1 // Copyright (c) 2011 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.
5 #include "net/base/dns_util.h"
11 // Based on DJB's public domain code.
12 bool DNSDomainFromDot(const base::StringPiece& dotted, std::string* out) {
13 const char* buf = dotted.data();
14 unsigned n = dotted.size();
16 unsigned int labellen = 0; /* <= sizeof label */
18 unsigned int namelen = 0; /* <= sizeof name */
28 if (namelen + labellen + 1 > sizeof name)
30 name[namelen++] = labellen;
31 memcpy(name + namelen, label, labellen);
37 if (labellen >= sizeof label)
39 label[labellen++] = ch;
43 if (namelen + labellen + 1 > sizeof name)
45 name[namelen++] = labellen;
46 memcpy(name + namelen, label, labellen);
51 if (namelen + 1 > sizeof name)
53 if (namelen == 0) // Empty names e.g. "", "." are not valid.
55 name[namelen++] = 0; // This is the root label (of length 0).
57 *out = std::string(name, namelen);
61 std::string DNSDomainToString(const base::StringPiece& domain) {
64 for (unsigned i = 0; i < domain.size() && domain[i]; i += domain[i] + 1) {
75 if (static_cast<unsigned>(domain[i]) + i + 1 > domain.size())
78 domain.substr(i + 1, domain[i]).AppendToString(&ret);
83 std::string TrimEndingDot(const base::StringPiece& host) {
84 base::StringPiece host_trimmed = host;
85 size_t len = host_trimmed.length();
86 if (len > 1 && host_trimmed[len - 1] == '.') {
87 host_trimmed.remove_suffix(1);
89 return host_trimmed.as_string();