1 files changed, 151 insertions, 0 deletions
diff --git a/trunk/eval_jump.c b/trunk/eval_jump.c
new file mode 100644
index 0000000000..f474844ba8
--- /dev/null
+++ b/trunk/eval_jump.c
@@ -0,0 +1,151 @@
+/* -*-c-*- */
+/*
+ * from eval.c
+ */
+
+#include "eval_intern.h"
+
+/* exit */
+
+void
+rb_call_end_proc(VALUE data)
+{
+    rb_proc_call(data, rb_ary_new());
+}
+
+/*
+ *  call-seq:
+ *     at_exit { block } -> proc
+ *
+ *  Converts _block_ to a +Proc+ object (and therefore
+ *  binds it at the point of call) and registers it for execution when
+ *  the program exits. If multiple handlers are registered, they are
+ *  executed in reverse order of registration.
+ *
+ *     def do_at_exit(str1)
+ *       at_exit { print str1 }
+ *     end
+ *     at_exit { puts "cruel world" }
+ *     do_at_exit("goodbye ")
+ *     exit
+ *
+ *  <em>produces:</em>
+ *
+ *     goodbye cruel world
+ */
+
+static VALUE
+rb_f_at_exit(void)
+{
+    VALUE proc;
+
+    if (!rb_block_given_p()) {
+	rb_raise(rb_eArgError, "called without a block");
+    }
+    proc = rb_block_proc();
+    rb_set_end_proc(rb_call_end_proc, proc);
+    return proc;
+}
+
+struct end_proc_data {
+    void (*func) ();
+    VALUE data;
+    int safe;
+    struct end_proc_data *next;
+};
+
+static struct end_proc_data *end_procs, *ephemeral_end_procs, *tmp_end_procs;
+
+void
+rb_set_end_proc(void (*func)(VALUE), VALUE data)
+{
+    struct end_proc_data *link = ALLOC(struct end_proc_data);
+    struct end_proc_data **list;
+    rb_thread_t *th = GET_THREAD();
+
+    if (th->top_wrapper) {
+	list = &ephemeral_end_procs;
+    }
+    else {
+	list = &end_procs;
+    }
+    link->next = *list;
+    link->func = func;
+    link->data = data;
+    link->safe = rb_safe_level();
+    *list = link;
+}
+
+void
+rb_mark_end_proc(void)
+{
+    struct end_proc_data *link;
+
+    link = end_procs;
+    while (link) {
+	rb_gc_mark(link->data);
+	link = link->next;
+    }
+    link = ephemeral_end_procs;
+    while (link) {
+	rb_gc_mark(link->data);
+	link = link->next;
+    }
+    link = tmp_end_procs;
+    while (link) {
+	rb_gc_mark(link->data);
+	link = link->next;
+    }
+}
+
+void
+rb_exec_end_proc(void)
+{
+    struct end_proc_data *link, *tmp;
+    int status;
+    volatile int safe = rb_safe_level();
+
+    while (ephemeral_end_procs) {
+	tmp_end_procs = link = ephemeral_end_procs;
+	ephemeral_end_procs = 0;
+	while (link) {
+	    PUSH_TAG();
+	    if ((status = EXEC_TAG()) == 0) {
+		rb_set_safe_level_force(link->safe);
+		(*link->func) (link->data);
+	    }
+	    POP_TAG();
+	    if (status) {
+		error_handle(status);
+	    }
+	    tmp = link;
+	    tmp_end_procs = link = link->next;
+	    xfree(tmp);
+	}
+    }
+    while (end_procs) {
+	tmp_end_procs = link = end_procs;
+	end_procs = 0;
+	while (link) {
+	    PUSH_TAG();
+	    if ((status = EXEC_TAG()) == 0) {
+		rb_set_safe_level_force(link->safe);
+		(*link->func) (link->data);
+	    }
+	    POP_TAG();
+	    if (status) {
+		error_handle(status);
+	    }
+	    tmp = link;
+	    tmp_end_procs = link = link->next;
+	    xfree(tmp);
+	}
+    }
+    rb_set_safe_level_force(safe);
+}
+
+void
+Init_jump(void)
+{
+    rb_define_global_function("at_exit", rb_f_at_exit, 0);
+}