* cont.c, vm_core.h, eval.c: because rb_protect must not be jumped by

callcc, revert r26407.  And rename trap_tag to protect_tag and
  change exception message (across trap -> across stack rewinding
  barrier).

git-svn-id: svn+ssh://ci.ruby-lang.org/ruby/trunk@26415 b2dd03c8-39d4-4d8f-98ff-823fe69b080e

ChangeLog

@@ -1,3 +1,10 @@
+Tue Jan 26 03:16:45 2010  Yusuke Endoh  <mame@tsg.ne.jp>
+
+	* cont.c, vm_core.h, eval.c: because rb_protect must not be jumped by
+	  callcc, revert r26407.  And rename trap_tag to protect_tag and
+	  change exception message (across trap -> across stack rewinding
+	  barrier).
+
 Mon Jan 25 23:08:10 2010  NAKAMURA Usaku  <usa@ruby-lang.org>
 
 	* thread.c (do_select): wrong conditions.  [ruby-core:27753]

cont.c

@@ -388,6 +388,7 @@ cont_restore_1(rb_context_t *cont)
     th->state = sth->state;
     th->status = sth->status;
     th->tag = sth->tag;
+    th->protect_tag = sth->protect_tag;
     th->errinfo = sth->errinfo;
     th->first_proc = sth->first_proc;
 
@@ -620,6 +621,9 @@ rb_cont_call(int argc, VALUE *argv, VALUE contval)
     if (cont->saved_thread.self != th->self) {
 	rb_raise(rb_eRuntimeError, "continuation called across threads");
     }
+    if (cont->saved_thread.protect_tag != th->protect_tag) {
+	rb_raise(rb_eRuntimeError, "continuation called across stack rewinding barrier");
+    }
     if (cont->saved_thread.fiber) {
 	rb_fiber_t *fcont;
 	GetFiberPtr(cont->saved_thread.fiber, fcont);
@@ -936,6 +940,9 @@ fiber_switch(VALUE fibval, int argc, VALUE *argv, int is_resume)
     if (cont->saved_thread.self != th->self) {
 	rb_raise(rb_eFiberError, "fiber called across threads");
     }
+    else if (cont->saved_thread.protect_tag != th->protect_tag) {
+	rb_raise(rb_eFiberError, "fiber called across stack rewinding barrier");
+    }
     else if (fib->status == TERMINATED) {
 	value = rb_exc_new2(rb_eFiberError, "dead fiber called");
 	if (th->fiber != fibval) rb_exc_raise(value);

eval.c

@@ -690,14 +690,19 @@ rb_protect(VALUE (* proc) (VALUE), VALUE data, int * state)
     int status;
     rb_thread_t *th = GET_THREAD();
     rb_control_frame_t *cfp = th->cfp;
+    struct rb_vm_protect_tag protect_tag;
     rb_jmpbuf_t org_jmpbuf;
 
+    protect_tag.prev = th->protect_tag;
+
     PUSH_TAG();
+    th->protect_tag = &protect_tag;
     MEMCPY(&org_jmpbuf, &(th)->root_jmpbuf, rb_jmpbuf_t, 1);
     if ((status = EXEC_TAG()) == 0) {
 	SAVE_ROOT_JMPBUF(th, result = (*proc) (data));
     }
     MEMCPY(&(th)->root_jmpbuf, &org_jmpbuf, rb_jmpbuf_t, 1);
+    th->protect_tag = protect_tag.prev;
     POP_TAG();
 
     if (state) {

vm_core.h

@@ -347,6 +347,10 @@ struct rb_vm_tag {
     struct rb_vm_tag *prev;
 };
 
+struct rb_vm_protect_tag {
+    struct rb_vm_protect_tag *prev;
+};
+
 #define RUBY_VM_VALUE_CACHE_SIZE 0x1000
 #define USE_VALUE_CACHE 0
 
@@ -410,6 +414,7 @@ typedef struct rb_thread_struct
     int transition_for_lock;
 
     struct rb_vm_tag *tag;
+    struct rb_vm_protect_tag *protect_tag;
 
     int parse_in_eval;
     int mild_compile_error;