Module Name: src
Committed By: kre
Date: Mon May 9 21:03:10 UTC 2016
Modified Files:
src/bin/sh: eval.c eval.h main.c
Log Message:
PR bin/48875 - avoid holding (replaced) file descriptors open when running a
command in the current shell (so they can be restored for the next command)
in cases where it is obvious that there is not going to be a following
command to use them. This fixes the problem reported in the PR (though
there are still plenty of situations where a FD could be closed but isn't,
we do not do full fd flow eveluation to determine whether a fd will be
used or not).
This is the change that was just committed and then backed out again...
OK christos@
To generate a diff of this commit:
cvs rdiff -u -r1.124 -r1.125 src/bin/sh/eval.c
cvs rdiff -u -r1.18 -r1.19 src/bin/sh/eval.h
cvs rdiff -u -r1.66 -r1.67 src/bin/sh/main.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:1.124 src/bin/sh/eval.c:1.125
--- src/bin/sh/eval.c:1.124 Mon May 9 20:55:51 2016
+++ src/bin/sh/eval.c Mon May 9 21:03:10 2016
@@ -1,4 +1,4 @@
-/* $NetBSD: eval.c,v 1.124 2016/05/09 20:55:51 kre Exp $ */
+/* $NetBSD: eval.c,v 1.125 2016/05/09 21:03:10 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 1.124 2016/05/09 20:55:51 kre Exp $");
+__RCSID("$NetBSD: eval.c,v 1.125 2016/05/09 21:03:10 kre Exp $");
#endif
#endif /* not lint */
@@ -219,7 +219,7 @@ evalstring(char *s, int flag)
while ((n = parsecmd(0)) != NEOF) {
TRACE(("evalstring: "); showtree(n));
if (nflag == 0)
- evaltree(n, flag);
+ evaltree(n, flag | EV_MORE);
popstackmark(&smark);
}
popfile();
@@ -257,19 +257,20 @@ evaltree(union node *n, int flags)
#endif
switch (n->type) {
case NSEMI:
- evaltree(n->nbinary.ch1, flags & EV_TESTED);
+ evaltree(n->nbinary.ch1, (flags & EV_TESTED) |
+ (n->nbinary.ch2 ? EV_MORE : 0));
if (nflag || evalskip)
goto out;
evaltree(n->nbinary.ch2, flags);
break;
case NAND:
- evaltree(n->nbinary.ch1, EV_TESTED);
+ evaltree(n->nbinary.ch1, EV_TESTED | EV_MORE);
if (nflag || evalskip || exitstatus != 0)
goto out;
evaltree(n->nbinary.ch2, flags);
break;
case NOR:
- evaltree(n->nbinary.ch1, EV_TESTED);
+ evaltree(n->nbinary.ch1, EV_TESTED | EV_MORE);
if (nflag || evalskip || exitstatus == 0)
goto out;
evaltree(n->nbinary.ch2, flags);
@@ -281,14 +282,14 @@ evaltree(union node *n, int flags)
popredir();
break;
case NSUBSHELL:
- evalsubshell(n, flags);
+ evalsubshell(n, flags & ~EV_MORE);
do_etest = !(flags & EV_TESTED);
break;
case NBACKGND:
- evalsubshell(n, flags);
+ evalsubshell(n, flags & ~EV_MORE);
break;
case NIF: {
- evaltree(n->nif.test, EV_TESTED);
+ evaltree(n->nif.test, EV_TESTED | EV_MORE);
if (nflag || evalskip)
goto out;
if (exitstatus == 0)
@@ -314,7 +315,7 @@ evaltree(union node *n, int flags)
exitstatus = 0;
break;
case NNOT:
- evaltree(n->nnot.com, EV_TESTED);
+ evaltree(n->nnot.com, (flags & EV_MORE) | EV_TESTED);
exitstatus = !exitstatus;
break;
case NPIPE:
@@ -360,7 +361,7 @@ evalloop(union node *n, int flags)
TRACE(("evalloop done\n"));
for (;;) {
- evaltree(n->nbinary.ch1, EV_TESTED);
+ evaltree(n->nbinary.ch1, EV_TESTED | EV_MORE);
if (nflag)
break;
if (evalskip) {
@@ -379,7 +380,7 @@ skipping: if (evalskip == SKIPCONT &&
if (exitstatus == 0)
break;
}
- evaltree(n->nbinary.ch2, flags & EV_TESTED);
+ evaltree(n->nbinary.ch2, flags & (EV_TESTED | EV_MORE));
status = exitstatus;
if (evalskip)
goto skipping;
@@ -413,7 +414,7 @@ evalfor(union node *n, int flags)
loopnest++;
for (sp = arglist.list ; sp ; sp = sp->next) {
setvar(n->nfor.var, sp->text, 0);
- evaltree(n->nfor.body, flags & EV_TESTED);
+ evaltree(n->nfor.body, flags & (EV_TESTED | EV_MORE));
status = exitstatus;
if (nflag)
break;
@@ -881,6 +882,8 @@ evalcommand(union node *cmd, int flgs, s
INTOFF;
jp = makejob(cmd, 1);
mode = cmd->ncmd.backgnd;
+ if (mode)
+ flags &= ~EV_MORE;
if (flags & EV_BACKCMD) {
mode = FORK_NOJOB;
if (sh_pipe(pip) < 0)
@@ -967,7 +970,7 @@ normal_fork:
#ifdef DEBUG
trputs("Shell function: "); trargs(argv);
#endif
- redirect(cmd->ncmd.redirect, REDIR_PUSH);
+ redirect(cmd->ncmd.redirect, flags & EV_MORE ? REDIR_PUSH : 0);
saveparam = shellparam;
shellparam.malloc = 0;
shellparam.reset = 1;
@@ -1005,7 +1008,8 @@ normal_fork:
freeparam(&shellparam);
shellparam = saveparam;
handler = savehandler;
- popredir();
+ if (flags & EV_MORE)
+ popredir();
INTON;
if (evalskip == SKIPFUNC) {
evalskip = SKIPNONE;
Index: src/bin/sh/eval.h
diff -u src/bin/sh/eval.h:1.18 src/bin/sh/eval.h:1.19
--- src/bin/sh/eval.h:1.18 Mon May 9 20:55:51 2016
+++ src/bin/sh/eval.h Mon May 9 21:03:10 2016
@@ -1,4 +1,4 @@
-/* $NetBSD: eval.h,v 1.18 2016/05/09 20:55:51 kre Exp $ */
+/* $NetBSD: eval.h,v 1.19 2016/05/09 21:03:10 kre Exp $ */
/*-
* Copyright (c) 1991, 1993
@@ -71,3 +71,9 @@ void stop_skipping(void); /* reset inter
* Only for use by reset() in init.c!
*/
void reset_eval(void);
+
+/* flags in argument to evaltree */
+#define EV_EXIT 0x01 /* exit after evaluating tree */
+#define EV_TESTED 0x02 /* exit status is checked; ignore -e flag */
+#define EV_BACKCMD 0x04 /* command executing within back quotes */
+#define EV_MORE 0x08 /* more commands in this sub-shell */
Index: src/bin/sh/main.c
diff -u src/bin/sh/main.c:1.66 src/bin/sh/main.c:1.67
--- src/bin/sh/main.c:1.66 Mon May 9 20:55:51 2016
+++ src/bin/sh/main.c Mon May 9 21:03:10 2016
@@ -1,4 +1,4 @@
-/* $NetBSD: main.c,v 1.66 2016/05/09 20:55:51 kre Exp $ */
+/* $NetBSD: main.c,v 1.67 2016/05/09 21:03:10 kre Exp $ */
/*-
* Copyright (c) 1991, 1993
@@ -42,7 +42,7 @@ __COPYRIGHT("@(#) Copyright (c) 1991, 19
#if 0
static char sccsid[] = "@(#)main.c 8.7 (Berkeley) 7/19/95";
#else
-__RCSID("$NetBSD: main.c,v 1.66 2016/05/09 20:55:51 kre Exp $");
+__RCSID("$NetBSD: main.c,v 1.67 2016/05/09 21:03:10 kre Exp $");
#endif
#endif /* not lint */
@@ -282,7 +282,7 @@ cmdloop(int top)
} else if (n != NULL && nflag == 0) {
job_warning = (job_warning == 2) ? 1 : 0;
numeof = 0;
- evaltree(n, 0);
+ evaltree(n, EV_MORE);
}
popstackmark(&smark);
setstackmark(&smark);
