPRVAR pVar = &pThis->aVars[pThis->iVar];
887	struct file *pFile = NULL;
888
889	/*
890	* Because of secondary target expansion, lookup the unexpanded
891	* name first.
892	*/
893	#ifdef CONFIG_WITH_2ND_TARGET_EXPANSION
894	if ( pVar->enmType == kExprVar_String
895	\|\| pVar->enmType == kExprVar_QuotedString)
896	{
897	pFile = lookup_file(pVar->uVal.psz);
898	if ( pFile
899	&& !pFile->need_2nd_target_expansion)
900	pFile = NULL;
901	}
902	if (!pFile)
903	#endif
904	{
905	expr_var_make_simple_string(pVar);
906	pFile = lookup_file(pVar->uVal.psz);
907	}
908
909	/*
910	* Always inspect the head of a multiple target rule
911	* and look for a file with commands.
912	*/
913	#ifdef CONFIG_WITH_EXPLICIT_MULTITARGET
914	if (pFile && pFile->multi_head)
915	pFile = pFile->multi_head;
916	#endif
917
918	while (pFile && !pFile->cmds)
919	pFile = pFile->prev;
920
921	expr_var_assign_bool(pVar, pFile != NULL && pFile->is_target);
922
923	return kExprRet_Ok;
924	}
925
926
927	/**
928	* Convert to boolean.
929	*
930	* @returns Status code.
931	* @param pThis The instance.
932	*/
933	static EXPRRET expr_op_bool(PEXPR pThis)
934	{
935	expr_var_make_bool(&pThis->aVars[pThis->iVar]);
936	return kExprRet_Ok;
937	}
938
939
940	/**
941	* Convert to number, works on quoted strings too.
942	*
943	* @returns Status code.
944	* @param pThis The instance.
945	*/
946	static EXPRRET expr_op_num(PEXPR pThis)
947	{
948	PEXPRVAR pVar = &pThis->aVars[pThis->iVar];
949
950	/* unquote the string */
951	if (pVar->enmType == kExprVar_QuotedSimpleString)
952	pVar->enmType = kExprVar_SimpleString;
953	else if (pVar->enmType == kExprVar_QuotedString)
954	pVar->enmType = kExprVar_String;
955
956	return expr_var_make_num(pThis, pVar);
957	}
958
959
960	/**
961	* Convert to string (simplified and quoted)
962	*
963	* @returns Status code.
964	* @param pThis The instance.
965	*/
966	static EXPRRET expr_op_str(PEXPR pThis)
967	{
968	PEXPRVAR pVar = &pThis->aVars[pThis->iVar];
969
970	expr_var_make_simple_string(pVar);
971	pVar->enmType = kExprVar_QuotedSimpleString;
972
973	return kExprRet_Ok;
974	}
975
976
977	/**
978	* Pluss (dummy / make_integer)
979	*
980	* @returns Status code.
981	* @param pThis The instance.
982	*/
983	static EXPRRET expr_op_pluss(PEXPR pThis)
984	{
985	return expr_var_make_num(pThis, &pThis->aVars[pThis->iVar]);
986	}
987
988
989	/**
990	* Minus (negate)
991	*
992	* @returns Status code.
993	* @param pThis The instance.
994	*/
995	static EXPRRET expr_op_minus(PEXPR pThis)
996	{
997	EXPRRET rc;
998	PEXPRVAR pVar = &pThis->aVars[pThis->iVar];
999
1000	rc = expr_var_make_num(pThis, pVar);
1001	if (rc >= kExprRet_Ok)
1002	pVar->uVal.i = -pVar->uVal.i;
1003
1004	return rc;
1005	}
1006
1007
1008
1009	/**
1010	* Bitwise NOT.
1011	*
1012	* @returns Status code.
1013	* @param pThis The instance.
1014	*/
1015	static EXPRRET expr_op_bitwise_not(PEXPR pThis)
1016	{
1017	EXPRRET rc;
1018	PEXPRVAR pVar = &pThis->aVars[pThis->iVar];
1019
1020	rc = expr_var_make_num(pThis, pVar);
1021	if (rc >= kExprRet_Ok)
1022	pVar->uVal.i = ~pVar->uVal.i;
1023
1024	return rc;
1025	}
1026
1027
1028	/**
1029	* Logical NOT.
1030	*
1031	* @returns Status code.
1032	* @param pThis The instance.
1033	*/
1034	static EXPRRET expr_op_logical_not(PEXPR pThis)
1035	{
1036	PEXPRVAR pVar = &pThis->aVars[pThis->iVar];
1037
1038	expr_var_make_bool(pVar);
1039	pVar->uVal.i = !pVar->uVal.i;
1040
1041	return kExprRet_Ok;
1042	}
1043
1044
1045	/**
1046	* Multiplication.
1047	*
1048	* @returns Status code.
1049	* @param pThis The instance.
1050	*/
1051	static EXPRRET expr_op_multiply(PEXPR pThis)
1052	{
1053	EXPRRET rc = kExprRet_Ok;
1054	PEXPRVAR pVar1 = &pThis->aVars[pThis->iVar - 1];
1055	PEXPRVAR pVar2 = &pThis->aVars[pThis->iVar];
1056
1057	rc = expr_var_make_num(pThis, pVar1);
1058	if (rc >= kExprRet_Ok)
1059	{
1060	rc = expr_var_make_num(pThis, pVar2);
1061	if (rc >= kExprRet_Ok)
1062	pVar1->uVal.i *= pVar2->uVal.i;
1063	}
1064
1065	expr_pop_and_delete_var(pThis);
1066	return rc;
1067	}
1068
1069
1070
1071	/**
1072	* Division.
1073	*
1074	* @returns Status code.
1075	* @param pThis The instance.
1076	*/
1077	static EXPRRET expr_op_divide(PEXPR pThis)
1078	{
1079	EXPRRET rc = kExprRet_Ok;
1080	PEXPRVAR pVar1 = &pThis->aVars[pThis->iVar - 1];
1081	PEXPRVAR pVar2 = &pThis->aVars[pThis->iVar];
1082
1083	rc = expr_var_make_num(pThis, pVar1);
1084	if (rc >= kExprRet_Ok)
1085	{
1086	rc = expr_var_make_num(pThis, pVar2);
1087	if (rc >= kExprRet_Ok)
1088	pVar1->uVal.i /= pVar2->uVal.i;
1089	}
1090
1091	expr_pop_and_delete_var(pThis);
1092	return rc;
1093	}
1094
1095
1096
1097	/**
1098	* Modulus.
1099	*
1100	* @returns Status code.
1101	* @param pThis The instance.
1102	*/
1103	static EXPRRET expr_op_modulus(PEXPR pThis)
1104	{
1105	EXPRRET rc = kExprRet_Ok;
1106	PEXPRVAR pVar1 = &pThis->aVars[pThis->iVar - 1];
1107	PEXPRVAR pVar2 = &pThis->aVars[pThis->iVar];
1108
1109	rc = expr_var_make_num(pThis, pVar1);
1110	if (rc >= kExprRet_Ok)
1111	{
1112	rc = expr_var_make_num(pThis, pVar2);
1113	if (rc >= kExprRet_Ok)
1114	pVar1->uVal.i %= pVar2->uVal.i;
1115	}
1116
1117	expr_pop_and_delete_var(pThis);
1118	return rc;
1119	}
1120
1121
1122
1123	/**
1124	* Addition (numeric).
1125	*
1126	* @returns Status code.
1127	* @param pThis The instance.
1128	*/
1129	static EXPRRET expr_op_add(PEXPR pThis)
1130	{
1131	EXPRRET rc = kExprRet_Ok;
1132	PEXPRVAR pVar1 = &pThis->aVars[pThis->iVar - 1];
1133	PEXPRVAR pVar2 = &pThis->aVars[pThis->iVar];
1134
1135	rc = expr_var_make_num(pThis, pVar1);
1136	if (rc >= kExprRet_Ok)
1137	{
1138	rc = expr_var_make_num(pThis, pVar2);
1139	if (rc >= kExprRet_Ok)
1140	pVar1->uVal.i += pVar2->uVal.i;
1141	}
1142
1143	expr_pop_and_delete_var(pThis);
1144	return rc;
1145	}
1146
1147
1148	/**
1149	* Subtract (numeric).
1150	*
1151	* @returns Status code.
1152	* @param pThis The instance.
1153	*/
1154	static EXPRRET expr_op_sub(PEXPR pThis)
1155	{
1156	EXPRRET rc = kExprRet_Ok;
1157	PEXPRVAR pVar1 = &pThis->aVars[pThis->iVar - 1];
1158	PEXPRVAR pVar2 = &pThis->aVars[pThis->iVar];
1159
1160	rc = expr_var_make_num(pThis, pVar1);
1161	if (rc >= kExprRet_Ok)
1162	{
1163	rc = expr_var_make_num(pThis, pVar2);
1164	if (rc >= kExprRet_Ok)
1165	pVar1->uVal.i -= pVar2->uVal.i;
1166	}
1167
1168	expr_pop_and_delete_var(pThis);
1169	return rc;
1170	}
1171
1172	/**
1173	* Bitwise left shift.
1174	*
1175	* @returns Status code.
1176	* @param pThis The instance.
1177	*/
1178	static EXPRRET expr_op_shift_left(PEXPR pThis)
1179	{
1180	EXPRRET rc = kExprRet_Ok;
1181	PEXPRVAR pVar1 = &pThis->aVars[pThis->iVar - 1];
1182	PEXPRVAR pVar2 = &pThis->aVars[pThis->iVar];
1183
1184	rc = expr_var_make_num(pThis, pVar1);
1185	if (rc >= kExprRet_Ok)
1186	{
1187	rc = expr_var_make_num(pThis, pVar2);
1188	if (rc >= kExprRet_Ok)
1189	pVar1->uVal.i <<= pVar2->uVal.i;
1190	}
1191
1192	expr_pop_and_delete_var(pThis);
1193	return rc;
1194	}
1195
1196
1197	/**
1198	* Bitwise right shift.
1199	*
1200	* @returns Status code.
1201	* @param pThis The instance.
1202	*/
1203	static EXPRRET expr_op_shift_right(PEXPR pThis)
1204	{
1205	EXPRRET rc = kExprRet_Ok;
1206	PEXPRVAR pVar1 = &pThis->aVars[pThis->iVar - 1];
1207	PEXPRVAR pVar2 = &pThis->aVars[pThis->iVar];
1208
1209	rc = expr_var_make_num(pThis, pVar1);
1210	if (rc >= kExprRet_Ok)
1211	{
1212	rc = expr_var_make_num(pThis, pVar2);
1213	if (rc >= kExprRet_Ok)
1214	pVar1->uVal.i >>= pVar2->uVal.i;
1215	}
1216
1217	expr_pop_and_delete_var(pThis);
1218	return rc;
1219	}
1220
1221
1222	/**
1223	* Less than or equal
1224	*
1225	* @returns Status code.
1226	* @param pThis The instance.
1227	*/
1228	static EXPRRET expr_op_less_or_equal_than(PEXPR pThis)
1229	{
1230	EXPRRET rc = kExprRet_Ok;
1231	PEXPRVAR pVar1 = &pThis->aVars[pThis->iVar - 1];
1232	PEXPRVAR pVar2 = &pThis->aVars[pThis->iVar];
1233
1234	rc = expr_var_unify_types(pThis, pVar1, pVar2, "<=");
1235	if (rc >= kExprRet_Ok)
1236	{
1237	if (!expr_var_is_string(pVar1))
1238	expr_var_assign_bool(pVar1, pVar1->uVal.i <= pVar2->uVal.i);
1239	else
1240	expr_var_assign_bool(pVar1, strcmp(pVar1->uVal.psz, pVar2->uVal.psz) <= 0);
1241	}
1242
1243	expr_pop_and_delete_var(pThis);
1244	return rc;
1245	}
1246
1247
1248	/**
1249	* Less than.
1250	*
1251	* @returns Status code.
1252	* @param pThis The instance.
1253	*/
1254	static EXPRRET expr_op_less_than(PEXPR pThis)
1255	{
1256	EXPRRET rc = kExprRet_Ok;
1257	PEXPRVAR pVar1 = &pThis->aVars[pThis->iVar - 1];
1258	PEXPRVAR pVar2 = &pThis->aVars[pThis->iVar];
1259
1260	rc = expr_var_unify_types(pThis, pVar1, pVar2, "<");
1261	if (rc >= kExprRet_Ok)
1262	{
1263	if (!expr_var_is_string(pVar1))
1264	expr_var_assign_bool(pVar1, pVar1->uVal.i < pVar2->uVal.i);
1265	else
1266	expr_var_assign_bool(pVar1, strcmp(pVar1->uVal.psz, pVar2->uVal.psz) < 0);
1267	}
1268
1269	expr_pop_and_delete_var(pThis);
1270	return rc;
1271	}
1272
1273
1274	/**
1275	* Greater or equal than
1276	*
1277	* @returns Status code.
1278	* @param pThis The instance.
1279	*/
1280	static EXPRRET expr_op_greater_or_equal_than(PEXPR pThis)
1281	{
1282	EXPRRET rc = kExprRet_Ok;
1283	PEXPRVAR pVar1 = &pThis->aVars[pThis->iVar - 1];
1284	PEXPRVAR pVar2 = &pThis->aVars[pThis->iVar];
1285
1286	rc = expr_var_unify_types(pThis, pVar1, pVar2, ">=");
1287	if (rc >= kExprRet_Ok)
1288	{
1289	if (!expr_var_is_string(pVar1))
1290	expr_var_assign_bool(pVar1, pVar1->uVal.i >= pVar2->uVal.i);
1291	else
1292	expr_var_assign_bool(pVar1, strcmp(pVar1->uVal.psz, pVar2->uVal.psz) >= 0);
1293	}
1294
1295	expr_pop_and_delete_var(pThis);
1296	return rc;
1297	}
1298
1299
1300	/**
1301	* Greater than.
1302	*
1303	* @returns Status code.
1304	* @param pThis The instance.
1305	*/
1306	static EXPRRET expr_op_greater_than(PEXPR pThis)
1307	{
1308	EXPRRET rc = kExprRet_Ok;
1309	PEXPRVAR pVar1 = &pThis->aVars[pThis->iVar - 1];
1310	PEXPRVAR pVar2 = &pThis->aVars[pThis->iVar];
1311
1312	rc = expr_var_unify_types(pThis, pVar1, pVar2, ">");
1313	if (rc >= kExprRet_Ok)
1314	{
1315	if (!expr_var_is_string(pVar1))
1316	expr_var_assign_bool(pVar1, pVar1->uVal.i > pVar2->uVal.i);
1317	else
1318	expr_var_assign_bool(pVar1, strcmp(pVar1->uVal.psz, pVar2->uVal.psz) > 0);
1319	}
1320
1321	expr_pop_and_delete_var(pThis);
1322	return rc;
1323	}
1324
1325
1326	/**
1327	* Equal.
1328	*
1329	* @returns Status code.
1330	* @param pThis The instance.
1331	*/
1332	static EXPRRET expr_op_equal(PEXPR pThis)
1333	{
1334	EXPRRET rc = kExprRet_Ok;
1335	PEXPRVAR pVar1 = &pThis->aVars[pThis->iVar - 1];
1336	PEXPRVAR pVar2 = &pThis->aVars[pThis->iVar];
1337
1338	/*
1339	* The same type?
1340	*/
1341	if (expr_var_is_string(pVar1) == expr_var_is_string(pVar2))
1342	{
1343	if (!expr_var_is_string(pVar1))
1344	/* numbers are simple */
1345	expr_var_assign_bool(pVar1, pVar1->uVal.i == pVar2->uVal.i);
1346	else
1347	{
1348	/* try a normal string compare. */
1349	expr_var_make_simple_string(pVar1);
1350	expr_var_make_simple_string(pVar2);
1351	if (!strcmp(pVar1->uVal.psz, pVar2->uVal.psz))
1352	expr_var_assign_bool(pVar1, 1);
1353	/* try convert and compare as number instead. */
1354	else if ( expr_var_try_make_num(pVar1) >= kExprRet_Ok
1355	&& expr_var_try_make_num(pVar2) >= kExprRet_Ok)
1356	expr_var_assign_bool(pVar1, pVar1->uVal.i == pVar2->uVal.i);
1357	/* ok, they really aren't equal. */
1358	else
1359	expr_var_assign_bool(pVar1, 0);
1360	}
1361	}
1362	else
1363	{
1364	/*
1365	* If the type differs, there are now two options:
1366	* 1. Convert the string to a valid number and compare the numbers.
1367	* 2. Convert an empty string to a 'false' boolean value and compare
1368	* numerically. This one is a bit questionable, so we don't try this.
1369	*/
1370	if ( expr_var_try_make_num(pVar1) >= kExprRet_Ok
1371	&& expr_var_try_make_num(pVar2) >= kExprRet_Ok)
1372	expr_var_assign_bool(pVar1, pVar1->uVal.i == pVar2->uVal.i);
1373	else
1374	{
1375	expr_error(pThis, "Cannot compare strings and numbers");
1376	rc = kExprRet_Error;
1377	}
1378	}
1379
1380	expr_pop_and_delete_var(pThis);
1381	return kExprRet_Ok;
1382	}
1383
1384
1385	/**
1386	* Not equal.
1387	*
1388	* @returns Status code.
1389	* @param pThis The instance.
1390	*/
1391	static EXPRRET expr_op_not_equal(PEXPR pThis)
1392	{
1393	EXPRRET rc = expr_op_equal(pThis);
1394	if (rc >= kExprRet_Ok)
1395	rc = expr_op_logical_not(pThis);
1396	return rc;
1397	}
1398
1399
1400	/**
1401	* Bitwise AND.
1402	*
1403	* @returns Status code.
1404	* @param pThis The instance.
1405	*/
1406	static EXPRRET expr_op_bitwise_and(PEXPR pThis)
1407	{
1408	PEXPRVAR pVar1 = &pThis->aVars[pThis->iVar - 1];
1409	PEXPRVAR pVar2 = &pThis->aVars[pThis->iVar];
1410	EXPRRET rc;
1411
1412	rc = expr_var_make_num(pThis, pVar1);
1413	if (rc >= kExprRet_Ok)
1414	{
1415	rc = expr_var_make_num(pThis, pVar2);
1416	if (rc >= kExprRet_Ok)
1417	pVar1->uVal.i &= pVar2->uVal.i;
1418	}
1419
1420	expr_pop_and_delete_var(pThis);
1421	return kExprRet_Ok;
1422	}
1423
1424
1425	/**
1426	* Bitwise XOR.
1427	*
1428	* @returns Status code.
1429	* @param pThis The instance.
1430	*/
1431	static EXPRRET expr_op_bitwise_xor(PEXPR pThis)
1432	{
1433	PEXPRVAR pVar1 = &pThis->aVars[pThis->iVar - 1];
1434	PEXPRVAR pVar2 = &pThis->aVars[pThis->iVar];
1435	EXPRRET rc;
1436
1437	rc = expr_var_make_num(pThis, pVar1);
1438	if (rc >= kExprRet_Ok)
1439	{
1440	rc = expr_var_make_num(pThis, pVar2);
1441	if (rc >= kExprRet_Ok)
1442	pVar1->uVal.i ^= pVar2->uVal.i;
1443	}
1444
1445	expr_pop_and_delete_var(pThis);
1446	return kExprRet_Ok;
1447	}
1448
1449
1450	/**
1451	* Bitwise OR.
1452	*
1453	* @returns Status code.
1454	* @param pThis The instance.
1455	*/
1456	static EXPRRET expr_op_bitwise_or(PEXPR pThis)
1457	{
1458	PEXPRVAR pVar1 = &pThis->aVars[pThis->iVar - 1];
1459	PEXPRVAR pVar2 = &pThis->aVars[pThis->iVar];
1460	EXPRRET rc;
1461
1462	rc = expr_var_make_num(pThis, pVar1);
1463	if (rc >= kExprRet_Ok)
1464	{
1465	rc = expr_var_make_num(pThis, pVar2);
1466	if (rc >= kExprRet_Ok)
1467	pVar1->uVal.i \|= pVar2->uVal.i;
1468	}
1469
1470	expr_pop_and_delete_var(pThis);
1471	return kExprRet_Ok;
1472	}
1473
1474
1475	/**
1476	* Logical AND.
1477	*
1478	* @returns Status code.
1479	* @param pThis The instance.
1480	*/
1481	static EXPRRET expr_op_logical_and(PEXPR pThis)
1482	{
1483	PEXPRVAR pVar1 = &pThis->aVars[pThis->iVar - 1];
1484	PEXPRVAR pVar2 = &pThis->aVars[pThis->iVar];
1485
1486	if ( expr_var_make_bool(pVar1)
1487	&& expr_var_make_bool(pVar2))
1488	expr_var_assign_bool(pVar1, 1);
1489	else
1490	expr_var_assign_bool(pVar1, 0);
1491
1492	expr_pop_and_delete_var(pThis);
1493	return kExprRet_Ok;
1494	}
1495
1496
1497	/**
1498	* Logical OR.
1499	*
1500	* @returns Status code.
1501	* @param pThis The instance.
1502	*/
1503	static EXPRRET expr_op_logical_or(PEXPR pThis)
1504	{
1505	PEXPRVAR pVar1 = &pThis->aVars[pThis->iVar - 1];
1506	PEXPRVAR pVar2 = &pThis->aVars[pThis->iVar];
1507
1508	if ( expr_var_make_bool(pVar1)
1509	\|\| expr_var_make_bool(pVar2))
1510	expr_var_assign_bool(pVar1, 1);
1511	else
1512	expr_var_assign_bool(pVar1, 0);
1513
1514	expr_pop_and_delete_var(pThis);
1515	return kExprRet_Ok;
1516	}
1517
1518
1519	/**
1520	* Left parenthesis.
1521	*
1522	* @returns Status code.
1523	* @param pThis The instance.
1524	*/
1525	static EXPRRET expr_op_left_parenthesis(PEXPR pThis)
1526	{
1527	/*
1528	* There should be a right parenthesis operator lined up for us now,
1529	* eat it. If not found there is an inbalance.
1530	*/
1531	EXPRRET rc = expr_get_binary_or_eoe_or_rparen(pThis);
1532	if ( rc == kExprRet_Operator
1533	&& pThis->apOps[pThis->iOp]->szOp[0] == ')')
1534	{
1535	/* pop it and get another one which we can leave pending. */
1536	pThis->iOp--;
1537	rc = expr_get_binary_or_eoe_or_rparen(pThis);
1538	if (rc >= kExprRet_Ok)
1539	expr_unget_op(pThis);
1540	}
1541	else
1542	{
1543	expr_error(pThis, "Missing ')'");
1544	rc = kExprRet_Error;
1545	}
1546
1547	return rc;
1548	}
1549
1550
1551	/**
1552	* Right parenthesis, dummy that's never actually called.
1553	*
1554	* @returns Status code.
1555	* @param pThis The instance.
1556	*/
1557	static EXPRRET expr_op_right_parenthesis(PEXPR pThis)
1558	{
1559	assert(0);
1560	(void)pThis;
1561	return kExprRet_Ok;
1562	}
1563
1564
1565
1566
1567
1568	/**
1569	* The operator table.
1570	*
1571	* This table is NOT ordered by precedence, but for linear search
1572	* allowing for first match to return the correct operator. This
1573	* means that \|\| must come before \|, or else \| will match all.
1574	*/
1575	static const EXPROP g_aExprOps[] =
1576	{
1577	#define EXPR_OP(szOp, iPrecedence, cArgs, pfn) { szOp, sizeof(szOp) - 1, '\0', iPrecedence, cArgs, pfn }
1578	/* Name, iPrecedence, cArgs, pfn */
1579	EXPR_OP("defined", 90, 1, expr_op_defined),
1580	EXPR_OP("target", 90, 1, expr_op_target),
1581	EXPR_OP("bool", 90, 1, expr_op_bool),
1582	EXPR_OP("num", 90, 1, expr_op_num),
1583	EXPR_OP("str", 90, 1, expr_op_str),
1584	EXPR_OP("+", 80, 1, expr_op_pluss),
1585	EXPR_OP("-", 80, 1, expr_op_minus),
1586	EXPR_OP("~", 80, 1, expr_op_bitwise_not),
1587	EXPR_OP("*", 75, 2, expr_op_multiply),
1588	EXPR_OP("/", 75, 2, expr_op_divide),
1589	EXPR_OP("%", 75, 2, expr_op_modulus),
1590	EXPR_OP("+", 70, 2, expr_op_add),
1591	EXPR_OP("-", 70, 2, expr_op_sub),
1592	EXPR_OP("<<", 65, 2, expr_op_shift_left),
1593	EXPR_OP(">>", 65, 2, expr_op_shift_right),
1594	EXPR_OP("<=", 60, 2, expr_op_less_or_equal_than),
1595	EXPR_OP("<", 60, 2, expr_op_less_than),
1596	EXPR_OP(">=", 60, 2, expr_op_greater_or_equal_than),
1597	EXPR_OP(">", 60, 2, expr_op_greater_than),
1598	EXPR_OP("==", 55, 2, expr_op_equal),
1599	EXPR_OP("!=", 55, 2, expr_op_not_equal),
1600	EXPR_OP("!", 80, 1, expr_op_logical_not),
1601	EXPR_OP("^", 45, 2, expr_op_bitwise_xor),
1602	EXPR_OP("&&", 35, 2, expr_op_logical_and),
1603	EXPR_OP("&", 50, 2, expr_op_bitwise_and),
1604	EXPR_OP("\|\|", 30, 2, expr_op_logical_or),
1605	EXPR_OP("\|", 40, 2, expr_op_bitwise_or),
1606	{ "(", 1, ')', 10, 1, expr_op_left_parenthesis },
1607	{ ")", 1, '(', 10, 0, expr_op_right_parenthesis },
1608	/* { "?", 1, ':', 5, 2, expr_op_question },
1609	{ ":", 1, '?', 5, 2, expr_op_colon }, -- too weird for now. */
1610	#undef EXPR_OP
1611	};
1612
1613	/** Dummy end of expression fake. */
1614	static const EXPROP g_ExprEndOfExpOp =
1615	{
1616	"", 0, '\0', 0, 0, NULL
1617	};
1618
1619
1620	/**
1621	* Initializes the opcode character map if necessary.
1622	*/
1623	static void expr_map_init(void)
1624	{
1625	unsigned i;
1626	if (g_fExprInitializedMap)
1627	return;
1628
1629	/*
1630	* Initialize it.
1631	*/
1632	memset(&g_auchOpStartCharMap, 0, sizeof(g_auchOpStartCharMap));
1633	for (i = 0; i < sizeof(g_aExprOps) / sizeof(g_aExprOps[0]); i++)
1634	{
1635	unsigned int ch = (unsigned int)g_aExprOps[i].szOp[0];
1636	if (!g_auchOpStartCharMap[ch])
1637	g_auchOpStartCharMap[ch] = (i << 1) \| 1;
1638	}
1639
1640	g_fExprInitializedMap = 1;
1641	}
1642
1643
1644	/**
1645	* Looks up a character in the map.
1646	*
1647	* @returns the value for that char.
1648	* @retval 0 if not a potential opcode start char.
1649	* @retval non-zero if it's a potential operator. The low bit is always set
1650	* while the remaining 7 bits is the index into the operator table
1651	* of the first match.
1652	*
1653	* @param ch The character.
1654	*/
1655	static unsigned char expr_map_get(char ch)
1656	{
1657	return g_auchOpStartCharMap[(unsigned int)ch];
1658	}
1659
1660
1661	/**
1662	* Searches the operator table given a potential operator start char.
1663	*
1664	* @returns Pointer to the matching operator. NULL if not found.
1665	* @param psz Pointer to what can be an operator.
1666	* @param uchVal The expr_map_get value.
1667	* @param fUnary Whether it must be an unary operator or not.
1668	*/
1669	static PCEXPROP expr_lookup_op(char const *psz, unsigned char uchVal, int fUnary)
1670	{
1671	char ch = *psz;
1672	unsigned i;
1673
1674	for (i = uchVal >> 1; i < sizeof(g_aExprOps) / sizeof(g_aExprOps[0]); i++)
1675	{
1676	/* compare the string... */
1677	switch (g_aExprOps[i].cchOp)
1678	{
1679	case 1:
1680	if (g_aExprOps[i].szOp[0] != ch)
1681	continue;
1682	break;
1683	case 2:
1684	if ( g_aExprOps[i].szOp[0] != ch
1685	\|\| g_aExprOps[i].szOp[1] != psz[1])
1686	continue;
1687	break;
1688	default:
1689	if ( g_aExprOps[i].szOp[0] != ch
1690	\|\| strncmp(&g_aExprOps[i].szOp[1], psz + 1, g_aExprOps[i].cchOp - 1))
1691	continue;
1692	break;
1693	}
1694
1695	/* ... and the operator type. */
1696	if (fUnary == (g_aExprOps[i].cArgs == 1))
1697	{
1698	/* got a match! */
1699	return &g_aExprOps[i];
1700	}
1701	}
1702
1703	return NULL;
1704	}
1705
1706
1707	/**
1708	* Ungets a binary operator.
1709	*
1710	* The operator is poped from the stack and put in the pending position.
1711	*
1712	* @param pThis The evaluator instance.
1713	*/
1714	static void expr_unget_op(PEXPR pThis)
1715	{
1716	assert(pThis->pPending == NULL);
1717	assert(pThis->iOp >= 0);
1718
1719	pThis->pPending = pThis->apOps[pThis->iOp];
1720	pThis->apOps[pThis->iOp] = NULL;
1721	pThis->iOp--;
1722	}
1723
1724
1725
1726	/**
1727	* Get the next token, it should be a binary operator, or the end of
1728	* the expression, or a right parenthesis.
1729	*
1730	* The operator is pushed onto the stack and the status code indicates
1731	* which of the two we found.
1732	*
1733	* @returns status code. Will grumble on failure.
1734	* @retval kExprRet_EndOfExpr if we encountered the end of the expression.
1735	* @retval kExprRet_Operator if we encountered a binary operator or right
1736	* parenthesis. It's on the operator stack.
1737	*
1738	* @param pThis The evaluator instance.
1739	*/
1740	static EXPRRET expr_get_binary_or_eoe_or_rparen(PEXPR pThis)
1741	{
1742	/*
1743	* See if there is anything pending first.
1744	*/
1745	PCEXPROP pOp = pThis->pPending;
1746	if (pOp)
1747	pThis->pPending = NULL;
1748	else
1749	{
1750	/*
1751	* Eat more of the expression.
1752	*/
1753	char const *psz = pThis->psz;
1754
1755	/* spaces */
1756	while (isspace((unsigned int)*psz))
1757	psz++;
1758	/* see what we've got. */
1759	if (*psz)
1760	{
1761	unsigned char uchVal = expr_map_get(*psz);
1762	if (uchVal)
1763	pOp = expr_lookup_op(psz, uchVal, 0 /* fUnary */);
1764	if (!pOp)
1765	{
1766	expr_error(pThis, "Expected binary operator, found \"%.42s\"...", psz);
1767	return kExprRet_Error;
1768	}
1769	psz += pOp->cchOp;
1770	}
1771	else
1772	pOp = &g_ExprEndOfExpOp;
1773	pThis->psz = psz;
1774	}
1775
1776	/*
1777	* Push it.
1778	*/
1779	if (pThis->iOp >= EXPR_MAX_OPERATORS - 1)
1780	{
1781	expr_error(pThis, "Operator stack overflow");
1782	return kExprRet_Error;
1783	}
1784	pThis->apOps[++pThis->iOp] = pOp;
1785
1786	return pOp->iPrecedence
1787	? kExprRet_Operator
1788	: kExprRet_EndOfExpr;
1789	}
1790
1791
1792
1793	/**
1794	* Get the next token, it should be an unary operator or an operand.
1795	*
1796	* This will fail if encountering the end of the expression since
1797	* it is implied that there should be something more.
1798	*
1799	* The token is pushed onto the respective stack and the status code
1800	* indicates which it is.
1801	*
1802	* @returns status code. On failure we'll be done bitching already.
1803	* @retval kExprRet_Operator if we encountered an unary operator.
1804	* It's on the operator stack.
1805	* @retval kExprRet_Operand if we encountered an operand operator.
1806	* It's on the operand stack.
1807	*
1808	* @param This The evaluator instance.
1809	*/
1810	static EXPRRET expr_get_unary_or_operand(PEXPR pThis)
1811	{
1812	EXPRRET rc;
1813	unsigned char uchVal;
1814	PCEXPROP pOp;
1815	char const *psz = pThis->psz;
1816
1817	/*
1818	* Eat white space and make sure there is something after it.
1819	*/
1820	while (isspace((unsigned int)*psz))
1821	psz++;
1822	if (!*psz)
1823	{
1824	expr_error(pThis, "Unexpected end of expression");
1825	return kExprRet_Error;
1826	}
1827
1828	/*
1829	* Is it an operator?
1830	*/
1831	pOp = NULL;
1832	uchVal = expr_map_get(*psz);
1833	if (uchVal)
1834	pOp = expr_lookup_op(psz, uchVal, 1 /* fUnary */);
1835	if (pOp)
1836	{
1837	/*
1838	* Push the operator onto the stack.
1839	*/
1840	if (pThis->iVar < EXPR_MAX_OPERANDS - 1)
1841	{
1842	pThis->apOps[++pThis->iOp] = pOp;
1843	rc = kExprRet_Operator;
1844	}
1845	else
1846	{
1847	expr_error(pThis, "Operator stack overflow");
1848	rc = kExprRet_Error;
1849	}
1850	psz += pOp->cchOp;
1851	}
1852	else if (pThis->iVar < EXPR_MAX_OPERANDS - 1)
1853	{
1854	/*
1855	* It's an operand. Figure out where it ends and
1856	* push it onto the stack.
1857	*/
1858	const char *pszStart;
1859
1860	rc = kExprRet_Ok;
1861	if (*psz == '"')
1862	{
1863	pszStart = ++psz;
1864	while (psz && psz != '"')
1865	psz++;
1866	expr_var_init_substring(&pThis->aVars[++pThis->iVar], pszStart, psz - pszStart, kExprVar_QuotedString);
1867	if (*psz)
1868	psz++;
1869	}
1870	else if (*psz == '\'')
1871	{
1872	pszStart = ++psz;
1873	while (psz && psz != '\'')
1874	psz++;
1875	expr_var_init_substring(&pThis->aVars[++pThis->iVar], pszStart, psz - pszStart, kExprVar_QuotedSimpleString);
1876	if (*psz)
1877	psz++;
1878	}
1879	else
1880	{
1881	char achPars[20];
1882	int iPar = -1;
1883	char chEndPar = '\0';
1884	char ch, ch2;
1885
1886	pszStart = psz;
1887	while ((ch = *psz) != '\0')
1888	{
1889	/* $(adsf) or ${asdf} needs special handling. */
1890	if ( ch == '$'
1891	&& ( (ch2 = psz[1]) == '('
1892	\|\| ch2 == '{'))
1893	{
1894	psz++;
1895	if (iPar > (int)(sizeof(achPars) / sizeof(achPars[0])))
1896	{
1897	expr_error(pThis, "Too deep nesting of variable expansions");
1898	rc = kExprRet_Error;
1899	break;
1900	}
1901	achPars[++iPar] = chEndPar = ch2 == '(' ? ')' : '}';
1902	}
1903	else if (ch == chEndPar)
1904	{
1905	iPar--;
1906	chEndPar = iPar >= 0 ? achPars[iPar] : '\0';
1907	}
1908	else if (!chEndPar)
1909	{
1910	/** @todo combine isspace and expr_map_get! */
1911	unsigned chVal = expr_map_get(ch);
1912	if (chVal)
1913	{
1914	PCEXPROP pOp = expr_lookup_op(psz, uchVal, 0 /* fUnary */);
1915	if (pOp)
1916	break;
1917	}
1918	if (isspace((unsigned char)ch))
1919	break;
1920	}
1921
1922	/* next */
1923	psz++;
1924	}
1925
1926	if (rc == kExprRet_Ok)
1927	expr_var_init_substring(&pThis->aVars[++pThis->iVar], pszStart, psz - pszStart, kExprVar_String);
1928	}
1929	}
1930	else
1931	{
1932	expr_error(pThis, "Operand stack overflow");
1933	rc = kExprRet_Error;
1934	}
1935	pThis->psz = psz;
1936
1937	return rc;
1938	}
1939
1940
1941	/**
1942	* Evaluates the current expression.
1943	*
1944	* @returns status code.
1945	*
1946	* @param pThis The instance.
1947	*/
1948	static EXPRRET expr_eval(PEXPR pThis)
1949	{
1950	EXPRRET rc;
1951	PCEXPROP pOp;
1952
1953	/*
1954	* The main loop.
1955	*/
1956	for (;;)
1957	{
1958	/*
1959	* Eat unary operators until we hit an operand.
1960	*/
1961	do rc = expr_get_unary_or_operand(pThis);
1962	while (rc == kExprRet_Operator);
1963	if (rc < kExprRet_Error)
1964	break;
1965
1966	/*
1967	* Look for a binary operator, right parenthesis or end of expression.
1968	*/
1969	rc = expr_get_binary_or_eoe_or_rparen(pThis);
1970	if (rc < kExprRet_Error)
1971	break;
1972	expr_unget_op(pThis);
1973
1974	/*
1975	* Pop operators and apply them.
1976	*
1977	* Parenthesis will be handed via precedence, where the left parenthesis
1978	* will go pop the right one and make another operator pending.
1979	*/
1980	while ( pThis->iOp >= 0
1981	&& pThis->apOps[pThis->iOp]->iPrecedence >= pThis->pPending->iPrecedence)
1982	{
1983	pOp = pThis->apOps[pThis->iOp--];
1984	assert(pThis->iVar + 1 >= pOp->cArgs);
1985	rc = pOp->pfn(pThis);
1986	if (rc < kExprRet_Error)
1987	break;
1988	}
1989	if (rc < kExprRet_Error)
1990	break;
1991
1992	/*
1993	* Get the next binary operator or end of expression.
1994	* There should be no right parenthesis here.
1995	*/
1996	rc = expr_get_binary_or_eoe_or_rparen(pThis);
1997	if (rc < kExprRet_Error)
1998	break;
1999	pOp = pThis->apOps[pThis->iOp];
2000	if (!pOp->iPrecedence)
2001	break; /* end of expression */
2002	if (!pOp->cArgs)
2003	{
2004	expr_error(pThis, "Unexpected \"%s\"", pOp->szOp);
2005	rc = kExprRet_Error;
2006	break;
2007	}
2008	}
2009
2010	return rc;
2011	}
2012
2013
2014	/**
2015	* Destroys the given instance.
2016	*
2017	* @param pThis The instance to destroy.
2018	*/
2019	static void expr_destroy(PEXPR pThis)
2020	{
2021	while (pThis->iVar >= 0)
2022	{
2023	expr_var_delete(pThis->aVars);
2024	pThis->iVar--;
2025	}
2026	free(pThis);
2027	}
2028
2029
2030	/**
2031	* Instantiates an expression evaluator.
2032	*
2033	* @returns The instance.
2034	*
2035	* @param pszExpr What to parse.
2036	* This must stick around until expr_destroy.
2037	*/
2038	static PEXPR expr_create(char const *pszExpr)
2039	{
2040	PEXPR pThis = (PEXPR)xmalloc(sizeof(*pThis));
2041	pThis->pszExpr = pszExpr;
2042	pThis->psz = pszExpr;
2043	pThis->pFileLoc = NULL;
2044	pThis->pPending = NULL;
2045	pThis->iVar = -1;
2046	pThis->iOp = -1;
2047
2048	expr_map_init();
2049	return pThis;
2050	}
2051
2052
2053	/**
2054	* Evaluates the given if expression.
2055	*
2056	* @returns -1, 0 or 1.
2057	* @retval -1 if the expression is invalid.
2058	* @retval 0 if the expression is true
2059	* @retval 1 if the expression is false.
2060	*
2061	* @param line The expression. Can modify this as we like.
2062	* @param flocp The file location, used for errors.
2063	*/
2064	int expr_eval_if_conditionals(char line, const struct floc flocp)
2065	{
2066	/*
2067	* Instantiate the expression evaluator and let
2068	* it have a go at it.
2069	*/
2070	int rc = -1;
2071	PEXPR pExpr = expr_create(line);
2072	pExpr->pFileLoc = flocp;
2073	if (expr_eval(pExpr) >= kExprRet_Ok)
2074	{
2075	/*
2076	* Convert the result (on top of the stack) to boolean and
2077	* set our return value accordingly.
2078	*/
2079	if (expr_var_make_bool(&pExpr->aVars[0]))
2080	rc = 0;
2081	else
2082	rc = 1;
2083	}
2084	expr_destroy(pExpr);
2085
2086	return rc;
2087	}
2088
2089
2090	/**
2091	* Evaluates the given expression and returns the result as a string.
2092	*
2093	* @returns variable buffer position.
2094	*
2095	* @param o The current variable buffer position.
2096	* @param expr The expression.
2097	*/
2098	char expr_eval_to_string(char o, char *expr)
2099	{
2100	/*
2101	* Instantiate the expression evaluator and let
2102	* it have a go at it.
2103	*/
2104	PEXPR pExpr = expr_create(expr);
2105	if (expr_eval(pExpr) >= kExprRet_Ok)
2106	{
2107	/*
2108	* Convert the result (on top of the stack) to a string
2109	* and copy it out the variable buffer.
2110	*/
2111	PEXPRVAR pVar = &pExpr->aVars[0];
2112	expr_var_make_simple_string(pVar);
2113	o = variable_buffer_output(o, pVar->uVal.psz, strlen(pVar->uVal.psz));
2114	}
2115	else
2116	o = variable_buffer_output(o, "<expression evaluation failed>", sizeof("<expression evaluation failed>") - 1);
2117	expr_destroy(pExpr);
2118
2119	return o;
2120	}
2121
2122
2123	#endif /* CONFIG_WITH_IF_CONDITIONALS */
2124

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source: kBuild/trunk/src/kmk/expreval.c@ 2074

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