[src/trunk]: src/usr.bin/make make(1): use better variable names in Var_Exists

[rillig <rillig%NetBSD.org@localhost>]

details:   https://anonhg.NetBSD.org/src/rev/ccc7aee1f66e
branches:  trunk
changeset: 936642:ccc7aee1f66e
user:      rillig <rillig%NetBSD.org@localhost>
date:      Sat Aug 01 07:29:04 2020 +0000

description:
make(1): use better variable names in Var_Exists

Calling strchr just to initialize a variable to NULL is not as
straight-forward as possible.

The unspecific variable name cp made it unnecessarily difficult to
understand its purpose.

diffstat:

 usr.bin/make/var.c |  19 +++++++++----------
 1 files changed, 9 insertions(+), 10 deletions(-)

diffs (46 lines):

diff -r bf8cf9ed2cb0 -r ccc7aee1f66e usr.bin/make/var.c
--- a/usr.bin/make/var.c        Sat Aug 01 07:14:05 2020 +0000
+++ b/usr.bin/make/var.c        Sat Aug 01 07:29:04 2020 +0000
@@ -1,4 +1,4 @@
-/*     $NetBSD: var.c,v 1.372 2020/08/01 07:14:04 rillig Exp $ */
+/*     $NetBSD: var.c,v 1.373 2020/08/01 07:29:04 rillig Exp $ */
 
 /*
  * Copyright (c) 1988, 1989, 1990, 1993
@@ -69,14 +69,14 @@
  */
 
 #ifndef MAKE_NATIVE
-static char rcsid[] = "$NetBSD: var.c,v 1.372 2020/08/01 07:14:04 rillig Exp $";
+static char rcsid[] = "$NetBSD: var.c,v 1.373 2020/08/01 07:29:04 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 1.372 2020/08/01 07:14:04 rillig Exp $");
+__RCSID("$NetBSD: var.c,v 1.373 2020/08/01 07:29:04 rillig Exp $");
 #endif
 #endif /* not lint */
 #endif
@@ -990,13 +990,12 @@
 Boolean
 Var_Exists(const char *name, GNode *ctxt)
 {
-    Var                  *v;
-    char          *cp;
-
-    if ((cp = strchr(name, '$')) != NULL)
-       cp = Var_Subst(name, ctxt, VARE_WANTRES);
-    v = VarFind(cp ? cp : name, ctxt, FIND_CMD | FIND_GLOBAL | FIND_ENV);
-    free(cp);
+    char *name_freeIt = NULL;
+    if (strchr(name, '$') != NULL)
+       name = name_freeIt = Var_Subst(name, ctxt, VARE_WANTRES);
+
+    Var *v = VarFind(name, ctxt, FIND_CMD | FIND_GLOBAL | FIND_ENV);
+    free(name_freeIt);
     if (v == NULL)
        return FALSE;