Move googleurl into the Chrome repo.

url/url_canon_query.cc

+// Copyright 2007, Google Inc.
+// All rights reserved.
+//
+// Redistribution and use in source and binary forms, with or without
+// modification, are permitted provided that the following conditions are
+// met:
+//
+//     * Redistributions of source code must retain the above copyright
+// notice, this list of conditions and the following disclaimer.
+//     * Redistributions in binary form must reproduce the above
+// copyright notice, this list of conditions and the following disclaimer
+// in the documentation and/or other materials provided with the
+// distribution.
+//     * Neither the name of Google Inc. nor the names of its
+// contributors may be used to endorse or promote products derived from
+// this software without specific prior written permission.
+//
+// THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+// "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+// LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
+// A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
+// OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
+// SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
+// LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
+// DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
+// THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+// (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
+// OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+
+#include "googleurl/src/url_canon.h"
+#include "googleurl/src/url_canon_internal.h"
+
+// Query canonicalization in IE
+// ----------------------------
+// IE is very permissive for query parameters specified in links on the page
+// (in contrast to links that it constructs itself based on form data). It does
+// not unescape any character. It does not reject any escape sequence (be they
+// invalid like "%2y" or freaky like %00).
+//
+// IE only escapes spaces and nothing else. Embedded NULLs, tabs (0x09),
+// LF (0x0a), and CR (0x0d) are removed (this probably happens at an earlier
+// layer since they are removed from all portions of the URL). All other
+// characters are passed unmodified. Invalid UTF-16 sequences are preserved as
+// well, with each character in the input being converted to UTF-8. It is the
+// server's job to make sense of this invalid query.
+//
+// Invalid multibyte sequences (for example, invalid UTF-8 on a UTF-8 page)
+// are converted to the invalid character and sent as unescaped UTF-8 (0xef,
+// 0xbf, 0xbd). This may not be canonicalization, the parser may generate these
+// strings before the URL handler ever sees them.
+//
+// Our query canonicalization
+// --------------------------
+// We escape all non-ASCII characters and control characters, like Firefox.
+// This is more conformant to the URL spec, and there do not seem to be many
+// problems relating to Firefox's behavior.
+//
+// Like IE, we will never unescape (although the application may want to try
+// unescaping to present the user with a more understandable URL). We will
+// replace all invalid sequences (including invalid UTF-16 sequences, which IE
+// doesn't) with the "invalid character," and we will escape it.
+
+namespace url_canon {
+
+namespace {
+
+// Returns true if the characters starting at |begin| and going until |end|
+// (non-inclusive) are all representable in 7-bits.
+template<typename CHAR, typename UCHAR>
+bool IsAllASCII(const CHAR* spec, const url_parse::Component& query) {
+  int end = query.end();
+  for (int i = query.begin; i < end; i++) {
+    if (static_cast<UCHAR>(spec[i]) >= 0x80)
+      return false;
+  }
+  return true;
+}
+
+// Appends the given string to the output, escaping characters that do not
+// match the given |type| in SharedCharTypes. This version will accept 8 or 16
+// bit characters, but assumes that they have only 7-bit values. It also assumes
+// that all UTF-8 values are correct, so doesn't bother checking
+template<typename CHAR>
+void AppendRaw8BitQueryString(const CHAR* source, int length,
+                              CanonOutput* output) {
+  for (int i = 0; i < length; i++) {
+    if (!IsQueryChar(static_cast<unsigned char>(source[i])))
+      AppendEscapedChar(static_cast<unsigned char>(source[i]), output);
+    else  // Doesn't need escaping.
+      output->push_back(static_cast<char>(source[i]));
+  }
+}
+
+// Runs the converter on the given UTF-8 input. Since the converter expects
+// UTF-16, we have to convert first. The converter must be non-NULL.
+void RunConverter(const char* spec,
+                  const url_parse::Component& query,
+                  CharsetConverter* converter,
+                  CanonOutput* output) {
+  // This function will replace any misencoded values with the invalid
+  // character. This is what we want so we don't have to check for error.
+  RawCanonOutputW<1024> utf16;
+  ConvertUTF8ToUTF16(&spec[query.begin], query.len, &utf16);
+  converter->ConvertFromUTF16(utf16.data(), utf16.length(), output);
+}
+
+// Runs the converter with the given UTF-16 input. We don't have to do
+// anything, but this overriddden function allows us to use the same code
+// for both UTF-8 and UTF-16 input.
+void RunConverter(const char16* spec,
+                  const url_parse::Component& query,
+                  CharsetConverter* converter,
+                  CanonOutput* output) {
+  converter->ConvertFromUTF16(&spec[query.begin], query.len, output);
+}
+
+template<typename CHAR, typename UCHAR>
+void DoConvertToQueryEncoding(const CHAR* spec,
+                              const url_parse::Component& query,
+                              CharsetConverter* converter,
+                              CanonOutput* output) {
+  if (IsAllASCII<CHAR, UCHAR>(spec, query)) {
+    // Easy: the input can just appended with no character set conversions.
+    AppendRaw8BitQueryString(&spec[query.begin], query.len, output);
+
+  } else {
+    // Harder: convert to the proper encoding first.
+    if (converter) {
+      // Run the converter to get an 8-bit string, then append it, escaping
+      // necessary values.
+      RawCanonOutput<1024> eight_bit;
+      RunConverter(spec, query, converter, &eight_bit);
+      AppendRaw8BitQueryString(eight_bit.data(), eight_bit.length(), output);
+
+    } else {
+      // No converter, do our own UTF-8 conversion.
+      AppendStringOfType(&spec[query.begin], query.len, CHAR_QUERY, output);
+    }
+  }
+}
+
+template<typename CHAR, typename UCHAR>
+void DoCanonicalizeQuery(const CHAR* spec,
+                         const url_parse::Component& query,
+                         CharsetConverter* converter,
+                         CanonOutput* output,
+                         url_parse::Component* out_query) {
+  if (query.len < 0) {
+    *out_query = url_parse::Component();
+    return;
+  }
+
+  output->push_back('?');
+  out_query->begin = output->length();
+
+  DoConvertToQueryEncoding<CHAR, UCHAR>(spec, query, converter, output);
+
+  out_query->len = output->length() - out_query->begin;
+}
+
+}  // namespace
+
+void CanonicalizeQuery(const char* spec,
+                       const url_parse::Component& query,
+                       CharsetConverter* converter,
+                       CanonOutput* output,
+                       url_parse::Component* out_query) {
+  DoCanonicalizeQuery<char, unsigned char>(spec, query, converter,
+                                           output, out_query);
+}
+
+void CanonicalizeQuery(const char16* spec,
+                       const url_parse::Component& query,
+                       CharsetConverter* converter,
+                       CanonOutput* output,
+                       url_parse::Component* out_query) {
+  DoCanonicalizeQuery<char16, char16>(spec, query, converter,
+                                      output, out_query);
+}
+
+void ConvertUTF16ToQueryEncoding(const char16* input,
+                                 const url_parse::Component& query,
+                                 CharsetConverter* converter,
+                                 CanonOutput* output) {
+  DoConvertToQueryEncoding<char16, char16>(input, query,
+                                           converter, output);
+}
+
+}  // namespace url_canon