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-rw-r--r--usr.bin/make/cond.c1247
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diff --git a/usr.bin/make/cond.c b/usr.bin/make/cond.c
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+++ b/usr.bin/make/cond.c
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+/*
+ * Copyright (c) 1988, 1989, 1990, 1993
+ * The Regents of the University of California. All rights reserved.
+ * Copyright (c) 1989 by Berkeley Softworks
+ * All rights reserved.
+ *
+ * This code is derived from software contributed to Berkeley by
+ * Adam de Boor.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ * 1. Redistributions of source code must retain the above copyright
+ * notice, this list of conditions and the following disclaimer.
+ * 2. Redistributions in binary form must reproduce the above copyright
+ * notice, this list of conditions and the following disclaimer in the
+ * documentation and/or other materials provided with the distribution.
+ * 3. All advertising materials mentioning features or use of this software
+ * must display the following acknowledgement:
+ * This product includes software developed by the University of
+ * California, Berkeley and its contributors.
+ * 4. Neither the name of the University nor the names of its contributors
+ * may be used to endorse or promote products derived from this software
+ * without specific prior written permission.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
+ * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
+ * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
+ * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
+ * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
+ * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
+ * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
+ * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
+ * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
+ * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
+ * SUCH DAMAGE.
+ */
+
+#ifndef lint
+static char sccsid[] = "@(#)cond.c 8.2 (Berkeley) 1/2/94";
+#endif /* not lint */
+
+/*-
+ * cond.c --
+ * Functions to handle conditionals in a makefile.
+ *
+ * Interface:
+ * Cond_Eval Evaluate the conditional in the passed line.
+ *
+ */
+
+#include <ctype.h>
+#include <math.h>
+#include "make.h"
+#include "hash.h"
+#include "dir.h"
+#include "buf.h"
+
+/*
+ * The parsing of conditional expressions is based on this grammar:
+ * E -> F || E
+ * E -> F
+ * F -> T && F
+ * F -> T
+ * T -> defined(variable)
+ * T -> make(target)
+ * T -> exists(file)
+ * T -> empty(varspec)
+ * T -> target(name)
+ * T -> symbol
+ * T -> $(varspec) op value
+ * T -> $(varspec) == "string"
+ * T -> $(varspec) != "string"
+ * T -> ( E )
+ * T -> ! T
+ * op -> == | != | > | < | >= | <=
+ *
+ * 'symbol' is some other symbol to which the default function (condDefProc)
+ * is applied.
+ *
+ * Tokens are scanned from the 'condExpr' string. The scanner (CondToken)
+ * will return And for '&' and '&&', Or for '|' and '||', Not for '!',
+ * LParen for '(', RParen for ')' and will evaluate the other terminal
+ * symbols, using either the default function or the function given in the
+ * terminal, and return the result as either True or False.
+ *
+ * All Non-Terminal functions (CondE, CondF and CondT) return Err on error.
+ */
+typedef enum {
+ And, Or, Not, True, False, LParen, RParen, EndOfFile, None, Err
+} Token;
+
+/*-
+ * Structures to handle elegantly the different forms of #if's. The
+ * last two fields are stored in condInvert and condDefProc, respectively.
+ */
+static int CondGetArg __P((char **, char **, char *, Boolean));
+static Boolean CondDoDefined __P((int, char *));
+static int CondStrMatch __P((char *, char *));
+static Boolean CondDoMake __P((int, char *));
+static Boolean CondDoExists __P((int, char *));
+static Boolean CondDoTarget __P((int, char *));
+static Boolean CondCvtArg __P((char *, double *));
+static Token CondToken __P((Boolean));
+static Token CondT __P((Boolean));
+static Token CondF __P((Boolean));
+static Token CondE __P((Boolean));
+
+static struct If {
+ char *form; /* Form of if */
+ int formlen; /* Length of form */
+ Boolean doNot; /* TRUE if default function should be negated */
+ Boolean (*defProc)(); /* Default function to apply */
+} ifs[] = {
+ { "ifdef", 5, FALSE, CondDoDefined },
+ { "ifndef", 6, TRUE, CondDoDefined },
+ { "ifmake", 6, FALSE, CondDoMake },
+ { "ifnmake", 7, TRUE, CondDoMake },
+ { "if", 2, FALSE, CondDoDefined },
+ { (char *)0, 0, FALSE, (Boolean (*)())0 }
+};
+
+static Boolean condInvert; /* Invert the default function */
+static Boolean (*condDefProc)(); /* Default function to apply */
+static char *condExpr; /* The expression to parse */
+static Token condPushBack=None; /* Single push-back token used in
+ * parsing */
+
+#define MAXIF 30 /* greatest depth of #if'ing */
+
+static Boolean condStack[MAXIF]; /* Stack of conditionals's values */
+static int condTop = MAXIF; /* Top-most conditional */
+static int skipIfLevel=0; /* Depth of skipped conditionals */
+static Boolean skipLine = FALSE; /* Whether the parse module is skipping
+ * lines */
+
+/*-
+ *-----------------------------------------------------------------------
+ * CondPushBack --
+ * Push back the most recent token read. We only need one level of
+ * this, so the thing is just stored in 'condPushback'.
+ *
+ * Results:
+ * None.
+ *
+ * Side Effects:
+ * condPushback is overwritten.
+ *
+ *-----------------------------------------------------------------------
+ */
+static void
+CondPushBack (t)
+ Token t; /* Token to push back into the "stream" */
+{
+ condPushBack = t;
+}
+
+/*-
+ *-----------------------------------------------------------------------
+ * CondGetArg --
+ * Find the argument of a built-in function.
+ *
+ * Results:
+ * The length of the argument and the address of the argument.
+ *
+ * Side Effects:
+ * The pointer is set to point to the closing parenthesis of the
+ * function call.
+ *
+ *-----------------------------------------------------------------------
+ */
+static int
+CondGetArg (linePtr, argPtr, func, parens)
+ char **linePtr;
+ char **argPtr;
+ char *func;
+ Boolean parens; /* TRUE if arg should be bounded by parens */
+{
+ register char *cp;
+ int argLen;
+ register Buffer buf;
+
+ cp = *linePtr;
+ if (parens) {
+ while (*cp != '(' && *cp != '\0') {
+ cp++;
+ }
+ if (*cp == '(') {
+ cp++;
+ }
+ }
+
+ if (*cp == '\0') {
+ /*
+ * No arguments whatsoever. Because 'make' and 'defined' aren't really
+ * "reserved words", we don't print a message. I think this is better
+ * than hitting the user with a warning message every time s/he uses
+ * the word 'make' or 'defined' at the beginning of a symbol...
+ */
+ *argPtr = cp;
+ return (0);
+ }
+
+ while (*cp == ' ' || *cp == '\t') {
+ cp++;
+ }
+
+ /*
+ * Create a buffer for the argument and start it out at 16 characters
+ * long. Why 16? Why not?
+ */
+ buf = Buf_Init(16);
+
+ while ((strchr(" \t)&|", *cp) == (char *)NULL) && (*cp != '\0')) {
+ if (*cp == '$') {
+ /*
+ * Parse the variable spec and install it as part of the argument
+ * if it's valid. We tell Var_Parse to complain on an undefined
+ * variable, so we don't do it too. Nor do we return an error,
+ * though perhaps we should...
+ */
+ char *cp2;
+ int len;
+ Boolean doFree;
+
+ cp2 = Var_Parse(cp, VAR_CMD, TRUE, &len, &doFree);
+
+ Buf_AddBytes(buf, strlen(cp2), (Byte *)cp2);
+ if (doFree) {
+ free(cp2);
+ }
+ cp += len;
+ } else {
+ Buf_AddByte(buf, (Byte)*cp);
+ cp++;
+ }
+ }
+
+ Buf_AddByte(buf, (Byte)'\0');
+ *argPtr = (char *)Buf_GetAll(buf, &argLen);
+ Buf_Destroy(buf, FALSE);
+
+ while (*cp == ' ' || *cp == '\t') {
+ cp++;
+ }
+ if (parens && *cp != ')') {
+ Parse_Error (PARSE_WARNING, "Missing closing parenthesis for %s()",
+ func);
+ return (0);
+ } else if (parens) {
+ /*
+ * Advance pointer past close parenthesis.
+ */
+ cp++;
+ }
+
+ *linePtr = cp;
+ return (argLen);
+}
+
+/*-
+ *-----------------------------------------------------------------------
+ * CondDoDefined --
+ * Handle the 'defined' function for conditionals.
+ *
+ * Results:
+ * TRUE if the given variable is defined.
+ *
+ * Side Effects:
+ * None.
+ *
+ *-----------------------------------------------------------------------
+ */
+static Boolean
+CondDoDefined (argLen, arg)
+ int argLen;
+ char *arg;
+{
+ char savec = arg[argLen];
+ Boolean result;
+
+ arg[argLen] = '\0';
+ if (Var_Value (arg, VAR_CMD) != (char *)NULL) {
+ result = TRUE;
+ } else {
+ result = FALSE;
+ }
+ arg[argLen] = savec;
+ return (result);
+}
+
+/*-
+ *-----------------------------------------------------------------------
+ * CondStrMatch --
+ * Front-end for Str_Match so it returns 0 on match and non-zero
+ * on mismatch. Callback function for CondDoMake via Lst_Find
+ *
+ * Results:
+ * 0 if string matches pattern
+ *
+ * Side Effects:
+ * None
+ *
+ *-----------------------------------------------------------------------
+ */
+static int
+CondStrMatch(string, pattern)
+ char *string;
+ char *pattern;
+{
+ return(!Str_Match(string,pattern));
+}
+
+/*-
+ *-----------------------------------------------------------------------
+ * CondDoMake --
+ * Handle the 'make' function for conditionals.
+ *
+ * Results:
+ * TRUE if the given target is being made.
+ *
+ * Side Effects:
+ * None.
+ *
+ *-----------------------------------------------------------------------
+ */
+static Boolean
+CondDoMake (argLen, arg)
+ int argLen;
+ char *arg;
+{
+ char savec = arg[argLen];
+ Boolean result;
+
+ arg[argLen] = '\0';
+ if (Lst_Find (create, (ClientData)arg, CondStrMatch) == NILLNODE) {
+ result = FALSE;
+ } else {
+ result = TRUE;
+ }
+ arg[argLen] = savec;
+ return (result);
+}
+
+/*-
+ *-----------------------------------------------------------------------
+ * CondDoExists --
+ * See if the given file exists.
+ *
+ * Results:
+ * TRUE if the file exists and FALSE if it does not.
+ *
+ * Side Effects:
+ * None.
+ *
+ *-----------------------------------------------------------------------
+ */
+static Boolean
+CondDoExists (argLen, arg)
+ int argLen;
+ char *arg;
+{
+ char savec = arg[argLen];
+ Boolean result;
+ char *path;
+
+ arg[argLen] = '\0';
+ path = Dir_FindFile(arg, dirSearchPath);
+ if (path != (char *)NULL) {
+ result = TRUE;
+ free(path);
+ } else {
+ result = FALSE;
+ }
+ arg[argLen] = savec;
+ return (result);
+}
+
+/*-
+ *-----------------------------------------------------------------------
+ * CondDoTarget --
+ * See if the given node exists and is an actual target.
+ *
+ * Results:
+ * TRUE if the node exists as a target and FALSE if it does not.
+ *
+ * Side Effects:
+ * None.
+ *
+ *-----------------------------------------------------------------------
+ */
+static Boolean
+CondDoTarget (argLen, arg)
+ int argLen;
+ char *arg;
+{
+ char savec = arg[argLen];
+ Boolean result;
+ GNode *gn;
+
+ arg[argLen] = '\0';
+ gn = Targ_FindNode(arg, TARG_NOCREATE);
+ if ((gn != NILGNODE) && !OP_NOP(gn->type)) {
+ result = TRUE;
+ } else {
+ result = FALSE;
+ }
+ arg[argLen] = savec;
+ return (result);
+}
+
+
+/*-
+ *-----------------------------------------------------------------------
+ * CondCvtArg --
+ * Convert the given number into a double. If the number begins
+ * with 0x, it is interpreted as a hexadecimal integer
+ * and converted to a double from there. All other strings just have
+ * strtod called on them.
+ *
+ * Results:
+ * Sets 'value' to double value of string.
+ * Returns true if the string was a valid number, false o.w.
+ *
+ * Side Effects:
+ * Can change 'value' even if string is not a valid number.
+ *
+ *
+ *-----------------------------------------------------------------------
+ */
+static Boolean
+CondCvtArg(str, value)
+ register char *str;
+ double *value;
+{
+ if ((*str == '0') && (str[1] == 'x')) {
+ register long i;
+
+ for (str += 2, i = 0; *str; str++) {
+ int x;
+ if (isdigit((unsigned char) *str))
+ x = *str - '0';
+ else if (isxdigit((unsigned char) *str))
+ x = 10 + *str - isupper((unsigned char) *str) ? 'A' : 'a';
+ else
+ return FALSE;
+ i = (i << 4) + x;
+ }
+ *value = (double) i;
+ return TRUE;
+ }
+ else {
+ char *eptr;
+ *value = strtod(str, &eptr);
+ return *eptr == '\0';
+ }
+}
+
+/*-
+ *-----------------------------------------------------------------------
+ * CondToken --
+ * Return the next token from the input.
+ *
+ * Results:
+ * A Token for the next lexical token in the stream.
+ *
+ * Side Effects:
+ * condPushback will be set back to None if it is used.
+ *
+ *-----------------------------------------------------------------------
+ */
+static Token
+CondToken(doEval)
+ Boolean doEval;
+{
+ Token t;
+
+ if (condPushBack == None) {
+ while (*condExpr == ' ' || *condExpr == '\t') {
+ condExpr++;
+ }
+ switch (*condExpr) {
+ case '(':
+ t = LParen;
+ condExpr++;
+ break;
+ case ')':
+ t = RParen;
+ condExpr++;
+ break;
+ case '|':
+ if (condExpr[1] == '|') {
+ condExpr++;
+ }
+ condExpr++;
+ t = Or;
+ break;
+ case '&':
+ if (condExpr[1] == '&') {
+ condExpr++;
+ }
+ condExpr++;
+ t = And;
+ break;
+ case '!':
+ t = Not;
+ condExpr++;
+ break;
+ case '\n':
+ case '\0':
+ t = EndOfFile;
+ break;
+ case '$': {
+ char *lhs;
+ char *rhs;
+ char *op;
+ int varSpecLen;
+ Boolean doFree;
+
+ /*
+ * Parse the variable spec and skip over it, saving its
+ * value in lhs.
+ */
+ t = Err;
+ lhs = Var_Parse(condExpr, VAR_CMD, doEval,&varSpecLen,&doFree);
+ if (lhs == var_Error) {
+ /*
+ * Even if !doEval, we still report syntax errors, which
+ * is what getting var_Error back with !doEval means.
+ */
+ return(Err);
+ }
+ condExpr += varSpecLen;
+
+ if (!isspace(*condExpr) && strchr("!=><", *condExpr) == NULL) {
+ Buffer buf;
+ char *cp;
+
+ buf = Buf_Init(0);
+
+ for (cp = lhs; *cp; cp++)
+ Buf_AddByte(buf, (Byte)*cp);
+
+ if (doFree)
+ free(lhs);
+
+ for (;*condExpr && !isspace(*condExpr); condExpr++)
+ Buf_AddByte(buf, (Byte)*condExpr);
+
+ Buf_AddByte(buf, (Byte)'\0');
+ lhs = (char *)Buf_GetAll(buf, &varSpecLen);
+ Buf_Destroy(buf, FALSE);
+
+ doFree = TRUE;
+ }
+
+ /*
+ * Skip whitespace to get to the operator
+ */
+ while (isspace(*condExpr))
+ condExpr++;
+
+ /*
+ * Make sure the operator is a valid one. If it isn't a
+ * known relational operator, pretend we got a
+ * != 0 comparison.
+ */
+ op = condExpr;
+ switch (*condExpr) {
+ case '!':
+ case '=':
+ case '<':
+ case '>':
+ if (condExpr[1] == '=') {
+ condExpr += 2;
+ } else {
+ condExpr += 1;
+ }
+ break;
+ default:
+ op = "!=";
+ rhs = "0";
+
+ goto do_compare;
+ }
+ while (isspace(*condExpr)) {
+ condExpr++;
+ }
+ if (*condExpr == '\0') {
+ Parse_Error(PARSE_WARNING,
+ "Missing right-hand-side of operator");
+ goto error;
+ }
+ rhs = condExpr;
+do_compare:
+ if (*rhs == '"') {
+ /*
+ * Doing a string comparison. Only allow == and != for
+ * operators.
+ */
+ char *string;
+ char *cp, *cp2;
+ int qt;
+ Buffer buf;
+
+do_string_compare:
+ if (((*op != '!') && (*op != '=')) || (op[1] != '=')) {
+ Parse_Error(PARSE_WARNING,
+ "String comparison operator should be either == or !=");
+ goto error;
+ }
+
+ buf = Buf_Init(0);
+ qt = *rhs == '"' ? 1 : 0;
+
+ for (cp = &rhs[qt];
+ ((qt && (*cp != '"')) ||
+ (!qt && strchr(" \t)", *cp) == NULL)) &&
+ (*cp != '\0'); cp++) {
+ if ((*cp == '\\') && (cp[1] != '\0')) {
+ /*
+ * Backslash escapes things -- skip over next
+ * character, if it exists.
+ */
+ cp++;
+ Buf_AddByte(buf, (Byte)*cp);
+ } else if (*cp == '$') {
+ int len;
+ Boolean freeIt;
+
+ cp2 = Var_Parse(cp, VAR_CMD, doEval,&len, &freeIt);
+ if (cp2 != var_Error) {
+ Buf_AddBytes(buf, strlen(cp2), (Byte *)cp2);
+ if (freeIt) {
+ free(cp2);
+ }
+ cp += len - 1;
+ } else {
+ Buf_AddByte(buf, (Byte)*cp);
+ }
+ } else {
+ Buf_AddByte(buf, (Byte)*cp);
+ }
+ }
+
+ Buf_AddByte(buf, (Byte)0);
+
+ string = (char *)Buf_GetAll(buf, (int *)0);
+ Buf_Destroy(buf, FALSE);
+
+ if (DEBUG(COND)) {
+ printf("lhs = \"%s\", rhs = \"%s\", op = %.2s\n",
+ lhs, string, op);
+ }
+ /*
+ * Null-terminate rhs and perform the comparison.
+ * t is set to the result.
+ */
+ if (*op == '=') {
+ t = strcmp(lhs, string) ? False : True;
+ } else {
+ t = strcmp(lhs, string) ? True : False;
+ }
+ free(string);
+ if (rhs == condExpr) {
+ if (!qt && *cp == ')')
+ condExpr = cp;
+ else
+ condExpr = cp + 1;
+ }
+ } else {
+ /*
+ * rhs is either a float or an integer. Convert both the
+ * lhs and the rhs to a double and compare the two.
+ */
+ double left, right;
+ char *string;
+
+ if (!CondCvtArg(lhs, &left))
+ goto do_string_compare;
+ if (*rhs == '$') {
+ int len;
+ Boolean freeIt;
+
+ string = Var_Parse(rhs, VAR_CMD, doEval,&len,&freeIt);
+ if (string == var_Error) {
+ right = 0.0;
+ } else {
+ if (!CondCvtArg(string, &right)) {
+ if (freeIt)
+ free(string);
+ goto do_string_compare;
+ }
+ if (freeIt)
+ free(string);
+ if (rhs == condExpr)
+ condExpr += len;
+ }
+ } else {
+ if (!CondCvtArg(rhs, &right))
+ goto do_string_compare;
+ if (rhs == condExpr) {
+ /*
+ * Skip over the right-hand side
+ */
+ while(!isspace(*condExpr) && (*condExpr != '\0')) {
+ condExpr++;
+ }
+ }
+ }
+
+ if (DEBUG(COND)) {
+ printf("left = %f, right = %f, op = %.2s\n", left,
+ right, op);
+ }
+ switch(op[0]) {
+ case '!':
+ if (op[1] != '=') {
+ Parse_Error(PARSE_WARNING,
+ "Unknown operator");
+ goto error;
+ }
+ t = (left != right ? True : False);
+ break;
+ case '=':
+ if (op[1] != '=') {
+ Parse_Error(PARSE_WARNING,
+ "Unknown operator");
+ goto error;
+ }
+ t = (left == right ? True : False);
+ break;
+ case '<':
+ if (op[1] == '=') {
+ t = (left <= right ? True : False);
+ } else {
+ t = (left < right ? True : False);
+ }
+ break;
+ case '>':
+ if (op[1] == '=') {
+ t = (left >= right ? True : False);
+ } else {
+ t = (left > right ? True : False);
+ }
+ break;
+ }
+ }
+error:
+ if (doFree)
+ free(lhs);
+ break;
+ }
+ default: {
+ Boolean (*evalProc)();
+ Boolean invert = FALSE;
+ char *arg;
+ int arglen;
+
+ if (strncmp (condExpr, "defined", 7) == 0) {
+ /*
+ * Use CondDoDefined to evaluate the argument and
+ * CondGetArg to extract the argument from the 'function
+ * call'.
+ */
+ evalProc = CondDoDefined;
+ condExpr += 7;
+ arglen = CondGetArg (&condExpr, &arg, "defined", TRUE);
+ if (arglen == 0) {
+ condExpr -= 7;
+ goto use_default;
+ }
+ } else if (strncmp (condExpr, "make", 4) == 0) {
+ /*
+ * Use CondDoMake to evaluate the argument and
+ * CondGetArg to extract the argument from the 'function
+ * call'.
+ */
+ evalProc = CondDoMake;
+ condExpr += 4;
+ arglen = CondGetArg (&condExpr, &arg, "make", TRUE);
+ if (arglen == 0) {
+ condExpr -= 4;
+ goto use_default;
+ }
+ } else if (strncmp (condExpr, "exists", 6) == 0) {
+ /*
+ * Use CondDoExists to evaluate the argument and
+ * CondGetArg to extract the argument from the
+ * 'function call'.
+ */
+ evalProc = CondDoExists;
+ condExpr += 6;
+ arglen = CondGetArg(&condExpr, &arg, "exists", TRUE);
+ if (arglen == 0) {
+ condExpr -= 6;
+ goto use_default;
+ }
+ } else if (strncmp(condExpr, "empty", 5) == 0) {
+ /*
+ * Use Var_Parse to parse the spec in parens and return
+ * True if the resulting string is empty.
+ */
+ int length;
+ Boolean doFree;
+ char *val;
+
+ condExpr += 5;
+
+ for (arglen = 0;
+ condExpr[arglen] != '(' && condExpr[arglen] != '\0';
+ arglen += 1)
+ {
+ /* void */ ;
+ }
+ if (condExpr[arglen] != '\0') {
+ val = Var_Parse(&condExpr[arglen - 1], VAR_CMD,
+ doEval, &length, &doFree);
+ if (val == var_Error) {
+ t = Err;
+ } else {
+ /*
+ * A variable is empty when it just contains
+ * spaces... 4/15/92, christos
+ */
+ char *p;
+ for (p = val; *p && isspace(*p); p++)
+ continue;
+ t = (*p == '\0') ? True : False;
+ }
+ if (doFree) {
+ free(val);
+ }
+ /*
+ * Advance condExpr to beyond the closing ). Note that
+ * we subtract one from arglen + length b/c length
+ * is calculated from condExpr[arglen - 1].
+ */
+ condExpr += arglen + length - 1;
+ } else {
+ condExpr -= 5;
+ goto use_default;
+ }
+ break;
+ } else if (strncmp (condExpr, "target", 6) == 0) {
+ /*
+ * Use CondDoTarget to evaluate the argument and
+ * CondGetArg to extract the argument from the
+ * 'function call'.
+ */
+ evalProc = CondDoTarget;
+ condExpr += 6;
+ arglen = CondGetArg(&condExpr, &arg, "target", TRUE);
+ if (arglen == 0) {
+ condExpr -= 6;
+ goto use_default;
+ }
+ } else {
+ /*
+ * The symbol is itself the argument to the default
+ * function. We advance condExpr to the end of the symbol
+ * by hand (the next whitespace, closing paren or
+ * binary operator) and set to invert the evaluation
+ * function if condInvert is TRUE.
+ */
+ use_default:
+ invert = condInvert;
+ evalProc = condDefProc;
+ arglen = CondGetArg(&condExpr, &arg, "", FALSE);
+ }
+
+ /*
+ * Evaluate the argument using the set function. If invert
+ * is TRUE, we invert the sense of the function.
+ */
+ t = (!doEval || (* evalProc) (arglen, arg) ?
+ (invert ? False : True) :
+ (invert ? True : False));
+ free(arg);
+ break;
+ }
+ }
+ } else {
+ t = condPushBack;
+ condPushBack = None;
+ }
+ return (t);
+}
+
+/*-
+ *-----------------------------------------------------------------------
+ * CondT --
+ * Parse a single term in the expression. This consists of a terminal
+ * symbol or Not and a terminal symbol (not including the binary
+ * operators):
+ * T -> defined(variable) | make(target) | exists(file) | symbol
+ * T -> ! T | ( E )
+ *
+ * Results:
+ * True, False or Err.
+ *
+ * Side Effects:
+ * Tokens are consumed.
+ *
+ *-----------------------------------------------------------------------
+ */
+static Token
+CondT(doEval)
+ Boolean doEval;
+{
+ Token t;
+
+ t = CondToken(doEval);
+
+ if (t == EndOfFile) {
+ /*
+ * If we reached the end of the expression, the expression
+ * is malformed...
+ */
+ t = Err;
+ } else if (t == LParen) {
+ /*
+ * T -> ( E )
+ */
+ t = CondE(doEval);
+ if (t != Err) {
+ if (CondToken(doEval) != RParen) {
+ t = Err;
+ }
+ }
+ } else if (t == Not) {
+ t = CondT(doEval);
+ if (t == True) {
+ t = False;
+ } else if (t == False) {
+ t = True;
+ }
+ }
+ return (t);
+}
+
+/*-
+ *-----------------------------------------------------------------------
+ * CondF --
+ * Parse a conjunctive factor (nice name, wot?)
+ * F -> T && F | T
+ *
+ * Results:
+ * True, False or Err
+ *
+ * Side Effects:
+ * Tokens are consumed.
+ *
+ *-----------------------------------------------------------------------
+ */
+static Token
+CondF(doEval)
+ Boolean doEval;
+{
+ Token l, o;
+
+ l = CondT(doEval);
+ if (l != Err) {
+ o = CondToken(doEval);
+
+ if (o == And) {
+ /*
+ * F -> T && F
+ *
+ * If T is False, the whole thing will be False, but we have to
+ * parse the r.h.s. anyway (to throw it away).
+ * If T is True, the result is the r.h.s., be it an Err or no.
+ */
+ if (l == True) {
+ l = CondF(doEval);
+ } else {
+ (void) CondF(FALSE);
+ }
+ } else {
+ /*
+ * F -> T
+ */
+ CondPushBack (o);
+ }
+ }
+ return (l);
+}
+
+/*-
+ *-----------------------------------------------------------------------
+ * CondE --
+ * Main expression production.
+ * E -> F || E | F
+ *
+ * Results:
+ * True, False or Err.
+ *
+ * Side Effects:
+ * Tokens are, of course, consumed.
+ *
+ *-----------------------------------------------------------------------
+ */
+static Token
+CondE(doEval)
+ Boolean doEval;
+{
+ Token l, o;
+
+ l = CondF(doEval);
+ if (l != Err) {
+ o = CondToken(doEval);
+
+ if (o == Or) {
+ /*
+ * E -> F || E
+ *
+ * A similar thing occurs for ||, except that here we make sure
+ * the l.h.s. is False before we bother to evaluate the r.h.s.
+ * Once again, if l is False, the result is the r.h.s. and once
+ * again if l is True, we parse the r.h.s. to throw it away.
+ */
+ if (l == False) {
+ l = CondE(doEval);
+ } else {
+ (void) CondE(FALSE);
+ }
+ } else {
+ /*
+ * E -> F
+ */
+ CondPushBack (o);
+ }
+ }
+ return (l);
+}
+
+/*-
+ *-----------------------------------------------------------------------
+ * Cond_Eval --
+ * Evaluate the conditional in the passed line. The line
+ * looks like this:
+ * #<cond-type> <expr>
+ * where <cond-type> is any of if, ifmake, ifnmake, ifdef,
+ * ifndef, elif, elifmake, elifnmake, elifdef, elifndef
+ * and <expr> consists of &&, ||, !, make(target), defined(variable)
+ * and parenthetical groupings thereof.
+ *
+ * Results:
+ * COND_PARSE if should parse lines after the conditional
+ * COND_SKIP if should skip lines after the conditional
+ * COND_INVALID if not a valid conditional.
+ *
+ * Side Effects:
+ * None.
+ *
+ *-----------------------------------------------------------------------
+ */
+int
+Cond_Eval (line)
+ char *line; /* Line to parse */
+{
+ struct If *ifp;
+ Boolean isElse;
+ Boolean value = FALSE;
+ int level; /* Level at which to report errors. */
+
+ level = PARSE_FATAL;
+
+ for (line++; *line == ' ' || *line == '\t'; line++) {
+ continue;
+ }
+
+ /*
+ * Find what type of if we're dealing with. The result is left
+ * in ifp and isElse is set TRUE if it's an elif line.
+ */
+ if (line[0] == 'e' && line[1] == 'l') {
+ line += 2;
+ isElse = TRUE;
+ } else if (strncmp (line, "endif", 5) == 0) {
+ /*
+ * End of a conditional section. If skipIfLevel is non-zero, that
+ * conditional was skipped, so lines following it should also be
+ * skipped. Hence, we return COND_SKIP. Otherwise, the conditional
+ * was read so succeeding lines should be parsed (think about it...)
+ * so we return COND_PARSE, unless this endif isn't paired with
+ * a decent if.
+ */
+ if (skipIfLevel != 0) {
+ skipIfLevel -= 1;
+ return (COND_SKIP);
+ } else {
+ if (condTop == MAXIF) {
+ Parse_Error (level, "if-less endif");
+ return (COND_INVALID);
+ } else {
+ skipLine = FALSE;
+ condTop += 1;
+ return (COND_PARSE);
+ }
+ }
+ } else {
+ isElse = FALSE;
+ }
+
+ /*
+ * Figure out what sort of conditional it is -- what its default
+ * function is, etc. -- by looking in the table of valid "ifs"
+ */
+ for (ifp = ifs; ifp->form != (char *)0; ifp++) {
+ if (strncmp (ifp->form, line, ifp->formlen) == 0) {
+ break;
+ }
+ }
+
+ if (ifp->form == (char *) 0) {
+ /*
+ * Nothing fit. If the first word on the line is actually
+ * "else", it's a valid conditional whose value is the inverse
+ * of the previous if we parsed.
+ */
+ if (isElse && (line[0] == 's') && (line[1] == 'e')) {
+ if (condTop == MAXIF) {
+ Parse_Error (level, "if-less else");
+ return (COND_INVALID);
+ } else if (skipIfLevel == 0) {
+ value = !condStack[condTop];
+ } else {
+ return (COND_SKIP);
+ }
+ } else {
+ /*
+ * Not a valid conditional type. No error...
+ */
+ return (COND_INVALID);
+ }
+ } else {
+ if (isElse) {
+ if (condTop == MAXIF) {
+ Parse_Error (level, "if-less elif");
+ return (COND_INVALID);
+ } else if (skipIfLevel != 0) {
+ /*
+ * If skipping this conditional, just ignore the whole thing.
+ * If we don't, the user might be employing a variable that's
+ * undefined, for which there's an enclosing ifdef that
+ * we're skipping...
+ */
+ return(COND_SKIP);
+ }
+ } else if (skipLine) {
+ /*
+ * Don't even try to evaluate a conditional that's not an else if
+ * we're skipping things...
+ */
+ skipIfLevel += 1;
+ return(COND_SKIP);
+ }
+
+ /*
+ * Initialize file-global variables for parsing
+ */
+ condDefProc = ifp->defProc;
+ condInvert = ifp->doNot;
+
+ line += ifp->formlen;
+
+ while (*line == ' ' || *line == '\t') {
+ line++;
+ }
+
+ condExpr = line;
+ condPushBack = None;
+
+ switch (CondE(TRUE)) {
+ case True:
+ if (CondToken(TRUE) == EndOfFile) {
+ value = TRUE;
+ break;
+ }
+ goto err;
+ /*FALLTHRU*/
+ case False:
+ if (CondToken(TRUE) == EndOfFile) {
+ value = FALSE;
+ break;
+ }
+ /*FALLTHRU*/
+ case Err:
+ err:
+ Parse_Error (level, "Malformed conditional (%s)",
+ line);
+ return (COND_INVALID);
+ default:
+ break;
+ }
+ }
+ if (!isElse) {
+ condTop -= 1;
+ } else if ((skipIfLevel != 0) || condStack[condTop]) {
+ /*
+ * If this is an else-type conditional, it should only take effect
+ * if its corresponding if was evaluated and FALSE. If its if was
+ * TRUE or skipped, we return COND_SKIP (and start skipping in case
+ * we weren't already), leaving the stack unmolested so later elif's
+ * don't screw up...
+ */
+ skipLine = TRUE;
+ return (COND_SKIP);
+ }
+
+ if (condTop < 0) {
+ /*
+ * This is the one case where we can definitely proclaim a fatal
+ * error. If we don't, we're hosed.
+ */
+ Parse_Error (PARSE_FATAL, "Too many nested if's. %d max.", MAXIF);
+ return (COND_INVALID);
+ } else {
+ condStack[condTop] = value;
+ skipLine = !value;
+ return (value ? COND_PARSE : COND_SKIP);
+ }
+}
+
+/*-
+ *-----------------------------------------------------------------------
+ * Cond_End --
+ * Make sure everything's clean at the end of a makefile.
+ *
+ * Results:
+ * None.
+ *
+ * Side Effects:
+ * Parse_Error will be called if open conditionals are around.
+ *
+ *-----------------------------------------------------------------------
+ */
+void
+Cond_End()
+{
+ if (condTop != MAXIF) {
+ Parse_Error(PARSE_FATAL, "%d open conditional%s", MAXIF-condTop,
+ MAXIF-condTop == 1 ? "" : "s");
+ }
+ condTop = MAXIF;
+}
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