Module Name: src
Committed By: kre
Date: Mon Nov 26 13:47:39 UTC 2018
Modified Files:
src/bin/sh: eval.c
Log Message:
Make it be that an empty command is treated as a regular builtin
for the purposes of any redirects it might have -- ie: as posix
requires, make the redirects appear to have been executed in a subshell
environment, so if one fails, aside from a diagnositc msg, all the
running script sees is a command that failed ($? != 0), rather
that having the shell exit which used to happen (the empty command was
being treated as a special builtin).
Continue to treat the empty command as special for the purposes of
var assigns it might contain (those are not executed in a sub-shell
and persist) - an error there (eg: assigning to a readonly var) will
continue to cause the shell (non-interactive shell) to exit.
This makes the NetBSD shell behave like all other (reasonably modern)
shells - fix method (not the implementation, details differ) taken from
FreeBSD who fixed this back in early 2010. Problem pointed out
in (non-list) mail by Martijn Dekker.
To generate a diff of this commit:
cvs rdiff -u -r1.163 -r1.164 src/bin/sh/eval.c
Please note that diffs are not public domain; they are subject to the
copyright notices on the relevant files.
Modified files:
Index: src/bin/sh/eval.c
diff -u src/bin/sh/eval.c:1.163 src/bin/sh/eval.c:1.164
--- src/bin/sh/eval.c:1.163 Fri Nov 23 23:37:22 2018
+++ src/bin/sh/eval.c Mon Nov 26 13:47:39 2018
@@ -1,4 +1,4 @@
-/* $NetBSD: eval.c,v 1.163 2018/11/23 23:37:22 kre Exp $ */
+/* $NetBSD: eval.c,v 1.164 2018/11/26 13:47:39 kre Exp $ */
/*-
* Copyright (c) 1993
@@ -37,7 +37,7 @@
#if 0
static char sccsid[] = "@(#)eval.c 8.9 (Berkeley) 6/8/95";
#else
-__RCSID("$NetBSD: eval.c,v 1.163 2018/11/23 23:37:22 kre Exp $");
+__RCSID("$NetBSD: eval.c,v 1.164 2018/11/26 13:47:39 kre Exp $");
#endif
#endif /* not lint */
@@ -873,6 +873,7 @@ evalcommand(union node *cmd, int flgs, s
volatile int temp_path;
const int savefuncline = funclinebase;
const int savefuncabs = funclineabs;
+ volatile int cmd_flags = 0;
vforked = 0;
/* First expand the arguments. */
@@ -979,11 +980,16 @@ evalcommand(union node *cmd, int flgs, s
/* Now locate the command. */
if (argc == 0) {
- cmdentry.cmdtype = CMDSPLBLTIN;
+ /*
+ * the empty command begins as a normal builtin, and
+ * remains that way while redirects are processed, then
+ * will become special before we get to doing the
+ * var assigns.
+ */
+ cmdentry.cmdtype = CMDBUILTIN;
cmdentry.u.bltin = bltincmd;
} else {
static const char PATH[] = "PATH=";
- int cmd_flags = 0;
/*
* Modify the command lookup path, if a PATH= assignment
@@ -1224,9 +1230,11 @@ evalcommand(union node *cmd, int flgs, s
exitshell(exitstatus);
break;
- case CMDBUILTIN:
case CMDSPLBLTIN:
- VXTRACE(DBG_EVAL, ("builtin command%s: ",vforked?" VF":""), trargs(argv));
+ VTRACE(DBG_EVAL, ("special "));
+ case CMDBUILTIN:
+ VXTRACE(DBG_EVAL, ("builtin command [%d]%s: ", argc,
+ vforked ? " VF" : ""), trargs(argv));
mode = (cmdentry.u.bltin == execcmd) ? 0 : REDIR_PUSH;
if (flags == EV_BACKCMD) {
memout.nleft = 0;
@@ -1254,6 +1262,15 @@ evalcommand(union node *cmd, int flgs, s
}
redirect(cmd->ncmd.redirect, mode);
+ /*
+ * the empty command is regarded as a normal
+ * builtin for the purposes of redirects, but
+ * is a special builtin for var assigns.
+ * (unless we are the "command" command.)
+ */
+ if (argc == 0 && !(cmd_flags & DO_NOFUNC))
+ cmdentry.cmdtype = CMDSPLBLTIN;
+
/* exec is a special builtin, but needs this list... */
cmdenviron = varlist.list;
/* we must check 'readonly' flag for all builtins */
