From 8f5fe841a63fecdab4416578653549689f2c592f Mon Sep 17 00:00:00 2001
From: Peter Stephenson
Date: Mon, 17 Apr 2023 09:30:34 +0100
Subject: 51652: fix running of TRAPEXIT explicitly.
This is a special case where TRAPEXIT is unset within a TRAPEXIT
as it should never run in a nested context, so just save the
function structure temporarily on the heap.
---
Src/exec.c | 34 +++++++++++++++++++++++++++++++++-
1 file changed, 33 insertions(+), 1 deletion(-)
(limited to 'Src/exec.c')
diff --git a/Src/exec.c b/Src/exec.c
index 3b3d1235e..8f9d5a885 100644
--- a/Src/exec.c
+++ b/Src/exec.c
@@ -5779,12 +5779,25 @@ doshfunc(Shfunc shfunc, LinkList doshargs, int noreturnval)
char *name = shfunc->node.nam;
int flags = shfunc->node.flags;
char *fname = dupstring(name);
- Eprog prog;
+ Eprog prog, marked_prog;
static int oflags;
static int funcdepth;
Heap funcheap;
queue_signals(); /* Lots of memory and global state changes coming */
+ /*
+ * In case this is a special function such as a trap, mark it
+ * as in use right now, so it doesn't get freed early. The
+ * worst that can happen is this hangs around in memory a little
+ * longer than strictly needed.
+ *
+ * Classic example of this happening is running TRAPEXIT directly.
+ *
+ * Because the shell function's contents may change, we'll ensure
+ * we use a consistent structure for use / free.
+ */
+ marked_prog = shfunc->funcdef;
+ useeprog(marked_prog);
NEWHEAPS(funcheap) {
/*
@@ -5818,6 +5831,22 @@ doshfunc(Shfunc shfunc, LinkList doshargs, int noreturnval)
memcpy(funcsave->pipestats, pipestats, bytes);
}
+ if (!strcmp(fname, "TRAPEXIT")) {
+ /*
+ * If we are executing TRAPEXIT directly, starttrapscope()
+ * will pull the rug out from under us to ensure the
+ * exit trap isn't run inside the function. We just need
+ * the information locally here, so copy it on the heap.
+ *
+ * The funcdef is separately handled by reference counting.
+ */
+ Shfunc shcopy = (Shfunc)zhalloc(sizeof(struct shfunc));
+ memcpy(shcopy, shfunc, sizeof(struct shfunc));
+ shcopy->node.nam = dupstring(shfunc->node.nam);
+ shfunc = shcopy;
+ name = shfunc->node.nam;
+ }
+
starttrapscope();
startpatternscope();
@@ -5942,6 +5971,8 @@ doshfunc(Shfunc shfunc, LinkList doshargs, int noreturnval)
funcsave->fstack.filename = getshfuncfile(shfunc);
prog = shfunc->funcdef;
+ DPUTS1(!prog->nref, "function definition %s has zero reference count",
+ (fname && *fname) ? fname : "");
if (prog->flags & EF_RUN) {
Shfunc shf;
@@ -6046,6 +6077,7 @@ doshfunc(Shfunc shfunc, LinkList doshargs, int noreturnval)
}
} OLDHEAPS;
+ freeeprog(marked_prog);
unqueue_signals();
/*
--
cgit 1.4.1