Module Name: src
Committed By: rillig
Date: Sat May 25 15:37:17 UTC 2024
Modified Files:
src/usr.bin/make: compat.c
src/usr.bin/make/unit-tests: shell-csh.mk
Log Message:
make: minimize local variables around a vfork call
Passing all relevant values as arguments allows to remove the 'volatile'
qualifiers.
To generate a diff of this commit:
cvs rdiff -u -r1.255 -r1.256 src/usr.bin/make/compat.c
cvs rdiff -u -r1.8 -r1.9 src/usr.bin/make/unit-tests/shell-csh.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/compat.c
diff -u src/usr.bin/make/compat.c:1.255 src/usr.bin/make/compat.c:1.256
--- src/usr.bin/make/compat.c:1.255 Sat Apr 20 10:18:55 2024
+++ src/usr.bin/make/compat.c Sat May 25 15:37:17 2024
@@ -1,4 +1,4 @@
-/* $NetBSD: compat.c,v 1.255 2024/04/20 10:18:55 rillig Exp $ */
+/* $NetBSD: compat.c,v 1.256 2024/05/25 15:37:17 rillig Exp $ */
/*
* Copyright (c) 1988, 1989, 1990 The Regents of the University of California.
@@ -91,7 +91,7 @@
#include "pathnames.h"
/* "@(#)compat.c 8.2 (Berkeley) 3/19/94" */
-MAKE_RCSID("$NetBSD: compat.c,v 1.255 2024/04/20 10:18:55 rillig Exp $");
+MAKE_RCSID("$NetBSD: compat.c,v 1.256 2024/05/25 15:37:17 rillig Exp $");
static GNode *curTarg = NULL;
static pid_t compatChild;
@@ -200,6 +200,24 @@ UseShell(const char *cmd MAKE_ATTR_UNUSE
#endif
}
+static int
+Compat_Spawn(const char **av)
+{
+ int pid = vfork();
+ if (pid < 0)
+ Fatal("Could not fork");
+
+ if (pid == 0) {
+#ifdef USE_META
+ if (useMeta)
+ meta_compat_child();
+#endif
+ (void)execvp(av[0], (char *const *)UNCONST(av));
+ execDie("exec", av[0]);
+ }
+ return pid;
+}
+
/*
* Execute the next command for a target. If the command returns an error,
* the node's made field is set to ERROR and creation stops.
@@ -222,13 +240,12 @@ Compat_RunCommand(const char *cmdp, GNod
volatile bool errCheck; /* Check errors */
int reason; /* Reason for child's death */
int status; /* Description of child's death */
- pid_t cpid; /* Child actually found */
pid_t retstat; /* Result of wait */
- const char **volatile av; /* Argument vector for thing to exec */
+ const char **av; /* Arguments for the child process */
char **volatile mav; /* Copy of the argument vector for freeing */
bool useShell; /* True if command should be executed using a
* shell */
- const char *volatile cmd = cmdp;
+ const char *cmd = cmdp;
silent = (gn->type & OP_SILENT) != OP_NONE;
errCheck = !(gn->type & OP_IGNORE);
@@ -330,19 +347,7 @@ Compat_RunCommand(const char *cmdp, GNod
Var_ReexportVars(gn);
- compatChild = cpid = vfork();
- if (cpid < 0)
- Fatal("Could not fork");
-
- if (cpid == 0) {
-#ifdef USE_META
- if (useMeta)
- meta_compat_child();
-#endif
- (void)execvp(av[0], (char *const *)UNCONST(av));
- execDie("exec", av[0]);
- }
-
+ compatChild = Compat_Spawn(av);
free(mav);
free(bp);
@@ -352,11 +357,11 @@ Compat_RunCommand(const char *cmdp, GNod
#ifdef USE_META
if (useMeta)
- meta_compat_parent(cpid);
+ meta_compat_parent(compatChild);
#endif
/* The child is off and running. Now all we can do is wait... */
- while ((retstat = wait(&reason)) != cpid) {
+ while ((retstat = wait(&reason)) != compatChild) {
if (retstat > 0)
JobReapChild(retstat, reason, false); /* not ours? */
if (retstat == -1 && errno != EINTR)
Index: src/usr.bin/make/unit-tests/shell-csh.mk
diff -u src/usr.bin/make/unit-tests/shell-csh.mk:1.8 src/usr.bin/make/unit-tests/shell-csh.mk:1.9
--- src/usr.bin/make/unit-tests/shell-csh.mk:1.8 Sun Apr 4 09:58:51 2021
+++ src/usr.bin/make/unit-tests/shell-csh.mk Sat May 25 15:37:17 2024
@@ -1,4 +1,4 @@
-# $NetBSD: shell-csh.mk,v 1.8 2021/04/04 09:58:51 rillig Exp $
+# $NetBSD: shell-csh.mk,v 1.9 2024/05/25 15:37:17 rillig Exp $
#
# Tests for using a C shell for running the commands.
@@ -6,7 +6,7 @@ CSH!= which csh 2> /dev/null || true
# The shell path must be an absolute path.
# This is only obvious in parallel mode since in compat mode,
-# simple commands are executed via execve directly.
+# simple commands are executed via execvp directly.
.if ${CSH} != ""
.SHELL: name="csh" path="${CSH}"
.endif
