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29#ifndef GOOGLEURL_SRC_URL_CANON_H__
30#define GOOGLEURL_SRC_URL_CANON_H__
31
32#include <memory.h>
33#include <stdlib.h>
34
35#include "base/string16.h"
36#include "googleurl/src/url_common.h"
37#include "googleurl/src/url_parse.h"
38
39namespace url_canon {
40
41// Canonicalizer output -------------------------------------------------------
42
43// Base class for the canonicalizer output, this maintains a buffer and
44// supports simple resizing and append operations on it.
45//
46// It is VERY IMPORTANT that no virtual function calls be made on the common
47// code path. We only have two virtual function calls, the destructor and a
48// resize function that is called when the existing buffer is not big enough.
49// The derived class is then in charge of setting up our buffer which we will
50// manage.
51template<typename T>
52class CanonOutputT {
53 public:
54  CanonOutputT() : buffer_(NULL), buffer_len_(0), cur_len_(0) {
55  }
56  virtual ~CanonOutputT() {
57  }
58
59  // Implemented to resize the buffer. This function should update the buffer
60  // pointer to point to the new buffer, and any old data up to |cur_len_| in
61  // the buffer must be copied over.
62  //
63  // The new size |sz| must be larger than buffer_len_.
64  virtual void Resize(int sz) = 0;
65
66  // Accessor for returning a character at a given position. The input offset
67  // must be in the valid range.
68  inline char at(int offset) const {
69    return buffer_[offset];
70  }
71
72  // Sets the character at the given position. The given position MUST be less
73  // than the length().
74  inline void set(int offset, int ch) {
75    buffer_[offset] = ch;
76  }
77
78  // Returns the number of characters currently in the buffer.
79  inline int length() const {
80    return cur_len_;
81  }
82
83  // Returns the current capacity of the buffer. The length() is the number of
84  // characters that have been declared to be written, but the capacity() is
85  // the number that can be written without reallocation. If the caller must
86  // write many characters at once, it can make sure there is enough capacity,
87  // write the data, then use set_size() to declare the new length().
88  int capacity() const {
89    return buffer_len_;
90  }
91
92  // Called by the user of this class to get the output. The output will NOT
93  // be NULL-terminated. Call length() to get the
94  // length.
95  const T* data() const {
96    return buffer_;
97  }
98  T* data() {
99    return buffer_;
100  }
101
102  // Shortens the URL to the new length. Used for "backing up" when processing
103  // relative paths. This can also be used if an external function writes a lot
104  // of data to the buffer (when using the "Raw" version below) beyond the end,
105  // to declare the new length.
106  //
107  // This MUST NOT be used to expand the size of the buffer beyond capacity().
108  void set_length(int new_len) {
109    cur_len_ = new_len;
110  }
111
112  // This is the most performance critical function, since it is called for
113  // every character.
114  void push_back(T ch) {
115    // In VC2005, putting this common case first speeds up execution
116    // dramatically because this branch is predicted as taken.
117    if (cur_len_ < buffer_len_) {
118      buffer_[cur_len_] = ch;
119      cur_len_++;
120      return;
121    }
122
123    // Grow the buffer to hold at least one more item. Hopefully we won't have
124    // to do this very often.
125    if (!Grow(1))
126      return;
127
128    // Actually do the insertion.
129    buffer_[cur_len_] = ch;
130    cur_len_++;
131  }
132
133  // Appends the given string to the output.
134  void Append(const T* str, int str_len) {
135    if (cur_len_ + str_len > buffer_len_) {
136      if (!Grow(cur_len_ + str_len - buffer_len_))
137        return;
138    }
139    for (int i = 0; i < str_len; i++)
140      buffer_[cur_len_ + i] = str[i];
141    cur_len_ += str_len;
142  }
143
144 protected:
145  // Grows the given buffer so that it can fit at least |min_additional|
146  // characters. Returns true if the buffer could be resized, false on OOM.
147  bool Grow(int min_additional) {
148    static const int kMinBufferLen = 16;
149    int new_len = (buffer_len_ == 0) ? kMinBufferLen : buffer_len_;
150    do {
151      if (new_len >= (1 << 30))  // Prevent overflow below.
152        return false;
153      new_len *= 2;
154    } while (new_len < buffer_len_ + min_additional);
155    Resize(new_len);
156    return true;
157  }
158
159  T* buffer_;
160  int buffer_len_;
161
162  // Used characters in the buffer.
163  int cur_len_;
164};
165
166// Simple implementation of the CanonOutput using new[]. This class
167// also supports a static buffer so if it is allocated on the stack, most
168// URLs can be canonicalized with no heap allocations.
169template<typename T, int fixed_capacity = 1024>
170class RawCanonOutputT : public CanonOutputT<T> {
171 public:
172  RawCanonOutputT() : CanonOutputT<T>() {
173    this->buffer_ = fixed_buffer_;
174    this->buffer_len_ = fixed_capacity;
175  }
176  virtual ~RawCanonOutputT() {
177    if (this->buffer_ != fixed_buffer_)
178      delete[] this->buffer_;
179  }
180
181  virtual void Resize(int sz) {
182    T* new_buf = new T[sz];
183    memcpy(new_buf, this->buffer_,
184           sizeof(T) * (this->cur_len_ < sz ? this->cur_len_ : sz));
185    if (this->buffer_ != fixed_buffer_)
186      delete[] this->buffer_;
187    this->buffer_ = new_buf;
188    this->buffer_len_ = sz;
189  }
190
191 protected:
192  T fixed_buffer_[fixed_capacity];
193};
194
195// Normally, all canonicalization output is in narrow characters. We support
196// the templates so it can also be used internally if a wide buffer is
197// required.
198typedef CanonOutputT<char> CanonOutput;
199typedef CanonOutputT<char16> CanonOutputW;
200
201template<int fixed_capacity>
202class RawCanonOutput : public RawCanonOutputT<char, fixed_capacity> {};
203template<int fixed_capacity>
204class RawCanonOutputW : public RawCanonOutputT<char16, fixed_capacity> {};
205
206// Character set converter ----------------------------------------------------
207//
208// Converts query strings into a custom encoding. The embedder can supply an
209// implementation of this class to interface with their own character set
210// conversion libraries.
211//
212// Embedders will want to see the unit test for the ICU version.
213
214class CharsetConverter {
215 public:
216  CharsetConverter() {}
217  virtual ~CharsetConverter() {}
218
219  // Converts the given input string from UTF-16 to whatever output format the
220  // converter supports. This is used only for the query encoding conversion,
221  // which does not fail. Instead, the converter should insert "invalid
222  // character" characters in the output for invalid sequences, and do the
223  // best it can.
224  //
225  // If the input contains a character not representable in the output
226  // character set, the converter should append the HTML entity sequence in
227  // decimal, (such as "&#20320;") with escaping of the ampersand, number
228  // sign, and semicolon (in the previous example it would be
229  // "%26%2320320%3B"). This rule is based on what IE does in this situation.
230  virtual void ConvertFromUTF16(const char16* input,
231                                int input_len,
232                                CanonOutput* output) = 0;
233};
234
235// Whitespace -----------------------------------------------------------------
236
237// Searches for whitespace that should be removed from the middle of URLs, and
238// removes it. Removed whitespace are tabs and newlines, but NOT spaces. Spaces
239// are preserved, which is what most browsers do. A pointer to the output will
240// be returned, and the length of that output will be in |output_len|.
241//
242// This should be called before parsing if whitespace removal is desired (which
243// it normally is when you are canonicalizing).
244//
245// If no whitespace is removed, this function will not use the buffer and will
246// return a pointer to the input, to avoid the extra copy. If modification is
247// required, the given |buffer| will be used and the returned pointer will
248// point to the beginning of the buffer.
249//
250// Therefore, callers should not use the buffer, since it may actuall be empty,
251// use the computed pointer and |*output_len| instead.
252GURL_API const char* RemoveURLWhitespace(const char* input, int input_len,
253                                         CanonOutputT<char>* buffer,
254                                         int* output_len);
255GURL_API const char16* RemoveURLWhitespace(const char16* input, int input_len,
256                                           CanonOutputT<char16>* buffer,
257                                           int* output_len);
258
259// IDN ------------------------------------------------------------------------
260
261// Converts the Unicode input representing a hostname to ASCII using IDN rules.
262// The output must fall in the ASCII range, but will be encoded in UTF-16.
263//
264// On success, the output will be filled with the ASCII host name and it will
265// return true. Unlike most other canonicalization functions, this assumes that
266// the output is empty. The beginning of the host will be at offset 0, and
267// the length of the output will be set to the length of the new host name.
268//
269// On error, returns false. The output in this case is undefined.
270GURL_API bool IDNToASCII(const char16* src, int src_len, CanonOutputW* output);
271
272// Piece-by-piece canonicalizers ----------------------------------------------
273//
274// These individual canonicalizers append the canonicalized versions of the
275// corresponding URL component to the given std::string. The spec and the
276// previously-identified range of that component are the input. The range of
277// the canonicalized component will be written to the output component.
278//
279// These functions all append to the output so they can be chained. Make sure
280// the output is empty when you start.
281//
282// These functions returns boolean values indicating success. On failure, they
283// will attempt to write something reasonable to the output so that, if
284// displayed to the user, they will recognise it as something that's messed up.
285// Nothing more should ever be done with these invalid URLs, however.
286
287// Scheme: Appends the scheme and colon to the URL. The output component will
288// indicate the range of characters up to but not including the colon.
289//
290// Canonical URLs always have a scheme. If the scheme is not present in the
291// input, this will just write the colon to indicate an empty scheme. Does not
292// append slashes which will be needed before any authority components for most
293// URLs.
294//
295// The 8-bit version requires UTF-8 encoding.
296GURL_API bool CanonicalizeScheme(const char* spec,
297                                 const url_parse::Component& scheme,
298                                 CanonOutput* output,
299                                 url_parse::Component* out_scheme);
300GURL_API bool CanonicalizeScheme(const char16* spec,
301                                 const url_parse::Component& scheme,
302                                 CanonOutput* output,
303                                 url_parse::Component* out_scheme);
304
305// User info: username/password. If present, this will add the delimiters so
306// the output will be "<username>:<password>@" or "<username>@". Empty
307// username/password pairs, or empty passwords, will get converted to
308// nonexistant in the canonical version.
309//
310// The components for the username and password refer to ranges in the
311// respective source strings. Usually, these will be the same string, which
312// is legal as long as the two components don't overlap.
313//
314// The 8-bit version requires UTF-8 encoding.
315GURL_API bool CanonicalizeUserInfo(const char* username_source,
316                                   const url_parse::Component& username,
317                                   const char* password_source,
318                                   const url_parse::Component& password,
319                                   CanonOutput* output,
320                                   url_parse::Component* out_username,
321                                   url_parse::Component* out_password);
322GURL_API bool CanonicalizeUserInfo(const char16* username_source,
323                                   const url_parse::Component& username,
324                                   const char16* password_source,
325                                   const url_parse::Component& password,
326                                   CanonOutput* output,
327                                   url_parse::Component* out_username,
328                                   url_parse::Component* out_password);
329
330
331// This structure holds detailed state exported from the IP/Host canonicalizers.
332// Additional fields may be added as callers require them.
333struct CanonHostInfo {
334  CanonHostInfo() : family(NEUTRAL), num_ipv4_components(0), out_host() {}
335
336  // Convenience function to test if family is an IP address.
337  bool IsIPAddress() const { return family == IPV4 || family == IPV6; }
338
339  // This field summarizes how the input was classified by the canonicalizer.
340  enum Family {
341    NEUTRAL,   // - Doesn't resemble an IP address.  As far as the IP
342               //   canonicalizer is concerned, it should be treated as a
343               //   hostname.
344    BROKEN,    // - Almost an IP, but was not canonicalized.  This could be an
345               //   IPv4 address where truncation occurred, or something
346               //   containing the special characters :[] which did not parse
347               //   as an IPv6 address.  Never attempt to connect to this
348               //   address, because it might actually succeed!
349    IPV4,      // - Successfully canonicalized as an IPv4 address.
350    IPV6,      // - Successfully canonicalized as an IPv6 address.
351  };
352  Family family;
353
354  // If |family| is IPV4, then this is the number of nonempty dot-separated
355  // components in the input text, from 1 to 4.  If |family| is not IPV4,
356  // this value is undefined.
357  int num_ipv4_components;
358
359  // Location of host within the canonicalized output.
360  // CanonicalizeIPAddress() only sets this field if |family| is IPV4 or IPV6.
361  // CanonicalizeHostVerbose() always sets it.
362  url_parse::Component out_host;
363};
364
365
366// Host.
367//
368// The 8-bit version requires UTF-8 encoding.  Use this version when you only
369// need to know whether canonicalization succeeded.
370GURL_API bool CanonicalizeHost(const char* spec,
371                               const url_parse::Component& host,
372                               CanonOutput* output,
373                               url_parse::Component* out_host);
374GURL_API bool CanonicalizeHost(const char16* spec,
375                               const url_parse::Component& host,
376                               CanonOutput* output,
377                               url_parse::Component* out_host);
378
379// Extended version of CanonicalizeHost, which returns additional information.
380// Use this when you need to know whether the hostname was an IP address.
381// A successful return is indicated by host_info->family != BROKEN.  See the
382// definition of CanonHostInfo above for details.
383GURL_API void CanonicalizeHostVerbose(const char* spec,
384                                      const url_parse::Component& host,
385                                      CanonOutput* output,
386                                      CanonHostInfo* host_info);
387GURL_API void CanonicalizeHostVerbose(const char16* spec,
388                                      const url_parse::Component& host,
389                                      CanonOutput* output,
390                                      CanonHostInfo* host_info);
391
392
393// IP addresses.
394//
395// Tries to interpret the given host name as an IPv4 or IPv6 address. If it is
396// an IP address, it will canonicalize it as such, appending it to |output|.
397// Additional status information is returned via the |*host_info| parameter.
398// See the definition of CanonHostInfo above for details.
399//
400// This is called AUTOMATICALLY from the host canonicalizer, which ensures that
401// the input is unescaped and name-prepped, etc. It should not normally be
402// necessary or wise to call this directly.
403GURL_API void CanonicalizeIPAddress(const char* spec,
404                                    const url_parse::Component& host,
405                                    CanonOutput* output,
406                                    CanonHostInfo* host_info);
407GURL_API void CanonicalizeIPAddress(const char16* spec,
408                                    const url_parse::Component& host,
409                                    CanonOutput* output,
410                                    CanonHostInfo* host_info);
411
412// Port: this function will add the colon for the port if a port is present.
413// The caller can pass url_parse::PORT_UNSPECIFIED as the
414// default_port_for_scheme argument if there is no default port.
415//
416// The 8-bit version requires UTF-8 encoding.
417GURL_API bool CanonicalizePort(const char* spec,
418                               const url_parse::Component& port,
419                               int default_port_for_scheme,
420                               CanonOutput* output,
421                               url_parse::Component* out_port);
422GURL_API bool CanonicalizePort(const char16* spec,
423                               const url_parse::Component& port,
424                               int default_port_for_scheme,
425                               CanonOutput* output,
426                               url_parse::Component* out_port);
427
428// Returns the default port for the given canonical scheme, or PORT_UNSPECIFIED
429// if the scheme is unknown.
430GURL_API int DefaultPortForScheme(const char* scheme, int scheme_len);
431
432// Path. If the input does not begin in a slash (including if the input is
433// empty), we'll prepend a slash to the path to make it canonical.
434//
435// The 8-bit version assumes UTF-8 encoding, but does not verify the validity
436// of the UTF-8 (i.e., you can have invalid UTF-8 sequences, invalid
437// characters, etc.). Normally, URLs will come in as UTF-16, so this isn't
438// an issue. Somebody giving us an 8-bit path is responsible for generating
439// the path that the server expects (we'll escape high-bit characters), so
440// if something is invalid, it's their problem.
441GURL_API bool CanonicalizePath(const char* spec,
442                               const url_parse::Component& path,
443                               CanonOutput* output,
444                               url_parse::Component* out_path);
445GURL_API bool CanonicalizePath(const char16* spec,
446                               const url_parse::Component& path,
447                               CanonOutput* output,
448                               url_parse::Component* out_path);
449
450// Canonicalizes the input as a file path. This is like CanonicalizePath except
451// that it also handles Windows drive specs. For example, the path can begin
452// with "c|\" and it will get properly canonicalized to "C:/".
453// The string will be appended to |*output| and |*out_path| will be updated.
454//
455// The 8-bit version requires UTF-8 encoding.
456GURL_API bool FileCanonicalizePath(const char* spec,
457                                   const url_parse::Component& path,
458                                   CanonOutput* output,
459                                   url_parse::Component* out_path);
460GURL_API bool FileCanonicalizePath(const char16* spec,
461                                   const url_parse::Component& path,
462                                   CanonOutput* output,
463                                   url_parse::Component* out_path);
464
465// Query: Prepends the ? if needed.
466//
467// The 8-bit version requires the input to be UTF-8 encoding. Incorrectly
468// encoded characters (in UTF-8 or UTF-16) will be replaced with the Unicode
469// "invalid character." This function can not fail, we always just try to do
470// our best for crazy input here since web pages can set it themselves.
471//
472// This will convert the given input into the output encoding that the given
473// character set converter object provides. The converter will only be called
474// if necessary, for ASCII input, no conversions are necessary.
475//
476// The converter can be NULL. In this case, the output encoding will be UTF-8.
477GURL_API void CanonicalizeQuery(const char* spec,
478                                const url_parse::Component& query,
479                                CharsetConverter* converter,
480                                CanonOutput* output,
481                                url_parse::Component* out_query);
482GURL_API void CanonicalizeQuery(const char16* spec,
483                                const url_parse::Component& query,
484                                CharsetConverter* converter,
485                                CanonOutput* output,
486                                url_parse::Component* out_query);
487
488// Ref: Prepends the # if needed. The output will be UTF-8 (this is the only
489// canonicalizer that does not produce ASCII output). The output is
490// guaranteed to be valid UTF-8.
491//
492// This function will not fail. If the input is invalid UTF-8/UTF-16, we'll use
493// the "Unicode replacement character" for the confusing bits and copy the rest.
494GURL_API void CanonicalizeRef(const char* spec,
495                              const url_parse::Component& path,
496                              CanonOutput* output,
497                              url_parse::Component* out_path);
498GURL_API void CanonicalizeRef(const char16* spec,
499                              const url_parse::Component& path,
500                              CanonOutput* output,
501                              url_parse::Component* out_path);
502
503// Full canonicalizer ---------------------------------------------------------
504//
505// These functions replace any string contents, rather than append as above.
506// See the above piece-by-piece functions for information specific to
507// canonicalizing individual components.
508//
509// The output will be ASCII except the reference fragment, which may be UTF-8.
510//
511// The 8-bit versions require UTF-8 encoding.
512
513// Use for standard URLs with authorities and paths.
514GURL_API bool CanonicalizeStandardURL(const char* spec,
515                                      int spec_len,
516                                      const url_parse::Parsed& parsed,
517                                      CharsetConverter* query_converter,
518                                      CanonOutput* output,
519                                      url_parse::Parsed* new_parsed);
520GURL_API bool CanonicalizeStandardURL(const char16* spec,
521                                      int spec_len,
522                                      const url_parse::Parsed& parsed,
523                                      CharsetConverter* query_converter,
524                                      CanonOutput* output,
525                                      url_parse::Parsed* new_parsed);
526
527// Use for file URLs.
528GURL_API bool CanonicalizeFileURL(const char* spec,
529                                  int spec_len,
530                                  const url_parse::Parsed& parsed,
531                                  CharsetConverter* query_converter,
532                                  CanonOutput* output,
533                                  url_parse::Parsed* new_parsed);
534GURL_API bool CanonicalizeFileURL(const char16* spec,
535                                  int spec_len,
536                                  const url_parse::Parsed& parsed,
537                                  CharsetConverter* query_converter,
538                                  CanonOutput* output,
539                                  url_parse::Parsed* new_parsed);
540
541// Use for path URLs such as javascript. This does not modify the path in any
542// way, for example, by escaping it.
543GURL_API bool CanonicalizePathURL(const char* spec,
544                                  int spec_len,
545                                  const url_parse::Parsed& parsed,
546                                  CanonOutput* output,
547                                  url_parse::Parsed* new_parsed);
548GURL_API bool CanonicalizePathURL(const char16* spec,
549                                  int spec_len,
550                                  const url_parse::Parsed& parsed,
551                                  CanonOutput* output,
552                                  url_parse::Parsed* new_parsed);
553
554// Use for mailto URLs. This "canonicalizes" the url into a path and query
555// component. It does not attempt to merge "to" fields. It uses UTF-8 for
556// the query encoding if there is a query. This is because a mailto URL is
557// really intended for an external mail program, and the encoding of a page,
558// etc. which would influence a query encoding normally are irrelevant.
559GURL_API bool CanonicalizeMailtoURL(const char* spec,
560                                    int spec_len,
561                                    const url_parse::Parsed& parsed,
562                                    CanonOutput* output,
563                                    url_parse::Parsed* new_parsed);
564GURL_API bool CanonicalizeMailtoURL(const char16* spec,
565                                    int spec_len,
566                                    const url_parse::Parsed& parsed,
567                                    CanonOutput* output,
568                                    url_parse::Parsed* new_parsed);
569
570// Part replacer --------------------------------------------------------------
571
572// Internal structure used for storing separate strings for each component.
573// The basic canonicalization functions use this structure internally so that
574// component remplacement (different strings for different components) can be
575// treated on the same code path as regular canonicalization (the same string
576// for each component).
577//
578// A url_parse::Parsed structure usually goes along with this. Those
579// components identify offsets within these strings, so that they can all be
580// in the same string, or spread arbitrarily across different ones.
581//
582// This structures does not own any data. It is the caller's responsibility to
583// ensure that the data the pointers point to stays in scope and is not
584// modified.
585template<typename CHAR>
586struct URLComponentSource {
587  // Constructor normally used by callers wishing to replace components. This
588  // will make them all NULL, which is no replacement. The caller would then
589  // override the components they want to replace.
590  URLComponentSource()
591      : scheme(NULL),
592        username(NULL),
593        password(NULL),
594        host(NULL),
595        port(NULL),
596        path(NULL),
597        query(NULL),
598        ref(NULL) {
599  }
600
601  // Constructor normally used internally to initialize all the components to
602  // point to the same spec.
603  explicit URLComponentSource(const CHAR* default_value)
604      : scheme(default_value),
605        username(default_value),
606        password(default_value),
607        host(default_value),
608        port(default_value),
609        path(default_value),
610        query(default_value),
611        ref(default_value) {
612  }
613
614  const CHAR* scheme;
615  const CHAR* username;
616  const CHAR* password;
617  const CHAR* host;
618  const CHAR* port;
619  const CHAR* path;
620  const CHAR* query;
621  const CHAR* ref;
622};
623
624// This structure encapsulates information on modifying a URL. Each component
625// may either be left unchanged, replaced, or deleted.
626//
627// By default, each component is unchanged. For those components that should be
628// modified, call either Set* or Clear* to modify it.
629//
630// The string passed to Set* functions DOES NOT GET COPIED AND MUST BE KEPT
631// IN SCOPE BY THE CALLER for as long as this object exists!
632//
633// Prefer the 8-bit replacement version if possible since it is more efficient.
634template<typename CHAR>
635class Replacements {
636 public:
637  Replacements() {
638  }
639
640  // Scheme
641  void SetScheme(const CHAR* s, const url_parse::Component& comp) {
642    sources_.scheme = s;
643    components_.scheme = comp;
644  }
645  // Note: we don't have a ClearScheme since this doesn't make any sense.
646  bool IsSchemeOverridden() const { return sources_.scheme != NULL; }
647
648  // Username
649  void SetUsername(const CHAR* s, const url_parse::Component& comp) {
650    sources_.username = s;
651    components_.username = comp;
652  }
653  void ClearUsername() {
654    sources_.username = Placeholder();
655    components_.username = url_parse::Component();
656  }
657  bool IsUsernameOverridden() const { return sources_.username != NULL; }
658
659  // Password
660  void SetPassword(const CHAR* s, const url_parse::Component& comp) {
661    sources_.password = s;
662    components_.password = comp;
663  }
664  void ClearPassword() {
665    sources_.password = Placeholder();
666    components_.password = url_parse::Component();
667  }
668  bool IsPasswordOverridden() const { return sources_.password != NULL; }
669
670  // Host
671  void SetHost(const CHAR* s, const url_parse::Component& comp) {
672    sources_.host = s;
673    components_.host = comp;
674  }
675  void ClearHost() {
676    sources_.host = Placeholder();
677    components_.host = url_parse::Component();
678  }
679  bool IsHostOverridden() const { return sources_.host != NULL; }
680
681  // Port
682  void SetPort(const CHAR* s, const url_parse::Component& comp) {
683    sources_.port = s;
684    components_.port = comp;
685  }
686  void ClearPort() {
687    sources_.port = Placeholder();
688    components_.port = url_parse::Component();
689  }
690  bool IsPortOverridden() const { return sources_.port != NULL; }
691
692  // Path
693  void SetPath(const CHAR* s, const url_parse::Component& comp) {
694    sources_.path = s;
695    components_.path = comp;
696  }
697  void ClearPath() {
698    sources_.path = Placeholder();
699    components_.path = url_parse::Component();
700  }
701  bool IsPathOverridden() const { return sources_.path != NULL; }
702
703  // Query
704  void SetQuery(const CHAR* s, const url_parse::Component& comp) {
705    sources_.query = s;
706    components_.query = comp;
707  }
708  void ClearQuery() {
709    sources_.query = Placeholder();
710    components_.query = url_parse::Component();
711  }
712  bool IsQueryOverridden() const { return sources_.query != NULL; }
713
714  // Ref
715  void SetRef(const CHAR* s, const url_parse::Component& comp) {
716    sources_.ref = s;
717    components_.ref = comp;
718  }
719  void ClearRef() {
720    sources_.ref = Placeholder();
721    components_.ref = url_parse::Component();
722  }
723  bool IsRefOverridden() const { return sources_.ref != NULL; }
724
725  // Getters for the itnernal data. See the variables below for how the
726  // information is encoded.
727  const URLComponentSource<CHAR>& sources() const { return sources_; }
728  const url_parse::Parsed& components() const { return components_; }
729
730 private:
731  // Returns a pointer to a static empty string that is used as a placeholder
732  // to indicate a component should be deleted (see below).
733  const CHAR* Placeholder() {
734    static const CHAR empty_string = 0;
735    return &empty_string;
736  }
737
738  // We support three states:
739  //
740  // Action                 | Source                Component
741  // -----------------------+--------------------------------------------------
742  // Don't change component | NULL                  (unused)
743  // Replace component      | (replacement string)  (replacement component)
744  // Delete component       | (non-NULL)            (invalid component: (0,-1))
745  //
746  // We use a pointer to the empty string for the source when the component
747  // should be deleted.
748  URLComponentSource<CHAR> sources_;
749  url_parse::Parsed components_;
750};
751
752// The base must be an 8-bit canonical URL.
753GURL_API bool ReplaceStandardURL(const char* base,
754                                 const url_parse::Parsed& base_parsed,
755                                 const Replacements<char>& replacements,
756                                 CharsetConverter* query_converter,
757                                 CanonOutput* output,
758                                 url_parse::Parsed* new_parsed);
759GURL_API bool ReplaceStandardURL(const char* base,
760                                 const url_parse::Parsed& base_parsed,
761                                 const Replacements<char16>& replacements,
762                                 CharsetConverter* query_converter,
763                                 CanonOutput* output,
764                                 url_parse::Parsed* new_parsed);
765
766// Replacing some parts of a file URL is not permitted. Everything except
767// the host, path, query, and ref will be ignored.
768GURL_API bool ReplaceFileURL(const char* base,
769                             const url_parse::Parsed& base_parsed,
770                             const Replacements<char>& replacements,
771                             CharsetConverter* query_converter,
772                             CanonOutput* output,
773                             url_parse::Parsed* new_parsed);
774GURL_API bool ReplaceFileURL(const char* base,
775                             const url_parse::Parsed& base_parsed,
776                             const Replacements<char16>& replacements,
777                             CharsetConverter* query_converter,
778                             CanonOutput* output,
779                             url_parse::Parsed* new_parsed);
780
781// Path URLs can only have the scheme and path replaced. All other components
782// will be ignored.
783GURL_API bool ReplacePathURL(const char* base,
784                             const url_parse::Parsed& base_parsed,
785                             const Replacements<char>& replacements,
786                             CanonOutput* output,
787                             url_parse::Parsed* new_parsed);
788GURL_API bool ReplacePathURL(const char* base,
789                             const url_parse::Parsed& base_parsed,
790                             const Replacements<char16>& replacements,
791                             CanonOutput* output,
792                             url_parse::Parsed* new_parsed);
793
794// Mailto URLs can only have the scheme, path, and query replaced.
795// All other components will be ignored.
796GURL_API bool ReplaceMailtoURL(const char* base,
797                               const url_parse::Parsed& base_parsed,
798                               const Replacements<char>& replacements,
799                               CanonOutput* output,
800                               url_parse::Parsed* new_parsed);
801GURL_API bool ReplaceMailtoURL(const char* base,
802                               const url_parse::Parsed& base_parsed,
803                               const Replacements<char16>& replacements,
804                               CanonOutput* output,
805                               url_parse::Parsed* new_parsed);
806
807// Relative URL ---------------------------------------------------------------
808
809// Given an input URL or URL fragment |fragment|, determines if it is a
810// relative or absolute URL and places the result into |*is_relative|. If it is
811// relative, the relevant portion of the URL will be placed into
812// |*relative_component| (there may have been trimmed whitespace, for example).
813// This value is passed to ResolveRelativeURL. If the input is not relative,
814// this value is UNDEFINED (it may be changed by the functin).
815//
816// Returns true on success (we successfully determined the URL is relative or
817// not). Failure means that the combination of URLs doesn't make any sense.
818//
819// The base URL should always be canonical, therefore is ASCII.
820GURL_API bool IsRelativeURL(const char* base,
821                            const url_parse::Parsed& base_parsed,
822                            const char* fragment,
823                            int fragment_len,
824                            bool is_base_hierarchical,
825                            bool* is_relative,
826                            url_parse::Component* relative_component);
827GURL_API bool IsRelativeURL(const char* base,
828                            const url_parse::Parsed& base_parsed,
829                            const char16* fragment,
830                            int fragment_len,
831                            bool is_base_hierarchical,
832                            bool* is_relative,
833                            url_parse::Component* relative_component);
834
835// Given a canonical parsed source URL, a URL fragment known to be relative,
836// and the identified relevant portion of the relative URL (computed by
837// IsRelativeURL), this produces a new parsed canonical URL in |output| and
838// |out_parsed|.
839//
840// It also requires a flag indicating whether the base URL is a file: URL
841// which triggers additional logic.
842//
843// The base URL should be canonical and have a host (may be empty for file
844// URLs) and a path. If it doesn't have these, we can't resolve relative
845// URLs off of it and will return the base as the output with an error flag.
846// Becausee it is canonical is should also be ASCII.
847//
848// The query charset converter follows the same rules as CanonicalizeQuery.
849//
850// Returns true on success. On failure, the output will be "something
851// reasonable" that will be consistent and valid, just probably not what
852// was intended by the web page author or caller.
853GURL_API bool ResolveRelativeURL(const char* base_url,
854                                 const url_parse::Parsed& base_parsed,
855                                 bool base_is_file,
856                                 const char* relative_url,
857                                 const url_parse::Component& relative_component,
858                                 CharsetConverter* query_converter,
859                                 CanonOutput* output,
860                                 url_parse::Parsed* out_parsed);
861GURL_API bool ResolveRelativeURL(const char* base_url,
862                                 const url_parse::Parsed& base_parsed,
863                                 bool base_is_file,
864                                 const char16* relative_url,
865                                 const url_parse::Component& relative_component,
866                                 CharsetConverter* query_converter,
867                                 CanonOutput* output,
868                                 url_parse::Parsed* out_parsed);
869
870}  // namespace url_canon
871
872#endif  // GOOGLEURL_SRC_URL_CANON_H__
873