Module Name: src
Committed By: rillig
Date: Sat Aug 22 20:31:50 UTC 2020
Modified Files:
src/usr.bin/make: var.c
src/usr.bin/make/unit-tests: varname-empty.exp varname-empty.mk
Log Message:
make(1): prevent assignment to the variable with the empty name
To generate a diff of this commit:
cvs rdiff -u -r1.457 -r1.458 src/usr.bin/make/var.c
cvs rdiff -u -r1.1 -r1.2 src/usr.bin/make/unit-tests/varname-empty.exp \
src/usr.bin/make/unit-tests/varname-empty.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/var.c
diff -u src/usr.bin/make/var.c:1.457 src/usr.bin/make/var.c:1.458
--- src/usr.bin/make/var.c:1.457 Sat Aug 22 19:30:58 2020
+++ src/usr.bin/make/var.c Sat Aug 22 20:31:50 2020
@@ -1,4 +1,4 @@
-/* $NetBSD: var.c,v 1.457 2020/08/22 19:30:58 sjg Exp $ */
+/* $NetBSD: var.c,v 1.458 2020/08/22 20:31:50 rillig Exp $ */
/*
* Copyright (c) 1988, 1989, 1990, 1993
@@ -69,14 +69,14 @@
*/
#ifndef MAKE_NATIVE
-static char rcsid[] = "$NetBSD: var.c,v 1.457 2020/08/22 19:30:58 sjg Exp $";
+static char rcsid[] = "$NetBSD: var.c,v 1.458 2020/08/22 20:31:50 rillig Exp $";
#else
#include <sys/cdefs.h>
#ifndef lint
#if 0
static char sccsid[] = "@(#)var.c 8.3 (Berkeley) 3/19/94";
#else
-__RCSID("$NetBSD: var.c,v 1.457 2020/08/22 19:30:58 sjg Exp $");
+__RCSID("$NetBSD: var.c,v 1.458 2020/08/22 20:31:50 rillig Exp $");
#endif
#endif /* not lint */
#endif
@@ -778,6 +778,7 @@ void
Var_Set_with_flags(const char *name, const char *val, GNode *ctxt,
VarSet_Flags flags)
{
+ const char *unexpanded_name = name;
char *name_freeIt = NULL;
Var *v;
@@ -786,16 +787,15 @@ Var_Set_with_flags(const char *name, con
* here will override anything in a lower context, so there's not much
* point in searching them all just to save a bit of memory...
*/
- if (strchr(name, '$') != NULL) {
- const char *unexpanded_name = name;
+ if (strchr(name, '$') != NULL)
name = name_freeIt = Var_Subst(name, ctxt, VARE_WANTRES);
- if (name[0] == '\0') {
- VAR_DEBUG("Var_Set(\"%s\", \"%s\", ...) "
- "name expands to empty string - ignored\n",
- unexpanded_name, val);
- free(name_freeIt);
- return;
- }
+
+ if (name[0] == '\0') {
+ VAR_DEBUG("Var_Set(\"%s\", \"%s\", ...) "
+ "name expands to empty string - ignored\n",
+ unexpanded_name, val);
+ free(name_freeIt);
+ return;
}
if (ctxt == VAR_GLOBAL) {
Index: src/usr.bin/make/unit-tests/varname-empty.exp
diff -u src/usr.bin/make/unit-tests/varname-empty.exp:1.1 src/usr.bin/make/unit-tests/varname-empty.exp:1.2
--- src/usr.bin/make/unit-tests/varname-empty.exp:1.1 Sat Aug 22 20:23:14 2020
+++ src/usr.bin/make/unit-tests/varname-empty.exp Sat Aug 22 20:31:50 2020
@@ -1,3 +1,3 @@
-value
-value value value
+fallback
+1 2 3
exit status 0
Index: src/usr.bin/make/unit-tests/varname-empty.mk
diff -u src/usr.bin/make/unit-tests/varname-empty.mk:1.1 src/usr.bin/make/unit-tests/varname-empty.mk:1.2
--- src/usr.bin/make/unit-tests/varname-empty.mk:1.1 Sat Aug 22 20:23:14 2020
+++ src/usr.bin/make/unit-tests/varname-empty.mk Sat Aug 22 20:31:50 2020
@@ -1,4 +1,4 @@
-# $NetBSD: varname-empty.mk,v 1.1 2020/08/22 20:23:14 rillig Exp $
+# $NetBSD: varname-empty.mk,v 1.2 2020/08/22 20:31:50 rillig Exp $
#
# Tests for the special variable with the empty name.
#
@@ -6,7 +6,8 @@
# This is because it is heavily used in the .for loop expansion,
# as well as to generate arbitrary strings, as in ${:Ufallback}.
-# Oops.
+# Until 2020-08-22 it was possible to assign a value to the variable with
+# the empty name, leading to all kinds of unexpected effects.
!= echo 'value'
# The .for loop expands the expression ${i} to ${:U1}, ${:U2} and so on.
