1 /* Opaque Lisp objects.
2 Copyright (C) 1993, 1994, 1995 Sun Microsystems, Inc.
3 Copyright (C) 1995, 1996 Ben Wing.
5 This file is part of SXEmacs
7 SXEmacs is free software: you can redistribute it and/or modify
8 it under the terms of the GNU General Public License as published by
9 the Free Software Foundation, either version 3 of the License, or
10 (at your option) any later version.
12 SXEmacs is distributed in the hope that it will be useful,
13 but WITHOUT ANY WARRANTY; without even the implied warranty of
14 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
15 GNU General Public License for more details.
17 You should have received a copy of the GNU General Public License
18 along with this program. If not, see <http://www.gnu.org/licenses/>. */
21 /* Synched up with: Not in FSF. */
23 /* Written by Ben Wing, October 1993. */
25 /* "Opaque" is used internally to hold keep track of allocated memory
26 so it gets GC'd properly, and to store arbitrary data in places
27 where a Lisp_Object is required and which may get GC'd. (e.g. as
28 the argument to record_unwind_protect()). Once created in C,
29 opaque objects cannot be resized.
31 OPAQUE OBJECTS SHOULD NEVER ESCAPE TO THE LISP LEVEL. Some code
32 depends on this. As such, opaque objects are a generalization
33 of the Qunbound marker.
40 #if !defined HAVE_BDWGC || !defined EF_USE_BDWGC
41 Lisp_Object Vopaque_ptr_free_list;
44 /* Should never, ever be called. (except by an external debugger) */
46 print_opaque(Lisp_Object obj, Lisp_Object printcharfun, int escapeflag)
48 const Lisp_Opaque *p = XOPAQUE(obj);
50 write_fmt_str(printcharfun,
51 "#<INTERNAL OBJECT (SXEmacs bug?) (opaque, size=%lu) 0x%lx>",
52 (long)(p->size), (unsigned long)p);
56 aligned_sizeof_opaque(size_t opaque_size)
57 __attribute__((always_inline));
59 aligned_sizeof_opaque(size_t opaque_size)
61 return ALIGN_SIZE(offsetof(Lisp_Opaque, data) + opaque_size,
62 ALIGNOF(max_align_t));
65 static size_t sizeof_opaque(const void *header)
67 return aligned_sizeof_opaque(((const Lisp_Opaque *)header)->size);
70 /* Return an opaque object of size SIZE.
71 If DATA is OPAQUE_CLEAR, the object's data is memset to '\0' bytes.
72 If DATA is OPAQUE_UNINIT, the object's data is uninitialized.
73 Else the object's data is initialized by copying from DATA. */
75 make_opaque(const void *data, size_t size)
77 Lisp_Opaque *p = (Lisp_Opaque *)
78 alloc_lcrecord(aligned_sizeof_opaque(size), &lrecord_opaque);
81 if (data == OPAQUE_CLEAR)
82 memset(p->data, '\0', size);
83 else if (data == OPAQUE_UNINIT)
86 memcpy(p->data, data, size);
95 /* This will not work correctly for opaques with subobjects! */
97 static int equal_opaque(Lisp_Object obj1, Lisp_Object obj2, int depth)
100 return ((size = XOPAQUE_SIZE(obj1)) == XOPAQUE_SIZE(obj2) &&
101 !memcmp(XOPAQUE_DATA(obj1), XOPAQUE_DATA(obj2), size));
104 /* This will not work correctly for opaques with subobjects! */
106 static unsigned long hash_opaque(Lisp_Object obj, int depth)
108 if (XOPAQUE_SIZE(obj) == sizeof(unsigned long))
109 return *((unsigned long *)XOPAQUE_DATA(obj));
111 return memory_hash(XOPAQUE_DATA(obj), XOPAQUE_SIZE(obj));
114 static const struct lrecord_description opaque_description[] = {
118 DEFINE_LRECORD_SEQUENCE_IMPLEMENTATION("opaque", opaque,
120 equal_opaque, hash_opaque,
122 sizeof_opaque, Lisp_Opaque);
124 /* stuff to handle opaque pointers */
126 /* Should never, ever be called. (except by an external debugger) */
128 print_opaque_ptr(Lisp_Object obj, Lisp_Object printcharfun, int escapeflag)
130 const Lisp_Opaque_Ptr *p = XOPAQUE_PTR(obj);
132 write_fmt_string(printcharfun,
133 "#<INTERNAL OBJECT (SXEmacs bug?) "
134 "(opaque-ptr, adr=%p) %p>", p->ptr, p);
137 static int equal_opaque_ptr(Lisp_Object obj1, Lisp_Object obj2, int depth)
139 return (XOPAQUE_PTR(obj1)->ptr == XOPAQUE_PTR(obj2)->ptr);
142 static unsigned long hash_opaque_ptr(Lisp_Object obj, int depth)
144 return (unsigned long)XOPAQUE_PTR(obj)->ptr;
147 DEFINE_LRECORD_IMPLEMENTATION("opaque-ptr", opaque_ptr,
148 0, print_opaque_ptr, 0,
149 equal_opaque_ptr, hash_opaque_ptr, 0,
152 Lisp_Object make_opaque_ptr(void *val)
154 #if defined HAVE_BDWGC && defined EF_USE_BDWGC
155 Lisp_Object res = wrap_object(
156 alloc_lcrecord(sizeof(Lisp_Opaque_Ptr), &lrecord_opaque_ptr));
158 Lisp_Object res = allocate_managed_lcrecord(Vopaque_ptr_free_list);
161 set_opaque_ptr(res, val);
165 /* Be very very careful with this. Same admonitions as with
166 free_cons() apply. */
168 void free_opaque_ptr(Lisp_Object ptr)
170 #if defined HAVE_BDWGC && defined EF_USE_BDWGC
173 free_managed_lcrecord(Vopaque_ptr_free_list, ptr);
179 reinit_opaque_once_early(void)
181 #if !defined HAVE_BDWGC || !defined EF_USE_BDWGC
182 Vopaque_ptr_free_list =
183 make_lcrecord_list(sizeof(Lisp_Opaque_Ptr),
184 &lrecord_opaque_ptr);
185 staticpro_nodump(&Vopaque_ptr_free_list);
190 void init_opaque_once_early(void)
192 INIT_LRECORD_IMPLEMENTATION(opaque);
193 INIT_LRECORD_IMPLEMENTATION(opaque_ptr);
195 reinit_opaque_once_early();