url/url_parse_file.cc - monet - Git at Google

 // Copyright 2013 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.

 #include "base/logging.h"
 #include "url/url_file.h"
 #include "url/url_parse.h"
 #include "url/url_parse_internal.h"

 // Interesting IE file:isms...
 //
 //  INPUT                      OUTPUT
 //  =========================  ==============================
 //  file:/foo/bar              file:///foo/bar
 //      The result here seems totally invalid!?!? This isn't UNC.
 //
 //  file:/
 //  file:// or any other number of slashes
 //      IE6 doesn't do anything at all if you click on this link. No error:
 //      nothing. IE6's history system seems to always color this link, so I'm
 //      guessing that it maps internally to the empty URL.
 //
 //  C:\                        file:///C:/
 //      When on a file: URL source page, this link will work. When over HTTP,
 //      the file: URL will appear in the status bar but the link will not work
 //      (security restriction for all file URLs).
 //
 //  file:foo/                  file:foo/     (invalid?!?!?)
 //  file:/foo/                 file:///foo/  (invalid?!?!?)
 //  file://foo/                file://foo/   (UNC to server "foo")
 //  file:///foo/               file:///foo/  (invalid, seems to be a file)
 //  file:////foo/              file://foo/   (UNC to server "foo")
 //      Any more than four slashes is also treated as UNC.
 //
 //  file:C:/                   file://C:/
 //  file:/C:/                  file://C:/
 //      The number of slashes after "file:" don't matter if the thing following
 //      it looks like an absolute drive path. Also, slashes and backslashes are
 //      equally valid here.

 namespace url {

 namespace {

 // A subcomponent of DoInitFileURL, the input of this function should be a UNC
 // path name, with the index of the first character after the slashes following
 // the scheme given in |after_slashes|. This will initialize the host, path,
 // query, and ref, and leave the other output components untouched
 // (DoInitFileURL handles these for us).
 template<typename CHAR>
 void DoParseUNC(const CHAR* spec,
                 int after_slashes,
                 int spec_len,
                Parsed* parsed) {
   int next_slash = FindNextSlash(spec, after_slashes, spec_len);
   if (next_slash == spec_len) {
     // No additional slash found, as in "file://foo", treat the text as the
     // host with no path (this will end up being UNC to server "foo").
     int host_len = spec_len - after_slashes;
     if (host_len)
       parsed->host = Component(after_slashes, host_len);
     else
       parsed->host.reset();
     parsed->path.reset();
     return;
   }

 #ifdef WIN32
   // See if we have something that looks like a path following the first
   // component. As in "file://localhost/c:/", we get "c:/" out. We want to
   // treat this as a having no host but the path given. Works on Windows only.
   if (DoesBeginWindowsDriveSpec(spec, next_slash + 1, spec_len)) {
     parsed->host.reset();
     ParsePathInternal(spec, MakeRange(next_slash, spec_len),
                       &parsed->path, &parsed->query, &parsed->ref);
     return;
   }
 #endif

   // Otherwise, everything up until that first slash we found is the host name,
   // which will end up being the UNC host. For example "file://foo/bar.txt"
   // will get a server name of "foo" and a path of "/bar". Later, on Windows,
   // this should be treated as the filename "\\foo\bar.txt" in proper UNC
   // notation.
   int host_len = next_slash - after_slashes;
   if (host_len)
     parsed->host = MakeRange(after_slashes, next_slash);
   else
     parsed->host.reset();
   if (next_slash < spec_len) {
     ParsePathInternal(spec, MakeRange(next_slash, spec_len),
                       &parsed->path, &parsed->query, &parsed->ref);
   } else {
     parsed->path.reset();
   }
 }

 // A subcomponent of DoParseFileURL, the input should be a local file, with the
 // beginning of the path indicated by the index in |path_begin|. This will
 // initialize the host, path, query, and ref, and leave the other output
 // components untouched (DoInitFileURL handles these for us).
 template<typename CHAR>
 void DoParseLocalFile(const CHAR* spec,
                       int path_begin,
                       int spec_len,
                       Parsed* parsed) {
   parsed->host.reset();
   ParsePathInternal(spec, MakeRange(path_begin, spec_len),
                     &parsed->path, &parsed->query, &parsed->ref);
 }

 // Backend for the external functions that operates on either char type.
 // Handles cases where there is a scheme, but also when handed the first
 // character following the "file:" at the beginning of the spec. If so,
 // this is usually a slash, but needn't be; we allow paths like "file:c:\foo".
 template<typename CHAR>
 void DoParseFileURL(const CHAR* spec, int spec_len, Parsed* parsed) {
   DCHECK(spec_len >= 0);

   // Get the parts we never use for file URLs out of the way.
   parsed->username.reset();
   parsed->password.reset();
   parsed->port.reset();

   // Many of the code paths don't set these, so it's convenient to just clear
   // them. We'll write them in those cases we need them.
   parsed->query.reset();
   parsed->ref.reset();

   // Strip leading & trailing spaces and control characters.
   int begin = 0;
   TrimURL(spec, &begin, &spec_len);

   // Find the scheme, if any.
   int num_slashes = CountConsecutiveSlashes(spec, begin, spec_len);
   int after_scheme;
   int after_slashes;
 #ifdef WIN32
   // See how many slashes there are. We want to handle cases like UNC but also
   // "/c:/foo". This is when there is no scheme, so we can allow pages to do
   // links like "c:/foo/bar" or "//foo/bar". This is also called by the
   // relative URL resolver when it determines there is an absolute URL, which
   // may give us input like "/c:/foo".
   after_slashes = begin + num_slashes;
   if (DoesBeginWindowsDriveSpec(spec, after_slashes, spec_len)) {
     // Windows path, don't try to extract the scheme (for example, "c:\foo").
     parsed->scheme.reset();
     after_scheme = after_slashes;
   } else if (DoesBeginUNCPath(spec, begin, spec_len, false)) {
     // Windows UNC path: don't try to extract the scheme, but keep the slashes.
     parsed->scheme.reset();
     after_scheme = begin;
   } else
 #endif
   {
     // ExtractScheme doesn't understand the possibility of filenames with
     // colons in them, in which case it returns the entire spec up to the
     // colon as the scheme. So handle /foo.c:5 as a file but foo.c:5 as
     // the foo.c: scheme.
     if (!num_slashes &&
         ExtractScheme(&spec[begin], spec_len - begin, &parsed->scheme)) {
       // Offset the results since we gave ExtractScheme a substring.
       parsed->scheme.begin += begin;
       after_scheme = parsed->scheme.end() + 1;
     } else {
       // No scheme found, remember that.
       parsed->scheme.reset();
       after_scheme = begin;
     }
   }

   // Handle empty specs ones that contain only whitespace or control chars,
   // or that are just the scheme (for example "file:").
   if (after_scheme == spec_len) {
     parsed->host.reset();
     parsed->path.reset();
     return;
   }

   num_slashes = CountConsecutiveSlashes(spec, after_scheme, spec_len);
   after_slashes = after_scheme + num_slashes;
 #ifdef WIN32
   // Check whether the input is a drive again. We checked above for windows
   // drive specs, but that's only at the very beginning to see if we have a
   // scheme at all. This test will be duplicated in that case, but will
   // additionally handle all cases with a real scheme such as "file:///C:/".
   if (!DoesBeginWindowsDriveSpec(spec, after_slashes, spec_len) &&
       num_slashes != 3) {
     // Anything not beginning with a drive spec ("c:\") on Windows is treated
     // as UNC, with the exception of three slashes which always means a file.
     // Even IE7 treats file:///foo/bar as "/foo/bar", which then fails.
     DoParseUNC(spec, after_slashes, spec_len, parsed);
     return;
   }
 #else
   // file: URL with exactly 2 slashes is considered to have a host component.
   if (num_slashes == 2) {
     DoParseUNC(spec, after_slashes, spec_len, parsed);
     return;
   }
 #endif  // WIN32

   // Easy and common case, the full path immediately follows the scheme
   // (modulo slashes), as in "file://c:/foo". Just treat everything from
   // there to the end as the path. Empty hosts have 0 length instead of -1.
   // We include the last slash as part of the path if there is one.
   DoParseLocalFile(spec,
       num_slashes > 0 ? after_scheme + num_slashes - 1 : after_scheme,
       spec_len, parsed);
 }

 }  // namespace

 void ParseFileURL(const char* url, int url_len, Parsed* parsed) {
   DoParseFileURL(url, url_len, parsed);
 }

 void ParseFileURL(const base::char16* url, int url_len, Parsed* parsed) {
   DoParseFileURL(url, url_len, parsed);
 }

 }  // namespace url
	// Copyright 2013 The Chromium Authors. All rights reserved.
	// Use of this source code is governed by a BSD-style license that can be
	// found in the LICENSE file.

	#include "base/logging.h"
	#include "url/url_file.h"
	#include "url/url_parse.h"
	#include "url/url_parse_internal.h"

	// Interesting IE file:isms...
	//
	// INPUT OUTPUT
	// ========================= ==============================
	// file:/foo/bar file:///foo/bar
	// The result here seems totally invalid!?!? This isn't UNC.
	//
	// file:/
	// file:// or any other number of slashes
	// IE6 doesn't do anything at all if you click on this link. No error:
	// nothing. IE6's history system seems to always color this link, so I'm
	// guessing that it maps internally to the empty URL.
	//
	// C:\ file:///C:/
	// When on a file: URL source page, this link will work. When over HTTP,
	// the file: URL will appear in the status bar but the link will not work
	// (security restriction for all file URLs).
	//
	// file:foo/ file:foo/ (invalid?!?!?)
	// file:/foo/ file:///foo/ (invalid?!?!?)
	// file://foo/ file://foo/ (UNC to server "foo")
	// file:///foo/ file:///foo/ (invalid, seems to be a file)
	// file:////foo/ file://foo/ (UNC to server "foo")
	// Any more than four slashes is also treated as UNC.
	//
	// file:C:/ file://C:/
	// file:/C:/ file://C:/
	// The number of slashes after "file:" don't matter if the thing following
	// it looks like an absolute drive path. Also, slashes and backslashes are
	// equally valid here.

	namespace url {

	namespace {

	// A subcomponent of DoInitFileURL, the input of this function should be a UNC
	// path name, with the index of the first character after the slashes following
	// the scheme given in \|after_slashes\|. This will initialize the host, path,
	// query, and ref, and leave the other output components untouched
	// (DoInitFileURL handles these for us).
	template<typename CHAR>
	void DoParseUNC(const CHAR* spec,
	int after_slashes,
	int spec_len,
	Parsed* parsed) {
	int next_slash = FindNextSlash(spec, after_slashes, spec_len);
	if (next_slash == spec_len) {
	// No additional slash found, as in "file://foo", treat the text as the
	// host with no path (this will end up being UNC to server "foo").
	int host_len = spec_len - after_slashes;
	if (host_len)
	parsed->host = Component(after_slashes, host_len);
	else
	parsed->host.reset();
	parsed->path.reset();
	return;
	}

	#ifdef WIN32
	// See if we have something that looks like a path following the first
	// component. As in "file://localhost/c:/", we get "c:/" out. We want to
	// treat this as a having no host but the path given. Works on Windows only.
	if (DoesBeginWindowsDriveSpec(spec, next_slash + 1, spec_len)) {
	parsed->host.reset();
	ParsePathInternal(spec, MakeRange(next_slash, spec_len),
	&parsed->path, &parsed->query, &parsed->ref);
	return;
	}
	#endif

	// Otherwise, everything up until that first slash we found is the host name,
	// which will end up being the UNC host. For example "file://foo/bar.txt"
	// will get a server name of "foo" and a path of "/bar". Later, on Windows,
	// this should be treated as the filename "\\foo\bar.txt" in proper UNC
	// notation.
	int host_len = next_slash - after_slashes;
	if (host_len)
	parsed->host = MakeRange(after_slashes, next_slash);
	else
	parsed->host.reset();
	if (next_slash < spec_len) {
	ParsePathInternal(spec, MakeRange(next_slash, spec_len),
	&parsed->path, &parsed->query, &parsed->ref);
	} else {
	parsed->path.reset();
	}
	}

	// A subcomponent of DoParseFileURL, the input should be a local file, with the
	// beginning of the path indicated by the index in \|path_begin\|. This will
	// initialize the host, path, query, and ref, and leave the other output
	// components untouched (DoInitFileURL handles these for us).
	template<typename CHAR>
	void DoParseLocalFile(const CHAR* spec,
	int path_begin,
	int spec_len,
	Parsed* parsed) {
	parsed->host.reset();
	ParsePathInternal(spec, MakeRange(path_begin, spec_len),
	&parsed->path, &parsed->query, &parsed->ref);
	}

	// Backend for the external functions that operates on either char type.
	// Handles cases where there is a scheme, but also when handed the first
	// character following the "file:" at the beginning of the spec. If so,
	// this is usually a slash, but needn't be; we allow paths like "file:c:\foo".
	template<typename CHAR>
	void DoParseFileURL(const CHAR* spec, int spec_len, Parsed* parsed) {
	DCHECK(spec_len >= 0);

	// Get the parts we never use for file URLs out of the way.
	parsed->username.reset();
	parsed->password.reset();
	parsed->port.reset();

	// Many of the code paths don't set these, so it's convenient to just clear
	// them. We'll write them in those cases we need them.
	parsed->query.reset();
	parsed->ref.reset();

	// Strip leading & trailing spaces and control characters.
	int begin = 0;
	TrimURL(spec, &begin, &spec_len);

	// Find the scheme, if any.
	int num_slashes = CountConsecutiveSlashes(spec, begin, spec_len);
	int after_scheme;
	int after_slashes;
	#ifdef WIN32
	// See how many slashes there are. We want to handle cases like UNC but also
	// "/c:/foo". This is when there is no scheme, so we can allow pages to do
	// links like "c:/foo/bar" or "//foo/bar". This is also called by the
	// relative URL resolver when it determines there is an absolute URL, which
	// may give us input like "/c:/foo".
	after_slashes = begin + num_slashes;
	if (DoesBeginWindowsDriveSpec(spec, after_slashes, spec_len)) {
	// Windows path, don't try to extract the scheme (for example, "c:\foo").
	parsed->scheme.reset();
	after_scheme = after_slashes;
	} else if (DoesBeginUNCPath(spec, begin, spec_len, false)) {
	// Windows UNC path: don't try to extract the scheme, but keep the slashes.
	parsed->scheme.reset();
	after_scheme = begin;
	} else
	#endif
	{
	// ExtractScheme doesn't understand the possibility of filenames with
	// colons in them, in which case it returns the entire spec up to the
	// colon as the scheme. So handle /foo.c:5 as a file but foo.c:5 as
	// the foo.c: scheme.
	if (!num_slashes &&
	ExtractScheme(&spec[begin], spec_len - begin, &parsed->scheme)) {
	// Offset the results since we gave ExtractScheme a substring.
	parsed->scheme.begin += begin;
	after_scheme = parsed->scheme.end() + 1;
	} else {
	// No scheme found, remember that.
	parsed->scheme.reset();
	after_scheme = begin;
	}
	}

	// Handle empty specs ones that contain only whitespace or control chars,
	// or that are just the scheme (for example "file:").
	if (after_scheme == spec_len) {
	parsed->host.reset();
	parsed->path.reset();
	return;
	}

	num_slashes = CountConsecutiveSlashes(spec, after_scheme, spec_len);
	after_slashes = after_scheme + num_slashes;
	#ifdef WIN32
	// Check whether the input is a drive again. We checked above for windows
	// drive specs, but that's only at the very beginning to see if we have a
	// scheme at all. This test will be duplicated in that case, but will
	// additionally handle all cases with a real scheme such as "file:///C:/".
	if (!DoesBeginWindowsDriveSpec(spec, after_slashes, spec_len) &&
	num_slashes != 3) {
	// Anything not beginning with a drive spec ("c:\") on Windows is treated
	// as UNC, with the exception of three slashes which always means a file.
	// Even IE7 treats file:///foo/bar as "/foo/bar", which then fails.
	DoParseUNC(spec, after_slashes, spec_len, parsed);
	return;
	}
	#else
	// file: URL with exactly 2 slashes is considered to have a host component.
	if (num_slashes == 2) {
	DoParseUNC(spec, after_slashes, spec_len, parsed);
	return;
	}
	#endif // WIN32

	// Easy and common case, the full path immediately follows the scheme
	// (modulo slashes), as in "file://c:/foo". Just treat everything from
	// there to the end as the path. Empty hosts have 0 length instead of -1.
	// We include the last slash as part of the path if there is one.
	DoParseLocalFile(spec,
	num_slashes > 0 ? after_scheme + num_slashes - 1 : after_scheme,
	spec_len, parsed);
	}

	} // namespace

	void ParseFileURL(const char* url, int url_len, Parsed* parsed) {
	DoParseFileURL(url, url_len, parsed);
	}

	void ParseFileURL(const base::char16* url, int url_len, Parsed* parsed) {
	DoParseFileURL(url, url_len, parsed);
	}

	} // namespace url