Module Name: src
Committed By: rillig
Date: Tue Sep 21 22:38:25 UTC 2021
Modified Files:
src/usr.bin/make: cond.c
src/usr.bin/make/unit-tests: cond-token-plain.exp cond-token-plain.mk
Log Message:
make: do not allow unquoted 'left == right' after modifier ':?'
Having a static variable for state that clearly belongs in the parser
looked suspicious, and indeed it was wrong.
When the distinction between .if conditions and expressions of the form
${condition:?:} was added in cond.c 1.68 from 2015-05-05, a new unit
test was added, but it didn't cover this edge case. At that time, the
state of the condition parser consisted of a few global variables
instead of a separate data type, as would have been appropriate for
parsing nested conditions.
To generate a diff of this commit:
cvs rdiff -u -r1.275 -r1.276 src/usr.bin/make/cond.c
cvs rdiff -u -r1.11 -r1.12 src/usr.bin/make/unit-tests/cond-token-plain.exp \
src/usr.bin/make/unit-tests/cond-token-plain.mk
Please note that diffs are not public domain; they are subject to the
copyright notices on the relevant files.
Modified files:
Index: src/usr.bin/make/cond.c
diff -u src/usr.bin/make/cond.c:1.275 src/usr.bin/make/cond.c:1.276
--- src/usr.bin/make/cond.c:1.275 Tue Sep 21 21:43:32 2021
+++ src/usr.bin/make/cond.c Tue Sep 21 22:38:25 2021
@@ -1,4 +1,4 @@
-/* $NetBSD: cond.c,v 1.275 2021/09/21 21:43:32 rillig Exp $ */
+/* $NetBSD: cond.c,v 1.276 2021/09/21 22:38:25 rillig Exp $ */
/*
* Copyright (c) 1988, 1989, 1990 The Regents of the University of California.
@@ -95,7 +95,7 @@
#include "dir.h"
/* "@(#)cond.c 8.2 (Berkeley) 1/2/94" */
-MAKE_RCSID("$NetBSD: cond.c,v 1.275 2021/09/21 21:43:32 rillig Exp $");
+MAKE_RCSID("$NetBSD: cond.c,v 1.276 2021/09/21 22:38:25 rillig Exp $");
/*
* The parsing of conditional expressions is based on this grammar:
@@ -154,6 +154,20 @@ typedef struct CondParser {
bool (*evalBare)(size_t, const char *);
bool negateEvalBare;
+ /*
+ * Whether the left-hand side of a comparison may NOT be an unquoted
+ * string. This is allowed for expressions of the form
+ * ${condition:?:}, see ApplyModifier_IfElse. Such a condition is
+ * expanded before it is evaluated, due to ease of implementation.
+ * This means that at the point where the condition is evaluated,
+ * make cannot know anymore whether the left-hand side had originally
+ * been a variable expression or a plain word.
+ *
+ * In all other contexts, the left-hand side must either be a
+ * variable expression, a quoted string or a number.
+ */
+ bool lhsStrict;
+
const char *p; /* The remaining condition to parse */
Token curr; /* Single push-back token used in parsing */
@@ -174,18 +188,6 @@ static unsigned int cond_min_depth = 0;
/* Names for ComparisonOp. */
static const char *opname[] = { "<", "<=", ">", ">=", "==", "!=" };
-/*
- * Indicate when we should be strict about lhs of comparisons.
- * In strict mode, the lhs must be a variable expression or a string literal
- * in quotes. In non-strict mode it may also be an unquoted string literal.
- *
- * True when CondEvalExpression is called from Cond_EvalLine (.if etc).
- * False when CondEvalExpression is called from ApplyModifier_IfElse
- * since lhs is already expanded, and at that point we cannot tell if
- * it was a variable reference or not.
- */
-static bool lhsStrict;
-
static bool
is_token(const char *str, const char *tok, size_t len)
{
@@ -682,7 +684,7 @@ CondParser_Comparison(CondParser *par, b
ComparisonOp op;
bool lhsQuoted, rhsQuoted;
- CondParser_Leaf(par, doEval, lhsStrict, &lhs, &lhsQuoted);
+ CondParser_Leaf(par, doEval, par->lhsStrict, &lhs, &lhsQuoted);
if (lhs.str == NULL)
goto done_lhs;
@@ -1063,13 +1065,12 @@ CondEvalExpression(const char *cond, boo
CondParser par;
CondEvalResult rval;
- lhsStrict = strictLHS;
-
cpp_skip_hspace(&cond);
par.plain = plain;
par.evalBare = evalBare;
par.negateEvalBare = negate;
+ par.lhsStrict = strictLHS;
par.p = cond;
par.curr = TOK_NONE;
par.printedError = false;
Index: src/usr.bin/make/unit-tests/cond-token-plain.exp
diff -u src/usr.bin/make/unit-tests/cond-token-plain.exp:1.11 src/usr.bin/make/unit-tests/cond-token-plain.exp:1.12
--- src/usr.bin/make/unit-tests/cond-token-plain.exp:1.11 Tue Sep 21 21:59:56 2021
+++ src/usr.bin/make/unit-tests/cond-token-plain.exp Tue Sep 21 22:38:25 2021
@@ -53,9 +53,9 @@ CondParser_Eval: left == right
make: "cond-token-plain.mk" line 191: Malformed conditional (left == right)
CondParser_Eval: ${0:?:} || left == right
CondParser_Eval: 0
-lhs = "left", rhs = "right", op = ==
+make: "cond-token-plain.mk" line 197: Malformed conditional (${0:?:} || left == right)
CondParser_Eval: left == right || ${0:?:}
-make: "cond-token-plain.mk" line 201: Malformed conditional (left == right || ${0:?:})
+make: "cond-token-plain.mk" line 202: Malformed conditional (left == right || ${0:?:})
make: Fatal errors encountered -- cannot continue
make: stopped in unit-tests
exit status 1
Index: src/usr.bin/make/unit-tests/cond-token-plain.mk
diff -u src/usr.bin/make/unit-tests/cond-token-plain.mk:1.11 src/usr.bin/make/unit-tests/cond-token-plain.mk:1.12
--- src/usr.bin/make/unit-tests/cond-token-plain.mk:1.11 Tue Sep 21 21:59:56 2021
+++ src/usr.bin/make/unit-tests/cond-token-plain.mk Tue Sep 21 22:38:25 2021
@@ -1,4 +1,4 @@
-# $NetBSD: cond-token-plain.mk,v 1.11 2021/09/21 21:59:56 rillig Exp $
+# $NetBSD: cond-token-plain.mk,v 1.12 2021/09/21 22:38:25 rillig Exp $
#
# Tests for plain tokens (that is, string literals without quotes)
# in .if conditions.
@@ -193,6 +193,7 @@ ${:U\\\\}= backslash
# Before cond.c 1.276 from 2021-09-21, a variable expression containing the
# modifier ':?:' allowed unquoted string literals for the rest of the
# condition. This was an unintended implementation mistake.
+# expect+1: Malformed conditional (${0:?:} || left == right)
.if ${0:?:} || left == right
.endif
# This affected only the comparisons after the expression, so the following
