1.0.5.21:
[sbcl.git] / src / runtime / dynbind.c
1 /*
2  * support for dynamic binding from C
3  */
4
5 /*
6  * This software is part of the SBCL system. See the README file for
7  * more information.
8  *
9  * This software is derived from the CMU CL system, which was
10  * written at Carnegie Mellon University and released into the
11  * public domain. The software is in the public domain and is
12  * provided with absolutely no warranty. See the COPYING and CREDITS
13  * files for more information.
14  */
15
16 #include "sbcl.h"
17 #include "runtime.h"
18 #include "globals.h"
19 #include "dynbind.h"
20 #include "thread.h"
21 #include "pseudo-atomic.h"
22 #include "genesis/symbol.h"
23 #include "genesis/binding.h"
24 #include "genesis/thread.h"
25 #include "genesis/static-symbols.h"
26
27 #if defined(BINDING_STACK_POINTER)
28 #define GetBSP() ((struct binding *)SymbolValue(BINDING_STACK_POINTER,thread))
29 #define SetBSP(value) SetSymbolValue(BINDING_STACK_POINTER, (lispobj)(value),thread)
30 #else
31 #define GetBSP() ((struct binding *)current_binding_stack_pointer)
32 #define SetBSP(value) (current_binding_stack_pointer=(lispobj *)(value))
33 #endif
34
35 void bind_variable(lispobj symbol, lispobj value, void *th)
36 {
37     struct binding *binding;
38     struct thread *thread=(struct thread *)th;
39     binding = GetBSP();
40     SetBSP(binding+1);
41 #ifdef LISP_FEATURE_SB_THREAD
42     {
43         struct symbol *sym=(struct symbol *)native_pointer(symbol);
44         if(!sym->tls_index) {
45             lispobj *tls_index_lock=
46                 &((struct symbol *)native_pointer(TLS_INDEX_LOCK))->value;
47             clear_pseudo_atomic_interrupted(th);
48             set_pseudo_atomic_atomic(th);
49             get_spinlock(tls_index_lock,(long)th);
50             if(!sym->tls_index) {
51                 sym->tls_index=SymbolValue(FREE_TLS_INDEX,0);
52                 SetSymbolValue(FREE_TLS_INDEX,
53                                make_fixnum(fixnum_value(sym->tls_index)+1),0);
54             }
55             release_spinlock(tls_index_lock);
56             clear_pseudo_atomic_atomic(th);
57             if (get_pseudo_atomic_interrupted(th))
58                 do_pending_interrupt();
59         }
60     }
61 #endif
62     binding->value = SymbolTlValue(symbol, thread);
63     binding->symbol = symbol;
64     SetTlSymbolValue(symbol, value, thread);
65 }
66
67 void
68 unbind(void *th)
69 {
70     struct thread *thread=(struct thread *)th;
71     struct binding *binding;
72     lispobj symbol;
73
74     binding = GetBSP() - 1;
75
76     symbol = binding->symbol;
77
78     SetTlSymbolValue(symbol, binding->value,thread);
79
80     binding->symbol = 0;
81
82     SetBSP(binding);
83 }
84
85 void
86 unbind_to_here(lispobj *bsp,void *th)
87 {
88     struct thread *thread=(struct thread *)th;
89     struct binding *target = (struct binding *)bsp;
90     struct binding *binding = GetBSP();
91     lispobj symbol;
92
93     while (target < binding) {
94         binding--;
95
96         symbol = binding->symbol;
97         if (symbol) {
98             SetTlSymbolValue(symbol, binding->value,thread);
99             binding->symbol = 0;
100         }
101     }
102     SetBSP(binding);
103 }