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(sxe_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);
84 if (data == OPAQUE_CLEAR)
85 memset(p->data, '\0', size);
86 else if (data == OPAQUE_UNINIT)
89 memcpy(p->data, data, size);
100 /* This will not work correctly for opaques with subobjects! */
102 static int equal_opaque(Lisp_Object obj1, Lisp_Object obj2, int depth)
105 return ((size = XOPAQUE_SIZE(obj1)) == XOPAQUE_SIZE(obj2) &&
106 !memcmp(XOPAQUE_DATA(obj1), XOPAQUE_DATA(obj2), size));
109 /* This will not work correctly for opaques with subobjects! */
111 static unsigned long hash_opaque(Lisp_Object obj, int depth)
113 if (XOPAQUE_SIZE(obj) == sizeof(unsigned long))
114 return *((unsigned long *)XOPAQUE_DATA(obj));
116 return memory_hash(XOPAQUE_DATA(obj), XOPAQUE_SIZE(obj));
119 static const struct lrecord_description opaque_description[] = {
123 DEFINE_LRECORD_SEQUENCE_IMPLEMENTATION("opaque", opaque,
125 equal_opaque, hash_opaque,
127 sizeof_opaque, Lisp_Opaque);
129 /* stuff to handle opaque pointers */
131 /* Should never, ever be called. (except by an external debugger) */
133 print_opaque_ptr(Lisp_Object obj, Lisp_Object printcharfun, int escapeflag)
135 const Lisp_Opaque_Ptr *p = XOPAQUE_PTR(obj);
137 write_fmt_string(printcharfun,
138 "#<INTERNAL OBJECT (SXEmacs bug?) "
139 "(opaque-ptr, adr=%p) %p>", p->ptr, p);
142 static int equal_opaque_ptr(Lisp_Object obj1, Lisp_Object obj2, int depth)
144 return (XOPAQUE_PTR(obj1)->ptr == XOPAQUE_PTR(obj2)->ptr);
147 static unsigned long hash_opaque_ptr(Lisp_Object obj, int depth)
149 return (unsigned long)XOPAQUE_PTR(obj)->ptr;
152 DEFINE_LRECORD_IMPLEMENTATION("opaque-ptr", opaque_ptr,
153 0, print_opaque_ptr, 0,
154 equal_opaque_ptr, hash_opaque_ptr, 0,
157 Lisp_Object make_opaque_ptr(void *val)
159 #if defined HAVE_BDWGC && defined EF_USE_BDWGC
160 Lisp_Object res = wrap_object(
161 alloc_lcrecord(sizeof(Lisp_Opaque_Ptr), &lrecord_opaque_ptr));
163 Lisp_Object res = allocate_managed_lcrecord(Vopaque_ptr_free_list);
166 set_opaque_ptr(res, val);
170 /* Be very very careful with this. Same admonitions as with
171 free_cons() apply. */
173 void free_opaque_ptr(Lisp_Object ptr)
175 #if defined HAVE_BDWGC && defined EF_USE_BDWGC
178 free_managed_lcrecord(Vopaque_ptr_free_list, ptr);
184 reinit_opaque_once_early(void)
186 #if !defined HAVE_BDWGC || !defined EF_USE_BDWGC
187 Vopaque_ptr_free_list =
188 make_lcrecord_list(sizeof(Lisp_Opaque_Ptr),
189 &lrecord_opaque_ptr);
190 staticpro_nodump(&Vopaque_ptr_free_list);
195 void init_opaque_once_early(void)
197 INIT_LRECORD_IMPLEMENTATION(opaque);
198 INIT_LRECORD_IMPLEMENTATION(opaque_ptr);
200 reinit_opaque_once_early();