scope.c

   1 /*
   2  * Symbol scoping.
   3  *
   4  * This is pretty trivial.
   5  *
   6  * Copyright (C) 2003 Transmeta Corp.
   7  *               2003 Linus Torvalds
   8  *
   9  *  Licensed under the Open Software License version 1.1
  10  */
  11 #include <stdlib.h>
  12 #include <string.h>
  13
  14 #include "lib.h"
  15 #include "symbol.h"
  16 #include "scope.h"
  17
  18 static struct scope toplevel_scope = { .next = &toplevel_scope };
  19
  20 struct scope    *block_scope = &toplevel_scope,
  21                 *function_scope = &toplevel_scope,
  22                 *file_scope = &toplevel_scope;
  23
  24 void bind_scope(struct symbol *sym, struct scope *scope)
  25 {
  26         sym->scope = scope;
  27         add_symbol(&scope->symbols, sym);
  28 }
  29
  30 static void start_scope(struct scope **s)
  31 {
  32         struct scope *scope = __alloc_scope(0);
  33         memset(scope, 0, sizeof(*scope));
  34         scope->next = *s;
  35         *s = scope;
  36 }
  37
  38 void start_symbol_scope(void)
  39 {
  40         start_scope(&block_scope);
  41 }
  42
  43 void start_function_scope(void)
  44 {
  45         start_scope(&function_scope);
  46         start_scope(&block_scope);
  47 }
  48
  49 static void remove_symbol_scope(struct symbol *sym)
  50 {
  51         struct symbol **ptr = sym->id_list;
  52
  53         while (*ptr != sym)
  54                 ptr = &(*ptr)->next_id;
  55         *ptr = sym->next_id;
  56 }
  57
  58 static void end_scope(struct scope **s)
  59 {
  60         struct scope *scope = *s;
  61         struct symbol_list *symbols = scope->symbols;
  62         struct symbol *sym;
  63
  64         *s = scope->next;
  65         scope->symbols = NULL;
  66         FOR_EACH_PTR(symbols, sym) {
  67                 remove_symbol_scope(sym);
  68         } END_FOR_EACH_PTR;
  69 }
  70
  71 void end_symbol_scope(void)
  72 {
  73         end_scope(&block_scope);
  74 }
  75
  76 void end_function_scope(void)
  77 {
  78         end_scope(&block_scope);
  79         end_scope(&function_scope);
  80 }