XeNote/.yarn/unplugged/nan-npm-2.14.2-e3ede8ce5d/node_modules/nan/nan_string_bytes.h
canburaks b23e3ff508 ...
2021-05-17 04:16:19 +03:00

306 lines
7.9 KiB
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// Copyright Joyent, Inc. and other Node contributors.
//
// Permission is hereby granted, free of charge, to any person obtaining a
// copy of this software and associated documentation files (the
// "Software"), to deal in the Software without restriction, including
// without limitation the rights to use, copy, modify, merge, publish,
// distribute, sublicense, and/or sell copies of the Software, and to permit
// persons to whom the Software is furnished to do so, subject to the
// following conditions:
//
// The above copyright notice and this permission notice shall be included
// in all copies or substantial portions of the Software.
//
// THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS
// OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
// MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN
// NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM,
// DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR
// OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE
// USE OR OTHER DEALINGS IN THE SOFTWARE.
#ifndef NAN_STRING_BYTES_H_
#define NAN_STRING_BYTES_H_
// Decodes a v8::Local<v8::String> or Buffer to a raw char*
namespace imp {
using v8::Local;
using v8::Object;
using v8::String;
using v8::Value;
//// Base 64 ////
#define base64_encoded_size(size) ((size + 2 - ((size + 2) % 3)) / 3 * 4)
//// HEX ////
static bool contains_non_ascii_slow(const char* buf, size_t len) {
for (size_t i = 0; i < len; ++i) {
if (buf[i] & 0x80) return true;
}
return false;
}
static bool contains_non_ascii(const char* src, size_t len) {
if (len < 16) {
return contains_non_ascii_slow(src, len);
}
const unsigned bytes_per_word = sizeof(void*);
const unsigned align_mask = bytes_per_word - 1;
const unsigned unaligned = reinterpret_cast<uintptr_t>(src) & align_mask;
if (unaligned > 0) {
const unsigned n = bytes_per_word - unaligned;
if (contains_non_ascii_slow(src, n)) return true;
src += n;
len -= n;
}
#if defined(__x86_64__) || defined(_WIN64)
const uintptr_t mask = 0x8080808080808080ll;
#else
const uintptr_t mask = 0x80808080l;
#endif
const uintptr_t* srcw = reinterpret_cast<const uintptr_t*>(src);
for (size_t i = 0, n = len / bytes_per_word; i < n; ++i) {
if (srcw[i] & mask) return true;
}
const unsigned remainder = len & align_mask;
if (remainder > 0) {
const size_t offset = len - remainder;
if (contains_non_ascii_slow(src + offset, remainder)) return true;
}
return false;
}
static void force_ascii_slow(const char* src, char* dst, size_t len) {
for (size_t i = 0; i < len; ++i) {
dst[i] = src[i] & 0x7f;
}
}
static void force_ascii(const char* src, char* dst, size_t len) {
if (len < 16) {
force_ascii_slow(src, dst, len);
return;
}
const unsigned bytes_per_word = sizeof(void*);
const unsigned align_mask = bytes_per_word - 1;
const unsigned src_unalign = reinterpret_cast<uintptr_t>(src) & align_mask;
const unsigned dst_unalign = reinterpret_cast<uintptr_t>(dst) & align_mask;
if (src_unalign > 0) {
if (src_unalign == dst_unalign) {
const unsigned unalign = bytes_per_word - src_unalign;
force_ascii_slow(src, dst, unalign);
src += unalign;
dst += unalign;
len -= src_unalign;
} else {
force_ascii_slow(src, dst, len);
return;
}
}
#if defined(__x86_64__) || defined(_WIN64)
const uintptr_t mask = ~0x8080808080808080ll;
#else
const uintptr_t mask = ~0x80808080l;
#endif
const uintptr_t* srcw = reinterpret_cast<const uintptr_t*>(src);
uintptr_t* dstw = reinterpret_cast<uintptr_t*>(dst);
for (size_t i = 0, n = len / bytes_per_word; i < n; ++i) {
dstw[i] = srcw[i] & mask;
}
const unsigned remainder = len & align_mask;
if (remainder > 0) {
const size_t offset = len - remainder;
force_ascii_slow(src + offset, dst + offset, remainder);
}
}
static size_t base64_encode(const char* src,
size_t slen,
char* dst,
size_t dlen) {
// We know how much we'll write, just make sure that there's space.
assert(dlen >= base64_encoded_size(slen) &&
"not enough space provided for base64 encode");
dlen = base64_encoded_size(slen);
unsigned a;
unsigned b;
unsigned c;
unsigned i;
unsigned k;
unsigned n;
static const char table[] = "ABCDEFGHIJKLMNOPQRSTUVWXYZ"
"abcdefghijklmnopqrstuvwxyz"
"0123456789+/";
i = 0;
k = 0;
n = slen / 3 * 3;
while (i < n) {
a = src[i + 0] & 0xff;
b = src[i + 1] & 0xff;
c = src[i + 2] & 0xff;
dst[k + 0] = table[a >> 2];
dst[k + 1] = table[((a & 3) << 4) | (b >> 4)];
dst[k + 2] = table[((b & 0x0f) << 2) | (c >> 6)];
dst[k + 3] = table[c & 0x3f];
i += 3;
k += 4;
}
if (n != slen) {
switch (slen - n) {
case 1:
a = src[i + 0] & 0xff;
dst[k + 0] = table[a >> 2];
dst[k + 1] = table[(a & 3) << 4];
dst[k + 2] = '=';
dst[k + 3] = '=';
break;
case 2:
a = src[i + 0] & 0xff;
b = src[i + 1] & 0xff;
dst[k + 0] = table[a >> 2];
dst[k + 1] = table[((a & 3) << 4) | (b >> 4)];
dst[k + 2] = table[(b & 0x0f) << 2];
dst[k + 3] = '=';
break;
}
}
return dlen;
}
static size_t hex_encode(const char* src, size_t slen, char* dst, size_t dlen) {
// We know how much we'll write, just make sure that there's space.
assert(dlen >= slen * 2 &&
"not enough space provided for hex encode");
dlen = slen * 2;
for (uint32_t i = 0, k = 0; k < dlen; i += 1, k += 2) {
static const char hex[] = "0123456789abcdef";
uint8_t val = static_cast<uint8_t>(src[i]);
dst[k + 0] = hex[val >> 4];
dst[k + 1] = hex[val & 15];
}
return dlen;
}
static Local<Value> Encode(const char* buf,
size_t buflen,
enum Encoding encoding) {
assert(buflen <= node::Buffer::kMaxLength);
if (!buflen && encoding != BUFFER)
return New("").ToLocalChecked();
Local<String> val;
switch (encoding) {
case BUFFER:
return CopyBuffer(buf, buflen).ToLocalChecked();
case ASCII:
if (contains_non_ascii(buf, buflen)) {
char* out = new char[buflen];
force_ascii(buf, out, buflen);
val = New<String>(out, buflen).ToLocalChecked();
delete[] out;
} else {
val = New<String>(buf, buflen).ToLocalChecked();
}
break;
case UTF8:
val = New<String>(buf, buflen).ToLocalChecked();
break;
case BINARY: {
// TODO(isaacs) use ExternalTwoByteString?
const unsigned char *cbuf = reinterpret_cast<const unsigned char*>(buf);
uint16_t * twobytebuf = new uint16_t[buflen];
for (size_t i = 0; i < buflen; i++) {
// XXX is the following line platform independent?
twobytebuf[i] = cbuf[i];
}
val = New<String>(twobytebuf, buflen).ToLocalChecked();
delete[] twobytebuf;
break;
}
case BASE64: {
size_t dlen = base64_encoded_size(buflen);
char* dst = new char[dlen];
size_t written = base64_encode(buf, buflen, dst, dlen);
assert(written == dlen);
val = New<String>(dst, dlen).ToLocalChecked();
delete[] dst;
break;
}
case UCS2: {
const uint16_t* data = reinterpret_cast<const uint16_t*>(buf);
val = New<String>(data, buflen / 2).ToLocalChecked();
break;
}
case HEX: {
size_t dlen = buflen * 2;
char* dst = new char[dlen];
size_t written = hex_encode(buf, buflen, dst, dlen);
assert(written == dlen);
val = New<String>(dst, dlen).ToLocalChecked();
delete[] dst;
break;
}
default:
assert(0 && "unknown encoding");
break;
}
return val;
}
#undef base64_encoded_size
} // end of namespace imp
#endif // NAN_STRING_BYTES_H_