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 <stdio.h>
  17 #include <stdlib.h>
  18
  19 #include "sbcl.h"
  20 #include "runtime.h"
  21 #include "globals.h"
  22 #include "dynbind.h"
  23 #include "thread.h"
  24 #include "pseudo-atomic.h"
  25 #include "genesis/symbol.h"
  26 #include "genesis/binding.h"
  27 #include "genesis/thread.h"
  28 #include "genesis/static-symbols.h"
  29
  30 void bind_variable(lispobj symbol, lispobj value, void *th)
  31 {
  32     struct binding *binding;
  33     struct thread *thread=(struct thread *)th;
  34     binding = (struct binding *)get_binding_stack_pointer(thread);
  35     set_binding_stack_pointer(thread,binding+1);
  36 #ifdef LISP_FEATURE_SB_THREAD
  37     {
  38         struct symbol *sym=(struct symbol *)native_pointer(symbol);
  39         if(!sym->tls_index) {
  40             lispobj *tls_index_lock=
  41                 &((struct symbol *)native_pointer(TLS_INDEX_LOCK))->value;
  42             FSHOW_SIGNAL((stderr, "entering dynbind tls alloc\n"));
  43             set_pseudo_atomic_atomic(thread);
  44             get_spinlock(tls_index_lock,(long)th);
  45             if(!sym->tls_index) {
  46                 sym->tls_index=SymbolValue(FREE_TLS_INDEX,0);
  47                 SetSymbolValue(FREE_TLS_INDEX, sym->tls_index+N_WORD_BYTES, 0);
  48                 if((sym->tls_index)>=(TLS_SIZE << WORD_SHIFT)) {
  49                     lose("Thread local storage exhausted.");
  50                 }
  51             }
  52             release_spinlock(tls_index_lock);
  53             FSHOW_SIGNAL((stderr, "exiting dynbind tls alloc\n"));
  54             clear_pseudo_atomic_atomic(thread);
  55             if (get_pseudo_atomic_interrupted(thread))
  56                 do_pending_interrupt();
  57         }
  58     }
  59 #endif
  60     binding->value = SymbolTlValue(symbol, thread);
  61     binding->symbol = symbol;
  62     SetTlSymbolValue(symbol, value, thread);
  63 }
  64
  65 void
  66 unbind(void *th)
  67 {
  68     struct thread *thread=(struct thread *)th;
  69     struct binding *binding;
  70     lispobj symbol;
  71
  72     binding = ((struct binding *)get_binding_stack_pointer(thread)) - 1;
  73
  74     symbol = binding->symbol;
  75
  76     SetTlSymbolValue(symbol, binding->value,thread);
  77
  78     binding->symbol = 0;
  79     binding->value = 0;
  80
  81     set_binding_stack_pointer(thread,binding);
  82 }
  83
  84 void
  85 unbind_to_here(lispobj *bsp,void *th)
  86 {
  87     struct thread *thread=(struct thread *)th;
  88     struct binding *target = (struct binding *)bsp;
  89     struct binding *binding = (struct binding *)get_binding_stack_pointer(thread);
  90     lispobj symbol;
  91
  92     while (target < binding) {
  93         binding--;
  94
  95         symbol = binding->symbol;
  96         if (symbol) {
  97             if (symbol != UNBOUND_MARKER_WIDETAG) {
  98                 SetTlSymbolValue(symbol, binding->value,thread);
  99             }
 100             binding->symbol = 0;
 101             binding->value = 0;
 102         }
 103     }
 104     set_binding_stack_pointer(thread,binding);
 105 }