pike.git/ src/ builtin.cmod

Branch: Tag:

2019-05-04

2019-05-04 12:37:55 by Henrik Grubbström (Grubba) <grubba@grubba.org>

Pike.ProxyFactory: Added new function.

This is a factory for creating classes that act as a proxy
for the specified program.

1607:    push_int(0);   }    + static void f_proxy_create(INT32 args) + { +  struct object *o; +  struct program *p; +  struct program *expected; +  if (args != 1) { +  wrong_number_of_args_error("create", args, 1); +  } +  if (TYPEOF(Pike_sp[-1]) != PIKE_T_OBJECT) { +  SIMPLE_ARG_TYPE_ERROR("create", 1, "object"); +  } +  expected = Pike_fp->context->prog->constants[1].sval.u.program; +  o = Pike_sp[-1].u.object; +  p = o->prog; +  if (!p) { +  Pike_error("Destructed object.\n"); +  } +  p = p->inherits[SUBTYPEOF(Pike_sp[-1])].prog; +  if (p != expected) { +  int e; +  int found = 0; +  for (e = 1; e < p->num_inherits; e++) { +  if (p->inherits[e].prog == expected) { +  /* Found */ +  if ((found) && +  (p->inherits[found].inherit_level <= p->inherits[e].inherit_level)) +  continue; +  found = e; +  } +  } +  if (found) { +  SET_SVAL_SUBTYPE(Pike_sp[-1], SUBTYPEOF(Pike_sp[-1]) + found); +  } +  } +  object_low_set_index(Pike_fp->current_object, +  Pike_fp->context->identifier_level + 0, +  Pike_sp-1); + } +  + /** +  * Look up the reference in the wrapped object +  * corresponding to the current function. +  */ + static int low_proxy_ref(void) + { +  /* Note that we index on the identifier offset, +  * NOT the reference number, as more references +  * may get added on demand via eg local::, etc. +  */ +  struct reference *ref = +  PTR_FROM_INT(Pike_fp->context->prog, +  Pike_fp->fun - Pike_fp->context->identifier_level); +  struct array *a = Pike_fp->context->prog->constants[0].sval.u.array; +  return ITEM(a)[ref->identifier_offset].u.integer; + } +  + static void f_proxy_getter(INT32 args) + { +  struct program *expected = +  Pike_fp->context->prog->constants[1].sval.u.program; +  int proxy_ref = low_proxy_ref(); +  /* NB: We only have a single variable i storage. */ +  struct svalue *storage = (struct svalue *)Pike_fp->current_storage; +  struct object *obj; +  struct inherit *inh; +  struct identifier *id; +  +  if (args) { +  wrong_number_of_args_error(NULL, args, 0); +  } +  +  if (TYPEOF(*storage) != PIKE_T_OBJECT) { +  Pike_error("Proxy for %O not initialized.\n", +  Pike_fp->context->prog->constants + 1); +  } +  +  obj = storage->u.object; +  if (!obj->prog) { +  Pike_error("Proxied object has been destructed.\n"); +  } +  inh = obj->prog->inherits + SUBTYPEOF(*storage); +  +  if (inh->prog == expected) { +  low_object_index_no_free(Pike_sp, obj, inh->identifier_level + proxy_ref); +  Pike_sp++; +  return; +  } +  +  /* Attempt to index the object anyway. */ +  id = ID_FROM_INT(expected, proxy_ref); +  ref_push_string(id->name); +  object_index_no_free(Pike_sp, obj, SUBTYPEOF(*storage), Pike_sp-1); +  Pike_sp++; + } +  + static void f_proxy_setter(INT32 args) + { +  struct program *expected = +  Pike_fp->context->prog->constants[1].sval.u.program; +  int proxy_ref = low_proxy_ref(); +  /* NB: We only have a single variable i storage. */ +  struct svalue *storage = (struct svalue *)Pike_fp->current_storage; +  struct object *obj; +  struct inherit *inh; +  struct identifier *id; +  +  if (args != 1) { +  wrong_number_of_args_error(NULL, args, 1); +  } +  +  if (TYPEOF(*storage) != PIKE_T_OBJECT) { +  Pike_error("Proxy for %O not initialized.\n", +  &Pike_fp->context->prog->constants[1].sval); +  } +  +  obj = storage->u.object; +  if (!obj->prog) { +  Pike_error("Proxied object has been destructed.\n"); +  } +  inh = obj->prog->inherits + SUBTYPEOF(*storage); +  +  if (inh->prog == expected) { +  object_low_set_index(obj, inh->identifier_level + proxy_ref, Pike_sp-args); +  return; +  } +  +  /* Attempt to set the index in the object anyway. */ +  id = ID_FROM_INT(expected, proxy_ref); +  ref_push_string(id->name); +  object_set_index(obj, SUBTYPEOF(*storage), Pike_sp-1, Pike_sp-(args+1)); + } +  + static void f_proxy_fun(INT32 args) + { +  struct program *expected = +  Pike_fp->context->prog->constants[1].sval.u.program; +  int proxy_ref = low_proxy_ref(); +  /* NB: We only have a single variable i storage. */ +  struct svalue *storage = (struct svalue *)Pike_fp->current_storage; +  struct object *obj; +  struct inherit *inh; +  struct identifier *id; +  +  if (TYPEOF(*storage) != PIKE_T_OBJECT) { +  Pike_error("Proxy for %O not initialized.\n", +  Pike_fp->context->prog->constants + 1); +  } +  +  obj = storage->u.object; +  if (!obj->prog) { +  Pike_error("Proxied object has been destructed.\n"); +  } +  inh = obj->prog->inherits + SUBTYPEOF(*storage); +  +  if (inh->prog == expected) { +  apply_low(obj, inh->identifier_level + proxy_ref, args); +  return; +  } +  +  /* Attempt to apply the symbol in the object anyway. */ +  /* FIXME: Doesn't care about the object subtype! */ +  id = ID_FROM_INT(expected, proxy_ref); +  apply_shared(obj, id->name, args); + } +  + static void f_proxy__sprintf(INT32 args) + { +  struct program *expected = +  Pike_fp->context->prog->constants[1].sval.u.program; +  int proxy_ref = low_proxy_ref(); +  /* NB: We only have a single variable in storage. */ +  struct svalue *storage = (struct svalue *)Pike_fp->current_storage; +  struct object *obj; +  struct inherit *inh; +  struct identifier *id; +  +  if (TYPEOF(*storage) != PIKE_T_OBJECT) { +  Pike_error("Proxy for %O not initialized.\n", +  Pike_fp->context->prog->constants + 1); +  } +  +  obj = storage->u.object; +  if (!obj->prog) { +  Pike_error("Proxied object has been destructed.\n"); +  } +  +  if (args && (TYPEOF(Pike_sp[-args]) == T_INT) && +  (Pike_sp[-args].u.integer == 'O')) { +  /* Special case for debug mode. */ +  push_constant_text("%O(%O)"); +  ref_push_program(Pike_fp->current_object->prog); +  push_svalue(storage); +  f_sprintf(3); +  return; +  } +  +  if (proxy_ref < 0) { +  push_undefined(); +  return; +  } +  +  apply_lfun(obj, LFUN__SPRINTF, args); + } +  + static struct mapping *proxy_lookup = NULL; + /*! @decl program ProxyFactory(program p) +  *! +  *! Create a class that acts as a proxy for the specified program. +  *! +  *! @param p +  *! Program to generate a proxy for. +  *! +  *! The generated class will have the same symbols (public and +  *! private) with the same types as in @[p], where accesses to +  *! these will proxy the access to the same symbol in the proxied +  *! (aka wrapped) object. With the following exceptions: +  *! +  *! @dl +  *! @item @expr{protected void create(object(p) obj)@} +  *! Initialize the object to act as a proxy for @expr{obj@}. +  *! +  *! @item @expr{_sprintf(int c, mapping|void params)@} +  *! Special case for @expr{c@} == @expr{'O'@}, where +  *! it will return @expr{sprintf("%O(%O)", this_program, obj)@}, +  *! and otherwise proxy the call. +  *! +  *! @item @expr{void _destruct()@}/@expr{void destroy()@} +  *! These lfuns will not be present as the act of them +  *! being proxied would likely confuse the proxied object. +  *! @enddl +  *! +  *! @note +  *! The same proxy class will be returned if this function +  *! is called with the same program multiple times. +  */ + PIKEFUN program ProxyFactory(program p) +  optflags OPT_TRY_OPTIMIZE; +  rawtype tFunc(tSetvar(0, tPrg(tObj)), tVar(0)); + { +  struct array *a; +  int i = 0; +  struct pike_type *fun_type; +  union idptr ptr; +  int j; +  struct svalue *cached; +  +  ref_push_program(p); +  if (proxy_lookup && +  (cached = low_mapping_lookup(proxy_lookup, Pike_sp-1))) { +  push_svalue(cached); +  return; +  } +  /* NB: Keep the program on the stack, we will use it +  * later when we update the proxy_lookup cache. +  */ +  +  enter_compiler(NULL, 0); +  start_new_program(); +  +  /* Constant #0: The mapping from local reference # to external d:o. */ +  /* NB: Over allocation. */ +  /* NB: For the lookup to work as intended all functions that use +  * this array *need* to be declared ID_LOCAL to avoid being +  * renumbered when overloaded. +  */ +  push_int((p->num_identifier_references+1) * 3); +  push_int(-1); +  f_allocate(2); +  a = Pike_sp[-1].u.array; +  store_constant(Pike_sp-1, 0, NULL); +  +  /* Constant #1: The program that we intend to wrap. */ +  ref_push_program(p); +  store_constant(Pike_sp-1, 0, NULL); +  +  /* Reference #0: The variable that we store the proxied object in. */ +  /* NB: Use a name that will not clash. */ +  push_string(make_shared_static_string("proxied_obj\0", 12, eightbit)); +  type_stack_mark(); +  push_object_type(0, p->id); +  fun_type = pop_unfinished_type(); +  define_variable(Pike_sp[-1].u.string, fun_type, +  ID_LOCAL|ID_PROTECTED|ID_PRIVATE|ID_HIDDEN); +  free_type(fun_type); +  pop_stack(); +  +  /* Add proxy functions for the references. */ +  for (i = 0; i < p->num_identifier_references; i++) { +  struct reference *ref = PTR_FROM_INT(p, i); +  struct identifier *id; +  if (ref->id_flags & ID_HIDDEN) continue; +  id = ID_FROM_PTR(p, ref); +  if (IDENTIFIER_IS_ALIAS(id->identifier_flags)) { +  /* Handle in second pass. */ +  yyerror("Aliases not supported (yet)."); +  } else if (IDENTIFIER_IS_VARIABLE(id->identifier_flags) || +  IDENTIFIER_IS_CONSTANT(id->identifier_flags)) { +  struct pike_string *fun_name; +  +  /* Getter. */ +  type_stack_mark(); +  push_finished_type(id->type); +  push_type(T_VOID); +  push_type(T_MANY); +  fun_type = pop_unfinished_type(); +  push_static_text("`"); +  ref_push_string(id->name); +  f_add(2); +  ptr.c_fun = f_proxy_getter; +  j = define_function(Pike_sp[-1].u.string, fun_type, +  ref->id_flags | ID_LOCAL, +  IDENTIFIER_C_FUNCTION, &ptr, 0); +  SET_SVAL(ITEM(a)[PTR_FROM_INT(Pike_compiler->new_program, j)-> +  identifier_offset], T_INT, NUMBER_NUMBER, integer, i); +  free_type(fun_type); +  +  if (IDENTIFIER_IS_VARIABLE(id->identifier_flags)) { +  /* Setter. */ +  type_stack_mark(); +  push_type(T_VOID); +  push_type(T_VOID); +  push_type(T_MANY); +  push_finished_type(id->type); +  push_type(T_FUNCTION); +  fun_type = pop_unfinished_type(); +  push_static_text("="); +  f_add(2); +  ptr.c_fun = f_proxy_setter; +  j = define_function(Pike_sp[-1].u.string, fun_type, +  ref->id_flags | ID_LOCAL, +  IDENTIFIER_C_FUNCTION, &ptr, 0); +  SET_SVAL(ITEM(a)[PTR_FROM_INT(Pike_compiler->new_program, j)-> +  identifier_offset], T_INT, NUMBER_NUMBER, integer, i); +  free_type(fun_type); +  } +  +  pop_stack(); +  } else { +  /* Check if getter or setter and skip, as they are handled above. */ +  if (id->name->len && (index_shared_string(id->name, 0) == '`') && +  !is_lfun_name(id->name)) { +  /* Name starting with `, but not an lfun. +  * This is thus probably a getter or setter. +  */ +  continue; +  } +  if ((id->name == lfun_strings[LFUN_CREATE]) || +  (id->name == lfun_strings[LFUN__DESTRUCT]) || +  (id->name == compat_lfun_destroy_string) || +  (id->name == lfun_strings[LFUN__SPRINTF])) { +  /* Skip. We add a custom create() and _sprintf() below. */ +  continue; +  } +  ptr.c_fun = f_proxy_fun; +  j = define_function(id->name, id->type, ref->id_flags, +  IDENTIFIER_C_FUNCTION | ID_LOCAL, &ptr, 0); +  SET_SVAL(ITEM(a)[PTR_FROM_INT(Pike_compiler->new_program, j)-> +  identifier_offset], T_INT, NUMBER_NUMBER, integer, i); +  } +  } +  +  /* Add a suitable _sprintf(). */ +  /* FIXME! */ +  { +  int id_flags = ID_PROTECTED; +  i = FIND_LFUN(p, LFUN__SPRINTF); +  if (i >= 0) { +  struct reference *ref = PTR_FROM_INT(p, i); +  struct identifier *id = ID_FROM_PTR(p, ref); +  id_flags = ref->id_flags; +  fun_type = id->type; +  } else { +  type_stack_mark(); +  push_int_type(MIN_INT32, MAX_INT32); +  push_type(T_STRING); +  push_type(T_VOID); +  push_type(T_MANY); +  push_int_type(MIN_INT32, MAX_INT32); +  push_type(T_STRING); +  push_int_type(MIN_INT32, MAX_INT32); +  push_type(T_MAPPING); +  push_type(T_VOID); +  push_type(T_OR); +  push_type(T_FUNCTION); +  push_int_type(MIN_INT32, MAX_INT32); +  push_type(T_FUNCTION); +  fun_type = pop_unfinished_type(); +  simple_describe_type(fun_type); +  } +  ptr.c_fun = f_proxy__sprintf; +  j = define_function(lfun_strings[LFUN__SPRINTF], fun_type, +  id_flags | ID_LOCAL, +  IDENTIFIER_C_FUNCTION, &ptr, 0); +  SET_SVAL(ITEM(a)[PTR_FROM_INT(Pike_compiler->new_program, j)-> +  identifier_offset], T_INT, NUMBER_NUMBER, integer, i); +  if (i < 0) { +  free_type(fun_type); +  } +  } +  +  /* Add a suitable create(). */ +  type_stack_mark(); +  push_type(T_VOID); +  push_type(T_VOID); +  push_type(T_MANY); +  push_object_type(0, p->id); +  push_type(T_FUNCTION); +  fun_type = pop_unfinished_type(); +  ptr.c_fun = f_proxy_create; +  j = define_function(lfun_strings[LFUN_CREATE], fun_type, ID_PROTECTED, +  IDENTIFIER_C_FUNCTION, &ptr, 0); +  free_type(fun_type); +  +  p = end_program(); +  exit_compiler(); +  +  if (p) { +  push_program(p); +  +  if (!proxy_lookup) { +  proxy_lookup = allocate_mapping(10); +  mapping_set_flags(proxy_lookup, MAPPING_WEAK_INDICES); +  } +  +  mapping_insert(proxy_lookup, Pike_sp-2, Pike_sp-1); +  } else { +  push_undefined(); +  } + } +    /*! @decl int(8..8)|int(16..16)|int(32..32) width(string s)    *! @belongs String    *!
6600:   void exit_builtin(void)   {    struct svalue zero; +  if (proxy_lookup) free_mapping(proxy_lookup);    if (val_module) free_object (val_module);    EXIT;    SET_SVAL(zero, PIKE_T_INT, NUMBER_NUMBER, integer, 0);