2 * Copyright (c) 1988, 1989, 1990, 1993
3 * The Regents of the University of California. All rights reserved.
4 * Copyright (c) 1988, 1989 by Adam de Boor
5 * Copyright (c) 1989 by Berkeley Softworks
8 * This code is derived from software contributed to Berkeley by
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12 * modification, are permitted provided that the following conditions
14 * 1. Redistributions of source code must retain the above copyright
15 * notice, this list of conditions and the following disclaimer.
16 * 2. Redistributions in binary form must reproduce the above copyright
17 * notice, this list of conditions and the following disclaimer in the
18 * documentation and/or other materials provided with the distribution.
19 * 3. All advertising materials mentioning features or use of this software
20 * must display the following acknowledgement:
21 * This product includes software developed by the University of
22 * California, Berkeley and its contributors.
23 * 4. Neither the name of the University nor the names of its contributors
24 * may be used to endorse or promote products derived from this software
25 * without specific prior written permission.
27 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
28 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
29 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
30 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
31 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
32 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
33 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
34 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
35 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
36 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
39 * @(#)cond.c 8.2 (Berkeley) 1/2/94
40 * $FreeBSD: src/usr.bin/make/cond.c,v 1.12.2.1 2003/07/22 08:03:13 ru Exp $
41 * $DragonFly: src/usr.bin/make/cond.c,v 1.8 2004/11/12 22:42:36 dillon Exp $
46 * Functions to handle conditionals in a makefile.
49 * Cond_Eval Evaluate the conditional in the passed line.
61 * The parsing of conditional expressions is based on this grammar:
66 * T -> defined(variable)
72 * T -> $(varspec) op value
73 * T -> $(varspec) == "string"
74 * T -> $(varspec) != "string"
77 * op -> == | != | > | < | >= | <=
79 * 'symbol' is some other symbol to which the default function (condDefProc)
82 * Tokens are scanned from the 'condExpr' string. The scanner (CondToken)
83 * will return And for '&' and '&&', Or for '|' and '||', Not for '!',
84 * LParen for '(', RParen for ')' and will evaluate the other terminal
85 * symbols, using either the default function or the function given in the
86 * terminal, and return the result as either True or False.
88 * All Non-Terminal functions (CondE, CondF and CondT) return Err on error.
91 And, Or, Not, True, False, LParen, RParen, EndOfFile, None, Err
95 * Structures to handle elegantly the different forms of #if's. The
96 * last two fields are stored in condInvert and condDefProc, respectively.
98 static void CondPushBack(Token);
99 static int CondGetArg(char **, char **, char *, Boolean);
100 static Boolean CondDoDefined(int, char *);
101 static int CondStrMatch(void *, void *);
102 static Boolean CondDoMake(int, char *);
103 static Boolean CondDoExists(int, char *);
104 static Boolean CondDoTarget(int, char *);
105 static char * CondCvtArg(char *, double *);
106 static Token CondToken(Boolean);
107 static Token CondT(Boolean);
108 static Token CondF(Boolean);
109 static Token CondE(Boolean);
112 char *form; /* Form of if */
113 int formlen; /* Length of form */
114 Boolean doNot; /* TRUE if default function should be negated */
115 Boolean (*defProc)(int, char *); /* Default function to apply */
117 { "ifdef", 5, FALSE, CondDoDefined },
118 { "ifndef", 6, TRUE, CondDoDefined },
119 { "ifmake", 6, FALSE, CondDoMake },
120 { "ifnmake", 7, TRUE, CondDoMake },
121 { "if", 2, FALSE, CondDoDefined },
122 { NULL, 0, FALSE, NULL }
125 static Boolean condInvert; /* Invert the default function */
126 static Boolean (*condDefProc) /* Default function to apply */
128 static char *condExpr; /* The expression to parse */
129 static Token condPushBack=None; /* Single push-back token used in
132 #define MAXIF 30 /* greatest depth of #if'ing */
134 static Boolean condStack[MAXIF]; /* Stack of conditionals's values */
135 static int condTop = MAXIF; /* Top-most conditional */
136 static int skipIfLevel=0; /* Depth of skipped conditionals */
137 static Boolean skipLine = FALSE; /* Whether the parse module is skipping
141 *-----------------------------------------------------------------------
143 * Push back the most recent token read. We only need one level of
144 * this, so the thing is just stored in 'condPushback'.
150 * condPushback is overwritten.
152 *-----------------------------------------------------------------------
156 Token t; /* Token to push back into the "stream" */
162 *-----------------------------------------------------------------------
164 * Find the argument of a built-in function.
167 * The length of the argument and the address of the argument.
170 * The pointer is set to point to the closing parenthesis of the
173 *-----------------------------------------------------------------------
176 CondGetArg (linePtr, argPtr, func, parens)
180 Boolean parens; /* TRUE if arg should be bounded by parens */
188 while (*cp != '(' && *cp != '\0') {
198 * No arguments whatsoever. Because 'make' and 'defined' aren't really
199 * "reserved words", we don't print a message. I think this is better
200 * than hitting the user with a warning message every time s/he uses
201 * the word 'make' or 'defined' at the beginning of a symbol...
207 while (*cp == ' ' || *cp == '\t') {
212 * Create a buffer for the argument and start it out at 16 characters
213 * long. Why 16? Why not?
217 while ((strchr(" \t)&|", *cp) == (char *)NULL) && (*cp != '\0')) {
220 * Parse the variable spec and install it as part of the argument
221 * if it's valid. We tell Var_Parse to complain on an undefined
222 * variable, so we don't do it too. Nor do we return an error,
223 * though perhaps we should...
229 cp2 = Var_Parse(cp, VAR_CMD, TRUE, &len, &doFree);
231 Buf_AddBytes(buf, strlen(cp2), (Byte *)cp2);
237 Buf_AddByte(buf, (Byte)*cp);
242 Buf_AddByte(buf, (Byte)'\0');
243 *argPtr = (char *)Buf_GetAll(buf, &argLen);
244 Buf_Destroy(buf, FALSE);
246 while (*cp == ' ' || *cp == '\t') {
249 if (parens && *cp != ')') {
250 Parse_Error (PARSE_WARNING, "Missing closing parenthesis for %s()",
255 * Advance pointer past close parenthesis.
265 *-----------------------------------------------------------------------
267 * Handle the 'defined' function for conditionals.
270 * TRUE if the given variable is defined.
275 *-----------------------------------------------------------------------
278 CondDoDefined (argLen, arg)
282 char savec = arg[argLen];
287 if (Var_Value (arg, VAR_CMD, &p1) != (char *)NULL) {
298 *-----------------------------------------------------------------------
300 * Front-end for Str_Match so it returns 0 on match and non-zero
301 * on mismatch. Callback function for CondDoMake via Lst_Find
304 * 0 if string matches pattern
309 *-----------------------------------------------------------------------
312 CondStrMatch(string, pattern)
316 return(!Str_Match((char *) string,(char *) pattern));
320 *-----------------------------------------------------------------------
322 * Handle the 'make' function for conditionals.
325 * TRUE if the given target is being made.
330 *-----------------------------------------------------------------------
333 CondDoMake (argLen, arg)
337 char savec = arg[argLen];
341 if (Lst_Find (create, (void *)arg, CondStrMatch) == NULL) {
351 *-----------------------------------------------------------------------
353 * See if the given file exists.
356 * TRUE if the file exists and FALSE if it does not.
361 *-----------------------------------------------------------------------
364 CondDoExists (argLen, arg)
368 char savec = arg[argLen];
373 path = Dir_FindFile(arg, dirSearchPath);
374 if (path != (char *)NULL) {
385 *-----------------------------------------------------------------------
387 * See if the given node exists and is an actual target.
390 * TRUE if the node exists as a target and FALSE if it does not.
395 *-----------------------------------------------------------------------
398 CondDoTarget (argLen, arg)
402 char savec = arg[argLen];
407 gn = Targ_FindNode(arg, TARG_NOCREATE);
408 if ((gn != NULL) && !OP_NOP(gn->type)) {
419 *-----------------------------------------------------------------------
421 * Convert the given number into a double. If the number begins
422 * with 0x, it is interpreted as a hexadecimal integer
423 * and converted to a double from there. All other strings just have
424 * strtod called on them.
427 * Sets 'value' to double value of string.
428 * Returns address of the first character after the last valid
429 * character of the converted number.
432 * Can change 'value' even if string is not a valid number.
435 *-----------------------------------------------------------------------
438 CondCvtArg(str, value)
442 if ((*str == '0') && (str[1] == 'x')) {
445 for (str += 2, i = 0; ; str++) {
447 if (isdigit((unsigned char) *str))
449 else if (isxdigit((unsigned char) *str))
450 x = 10 + *str - isupper((unsigned char) *str) ? 'A' : 'a';
460 *value = strtod(str, &eptr);
466 *-----------------------------------------------------------------------
468 * Return the next token from the input.
471 * A Token for the next lexical token in the stream.
474 * condPushback will be set back to None if it is used.
476 *-----------------------------------------------------------------------
484 if (condPushBack == None) {
485 while (*condExpr == ' ' || *condExpr == '\t') {
498 if (condExpr[1] == '|') {
505 if (condExpr[1] == '&') {
527 * Parse the variable spec and skip over it, saving its
531 lhs = Var_Parse(condExpr, VAR_CMD, doEval,&varSpecLen,&doFree);
532 if (lhs == var_Error) {
534 * Even if !doEval, we still report syntax errors, which
535 * is what getting var_Error back with !doEval means.
539 condExpr += varSpecLen;
541 if (!isspace((unsigned char) *condExpr) &&
542 strchr("!=><", *condExpr) == NULL) {
548 for (cp = lhs; *cp; cp++)
549 Buf_AddByte(buf, (Byte)*cp);
554 for (;*condExpr && !isspace((unsigned char) *condExpr);
556 Buf_AddByte(buf, (Byte)*condExpr);
558 Buf_AddByte(buf, (Byte)'\0');
559 lhs = (char *)Buf_GetAll(buf, &varSpecLen);
560 Buf_Destroy(buf, FALSE);
566 * Skip whitespace to get to the operator
568 while (isspace((unsigned char) *condExpr))
572 * Make sure the operator is a valid one. If it isn't a
573 * known relational operator, pretend we got a
582 if (condExpr[1] == '=') {
594 while (isspace((unsigned char) *condExpr)) {
597 if (*condExpr == '\0') {
598 Parse_Error(PARSE_WARNING,
599 "Missing right-hand-side of operator");
606 * Doing a string comparison. Only allow == and != for
615 if (((*op != '!') && (*op != '=')) || (op[1] != '=')) {
616 Parse_Error(PARSE_WARNING,
617 "String comparison operator should be either == or !=");
622 qt = *rhs == '"' ? 1 : 0;
625 ((qt && (*cp != '"')) ||
626 (!qt && strchr(" \t)", *cp) == NULL)) &&
627 (*cp != '\0'); cp++) {
628 if ((*cp == '\\') && (cp[1] != '\0')) {
630 * Backslash escapes things -- skip over next
631 * character, if it exists.
634 Buf_AddByte(buf, (Byte)*cp);
635 } else if (*cp == '$') {
639 cp2 = Var_Parse(cp, VAR_CMD, doEval,&len, &freeIt);
640 if (cp2 != var_Error) {
641 Buf_AddBytes(buf, strlen(cp2), (Byte *)cp2);
647 Buf_AddByte(buf, (Byte)*cp);
650 Buf_AddByte(buf, (Byte)*cp);
654 Buf_AddByte(buf, (Byte)0);
656 string = (char *)Buf_GetAll(buf, (int *)0);
657 Buf_Destroy(buf, FALSE);
659 DEBUGF(COND, ("lhs = \"%s\", rhs = \"%s\", op = %.2s\n",
662 * Null-terminate rhs and perform the comparison.
663 * t is set to the result.
666 t = strcmp(lhs, string) ? False : True;
668 t = strcmp(lhs, string) ? True : False;
671 if (rhs == condExpr) {
672 if (!qt && *cp == ')')
679 * rhs is either a float or an integer. Convert both the
680 * lhs and the rhs to a double and compare the two.
685 if (*CondCvtArg(lhs, &left) != '\0')
686 goto do_string_compare;
691 string = Var_Parse(rhs, VAR_CMD, doEval,&len,&freeIt);
692 if (string == var_Error) {
695 if (*CondCvtArg(string, &right) != '\0') {
698 goto do_string_compare;
706 char *c = CondCvtArg(rhs, &right);
708 goto do_string_compare;
709 if (rhs == condExpr) {
711 * Skip over the right-hand side
717 DEBUGF(COND, ("left = %f, right = %f, op = %.2s\n", left,
722 Parse_Error(PARSE_WARNING,
726 t = (left != right ? True : False);
730 Parse_Error(PARSE_WARNING,
734 t = (left == right ? True : False);
738 t = (left <= right ? True : False);
740 t = (left < right ? True : False);
745 t = (left >= right ? True : False);
747 t = (left > right ? True : False);
758 Boolean (*evalProc)(int, char *);
759 Boolean invert = FALSE;
763 if (strncmp (condExpr, "defined", 7) == 0) {
765 * Use CondDoDefined to evaluate the argument and
766 * CondGetArg to extract the argument from the 'function
769 evalProc = CondDoDefined;
771 arglen = CondGetArg (&condExpr, &arg, "defined", TRUE);
776 } else if (strncmp (condExpr, "make", 4) == 0) {
778 * Use CondDoMake to evaluate the argument and
779 * CondGetArg to extract the argument from the 'function
782 evalProc = CondDoMake;
784 arglen = CondGetArg (&condExpr, &arg, "make", TRUE);
789 } else if (strncmp (condExpr, "exists", 6) == 0) {
791 * Use CondDoExists to evaluate the argument and
792 * CondGetArg to extract the argument from the
795 evalProc = CondDoExists;
797 arglen = CondGetArg(&condExpr, &arg, "exists", TRUE);
802 } else if (strncmp(condExpr, "empty", 5) == 0) {
804 * Use Var_Parse to parse the spec in parens and return
805 * True if the resulting string is empty.
814 condExpr[arglen] != '(' && condExpr[arglen] != '\0';
818 if (condExpr[arglen] != '\0') {
819 val = Var_Parse(&condExpr[arglen - 1], VAR_CMD,
820 doEval, &length, &doFree);
821 if (val == var_Error) {
825 * A variable is empty when it just contains
826 * spaces... 4/15/92, christos
829 for (p = val; *p && isspace((unsigned char)*p); p++)
831 t = (*p == '\0') ? True : False;
837 * Advance condExpr to beyond the closing ). Note that
838 * we subtract one from arglen + length b/c length
839 * is calculated from condExpr[arglen - 1].
841 condExpr += arglen + length - 1;
847 } else if (strncmp (condExpr, "target", 6) == 0) {
849 * Use CondDoTarget to evaluate the argument and
850 * CondGetArg to extract the argument from the
853 evalProc = CondDoTarget;
855 arglen = CondGetArg(&condExpr, &arg, "target", TRUE);
862 * The symbol is itself the argument to the default
863 * function. We advance condExpr to the end of the symbol
864 * by hand (the next whitespace, closing paren or
865 * binary operator) and set to invert the evaluation
866 * function if condInvert is TRUE.
870 evalProc = condDefProc;
871 arglen = CondGetArg(&condExpr, &arg, "", FALSE);
875 * Evaluate the argument using the set function. If invert
876 * is TRUE, we invert the sense of the function.
878 t = (!doEval || (* evalProc) (arglen, arg) ?
879 (invert ? False : True) :
880 (invert ? True : False));
893 *-----------------------------------------------------------------------
895 * Parse a single term in the expression. This consists of a terminal
896 * symbol or Not and a terminal symbol (not including the binary
898 * T -> defined(variable) | make(target) | exists(file) | symbol
902 * True, False or Err.
905 * Tokens are consumed.
907 *-----------------------------------------------------------------------
915 t = CondToken(doEval);
917 if (t == EndOfFile) {
919 * If we reached the end of the expression, the expression
923 } else if (t == LParen) {
929 if (CondToken(doEval) != RParen) {
933 } else if (t == Not) {
937 } else if (t == False) {
945 *-----------------------------------------------------------------------
947 * Parse a conjunctive factor (nice name, wot?)
954 * Tokens are consumed.
956 *-----------------------------------------------------------------------
966 o = CondToken(doEval);
972 * If T is False, the whole thing will be False, but we have to
973 * parse the r.h.s. anyway (to throw it away).
974 * If T is True, the result is the r.h.s., be it an Err or no.
992 *-----------------------------------------------------------------------
994 * Main expression production.
998 * True, False or Err.
1001 * Tokens are, of course, consumed.
1003 *-----------------------------------------------------------------------
1013 o = CondToken(doEval);
1019 * A similar thing occurs for ||, except that here we make sure
1020 * the l.h.s. is False before we bother to evaluate the r.h.s.
1021 * Once again, if l is False, the result is the r.h.s. and once
1022 * again if l is True, we parse the r.h.s. to throw it away.
1027 (void) CondE(FALSE);
1040 *-----------------------------------------------------------------------
1042 * Evaluate the conditional in the passed line. The line
1044 * #<cond-type> <expr>
1045 * where <cond-type> is any of if, ifmake, ifnmake, ifdef,
1046 * ifndef, elif, elifmake, elifnmake, elifdef, elifndef
1047 * and <expr> consists of &&, ||, !, make(target), defined(variable)
1048 * and parenthetical groupings thereof.
1051 * COND_PARSE if should parse lines after the conditional
1052 * COND_SKIP if should skip lines after the conditional
1053 * COND_INVALID if not a valid conditional.
1058 *-----------------------------------------------------------------------
1062 char *line; /* Line to parse */
1066 Boolean value = FALSE;
1067 int level; /* Level at which to report errors. */
1069 level = PARSE_FATAL;
1071 for (line++; *line == ' ' || *line == '\t'; line++) {
1076 * Find what type of if we're dealing with. The result is left
1077 * in ifp and isElse is set TRUE if it's an elif line.
1079 if (line[0] == 'e' && line[1] == 'l') {
1082 } else if (strncmp (line, "endif", 5) == 0) {
1084 * End of a conditional section. If skipIfLevel is non-zero, that
1085 * conditional was skipped, so lines following it should also be
1086 * skipped. Hence, we return COND_SKIP. Otherwise, the conditional
1087 * was read so succeeding lines should be parsed (think about it...)
1088 * so we return COND_PARSE, unless this endif isn't paired with
1091 if (skipIfLevel != 0) {
1095 if (condTop == MAXIF) {
1096 Parse_Error (level, "if-less endif");
1097 return (COND_INVALID);
1101 return (COND_PARSE);
1109 * Figure out what sort of conditional it is -- what its default
1110 * function is, etc. -- by looking in the table of valid "ifs"
1112 for (ifp = ifs; ifp->form != (char *)0; ifp++) {
1113 if (strncmp (ifp->form, line, ifp->formlen) == 0) {
1118 if (ifp->form == (char *) 0) {
1120 * Nothing fit. If the first word on the line is actually
1121 * "else", it's a valid conditional whose value is the inverse
1122 * of the previous if we parsed.
1124 if (isElse && (line[0] == 's') && (line[1] == 'e')) {
1125 if (condTop == MAXIF) {
1126 Parse_Error (level, "if-less else");
1127 return (COND_INVALID);
1128 } else if (skipIfLevel == 0) {
1129 value = !condStack[condTop];
1135 * Not a valid conditional type. No error...
1137 return (COND_INVALID);
1141 if (condTop == MAXIF) {
1142 Parse_Error (level, "if-less elif");
1143 return (COND_INVALID);
1144 } else if (skipIfLevel != 0) {
1146 * If skipping this conditional, just ignore the whole thing.
1147 * If we don't, the user might be employing a variable that's
1148 * undefined, for which there's an enclosing ifdef that
1153 } else if (skipLine) {
1155 * Don't even try to evaluate a conditional that's not an else if
1156 * we're skipping things...
1163 * Initialize file-global variables for parsing
1165 condDefProc = ifp->defProc;
1166 condInvert = ifp->doNot;
1168 line += ifp->formlen;
1170 while (*line == ' ' || *line == '\t') {
1175 condPushBack = None;
1177 switch (CondE(TRUE)) {
1179 if (CondToken(TRUE) == EndOfFile) {
1186 if (CondToken(TRUE) == EndOfFile) {
1193 Parse_Error (level, "Malformed conditional (%s)",
1195 return (COND_INVALID);
1202 } else if ((skipIfLevel != 0) || condStack[condTop]) {
1204 * If this is an else-type conditional, it should only take effect
1205 * if its corresponding if was evaluated and FALSE. If its if was
1206 * TRUE or skipped, we return COND_SKIP (and start skipping in case
1207 * we weren't already), leaving the stack unmolested so later elif's
1216 * This is the one case where we can definitely proclaim a fatal
1217 * error. If we don't, we're hosed.
1219 Parse_Error (PARSE_FATAL, "Too many nested if's. %d max.", MAXIF);
1220 return (COND_INVALID);
1222 condStack[condTop] = value;
1224 return (value ? COND_PARSE : COND_SKIP);
1229 *-----------------------------------------------------------------------
1231 * Make sure everything's clean at the end of a makefile.
1237 * Parse_Error will be called if open conditionals are around.
1239 *-----------------------------------------------------------------------
1244 if (condTop != MAXIF) {
1245 Parse_Error(PARSE_FATAL, "%d open conditional%s", MAXIF-condTop,
1246 MAXIF-condTop == 1 ? "" : "s");