/* Evaluator for GNU Emacs Lisp interpreter.
- Copyright (C) 1985-1987, 1993-1995, 1999-2011 Free Software Foundation, Inc.
+ Copyright (C) 1985-1987, 1993-1995, 1999-2012 Free Software Foundation, Inc.
This file is part of GNU Emacs.
int handling_signal;
+/* If non-nil, Lisp code must not be run since some part of Emacs is
+ in an inconsistent state. Currently, x-create-frame uses this to
+ avoid triggering window-configuration-change-hook while the new
+ frame is half-initialized. */
+Lisp_Object inhibit_lisp_code;
+
static Lisp_Object funcall_lambda (Lisp_Object, ptrdiff_t, Lisp_Object *);
static void unwind_to_catch (struct catchtag *, Lisp_Object) NO_RETURN;
static int interactive_p (int);
void
init_eval_once (void)
{
- specpdl_size = 50;
- specpdl = (struct specbinding *) xmalloc (specpdl_size * sizeof (struct specbinding));
+ enum { size = 50 };
+ specpdl = (struct specbinding *) xmalloc (size * sizeof (struct specbinding));
+ specpdl_size = size;
specpdl_ptr = specpdl;
/* Don't forget to update docs (lispref node "Local Variables"). */
max_specpdl_size = 1300; /* 1000 is not enough for CEDET's c-by.el. */
if (lisp_eval_depth + 40 > max_lisp_eval_depth)
max_lisp_eval_depth = lisp_eval_depth + 40;
- if (SPECPDL_INDEX () + 100 > max_specpdl_size)
+ if (max_specpdl_size - 100 < SPECPDL_INDEX ())
max_specpdl_size = SPECPDL_INDEX () + 100;
#ifdef HAVE_WINDOW_SYSTEM
args_left = Fcdr (Fcdr (args_left));
}
- while (!NILP(args_left));
+ while (!NILP (args_left));
UNGCPRO;
return val;
DEFUN ("quote", Fquote, Squote, 1, UNEVALLED, 0,
doc: /* Return the argument, without evaluating it. `(quote x)' yields `x'.
+Warning: `quote' does not construct its return value, but just returns
+the value that was pre-constructed by the Lisp reader (see info node
+`(elisp)Printed Representation').
+This means that '(a . b) is not identical to (cons 'a 'b): the former
+does not cons. Quoting should be reserved for constants that will
+never be modified by side-effects, unless you like self-modifying code.
+See the common pitfall in info node `(elisp)Rearrangement' for an example
+of unexpected results when a quoted object is modified.
usage: (quote ARG) */)
(Lisp_Object args)
{
DEFUN ("defvar", Fdefvar, Sdefvar, 1, UNEVALLED, 0,
doc: /* Define SYMBOL as a variable, and return SYMBOL.
-You are not required to define a variable in order to use it,
-but the definition can supply documentation and an initial value
-in a way that tags can recognize.
-
-INITVALUE is evaluated, and used to set SYMBOL, only if SYMBOL's value is void.
-If SYMBOL is buffer-local, its default value is what is set;
- buffer-local values are not affected.
-INITVALUE and DOCSTRING are optional.
-If DOCSTRING starts with *, this variable is identified as a user option.
- This means that M-x set-variable recognizes it.
- See also `user-variable-p'.
+You are not required to define a variable in order to use it, but
+defining it lets you supply an initial value and documentation, which
+can be referred to by the Emacs help facilities and other programming
+tools. The `defvar' form also declares the variable as \"special\",
+so that it is always dynamically bound even if `lexical-binding' is t.
+
+The optional argument INITVALUE is evaluated, and used to set SYMBOL,
+only if SYMBOL's value is void. If SYMBOL is buffer-local, its
+default value is what is set; buffer-local values are not affected.
If INITVALUE is missing, SYMBOL's value is not set.
If SYMBOL has a local binding, then this form affects the local
`defcustom', you should always load that file _outside_ any bindings
for these variables. \(`defconst' and `defcustom' behave similarly in
this respect.)
+
+The optional argument DOCSTRING is a documentation string for the
+variable.
+
+To define a user option, use `defcustom' instead of `defvar'.
usage: (defvar SYMBOL &optional INITVALUE DOCSTRING) */)
(Lisp_Object args)
{
DEFUN ("defconst", Fdefconst, Sdefconst, 2, UNEVALLED, 0,
doc: /* Define SYMBOL as a constant variable.
-The intent is that neither programs nor users should ever change this value.
-Always sets the value of SYMBOL to the result of evalling INITVALUE.
-If SYMBOL is buffer-local, its default value is what is set;
- buffer-local values are not affected.
-DOCSTRING is optional.
-
-If SYMBOL has a local binding, then this form sets the local binding's
-value. However, you should normally not make local bindings for
-variables defined with this form.
+This declares that neither programs nor users should ever change the
+value. This constancy is not actually enforced by Emacs Lisp, but
+SYMBOL is marked as a special variable so that it is never lexically
+bound.
+
+The `defconst' form always sets the value of SYMBOL to the result of
+evalling INITVALUE. If SYMBOL is buffer-local, its default value is
+what is set; buffer-local values are not affected. If SYMBOL has a
+local binding, then this form sets the local binding's value.
+However, you should normally not make local bindings for variables
+defined with this form.
+
+The optional DOCSTRING specifies the variable's documentation string.
usage: (defconst SYMBOL INITVALUE [DOCSTRING]) */)
(Lisp_Object args)
{
return sym;
}
-/* Error handler used in Fuser_variable_p. */
-static Lisp_Object
-user_variable_p_eh (Lisp_Object ignore)
-{
- return Qnil;
-}
-
-static Lisp_Object
-lisp_indirect_variable (Lisp_Object sym)
-{
- struct Lisp_Symbol *s = indirect_variable (XSYMBOL (sym));
- XSETSYMBOL (sym, s);
- return sym;
-}
-
-DEFUN ("user-variable-p", Fuser_variable_p, Suser_variable_p, 1, 1, 0,
- doc: /* Return t if VARIABLE is intended to be set and modified by users.
-\(The alternative is a variable used internally in a Lisp program.)
-A variable is a user variable if
-\(1) the first character of its documentation is `*', or
-\(2) it is customizable (its property list contains a non-nil value
- of `standard-value' or `custom-autoload'), or
-\(3) it is an alias for another user variable.
-Return nil if VARIABLE is an alias and there is a loop in the
-chain of symbols. */)
- (Lisp_Object variable)
-{
- Lisp_Object documentation;
-
- if (!SYMBOLP (variable))
- return Qnil;
-
- /* If indirect and there's an alias loop, don't check anything else. */
- if (XSYMBOL (variable)->redirect == SYMBOL_VARALIAS
- && NILP (internal_condition_case_1 (lisp_indirect_variable, variable,
- Qt, user_variable_p_eh)))
- return Qnil;
-
- while (1)
- {
- documentation = Fget (variable, Qvariable_documentation);
- if (INTEGERP (documentation) && XINT (documentation) < 0)
- return Qt;
- if (STRINGP (documentation)
- && ((unsigned char) SREF (documentation, 0) == '*'))
- return Qt;
- /* If it is (STRING . INTEGER), a negative integer means a user variable. */
- if (CONSP (documentation)
- && STRINGP (XCAR (documentation))
- && INTEGERP (XCDR (documentation))
- && XINT (XCDR (documentation)) < 0)
- return Qt;
- /* Customizable? See `custom-variable-p'. */
- if ((!NILP (Fget (variable, intern ("standard-value"))))
- || (!NILP (Fget (variable, intern ("custom-autoload")))))
- return Qt;
-
- if (!(XSYMBOL (variable)->redirect == SYMBOL_VARALIAS))
- return Qnil;
-
- /* An indirect variable? Let's follow the chain. */
- XSETSYMBOL (variable, SYMBOL_ALIAS (XSYMBOL (variable)));
- }
-}
\f
DEFUN ("let*", FletX, SletX, 1, UNEVALLED, 0,
doc: /* Bind variables according to VARLIST then eval BODY.
if CONDITION-NAME is one of the error's condition names.
If an error happens, the first applicable handler is run.
-The car of a handler may be a list of condition names
-instead of a single condition name. Then it handles all of them.
+The car of a handler may be a list of condition names instead of a
+single condition name; then it handles all of them. If the special
+condition name `debug' is present in this list, it allows another
+condition in the list to run the debugger if `debug-on-error' and the
+other usual mechanisms says it should (otherwise, `condition-case'
+suppresses the debugger).
When a handler handles an error, control returns to the `condition-case'
and it executes the handler's BODY...
struct catchtag c;
struct handler h;
- /* Since Fsignal will close off all calls to x_catch_errors,
- we will get the wrong results if some are not closed now. */
-#if HAVE_X_WINDOWS
- if (x_catching_errors ())
- abort ();
-#endif
-
c.tag = Qnil;
c.val = Qnil;
c.backlist = backtrace_list;
struct catchtag c;
struct handler h;
- /* Since Fsignal will close off all calls to x_catch_errors,
- we will get the wrong results if some are not closed now. */
-#if HAVE_X_WINDOWS
- if (x_catching_errors ())
- abort ();
-#endif
-
c.tag = Qnil;
c.val = Qnil;
c.backlist = backtrace_list;
struct catchtag c;
struct handler h;
- /* Since Fsignal will close off all calls to x_catch_errors,
- we will get the wrong results if some are not closed now. */
-#if HAVE_X_WINDOWS
- if (x_catching_errors ())
- abort ();
-#endif
-
c.tag = Qnil;
c.val = Qnil;
c.backlist = backtrace_list;
struct catchtag c;
struct handler h;
- /* Since Fsignal will close off all calls to x_catch_errors,
- we will get the wrong results if some are not closed now. */
-#if HAVE_X_WINDOWS
- if (x_catching_errors ())
- abort ();
-#endif
-
c.tag = Qnil;
c.val = Qnil;
c.backlist = backtrace_list;
static int maybe_call_debugger (Lisp_Object conditions, Lisp_Object sig,
Lisp_Object data);
+void
+process_quit_flag (void)
+{
+ Lisp_Object flag = Vquit_flag;
+ Vquit_flag = Qnil;
+ if (EQ (flag, Qkill_emacs))
+ Fkill_emacs (Qnil);
+ if (EQ (Vthrow_on_input, flag))
+ Fthrow (Vthrow_on_input, Qt);
+ Fsignal (Qquit, Qnil);
+}
+
DEFUN ("signal", Fsignal, Ssignal, 2, 2, 0,
doc: /* Signal an error. Args are ERROR-SYMBOL and associated DATA.
This function does not return.
&& (!NILP (Vdebug_on_signal)
/* If no handler is present now, try to run the debugger. */
|| 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))))
/* Special handler that means "print a message and run debugger
if requested". */
|| EQ (h->handler, Qerror)))
verror (const char *m, va_list ap)
{
char buf[4000];
- size_t size = sizeof buf;
- size_t size_max = STRING_BYTES_BOUND + 1;
- size_t mlen = strlen (m);
+ ptrdiff_t size = sizeof buf;
+ ptrdiff_t size_max = STRING_BYTES_BOUND + 1;
char *buffer = buf;
- size_t used;
+ ptrdiff_t used;
Lisp_Object string;
- while (1)
- {
- va_list ap_copy;
- va_copy (ap_copy, ap);
- used = doprnt (buffer, size, m, m + mlen, ap_copy);
- va_end (ap_copy);
-
- /* Note: the -1 below is because `doprnt' returns the number of bytes
- excluding the terminating null byte, and it always terminates with a
- null byte, even when producing a truncated message. */
- if (used < size - 1)
- break;
- if (size <= size_max / 2)
- size *= 2;
- else if (size < size_max)
- size = size_max;
- else
- break; /* and leave the message truncated */
-
- if (buffer != buf)
- xfree (buffer);
- buffer = (char *) xmalloc (size);
- }
-
+ used = evxprintf (&buffer, &size, buf, size_max, m, ap);
string = make_string (buffer, used);
if (buffer != buf)
xfree (buffer);
We used to use 0 here, but that leads to accidental sharing in
purecopy's hash-consing, so we use a (hopefully) unique integer
instead. */
- docstring = make_number (XPNTR (function));
+ docstring = make_number (XUNTAG (function, Lisp_Symbol));
return Ffset (function,
Fpurecopy (list5 (Qautoload, file, docstring,
interactive, type)));
grow_specpdl (void)
{
register int count = SPECPDL_INDEX ();
- if (specpdl_size >= max_specpdl_size)
+ int max_size =
+ min (max_specpdl_size,
+ min (max (PTRDIFF_MAX, SIZE_MAX) / sizeof (struct specbinding),
+ INT_MAX));
+ int size;
+ if (max_size <= specpdl_size)
{
if (max_specpdl_size < 400)
- max_specpdl_size = 400;
- if (specpdl_size >= max_specpdl_size)
+ max_size = max_specpdl_size = 400;
+ if (max_size <= specpdl_size)
signal_error ("Variable binding depth exceeds max-specpdl-size", Qnil);
}
- specpdl_size *= 2;
- if (specpdl_size > max_specpdl_size)
- specpdl_size = max_specpdl_size;
- specpdl = (struct specbinding *) xrealloc (specpdl, specpdl_size * sizeof (struct specbinding));
+ size = specpdl_size < max_size / 2 ? 2 * specpdl_size : max_size;
+ specpdl = xnrealloc (specpdl, size, sizeof *specpdl);
+ specpdl_size = size;
specpdl_ptr = specpdl + count;
}
syms_of_eval (void)
{
DEFVAR_INT ("max-specpdl-size", max_specpdl_size,
- doc: /* *Limit on number of Lisp variable bindings and `unwind-protect's.
+ doc: /* Limit on number of Lisp variable bindings and `unwind-protect's.
If Lisp code tries to increase the total number past this amount,
an error is signaled.
You can safely use a value considerably larger than the default value,
Emacs could run out of memory trying to make the stack bigger. */);
DEFVAR_INT ("max-lisp-eval-depth", max_lisp_eval_depth,
- doc: /* *Limit on depth in `eval', `apply' and `funcall' before error.
+ doc: /* Limit on depth in `eval', `apply' and `funcall' before error.
This limit serves to catch infinite recursions for you before they cause
actual stack overflow in C, which would be fatal for Emacs.
DEFSYM (Qdebug, "debug");
DEFVAR_LISP ("debug-on-error", Vdebug_on_error,
- doc: /* *Non-nil means enter debugger if an error is signaled.
+ doc: /* Non-nil means enter debugger if an error is signaled.
Does not apply to errors handled by `condition-case' or those
matched by `debug-ignored-errors'.
If the value is a list, an error only means to enter the debugger
Vdebug_on_error = Qnil;
DEFVAR_LISP ("debug-ignored-errors", Vdebug_ignored_errors,
- doc: /* *List of errors for which the debugger should not be called.
+ doc: /* List of errors for which the debugger should not be called.
Each element may be a condition-name or a regexp that matches error messages.
If any element applies to a given error, that error skips the debugger
and just returns to top level.
Vdebug_ignored_errors = Qnil;
DEFVAR_BOOL ("debug-on-quit", debug_on_quit,
- doc: /* *Non-nil means enter debugger if quit is signaled (C-g, for example).
+ doc: /* Non-nil means enter debugger if quit is signaled (C-g, for example).
Does not apply if quit is handled by a `condition-case'. */);
debug_on_quit = 0;
Vsignal_hook_function = Qnil;
DEFVAR_LISP ("debug-on-signal", Vdebug_on_signal,
- doc: /* *Non-nil means call the debugger regardless of condition handlers.
+ doc: /* Non-nil means call the debugger regardless of condition handlers.
Note that `debug-on-error', `debug-on-quit' and friends
still determine whether to handle the particular condition. */);
Vdebug_on_signal = Qnil;
A value of `(t)' indicates an empty environment, otherwise it is an
alist of active lexical bindings. */);
Vinternal_interpreter_environment = Qnil;
- /* Don't export this variable to Elisp, so noone can mess with it
+ /* Don't export this variable to Elisp, so no one can mess with it
(Just imagine if someone makes it buffer-local). */
Funintern (Qinternal_interpreter_environment, Qnil);
staticpro (&Vsignaling_function);
Vsignaling_function = Qnil;
+ inhibit_lisp_code = Qnil;
+
defsubr (&Sor);
defsubr (&Sand);
defsubr (&Sif);
defsubr (&Sdefvar);
defsubr (&Sdefvaralias);
defsubr (&Sdefconst);
- defsubr (&Suser_variable_p);
defsubr (&Slet);
defsubr (&SletX);
defsubr (&Swhile);
HCoop / bpt / emacs.git / blobdiff