[EVAL] Pass EV_TESTED into evalcmd

This patch fixes the case where the eval command is used with
set -e and as part of a construct that should not cause the
shell to abort, e.g., as part of the condition of an if statement.

This is achieved by propagating the EV_TESTED flag into the
evalstring function through evalcmd.  As this alters the prototype
of evalcmd it is now invoked explicitly by evalbltin.  The built-in
infrastructure has been changed to accomodate this special case.

In order to ensure that the EXIT trap is properly executed this
patch clears evalskip in exitshell.  This wasn't needed before
because of the broken way evalstring worked where it always clears
evalskip when called by minusc.

Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>

1 files changed, 15 insertions, 11 deletions

diff --git a/src/eval.c b/src/eval.c
index b90a354..66c2209 100644
--- a/src/eval.c
+++ b/src/eval.c
@@ -97,7 +97,7 @@ STATIC void evalcommand(union node *, int, struct backcmd *);
 #else
 STATIC void evalcommand(union node *, int);
 #endif
-STATIC int evalbltin(const struct builtincmd *, int, char **);
+STATIC int evalbltin(const struct builtincmd *, int, char **, int);
 STATIC int evalfun(struct funcnode *, int, char **, int);
 STATIC void prehash(union node *);
 STATIC int eprintlist(struct output *, struct strlist *, int);
@@ -129,8 +129,7 @@ RESET {
  * The eval commmand.
  */
 
-int
-evalcmd(int argc, char **argv)
+static int evalcmd(int argc, char **argv, int flags)
 {
         char *p;
         char *concat;
@@ -150,7 +149,7 @@ evalcmd(int argc, char **argv)
                         STPUTC('\0', concat);
                         p = grabstackstr(concat);
                 }
-                return evalstring(p, ~SKIPEVAL);
+                return evalstring(p, flags & EV_TESTED);
         }
         return 0;
 }
@@ -161,7 +160,7 @@ evalcmd(int argc, char **argv)
  */
 
 int
-evalstring(char *s, int mask)
+evalstring(char *s, int flags)
 {
 	union node *n;
 	struct stackmark smark;
@@ -172,7 +171,7 @@ evalstring(char *s, int mask)
 
 	status = 0;
 	while ((n = parsecmd(0)) != NEOF) {
-		evaltree(n, 0);
+		evaltree(n, flags);
 		status = exitstatus;
 		popstackmark(&smark);
 		if (evalskip)
@@ -180,7 +179,6 @@ evalstring(char *s, int mask)
 	}
 	popfile();
 
-	evalskip &= mask;
 	return status;
 }
 
@@ -861,7 +859,7 @@ bail:
 			}
 			listsetvar(list, i);
 		}
-		if (evalbltin(cmdentry.u.cmd, argc, argv)) {
+		if (evalbltin(cmdentry.u.cmd, argc, argv, flags)) {
 			int status;
 			int i;
 
@@ -899,10 +897,12 @@ out:
 }
 
 STATIC int
-evalbltin(const struct builtincmd *cmd, int argc, char **argv) {
+evalbltin(const struct builtincmd *cmd, int argc, char **argv, int flags)
+{
 	char *volatile savecmdname;
 	struct jmploc *volatile savehandler;
 	struct jmploc jmploc;
+	int status;
 	int i;
 
 	savecmdname = commandname;
@@ -913,10 +913,14 @@ evalbltin(const struct builtincmd *cmd, int argc, char **argv) {
 	commandname = argv[0];
 	argptr = argv + 1;
 	optptr = NULL;			/* initialize nextopt */
-	exitstatus = (*cmd->builtin)(argc, argv);
+	if (cmd == EVALCMD)
+		status = evalcmd(argc, argv, flags);
+	else
+		status = (*cmd->builtin)(argc, argv);
 	flushall();
+	status |= outerr(out1);
+	exitstatus = status;
 cmddone:
-	exitstatus |= outerr(out1);
 	freestdout();
 	commandname = savecmdname;
 	handler = savehandler;