add missing files (part of #3171 fix)
[ghc.git] / rts / Globals.c
1 /* -----------------------------------------------------------------------------
2 *
3 * (c) The GHC Team, 1995-2009
4 *
5 * The RTS stores some "global" values on behalf of libraries, so that
6 * some libraries can ensure that certain top-level things are shared
7 * even when multiple versions of the library are loaded. e.g. see
8 * Data.Typeable and GHC.Conc.
9 *
10 * ---------------------------------------------------------------------------*/
11
12 #include "Rts.h"
13 #include "RtsGlobals.h"
14
15 static StgStablePtr typeableStore = 0;
16 static StgStablePtr signalHandlerStore = 0;
17
18 #ifdef THREADED_RTS
19 Mutex globalStoreLock;
20 #endif
21
22 void
23 initGlobalStore(void)
24 {
25 typeableStore = 0;
26 signalHandlerStore = 0;
27 #ifdef THREADED_RTS
28 initMutex(&globalStoreLock);
29 #endif
30 }
31
32 void
33 exitGlobalStore(void)
34 {
35 #ifdef THREADED_RTS
36 closeMutex(&globalStoreLock);
37 #endif
38 if(typeableStore!=0) {
39 freeStablePtr((StgStablePtr)typeableStore);
40 typeableStore=0;
41 }
42 if(signalHandlerStore!=0) {
43 freeStablePtr((StgStablePtr)signalHandlerStore);
44 signalHandlerStore=0;
45 }
46 }
47
48 StgStablePtr
49 getOrSetTypeableStore(StgStablePtr ptr)
50 {
51 StgStablePtr ret = typeableStore;
52 if(ret==0) {
53 #ifdef THREADED_RTS
54 ACQUIRE_LOCK(&globalStoreLock);
55 ret=typeableStore;
56 if(ret==0) {
57 #endif
58 typeableStore = ret = ptr;
59 #ifdef THREADED_RTS
60 }
61 RELEASE_LOCK(&globalStoreLock);
62 #endif
63 }
64 return ret;
65 }
66
67 StgStablePtr
68 getOrSetSignalHandlerStore(StgStablePtr ptr)
69 {
70 StgStablePtr ret = signalHandlerStore;
71 if(ret==0) {
72 #ifdef THREADED_RTS
73 ACQUIRE_LOCK(&globalStoreLock);
74 ret=signalHandlerStore;
75 if(ret==0) {
76 #endif
77 signalHandlerStore = ret = ptr;
78 #ifdef THREADED_RTS
79 }
80 RELEASE_LOCK(&globalStoreLock);
81 #endif
82 }
83 return ret;
84 }