xref: /plan9/sys/src/cmd/gs/src/gsstype.h (revision 593dc095aefb2a85c828727bbfa9da139a49bdf4)
1 /* Copyright (C) 1999 Aladdin Enterprises.  All rights reserved.
2 
3   This software is provided AS-IS with no warranty, either express or
4   implied.
5 
6   This software is distributed under license and may not be copied,
7   modified or distributed except as expressly authorized under the terms
8   of the license contained in the file LICENSE in this distribution.
9 
10   For more information about licensing, please refer to
11   http://www.ghostscript.com/licensing/. For information on
12   commercial licensing, go to http://www.artifex.com/licensing/ or
13   contact Artifex Software, Inc., 101 Lucas Valley Road #110,
14   San Rafael, CA  94903, U.S.A., +1(415)492-9861.
15 */
16 
17 /* $Id: gsstype.h,v 1.6 2004/08/04 19:36:12 stefan Exp $ */
18 /* Definition of structure type descriptors and extern_st */
19 
20 #ifndef gsstype_INCLUDED
21 #  define gsstype_INCLUDED
22 
23 /* Define an opaque type for the garbage collector state. */
24 typedef struct gc_state_s gc_state_t;
25 
26 /*
27  * Define the structure used to return an enumerated pointer.  Ordinary
28  * object pointers use only the ptr element; strings also use size.
29  */
30 typedef struct enum_ptr_s {
31     const void *ptr;
32     uint size;
33 } enum_ptr_t;
34 
35 /*
36  * The first argument of enum_ptrs procedures formerly was not const *, and
37  * EV_CONST was defined as empty.  Unfortunately, changing EV_CONST to const
38  * produced many compiler warnings from places that cast this argument to a
39  * non-const non-void pointer type.
40  */
41 #define EV_CONST const
42 
43 /* Define the procedures for structure types. */
44 
45 		/* Clear the marks of a structure. */
46 
47 #define struct_proc_clear_marks(proc)\
48   void proc(const gs_memory_t *cmem, void /*obj_header_t*/ *pre, uint size,\
49     const gs_memory_struct_type_t *pstype)
50 
51 		/* Enumerate the pointers in a structure. */
52 
53 #define struct_proc_enum_ptrs(proc)\
54   gs_ptr_type_t proc(const gs_memory_t *mem, EV_CONST void /*obj_header_t*/ *ptr, uint size,\
55     int index, enum_ptr_t *pep, const gs_memory_struct_type_t *pstype,\
56     gc_state_t *gcst)
57 
58 		/* Relocate all the pointers in this structure. */
59 
60 #define struct_proc_reloc_ptrs(proc)\
61   void proc(void /*obj_header_t*/ *ptr, uint size,\
62     const gs_memory_struct_type_t *pstype, gc_state_t *gcst)
63 
64 		/*
65 		 * Finalize this structure just before freeing it.
66 		 * Finalization procedures must not allocate or resize
67 		 * any objects in any space managed by the allocator,
68 		 * and must not assume that any objects in such spaces
69 		 * referenced by this structure still exist.  However,
70 		 * finalization procedures may free such objects, and
71 		 * may allocate, free, and reference objects allocated
72 		 * in other ways, such as objects allocated with malloc
73 		 * by libraries.
74 		 */
75 
76 #define struct_proc_finalize(proc)\
77   void proc(void /*obj_header_t*/ *ptr)
78 
79 /*
80  * A descriptor for an object (structure) type.
81  */
82 typedef struct struct_shared_procs_s struct_shared_procs_t;
83 
84 struct gs_memory_struct_type_s {
85 	uint ssize;
86 	struct_name_t sname;
87 
88 	/* ------ Procedures shared among many structure types. ------ */
89 	/* Note that this pointer is usually 0. */
90 
91 	const struct_shared_procs_t *shared;
92 
93 	/* ------ Procedures specific to this structure type. ------ */
94 
95 	struct_proc_clear_marks((*clear_marks));
96 	struct_proc_enum_ptrs((*enum_ptrs));
97 	struct_proc_reloc_ptrs((*reloc_ptrs));
98 	struct_proc_finalize((*finalize));
99 
100 	/* A pointer to additional data for the above procedures. */
101 
102 	const void *proc_data;
103 };
104 
105 /*
106  * Because of bugs in some compilers' bookkeeping for undefined structure
107  * types, any file that uses extern_st must include this file.
108  * (If it weren't for these bugs, the definition of extern_st could
109  * go in gsmemory.h.)
110  */
111 #define extern_st(st) extern const gs_memory_struct_type_t st
112 
113 #endif /* gsstype_INCLUDED */
114