/*
- smobs.hh -- declare smob related stuff.
+ This file is part of LilyPond, the GNU music typesetter.
- source file of the GNU LilyPond music typesetter
+ Copyright (C) 1999--2014 Han-Wen Nienhuys <hanwen@xs4all.nl>
- (c) 1999--2008 Han-Wen Nienhuys <hanwen@xs4all.nl>
+ LilyPond is free software: you can redistribute it and/or modify
+ it under the terms of the GNU General Public License as published by
+ the Free Software Foundation, either version 3 of the License, or
+ (at your option) any later version.
+
+ LilyPond is distributed in the hope that it will be useful,
+ but WITHOUT ANY WARRANTY; without even the implied warranty of
+ MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ GNU General Public License for more details.
+
+ You should have received a copy of the GNU General Public License
+ along with LilyPond. If not, see <http://www.gnu.org/licenses/>.
*/
#ifndef SMOBS_HH
Simple smobs are created by adding the
DECLARE_SIMPLE_SMOBS(Classname) to the declaration
+ A simple smob is only optionally under the reign of the GUILE
+ garbage collector: its usual life time is that of a normal C++
+ object. While a smobbed_copy () is fully under control of the
+ garbage collector and will have its mark_smob function called during
+ garbage collection, an automatic variable of this type will not have
+ mark_smob called, but rather have its memory image in the call stack
+ scanned for contained non-immediate SCM values. Anything requiring
+ more complex mark_smob behavior is not suitable for a simple smob.
+
+ When you create a smobbed_copy, the _copy_ is fully managed by the
+ GUILE memory system. As a corollary, multiple smobbed_copy calls
+ yield multiple GUILE objects generally not eq? to each other.
+
2. Complex smobs are objects that have an identity. These objects
carry this identity in the form of a self_scm () method, which is a
- SCM pointer to the object itself.
+ SCM pointer to the object itself. Complex smobs are always under
+ control of the GUILE memory system.
The constructor for a complex smob should have 3 steps:
- * initialize all SCM members to a non-immediate value (like SCM_EOL)
+ * initialize all SCM members to an immediate value (like SCM_EOL)
* call smobify_self ()
Complex_smob *p = new Complex_smob;
list = scm_cons (p->self_scm (), list);
- scm_gc_unprotect_object (p->self_scm ());
+ p->unprotect ();
+
+ Since unprotect returns the SCM object itself, this particular case
+ can be written as
+
+ Complex_smob *p = new Complex_smob;
+ list = scm_cons (p->unprotect (), list);
Complex smobs are made with DECLARE_SMOBS (Classname) in the class
declaration.
from file "ly-smobs.icc"
*/
-#define DECLARE_SIMPLE_SMOBS(CL) \
- public: \
- SCM smobbed_copy () const; \
+#define DECLARE_SIMPLE_SMOBS(CL) \
+ public: \
+ SCM smobbed_copy () const; \
DECLARE_BASE_SMOBS (CL)
-#define DECLARE_BASE_SMOBS(CL) \
- friend class Non_existent_class; \
- private: \
+#define DECLARE_BASE_SMOBS(CL) \
+ friend class Non_existent_class; \
+ private: \
static const char* smob_name_; \
- static scm_t_bits smob_tag_; \
- static SCM mark_smob (SCM); \
- static size_t free_smob (SCM s); \
- static int print_smob (SCM s, SCM p, scm_print_state*); \
- public: \
- static SCM equal_p (SCM a, SCM b); \
- static CL *unsmob (SCM s) __attribute__((pure)) \
- { \
- if (SCM_NIMP (s) && SCM_CELL_TYPE (s) == smob_tag_) \
- return (CL *) SCM_CELL_WORD_1 (s); \
- else \
- return 0; \
- } \
- static SCM smob_p (SCM); \
- static void init_smobs (); \
+ static scm_t_bits smob_tag_; \
+ static SCM mark_smob (SCM); \
+ static size_t free_smob (SCM s); \
+ static int print_smob (SCM s, SCM p, scm_print_state*); \
+ public: \
+ static SCM equal_p (SCM a, SCM b); \
+ static CL *unsmob (SCM s) __attribute__((pure)) \
+ { \
+ if (SCM_NIMP (s) && SCM_CELL_TYPE (s) == smob_tag_) \
+ return (CL *) SCM_CELL_WORD_1 (s); \
+ else \
+ return 0; \
+ } \
+ static SCM smob_p (SCM); \
+ static void init_smobs (); \
private:
-#define DECLARE_SMOBS(CL) \
- DECLARE_BASE_SMOBS (CL) \
- protected: \
- virtual ~CL (); \
- SCM unprotected_smobify_self (); \
- private: \
- void smobify_self (); \
- SCM self_scm_; \
- SCM protection_cons_; \
- public: \
- SCM unprotect (); \
- void protect (); \
- SCM self_scm () const { return self_scm_; } \
+#define DECLARE_SMOBS(CL) \
+ DECLARE_BASE_SMOBS (CL) \
+ protected: \
+ virtual ~CL (); \
+ SCM unprotected_smobify_self (); \
+ private: \
+ void smobify_self (); \
+ SCM self_scm_; \
+ SCM protection_cons_; \
+ public: \
+ SCM unprotect (); \
+ void protect (); \
+ SCM self_scm () const { return self_scm_; } \
private:
-#define DECLARE_UNSMOB(CL, name) \
- inline CL * \
- unsmob_ ## name (SCM s) \
- { \
- return CL::unsmob (s); \
+#define DECLARE_UNSMOB(CL, name) \
+ inline CL * \
+ unsmob_ ## name (SCM s) \
+ { \
+ return CL::unsmob (s); \
}
#define DECLARE_TYPE_P(CL) extern SCM CL ## _type_p_proc
void unprotect_smob (SCM smob, SCM *prot_cons);
extern bool parsed_objects_should_be_dead;
+class parsed_dead
+{
+ static vector<parsed_dead *> elements;
+ SCM data;
+ SCM readout_one ()
+ {
+ SCM res = data;
+ data = SCM_UNDEFINED;
+ return res;
+ }
+public:
+ parsed_dead () : data (SCM_UNDEFINED)
+ {
+ elements.push_back (this);
+ }
+ void checkin (SCM arg) { data = arg; }
+ static SCM readout ();
+};
#ifndef NDEBUG
-#define ASSERT_LIVE_IS_ALLOWED() \
- static bool passed_here_once;\
- if (parsed_objects_should_be_dead && !passed_here_once) { \
- ::programming_error (string ("Parsed object should be dead: ") + __PRETTY_FUNCTION__ ); \
- passed_here_once = true;\
- }
+#define ASSERT_LIVE_IS_ALLOWED(arg) \
+ do { \
+ static parsed_dead pass_here; \
+ if (parsed_objects_should_be_dead) \
+ pass_here.checkin (arg); \
+ } while (0)
#else
-#define ASSERT_LIVE_IS_ALLOWED()
+#define ASSERT_LIVE_IS_ALLOWED(arg) do { (void)(arg); } \
+ while (0)
#endif
#endif /* SMOBS_HH */
projects / lilypond.git / blobdiff