1 /*
2 MacOS.c
3
4 Some routines for the Macintosh OS port of the Hans-J. Boehm, Alan J. Demers
5 garbage collector.
6
7 <Revision History>
8
9 11/22/94 pcb StripAddress the temporary memory handle for 24-bit mode.
10 11/30/94 pcb Tracking all memory usage so we can deallocate it all at once.
11 02/10/96 pcb Added routine to perform a final collection when
12 unloading shared library.
13
14 by Patrick C. Beard.
15 */
16 /* Boehm, February 15, 1996 2:55 pm PST */
17
18 #include <Resources.h>
19 #include <Memory.h>
20 #include <LowMem.h>
21 #include <stdio.h>
22 #include <stdlib.h>
23 #include <string.h>
24
25 #include "gc.h"
26 #include "gc_priv.h"
27
28 // use 'CODE' resource 0 to get exact location of the beginning of global space.
29
30 typedef struct {
31 unsigned long aboveA5;
32 unsigned long belowA5;
33 unsigned long JTSize;
34 unsigned long JTOffset;
35 } *CodeZeroPtr, **CodeZeroHandle;
36
GC_MacGetDataStart()37 void* GC_MacGetDataStart()
38 {
39 CodeZeroHandle code0 = (CodeZeroHandle)GetResource('CODE', 0);
40 if (code0) {
41 long belowA5Size = (**code0).belowA5;
42 ReleaseResource((Handle)code0);
43 return (LMGetCurrentA5() - belowA5Size);
44 }
45 fprintf(stderr, "Couldn't load the jump table.");
46 exit(-1);
47 return 0;
48 }
49
50 /* track the use of temporary memory so it can be freed all at once. */
51
52 typedef struct TemporaryMemoryBlock TemporaryMemoryBlock, **TemporaryMemoryHandle;
53
54 struct TemporaryMemoryBlock {
55 TemporaryMemoryHandle nextBlock;
56 char data[];
57 };
58
59 static TemporaryMemoryHandle theTemporaryMemory = NULL;
60 static Boolean firstTime = true;
61
62 void GC_MacFreeTemporaryMemory(void);
63
GC_MacTemporaryNewPtr(size_t size,Boolean clearMemory)64 Ptr GC_MacTemporaryNewPtr(size_t size, Boolean clearMemory)
65 {
66 static Boolean firstTime = true;
67 OSErr result;
68 TemporaryMemoryHandle tempMemBlock;
69 Ptr tempPtr = nil;
70
71 tempMemBlock = (TemporaryMemoryHandle)TempNewHandle(size + sizeof(TemporaryMemoryBlock), &result);
72 if (tempMemBlock && result == noErr) {
73 HLockHi((Handle)tempMemBlock);
74 tempPtr = (**tempMemBlock).data;
75 if (clearMemory) memset(tempPtr, 0, size);
76 tempPtr = StripAddress(tempPtr);
77
78 // keep track of the allocated blocks.
79 (**tempMemBlock).nextBlock = theTemporaryMemory;
80 theTemporaryMemory = tempMemBlock;
81 }
82
83 # if !defined(SHARED_LIBRARY_BUILD)
84 // install an exit routine to clean up the memory used at the end.
85 if (firstTime) {
86 atexit(&GC_MacFreeTemporaryMemory);
87 firstTime = false;
88 }
89 # endif
90
91 return tempPtr;
92 }
93
94 extern word GC_fo_entries;
95
perform_final_collection()96 static void perform_final_collection()
97 {
98 unsigned i;
99 word last_fo_entries = 0;
100
101 /* adjust the stack bottom, because CFM calls us from another stack
102 location. */
103 GC_stackbottom = (ptr_t)&i;
104
105 /* try to collect and finalize everything in sight */
106 for (i = 0; i < 2 || GC_fo_entries < last_fo_entries; i++) {
107 last_fo_entries = GC_fo_entries;
108 GC_gcollect();
109 }
110 }
111
112
GC_MacFreeTemporaryMemory()113 void GC_MacFreeTemporaryMemory()
114 {
115 # if defined(SHARED_LIBRARY_BUILD)
116 /* if possible, collect all memory, and invoke all finalizers. */
117 perform_final_collection();
118 # endif
119
120 if (theTemporaryMemory != NULL) {
121 long totalMemoryUsed = 0;
122 TemporaryMemoryHandle tempMemBlock = theTemporaryMemory;
123 while (tempMemBlock != NULL) {
124 TemporaryMemoryHandle nextBlock = (**tempMemBlock).nextBlock;
125 totalMemoryUsed += GetHandleSize((Handle)tempMemBlock);
126 DisposeHandle((Handle)tempMemBlock);
127 tempMemBlock = nextBlock;
128 }
129 theTemporaryMemory = NULL;
130
131 # if !defined(SILENT) && !defined(SHARED_LIBRARY_BUILD)
132 fprintf(stdout, "[total memory used: %ld bytes.]\n",
133 totalMemoryUsed);
134 fprintf(stdout, "[total collections: %ld.]\n", GC_gc_no);
135 # endif
136 }
137 }
138
139 #if __option(far_data)
140
GC_MacGetDataEnd()141 void* GC_MacGetDataEnd()
142 {
143 CodeZeroHandle code0 = (CodeZeroHandle)GetResource('CODE', 0);
144 if (code0) {
145 long aboveA5Size = (**code0).aboveA5;
146 ReleaseResource((Handle)code0);
147 return (LMGetCurrentA5() + aboveA5Size);
148 }
149 fprintf(stderr, "Couldn't load the jump table.");
150 exit(-1);
151 return 0;
152 }
153
154 #endif /* __option(far_data) */
155