1 // Copyright 2021 The Chromium Authors. All rights reserved.
2 // Use of this source code is governed by a BSD-style license that can be
3 // found in the LICENSE file.
4
5 #include "quiche_platform_impl/quiche_url_utils_impl.h"
6
7 #include <cstddef>
8 #include <cstdint>
9 #include <limits>
10 #include <string>
11
12 #include "absl/container/flat_hash_map.h"
13 #include "absl/container/flat_hash_set.h"
14 #include "absl/strings/str_cat.h"
15 #include "absl/strings/str_replace.h"
16 #include "absl/strings/string_view.h"
17 #include "absl/types/optional.h"
18 #include "url/url_canon.h"
19 #include "url/url_util.h"
20
21 namespace quiche {
22
ExpandURITemplateImpl(const std::string & uri_template,const absl::flat_hash_map<std::string,std::string> & parameters,std::string * target,absl::flat_hash_set<std::string> * vars_found)23 bool ExpandURITemplateImpl(
24 const std::string& uri_template,
25 const absl::flat_hash_map<std::string, std::string>& parameters,
26 std::string* target, absl::flat_hash_set<std::string>* vars_found) {
27 absl::flat_hash_set<std::string> found;
28 std::string result = uri_template;
29 for (const auto& pair : parameters) {
30 const std::string& name = pair.first;
31 const std::string& value = pair.second;
32 std::string name_input = absl::StrCat("{", name, "}");
33 url::RawCanonOutputT<char> canon_value;
34 url::EncodeURIComponent(value.c_str(), value.length(), &canon_value);
35 std::string encoded_value(canon_value.data(), canon_value.length());
36 int num_replaced =
37 absl::StrReplaceAll({{name_input, encoded_value}}, &result);
38 if (num_replaced > 0) {
39 found.insert(name);
40 }
41 }
42 // Remove any remaining variables that were not present in |parameters|.
43 while (true) {
44 size_t start = result.find('{');
45 if (start == std::string::npos) {
46 break;
47 }
48 size_t end = result.find('}');
49 if (end == std::string::npos || end <= start) {
50 return false;
51 }
52 result.erase(start, (end - start) + 1);
53 }
54 if (vars_found != nullptr) {
55 *vars_found = found;
56 }
57 *target = result;
58 return true;
59 }
60
AsciiUrlDecodeImpl(absl::string_view input)61 absl::optional<std::string> AsciiUrlDecodeImpl(absl::string_view input) {
62 std::string input_encoded = std::string(input);
63 url::RawCanonOutputW<1024> canon_output;
64 url::DecodeURLEscapeSequences(input_encoded.c_str(), input_encoded.length(),
65 url::DecodeURLMode::kUTF8,
66 &canon_output);
67 std::string output;
68 output.reserve(canon_output.length());
69 for (int i = 0; i < canon_output.length(); i++) {
70 const uint16_t c = reinterpret_cast<uint16_t*>(canon_output.data())[i];
71 if (c > std::numeric_limits<signed char>::max()) {
72 return absl::nullopt;
73 }
74 output += static_cast<char>(c);
75 }
76 return output;
77 }
78
79 } // namespace quiche
80