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1 // Copyright 2007, Google Inc.
2 // All rights reserved.
3 //
4 // Redistribution and use in source and binary forms, with or without
5 // modification, are permitted provided that the following conditions are
6 // met:
7 //
8 //     * Redistributions of source code must retain the above copyright
9 // notice, this list of conditions and the following disclaimer.
10 //     * Redistributions in binary form must reproduce the above
11 // copyright notice, this list of conditions and the following disclaimer
12 // in the documentation and/or other materials provided with the
13 // distribution.
14 //     * Neither the name of Google Inc. nor the names of its
15 // contributors may be used to endorse or promote products derived from
16 // this software without specific prior written permission.
17 //
18 // THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
19 // "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
20 // LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
21 // A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
22 // OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
23 // SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
24 // LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
25 // DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
26 // THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
27 // (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
28 // OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
29 
30 #include <cstdio>
31 #include <errno.h>
32 #include <stdlib.h>
33 #include <string>
34 
35 #include "googleurl/src/url_canon_internal.h"
36 
37 namespace url_canon {
38 
39 namespace {
40 
41 template<typename CHAR, typename UCHAR>
DoAppendStringOfType(const CHAR * source,int length,SharedCharTypes type,CanonOutput * output)42 void DoAppendStringOfType(const CHAR* source, int length,
43                           SharedCharTypes type,
44                           CanonOutput* output) {
45   for (int i = 0; i < length; i++) {
46     if (static_cast<UCHAR>(source[i]) >= 0x80) {
47       // ReadChar will fill the code point with kUnicodeReplacementCharacter
48       // when the input is invalid, which is what we want.
49       unsigned code_point;
50       ReadUTFChar(source, &i, length, &code_point);
51       AppendUTF8EscapedValue(code_point, output);
52     } else {
53       // Just append the 7-bit character, possibly escaping it.
54       unsigned char uch = static_cast<unsigned char>(source[i]);
55       if (!IsCharOfType(uch, type))
56         AppendEscapedChar(uch, output);
57       else
58         output->push_back(uch);
59     }
60   }
61 }
62 
63 // This function assumes the input values are all contained in 8-bit,
64 // although it allows any type. Returns true if input is valid, false if not.
65 template<typename CHAR, typename UCHAR>
DoAppendInvalidNarrowString(const CHAR * spec,int begin,int end,CanonOutput * output)66 void DoAppendInvalidNarrowString(const CHAR* spec, int begin, int end,
67                                  CanonOutput* output) {
68   for (int i = begin; i < end; i++) {
69     UCHAR uch = static_cast<UCHAR>(spec[i]);
70     if (uch >= 0x80) {
71       // Handle UTF-8/16 encodings. This call will correctly handle the error
72       // case by appending the invalid character.
73       AppendUTF8EscapedChar(spec, &i, end, output);
74     } else if (uch <= ' ' || uch == 0x7f) {
75       // This function is for error handling, so we escape all control
76       // characters and spaces, but not anything else since we lack
77       // context to do something more specific.
78       AppendEscapedChar(static_cast<unsigned char>(uch), output);
79     } else {
80       output->push_back(static_cast<char>(uch));
81     }
82   }
83 }
84 
85 // Overrides one component, see the url_canon::Replacements structure for
86 // what the various combionations of source pointer and component mean.
DoOverrideComponent(const char * override_source,const url_parse::Component & override_component,const char ** dest,url_parse::Component * dest_component)87 void DoOverrideComponent(const char* override_source,
88                          const url_parse::Component& override_component,
89                          const char** dest,
90                          url_parse::Component* dest_component) {
91   if (override_source) {
92     *dest = override_source;
93     *dest_component = override_component;
94   }
95 }
96 
97 // Similar to DoOverrideComponent except that it takes a UTF-16 input and does
98 // not actually set the output character pointer.
99 //
100 // The input is converted to UTF-8 at the end of the given buffer as a temporary
101 // holding place. The component indentifying the portion of the buffer used in
102 // the |utf8_buffer| will be specified in |*dest_component|.
103 //
104 // This will not actually set any |dest| pointer like DoOverrideComponent
105 // does because all of the pointers will point into the |utf8_buffer|, which
106 // may get resized while we're overriding a subsequent component. Instead, the
107 // caller should use the beginning of the |utf8_buffer| as the string pointer
108 // for all components once all overrides have been prepared.
PrepareUTF16OverrideComponent(const char16 * override_source,const url_parse::Component & override_component,CanonOutput * utf8_buffer,url_parse::Component * dest_component)109 bool PrepareUTF16OverrideComponent(
110     const char16* override_source,
111     const url_parse::Component& override_component,
112     CanonOutput* utf8_buffer,
113     url_parse::Component* dest_component) {
114   bool success = true;
115   if (override_source) {
116     if (!override_component.is_valid()) {
117       // Non-"valid" component (means delete), so we need to preserve that.
118       *dest_component = url_parse::Component();
119     } else {
120       // Convert to UTF-8.
121       dest_component->begin = utf8_buffer->length();
122       success = ConvertUTF16ToUTF8(&override_source[override_component.begin],
123                                    override_component.len, utf8_buffer);
124       dest_component->len = utf8_buffer->length() - dest_component->begin;
125     }
126   }
127   return success;
128 }
129 
130 }  // namespace
131 
132 // See the header file for this array's declaration.
133 const unsigned char kSharedCharTypeTable[0x100] = {
134     0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,  // 0x00 - 0x0f
135     0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,  // 0x10 - 0x1f
136     0,                           // 0x20  ' ' (escape spaces in queries)
137     CHAR_QUERY | CHAR_USERINFO,  // 0x21  !
138     0,                           // 0x22  "
139     0,                           // 0x23  #  (invalid in query since it marks the ref)
140     CHAR_QUERY | CHAR_USERINFO,  // 0x24  $
141     CHAR_QUERY | CHAR_USERINFO,  // 0x25  %
142     CHAR_QUERY | CHAR_USERINFO,  // 0x26  &
143     CHAR_QUERY | CHAR_USERINFO,  // 0x27  '
144     CHAR_QUERY | CHAR_USERINFO,  // 0x28  (
145     CHAR_QUERY | CHAR_USERINFO,  // 0x29  )
146     CHAR_QUERY | CHAR_USERINFO,  // 0x2a  *
147     CHAR_QUERY | CHAR_USERINFO,  // 0x2b  +
148     CHAR_QUERY | CHAR_USERINFO,  // 0x2c  ,
149     CHAR_QUERY | CHAR_USERINFO,  // 0x2d  -
150     CHAR_QUERY | CHAR_USERINFO | CHAR_IPV4,  // 0x2e  .
151     CHAR_QUERY,                              // 0x2f  /
152     CHAR_QUERY | CHAR_USERINFO | CHAR_IPV4 | CHAR_HEX | CHAR_DEC | CHAR_OCT,  // 0x30  0
153     CHAR_QUERY | CHAR_USERINFO | CHAR_IPV4 | CHAR_HEX | CHAR_DEC | CHAR_OCT,  // 0x31  1
154     CHAR_QUERY | CHAR_USERINFO | CHAR_IPV4 | CHAR_HEX | CHAR_DEC | CHAR_OCT,  // 0x32  2
155     CHAR_QUERY | CHAR_USERINFO | CHAR_IPV4 | CHAR_HEX | CHAR_DEC | CHAR_OCT,  // 0x33  3
156     CHAR_QUERY | CHAR_USERINFO | CHAR_IPV4 | CHAR_HEX | CHAR_DEC | CHAR_OCT,  // 0x34  4
157     CHAR_QUERY | CHAR_USERINFO | CHAR_IPV4 | CHAR_HEX | CHAR_DEC | CHAR_OCT,  // 0x35  5
158     CHAR_QUERY | CHAR_USERINFO | CHAR_IPV4 | CHAR_HEX | CHAR_DEC | CHAR_OCT,  // 0x36  6
159     CHAR_QUERY | CHAR_USERINFO | CHAR_IPV4 | CHAR_HEX | CHAR_DEC | CHAR_OCT,  // 0x37  7
160     CHAR_QUERY | CHAR_USERINFO | CHAR_IPV4 | CHAR_HEX | CHAR_DEC,             // 0x38  8
161     CHAR_QUERY | CHAR_USERINFO | CHAR_IPV4 | CHAR_HEX | CHAR_DEC,             // 0x39  9
162     CHAR_QUERY,  // 0x3a  :
163     CHAR_QUERY,  // 0x3b  ;
164     0,           // 0x3c  <  (Try to prevent certain types of XSS.)
165     CHAR_QUERY,  // 0x3d  =
166     0,           // 0x3e  >  (Try to prevent certain types of XSS.)
167     CHAR_QUERY,  // 0x3f  ?
168     CHAR_QUERY,  // 0x40  @
169     CHAR_QUERY | CHAR_USERINFO | CHAR_IPV4 | CHAR_HEX,  // 0x41  A
170     CHAR_QUERY | CHAR_USERINFO | CHAR_IPV4 | CHAR_HEX,  // 0x42  B
171     CHAR_QUERY | CHAR_USERINFO | CHAR_IPV4 | CHAR_HEX,  // 0x43  C
172     CHAR_QUERY | CHAR_USERINFO | CHAR_IPV4 | CHAR_HEX,  // 0x44  D
173     CHAR_QUERY | CHAR_USERINFO | CHAR_IPV4 | CHAR_HEX,  // 0x45  E
174     CHAR_QUERY | CHAR_USERINFO | CHAR_IPV4 | CHAR_HEX,  // 0x46  F
175     CHAR_QUERY | CHAR_USERINFO,  // 0x47  G
176     CHAR_QUERY | CHAR_USERINFO,  // 0x48  H
177     CHAR_QUERY | CHAR_USERINFO,  // 0x49  I
178     CHAR_QUERY | CHAR_USERINFO,  // 0x4a  J
179     CHAR_QUERY | CHAR_USERINFO,  // 0x4b  K
180     CHAR_QUERY | CHAR_USERINFO,  // 0x4c  L
181     CHAR_QUERY | CHAR_USERINFO,  // 0x4d  M
182     CHAR_QUERY | CHAR_USERINFO,  // 0x4e  N
183     CHAR_QUERY | CHAR_USERINFO,  // 0x4f  O
184     CHAR_QUERY | CHAR_USERINFO,  // 0x50  P
185     CHAR_QUERY | CHAR_USERINFO,  // 0x51  Q
186     CHAR_QUERY | CHAR_USERINFO,  // 0x52  R
187     CHAR_QUERY | CHAR_USERINFO,  // 0x53  S
188     CHAR_QUERY | CHAR_USERINFO,  // 0x54  T
189     CHAR_QUERY | CHAR_USERINFO,  // 0x55  U
190     CHAR_QUERY | CHAR_USERINFO,  // 0x56  V
191     CHAR_QUERY | CHAR_USERINFO,  // 0x57  W
192     CHAR_QUERY | CHAR_USERINFO | CHAR_IPV4, // 0x58  X
193     CHAR_QUERY | CHAR_USERINFO,  // 0x59  Y
194     CHAR_QUERY | CHAR_USERINFO,  // 0x5a  Z
195     CHAR_QUERY,  // 0x5b  [
196     CHAR_QUERY,  // 0x5c  '\'
197     CHAR_QUERY,  // 0x5d  ]
198     CHAR_QUERY,  // 0x5e  ^
199     CHAR_QUERY | CHAR_USERINFO,  // 0x5f  _
200     CHAR_QUERY,  // 0x60  `
201     CHAR_QUERY | CHAR_USERINFO | CHAR_IPV4 | CHAR_HEX,  // 0x61  a
202     CHAR_QUERY | CHAR_USERINFO | CHAR_IPV4 | CHAR_HEX,  // 0x62  b
203     CHAR_QUERY | CHAR_USERINFO | CHAR_IPV4 | CHAR_HEX,  // 0x63  c
204     CHAR_QUERY | CHAR_USERINFO | CHAR_IPV4 | CHAR_HEX,  // 0x64  d
205     CHAR_QUERY | CHAR_USERINFO | CHAR_IPV4 | CHAR_HEX,  // 0x65  e
206     CHAR_QUERY | CHAR_USERINFO | CHAR_IPV4 | CHAR_HEX,  // 0x66  f
207     CHAR_QUERY | CHAR_USERINFO,  // 0x67  g
208     CHAR_QUERY | CHAR_USERINFO,  // 0x68  h
209     CHAR_QUERY | CHAR_USERINFO,  // 0x69  i
210     CHAR_QUERY | CHAR_USERINFO,  // 0x6a  j
211     CHAR_QUERY | CHAR_USERINFO,  // 0x6b  k
212     CHAR_QUERY | CHAR_USERINFO,  // 0x6c  l
213     CHAR_QUERY | CHAR_USERINFO,  // 0x6d  m
214     CHAR_QUERY | CHAR_USERINFO,  // 0x6e  n
215     CHAR_QUERY | CHAR_USERINFO,  // 0x6f  o
216     CHAR_QUERY | CHAR_USERINFO,  // 0x70  p
217     CHAR_QUERY | CHAR_USERINFO,  // 0x71  q
218     CHAR_QUERY | CHAR_USERINFO,  // 0x72  r
219     CHAR_QUERY | CHAR_USERINFO,  // 0x73  s
220     CHAR_QUERY | CHAR_USERINFO,  // 0x74  t
221     CHAR_QUERY | CHAR_USERINFO,  // 0x75  u
222     CHAR_QUERY | CHAR_USERINFO,  // 0x76  v
223     CHAR_QUERY | CHAR_USERINFO,  // 0x77  w
224     CHAR_QUERY | CHAR_USERINFO | CHAR_IPV4,  // 0x78  x
225     CHAR_QUERY | CHAR_USERINFO,  // 0x79  y
226     CHAR_QUERY | CHAR_USERINFO,  // 0x7a  z
227     CHAR_QUERY,  // 0x7b  {
228     CHAR_QUERY,  // 0x7c  |
229     CHAR_QUERY,  // 0x7d  }
230     CHAR_QUERY | CHAR_USERINFO,  // 0x7e  ~
231     0,           // 0x7f
232     0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,  // 0x80 - 0x8f
233     0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,  // 0x90 - 0x9f
234     0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,  // 0xa0 - 0xaf
235     0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,  // 0xb0 - 0xbf
236     0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,  // 0xc0 - 0xcf
237     0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,  // 0xd0 - 0xdf
238     0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,  // 0xe0 - 0xef
239     0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,  // 0xf0 - 0xff
240 };
241 
242 const char kHexCharLookup[0x10] = {
243     '0', '1', '2', '3', '4', '5', '6', '7',
244     '8', '9', 'A', 'B', 'C', 'D', 'E', 'F',
245 };
246 
247 const char kCharToHexLookup[8] = {
248     0,         // 0x00 - 0x1f
249     '0',       // 0x20 - 0x3f: digits 0 - 9 are 0x30 - 0x39
250     'A' - 10,  // 0x40 - 0x5f: letters A - F are 0x41 - 0x46
251     'a' - 10,  // 0x60 - 0x7f: letters a - f are 0x61 - 0x66
252     0,         // 0x80 - 0x9F
253     0,         // 0xA0 - 0xBF
254     0,         // 0xC0 - 0xDF
255     0,         // 0xE0 - 0xFF
256 };
257 
258 const char16 kUnicodeReplacementCharacter = 0xfffd;
259 
AppendStringOfType(const char * source,int length,SharedCharTypes type,CanonOutput * output)260 void AppendStringOfType(const char* source, int length,
261                         SharedCharTypes type,
262                         CanonOutput* output) {
263   DoAppendStringOfType<char, unsigned char>(source, length, type, output);
264 }
265 
AppendStringOfType(const char16 * source,int length,SharedCharTypes type,CanonOutput * output)266 void AppendStringOfType(const char16* source, int length,
267                         SharedCharTypes type,
268                         CanonOutput* output) {
269   DoAppendStringOfType<char16, char16>(source, length, type, output);
270 }
271 
AppendInvalidNarrowString(const char * spec,int begin,int end,CanonOutput * output)272 void AppendInvalidNarrowString(const char* spec, int begin, int end,
273                                CanonOutput* output) {
274   DoAppendInvalidNarrowString<char, unsigned char>(spec, begin, end, output);
275 }
276 
AppendInvalidNarrowString(const char16 * spec,int begin,int end,CanonOutput * output)277 void AppendInvalidNarrowString(const char16* spec, int begin, int end,
278                                CanonOutput* output) {
279   DoAppendInvalidNarrowString<char16, char16>(spec, begin, end, output);
280 }
281 
ConvertUTF16ToUTF8(const char16 * input,int input_len,CanonOutput * output)282 bool ConvertUTF16ToUTF8(const char16* input, int input_len,
283                         CanonOutput* output) {
284   bool success = true;
285   for (int i = 0; i < input_len; i++) {
286     unsigned code_point;
287     success &= ReadUTFChar(input, &i, input_len, &code_point);
288     AppendUTF8Value(code_point, output);
289   }
290   return success;
291 }
292 
ConvertUTF8ToUTF16(const char * input,int input_len,CanonOutputT<char16> * output)293 bool ConvertUTF8ToUTF16(const char* input, int input_len,
294                         CanonOutputT<char16>* output) {
295   bool success = true;
296   for (int i = 0; i < input_len; i++) {
297     unsigned code_point;
298     success &= ReadUTFChar(input, &i, input_len, &code_point);
299     AppendUTF16Value(code_point, output);
300   }
301   return success;
302 }
303 
SetupOverrideComponents(const char * base,const Replacements<char> & repl,URLComponentSource<char> * source,url_parse::Parsed * parsed)304 void SetupOverrideComponents(const char* base,
305                              const Replacements<char>& repl,
306                              URLComponentSource<char>* source,
307                              url_parse::Parsed* parsed) {
308   // Get the source and parsed structures of the things we are replacing.
309   const URLComponentSource<char>& repl_source = repl.sources();
310   const url_parse::Parsed& repl_parsed = repl.components();
311 
312   DoOverrideComponent(repl_source.scheme, repl_parsed.scheme,
313                       &source->scheme, &parsed->scheme);
314   DoOverrideComponent(repl_source.username, repl_parsed.username,
315                       &source->username, &parsed->username);
316   DoOverrideComponent(repl_source.password, repl_parsed.password,
317                       &source->password, &parsed->password);
318 
319   // Our host should be empty if not present, so override the default setup.
320   DoOverrideComponent(repl_source.host, repl_parsed.host,
321                       &source->host, &parsed->host);
322   if (parsed->host.len == -1)
323     parsed->host.len = 0;
324 
325   DoOverrideComponent(repl_source.port, repl_parsed.port,
326                       &source->port, &parsed->port);
327   DoOverrideComponent(repl_source.path, repl_parsed.path,
328                       &source->path, &parsed->path);
329   DoOverrideComponent(repl_source.query, repl_parsed.query,
330                       &source->query, &parsed->query);
331   DoOverrideComponent(repl_source.ref, repl_parsed.ref,
332                       &source->ref, &parsed->ref);
333 }
334 
SetupUTF16OverrideComponents(const char * base,const Replacements<char16> & repl,CanonOutput * utf8_buffer,URLComponentSource<char> * source,url_parse::Parsed * parsed)335 bool SetupUTF16OverrideComponents(const char* base,
336                                   const Replacements<char16>& repl,
337                                   CanonOutput* utf8_buffer,
338                                   URLComponentSource<char>* source,
339                                   url_parse::Parsed* parsed) {
340   bool success = true;
341 
342   // Get the source and parsed structures of the things we are replacing.
343   const URLComponentSource<char16>& repl_source = repl.sources();
344   const url_parse::Parsed& repl_parsed = repl.components();
345 
346   success &= PrepareUTF16OverrideComponent(
347       repl_source.scheme, repl_parsed.scheme,
348       utf8_buffer, &parsed->scheme);
349   success &= PrepareUTF16OverrideComponent(
350       repl_source.username, repl_parsed.username,
351       utf8_buffer, &parsed->username);
352   success &= PrepareUTF16OverrideComponent(
353       repl_source.password, repl_parsed.password,
354       utf8_buffer, &parsed->password);
355   success &= PrepareUTF16OverrideComponent(
356       repl_source.host, repl_parsed.host,
357       utf8_buffer, &parsed->host);
358   success &= PrepareUTF16OverrideComponent(
359       repl_source.port, repl_parsed.port,
360       utf8_buffer, &parsed->port);
361   success &= PrepareUTF16OverrideComponent(
362       repl_source.path, repl_parsed.path,
363       utf8_buffer, &parsed->path);
364   success &= PrepareUTF16OverrideComponent(
365       repl_source.query, repl_parsed.query,
366       utf8_buffer, &parsed->query);
367   success &= PrepareUTF16OverrideComponent(
368       repl_source.ref, repl_parsed.ref,
369       utf8_buffer, &parsed->ref);
370 
371   // PrepareUTF16OverrideComponent will not have set the data pointer since the
372   // buffer could be resized, invalidating the pointers. We set the data
373   // pointers for affected components now that the buffer is finalized.
374   if (repl_source.scheme)   source->scheme = utf8_buffer->data();
375   if (repl_source.username) source->username = utf8_buffer->data();
376   if (repl_source.password) source->password = utf8_buffer->data();
377   if (repl_source.host)     source->host = utf8_buffer->data();
378   if (repl_source.port)     source->port = utf8_buffer->data();
379   if (repl_source.path)     source->path = utf8_buffer->data();
380   if (repl_source.query)    source->query = utf8_buffer->data();
381   if (repl_source.ref)      source->ref = utf8_buffer->data();
382 
383   return success;
384 }
385 
386 #ifndef WIN32
387 
_itoa_s(int value,char * buffer,size_t size_in_chars,int radix)388 int _itoa_s(int value, char* buffer, size_t size_in_chars, int radix) {
389   const char* format_str;
390   if (radix == 10)
391     format_str = "%d";
392   else if (radix == 16)
393     format_str = "%x";
394   else
395     return EINVAL;
396 
397   int written = snprintf(buffer, size_in_chars, format_str, value);
398   if (static_cast<size_t>(written) >= size_in_chars) {
399     // Output was truncated, or written was negative.
400     return EINVAL;
401   }
402   return 0;
403 }
404 
_itow_s(int value,char16 * buffer,size_t size_in_chars,int radix)405 int _itow_s(int value, char16* buffer, size_t size_in_chars, int radix) {
406   if (radix != 10)
407     return EINVAL;
408 
409   // No more than 12 characters will be required for a 32-bit integer.
410   // Add an extra byte for the terminating null.
411   char temp[13];
412   int written = snprintf(temp, sizeof(temp), "%d", value);
413   if (static_cast<size_t>(written) >= size_in_chars) {
414     // Output was truncated, or written was negative.
415     return EINVAL;
416   }
417 
418   for (int i = 0; i < written; ++i) {
419     buffer[i] = static_cast<char16>(temp[i]);
420   }
421   buffer[written] = '\0';
422   return 0;
423 }
424 
425 #endif  // !WIN32
426 
427 }  // namespace url_canon
428