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/*
* Heap Buffer object representation. Used for all Buffer variants.
*/
#if !defined(DUK_HBUFOBJ_H_INCLUDED)
#define DUK_HBUFOBJ_H_INCLUDED
#if defined(DUK_USE_BUFFEROBJECT_SUPPORT)
/* All element accessors are host endian now (driven by TypedArray spec). */
#define DUK_HBUFOBJ_ELEM_UINT8 0
#define DUK_HBUFOBJ_ELEM_UINT8CLAMPED 1
#define DUK_HBUFOBJ_ELEM_INT8 2
#define DUK_HBUFOBJ_ELEM_UINT16 3
#define DUK_HBUFOBJ_ELEM_INT16 4
#define DUK_HBUFOBJ_ELEM_UINT32 5
#define DUK_HBUFOBJ_ELEM_INT32 6
#define DUK_HBUFOBJ_ELEM_FLOAT32 7
#define DUK_HBUFOBJ_ELEM_FLOAT64 8
#define DUK_HBUFOBJ_ELEM_MAX 8
#if defined(DUK_USE_ASSERTIONS)
DUK_INTERNAL_DECL void duk_hbufobj_assert_valid(duk_hbufobj *h);
#define DUK_HBUFOBJ_ASSERT_VALID(h) \
do { \
duk_hbufobj_assert_valid((h)); \
} while (0)
#else
#define DUK_HBUFOBJ_ASSERT_VALID(h) \
do { \
} while (0)
#endif
/* Get the current data pointer (caller must ensure buf != NULL) as a
* duk_uint8_t ptr. Note that the result may be NULL if the underlying
* buffer has zero size and is not a fixed buffer.
*/
#define DUK_HBUFOBJ_GET_SLICE_BASE(heap, h) \
(DUK_ASSERT_EXPR((h) != NULL), \
DUK_ASSERT_EXPR((h)->buf != NULL), \
(((duk_uint8_t *) DUK_HBUFFER_GET_DATA_PTR((heap), (h)->buf)) + (h)->offset))
/* True if slice is full, i.e. offset is zero and length covers the entire
* buffer. This status may change independently of the duk_hbufobj if
* the underlying buffer is dynamic and changes without the hbufobj
* being changed.
*/
#define DUK_HBUFOBJ_FULL_SLICE(h) \
(DUK_ASSERT_EXPR((h) != NULL), \
DUK_ASSERT_EXPR((h)->buf != NULL), \
((h)->offset == 0 && (h)->length == DUK_HBUFFER_GET_SIZE((h)->buf)))
/* Validate that the whole slice [0,length[ is contained in the underlying
* buffer. Caller must ensure 'buf' != NULL.
*/
#define DUK_HBUFOBJ_VALID_SLICE(h) \
(DUK_ASSERT_EXPR((h) != NULL), \
DUK_ASSERT_EXPR((h)->buf != NULL), \
((h)->offset + (h)->length <= DUK_HBUFFER_GET_SIZE((h)->buf)))
/* Validate byte read/write for virtual 'offset', i.e. check that the
* offset, taking into account h->offset, is within the underlying
* buffer size. This is a safety check which is needed to ensure
* that even a misconfigured duk_hbufobj never causes memory unsafe
* behavior (e.g. if an underlying dynamic buffer changes after being
* setup). Caller must ensure 'buf' != NULL.
*/
#define DUK_HBUFOBJ_VALID_BYTEOFFSET_INCL(h, off) \
(DUK_ASSERT_EXPR((h) != NULL), DUK_ASSERT_EXPR((h)->buf != NULL), ((h)->offset + (off) < DUK_HBUFFER_GET_SIZE((h)->buf)))
#define DUK_HBUFOBJ_VALID_BYTEOFFSET_EXCL(h, off) \
(DUK_ASSERT_EXPR((h) != NULL), DUK_ASSERT_EXPR((h)->buf != NULL), ((h)->offset + (off) <= DUK_HBUFFER_GET_SIZE((h)->buf)))
/* Clamp an input byte length (already assumed to be within the nominal
* duk_hbufobj 'length') to the current dynamic buffer limits to yield
* a byte length limit that's safe for memory accesses. This value can
* be invalidated by any side effect because it may trigger a user
* callback that resizes the underlying buffer.
*/
#define DUK_HBUFOBJ_CLAMP_BYTELENGTH(h, len) (DUK_ASSERT_EXPR((h) != NULL), duk_hbufobj_clamp_bytelength((h), (len)))
/* Typed arrays have virtual indices, ArrayBuffer and DataView do not. */
#define DUK_HBUFOBJ_HAS_VIRTUAL_INDICES(h) ((h)->is_typedarray)
struct duk_hbufobj {
/* Shared object part. */
duk_hobject obj;
/* Underlying buffer (refcounted), may be NULL. */
duk_hbuffer *buf;
/* .buffer reference to an ArrayBuffer, may be NULL. */
duk_hobject *buf_prop;
/* Slice and accessor information.
*
* Because the underlying buffer may be dynamic, these may be
* invalidated by the buffer being modified so that both offset
* and length should be validated before every access. Behavior
* when the underlying buffer has changed doesn't need to be clean:
* virtual 'length' doesn't need to be affected, reads can return
* zero/NaN, and writes can be ignored.
*
* Note that a data pointer cannot be precomputed because 'buf' may
* be dynamic and its pointer unstable.
*/
duk_uint_t offset; /* byte offset to buf */
duk_uint_t length; /* byte index limit for element access, exclusive */
duk_uint8_t shift; /* element size shift:
* 0 = u8/i8
* 1 = u16/i16
* 2 = u32/i32/float
* 3 = double
*/
duk_uint8_t elem_type; /* element type */
duk_uint8_t is_typedarray;
};
DUK_INTERNAL_DECL duk_uint_t duk_hbufobj_clamp_bytelength(duk_hbufobj *h_bufobj, duk_uint_t len);
DUK_INTERNAL_DECL void duk_hbufobj_push_uint8array_from_plain(duk_hthread *thr, duk_hbuffer *h_buf);
DUK_INTERNAL_DECL void duk_hbufobj_push_validated_read(duk_hthread *thr,
duk_hbufobj *h_bufobj,
duk_uint8_t *p,
duk_small_uint_t elem_size);
DUK_INTERNAL_DECL void duk_hbufobj_validated_write(duk_hthread *thr,
duk_hbufobj *h_bufobj,
duk_uint8_t *p,
duk_small_uint_t elem_size);
DUK_INTERNAL_DECL void duk_hbufobj_promote_plain(duk_hthread *thr, duk_idx_t idx);
#else /* DUK_USE_BUFFEROBJECT_SUPPORT */
/* nothing */
#endif /* DUK_USE_BUFFEROBJECT_SUPPORT */
#endif /* DUK_HBUFOBJ_H_INCLUDED */
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