cdecl.c

guide and some example with visualC++

static void f_ext_decl(token_t * e1)
{
    switch (EiC_lexan()) {
      DECL:
	decl(e1, token->Tok);
	ff_ext_decl(e1);
	break;
      case ';':
	break;
      default:
	EiC_error("Declaration error");
	EiC_match(';', " ; ");
    }
}

token_t *EiC_genTemporay(type_expr *type, int level)
{
    token_t *e1 = xcalloc(sizeof(token_t),1);
    extern symentry_t * EiC_nxtTemp(int obj, int level);
    symentry_t * sym;

    sym = EiC_nxtTemp(ID,level);
    EiC_inittoken(e1);
    SetTemp(type);
    e1->Type = EiC_copytype(type);
    e1->Val.sym =  sym;
    e1->Tab = sym->nspace;
    new_var(e1);
    e1->Val = sym->val;
    return e1;

    
}

static void do_Gotos(code_t *c)
{
    if(c->gotos) {
	Label_t *go, *lab;
	go = c->gotos;
	while(go) {
	    lab = c->labels;
	    while(lab && strcmp(lab->name,go->name) != 0)
		lab = lab->nxt;
	    if(lab) 
		ivalcode(c,go->loc) = lab->loc - go->loc;
	    else
		EiC_error("Missing label `%s' defined at line %d",go->name,instline(c,go->loc));
	    go = go->nxt;
	}
    }
}
    
static void ff_ext_decl(token_t * e1)
{

    extern void EiC_UpdateEntry(symentry_t * sym);

    int t;
    switch (EiC_lexan()) {
      case '{': /* handle funtion definition */

	if (EiC_S_LEVEL > 1) {
	  EiC_error("Illegal function definition in %s",EiC_RETURNEXPR->Sym->id);
	  break; 
	}
	new_var(e1);

	if((t = EiC_gotMissingNames(EiC_getInf(e1->Type))))
            EiC_error("Missing name for Paramater %d",t);
	
	if(EiC_ErrorRecover) /* force recovery */
	    EiC_ErrorRecover = 0;
	
	if((t = EiC_gettype(e1->Type)) == t_funcdec || t == t_func) {
	    token_t e2;
	    code_t *code;

	    EiC_inittoken(&e2);

	    if(EiC_HasHiddenParm(e1->Type)) 
		EiC_addoffsettolevel(stand_tab, EiC_S_LEVEL+1,2);
	    else
		EiC_addoffsettolevel(stand_tab, EiC_S_LEVEL+1,1);

	    retractlexan();
	    if (e1->Sym->ass) {
		EiC_warningerror("Function Re-definition of %s",e1->Sym->id);
		EiC_freeFuncComments(EiC_getInf(e1->Type));
       	    }

	    /* Update declaration to definition. */
	    EiC_exchtype(t_func, e1->Type);
	    EiC_INFUNC = 1;
	    EiC_RETURNON++;
	    EiC_RETURNEXPR = e1;
	    EiC_stmt(&e2);

	    EiC_RETURNON--;
	    EiC_reset_env_pointers(e1, LSP);

	    do_Gotos(&e2.Code);
	     /* remove reducear,  if present */
	    if(e2.Code.nextinst != 0) { 
		if (e2.Code.inst[e2.Code.nextinst - 1].opcode ==
		    reducear)
		    e2.Code.nextinst--;
		    addreturn(e1,&e2.Code);
	    } else {
		EiC_warningerror("Empty function definition");
		EiC_generate(&e2.Code, eicreturn, &e2.Val, 0);    
	    }
	    if(!EiC_ParseError) {
		if(e1->Sym->ass)
		    EiC_killcode(e1->Sym);
		code = (code_t *) xcalloc(1, sizeof(code_t));
		e1->Sym->ass = 1;
		*code = e2.Code;
		EiC_ENV->AR[e1->Sym->val.ival].v.p.p = code;
		codeName(code) = CurrentFileName();
	    } else {
		void EiC_cleancode(code_t *);
		EiC_cleancode(&e2.Code);
		EiC_freecode(&e2.Code);
	    }
		
	    EiC_freetype(e2.Type);
	    e1->Type = NULL;	/* hide new type */
	    EiC_INFUNC = 0;
	} else {
	    e1->Type = NULL;
	    retractlexan();
	}
	break;
      default:
	if (e1->Val.sym) {
	  
 	  if(token->Tok == '@') {   /* watch for reference declaration */
	      e1->Type = EiC_revtype(e1->Type);
	      e1->Type = EiC_addtype(t_ref,e1->Type);
	      EiC_setAsBaseType(e1->Type);
	  }
 	  new_var(e1);
	}

	EiC_remlevel(EiC_S_LEVEL + 1);
	if(token->Tok == ASS) {
	    initialiser(e1);
	    EiC_lexan();
	} else if(token->Tok == '@') {
	  handle_address_operator(e1);
	  EiC_lexan();
	}
	fff_ext_decl(e1);
    }
}

static void fff_ext_decl(token_t * e1)
{
    if (RESET) {
	EiC_reset_env_pointers(e1, LSP);
	RESET--;
    }
    setBoundaryLimits(e1);

    if(EiC_gettype(e1->Type) == t_array &&
       !EiC_get_sizeof(nextType(e1->Type)))
	EiC_error("Ilegal size specified for %s", e1->Sym->id);


    if (token->Tok == ',') {
	
	init_decl_list(e1);
	e1->Type = NULL;	/* hide new type */
	EiC_match(';', " ;");
    } else {
	retractlexan();
	semi_colon(e1);
    }




}

static void semi_colon(token_t * e1)
{
    e1->Type = NULL;	/* hide new type */
    if(!EiC_match(';', ";"))
	retractlexan();
}

static void decl_spec(token_t * e1)
{
    int sclass = 0;
    void specifier(token_t *e1, int,int *sclass);

    switch (token->Tok) {
      STORECLASS:
      TYPEQUAL:
      TYPESPEC:
	specifier(e1, token->Tok,&sclass);
	if ((sclass == c_auto || sclass == c_register)
	    && !(EiC_INFUNC || EiC_S_LEVEL > 1))
	    EiC_error("Illegal storage class usage");
	else if(INPARMLIST && sclass && sclass != c_register)
	    EiC_error("Illegal storage class for parameter %s",EiC_LEXEM);
	else
	    e1->Sclass = sclass;
	EiC_setAsBaseType(e1->Type);
	/* default:
	retractlexan();
	*/
    }
}

static void specifier(token_t *e1, int t,int *sclass)
{
    /* This function was modelled from lcc32's
     * specifier function
     */

    int cls, cons, sign, size, type, vol,ty;
    cls = ty = vol = cons = sign = size = type=0;

    if(sclass == NULL)
      cls = c_auto;
        
    while(1){
      int *p, tt = t;
      switch (t) {
      case autosym:     tt = c_auto;     p = &cls; break;  
      case externsym:   tt = c_extern;   p = &cls; break;  
      case registersym: tt = c_register; p = &cls; break;  
      case staticsym:   tt = c_static;   p = &cls; break;  
      case typedefsym:  tt = c_typedef;  p = &cls; break;  
      case constsym:   p = &cons;       break;
      case volatilesym:p = &vol;        break;
      case signedsym:
      case unsignedsym:p = &sign;       break;
      case longsym:
	if(size == longsym) {
	  size = 0;
	  tt = longsym+longsym;
	}

      case shortsym:   p = &size;      break;
      case voidsym:    ty = t_void;   p = &type;   break;
      case charsym:    ty = t_char;   p = &type;   break;
      case intsym:     ty = t_int;    p = &type;   break;
      case floatsym:   ty = t_float;  p = &type;   break;
      case doublesym:  ty = t_double; p = &type;   break;
      case enumsym:     
      case structsym:
      case unionsym:   {
	token_t e2;
	p = &type;
	EiC_inittoken(&e2);
	if (t == enumsym)
	     enum_spec(&e2);
	     else
	     st_un_spec(&e2, t);
	/*
	 *  test tag name.
	 */
	if (e2.Val.sym) {
	  e1->Type = EiC_copytype(e2.Type);
	  e1->Tab = stand_tab;
	  if(INSTUN)
	    addst_un_tag(e2.Val.sym);
	} else {
	  int sclass = e1->Sclass;
	  *e1 = e2;
	  e1->Sclass = sclass;
	  if(t == enumsym)
	    cast_t_enum(e1);
	}
      }
      break;
      case TYPENAME:
	if(type == 0 && p != &sign && p != &size) {
	  e1->Type = EiC_copytype(token->Val.sym->type);
	  p = &type;
	} else { /* allow for masking and redeclarations */
#if 1
	  if(checklevel(e1,token->Val.sym,EiC_S_LEVEL) || 
	        cls == c_typedef) {
	    token->Tok = ID;
	    retractlexan();
	  } else 
	    EiC_error("Illegal use of typedef %s",token->Val.sym->id); 
	  p = NULL;
#else
	  token->Tok = ID;
	  retractlexan();
	  p = NULL;
#endif 
	}
	break;
	    
      default:
	retractlexan();
	p = NULL;
      }
      if (p == NULL)
	break;
      if (*p)
	EiC_error("invalid specification");
      *p = tt;
      t = EiC_lexan();
    }
    if(sclass)
	*sclass = cls;
    if(type == 0) {
	type = intsym;
	ty = t_int;
    }
    if ((size == shortsym && type != intsym)
        ||  (size == longsym  && type != intsym && type != doublesym)
        ||  (sign && type != intsym && type != charsym))
                EiC_error("invalid type specification");
    if (type == charsym && sign)
	ty = sign == unsignedsym ? t_uchar : t_char;
    else if (size == shortsym)
	ty = sign == unsignedsym ? t_ushort : t_short;
    else if (size == longsym && type == doublesym)
	ty = t_double;
    else if (size == longsym+longsym) { 

#ifndef NO_LONG_LONG
      ty = t_llong;
#else
      ty = sign == unsignedsym ? t_ulong : t_long;
#endif

    } else if (size == longsym)
	ty = sign == unsignedsym ? t_ulong : t_long;
    else if (sign == unsignedsym && type == intsym)
	ty = t_uint;

      
    if(ty)
	e1->Type = EiC_addtype(ty,e1->Type);

    if (cons == constsym) {
	if(INPARMLIST || EiC_INFUNC)  /* */
	    setConstp(e1->Type);
	else 	    
	    setConst(e1->Type);
	/*
	if(EiC_INFUNC && !INPARMLIST && sclass) 
	*sclass = c_static;
	*/
    }

	
    /* ignore volatile for now;
       if (vol  == VOLATILE)
       ty = qual(VOLATILE, ty);
       */
}

static void init_decl_list(token_t * e1)
{
    token_t e2;
    do {
	EiC_inittoken(&e2);
	
	switch (EiC_lexan()) {
	  DECL:
	    e2.Type = EiC_copyBaseType(e1->Type);
	    e2.Sclass = e1->Sclass;
	    
	    init_decl(&e2, token->Tok);
	    if (RESET) {
		EiC_reset_env_pointers(&e2, LSP);
		RESET--;
	    }
	    EiC_concode(&e1->Code, &e2.Code);
	    EiC_remlevel(EiC_S_LEVEL+1);
	    setBoundaryLimits(&e2);
	    break;
	    
	  default:
	    EiC_error("Init decl list error");
	}

	if(EiC_gettype(e2.Type) == t_array &&
	   !EiC_get_sizeof(nextType(e2.Type)))
	    EiC_error("Ilegal size specified for %s", e2.Sym->id);

    } while (EiC_lexan() == ',');
    retractlexan();
}

static void init_decl(token_t * e1, int ty)
{
    int t;
    decl(e1, ty);
#if 1
 
     t = EiC_lexan();
 
     if(t == '@') {   /* watch for reference declaration */
       e1->Type = EiC_addtype(t_ref,e1->Type);
       EiC_setAsBaseType(e1->Type);
     }

#endif

    new_var(e1);
 
#if 1

    if(t == ASS)
      initialiser(e1);
    else if(t == '@') { 
      handle_address_operator(e1);
    } else
       retractlexan();

#else


   if (EiC_lexan() == ASS) {
	initialiser(e1);
    } else
	retractlexan();

#endif
}

static void initglobal(type_expr * type, void **addr,int lev);
static void initstruct(type_expr * type, void **addr,int lev);
static void do_struct(type_expr *type, void **addr,int lev);
static int initarray(type_expr * type, void ** addr, int size, int lev);
static void assign_var(type_expr *type, void *addr,int allow);
static int do_array(type_expr *type, void ** addr, int size, int lev, int inc);

static void structUnionCode(token_t * e1, token_t *e2)
{
    val_t v;
    v = e1->Val;
    e1->Val = e1->Sym->val;
    EiC_output(e1);
    e1->Val = v;
    v.ival = 1;
    EiC_generate(&e1->Code, bump, &v, 0);
    v.ival = EiC_get_sizeof(e2->Type);
    EiC_generate(&e2->Code,refmem,&v,0);
}

static token_t * E1;
static void initialiser(token_t * e1)
{
    int t;
    int peek = EiC_lexan();
    retractlexan();
    
    if(EiC_GI(e1) == 0) {  /* global or static local variable */
	E1 = e1;
	if ((t =EiC_gettype(e1->Type)) <= t_pointer) { /* get scalars */
	    int v = 1;
	    if(e1->Sclass & c_static) /* catch statics */
		v = 0;
	    if(!isconst(e1->Type))  		
		assign_var(e1->Type,&EiC_ENV->AR[e1->Sym->val.ival].v,v);
	    else {
		assign_var(e1->Type,&e1->Sym->val,v);
		switch(EiC_gettype(e1->Type)) {
		case t_char:   e1->Sym->val.ival = e1->Sym->val.cval;break;
		case t_uchar:  e1->Sym->val.ival = e1->Sym->val.ucval;break;
		case t_short:  e1->Sym->val.ival = e1->Sym->val.sval;break;
		case t_ushort: e1->Sym->val.ival = e1->Sym->val.usval;break;
		case t_float:   e1->Sym->val.dval = e1->Sym->val.fval;break;
		}
	    }
	} else {
 	    if(!isconst(e1->Type))
		initglobal(e1->Type,&EiC_ENV->AR[e1->Sym->val.ival].v.p.p,0);
	    else {
		initglobal(e1->Type,&e1->Sym->val.p.p,0);
	    }
	}
    } else {	
	if ((t =EiC_gettype(e1->Type)) <= t_pointer /* local scalar types */
	    || ((t == t_struct || t==t_union) && peek != '{')  
	    ) { 
	    if(isconst(e1->Type)) 
		assign_var(e1->Type,&e1->Sym->val,0);
	    else {
		token_t e2;
		val_t h; 
		EiC_inittoken(&e2);
		EiC_assign_expr(&e2);
		if (isconst(e2.Type)) {
		    EiC_castconst(&e2,e1,0);	    
		    h = e1->Val;
		    e1->Val = e1->Sym->val;
		    EiC_generate(&e1->Code,pushval,&e2.Val,0);
		    EiC_do_stooutput(e1);
		    e1->Val = h;
		    EiC_freetoken(&e2);
		} else {
		    EiC_output(&e2);
		    EiC_castvar(&e2,e1,0);
		    if (t == t_struct || t == t_union)
			structUnionCode(e1,&e2);
		    EiC_concode(&e1->Code,&e2.Code);
		    h = e1->Val;
		    e1->Val = e1->Sym->val;
		    EiC_do_stooutput(e1);
		    e1->Val = h;
		}
		EiC_freetoken(&e2);
	    }
	} else if(EiC_INFUNC) {
	    /* code for initialising automatic aggregate types */
	    extern unsigned EiC_ASPOT;
	    int s2, s1 = EiC_get_sizeof(e1->Type);
	    val_t v;
	    E1 = e1;
	    
	    if(s1)
		v.p.p = xcalloc(1,s1);
	    else
		v.p.p = NULL;
	    initglobal(e1->Type,&v.p.p,0);
	    if((s2 = EiC_get_sizeof(e1->Type)) > s1)
		EiC_ASPOT += s2 - s1;
	    EiC_add_func_initialiser(EiC_getInf(EiC_RETURNEXPR->Type),v.p.p);
	    EiC_generate(&e1->Code,minit,&v,s2);
	} else	
	    EiC_error("Initialisation not "
		  "supported for non scalar local types");	
    }
}

static void initglobal(type_expr * type, void **addr, int lev)
{
    switch(EiC_gettype(type)) {
      case t_array:
	initarray(type,addr,0,lev); break;
      case t_struct:
	initstruct(type,addr,lev); break;
      case t_union: