/* Evaluator for GNU Emacs Lisp interpreter.
- Copyright (C) 1985-1987, 1993-1995, 1999-2013 Free Software
- Foundation, Inc.
+
+Copyright (C) 1985-1987, 1993-1995, 1999-2014 Free Software Foundation,
+Inc.
This file is part of GNU Emacs.
#include "commands.h"
#include "keyboard.h"
#include "dispextern.h"
-#include "frame.h" /* For XFRAME. */
-
-#if HAVE_X_WINDOWS
-#include "xterm.h"
-#endif
-
-#if !BYTE_MARK_STACK
-static
-#endif
-struct catchtag *catchlist;
-/* Chain of condition handlers currently in effect.
- The elements of this chain are contained in the stack frames
- of Fcondition_case and internal_condition_case.
- When an error is signaled (by calling Fsignal, below),
- this chain is searched for an element that applies. */
+/* Chain of condition and catch handlers currently in effect. */
-#if !BYTE_MARK_STACK
-static
-#endif
struct handler *handlerlist;
#ifdef DEBUG_GCPRO
Lisp_Object Vautoload_queue;
-/* Current number of specbindings allocated in specpdl. */
+/* Current number of specbindings allocated in specpdl, not counting
+ the dummy entry specpdl[-1]. */
ptrdiff_t specpdl_size;
-/* Pointer to beginning of specpdl. */
+/* Pointer to beginning of specpdl. A dummy entry specpdl[-1] exists
+ only so that its address can be taken. */
-struct specbinding *specpdl;
+union specbinding *specpdl;
/* Pointer to first unused element in specpdl. */
-struct specbinding *specpdl_ptr;
+union specbinding *specpdl_ptr;
/* Depth in Lisp evaluations and function calls. */
-static EMACS_INT lisp_eval_depth;
+EMACS_INT lisp_eval_depth;
/* The value of num_nonmacro_input_events as of the last time we
started to enter the debugger. If we decide to enter the debugger
frame is half-initialized. */
Lisp_Object inhibit_lisp_code;
+/* These would ordinarily be static, but they need to be visible to GDB. */
+bool backtrace_p (union specbinding *) EXTERNALLY_VISIBLE;
+Lisp_Object *backtrace_args (union specbinding *) EXTERNALLY_VISIBLE;
+Lisp_Object backtrace_function (union specbinding *) EXTERNALLY_VISIBLE;
+union specbinding *backtrace_next (union specbinding *) EXTERNALLY_VISIBLE;
+union specbinding *backtrace_top (void) EXTERNALLY_VISIBLE;
+
static Lisp_Object funcall_lambda (Lisp_Object, ptrdiff_t, Lisp_Object *);
static Lisp_Object apply_lambda (Lisp_Object fun, Lisp_Object args);
+static Lisp_Object
+specpdl_symbol (union specbinding *pdl)
+{
+ eassert (pdl->kind >= SPECPDL_LET);
+ return pdl->let.symbol;
+}
+
+static Lisp_Object
+specpdl_old_value (union specbinding *pdl)
+{
+ eassert (pdl->kind >= SPECPDL_LET);
+ return pdl->let.old_value;
+}
+
+static void
+set_specpdl_old_value (union specbinding *pdl, Lisp_Object val)
+{
+ eassert (pdl->kind >= SPECPDL_LET);
+ pdl->let.old_value = val;
+}
+
+static Lisp_Object
+specpdl_where (union specbinding *pdl)
+{
+ eassert (pdl->kind > SPECPDL_LET);
+ return pdl->let.where;
+}
+
+static Lisp_Object
+specpdl_arg (union specbinding *pdl)
+{
+ eassert (pdl->kind == SPECPDL_UNWIND);
+ return pdl->unwind.arg;
+}
+
+Lisp_Object
+backtrace_function (union specbinding *pdl)
+{
+ eassert (pdl->kind == SPECPDL_BACKTRACE);
+ return pdl->bt.function;
+}
+
+static ptrdiff_t
+backtrace_nargs (union specbinding *pdl)
+{
+ eassert (pdl->kind == SPECPDL_BACKTRACE);
+ return pdl->bt.nargs;
+}
+
+Lisp_Object *
+backtrace_args (union specbinding *pdl)
+{
+ eassert (pdl->kind == SPECPDL_BACKTRACE);
+ return pdl->bt.args;
+}
+
+static bool
+backtrace_debug_on_exit (union specbinding *pdl)
+{
+ eassert (pdl->kind == SPECPDL_BACKTRACE);
+ return pdl->bt.debug_on_exit;
+}
+
/* Functions to modify slots of backtrace records. */
static void
-set_backtrace_args (struct specbinding *pdl, Lisp_Object *args)
-{ eassert (pdl->kind == SPECPDL_BACKTRACE); pdl->v.bt.args = args; }
+set_backtrace_args (union specbinding *pdl, Lisp_Object *args)
+{
+ eassert (pdl->kind == SPECPDL_BACKTRACE);
+ pdl->bt.args = args;
+}
static void
-set_backtrace_nargs (struct specbinding *pdl, ptrdiff_t n)
-{ eassert (pdl->kind == SPECPDL_BACKTRACE); pdl->v.bt.nargs = n; }
+set_backtrace_nargs (union specbinding *pdl, ptrdiff_t n)
+{
+ eassert (pdl->kind == SPECPDL_BACKTRACE);
+ pdl->bt.nargs = n;
+}
static void
-set_backtrace_debug_on_exit (struct specbinding *pdl, bool doe)
-{ eassert (pdl->kind == SPECPDL_BACKTRACE); pdl->v.bt.debug_on_exit = doe; }
+set_backtrace_debug_on_exit (union specbinding *pdl, bool doe)
+{
+ eassert (pdl->kind == SPECPDL_BACKTRACE);
+ pdl->bt.debug_on_exit = doe;
+}
/* Helper functions to scan the backtrace. */
-bool backtrace_p (struct specbinding *) EXTERNALLY_VISIBLE;
-struct specbinding *backtrace_top (void) EXTERNALLY_VISIBLE;
-struct specbinding *backtrace_next (struct specbinding *pdl) EXTERNALLY_VISIBLE;
-
-bool backtrace_p (struct specbinding *pdl)
+bool
+backtrace_p (union specbinding *pdl)
{ return pdl >= specpdl; }
-struct specbinding *
+union specbinding *
backtrace_top (void)
{
- struct specbinding *pdl = specpdl_ptr - 1;
+ union specbinding *pdl = specpdl_ptr - 1;
while (backtrace_p (pdl) && pdl->kind != SPECPDL_BACKTRACE)
pdl--;
return pdl;
}
-struct specbinding *
-backtrace_next (struct specbinding *pdl)
+union specbinding *
+backtrace_next (union specbinding *pdl)
{
pdl--;
while (backtrace_p (pdl) && pdl->kind != SPECPDL_BACKTRACE)
init_eval_once (void)
{
enum { size = 50 };
- specpdl = xmalloc (size * sizeof *specpdl);
+ union specbinding *pdlvec = xmalloc ((size + 1) * sizeof *specpdl);
specpdl_size = size;
- specpdl_ptr = specpdl;
+ specpdl = specpdl_ptr = pdlvec + 1;
/* Don't forget to update docs (lispref node "Local Variables"). */
max_specpdl_size = 1300; /* 1000 is not enough for CEDET's c-by.el. */
max_lisp_eval_depth = 600;
Vrun_hooks = Qnil;
}
+static struct handler handlerlist_sentinel;
+
void
init_eval (void)
{
specpdl_ptr = specpdl;
- catchlist = 0;
- handlerlist = 0;
+ { /* Put a dummy catcher at top-level so that handlerlist is never NULL.
+ This is important since handlerlist->nextfree holds the freelist
+ which would otherwise leak every time we unwind back to top-level. */
+ struct handler *c;
+ handlerlist = handlerlist_sentinel.nextfree = &handlerlist_sentinel;
+ PUSH_HANDLER (c, Qunbound, CATCHER);
+ eassert (c == &handlerlist_sentinel);
+ handlerlist_sentinel.nextfree = NULL;
+ handlerlist_sentinel.next = NULL;
+ }
Vquit_flag = Qnil;
debug_on_next_call = 0;
lisp_eval_depth = 0;
/* Unwind-protect function used by call_debugger. */
-static Lisp_Object
+static void
restore_stack_limits (Lisp_Object data)
{
max_specpdl_size = XINT (XCAR (data));
max_lisp_eval_depth = XINT (XCDR (data));
- return Qnil;
}
+static void grow_specpdl (void);
+
/* Call the Lisp debugger, giving it argument ARG. */
Lisp_Object
bool debug_while_redisplaying;
ptrdiff_t count = SPECPDL_INDEX ();
Lisp_Object val;
- EMACS_INT old_max = max_specpdl_size;
-
- /* Temporarily bump up the stack limits,
- so the debugger won't run out of stack. */
-
- max_specpdl_size += 1;
- record_unwind_protect (restore_stack_limits,
- Fcons (make_number (old_max),
- make_number (max_lisp_eval_depth)));
- max_specpdl_size = old_max;
+ EMACS_INT old_depth = max_lisp_eval_depth;
+ /* Do not allow max_specpdl_size less than actual depth (Bug#16603). */
+ EMACS_INT old_max = max (max_specpdl_size, count);
if (lisp_eval_depth + 40 > max_lisp_eval_depth)
max_lisp_eval_depth = lisp_eval_depth + 40;
- if (max_specpdl_size - 100 < SPECPDL_INDEX ())
- max_specpdl_size = SPECPDL_INDEX () + 100;
+ /* While debugging Bug#16603, previous value of 100 was found
+ too small to avoid specpdl overflow in the debugger itself. */
+ if (max_specpdl_size - 200 < count)
+ max_specpdl_size = count + 200;
+
+ if (old_max == count)
+ {
+ /* We can enter the debugger due to specpdl overflow (Bug#16603). */
+ specpdl_ptr--;
+ grow_specpdl ();
+ }
+
+ /* Restore limits after leaving the debugger. */
+ record_unwind_protect (restore_stack_limits,
+ Fcons (make_number (old_max),
+ make_number (old_depth)));
#ifdef HAVE_WINDOW_SYSTEM
if (display_hourglass_p)
{
debug_on_next_call = 0;
set_backtrace_debug_on_exit (specpdl_ptr - 1, true);
- call_debugger (Fcons (code, Qnil));
+ call_debugger (list1 (code));
}
\f
/* NOTE!!! Every function that can call EVAL must protect its args
usage: (if COND THEN ELSE...) */)
(Lisp_Object args)
{
- register Lisp_Object cond;
+ Lisp_Object cond;
struct gcpro gcpro1;
GCPRO1 (args);
- cond = eval_sub (Fcar (args));
+ cond = eval_sub (XCAR (args));
UNGCPRO;
if (!NILP (cond))
- return eval_sub (Fcar (Fcdr (args)));
- return Fprogn (Fcdr (Fcdr (args)));
+ return eval_sub (Fcar (XCDR (args)));
+ return Fprogn (XCDR (XCDR (args)));
}
DEFUN ("cond", Fcond, Scond, 0, UNEVALLED, 0,
and, if the value is non-nil, this clause succeeds:
then the expressions in BODY are evaluated and the last one's
value is the value of the cond-form.
+If a clause has one element, as in (CONDITION), then the cond-form
+returns CONDITION's value, if that is non-nil.
If no clause succeeds, cond returns nil.
-If a clause has one element, as in (CONDITION),
-CONDITION's value if non-nil is returned from the cond-form.
usage: (cond CLAUSES...) */)
(Lisp_Object args)
{
- register Lisp_Object clause, val;
+ Lisp_Object val = args;
struct gcpro gcpro1;
- val = Qnil;
GCPRO1 (args);
- while (!NILP (args))
+ while (CONSP (args))
{
- clause = Fcar (args);
+ Lisp_Object clause = XCAR (args);
val = eval_sub (Fcar (clause));
if (!NILP (val))
{
- if (!EQ (XCDR (clause), Qnil))
+ if (!NILP (XCDR (clause)))
val = Fprogn (XCDR (clause));
break;
}
DEFUN ("progn", Fprogn, Sprogn, 0, UNEVALLED, 0,
doc: /* Eval BODY forms sequentially and return value of last one.
usage: (progn BODY...) */)
- (Lisp_Object args)
+ (Lisp_Object body)
{
- register Lisp_Object val = Qnil;
+ Lisp_Object val = Qnil;
struct gcpro gcpro1;
- GCPRO1 (args);
+ GCPRO1 (body);
- while (CONSP (args))
+ while (CONSP (body))
{
- val = eval_sub (XCAR (args));
- args = XCDR (args);
+ val = eval_sub (XCAR (body));
+ body = XCDR (body);
}
UNGCPRO;
return val;
}
+/* Evaluate BODY sequentially, discarding its value. Suitable for
+ record_unwind_protect. */
+
+void
+unwind_body (Lisp_Object body)
+{
+ Fprogn (body);
+}
+
DEFUN ("prog1", Fprog1, Sprog1, 1, UNEVALLED, 0,
doc: /* Eval FIRST and BODY sequentially; return value from FIRST.
The value of FIRST is saved during the evaluation of the remaining args,
(Lisp_Object args)
{
Lisp_Object val;
- register Lisp_Object args_left;
+ Lisp_Object args_left;
struct gcpro gcpro1, gcpro2;
args_left = args;
- val = Qnil;
+ val = args;
GCPRO2 (args, val);
val = eval_sub (XCAR (args_left));
usage: (setq [SYM VAL]...) */)
(Lisp_Object args)
{
- register Lisp_Object args_left;
- register Lisp_Object val, sym, lex_binding;
- struct gcpro gcpro1;
-
- if (NILP (args))
- return Qnil;
+ Lisp_Object val, sym, lex_binding;
- args_left = args;
- GCPRO1 (args);
-
- do
+ val = args;
+ if (CONSP (args))
{
- val = eval_sub (Fcar (Fcdr (args_left)));
- sym = Fcar (args_left);
+ Lisp_Object args_left = args;
+ struct gcpro gcpro1;
+ GCPRO1 (args);
- /* Like for eval_sub, we do not check declared_special here since
- it's been done when let-binding. */
- if (!NILP (Vinternal_interpreter_environment) /* Mere optimization! */
- && SYMBOLP (sym)
- && !NILP (lex_binding
- = Fassq (sym, Vinternal_interpreter_environment)))
- XSETCDR (lex_binding, val); /* SYM is lexically bound. */
- else
- Fset (sym, val); /* SYM is dynamically bound. */
+ do
+ {
+ val = eval_sub (Fcar (XCDR (args_left)));
+ sym = XCAR (args_left);
+
+ /* Like for eval_sub, we do not check declared_special here since
+ it's been done when let-binding. */
+ if (!NILP (Vinternal_interpreter_environment) /* Mere optimization! */
+ && SYMBOLP (sym)
+ && !NILP (lex_binding
+ = Fassq (sym, Vinternal_interpreter_environment)))
+ XSETCDR (lex_binding, val); /* SYM is lexically bound. */
+ else
+ Fset (sym, val); /* SYM is dynamically bound. */
+
+ args_left = Fcdr (XCDR (args_left));
+ }
+ while (CONSP (args_left));
- args_left = Fcdr (Fcdr (args_left));
+ UNGCPRO;
}
- while (!NILP (args_left));
- UNGCPRO;
return val;
}
usage: (quote ARG) */)
(Lisp_Object args)
{
- if (!NILP (Fcdr (args)))
+ if (CONSP (XCDR (args)))
xsignal2 (Qwrong_number_of_arguments, Qquote, Flength (args));
- return Fcar (args);
+ return XCAR (args);
}
DEFUN ("function", Ffunction, Sfunction, 1, UNEVALLED, 0,
{
Lisp_Object quoted = XCAR (args);
- if (!NILP (Fcdr (args)))
+ if (CONSP (XCDR (args)))
xsignal2 (Qwrong_number_of_arguments, Qfunction, Flength (args));
if (!NILP (Vinternal_interpreter_environment)
set_internal (base_variable, find_symbol_value (new_alias), Qnil, 1);
{
- struct specbinding *p;
+ union specbinding *p;
for (p = specpdl_ptr; p > specpdl; )
if ((--p)->kind >= SPECPDL_LET
return base_variable;
}
+static union specbinding *
+default_toplevel_binding (Lisp_Object symbol)
+{
+ union specbinding *binding = NULL;
+ union specbinding *pdl = specpdl_ptr;
+ while (pdl > specpdl)
+ {
+ switch ((--pdl)->kind)
+ {
+ case SPECPDL_LET_DEFAULT:
+ case SPECPDL_LET:
+ if (EQ (specpdl_symbol (pdl), symbol))
+ binding = pdl;
+ break;
+ }
+ }
+ return binding;
+}
+
+DEFUN ("default-toplevel-value", Fdefault_toplevel_value, Sdefault_toplevel_value, 1, 1, 0,
+ doc: /* Return SYMBOL's toplevel default value.
+"Toplevel" means outside of any let binding. */)
+ (Lisp_Object symbol)
+{
+ union specbinding *binding = default_toplevel_binding (symbol);
+ Lisp_Object value
+ = binding ? specpdl_old_value (binding) : Fdefault_value (symbol);
+ if (!EQ (value, Qunbound))
+ return value;
+ xsignal1 (Qvoid_variable, symbol);
+}
+
+DEFUN ("set-default-toplevel-value", Fset_default_toplevel_value,
+ Sset_default_toplevel_value, 2, 2, 0,
+ doc: /* Set SYMBOL's toplevel default value to VALUE.
+"Toplevel" means outside of any let binding. */)
+ (Lisp_Object symbol, Lisp_Object value)
+{
+ union specbinding *binding = default_toplevel_binding (symbol);
+ if (binding)
+ set_specpdl_old_value (binding, value);
+ else
+ Fset_default (symbol, value);
+ return Qnil;
+}
DEFUN ("defvar", Fdefvar, Sdefvar, 1, UNEVALLED, 0,
doc: /* Define SYMBOL as a variable, and return SYMBOL.
usage: (defvar SYMBOL &optional INITVALUE DOCSTRING) */)
(Lisp_Object args)
{
- register Lisp_Object sym, tem, tail;
+ Lisp_Object sym, tem, tail;
- sym = Fcar (args);
- tail = Fcdr (args);
- if (!NILP (Fcdr (Fcdr (tail))))
- error ("Too many arguments");
+ sym = XCAR (args);
+ tail = XCDR (args);
- tem = Fdefault_boundp (sym);
- if (!NILP (tail))
+ if (CONSP (tail))
{
+ if (CONSP (XCDR (tail)) && CONSP (XCDR (XCDR (tail))))
+ error ("Too many arguments");
+
+ tem = Fdefault_boundp (sym);
+
/* Do it before evaluating the initial value, for self-references. */
XSYMBOL (sym)->declared_special = 1;
if (NILP (tem))
- Fset_default (sym, eval_sub (Fcar (tail)));
+ Fset_default (sym, eval_sub (XCAR (tail)));
else
{ /* Check if there is really a global binding rather than just a let
binding that shadows the global unboundness of the var. */
- struct specbinding *pdl = specpdl_ptr;
- while (pdl > specpdl)
+ union specbinding *binding = default_toplevel_binding (sym);
+ if (binding && EQ (specpdl_old_value (binding), Qunbound))
{
- if ((--pdl)->kind >= SPECPDL_LET
- && EQ (specpdl_symbol (pdl), sym)
- && EQ (specpdl_old_value (pdl), Qunbound))
- {
- message_with_string
- ("Warning: defvar ignored because %s is let-bound",
- SYMBOL_NAME (sym), 1);
- break;
- }
+ set_specpdl_old_value (binding, eval_sub (XCAR (tail)));
}
}
- tail = Fcdr (tail);
+ tail = XCDR (tail);
tem = Fcar (tail);
if (!NILP (tem))
{
usage: (defconst SYMBOL INITVALUE [DOCSTRING]) */)
(Lisp_Object args)
{
- register Lisp_Object sym, tem;
+ Lisp_Object sym, tem;
- sym = Fcar (args);
- if (!NILP (Fcdr (Fcdr (Fcdr (args)))))
+ sym = XCAR (args);
+ if (CONSP (Fcdr (XCDR (XCDR (args)))))
error ("Too many arguments");
- tem = eval_sub (Fcar (Fcdr (args)));
+ tem = eval_sub (Fcar (XCDR (args)));
if (!NILP (Vpurify_flag))
tem = Fpurecopy (tem);
Fset_default (sym, tem);
XSYMBOL (sym)->declared_special = 1;
- tem = Fcar (Fcdr (Fcdr (args)));
+ tem = Fcar (XCDR (XCDR (args)));
if (!NILP (tem))
{
if (!NILP (Vpurify_flag))
lexenv = Vinternal_interpreter_environment;
- varlist = Fcar (args);
+ varlist = XCAR (args);
while (CONSP (varlist))
{
QUIT;
varlist = XCDR (varlist);
}
UNGCPRO;
- val = Fprogn (Fcdr (args));
+ val = Fprogn (XCDR (args));
return unbind_to (count, val);
}
struct gcpro gcpro1, gcpro2;
USE_SAFE_ALLOCA;
- varlist = Fcar (args);
+ varlist = XCAR (args);
/* Make space to hold the values to give the bound variables. */
elt = Flength (varlist);
lexenv = Vinternal_interpreter_environment;
- varlist = Fcar (args);
+ varlist = XCAR (args);
for (argnum = 0; CONSP (varlist); varlist = XCDR (varlist))
{
Lisp_Object var;
/* Instantiate a new lexical environment. */
specbind (Qinternal_interpreter_environment, lexenv);
- elt = Fprogn (Fcdr (args));
+ elt = Fprogn (XCDR (args));
SAFE_FREE ();
return unbind_to (count, elt);
}
GCPRO2 (test, body);
- test = Fcar (args);
- body = Fcdr (args);
+ test = XCAR (args);
+ body = XCDR (args);
while (!NILP (eval_sub (test)))
{
QUIT;
struct gcpro gcpro1;
GCPRO1 (args);
- tag = eval_sub (Fcar (args));
+ tag = eval_sub (XCAR (args));
UNGCPRO;
- return internal_catch (tag, Fprogn, Fcdr (args));
+ return internal_catch (tag, Fprogn, XCDR (args));
}
+/* Assert that E is true, as a comment only. Use this instead of
+ eassert (E) when E contains variables that might be clobbered by a
+ longjmp. */
+
+#define clobbered_eassert(E) ((void) 0)
+
/* Set up a catch, then call C function FUNC on argument ARG.
FUNC should return a Lisp_Object.
This is how catches are done from within C code. */
internal_catch (Lisp_Object tag, Lisp_Object (*func) (Lisp_Object), Lisp_Object arg)
{
/* This structure is made part of the chain `catchlist'. */
- struct catchtag c;
+ struct handler *c;
/* Fill in the components of c, and put it on the list. */
- c.next = catchlist;
- c.tag = tag;
- c.val = Qnil;
- c.handlerlist = handlerlist;
- c.lisp_eval_depth = lisp_eval_depth;
- c.pdlcount = SPECPDL_INDEX ();
- c.poll_suppress_count = poll_suppress_count;
- c.interrupt_input_blocked = interrupt_input_blocked;
- c.gcpro = gcprolist;
- c.byte_stack = byte_stack_list;
- catchlist = &c;
+ PUSH_HANDLER (c, tag, CATCHER);
/* Call FUNC. */
- if (! sys_setjmp (c.jmp))
- c.val = (*func) (arg);
-
- /* Throw works by a longjmp that comes right here. */
- catchlist = c.next;
- return c.val;
+ if (! sys_setjmp (c->jmp))
+ {
+ Lisp_Object val = (*func) (arg);
+ clobbered_eassert (handlerlist == c);
+ handlerlist = handlerlist->next;
+ return val;
+ }
+ else
+ { /* Throw works by a longjmp that comes right here. */
+ Lisp_Object val = handlerlist->val;
+ clobbered_eassert (handlerlist == c);
+ handlerlist = handlerlist->next;
+ return val;
+ }
}
/* Unwind the specbind, catch, and handler stacks back to CATCH, and
This is used for correct unwinding in Fthrow and Fsignal. */
static _Noreturn void
-unwind_to_catch (struct catchtag *catch, Lisp_Object value)
+unwind_to_catch (struct handler *catch, Lisp_Object value)
{
bool last_time;
+ eassert (catch->next);
+
/* Save the value in the tag. */
catch->val = value;
do
{
- last_time = catchlist == catch;
-
/* Unwind the specpdl stack, and then restore the proper set of
handlers. */
- unbind_to (catchlist->pdlcount, Qnil);
- handlerlist = catchlist->handlerlist;
- catchlist = catchlist->next;
+ unbind_to (handlerlist->pdlcount, Qnil);
+ last_time = handlerlist == catch;
+ if (! last_time)
+ handlerlist = handlerlist->next;
}
while (! last_time);
- byte_stack_list = catch->byte_stack;
+ eassert (handlerlist == catch);
+
gcprolist = catch->gcpro;
#ifdef DEBUG_GCPRO
gcpro_level = gcprolist ? gcprolist->level + 1 : 0;
Both TAG and VALUE are evalled. */)
(register Lisp_Object tag, Lisp_Object value)
{
- register struct catchtag *c;
+ struct handler *c;
if (!NILP (tag))
- for (c = catchlist; c; c = c->next)
+ for (c = handlerlist; c; c = c->next)
{
- if (EQ (c->tag, tag))
+ if (c->type == CATCHER && EQ (c->tag_or_ch, tag))
unwind_to_catch (c, value);
}
xsignal2 (Qno_catch, tag, value);
Lisp_Object val;
ptrdiff_t count = SPECPDL_INDEX ();
- record_unwind_protect (Fprogn, Fcdr (args));
- val = eval_sub (Fcar (args));
+ record_unwind_protect (unwind_body, XCDR (args));
+ val = eval_sub (XCAR (args));
return unbind_to (count, val);
}
\f
usage: (condition-case VAR BODYFORM &rest HANDLERS) */)
(Lisp_Object args)
{
- Lisp_Object var = Fcar (args);
- Lisp_Object bodyform = Fcar (Fcdr (args));
- Lisp_Object handlers = Fcdr (Fcdr (args));
+ Lisp_Object var = XCAR (args);
+ Lisp_Object bodyform = XCAR (XCDR (args));
+ Lisp_Object handlers = XCDR (XCDR (args));
return internal_lisp_condition_case (var, bodyform, handlers);
}
Lisp_Object handlers)
{
Lisp_Object val;
- struct catchtag c;
- struct handler h;
+ struct handler *c;
+ struct handler *oldhandlerlist = handlerlist;
+ int clausenb = 0;
CHECK_SYMBOL (var);
for (val = handlers; CONSP (val); val = XCDR (val))
{
- Lisp_Object tem;
- tem = XCAR (val);
+ Lisp_Object tem = XCAR (val);
+ clausenb++;
if (! (NILP (tem)
|| (CONSP (tem)
&& (SYMBOLP (XCAR (tem))
SDATA (Fprin1_to_string (tem, Qt)));
}
- c.tag = Qnil;
- c.val = Qnil;
- c.handlerlist = handlerlist;
- c.lisp_eval_depth = lisp_eval_depth;
- c.pdlcount = SPECPDL_INDEX ();
- c.poll_suppress_count = poll_suppress_count;
- c.interrupt_input_blocked = interrupt_input_blocked;
- c.gcpro = gcprolist;
- c.byte_stack = byte_stack_list;
- if (sys_setjmp (c.jmp))
- {
- if (!NILP (h.var))
- specbind (h.var, c.val);
- val = Fprogn (Fcdr (h.chosen_clause));
-
- /* Note that this just undoes the binding of h.var; whoever
- longjumped to us unwound the stack to c.pdlcount before
- throwing. */
- unbind_to (c.pdlcount, Qnil);
- return val;
+ { /* The first clause is the one that should be checked first, so it should
+ be added to handlerlist last. So we build in `clauses' a table that
+ contains `handlers' but in reverse order. */
+ Lisp_Object *clauses = alloca (clausenb * sizeof (Lisp_Object *));
+ Lisp_Object *volatile clauses_volatile = clauses;
+ int i = clausenb;
+ for (val = handlers; CONSP (val); val = XCDR (val))
+ clauses[--i] = XCAR (val);
+ for (i = 0; i < clausenb; i++)
+ {
+ Lisp_Object clause = clauses[i];
+ Lisp_Object condition = XCAR (clause);
+ if (!CONSP (condition))
+ condition = Fcons (condition, Qnil);
+ PUSH_HANDLER (c, condition, CONDITION_CASE);
+ if (sys_setjmp (c->jmp))
+ {
+ ptrdiff_t count = SPECPDL_INDEX ();
+ Lisp_Object val = handlerlist->val;
+ Lisp_Object *chosen_clause = clauses_volatile;
+ for (c = handlerlist->next; c != oldhandlerlist; c = c->next)
+ chosen_clause++;
+ handlerlist = oldhandlerlist;
+ if (!NILP (var))
+ {
+ if (!NILP (Vinternal_interpreter_environment))
+ specbind (Qinternal_interpreter_environment,
+ Fcons (Fcons (var, val),
+ Vinternal_interpreter_environment));
+ else
+ specbind (var, val);
+ }
+ val = Fprogn (XCDR (*chosen_clause));
+ /* Note that this just undoes the binding of var; whoever
+ longjumped to us unwound the stack to c.pdlcount before
+ throwing. */
+ if (!NILP (var))
+ unbind_to (count, Qnil);
+ return val;
+ }
+ }
}
- c.next = catchlist;
- catchlist = &c;
-
- h.var = var;
- h.handler = handlers;
- h.next = handlerlist;
- h.tag = &c;
- handlerlist = &h;
val = eval_sub (bodyform);
- catchlist = c.next;
- handlerlist = h.next;
+ handlerlist = oldhandlerlist;
return val;
}
Lisp_Object (*hfun) (Lisp_Object))
{
Lisp_Object val;
- struct catchtag c;
- struct handler h;
-
- c.tag = Qnil;
- c.val = Qnil;
- c.handlerlist = handlerlist;
- c.lisp_eval_depth = lisp_eval_depth;
- c.pdlcount = SPECPDL_INDEX ();
- c.poll_suppress_count = poll_suppress_count;
- c.interrupt_input_blocked = interrupt_input_blocked;
- c.gcpro = gcprolist;
- c.byte_stack = byte_stack_list;
- if (sys_setjmp (c.jmp))
- {
- return (*hfun) (c.val);
- }
- c.next = catchlist;
- catchlist = &c;
- h.handler = handlers;
- h.var = Qnil;
- h.next = handlerlist;
- h.tag = &c;
- handlerlist = &h;
+ struct handler *c;
+
+ PUSH_HANDLER (c, handlers, CONDITION_CASE);
+ if (sys_setjmp (c->jmp))
+ {
+ Lisp_Object val = handlerlist->val;
+ clobbered_eassert (handlerlist == c);
+ handlerlist = handlerlist->next;
+ return (*hfun) (val);
+ }
val = (*bfun) ();
- catchlist = c.next;
- handlerlist = h.next;
+ clobbered_eassert (handlerlist == c);
+ handlerlist = handlerlist->next;
return val;
}
Lisp_Object handlers, Lisp_Object (*hfun) (Lisp_Object))
{
Lisp_Object val;
- struct catchtag c;
- struct handler h;
-
- c.tag = Qnil;
- c.val = Qnil;
- c.handlerlist = handlerlist;
- c.lisp_eval_depth = lisp_eval_depth;
- c.pdlcount = SPECPDL_INDEX ();
- c.poll_suppress_count = poll_suppress_count;
- c.interrupt_input_blocked = interrupt_input_blocked;
- c.gcpro = gcprolist;
- c.byte_stack = byte_stack_list;
- if (sys_setjmp (c.jmp))
- {
- return (*hfun) (c.val);
- }
- c.next = catchlist;
- catchlist = &c;
- h.handler = handlers;
- h.var = Qnil;
- h.next = handlerlist;
- h.tag = &c;
- handlerlist = &h;
+ struct handler *c;
+
+ PUSH_HANDLER (c, handlers, CONDITION_CASE);
+ if (sys_setjmp (c->jmp))
+ {
+ Lisp_Object val = handlerlist->val;
+ clobbered_eassert (handlerlist == c);
+ handlerlist = handlerlist->next;
+ return (*hfun) (val);
+ }
val = (*bfun) (arg);
- catchlist = c.next;
- handlerlist = h.next;
+ clobbered_eassert (handlerlist == c);
+ handlerlist = handlerlist->next;
return val;
}
Lisp_Object (*hfun) (Lisp_Object))
{
Lisp_Object val;
- struct catchtag c;
- struct handler h;
-
- c.tag = Qnil;
- c.val = Qnil;
- c.handlerlist = handlerlist;
- c.lisp_eval_depth = lisp_eval_depth;
- c.pdlcount = SPECPDL_INDEX ();
- c.poll_suppress_count = poll_suppress_count;
- c.interrupt_input_blocked = interrupt_input_blocked;
- c.gcpro = gcprolist;
- c.byte_stack = byte_stack_list;
- if (sys_setjmp (c.jmp))
- {
- return (*hfun) (c.val);
- }
- c.next = catchlist;
- catchlist = &c;
- h.handler = handlers;
- h.var = Qnil;
- h.next = handlerlist;
- h.tag = &c;
- handlerlist = &h;
+ struct handler *c;
+
+ PUSH_HANDLER (c, handlers, CONDITION_CASE);
+ if (sys_setjmp (c->jmp))
+ {
+ Lisp_Object val = handlerlist->val;
+ clobbered_eassert (handlerlist == c);
+ handlerlist = handlerlist->next;
+ return (*hfun) (val);
+ }
val = (*bfun) (arg1, arg2);
- catchlist = c.next;
- handlerlist = h.next;
+ clobbered_eassert (handlerlist == c);
+ handlerlist = handlerlist->next;
return val;
}
Lisp_Object *args))
{
Lisp_Object val;
- struct catchtag c;
- struct handler h;
-
- c.tag = Qnil;
- c.val = Qnil;
- c.handlerlist = handlerlist;
- c.lisp_eval_depth = lisp_eval_depth;
- c.pdlcount = SPECPDL_INDEX ();
- c.poll_suppress_count = poll_suppress_count;
- c.interrupt_input_blocked = interrupt_input_blocked;
- c.gcpro = gcprolist;
- c.byte_stack = byte_stack_list;
- if (sys_setjmp (c.jmp))
- {
- return (*hfun) (c.val, nargs, args);
- }
- c.next = catchlist;
- catchlist = &c;
- h.handler = handlers;
- h.var = Qnil;
- h.next = handlerlist;
- h.tag = &c;
- handlerlist = &h;
+ struct handler *c;
+
+ PUSH_HANDLER (c, handlers, CONDITION_CASE);
+ if (sys_setjmp (c->jmp))
+ {
+ Lisp_Object val = handlerlist->val;
+ clobbered_eassert (handlerlist == c);
+ handlerlist = handlerlist->next;
+ return (*hfun) (val, nargs, args);
+ }
val = (*bfun) (nargs, args);
- catchlist = c.next;
- handlerlist = h.next;
+ clobbered_eassert (handlerlist == c);
+ handlerlist = handlerlist->next;
return val;
}
struct handler *h;
immediate_quit = 0;
- abort_on_gc = 0;
- if (gc_in_progress || waiting_for_input)
+ if (waiting_for_input)
emacs_abort ();
#if 0 /* rms: I don't know why this was here,
Vsignaling_function = Qnil;
if (!NILP (error_symbol))
{
- struct specbinding *pdl = backtrace_next (backtrace_top ());
+ union specbinding *pdl = backtrace_next (backtrace_top ());
if (backtrace_p (pdl) && EQ (backtrace_function (pdl), Qerror))
pdl = backtrace_next (pdl);
if (backtrace_p (pdl))
for (h = handlerlist; h; h = h->next)
{
- clause = find_handler_clause (h->handler, conditions);
+ if (h->type != CONDITION_CASE)
+ continue;
+ clause = find_handler_clause (h->tag_or_ch, conditions);
if (!NILP (clause))
break;
}
|| NILP (clause)
/* A `debug' symbol in the handler list disables the normal
suppression of the debugger. */
- || (CONSP (clause) && CONSP (XCAR (clause))
- && !NILP (Fmemq (Qdebug, XCAR (clause))))
+ || (CONSP (clause) && CONSP (clause)
+ && !NILP (Fmemq (Qdebug, clause)))
/* Special handler that means "print a message and run debugger
if requested". */
- || EQ (h->handler, Qerror)))
+ || EQ (h->tag_or_ch, Qerror)))
{
bool debugger_called
= maybe_call_debugger (conditions, error_symbol, data);
Lisp_Object unwind_data
= (NILP (error_symbol) ? data : Fcons (error_symbol, data));
- h->chosen_clause = clause;
- unwind_to_catch (h->tag, unwind_data);
+ unwind_to_catch (h, unwind_data);
}
else
{
- if (catchlist != 0)
+ if (handlerlist != &handlerlist_sentinel)
+ /* FIXME: This will come right back here if there's no `top-level'
+ catcher. A better solution would be to abort here, and instead
+ add a catch-all condition handler so we never come here. */
Fthrow (Qtop_level, Qt);
}
}
if (!NILP (hare))
- arg = Fcons (arg, Qnil); /* Make it a list. */
+ arg = list1 (arg);
xsignal (Qerror, Fcons (build_string (s), arg));
}
/* RMS: What's this for? */
&& when_entered_debugger < num_nonmacro_input_events)
{
- call_debugger (Fcons (Qerror, Fcons (combined_data, Qnil)));
+ call_debugger (list2 (Qerror, combined_data));
return 1;
}
for (h = handlers; CONSP (h); h = XCDR (h))
{
Lisp_Object handler = XCAR (h);
- Lisp_Object condit, tem;
-
- if (!CONSP (handler))
- continue;
- condit = XCAR (handler);
- /* Handle a single condition name in handler HANDLER. */
- if (SYMBOLP (condit))
- {
- tem = Fmemq (Fcar (handler), conditions);
- if (!NILP (tem))
- return handler;
- }
- /* Handle a list of condition names in handler HANDLER. */
- else if (CONSP (condit))
- {
- Lisp_Object tail;
- for (tail = condit; CONSP (tail); tail = XCDR (tail))
- {
- tem = Fmemq (XCAR (tail), conditions);
- if (!NILP (tem))
- return handler;
- }
- }
+ if (!NILP (Fmemq (handler, conditions)))
+ return handlers;
}
return Qnil;
&& !AUTOLOADP (XSYMBOL (function)->function))
return Qnil;
- if (!NILP (Vpurify_flag) && EQ (docstring, make_number (0)))
- /* `read1' in lread.c has found the docstring starting with "\
- and assumed the docstring will be provided by Snarf-documentation, so it
- passed us 0 instead. But that leads to accidental sharing in purecopy's
- hash-consing, so we use a (hopefully) unique integer instead. */
- docstring = make_number (XHASH (function));
return Fdefalias (function,
list5 (Qautoload, file, docstring, interactive, type),
Qnil);
}
-Lisp_Object
+void
un_autoload (Lisp_Object oldqueue)
{
- register Lisp_Object queue, first, second;
+ Lisp_Object queue, first, second;
/* Queue to unwind is current value of Vautoload_queue.
oldqueue is the shadowed value to leave in Vautoload_queue. */
Ffset (first, second);
queue = XCDR (queue);
}
- return Qnil;
}
/* Load an autoloaded function.
\f
DEFUN ("eval", Feval, Seval, 1, 2, 0,
doc: /* Evaluate FORM and return its value.
-If LEXICAL is t, evaluate using lexical scoping. */)
+If LEXICAL is t, evaluate using lexical scoping.
+LEXICAL can also be an actual lexical environment, in the form of an
+alist mapping symbols to their value. */)
(Lisp_Object form, Lisp_Object lexical)
{
ptrdiff_t count = SPECPDL_INDEX ();
specbind (Qinternal_interpreter_environment,
- CONSP (lexical) || NILP (lexical) ? lexical : Fcons (Qt, Qnil));
+ CONSP (lexical) || NILP (lexical) ? lexical : list1 (Qt));
return unbind_to (count, eval_sub (form));
}
+/* Grow the specpdl stack by one entry.
+ The caller should have already initialized the entry.
+ Signal an error on stack overflow.
+
+ Make sure that there is always one unused entry past the top of the
+ stack, so that the just-initialized entry is safely unwound if
+ memory exhausted and an error is signaled here. Also, allocate a
+ never-used entry just before the bottom of the stack; sometimes its
+ address is taken. */
+
static void
grow_specpdl (void)
{
- register ptrdiff_t count = SPECPDL_INDEX ();
- ptrdiff_t max_size = min (max_specpdl_size, PTRDIFF_MAX);
- if (max_size <= specpdl_size)
+ specpdl_ptr++;
+
+ if (specpdl_ptr == specpdl + specpdl_size)
{
- if (max_specpdl_size < 400)
- max_size = max_specpdl_size = 400;
+ ptrdiff_t count = SPECPDL_INDEX ();
+ ptrdiff_t max_size = min (max_specpdl_size, PTRDIFF_MAX - 1000);
+ union specbinding *pdlvec = specpdl - 1;
+ ptrdiff_t pdlvecsize = specpdl_size + 1;
if (max_size <= specpdl_size)
- signal_error ("Variable binding depth exceeds max-specpdl-size", Qnil);
+ {
+ if (max_specpdl_size < 400)
+ max_size = max_specpdl_size = 400;
+ if (max_size <= specpdl_size)
+ signal_error ("Variable binding depth exceeds max-specpdl-size",
+ Qnil);
+ }
+ pdlvec = xpalloc (pdlvec, &pdlvecsize, 1, max_size + 1, sizeof *specpdl);
+ specpdl = pdlvec + 1;
+ specpdl_size = pdlvecsize - 1;
+ specpdl_ptr = specpdl + count;
}
- specpdl = xpalloc (specpdl, &specpdl_size, 1, max_size, sizeof *specpdl);
- specpdl_ptr = specpdl + count;
}
void
record_in_backtrace (Lisp_Object function, Lisp_Object *args, ptrdiff_t nargs)
{
eassert (nargs >= UNEVALLED);
- if (specpdl_ptr == specpdl + specpdl_size)
- grow_specpdl ();
- specpdl_ptr->kind = SPECPDL_BACKTRACE;
- specpdl_ptr->v.bt.function = function;
- specpdl_ptr->v.bt.args = args;
- specpdl_ptr->v.bt.nargs = nargs;
- specpdl_ptr->v.bt.debug_on_exit = false;
- specpdl_ptr++;
+ specpdl_ptr->bt.kind = SPECPDL_BACKTRACE;
+ specpdl_ptr->bt.debug_on_exit = false;
+ specpdl_ptr->bt.function = function;
+ specpdl_ptr->bt.args = args;
+ specpdl_ptr->bt.nargs = nargs;
+ grow_specpdl ();
}
/* Eval a sub-expression of the current expression (i.e. in the same
/* Optimize for no indirection. */
fun = original_fun;
- if (SYMBOLP (fun) && !NILP (fun)
- && (fun = XSYMBOL (fun)->function, SYMBOLP (fun)))
+ if (!SYMBOLP (fun))
+ fun = Ffunction (Fcons (fun, Qnil));
+ else if (!NILP (fun) && (fun = XSYMBOL (fun)->function, SYMBOLP (fun)))
fun = indirect_function (fun);
if (SUBRP (fun))
args_left = original_args;
numargs = Flength (args_left);
- check_cons_list ();
-
if (XINT (numargs) < XSUBR (fun)->min_args
|| (XSUBR (fun)->max_args >= 0
&& XSUBR (fun)->max_args < XINT (numargs)))
else
xsignal1 (Qinvalid_function, original_fun);
}
- check_cons_list ();
lisp_eval_depth--;
if (backtrace_debug_on_exit (specpdl_ptr - 1))
- val = call_debugger (Fcons (Qexit, Fcons (val, Qnil)));
+ val = call_debugger (list2 (Qexit, val));
specpdl_ptr--;
return val;
if (EQ (val, Qunbound) || NILP (val))
return ret;
- else if (!CONSP (val) || EQ (XCAR (val), Qlambda))
+ else if (!CONSP (val) || FUNCTIONP (val))
{
args[0] = val;
return funcall (nargs, args);
if (debug_on_next_call)
do_debug_on_call (Qlambda);
- check_cons_list ();
-
original_fun = args[0];
retry:
else if (EQ (funcar, Qautoload))
{
Fautoload_do_load (fun, original_fun, Qnil);
- check_cons_list ();
goto retry;
}
else
xsignal1 (Qinvalid_function, original_fun);
}
- check_cons_list ();
lisp_eval_depth--;
if (backtrace_debug_on_exit (specpdl_ptr - 1))
- val = call_debugger (Fcons (Qexit, Fcons (val, Qnil)));
+ val = call_debugger (list2 (Qexit, val));
specpdl_ptr--;
return val;
}
{
/* Don't do it again when we return to eval. */
set_backtrace_debug_on_exit (specpdl_ptr - 1, false);
- tem = call_debugger (Fcons (Qexit, Fcons (tem, Qnil)));
+ tem = call_debugger (list2 (Qexit, tem));
}
SAFE_FREE ();
return tem;
bool
let_shadows_buffer_binding_p (struct Lisp_Symbol *symbol)
{
- struct specbinding *p;
+ union specbinding *p;
Lisp_Object buf = Fcurrent_buffer ();
for (p = specpdl_ptr; p > specpdl; )
bool
let_shadows_global_binding_p (Lisp_Object symbol)
{
- struct specbinding *p;
+ union specbinding *p;
for (p = specpdl_ptr; p > specpdl; )
if ((--p)->kind >= SPECPDL_LET && EQ (specpdl_symbol (p), symbol))
return 0;
}
-/* `specpdl_ptr->symbol' is a field which describes which variable is
+/* `specpdl_ptr' describes which variable is
let-bound, so it can be properly undone when we unbind_to.
- It can have the following two shapes:
- - SYMBOL : if it's a plain symbol, it means that we have let-bound
- a symbol that is not buffer-local (at least at the time
- the let binding started). Note also that it should not be
+ It can be either a plain SPECPDL_LET or a SPECPDL_LET_LOCAL/DEFAULT.
+ - SYMBOL is the variable being bound. Note that it should not be
aliased (i.e. when let-binding V1 that's aliased to V2, we want
to record V2 here).
- - (SYMBOL WHERE . BUFFER) : this means that it is a let-binding for
- variable SYMBOL which can be buffer-local. WHERE tells us
- which buffer is affected (or nil if the let-binding affects the
- global value of the variable) and BUFFER tells us which buffer was
- current (i.e. if WHERE is non-nil, then BUFFER==WHERE, otherwise
- BUFFER did not yet have a buffer-local value). */
+ - WHERE tells us in which buffer the binding took place.
+ This is used for SPECPDL_LET_LOCAL bindings (i.e. bindings to a
+ buffer-local variable) as well as for SPECPDL_LET_DEFAULT bindings,
+ i.e. bindings to the default value of a variable which can be
+ buffer-local. */
void
specbind (Lisp_Object symbol, Lisp_Object value)
CHECK_SYMBOL (symbol);
sym = XSYMBOL (symbol);
- if (specpdl_ptr == specpdl + specpdl_size)
- grow_specpdl ();
start:
switch (sym->redirect)
case SYMBOL_PLAINVAL:
/* The most common case is that of a non-constant symbol with a
trivial value. Make that as fast as we can. */
- specpdl_ptr->kind = SPECPDL_LET;
- specpdl_ptr->v.let.symbol = symbol;
- specpdl_ptr->v.let.old_value = SYMBOL_VAL (sym);
- ++specpdl_ptr;
+ specpdl_ptr->let.kind = SPECPDL_LET;
+ specpdl_ptr->let.symbol = symbol;
+ specpdl_ptr->let.old_value = SYMBOL_VAL (sym);
+ grow_specpdl ();
if (!sym->constant)
SET_SYMBOL_VAL (sym, value);
else
case SYMBOL_FORWARDED:
{
Lisp_Object ovalue = find_symbol_value (symbol);
- specpdl_ptr->kind = SPECPDL_LET_LOCAL;
- specpdl_ptr->v.let.symbol = symbol;
- specpdl_ptr->v.let.old_value = ovalue;
- specpdl_ptr->v.let.where = Fcurrent_buffer ();
+ specpdl_ptr->let.kind = SPECPDL_LET_LOCAL;
+ specpdl_ptr->let.symbol = symbol;
+ specpdl_ptr->let.old_value = ovalue;
+ specpdl_ptr->let.where = Fcurrent_buffer ();
eassert (sym->redirect != SYMBOL_LOCALIZED
|| (EQ (SYMBOL_BLV (sym)->where, Fcurrent_buffer ())));
if (sym->redirect == SYMBOL_LOCALIZED)
{
if (!blv_found (SYMBOL_BLV (sym)))
- specpdl_ptr->kind = SPECPDL_LET_DEFAULT;
+ specpdl_ptr->let.kind = SPECPDL_LET_DEFAULT;
}
else if (BUFFER_OBJFWDP (SYMBOL_FWD (sym)))
{
happens with other buffer-local variables. */
if (NILP (Flocal_variable_p (symbol, Qnil)))
{
- specpdl_ptr->kind = SPECPDL_LET_DEFAULT;
- ++specpdl_ptr;
+ specpdl_ptr->let.kind = SPECPDL_LET_DEFAULT;
+ grow_specpdl ();
Fset_default (symbol, value);
return;
}
}
else
- specpdl_ptr->kind = SPECPDL_LET;
+ specpdl_ptr->let.kind = SPECPDL_LET;
- specpdl_ptr++;
+ grow_specpdl ();
set_internal (symbol, value, Qnil, 1);
break;
}
}
}
+/* Push unwind-protect entries of various types. */
+
void
-record_unwind_protect (Lisp_Object (*function) (Lisp_Object), Lisp_Object arg)
+record_unwind_protect (void (*function) (Lisp_Object), Lisp_Object arg)
{
- if (specpdl_ptr == specpdl + specpdl_size)
- grow_specpdl ();
- specpdl_ptr->kind = SPECPDL_UNWIND;
- specpdl_ptr->v.unwind.func = function;
- specpdl_ptr->v.unwind.arg = arg;
- specpdl_ptr++;
+ specpdl_ptr->unwind.kind = SPECPDL_UNWIND;
+ specpdl_ptr->unwind.func = function;
+ specpdl_ptr->unwind.arg = arg;
+ grow_specpdl ();
}
+void
+record_unwind_protect_ptr (void (*function) (void *), void *arg)
+{
+ specpdl_ptr->unwind_ptr.kind = SPECPDL_UNWIND_PTR;
+ specpdl_ptr->unwind_ptr.func = function;
+ specpdl_ptr->unwind_ptr.arg = arg;
+ grow_specpdl ();
+}
+
+void
+record_unwind_protect_int (void (*function) (int), int arg)
+{
+ specpdl_ptr->unwind_int.kind = SPECPDL_UNWIND_INT;
+ specpdl_ptr->unwind_int.func = function;
+ specpdl_ptr->unwind_int.arg = arg;
+ grow_specpdl ();
+}
+
+void
+record_unwind_protect_void (void (*function) (void))
+{
+ specpdl_ptr->unwind_void.kind = SPECPDL_UNWIND_VOID;
+ specpdl_ptr->unwind_void.func = function;
+ grow_specpdl ();
+}
+
+static void
+do_nothing (void)
+{}
+
+/* Push an unwind-protect entry that does nothing, so that
+ set_unwind_protect_ptr can overwrite it later. */
+
+void
+record_unwind_protect_nothing (void)
+{
+ record_unwind_protect_void (do_nothing);
+}
+
+/* Clear the unwind-protect entry COUNT, so that it does nothing.
+ It need not be at the top of the stack. */
+
+void
+clear_unwind_protect (ptrdiff_t count)
+{
+ union specbinding *p = specpdl + count;
+ p->unwind_void.kind = SPECPDL_UNWIND_VOID;
+ p->unwind_void.func = do_nothing;
+}
+
+/* Set the unwind-protect entry COUNT so that it invokes FUNC (ARG).
+ It need not be at the top of the stack. Discard the entry's
+ previous value without invoking it. */
+
+void
+set_unwind_protect (ptrdiff_t count, void (*func) (Lisp_Object),
+ Lisp_Object arg)
+{
+ union specbinding *p = specpdl + count;
+ p->unwind.kind = SPECPDL_UNWIND;
+ p->unwind.func = func;
+ p->unwind.arg = arg;
+}
+
+void
+set_unwind_protect_ptr (ptrdiff_t count, void (*func) (void *), void *arg)
+{
+ union specbinding *p = specpdl + count;
+ p->unwind_ptr.kind = SPECPDL_UNWIND_PTR;
+ p->unwind_ptr.func = func;
+ p->unwind_ptr.arg = arg;
+}
+
+/* Pop and execute entries from the unwind-protect stack until the
+ depth COUNT is reached. Return VALUE. */
+
Lisp_Object
unbind_to (ptrdiff_t count, Lisp_Object value)
{
while (specpdl_ptr != specpdl + count)
{
- /* Copy the binding, and decrement specpdl_ptr, before we do
- the work to unbind it. We decrement first
- so that an error in unbinding won't try to unbind
- the same entry again, and we copy the binding first
- in case more bindings are made during some of the code we run. */
+ /* Decrement specpdl_ptr before we do the work to unbind it, so
+ that an error in unbinding won't try to unbind the same entry
+ again. Take care to copy any parts of the binding needed
+ before invoking any code that can make more bindings. */
- struct specbinding this_binding;
- this_binding = *--specpdl_ptr;
+ specpdl_ptr--;
- switch (this_binding.kind)
+ switch (specpdl_ptr->kind)
{
case SPECPDL_UNWIND:
- (*specpdl_func (&this_binding)) (specpdl_arg (&this_binding));
+ specpdl_ptr->unwind.func (specpdl_ptr->unwind.arg);
break;
- case SPECPDL_LET:
- /* If variable has a trivial value (no forwarding), we can
- just set it. No need to check for constant symbols here,
- since that was already done by specbind. */
- if (XSYMBOL (specpdl_symbol (&this_binding))->redirect
- == SYMBOL_PLAINVAL)
- SET_SYMBOL_VAL (XSYMBOL (specpdl_symbol (&this_binding)),
- specpdl_old_value (&this_binding));
- else
- /* NOTE: we only ever come here if make_local_foo was used for
- the first time on this var within this let. */
- Fset_default (specpdl_symbol (&this_binding),
- specpdl_old_value (&this_binding));
+ case SPECPDL_UNWIND_PTR:
+ specpdl_ptr->unwind_ptr.func (specpdl_ptr->unwind_ptr.arg);
+ break;
+ case SPECPDL_UNWIND_INT:
+ specpdl_ptr->unwind_int.func (specpdl_ptr->unwind_int.arg);
+ break;
+ case SPECPDL_UNWIND_VOID:
+ specpdl_ptr->unwind_void.func ();
break;
case SPECPDL_BACKTRACE:
break;
- case SPECPDL_LET_LOCAL:
+ case SPECPDL_LET:
+ { /* If variable has a trivial value (no forwarding), we can
+ just set it. No need to check for constant symbols here,
+ since that was already done by specbind. */
+ struct Lisp_Symbol *sym = XSYMBOL (specpdl_symbol (specpdl_ptr));
+ if (sym->redirect == SYMBOL_PLAINVAL)
+ {
+ SET_SYMBOL_VAL (sym, specpdl_old_value (specpdl_ptr));
+ break;
+ }
+ else
+ { /* FALLTHROUGH!!
+ NOTE: we only ever come here if make_local_foo was used for
+ the first time on this var within this let. */
+ }
+ }
case SPECPDL_LET_DEFAULT:
- { /* If the symbol is a list, it is really (SYMBOL WHERE
- . CURRENT-BUFFER) where WHERE is either nil, a buffer, or a
- frame. If WHERE is a buffer or frame, this indicates we
- bound a variable that had a buffer-local or frame-local
- binding. WHERE nil means that the variable had the default
- value when it was bound. CURRENT-BUFFER is the buffer that
- was current when the variable was bound. */
- Lisp_Object symbol = specpdl_symbol (&this_binding);
- Lisp_Object where = specpdl_where (&this_binding);
+ Fset_default (specpdl_symbol (specpdl_ptr),
+ specpdl_old_value (specpdl_ptr));
+ break;
+ case SPECPDL_LET_LOCAL:
+ {
+ Lisp_Object symbol = specpdl_symbol (specpdl_ptr);
+ Lisp_Object where = specpdl_where (specpdl_ptr);
+ Lisp_Object old_value = specpdl_old_value (specpdl_ptr);
eassert (BUFFERP (where));
- if (this_binding.kind == SPECPDL_LET_DEFAULT)
- Fset_default (symbol, specpdl_old_value (&this_binding));
/* If this was a local binding, reset the value in the appropriate
buffer, but only if that buffer's binding still exists. */
- else if (!NILP (Flocal_variable_p (symbol, where)))
- set_internal (symbol, specpdl_old_value (&this_binding),
- where, 1);
+ if (!NILP (Flocal_variable_p (symbol, where)))
+ set_internal (symbol, old_value, where, 1);
}
break;
}
The debugger is entered when that frame exits, if the flag is non-nil. */)
(Lisp_Object level, Lisp_Object flag)
{
- struct specbinding *pdl = backtrace_top ();
+ union specbinding *pdl = backtrace_top ();
register EMACS_INT i;
CHECK_NUMBER (level);
Output stream used is value of `standard-output'. */)
(void)
{
- struct specbinding *pdl = backtrace_top ();
+ union specbinding *pdl = backtrace_top ();
Lisp_Object tem;
Lisp_Object old_print_level = Vprint_level;
return Qnil;
}
-DEFUN ("backtrace-frame", Fbacktrace_frame, Sbacktrace_frame, 1, 1, NULL,
+static union specbinding *
+get_backtrace_frame (Lisp_Object nframes, Lisp_Object base)
+{
+ union specbinding *pdl = backtrace_top ();
+ register EMACS_INT i;
+
+ CHECK_NATNUM (nframes);
+
+ if (!NILP (base))
+ { /* Skip up to `base'. */
+ base = Findirect_function (base, Qt);
+ while (backtrace_p (pdl)
+ && !EQ (base, Findirect_function (backtrace_function (pdl), Qt)))
+ pdl = backtrace_next (pdl);
+ }
+
+ /* Find the frame requested. */
+ for (i = XFASTINT (nframes); i > 0 && backtrace_p (pdl); i--)
+ pdl = backtrace_next (pdl);
+
+ return pdl;
+}
+
+DEFUN ("backtrace-frame", Fbacktrace_frame, Sbacktrace_frame, 1, 2, NULL,
doc: /* Return the function and arguments NFRAMES up from current execution point.
If that frame has not evaluated the arguments yet (or is a special form),
the value is (nil FUNCTION ARG-FORMS...).
A &rest arg is represented as the tail of the list ARG-VALUES.
FUNCTION is whatever was supplied as car of evaluated list,
or a lambda expression for macro calls.
-If NFRAMES is more than the number of frames, the value is nil. */)
- (Lisp_Object nframes)
+If NFRAMES is more than the number of frames, the value is nil.
+If BASE is non-nil, it should be a function and NFRAMES counts from its
+nearest activation frame. */)
+ (Lisp_Object nframes, Lisp_Object base)
{
- struct specbinding *pdl = backtrace_top ();
- register EMACS_INT i;
-
- CHECK_NATNUM (nframes);
-
- /* Find the frame requested. */
- for (i = 0; backtrace_p (pdl) && i < XFASTINT (nframes); i++)
- pdl = backtrace_next (pdl);
+ union specbinding *pdl = get_backtrace_frame (nframes, base);
if (!backtrace_p (pdl))
return Qnil;
}
}
-\f
-void
-mark_specpdl (void)
+/* For backtrace-eval, we want to temporarily unwind the last few elements of
+ the specpdl stack, and then rewind them. We store the pre-unwind values
+ directly in the pre-existing specpdl elements (i.e. we swap the current
+ value and the old value stored in the specpdl), kind of like the inplace
+ pointer-reversal trick. As it turns out, the rewind does the same as the
+ unwind, except it starts from the other end of the specpdl stack, so we use
+ the same function for both unwind and rewind. */
+static void
+backtrace_eval_unrewind (int distance)
{
- struct specbinding *pdl;
- for (pdl = specpdl; pdl != specpdl_ptr; pdl++)
+ union specbinding *tmp = specpdl_ptr;
+ int step = -1;
+ if (distance < 0)
+ { /* It's a rewind rather than unwind. */
+ tmp += distance - 1;
+ step = 1;
+ distance = -distance;
+ }
+
+ for (; distance > 0; distance--)
{
- switch (pdl->kind)
+ tmp += step;
+ /* */
+ switch (tmp->kind)
{
+ /* FIXME: Ideally we'd like to "temporarily unwind" (some of) those
+ unwind_protect, but the problem is that we don't know how to
+ rewind them afterwards. */
case SPECPDL_UNWIND:
- mark_object (specpdl_arg (pdl));
- break;
+ case SPECPDL_UNWIND_PTR:
+ case SPECPDL_UNWIND_INT:
+ case SPECPDL_UNWIND_VOID:
case SPECPDL_BACKTRACE:
+ break;
+ case SPECPDL_LET:
+ { /* If variable has a trivial value (no forwarding), we can
+ just set it. No need to check for constant symbols here,
+ since that was already done by specbind. */
+ struct Lisp_Symbol *sym = XSYMBOL (specpdl_symbol (tmp));
+ if (sym->redirect == SYMBOL_PLAINVAL)
+ {
+ Lisp_Object old_value = specpdl_old_value (tmp);
+ set_specpdl_old_value (tmp, SYMBOL_VAL (sym));
+ SET_SYMBOL_VAL (sym, old_value);
+ break;
+ }
+ else
+ { /* FALLTHROUGH!!
+ NOTE: we only ever come here if make_local_foo was used for
+ the first time on this var within this let. */
+ }
+ }
+ case SPECPDL_LET_DEFAULT:
{
- ptrdiff_t nargs = backtrace_nargs (pdl);
- mark_object (backtrace_function (pdl));
- if (nargs == UNEVALLED)
- nargs = 1;
- while (nargs--)
- mark_object (backtrace_args (pdl)[nargs]);
+ Lisp_Object sym = specpdl_symbol (tmp);
+ Lisp_Object old_value = specpdl_old_value (tmp);
+ set_specpdl_old_value (tmp, Fdefault_value (sym));
+ Fset_default (sym, old_value);
}
break;
- case SPECPDL_LET_DEFAULT:
case SPECPDL_LET_LOCAL:
- mark_object (specpdl_where (pdl));
- case SPECPDL_LET:
- mark_object (specpdl_symbol (pdl));
- mark_object (specpdl_old_value (pdl));
+ {
+ Lisp_Object symbol = specpdl_symbol (tmp);
+ Lisp_Object where = specpdl_where (tmp);
+ Lisp_Object old_value = specpdl_old_value (tmp);
+ eassert (BUFFERP (where));
+
+ /* If this was a local binding, reset the value in the appropriate
+ buffer, but only if that buffer's binding still exists. */
+ if (!NILP (Flocal_variable_p (symbol, where)))
+ {
+ set_specpdl_old_value
+ (tmp, Fbuffer_local_value (symbol, where));
+ set_internal (symbol, old_value, where, 1);
+ }
+ }
+ break;
}
}
}
+DEFUN ("backtrace-eval", Fbacktrace_eval, Sbacktrace_eval, 2, 3, NULL,
+ doc: /* Evaluate EXP in the context of some activation frame.
+NFRAMES and BASE specify the activation frame to use, as in `backtrace-frame'. */)
+ (Lisp_Object exp, Lisp_Object nframes, Lisp_Object base)
+{
+ union specbinding *pdl = get_backtrace_frame (nframes, base);
+ ptrdiff_t count = SPECPDL_INDEX ();
+ ptrdiff_t distance = specpdl_ptr - pdl;
+ eassert (distance >= 0);
+
+ if (!backtrace_p (pdl))
+ error ("Activation frame not found!");
+
+ backtrace_eval_unrewind (distance);
+ record_unwind_protect_int (backtrace_eval_unrewind, -distance);
+
+ /* Use eval_sub rather than Feval since the main motivation behind
+ backtrace-eval is to be able to get/set the value of lexical variables
+ from the debugger. */
+ return unbind_to (count, eval_sub (exp));
+}
+
+DEFUN ("backtrace--locals", Fbacktrace__locals, Sbacktrace__locals, 1, 2, NULL,
+ doc: /* Return names and values of local variables of a stack frame.
+NFRAMES and BASE specify the activation frame to use, as in `backtrace-frame'. */)
+ (Lisp_Object nframes, Lisp_Object base)
+{
+ union specbinding *frame = get_backtrace_frame (nframes, base);
+ union specbinding *prevframe
+ = get_backtrace_frame (make_number (XFASTINT (nframes) - 1), base);
+ ptrdiff_t distance = specpdl_ptr - frame;
+ Lisp_Object result = Qnil;
+ eassert (distance >= 0);
+
+ if (!backtrace_p (prevframe))
+ error ("Activation frame not found!");
+ if (!backtrace_p (frame))
+ error ("Activation frame not found!");
+
+ /* The specpdl entries normally contain the symbol being bound along with its
+ `old_value', so it can be restored. The new value to which it is bound is
+ available in one of two places: either in the current value of the
+ variable (if it hasn't been rebound yet) or in the `old_value' slot of the
+ next specpdl entry for it.
+ `backtrace_eval_unrewind' happens to swap the role of `old_value'
+ and "new value", so we abuse it here, to fetch the new value.
+ It's ugly (we'd rather not modify global data) and a bit inefficient,
+ but it does the job for now. */
+ backtrace_eval_unrewind (distance);
+
+ /* Grab values. */
+ {
+ union specbinding *tmp = prevframe;
+ for (; tmp > frame; tmp--)
+ {
+ switch (tmp->kind)
+ {
+ case SPECPDL_LET:
+ case SPECPDL_LET_DEFAULT:
+ case SPECPDL_LET_LOCAL:
+ {
+ Lisp_Object sym = specpdl_symbol (tmp);
+ Lisp_Object val = specpdl_old_value (tmp);
+ if (EQ (sym, Qinternal_interpreter_environment))
+ {
+ Lisp_Object env = val;
+ for (; CONSP (env); env = XCDR (env))
+ {
+ Lisp_Object binding = XCAR (env);
+ if (CONSP (binding))
+ result = Fcons (Fcons (XCAR (binding),
+ XCDR (binding)),
+ result);
+ }
+ }
+ else
+ result = Fcons (Fcons (sym, val), result);
+ }
+ }
+ }
+ }
+
+ /* Restore values from specpdl to original place. */
+ backtrace_eval_unrewind (-distance);
+
+ return result;
+}
+
+\f
void
get_backtrace (Lisp_Object array)
{
- struct specbinding *pdl = backtrace_next (backtrace_top ());
+ union specbinding *pdl = backtrace_next (backtrace_top ());
ptrdiff_t i = 0, asize = ASIZE (array);
/* Copy the backtrace contents into working memory. */
Lisp_Object backtrace_top_function (void)
{
- struct specbinding *pdl = backtrace_top ();
+ union specbinding *pdl = backtrace_top ();
return (backtrace_p (pdl) ? backtrace_function (pdl) : Qnil);
}
an error is signaled.
You can safely use a value considerably larger than the default value,
if that proves inconveniently small. However, if you increase it too far,
-Emacs could run out of memory trying to make the stack bigger. */);
+Emacs could run out of memory trying to make the stack bigger.
+Note that this limit may be silently increased by the debugger
+if `debug-on-error' or `debug-on-quit' is set. */);
DEFVAR_INT ("max-lisp-eval-depth", max_lisp_eval_depth,
doc: /* Limit on depth in `eval', `apply' and `funcall' before error.
defsubr (&Ssetq);
defsubr (&Squote);
defsubr (&Sfunction);
+ defsubr (&Sdefault_toplevel_value);
+ defsubr (&Sset_default_toplevel_value);
defsubr (&Sdefvar);
defsubr (&Sdefvaralias);
defsubr (&Sdefconst);
defsubr (&Sbacktrace_debug);
defsubr (&Sbacktrace);
defsubr (&Sbacktrace_frame);
+ defsubr (&Sbacktrace_eval);
+ defsubr (&Sbacktrace__locals);
defsubr (&Sspecial_variable_p);
defsubr (&Sfunctionp);
}