redir: Clear saved redirections in subshell

When we enter a subshell we need to drop the saved redirections
as otherwise a subsequent unwindredir could produce incorrect
results.

This patch does this by simply clearing redirlist.  While we
could actually free the memory underneath for subshells it isn't
really worth the trouble for now.

In order to ensure that this is done in every place where we enter
a subshell, this patch adds a new mkinit hook called forkreset.
The calls closescript, clear_traps and reset_handler are also added
to the forkreset hook.

This fixes a bug where the first two functions weren't called
if we enter a subshell without forking.

Reported-by: Harald van Dijk <harald@gigawatt.nl>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>

1 files changed, 6 insertions, 3 deletions

diff --git a/src/main.c b/src/main.c
index b2712cb..36431fc 100644
--- a/src/main.c
+++ b/src/main.c
@@ -71,7 +71,7 @@ int *dash_errno;
 short profile_buf[16384];
 extern int etext();
 #endif
-static struct jmploc main_handler;
+MKINIT struct jmploc main_handler;
 
 STATIC void read_profile(const char *);
 STATIC char *find_dot_file(char *);
@@ -354,7 +354,10 @@ exitcmd(int argc, char **argv)
 	/* NOTREACHED */
 }
 
-void reset_handler(void)
-{
+#ifdef mkinit
+INCLUDE "error.h"
+
+FORKRESET {
 	handler = &main_handler;
 }
+#endif