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/*
* Copyright (c) 2008, 2009, Wayne Meissner
*
* Copyright (c) 2008-2013, Ruby FFI project contributors
* All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions are met:
* * Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* * Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
* * Neither the name of the Ruby FFI project nor the
* names of its contributors may be used to endorse or promote products
* derived from this software without specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS" AND
* ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
* WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
* DISCLAIMED. IN NO EVENT SHALL <COPYRIGHT HOLDER> BE LIABLE FOR ANY
* DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
* (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
* LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND
* ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
* (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
* SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
*/
#ifndef _MSC_VER
# include <stdint.h>
# include <stdbool.h>
#else
# include "win32/stdint.h"
# include "win32/stdbool.h"
#endif
#include <limits.h>
#include <ruby.h>
#include "rbffi.h"
#include "rbffi_endian.h"
#include "AbstractMemory.h"
#include "Pointer.h"
#define POINTER(obj) rbffi_AbstractMemory_Cast((obj), rbffi_PointerClass)
VALUE rbffi_PointerClass = Qnil;
VALUE rbffi_NullPointerSingleton = Qnil;
static void ptr_release(Pointer* ptr);
static void ptr_mark(Pointer* ptr);
VALUE
rbffi_Pointer_NewInstance(void* addr)
{
Pointer* p;
VALUE obj;
if (addr == NULL) {
return rbffi_NullPointerSingleton;
}
obj = Data_Make_Struct(rbffi_PointerClass, Pointer, NULL, -1, p);
p->memory.address = addr;
p->memory.size = LONG_MAX;
p->memory.flags = (addr == NULL) ? 0 : (MEM_RD | MEM_WR);
p->memory.typeSize = 1;
p->rbParent = Qnil;
return obj;
}
static VALUE
ptr_allocate(VALUE klass)
{
Pointer* p;
VALUE obj;
obj = Data_Make_Struct(klass, Pointer, ptr_mark, ptr_release, p);
p->rbParent = Qnil;
p->memory.flags = MEM_RD | MEM_WR;
return obj;
}
/*
* @overload initialize(pointer)
* @param [Pointer] pointer another pointer to initialize from
* Create a new pointer from another {Pointer}.
* @overload initialize(type, address)
* @param [Type] type type for pointer
* @param [Integer] address base address for pointer
* Create a new pointer from a {Type} and a base address
* @return [self]
* A new instance of Pointer.
*/
static VALUE
ptr_initialize(int argc, VALUE* argv, VALUE self)
{
Pointer* p;
VALUE rbType = Qnil, rbAddress = Qnil;
int typeSize = 1;
Data_Get_Struct(self, Pointer, p);
switch (rb_scan_args(argc, argv, "11", &rbType, &rbAddress)) {
case 1:
rbAddress = rbType;
typeSize = 1;
break;
case 2:
typeSize = rbffi_type_size(rbType);
break;
default:
rb_raise(rb_eArgError, "Invalid arguments");
}
switch (TYPE(rbAddress)) {
case T_FIXNUM:
case T_BIGNUM:
p->memory.address = (void*) (uintptr_t) NUM2LL(rbAddress);
p->memory.size = LONG_MAX;
if (p->memory.address == NULL) {
p->memory.flags = 0;
}
break;
default:
if (rb_obj_is_kind_of(rbAddress, rbffi_PointerClass)) {
Pointer* orig;
p->rbParent = rbAddress;
Data_Get_Struct(rbAddress, Pointer, orig);
p->memory = orig->memory;
} else {
rb_raise(rb_eTypeError, "wrong argument type, expected Integer or FFI::Pointer");
}
break;
}
p->memory.typeSize = typeSize;
return self;
}
/*
* call-seq: ptr.initialize_copy(other)
* @param [Pointer] other source for cloning or dupping
* @return [self]
* @raise {RuntimeError} if +other+ is an unbounded memory area, or is unreadable/unwritable
* @raise {NoMemError} if failed to allocate memory for new object
* DO NOT CALL THIS METHOD.
*
* This method is internally used by #dup and #clone. Memory content is copied from +other+.
*/
static VALUE
ptr_initialize_copy(VALUE self, VALUE other)
{
AbstractMemory* src;
Pointer* dst;
Data_Get_Struct(self, Pointer, dst);
src = POINTER(other);
if (src->size == LONG_MAX) {
rb_raise(rb_eRuntimeError, "cannot duplicate unbounded memory area");
return Qnil;
}
if ((dst->memory.flags & (MEM_RD | MEM_WR)) != (MEM_RD | MEM_WR)) {
rb_raise(rb_eRuntimeError, "cannot duplicate unreadable/unwritable memory area");
return Qnil;
}
if (dst->storage != NULL) {
xfree(dst->storage);
dst->storage = NULL;
}
dst->storage = xmalloc(src->size + 7);
if (dst->storage == NULL) {
rb_raise(rb_eNoMemError, "failed to allocate memory size=%lu bytes", src->size);
return Qnil;
}
dst->allocated = true;
dst->autorelease = true;
dst->memory.address = (void *) (((uintptr_t) dst->storage + 0x7) & (uintptr_t) ~0x7UL);
dst->memory.size = src->size;
dst->memory.typeSize = src->typeSize;
/* finally, copy the actual memory contents */
memcpy(dst->memory.address, src->address, src->size);
return self;
}
static VALUE
slice(VALUE self, long offset, long size)
{
AbstractMemory* ptr;
Pointer* p;
VALUE retval;
Data_Get_Struct(self, AbstractMemory, ptr);
checkBounds(ptr, offset, size == LONG_MAX ? 1 : size);
retval = Data_Make_Struct(rbffi_PointerClass, Pointer, ptr_mark, -1, p);
p->memory.address = ptr->address + offset;
p->memory.size = size;
p->memory.flags = ptr->flags;
p->memory.typeSize = ptr->typeSize;
p->rbParent = self;
return retval;
}
/*
* Document-method: +
* call-seq: ptr + offset
* @param [Numeric] offset
* @return [Pointer]
* Return a new {Pointer} from an existing pointer and an +offset+.
*/
static VALUE
ptr_plus(VALUE self, VALUE offset)
{
AbstractMemory* ptr;
long off = NUM2LONG(offset);
Data_Get_Struct(self, AbstractMemory, ptr);
return slice(self, off, ptr->size == LONG_MAX ? LONG_MAX : ptr->size - off);
}
/*
* call-seq: ptr.slice(offset, length)
* @param [Numeric] offset
* @param [Numeric] length
* @return [Pointer]
* Return a new {Pointer} from an existing one. This pointer points on same contents
* from +offset+ for a length +length+.
*/
static VALUE
ptr_slice(VALUE self, VALUE rbOffset, VALUE rbLength)
{
return slice(self, NUM2LONG(rbOffset), NUM2LONG(rbLength));
}
/*
* call-seq: ptr.inspect
* @return [String]
* Inspect pointer object.
*/
static VALUE
ptr_inspect(VALUE self)
{
char buf[100];
Pointer* ptr;
Data_Get_Struct(self, Pointer, ptr);
if (ptr->memory.size != LONG_MAX) {
snprintf(buf, sizeof(buf), "#<%s address=%p size=%lu>",
rb_obj_classname(self), ptr->memory.address, ptr->memory.size);
} else {
snprintf(buf, sizeof(buf), "#<%s address=%p>", rb_obj_classname(self), ptr->memory.address);
}
return rb_str_new2(buf);
}
/*
* Document-method: null?
* call-seq: ptr.null?
* @return [Boolean]
* Return +true+ if +self+ is a {NULL} pointer.
*/
static VALUE
ptr_null_p(VALUE self)
{
Pointer* ptr;
Data_Get_Struct(self, Pointer, ptr);
return ptr->memory.address == NULL ? Qtrue : Qfalse;
}
/*
* Document-method: ==
* call-seq: ptr == other
* @param [Pointer] other
* Check equality between +self+ and +other+. Equality is tested on {#address}.
*/
static VALUE
ptr_equals(VALUE self, VALUE other)
{
Pointer* ptr;
Data_Get_Struct(self, Pointer, ptr);
if (NIL_P(other)) {
return ptr->memory.address == NULL ? Qtrue : Qfalse;
}
return ptr->memory.address == POINTER(other)->address ? Qtrue : Qfalse;
}
/*
* call-seq: ptr.address
* @return [Numeric] pointer's base address
* Return +self+'s base address (alias: #to_i).
*/
static VALUE
ptr_address(VALUE self)
{
Pointer* ptr;
Data_Get_Struct(self, Pointer, ptr);
return ULL2NUM((uintptr_t) ptr->memory.address);
}
#if BYTE_ORDER == LITTLE_ENDIAN
# define SWAPPED_ORDER BIG_ENDIAN
#else
# define SWAPPED_ORDER LITTLE_ENDIAN
#endif
/*
* Get or set +self+'s endianness
* @overload order
* @return [:big, :little] endianness of +self+
* @overload order(order)
* @param [Symbol] order endianness to set (+:little+, +:big+ or +:network+). +:big+ and +:network+
* are synonymous.
* @return [self]
*/
static VALUE
ptr_order(int argc, VALUE* argv, VALUE self)
{
Pointer* ptr;
Data_Get_Struct(self, Pointer, ptr);
if (argc == 0) {
int order = (ptr->memory.flags & MEM_SWAP) == 0 ? BYTE_ORDER : SWAPPED_ORDER;
return order == BIG_ENDIAN ? ID2SYM(rb_intern("big")) : ID2SYM(rb_intern("little"));
} else {
VALUE rbOrder = Qnil;
int order = BYTE_ORDER;
if (rb_scan_args(argc, argv, "1", &rbOrder) < 1) {
rb_raise(rb_eArgError, "need byte order");
}
if (SYMBOL_P(rbOrder)) {
ID id = SYM2ID(rbOrder);
if (id == rb_intern("little")) {
order = LITTLE_ENDIAN;
} else if (id == rb_intern("big") || id == rb_intern("network")) {
order = BIG_ENDIAN;
}
}
if (order != BYTE_ORDER) {
Pointer* p2;
VALUE retval = slice(self, 0, ptr->memory.size);
Data_Get_Struct(retval, Pointer, p2);
p2->memory.flags |= MEM_SWAP;
return retval;
}
return self;
}
}
/*
* call-seq: ptr.free
* @return [self]
* Free memory pointed by +self+.
*/
static VALUE
ptr_free(VALUE self)
{
Pointer* ptr;
Data_Get_Struct(self, Pointer, ptr);
if (ptr->allocated) {
if (ptr->storage != NULL) {
xfree(ptr->storage);
ptr->storage = NULL;
}
ptr->allocated = false;
} else {
VALUE caller = rb_funcall(rb_funcall(Qnil, rb_intern("caller"), 0), rb_intern("first"), 0);
rb_warn("calling free on non allocated pointer %s from %s", RSTRING_PTR(ptr_inspect(self)), RSTRING_PTR(rb_str_to_str(caller)));
}
return self;
}
static VALUE
ptr_type_size(VALUE self)
{
Pointer* ptr;
Data_Get_Struct(self, Pointer, ptr);
return INT2NUM(ptr->memory.typeSize);
}
/*
* call-seq: ptr.autorelease = autorelease
* @param [Boolean] autorelease
* @return [Boolean] +autorelease+
* Set +autorelease+ attribute. See also Autorelease section.
*/
static VALUE
ptr_autorelease(VALUE self, VALUE autorelease)
{
Pointer* ptr;
Data_Get_Struct(self, Pointer, ptr);
ptr->autorelease = autorelease == Qtrue;
return autorelease;
}
/*
* call-seq: ptr.autorelease?
* @return [Boolean]
* Get +autorelease+ attribute. See also Autorelease section.
*/
static VALUE
ptr_autorelease_p(VALUE self)
{
Pointer* ptr;
Data_Get_Struct(self, Pointer, ptr);
return ptr->autorelease ? Qtrue : Qfalse;
}
static void
ptr_release(Pointer* ptr)
{
if (ptr->autorelease && ptr->allocated && ptr->storage != NULL) {
xfree(ptr->storage);
ptr->storage = NULL;
}
xfree(ptr);
}
static void
ptr_mark(Pointer* ptr)
{
rb_gc_mark(ptr->rbParent);
}
void
rbffi_Pointer_Init(VALUE moduleFFI)
{
VALUE rbNullAddress = ULL2NUM(0);
VALUE ffi_AbstractMemory = rbffi_AbstractMemoryClass;
/*
* Document-class: FFI::Pointer < FFI::AbstractMemory
* Pointer class is used to manage C pointers with ease. A {Pointer} object is defined by his
* {#address} (as a C pointer). It permits additions with an integer for pointer arithmetic.
*
* ==Autorelease
* A pointer object may autorelease his contents when freed (by default). This behaviour may be
* changed with {#autorelease=} method.
*/
rbffi_PointerClass = rb_define_class_under(moduleFFI, "Pointer", ffi_AbstractMemory);
/*
* Document-variable: Pointer
*/
rb_global_variable(&rbffi_PointerClass);
rb_define_alloc_func(rbffi_PointerClass, ptr_allocate);
rb_define_method(rbffi_PointerClass, "initialize", ptr_initialize, -1);
rb_define_method(rbffi_PointerClass, "initialize_copy", ptr_initialize_copy, 1);
rb_define_method(rbffi_PointerClass, "inspect", ptr_inspect, 0);
rb_define_method(rbffi_PointerClass, "to_s", ptr_inspect, 0);
rb_define_method(rbffi_PointerClass, "+", ptr_plus, 1);
rb_define_method(rbffi_PointerClass, "slice", ptr_slice, 2);
rb_define_method(rbffi_PointerClass, "null?", ptr_null_p, 0);
rb_define_method(rbffi_PointerClass, "address", ptr_address, 0);
rb_define_alias(rbffi_PointerClass, "to_i", "address");
rb_define_method(rbffi_PointerClass, "==", ptr_equals, 1);
rb_define_method(rbffi_PointerClass, "order", ptr_order, -1);
rb_define_method(rbffi_PointerClass, "autorelease=", ptr_autorelease, 1);
rb_define_method(rbffi_PointerClass, "autorelease?", ptr_autorelease_p, 0);
rb_define_method(rbffi_PointerClass, "free", ptr_free, 0);
rb_define_method(rbffi_PointerClass, "type_size", ptr_type_size, 0);
rbffi_NullPointerSingleton = rb_class_new_instance(1, &rbNullAddress, rbffi_PointerClass);
/*
* NULL pointer
*/
rb_define_const(rbffi_PointerClass, "NULL", rbffi_NullPointerSingleton);
}
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