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/*
* Misc support functions
*/
#include "duk_internal.h"
/*
* duk_hstring charCodeAt, with and without surrogate awareness
*/
DUK_INTERNAL duk_ucodepoint_t duk_hstring_char_code_at_raw(duk_hthread *thr,
duk_hstring *h,
duk_uint_t pos,
duk_bool_t surrogate_aware) {
duk_uint32_t boff;
const duk_uint8_t *p, *p_start, *p_end;
duk_ucodepoint_t cp1;
duk_ucodepoint_t cp2;
/* Caller must check character offset to be inside the string. */
DUK_ASSERT(thr != NULL);
DUK_ASSERT(h != NULL);
DUK_ASSERT_DISABLE(pos >= 0); /* unsigned */
DUK_ASSERT(pos < (duk_uint_t) DUK_HSTRING_GET_CHARLEN(h));
boff = (duk_uint32_t) duk_heap_strcache_offset_char2byte(thr, h, (duk_uint32_t) pos);
DUK_DDD(DUK_DDDPRINT("charCodeAt: pos=%ld -> boff=%ld, str=%!O", (long) pos, (long) boff, (duk_heaphdr *) h));
DUK_ASSERT_DISABLE(boff >= 0);
DUK_ASSERT(boff < DUK_HSTRING_GET_BYTELEN(h));
p_start = DUK_HSTRING_GET_DATA(h);
p_end = p_start + DUK_HSTRING_GET_BYTELEN(h);
p = p_start + boff;
DUK_DDD(DUK_DDDPRINT("p_start=%p, p_end=%p, p=%p", (const void *) p_start, (const void *) p_end, (const void *) p));
/* For invalid UTF-8 (never happens for standard ECMAScript strings)
* return U+FFFD replacement character.
*/
if (duk_unicode_decode_xutf8(thr, &p, p_start, p_end, &cp1)) {
if (surrogate_aware && cp1 >= 0xd800UL && cp1 <= 0xdbffUL) {
/* The decode helper is memory safe even if 'cp1' was
* decoded at the end of the string and 'p' is no longer
* within string memory range.
*/
cp2 = 0; /* If call fails, this is left untouched and won't match cp2 check. */
(void) duk_unicode_decode_xutf8(thr, &p, p_start, p_end, &cp2);
if (cp2 >= 0xdc00UL && cp2 <= 0xdfffUL) {
cp1 = (duk_ucodepoint_t) (((cp1 - 0xd800UL) << 10) + (cp2 - 0xdc00UL) + 0x10000UL);
}
}
} else {
cp1 = DUK_UNICODE_CP_REPLACEMENT_CHARACTER;
}
return cp1;
}
/*
* duk_hstring charlen, when lazy charlen disabled
*/
#if !defined(DUK_USE_HSTRING_LAZY_CLEN)
#if !defined(DUK_USE_HSTRING_CLEN)
#error non-lazy duk_hstring charlen but DUK_USE_HSTRING_CLEN not set
#endif
DUK_INTERNAL void duk_hstring_init_charlen(duk_hstring *h) {
duk_uint32_t clen;
DUK_ASSERT(h != NULL);
DUK_ASSERT(!DUK_HSTRING_HAS_ASCII(h));
DUK_ASSERT(!DUK_HEAPHDR_HAS_READONLY((duk_heaphdr *) h));
clen = duk_unicode_unvalidated_utf8_length(DUK_HSTRING_GET_DATA(h), DUK_HSTRING_GET_BYTELEN(h));
#if defined(DUK_USE_STRLEN16)
DUK_ASSERT(clen <= 0xffffUL); /* Bytelength checked during interning. */
h->clen16 = (duk_uint16_t) clen;
#else
h->clen = (duk_uint32_t) clen;
#endif
if (DUK_LIKELY(clen == DUK_HSTRING_GET_BYTELEN(h))) {
DUK_HSTRING_SET_ASCII(h);
}
}
DUK_INTERNAL DUK_HOT duk_size_t duk_hstring_get_charlen(duk_hstring *h) {
#if defined(DUK_USE_STRLEN16)
return h->clen16;
#else
return h->clen;
#endif
}
#endif /* !DUK_USE_HSTRING_LAZY_CLEN */
/*
* duk_hstring charlen, when lazy charlen enabled
*/
#if defined(DUK_USE_HSTRING_LAZY_CLEN)
#if defined(DUK_USE_HSTRING_CLEN)
DUK_LOCAL DUK_COLD duk_size_t duk__hstring_get_charlen_slowpath(duk_hstring *h) {
duk_size_t res;
DUK_ASSERT(h->clen == 0); /* Checked by caller. */
#if defined(DUK_USE_ROM_STRINGS)
/* ROM strings have precomputed clen, but if the computed clen is zero
* we can still come here and can't write anything.
*/
if (DUK_HEAPHDR_HAS_READONLY((duk_heaphdr *) h)) {
return 0;
}
#endif
res = duk_unicode_unvalidated_utf8_length(DUK_HSTRING_GET_DATA(h), DUK_HSTRING_GET_BYTELEN(h));
#if defined(DUK_USE_STRLEN16)
DUK_ASSERT(res <= 0xffffUL); /* Bytelength checked during interning. */
h->clen16 = (duk_uint16_t) res;
#else
h->clen = (duk_uint32_t) res;
#endif
if (DUK_LIKELY(res == DUK_HSTRING_GET_BYTELEN(h))) {
DUK_HSTRING_SET_ASCII(h);
}
return res;
}
#else /* DUK_USE_HSTRING_CLEN */
DUK_LOCAL duk_size_t duk__hstring_get_charlen_slowpath(duk_hstring *h) {
if (DUK_LIKELY(DUK_HSTRING_HAS_ASCII(h))) {
/* Most practical strings will go here. */
return DUK_HSTRING_GET_BYTELEN(h);
} else {
/* ASCII flag is lazy, so set it here. */
duk_size_t res;
/* XXX: here we could use the strcache to speed up the
* computation (matters for 'i < str.length' loops).
*/
res = duk_unicode_unvalidated_utf8_length(DUK_HSTRING_GET_DATA(h), DUK_HSTRING_GET_BYTELEN(h));
#if defined(DUK_USE_ROM_STRINGS)
if (DUK_HEAPHDR_HAS_READONLY((duk_heaphdr *) h)) {
/* For ROM strings, can't write anything; ASCII flag
* is preset so we don't need to update it.
*/
return res;
}
#endif
if (DUK_LIKELY(res == DUK_HSTRING_GET_BYTELEN(h))) {
DUK_HSTRING_SET_ASCII(h);
}
return res;
}
}
#endif /* DUK_USE_HSTRING_CLEN */
#if defined(DUK_USE_HSTRING_CLEN)
DUK_INTERNAL DUK_HOT duk_size_t duk_hstring_get_charlen(duk_hstring *h) {
#if defined(DUK_USE_STRLEN16)
if (DUK_LIKELY(h->clen16 != 0)) {
return h->clen16;
}
#else
if (DUK_LIKELY(h->clen != 0)) {
return h->clen;
}
#endif
return duk__hstring_get_charlen_slowpath(h);
}
#else /* DUK_USE_HSTRING_CLEN */
DUK_INTERNAL DUK_HOT duk_size_t duk_hstring_get_charlen(duk_hstring *h) {
/* Always use slow path. */
return duk__hstring_get_charlen_slowpath(h);
}
#endif /* DUK_USE_HSTRING_CLEN */
#endif /* DUK_USE_HSTRING_LAZY_CLEN */
/*
* Compare duk_hstring to an ASCII cstring.
*/
DUK_INTERNAL duk_bool_t duk_hstring_equals_ascii_cstring(duk_hstring *h, const char *cstr) {
duk_size_t len;
DUK_ASSERT(h != NULL);
DUK_ASSERT(cstr != NULL);
len = DUK_STRLEN(cstr);
if (len != DUK_HSTRING_GET_BYTELEN(h)) {
return 0;
}
if (duk_memcmp((const void *) cstr, (const void *) DUK_HSTRING_GET_DATA(h), len) == 0) {
return 1;
}
return 0;
}
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