GCC Code Coverage Report
Directory: ./ Exec Total Coverage
File: string_bytes.cc Lines: 277 339 81.7 %
Date: 2022-06-21 04:15:54 Branches: 118 175 67.4 %

Line Branch Exec Source
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// Copyright Joyent, Inc. and other Node contributors.
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//
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// Permission is hereby granted, free of charge, to any person obtaining a
4
// copy of this software and associated documentation files (the
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// "Software"), to deal in the Software without restriction, including
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// without limitation the rights to use, copy, modify, merge, publish,
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// distribute, sublicense, and/or sell copies of the Software, and to permit
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// persons to whom the Software is furnished to do so, subject to the
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// following conditions:
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//
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// The above copyright notice and this permission notice shall be included
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// in all copies or substantial portions of the Software.
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//
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// THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS
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// OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
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// MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN
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// NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM,
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// DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR
19
// OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE
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// USE OR OTHER DEALINGS IN THE SOFTWARE.
21
22
#include "string_bytes.h"
23
24
#include "base64-inl.h"
25
#include "env-inl.h"
26
#include "node_buffer.h"
27
#include "node_errors.h"
28
#include "util.h"
29
30
#include <climits>
31
#include <cstring>  // memcpy
32
33
#include <algorithm>
34
35
// When creating strings >= this length v8's gc spins up and consumes
36
// most of the execution time. For these cases it's more performant to
37
// use external string resources.
38
#define EXTERN_APEX 0xFBEE9
39
40
namespace node {
41
42
using v8::HandleScope;
43
using v8::Isolate;
44
using v8::Just;
45
using v8::Local;
46
using v8::Maybe;
47
using v8::MaybeLocal;
48
using v8::Nothing;
49
using v8::String;
50
using v8::Value;
51
52
namespace {
53
54
template <typename ResourceType, typename TypeName>
55
class ExternString: public ResourceType {
56
 public:
57
128
  ~ExternString() override {
58
64
    free(const_cast<TypeName*>(data_));
59
64
    isolate()->AdjustAmountOfExternalAllocatedMemory(-byte_length());
60
192
  }
61
62
178
  const TypeName* data() const override {
63
178
    return data_;
64
  }
65
66
408
  size_t length() const override {
67
408
    return length_;
68
  }
69
70
128
  int64_t byte_length() const {
71
128
    return length() * sizeof(*data());
72
  }
73
74
19928
  static MaybeLocal<Value> NewFromCopy(Isolate* isolate,
75
                                       const TypeName* data,
76
                                       size_t length,
77
                                       Local<Value>* error) {
78
19928
    if (length == 0)
79
4
      return String::Empty(isolate);
80
81
19924
    if (length < EXTERN_APEX)
82
19896
      return NewSimpleFromCopy(isolate, data, length, error);
83
84
28
    TypeName* new_data = node::UncheckedMalloc<TypeName>(length);
85
28
    if (new_data == nullptr) {
86
      *error = node::ERR_MEMORY_ALLOCATION_FAILED(isolate);
87
      return MaybeLocal<Value>();
88
    }
89
28
    memcpy(new_data, data, length * sizeof(*new_data));
90
91
28
    return ExternString<ResourceType, TypeName>::New(isolate,
92
                                                     new_data,
93
                                                     length,
94
28
                                                     error);
95
  }
96
97
  // uses "data" for external resource, and will be free'd on gc
98
29000
  static MaybeLocal<Value> New(Isolate* isolate,
99
                               TypeName* data,
100
                               size_t length,
101
                               Local<Value>* error) {
102
29000
    if (length == 0)
103
      return String::Empty(isolate);
104
105
29000
    if (length < EXTERN_APEX) {
106
28936
      MaybeLocal<Value> str = NewSimpleFromCopy(isolate, data, length, error);
107
28936
      free(data);
108
28936
      return str;
109
    }
110
111
64
    ExternString* h_str = new ExternString<ResourceType, TypeName>(isolate,
112
                                                                   data,
113
                                                                   length);
114
64
    MaybeLocal<Value> str = NewExternal(isolate, h_str);
115
64
    isolate->AdjustAmountOfExternalAllocatedMemory(h_str->byte_length());
116
117
64
    if (str.IsEmpty()) {
118
10
      delete h_str;
119
10
      *error = node::ERR_STRING_TOO_LONG(isolate);
120
10
      return MaybeLocal<Value>();
121
    }
122
123
54
    return str.ToLocalChecked();
124
  }
125
126
64
  inline Isolate* isolate() const { return isolate_; }
127
128
 private:
129
64
  ExternString(Isolate* isolate, const TypeName* data, size_t length)
130
64
    : isolate_(isolate), data_(data), length_(length) { }
131
  static MaybeLocal<Value> NewExternal(Isolate* isolate,
132
                                       ExternString* h_str);
133
134
  // This method does not actually create ExternString instances.
135
  static MaybeLocal<Value> NewSimpleFromCopy(Isolate* isolate,
136
                                             const TypeName* data,
137
                                             size_t length,
138
                                             Local<Value>* error);
139
140
  Isolate* isolate_;
141
  const TypeName* data_;
142
  size_t length_;
143
};
144
145
146
typedef ExternString<String::ExternalOneByteStringResource,
147
                     char> ExternOneByteString;
148
typedef ExternString<String::ExternalStringResource,
149
                     uint16_t> ExternTwoByteString;
150
151
152
template <>
153
27
MaybeLocal<Value> ExternOneByteString::NewExternal(
154
    Isolate* isolate, ExternOneByteString* h_str) {
155
54
  return String::NewExternalOneByte(isolate, h_str).FromMaybe(Local<Value>());
156
}
157
158
159
template <>
160
5
MaybeLocal<Value> ExternTwoByteString::NewExternal(
161
    Isolate* isolate, ExternTwoByteString* h_str) {
162
10
  return String::NewExternalTwoByte(isolate, h_str).FromMaybe(Local<Value>());
163
}
164
165
template <>
166
19200
MaybeLocal<Value> ExternOneByteString::NewSimpleFromCopy(Isolate* isolate,
167
                                                         const char* data,
168
                                                         size_t length,
169
                                                         Local<Value>* error) {
170
  MaybeLocal<String> str =
171
      String::NewFromOneByte(isolate,
172
                             reinterpret_cast<const uint8_t*>(data),
173
                             v8::NewStringType::kNormal,
174
19200
                             length);
175
19200
  if (str.IsEmpty()) {
176
    *error = node::ERR_STRING_TOO_LONG(isolate);
177
    return MaybeLocal<Value>();
178
  }
179
19200
  return str.ToLocalChecked();
180
}
181
182
183
template <>
184
5216
MaybeLocal<Value> ExternTwoByteString::NewSimpleFromCopy(Isolate* isolate,
185
                                                         const uint16_t* data,
186
                                                         size_t length,
187
                                                         Local<Value>* error) {
188
  MaybeLocal<String> str =
189
      String::NewFromTwoByte(isolate,
190
                             data,
191
                             v8::NewStringType::kNormal,
192
5216
                             length);
193
5216
  if (str.IsEmpty()) {
194
    *error = node::ERR_STRING_TOO_LONG(isolate);
195
    return MaybeLocal<Value>();
196
  }
197
5216
  return str.ToLocalChecked();
198
}
199
200
}  // anonymous namespace
201
202
// supports regular and URL-safe base64
203
const int8_t unbase64_table[256] =
204
  { -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -2, -1, -1, -2, -1, -1,
205
    -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1,
206
    -2, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, 62, -1, 62, -1, 63,
207
    52, 53, 54, 55, 56, 57, 58, 59, 60, 61, -1, -1, -1, -1, -1, -1,
208
    -1,  0,  1,  2,  3,  4,  5,  6,  7,  8,  9, 10, 11, 12, 13, 14,
209
    15, 16, 17, 18, 19, 20, 21, 22, 23, 24, 25, -1, -1, -1, -1, 63,
210
    -1, 26, 27, 28, 29, 30, 31, 32, 33, 34, 35, 36, 37, 38, 39, 40,
211
    41, 42, 43, 44, 45, 46, 47, 48, 49, 50, 51, -1, -1, -1, -1, -1,
212
    -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1,
213
    -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1,
214
    -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1,
215
    -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1,
216
    -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1,
217
    -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1,
218
    -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1,
219
    -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1
220
  };
221
222
223
static const int8_t unhex_table[256] =
224
  { -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1,
225
    -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1,
226
    -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1,
227
     0,  1,  2,  3,  4,  5,  6,  7,  8,  9, -1, -1, -1, -1, -1, -1,
228
    -1, 10, 11, 12, 13, 14, 15, -1, -1, -1, -1, -1, -1, -1, -1, -1,
229
    -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1,
230
    -1, 10, 11, 12, 13, 14, 15, -1, -1, -1, -1, -1, -1, -1, -1, -1,
231
    -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1,
232
    -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1,
233
    -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1,
234
    -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1,
235
    -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1,
236
    -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1,
237
    -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1,
238
    -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1,
239
    -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1
240
  };
241
242
47466688
static inline unsigned unhex(uint8_t x) {
243
47466688
  return unhex_table[x];
244
}
245
246
template <typename TypeName>
247
9126
static size_t hex_decode(char* buf,
248
                         size_t len,
249
                         const TypeName* src,
250
                         const size_t srcLen) {
251
  size_t i;
252

47475796
  for (i = 0; i < len && i * 2 + 1 < srcLen; ++i) {
253
47466688
    unsigned a = unhex(static_cast<uint8_t>(src[i * 2 + 0]));
254
47466688
    unsigned b = unhex(static_cast<uint8_t>(src[i * 2 + 1]));
255

47466688
    if (!~a || !~b)
256
18
      return i;
257
47466670
    buf[i] = (a << 4) | b;
258
  }
259
260
9108
  return i;
261
}
262
263
159
size_t StringBytes::WriteUCS2(Isolate* isolate,
264
                              char* buf,
265
                              size_t buflen,
266
                              Local<String> str,
267
                              int flags,
268
                              size_t* chars_written) {
269
159
  uint16_t* const dst = reinterpret_cast<uint16_t*>(buf);
270
271
159
  size_t max_chars = buflen / sizeof(*dst);
272
159
  if (max_chars == 0) {
273
5
    return 0;
274
  }
275
276
154
  uint16_t* const aligned_dst = AlignUp(dst, sizeof(*dst));
277
  size_t nchars;
278
154
  if (aligned_dst == dst) {
279
149
    nchars = str->Write(isolate, dst, 0, max_chars, flags);
280
149
    *chars_written = nchars;
281
149
    return nchars * sizeof(*dst);
282
  }
283
284
5
  CHECK_EQ(reinterpret_cast<uintptr_t>(aligned_dst) % sizeof(*dst), 0);
285
286
  // Write all but the last char
287
5
  max_chars = std::min(max_chars, static_cast<size_t>(str->Length()));
288
5
  if (max_chars == 0) return 0;
289
5
  nchars = str->Write(isolate, aligned_dst, 0, max_chars - 1, flags);
290
5
  CHECK_EQ(nchars, max_chars - 1);
291
292
  // Shift everything to unaligned-left
293
5
  memmove(dst, aligned_dst, nchars * sizeof(*dst));
294
295
  // One more char to be written
296
  uint16_t last;
297
5
  CHECK_EQ(str->Write(isolate, &last, nchars, 1, flags), 1);
298
5
  memcpy(buf + nchars * sizeof(*dst), &last, sizeof(last));
299
5
  nchars++;
300
301
5
  *chars_written = nchars;
302
5
  return nchars * sizeof(*dst);
303
}
304
305
306
429712
size_t StringBytes::Write(Isolate* isolate,
307
                          char* buf,
308
                          size_t buflen,
309
                          Local<Value> val,
310
                          enum encoding encoding,
311
                          int* chars_written) {
312
429712
  HandleScope scope(isolate);
313
  size_t nbytes;
314
  int nchars;
315
316
429712
  if (chars_written == nullptr)
317
429712
    chars_written = &nchars;
318
319
859424
  CHECK(val->IsString() == true);
320
429712
  Local<String> str = val.As<String>();
321
322
429712
  int flags = String::HINT_MANY_WRITES_EXPECTED |
323
              String::NO_NULL_TERMINATION |
324
              String::REPLACE_INVALID_UTF8;
325
326

429712
  switch (encoding) {
327
41031
    case ASCII:
328
    case LATIN1:
329
41031
      if (str->IsExternalOneByte()) {
330
1
        auto ext = str->GetExternalOneByteStringResource();
331
1
        nbytes = std::min(buflen, ext->length());
332
1
        memcpy(buf, ext->data(), nbytes);
333
      } else {
334
41030
        uint8_t* const dst = reinterpret_cast<uint8_t*>(buf);
335
41030
        nbytes = str->WriteOneByte(isolate, dst, 0, buflen, flags);
336
      }
337
41031
      *chars_written = nbytes;
338
41031
      break;
339
340
379962
    case BUFFER:
341
    case UTF8:
342
379962
      nbytes = str->WriteUtf8(isolate, buf, buflen, chars_written, flags);
343
379962
      break;
344
345
159
    case UCS2: {
346
      size_t nchars;
347
348
159
      nbytes = WriteUCS2(isolate, buf, buflen, str, flags, &nchars);
349
159
      *chars_written = static_cast<int>(nchars);
350
351
      // Node's "ucs2" encoding wants LE character data stored in
352
      // the Buffer, so we need to reorder on BE platforms.  See
353
      // https://nodejs.org/api/buffer.html regarding Node's "ucs2"
354
      // encoding specification
355
159
      if (IsBigEndian())
356
        SwapBytes16(buf, nbytes);
357
358
159
      break;
359
    }
360
361
3997
    case BASE64URL:
362
      // Fall through
363
    case BASE64:
364
3997
      if (str->IsExternalOneByte()) {
365
4
        auto ext = str->GetExternalOneByteStringResource();
366
4
        nbytes = base64_decode(buf, buflen, ext->data(), ext->length());
367
      } else {
368
7986
        String::Value value(isolate, str);
369
3993
        nbytes = base64_decode(buf, buflen, *value, value.length());
370
      }
371
3997
      *chars_written = nbytes;
372
3997
      break;
373
374
4563
    case HEX:
375
4563
      if (str->IsExternalOneByte()) {
376
22
        auto ext = str->GetExternalOneByteStringResource();
377
22
        nbytes = hex_decode(buf, buflen, ext->data(), ext->length());
378
      } else {
379
9082
        String::Value value(isolate, str);
380
4541
        nbytes = hex_decode(buf, buflen, *value, value.length());
381
      }
382
4563
      *chars_written = nbytes;
383
4563
      break;
384
385
    default:
386
      CHECK(0 && "unknown encoding");
387
      break;
388
  }
389
390
429712
  return nbytes;
391
}
392
393
394
// Quick and dirty size calculation
395
// Will always be at least big enough, but may have some extra
396
// UTF8 can be as much as 3x the size, Base64 can have 1-2 extra bytes
397
3697844
Maybe<size_t> StringBytes::StorageSize(Isolate* isolate,
398
                                       Local<Value> val,
399
                                       enum encoding encoding) {
400
7395688
  HandleScope scope(isolate);
401
3697844
  size_t data_size = 0;
402
3697844
  bool is_buffer = Buffer::HasInstance(val);
403
404

3697844
  if (is_buffer && (encoding == BUFFER || encoding == LATIN1)) {
405
    return Just(Buffer::Length(val));
406
  }
407
408
  Local<String> str;
409
7395688
  if (!val->ToString(isolate->GetCurrentContext()).ToLocal(&str))
410
    return Nothing<size_t>();
411
412

3697844
  switch (encoding) {
413
36812
    case ASCII:
414
    case LATIN1:
415
36812
      data_size = str->Length();
416
36812
      break;
417
418
3659858
    case BUFFER:
419
    case UTF8:
420
      // A single UCS2 codepoint never takes up more than 3 utf8 bytes.
421
      // It is an exercise for the caller to decide when a string is
422
      // long enough to justify calling Size() instead of StorageSize()
423
3659858
      data_size = 3 * str->Length();
424
3659858
      break;
425
426
6
    case UCS2:
427
6
      data_size = str->Length() * sizeof(uint16_t);
428
6
      break;
429
430
10
    case BASE64URL:
431
      // Fall through
432
    case BASE64:
433
10
      data_size = base64_decoded_size_fast(str->Length());
434
10
      break;
435
436
1158
    case HEX:
437

1158
      CHECK(str->Length() % 2 == 0 && "invalid hex string length");
438
1158
      data_size = str->Length() / 2;
439
1158
      break;
440
441
    default:
442
      CHECK(0 && "unknown encoding");
443
      break;
444
  }
445
446
3697844
  return Just(data_size);
447
}
448
449
4449
Maybe<size_t> StringBytes::Size(Isolate* isolate,
450
                                Local<Value> val,
451
                                enum encoding encoding) {
452
8898
  HandleScope scope(isolate);
453
454


4449
  if (Buffer::HasInstance(val) && (encoding == BUFFER || encoding == LATIN1))
455
    return Just(Buffer::Length(val));
456
457
  Local<String> str;
458
8898
  if (!val->ToString(isolate->GetCurrentContext()).ToLocal(&str))
459
    return Nothing<size_t>();
460
461

4449
  switch (encoding) {
462
17
    case ASCII:
463
    case LATIN1:
464
17
      return Just<size_t>(str->Length());
465
466
1101
    case BUFFER:
467
    case UTF8:
468
1101
      return Just<size_t>(str->Utf8Length(isolate));
469
470
101
    case UCS2:
471
101
      return Just(str->Length() * sizeof(uint16_t));
472
473
3194
    case BASE64URL:
474
      // Fall through
475
    case BASE64: {
476
3194
      String::Value value(isolate, str);
477
3194
      return Just(base64_decoded_size(*value, value.length()));
478
    }
479
480
36
    case HEX:
481
36
      return Just<size_t>(str->Length() / 2);
482
  }
483
484
  UNREACHABLE();
485
}
486
487
488
489
490
3476
static bool contains_non_ascii_slow(const char* buf, size_t len) {
491
16887
  for (size_t i = 0; i < len; ++i) {
492
13590
    if (buf[i] & 0x80)
493
179
      return true;
494
  }
495
3297
  return false;
496
}
497
498
499
3960
static bool contains_non_ascii(const char* src, size_t len) {
500
3960
  if (len < 16) {
501
3359
    return contains_non_ascii_slow(src, len);
502
  }
503
504
601
  const unsigned bytes_per_word = sizeof(uintptr_t);
505
601
  const unsigned align_mask = bytes_per_word - 1;
506
601
  const unsigned unaligned = reinterpret_cast<uintptr_t>(src) & align_mask;
507
508
601
  if (unaligned > 0) {
509
51
    const unsigned n = bytes_per_word - unaligned;
510
51
    if (contains_non_ascii_slow(src, n))
511
17
      return true;
512
34
    src += n;
513
34
    len -= n;
514
  }
515
516
517
#if defined(_WIN64) || defined(_LP64)
518
584
  const uintptr_t mask = 0x8080808080808080ll;
519
#else
520
  const uintptr_t mask = 0x80808080l;
521
#endif
522
523
584
  const uintptr_t* srcw = reinterpret_cast<const uintptr_t*>(src);
524
525
67112278
  for (size_t i = 0, n = len / bytes_per_word; i < n; ++i) {
526
67112210
    if (srcw[i] & mask)
527
516
      return true;
528
  }
529
530
68
  const unsigned remainder = len & align_mask;
531
68
  if (remainder > 0) {
532
66
    const size_t offset = len - remainder;
533
66
    if (contains_non_ascii_slow(src + offset, remainder))
534
      return true;
535
  }
536
537
68
  return false;
538
}
539
540
541
644
static void force_ascii_slow(const char* src, char* dst, size_t len) {
542
6125
  for (size_t i = 0; i < len; ++i) {
543
5481
    dst[i] = src[i] & 0x7f;
544
  }
545
644
}
546
547
548
695
static void force_ascii(const char* src, char* dst, size_t len) {
549
695
  if (len < 16) {
550
162
    force_ascii_slow(src, dst, len);
551
162
    return;
552
  }
553
554
533
  const unsigned bytes_per_word = sizeof(uintptr_t);
555
533
  const unsigned align_mask = bytes_per_word - 1;
556
533
  const unsigned src_unalign = reinterpret_cast<uintptr_t>(src) & align_mask;
557
533
  const unsigned dst_unalign = reinterpret_cast<uintptr_t>(dst) & align_mask;
558
559
533
  if (src_unalign > 0) {
560
50
    if (src_unalign == dst_unalign) {
561
      const unsigned unalign = bytes_per_word - src_unalign;
562
      force_ascii_slow(src, dst, unalign);
563
      src += unalign;
564
      dst += unalign;
565
      len -= src_unalign;
566
    } else {
567
50
      force_ascii_slow(src, dst, len);
568
50
      return;
569
    }
570
  }
571
572
#if defined(_WIN64) || defined(_LP64)
573
483
  const uintptr_t mask = ~0x8080808080808080ll;
574
#else
575
  const uintptr_t mask = ~0x80808080l;
576
#endif
577
578
483
  const uintptr_t* srcw = reinterpret_cast<const uintptr_t*>(src);
579
483
  uintptr_t* dstw = reinterpret_cast<uintptr_t*>(dst);
580
581
3398
  for (size_t i = 0, n = len / bytes_per_word; i < n; ++i) {
582
2915
    dstw[i] = srcw[i] & mask;
583
  }
584
585
483
  const unsigned remainder = len & align_mask;
586
483
  if (remainder > 0) {
587
432
    const size_t offset = len - remainder;
588
432
    force_ascii_slow(src + offset, dst + offset, remainder);
589
  }
590
}
591
592
593
7567
size_t StringBytes::hex_encode(
594
    const char* src,
595
    size_t slen,
596
    char* dst,
597
    size_t dlen) {
598
  // We know how much we'll write, just make sure that there's space.
599
7567
  CHECK(dlen >= slen * 2 &&
600
      "not enough space provided for hex encode");
601
602
7567
  dlen = slen * 2;
603
543510527
  for (uint32_t i = 0, k = 0; k < dlen; i += 1, k += 2) {
604
    static const char hex[] = "0123456789abcdef";
605
543502960
    uint8_t val = static_cast<uint8_t>(src[i]);
606
543502960
    dst[k + 0] = hex[val >> 4];
607
543502960
    dst[k + 1] = hex[val & 15];
608
  }
609
610
7567
  return dlen;
611
}
612
613
std::string StringBytes::hex_encode(const char* src, size_t slen) {
614
  size_t dlen = slen * 2;
615
  std::string dst(dlen, '\0');
616
  hex_encode(src, slen, &dst[0], dlen);
617
  return dst;
618
}
619
620
#define CHECK_BUFLEN_IN_RANGE(len)                                    \
621
  do {                                                                \
622
    if ((len) > Buffer::kMaxLength) {                                 \
623
      *error = node::ERR_BUFFER_TOO_LARGE(isolate);                   \
624
      return MaybeLocal<Value>();                                     \
625
    }                                                                 \
626
  } while (0)
627
628
629
920377
MaybeLocal<Value> StringBytes::Encode(Isolate* isolate,
630
                                      const char* buf,
631
                                      size_t buflen,
632
                                      enum encoding encoding,
633
                                      Local<Value>* error) {
634
920377
  CHECK_BUFLEN_IN_RANGE(buflen);
635
636

920377
  if (!buflen && encoding != BUFFER) {
637
171
    return String::Empty(isolate);
638
  }
639
640
  MaybeLocal<String> val;
641
642


920206
  switch (encoding) {
643
3266
    case BUFFER:
644
      {
645
3266
        auto maybe_buf = Buffer::Copy(isolate, buf, buflen);
646
        Local<v8::Object> buf;
647
3266
        if (!maybe_buf.ToLocal(&buf)) {
648
          *error = node::ERR_MEMORY_ALLOCATION_FAILED(isolate);
649
        }
650
3266
        return buf;
651
      }
652
653
3960
    case ASCII:
654
3960
      if (contains_non_ascii(buf, buflen)) {
655
695
        char* out = node::UncheckedMalloc(buflen);
656
695
        if (out == nullptr) {
657
          *error = node::ERR_MEMORY_ALLOCATION_FAILED(isolate);
658
          return MaybeLocal<Value>();
659
        }
660
695
        force_ascii(buf, out, buflen);
661
695
        return ExternOneByteString::New(isolate, out, buflen, error);
662
      } else {
663
3265
        return ExternOneByteString::NewFromCopy(isolate, buf, buflen, error);
664
      }
665
666
892490
    case UTF8:
667
      {
668
        val = String::NewFromUtf8(isolate,
669
                                  buf,
670
                                  v8::NewStringType::kNormal,
671
892490
                                  buflen);
672
        Local<String> str;
673
892490
        if (!val.ToLocal(&str)) {
674
2
          *error = node::ERR_STRING_TOO_LONG(isolate);
675
        }
676
892490
        return str;
677
      }
678
679
1690
    case LATIN1:
680
1690
      return ExternOneByteString::NewFromCopy(isolate, buf, buflen, error);
681
682
2023
    case BASE64: {
683
2023
      size_t dlen = base64_encoded_size(buflen);
684
2023
      char* dst = node::UncheckedMalloc(dlen);
685
2023
      if (dst == nullptr) {
686
        *error = node::ERR_MEMORY_ALLOCATION_FAILED(isolate);
687
        return MaybeLocal<Value>();
688
      }
689
690
2023
      size_t written = base64_encode(buf, buflen, dst, dlen);
691
2023
      CHECK_EQ(written, dlen);
692
693
2023
      return ExternOneByteString::New(isolate, dst, dlen, error);
694
    }
695
696
3987
    case BASE64URL: {
697
3987
      size_t dlen = base64_encoded_size(buflen, Base64Mode::URL);
698
3987
      char* dst = node::UncheckedMalloc(dlen);
699
3987
      if (dst == nullptr) {
700
        *error = node::ERR_MEMORY_ALLOCATION_FAILED(isolate);
701
        return MaybeLocal<Value>();
702
      }
703
704
3987
      size_t written = base64_encode(buf, buflen, dst, dlen, Base64Mode::URL);
705
3987
      CHECK_EQ(written, dlen);
706
707
3987
      return ExternOneByteString::New(isolate, dst, dlen, error);
708
    }
709
710
7567
    case HEX: {
711
7567
      size_t dlen = buflen * 2;
712
7567
      char* dst = node::UncheckedMalloc(dlen);
713
7567
      if (dst == nullptr) {
714
        *error = node::ERR_MEMORY_ALLOCATION_FAILED(isolate);
715
        return MaybeLocal<Value>();
716
      }
717
7567
      size_t written = hex_encode(buf, buflen, dst, dlen);
718
7567
      CHECK_EQ(written, dlen);
719
720
7567
      return ExternOneByteString::New(isolate, dst, dlen, error);
721
    }
722
723
5223
    case UCS2: {
724
5223
      if (IsBigEndian()) {
725
        uint16_t* dst = node::UncheckedMalloc<uint16_t>(buflen / 2);
726
        if (dst == nullptr) {
727
          *error = node::ERR_MEMORY_ALLOCATION_FAILED(isolate);
728
          return MaybeLocal<Value>();
729
        }
730
        for (size_t i = 0, k = 0; k < buflen / 2; i += 2, k += 1) {
731
          // The input is in *little endian*, because that's what Node.js
732
          // expects, so the high byte comes after the low byte.
733
          const uint8_t hi = static_cast<uint8_t>(buf[i + 1]);
734
          const uint8_t lo = static_cast<uint8_t>(buf[i + 0]);
735
          dst[k] = static_cast<uint16_t>(hi) << 8 | lo;
736
        }
737
        return ExternTwoByteString::New(isolate, dst, buflen / 2, error);
738
      }
739
5223
      if (reinterpret_cast<uintptr_t>(buf) % 2 != 0) {
740
        // Unaligned data still means we can't directly pass it to V8.
741
214
        char* dst = node::UncheckedMalloc(buflen);
742
214
        if (dst == nullptr) {
743
          *error = node::ERR_MEMORY_ALLOCATION_FAILED(isolate);
744
          return MaybeLocal<Value>();
745
        }
746
214
        memcpy(dst, buf, buflen);
747
        return ExternTwoByteString::New(
748
214
            isolate, reinterpret_cast<uint16_t*>(dst), buflen / 2, error);
749
      }
750
      return ExternTwoByteString::NewFromCopy(
751
5009
          isolate, reinterpret_cast<const uint16_t*>(buf), buflen / 2, error);
752
    }
753
754
    default:
755
      CHECK(0 && "unknown encoding");
756
      break;
757
  }
758
759
  UNREACHABLE();
760
}
761
762
763
MaybeLocal<Value> StringBytes::Encode(Isolate* isolate,
764
                                      const uint16_t* buf,
765
                                      size_t buflen,
766
                                      Local<Value>* error) {
767
  CHECK_BUFLEN_IN_RANGE(buflen);
768
769
  // Node's "ucs2" encoding expects LE character data inside a
770
  // Buffer, so we need to reorder on BE platforms.  See
771
  // https://nodejs.org/api/buffer.html regarding Node's "ucs2"
772
  // encoding specification
773
  if (IsBigEndian()) {
774
    uint16_t* dst = node::UncheckedMalloc<uint16_t>(buflen);
775
    if (dst == nullptr) {
776
      *error = node::ERR_MEMORY_ALLOCATION_FAILED(isolate);
777
      return MaybeLocal<Value>();
778
    }
779
    size_t nbytes = buflen * sizeof(uint16_t);
780
    memcpy(dst, buf, nbytes);
781
    SwapBytes16(reinterpret_cast<char*>(dst), nbytes);
782
    return ExternTwoByteString::New(isolate, dst, buflen, error);
783
  } else {
784
    return ExternTwoByteString::NewFromCopy(isolate, buf, buflen, error);
785
  }
786
}
787
788
768257
MaybeLocal<Value> StringBytes::Encode(Isolate* isolate,
789
                                      const char* buf,
790
                                      enum encoding encoding,
791
                                      Local<Value>* error) {
792
768257
  const size_t len = strlen(buf);
793
768257
  return Encode(isolate, buf, len, encoding, error);
794
}
795
796
}  // namespace node