1/* 2 * libjingle 3 * Copyright 2010, Google Inc. 4 * 5 * Redistribution and use in source and binary forms, with or without 6 * modification, are permitted provided that the following conditions are met: 7 * 8 * 1. Redistributions of source code must retain the above copyright notice, 9 * this list of conditions and the following disclaimer. 10 * 2. Redistributions in binary form must reproduce the above copyright notice, 11 * this list of conditions and the following disclaimer in the documentation 12 * and/or other materials provided with the distribution. 13 * 3. The name of the author may not be used to endorse or promote products 14 * derived from this software without specific prior written permission. 15 * 16 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR IMPLIED 17 * WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF 18 * MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO 19 * EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, 20 * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, 21 * PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; 22 * OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, 23 * WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR 24 * OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF 25 * ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. 26 */ 27 28#ifndef TALK_P2P_BASE_PARSING_H_ 29#define TALK_P2P_BASE_PARSING_H_ 30 31#include <string> 32#include <vector> 33#include "webrtc/libjingle/xmllite/xmlelement.h" // Needed to delete ParseError.extra. 34#include "webrtc/base/basictypes.h" 35#include "webrtc/base/stringencode.h" 36 37namespace cricket { 38 39typedef std::vector<buzz::XmlElement*> XmlElements; 40 41// We decided "bool Parse(in, out*, error*)" is generally the best 42// parse signature. "out Parse(in)" doesn't allow for errors. 43// "error* Parse(in, out*)" doesn't allow flexible memory management. 44 45// The error type for parsing. 46struct ParseError { 47 public: 48 // explains the error 49 std::string text; 50 // provide details about what wasn't parsable 51 const buzz::XmlElement* extra; 52 53 ParseError() : extra(NULL) {} 54 55 ~ParseError() { 56 delete extra; 57 } 58 59 void SetText(const std::string& text) { 60 this->text = text; 61 } 62}; 63 64// The error type for writing. 65struct WriteError { 66 std::string text; 67 68 void SetText(const std::string& text) { 69 this->text = text; 70 } 71}; 72 73// Convenience method for returning a message when parsing fails. 74bool BadParse(const std::string& text, ParseError* err); 75 76// Convenience method for returning a message when writing fails. 77bool BadWrite(const std::string& text, WriteError* error); 78 79// helper XML functions 80std::string GetXmlAttr(const buzz::XmlElement* elem, 81 const buzz::QName& name, 82 const std::string& def); 83std::string GetXmlAttr(const buzz::XmlElement* elem, 84 const buzz::QName& name, 85 const char* def); 86// Return true if the value is "true" or "1". 87bool GetXmlAttr(const buzz::XmlElement* elem, 88 const buzz::QName& name, bool def); 89int GetXmlAttr(const buzz::XmlElement* elem, 90 const buzz::QName& name, int def); 91 92template <class T> 93bool GetXmlAttr(const buzz::XmlElement* elem, 94 const buzz::QName& name, 95 T* val_out) { 96 if (!elem->HasAttr(name)) { 97 return false; 98 } 99 std::string unparsed = elem->Attr(name); 100 return rtc::FromString(unparsed, val_out); 101} 102 103template <class T> 104bool GetXmlAttr(const buzz::XmlElement* elem, 105 const buzz::QName& name, 106 const T& def, 107 T* val_out) { 108 if (!elem->HasAttr(name)) { 109 *val_out = def; 110 return true; 111 } 112 return GetXmlAttr(elem, name, val_out); 113} 114 115template <class T> 116bool AddXmlAttr(buzz::XmlElement* elem, 117 const buzz::QName& name, const T& val) { 118 std::string buf; 119 if (!rtc::ToString(val, &buf)) { 120 return false; 121 } 122 elem->AddAttr(name, buf); 123 return true; 124} 125 126template <class T> 127bool SetXmlBody(buzz::XmlElement* elem, const T& val) { 128 std::string buf; 129 if (!rtc::ToString(val, &buf)) { 130 return false; 131 } 132 elem->SetBodyText(buf); 133 return true; 134} 135 136const buzz::XmlElement* GetXmlChild(const buzz::XmlElement* parent, 137 const std::string& name); 138 139bool RequireXmlChild(const buzz::XmlElement* parent, 140 const std::string& name, 141 const buzz::XmlElement** child, 142 ParseError* error); 143bool RequireXmlAttr(const buzz::XmlElement* elem, 144 const buzz::QName& name, 145 std::string* value, 146 ParseError* error); 147void AddXmlAttrIfNonEmpty(buzz::XmlElement* elem, 148 const buzz::QName name, 149 const std::string& value); 150void AddXmlChildren(buzz::XmlElement* parent, 151 const std::vector<buzz::XmlElement*>& children); 152void CopyXmlChildren(const buzz::XmlElement* source, buzz::XmlElement* dest); 153std::vector<buzz::XmlElement*> CopyOfXmlChildren(const buzz::XmlElement* elem); 154 155} // namespace cricket 156 157#endif // TALK_P2P_BASE_PARSING_H_ 158