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Diffstat (limited to '')
| -rw-r--r-- | src/civetweb/src/third_party/duktape-1.8.0/src-separate/duk_hstring.h | 219 |
1 files changed, 219 insertions, 0 deletions
diff --git a/src/civetweb/src/third_party/duktape-1.8.0/src-separate/duk_hstring.h b/src/civetweb/src/third_party/duktape-1.8.0/src-separate/duk_hstring.h new file mode 100644 index 000000000..f80ec3497 --- /dev/null +++ b/src/civetweb/src/third_party/duktape-1.8.0/src-separate/duk_hstring.h @@ -0,0 +1,219 @@ +/* + * Heap string representation. + * + * Strings are byte sequences ordinarily stored in extended UTF-8 format, + * allowing values larger than the official UTF-8 range (used internally) + * and also allowing UTF-8 encoding of surrogate pairs (CESU-8 format). + * Strings may also be invalid UTF-8 altogether which is the case e.g. with + * strings used as internal property names and raw buffers converted to + * strings. In such cases the 'clen' field contains an inaccurate value. + * + * Ecmascript requires support for 32-bit long strings. However, since each + * 16-bit codepoint can take 3 bytes in CESU-8, this representation can only + * support about 1.4G codepoint long strings in extreme cases. This is not + * really a practical issue. + */ + +#ifndef DUK_HSTRING_H_INCLUDED +#define DUK_HSTRING_H_INCLUDED + +/* Impose a maximum string length for now. Restricted artificially to + * ensure adding a heap header length won't overflow size_t. The limit + * should be synchronized with DUK_HBUFFER_MAX_BYTELEN. + * + * E5.1 makes provisions to support strings longer than 4G characters. + * This limit should be eliminated on 64-bit platforms (and increased + * closer to maximum support on 32-bit platforms). + */ + +#if defined(DUK_USE_STRLEN16) +#define DUK_HSTRING_MAX_BYTELEN (0x0000ffffUL) +#else +#define DUK_HSTRING_MAX_BYTELEN (0x7fffffffUL) +#endif + +/* XXX: could add flags for "is valid CESU-8" (Ecmascript compatible strings), + * "is valid UTF-8", "is valid extended UTF-8" (internal strings are not, + * regexp bytecode is), and "contains non-BMP characters". These are not + * needed right now. + */ + +#define DUK_HSTRING_FLAG_ASCII DUK_HEAPHDR_USER_FLAG(0) /* string is ASCII, clen == blen */ +#define DUK_HSTRING_FLAG_ARRIDX DUK_HEAPHDR_USER_FLAG(1) /* string is a valid array index */ +#define DUK_HSTRING_FLAG_INTERNAL DUK_HEAPHDR_USER_FLAG(2) /* string is internal */ +#define DUK_HSTRING_FLAG_RESERVED_WORD DUK_HEAPHDR_USER_FLAG(3) /* string is a reserved word (non-strict) */ +#define DUK_HSTRING_FLAG_STRICT_RESERVED_WORD DUK_HEAPHDR_USER_FLAG(4) /* string is a reserved word (strict) */ +#define DUK_HSTRING_FLAG_EVAL_OR_ARGUMENTS DUK_HEAPHDR_USER_FLAG(5) /* string is 'eval' or 'arguments' */ +#define DUK_HSTRING_FLAG_EXTDATA DUK_HEAPHDR_USER_FLAG(6) /* string data is external (duk_hstring_external) */ + +#define DUK_HSTRING_HAS_ASCII(x) DUK_HEAPHDR_CHECK_FLAG_BITS(&(x)->hdr, DUK_HSTRING_FLAG_ASCII) +#define DUK_HSTRING_HAS_ARRIDX(x) DUK_HEAPHDR_CHECK_FLAG_BITS(&(x)->hdr, DUK_HSTRING_FLAG_ARRIDX) +#define DUK_HSTRING_HAS_INTERNAL(x) DUK_HEAPHDR_CHECK_FLAG_BITS(&(x)->hdr, DUK_HSTRING_FLAG_INTERNAL) +#define DUK_HSTRING_HAS_RESERVED_WORD(x) DUK_HEAPHDR_CHECK_FLAG_BITS(&(x)->hdr, DUK_HSTRING_FLAG_RESERVED_WORD) +#define DUK_HSTRING_HAS_STRICT_RESERVED_WORD(x) DUK_HEAPHDR_CHECK_FLAG_BITS(&(x)->hdr, DUK_HSTRING_FLAG_STRICT_RESERVED_WORD) +#define DUK_HSTRING_HAS_EVAL_OR_ARGUMENTS(x) DUK_HEAPHDR_CHECK_FLAG_BITS(&(x)->hdr, DUK_HSTRING_FLAG_EVAL_OR_ARGUMENTS) +#define DUK_HSTRING_HAS_EXTDATA(x) DUK_HEAPHDR_CHECK_FLAG_BITS(&(x)->hdr, DUK_HSTRING_FLAG_EXTDATA) + +#define DUK_HSTRING_SET_ASCII(x) DUK_HEAPHDR_SET_FLAG_BITS(&(x)->hdr, DUK_HSTRING_FLAG_ASCII) +#define DUK_HSTRING_SET_ARRIDX(x) DUK_HEAPHDR_SET_FLAG_BITS(&(x)->hdr, DUK_HSTRING_FLAG_ARRIDX) +#define DUK_HSTRING_SET_INTERNAL(x) DUK_HEAPHDR_SET_FLAG_BITS(&(x)->hdr, DUK_HSTRING_FLAG_INTERNAL) +#define DUK_HSTRING_SET_RESERVED_WORD(x) DUK_HEAPHDR_SET_FLAG_BITS(&(x)->hdr, DUK_HSTRING_FLAG_RESERVED_WORD) +#define DUK_HSTRING_SET_STRICT_RESERVED_WORD(x) DUK_HEAPHDR_SET_FLAG_BITS(&(x)->hdr, DUK_HSTRING_FLAG_STRICT_RESERVED_WORD) +#define DUK_HSTRING_SET_EVAL_OR_ARGUMENTS(x) DUK_HEAPHDR_SET_FLAG_BITS(&(x)->hdr, DUK_HSTRING_FLAG_EVAL_OR_ARGUMENTS) +#define DUK_HSTRING_SET_EXTDATA(x) DUK_HEAPHDR_SET_FLAG_BITS(&(x)->hdr, DUK_HSTRING_FLAG_EXTDATA) + +#define DUK_HSTRING_CLEAR_ASCII(x) DUK_HEAPHDR_CLEAR_FLAG_BITS(&(x)->hdr, DUK_HSTRING_FLAG_ASCII) +#define DUK_HSTRING_CLEAR_ARRIDX(x) DUK_HEAPHDR_CLEAR_FLAG_BITS(&(x)->hdr, DUK_HSTRING_FLAG_ARRIDX) +#define DUK_HSTRING_CLEAR_INTERNAL(x) DUK_HEAPHDR_CLEAR_FLAG_BITS(&(x)->hdr, DUK_HSTRING_FLAG_INTERNAL) +#define DUK_HSTRING_CLEAR_RESERVED_WORD(x) DUK_HEAPHDR_CLEAR_FLAG_BITS(&(x)->hdr, DUK_HSTRING_FLAG_RESERVED_WORD) +#define DUK_HSTRING_CLEAR_STRICT_RESERVED_WORD(x) DUK_HEAPHDR_CLEAR_FLAG_BITS(&(x)->hdr, DUK_HSTRING_FLAG_STRICT_RESERVED_WORD) +#define DUK_HSTRING_CLEAR_EVAL_OR_ARGUMENTS(x) DUK_HEAPHDR_CLEAR_FLAG_BITS(&(x)->hdr, DUK_HSTRING_FLAG_EVAL_OR_ARGUMENTS) +#define DUK_HSTRING_CLEAR_EXTDATA(x) DUK_HEAPHDR_CLEAR_FLAG_BITS(&(x)->hdr, DUK_HSTRING_FLAG_EXTDATA) + +#if 0 /* Slightly smaller code without explicit flag, but explicit flag + * is very useful when 'clen' is dropped. + */ +#define DUK_HSTRING_IS_ASCII(x) (DUK_HSTRING_GET_BYTELEN((x)) == DUK_HSTRING_GET_CHARLEN((x))) +#endif +#define DUK_HSTRING_IS_ASCII(x) DUK_HSTRING_HAS_ASCII((x)) +#define DUK_HSTRING_IS_EMPTY(x) (DUK_HSTRING_GET_BYTELEN((x)) == 0) + +#if defined(DUK_USE_STRHASH16) +#define DUK_HSTRING_GET_HASH(x) ((x)->hdr.h_flags >> 16) +#define DUK_HSTRING_SET_HASH(x,v) do { \ + (x)->hdr.h_flags = ((x)->hdr.h_flags & 0x0000ffffUL) | ((v) << 16); \ + } while (0) +#else +#define DUK_HSTRING_GET_HASH(x) ((x)->hash) +#define DUK_HSTRING_SET_HASH(x,v) do { \ + (x)->hash = (v); \ + } while (0) +#endif + +#if defined(DUK_USE_STRLEN16) +#define DUK_HSTRING_GET_BYTELEN(x) ((x)->hdr.h_strextra16) +#define DUK_HSTRING_SET_BYTELEN(x,v) do { \ + (x)->hdr.h_strextra16 = (v); \ + } while (0) +#if defined(DUK_USE_HSTRING_CLEN) +#define DUK_HSTRING_GET_CHARLEN(x) ((x)->clen16) +#define DUK_HSTRING_SET_CHARLEN(x,v) do { \ + (x)->clen16 = (v); \ + } while (0) +#else +#define DUK_HSTRING_GET_CHARLEN(x) duk_hstring_get_charlen((x)) +#define DUK_HSTRING_SET_CHARLEN(x,v) do { \ + DUK_ASSERT(0); /* should never be called */ \ + } while (0) +#endif +#else +#define DUK_HSTRING_GET_BYTELEN(x) ((x)->blen) +#define DUK_HSTRING_SET_BYTELEN(x,v) do { \ + (x)->blen = (v); \ + } while (0) +#define DUK_HSTRING_GET_CHARLEN(x) ((x)->clen) +#define DUK_HSTRING_SET_CHARLEN(x,v) do { \ + (x)->clen = (v); \ + } while (0) +#endif + +#if defined(DUK_USE_HSTRING_EXTDATA) +#define DUK_HSTRING_GET_EXTDATA(x) \ + ((x)->extdata) +#define DUK_HSTRING_GET_DATA(x) \ + (DUK_HSTRING_HAS_EXTDATA((x)) ? \ + DUK_HSTRING_GET_EXTDATA((const duk_hstring_external *) (x)) : ((const duk_uint8_t *) ((x) + 1))) +#else +#define DUK_HSTRING_GET_DATA(x) \ + ((const duk_uint8_t *) ((x) + 1)) +#endif + +#define DUK_HSTRING_GET_DATA_END(x) \ + (DUK_HSTRING_GET_DATA((x)) + (x)->blen) + +/* marker value; in E5 2^32-1 is not a valid array index (2^32-2 is highest valid) */ +#define DUK_HSTRING_NO_ARRAY_INDEX (0xffffffffUL) + +/* get array index related to string (or return DUK_HSTRING_NO_ARRAY_INDEX); + * avoids helper call if string has no array index value. + */ +#define DUK_HSTRING_GET_ARRIDX_FAST(h) \ + (DUK_HSTRING_HAS_ARRIDX((h)) ? duk_js_to_arrayindex_string_helper((h)) : DUK_HSTRING_NO_ARRAY_INDEX) + +/* slower but more compact variant */ +#define DUK_HSTRING_GET_ARRIDX_SLOW(h) \ + (duk_js_to_arrayindex_string_helper((h))) + +/* + * Misc + */ + +struct duk_hstring { + /* Smaller heaphdr than for other objects, because strings are held + * in string intern table which requires no link pointers. Much of + * the 32-bit flags field is unused by flags, so we can stuff a 16-bit + * field in there. + */ + duk_heaphdr_string hdr; + + /* Note: we could try to stuff a partial hash (e.g. 16 bits) into the + * shared heap header. Good hashing needs more hash bits though. + */ + + /* string hash */ +#if defined(DUK_USE_STRHASH16) + /* If 16-bit hash is in use, stuff it into duk_heaphdr_string flags. */ +#else + duk_uint32_t hash; +#endif + + /* length in bytes (not counting NUL term) */ +#if defined(DUK_USE_STRLEN16) + /* placed in duk_heaphdr_string */ +#else + duk_uint32_t blen; +#endif + + /* length in codepoints (must be E5 compatible) */ +#if defined(DUK_USE_STRLEN16) +#if defined(DUK_USE_HSTRING_CLEN) + duk_uint16_t clen16; +#else + /* computed live */ +#endif +#else + duk_uint32_t clen; +#endif + + /* + * String value of 'blen+1' bytes follows (+1 for NUL termination + * convenience for C API). No alignment needs to be guaranteed + * for strings, but fields above should guarantee alignment-by-4 + * (but not alignment-by-8). + */ +}; + +/* The external string struct is defined even when the feature is inactive. */ +struct duk_hstring_external { + duk_hstring str; + + /* + * For an external string, the NUL-terminated string data is stored + * externally. The user must guarantee that data behind this pointer + * doesn't change while it's used. + */ + + const duk_uint8_t *extdata; +}; + +/* + * Prototypes + */ + +DUK_INTERNAL_DECL duk_ucodepoint_t duk_hstring_char_code_at_raw(duk_hthread *thr, duk_hstring *h, duk_uint_t pos); + +#if !defined(DUK_USE_HSTRING_CLEN) +DUK_INTERNAL_DECL duk_size_t duk_hstring_get_charlen(duk_hstring *h); +#endif + +#endif /* DUK_HSTRING_H_INCLUDED */ |