/* GNU Objective C Runtime message lookup    Copyright (C) 1993, 1995 Free Software Foundation, Inc.   Contributed by Kresten Krab ThorupThis file is part of GNU CC.GNU CC is free software; you can redistribute it and/or modify it under theterms of the GNU General Public License as published by the Free SoftwareFoundation; either version 2, or (at your option) any later version.GNU CC is distributed in the hope that it will be useful, but WITHOUT ANYWARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESSFOR A PARTICULAR PURPOSE.  See the GNU General Public License for moredetails.You should have received a copy of the GNU General Public License along withGNU CC; see the file COPYING.  If not, write to the Free SoftwareFoundation, 59 Temple Place - Suite 330,Boston, MA 02111-1307, USA.  *//* As a special exception, if you link this library with files compiled with   GCC to produce an executable, this does not cause the resulting executable   to be covered by the GNU General Public License. This exception does not   however invalidate any other reasons why the executable file might be   covered by the GNU General Public License.  */#include "../tconfig.h"#include "runtime.h"#include "sarray.h"#include "encoding.h"/* this is how we hack STRUCT_VALUE to be 1 or 0 */#define gen_rtx(args...) 1#define rtx int#if STRUCT_VALUE == 0#define INVISIBLE_STRUCT_RETURN 1#else#define INVISIBLE_STRUCT_RETURN 0#endif/* The uninstalled dispatch table */struct sarray* __objc_uninstalled_dtable = 0;/* Send +initialize to class */static void __objc_send_initialize(Class);static void __objc_install_dispatch_table_for_class (Class);/* Forward declare some functions */static void __objc_init_install_dtable(id, SEL);static id __objc_word_forward(id, SEL, ...);typedef struct { id many[8]; } __big;#if INVISIBLE_STRUCT_RETURN static __big #elsestatic id#endif__objc_block_forward(id, SEL, ...);static Method_t search_for_method_in_hierarchy (Class class, SEL sel);static Method_t search_for_method_in_list(MethodList_t list, SEL op);id nil_method(id, SEL, ...);idnil_method(id receiver, SEL op, ...){  return receiver;}/* Given a class and selector, return the selector's implementation.  */__inline__IMPget_imp (Class class, SEL sel){  IMP impl;  void* res = sarray_get (class->dtable, (size_t) sel->sel_id);  if(res == __objc_init_install_dtable)    {      __objc_install_dispatch_table_for_class (class);      res = sarray_get (class->dtable, (size_t) sel->sel_id);    }  if (res == 0)    {      const char *t = sel->sel_types;      if (t && (*t == '[' || *t == '(' || *t == '{'))	res = (IMP)__objc_block_forward;      else	res = (IMP)__objc_word_forward;    }  return res;}__inline__ BOOL__objc_responds_to (id object, SEL sel){  void* res = sarray_get (object->class_pointer->dtable, (size_t) sel->sel_id);  if(res == __objc_init_install_dtable)    {      __objc_install_dispatch_table_for_class (object->class_pointer);      res = sarray_get (object->class_pointer->dtable, (size_t) sel->sel_id);    }  return (res != 0);}/* This is the lookup function.  All entries in the table are either a    valid method *or* one of `__objc_missing_method' which calls   forward:: etc, or `__objc_init_install_dtable' which installs the   real dtable */__inline__ IMPobjc_msg_lookup(id receiver, SEL op){  IMP result;  if(receiver)    {      result = sarray_get(receiver->class_pointer->dtable, (sidx)op->sel_id);      if (result == 0)	{	  const char *t = op->sel_types;	  if (t && (*t == '[' || *t == '(' || *t == '{'))	    result = (IMP)__objc_block_forward;	  else	    result = (IMP)__objc_word_forward;	}      return result;    }  else    return nil_method;}IMPobjc_msg_lookup_super (Super_t super, SEL sel){  if (super->self)    return get_imp (super->class, sel);  else    return nil_method;}int method_get_sizeof_arguments (Method*);retval_tobjc_msg_sendv(id object, SEL op, arglist_t arg_frame){  Method* m = class_get_instance_method(object->class_pointer, op);  const char *type;  *((id*)method_get_first_argument (m, arg_frame, &type)) = object;  *((SEL*)method_get_next_argument (arg_frame, &type)) = op;  return __builtin_apply((apply_t)m->method_imp, 			 arg_frame,			 method_get_sizeof_arguments (m));}void __objc_init_dispatch_tables(){  __objc_uninstalled_dtable    = sarray_new(200, __objc_init_install_dtable);}/* This one is a bit hairy.  This function is installed in the    premature dispatch table, and thus called once for each class,   namely when the very first message is send to it.  */static void __objc_init_install_dtable(id receiver, SEL op){  __label__ already_initialized;  IMP imp;  void* args;  void* result;  /* This may happen, if the programmer has taken the address of a      method before the dtable was initialized... too bad for him! */  if(receiver->class_pointer->dtable != __objc_uninstalled_dtable)    goto already_initialized;  if(CLS_ISCLASS(receiver->class_pointer))    {      /* receiver is an ordinary object */      assert(CLS_ISCLASS(receiver->class_pointer));      /* install instance methods table */      __objc_install_dispatch_table_for_class (receiver->class_pointer);      /* call +initialize -- this will in turn install the factory 	 dispatch table if not already done :-) */      __objc_send_initialize(receiver->class_pointer);    }  else    {      /* receiver is a class object */      assert(CLS_ISCLASS((Class)receiver));      assert(CLS_ISMETA(receiver->class_pointer));      /* Install real dtable for factory methods */      __objc_install_dispatch_table_for_class (receiver->class_pointer);      if (strcmp (sel_get_name (op), "initialize"))	__objc_send_initialize((Class)receiver);      else	CLS_SETINITIALIZED((Class)receiver);    }already_initialized:    /* Get real method for this in newly installed dtable */  imp = get_imp(receiver->class_pointer, op);  args = __builtin_apply_args();  result = __builtin_apply((apply_t)imp, args, 96);  if (result)    __builtin_return (result);  else    return;  }/* Install dummy table for class which causes the first message to   that class (or instances hereof) to be initialized properly */void __objc_install_premature_dtable(Class class){  assert(__objc_uninstalled_dtable);  class->dtable = __objc_uninstalled_dtable;}   /* Send +initialize to class if not already done */static void __objc_send_initialize(Class class){  /* This *must* be a class object */  assert(CLS_ISCLASS(class));  assert(!CLS_ISMETA(class));  if (!CLS_ISINITIALIZED(class))    {      CLS_SETINITIALIZED(class);      CLS_SETINITIALIZED(class->class_pointer);            if(class->super_class)	__objc_send_initialize(class->super_class);      {	SEL 	op = sel_register_name ("initialize");	Class	tmpclass = class;	IMP	imp = 0;	while (!imp && tmpclass) {	  MethodList_t method_list = tmpclass->class_pointer->methods;	  while(!imp && method_list) {	    int i;	    Method_t method;	    for (i=0;i<method_list->method_count;i++) {	      method = &(method_list->method_list[i]);	      if (method->method_name->sel_id == op->sel_id) {	        imp = method->method_imp;	        break;	      }	    }	    method_list = method_list->method_next;	  }	  tmpclass = tmpclass->super_class;	}	if (imp)	    (*imp)((id)class, op);		      }    }}  static void__objc_install_dispatch_table_for_class (Class class){  Class super;  MethodList_t mlist;  int counter;  /* If the class has not yet had it's class links resolved, we must      re-compute all class links */  if(!CLS_ISRESOLV(class))    __objc_resolve_class_links();  super = class->super_class;  if (super != 0 && (super->dtable == __objc_uninstalled_dtable))    __objc_install_dispatch_table_for_class (super);  /* Allocate dtable if necessary */  if (super == 0)    {      class->dtable = sarray_new (__objc_selector_max_index, 0);    }  else    class->dtable = sarray_lazy_copy (super->dtable);  for (mlist = class->methods; mlist; mlist = mlist->method_next)    {      counter = mlist->method_count - 1;      while (counter >= 0)        {          Method_t method = &(mlist->method_list[counter]);	  sarray_at_put_safe (class->dtable,			      (sidx) method->method_name->sel_id,			      method->method_imp);          counter -= 1;        }    }}void __objc_update_dispatch_table_for_class (Class class){  Class next;  /* not yet installed -- skip it */  if (class->dtable == __objc_uninstalled_dtable)     return;  sarray_free (class->dtable);	/* release memory */  __objc_install_premature_dtable (class); /* someone might require it... */  __objc_install_dispatch_table_for_class (class); /* could have been lazy... */  if (class->subclass_list)	/* Traverse subclasses */    for (next = class->subclass_list; next; next = next->sibling_class)      __objc_update_dispatch_table_for_class (next);}/* This function adds a method list to a class.  This function is   typically called by another function specific to the run-time.  As   such this function does not worry about thread safe issued.   This one is only called for categories. Class objects have their   methods installed right away, and their selectors are made into   SEL's by the function __objc_register_selectors_from_class. */ voidclass_add_method_list (Class class, MethodList_t list){  int i;  static SEL initialize_sel = 0;  if (!initialize_sel)    initialize_sel = sel_register_name ("initialize");  /* Passing of a linked list is not allowed.  Do multiple calls.  */  assert (!list->method_next);  /* Check for duplicates.  */  for (i = 0; i < list->method_count; ++i)    {      Method_t method = &list->method_list[i];      if (method->method_name)  /* Sometimes these are NULL */	{	  /* This is where selector names are transmogrified to SEL's */	  method->method_name = 	    sel_register_typed_name ((const char*)method->method_name,				     method->method_types);	  if (search_for_method_in_list (class->methods, method->method_name)	      && method->method_name->sel_id != initialize_sel->sel_id)	    {	      /* Duplication. Print a error message an change the method name		 to NULL. */	      fprintf (stderr, "attempt to add a existing method: %s\n",		       sel_get_name(method->method_name));	      method->method_name = 0;	    }	}    }  /* Add the methods to the class's method list.  */  list->method_next = class->methods;  class->methods = list;}Method_tclass_get_instance_method(Class class, SEL op){  return search_for_method_in_hierarchy(class, op);}Method_tclass_get_class_method(MetaClass class, SEL op){  return search_for_method_in_hierarchy(class, op);}/* Search for a method starting from the current class up its hierarchy.   Return a pointer to the method's method structure if found.  NULL   otherwise. */   static Method_tsearch_for_method_in_hierarchy (Class cls, SEL sel){  Method_t method = NULL;  Class class;  if (! sel_is_mapped (sel))    return NULL;  /* Scan the method list of the class.  If the method isn't found in the     list then step to its super class. */  for (class = cls; ((! method) && class); class = class->super_class)    method = search_for_method_in_list (class->methods, sel);  return method;}/* Given a linked list of method and a method's name.  Search for the named   method's method structure.  Return a pointer to the method's method   structure if found.  NULL otherwise. */  static Method_tsearch_for_method_in_list (MethodList_t list, SEL op){  MethodList_t method_list = list;  if (! sel_is_mapped (op))    return NULL;  /* If not found then we'll search the list.  */  while (method_list)    {      int i;      /* Search the method list.  */      for (i = 0; i < method_list->method_count; ++i)        {          Method_t method = &method_list->method_list[i];          if (method->method_name)            if (method->method_name->sel_id == op->sel_id)              return method;        }      /* The method wasn't found.  Follow the link to the next list of         methods.  */      method_list = method_list->method_next;    }  return NULL;}static retval_t __objc_forward (id object, SEL sel, arglist_t args);static id__objc_word_forward (id rcv, SEL op, ...){  void *args, *res;  args = __builtin_apply_args ();  res = __objc_forward (rcv, op, args);  if (res)    __builtin_return (res);  else    return res;}#if INVISIBLE_STRUCT_RETURNstatic __big#elsestatic id#endif__objc_block_forward (id rcv, SEL op, ...){  void *args, *res;  args = __builtin_apply_args ();  res = __objc_forward (rcv, op, args);  if (res)    __builtin_return (res);}/* This function is installed in the dispatch table for all methods which are   not implemented.  Thus, it is called when a selector is not recognized. */static retval_t__objc_forward (id object, SEL sel, arglist_t args){  IMP imp;  static SEL frwd_sel = 0;  SEL err_sel;  /* first try if the object understands forward:: */  if (!frwd_sel)    frwd_sel = sel_get_any_uid("forward::");  if (__objc_responds_to (object, frwd_sel))    {      imp = get_imp(object->class_pointer, frwd_sel);      return (*imp)(object, frwd_sel, sel, args);    }  /* If the object recognizes the doesNotRecognize: method then we're going     to send it. */  err_sel = sel_get_any_uid ("doesNotRecognize:");  if (__objc_responds_to (object, err_sel))    {      imp = get_imp (object->class_pointer, err_sel);      return (*imp) (object, err_sel, sel);    }    /* The object doesn't recognize the method.  Check for responding to     error:.  If it does then sent it. */  {    size_t strlen (const char*);    char msg[256 + strlen ((const char*)sel_get_name (sel))             + strlen ((const char*)object->class_pointer->name)];    sprintf (msg, "(%s) %s does not recognize %s",	     (CLS_ISMETA(object->class_pointer)	      ? "class"	      : "instance" ),             object->class_pointer->name, sel_get_name (sel));    err_sel = sel_get_any_uid ("error:");    if (__objc_responds_to (object, err_sel))      {	imp = get_imp (object->class_pointer, err_sel);	return (*imp) (object, sel_get_any_uid ("error:"), msg);      }    /* The object doesn't respond to doesNotRecognize: or error:;  Therefore,       a default action is taken. */    fprintf (stderr, "fatal: %s\n", msg);    abort ();  }}void __objc_print_dtable_stats(){  int total = 0;  printf("memory usage: (%s)\n",#ifdef OBJC_SPARSE2	 "2-level sparse arrays"#else	 "3-level sparse arrays"#endif	 );  printf("arrays: %d = %ld bytes\n", narrays, (int)narrays*sizeof(struct sarray));  total += narrays*sizeof(struct sarray);  printf("buckets: %d = %ld bytes\n", nbuckets, (int)nbuckets*sizeof(struct sbucket));  total += nbuckets*sizeof(struct sbucket);  printf("idxtables: %d = %ld bytes\n", idxsize, (int)idxsize*sizeof(void*));  total += idxsize*sizeof(void*);  printf("-----------------------------------\n");  printf("total: %d bytes\n", total);  printf("===================================\n");}