1 /* 2 * libjingle 3 * Copyright 2013, 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 #include "talk/app/webrtc/mediaconstraintsinterface.h" 29 30 #include "talk/base/stringencode.h" 31 32 namespace webrtc { 33 34 const char MediaConstraintsInterface::kValueTrue[] = "true"; 35 const char MediaConstraintsInterface::kValueFalse[] = "false"; 36 37 // Set |value| to the value associated with the first appearance of |key|, or 38 // return false if |key| is not found. 39 bool MediaConstraintsInterface::Constraints::FindFirst( 40 const std::string& key, std::string* value) const { 41 for (Constraints::const_iterator iter = begin(); iter != end(); ++iter) { 42 if (iter->key == key) { 43 *value = iter->value; 44 return true; 45 } 46 } 47 return false; 48 } 49 50 // Find the highest-priority instance of the boolean-valued constraint) named by 51 // |key| and return its value as |value|. |constraints| can be null. 52 // If |mandatory_constraints| is non-null, it is incremented if the key appears 53 // among the mandatory constraints. 54 // Returns true if the key was found and has a valid boolean value. 55 // If the key appears multiple times as an optional constraint, appearances 56 // after the first are ignored. 57 // Note: Because this uses FindFirst, repeated optional constraints whose 58 // first instance has an unrecognized value are not handled precisely in 59 // accordance with the specification. 60 bool FindConstraint(const MediaConstraintsInterface* constraints, 61 const std::string& key, bool* value, 62 size_t* mandatory_constraints) { 63 std::string string_value; 64 if (!constraints) { 65 return false; 66 } 67 if (constraints->GetMandatory().FindFirst(key, &string_value)) { 68 if (mandatory_constraints) 69 ++*mandatory_constraints; 70 return talk_base::FromString(string_value, value); 71 } 72 if (constraints->GetOptional().FindFirst(key, &string_value)) { 73 return talk_base::FromString(string_value, value); 74 } 75 return false; 76 } 77 78 } // namespace webrtc 79