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