xref: /aosp_15_r20/external/webrtc/api/rtp_packet_infos.h (revision d9f758449e529ab9291ac668be2861e7a55c2422)
1 /*
2  *  Copyright (c) 2019 The WebRTC project authors. All Rights Reserved.
3  *
4  *  Use of this source code is governed by a BSD-style license
5  *  that can be found in the LICENSE file in the root of the source
6  *  tree. An additional intellectual property rights grant can be found
7  *  in the file PATENTS.  All contributing project authors may
8  *  be found in the AUTHORS file in the root of the source tree.
9  */
10 
11 #ifndef API_RTP_PACKET_INFOS_H_
12 #define API_RTP_PACKET_INFOS_H_
13 
14 #include <cstdint>
15 #include <utility>
16 #include <vector>
17 
18 #include "api/make_ref_counted.h"
19 #include "api/ref_counted_base.h"
20 #include "api/rtp_packet_info.h"
21 #include "api/scoped_refptr.h"
22 #include "rtc_base/system/rtc_export.h"
23 
24 namespace webrtc {
25 
26 // Semi-immutable structure to hold information about packets used to assemble
27 // an audio or video frame. Uses internal reference counting to make it very
28 // cheap to copy.
29 //
30 // We should ideally just use `std::vector<RtpPacketInfo>` and have it
31 // `std::move()`-ed as the per-packet information is transferred from one object
32 // to another. But moving the info, instead of copying it, is not easily done
33 // for the current video code.
34 class RTC_EXPORT RtpPacketInfos {
35  public:
36   using vector_type = std::vector<RtpPacketInfo>;
37 
38   using value_type = vector_type::value_type;
39   using size_type = vector_type::size_type;
40   using difference_type = vector_type::difference_type;
41   using const_reference = vector_type::const_reference;
42   using const_pointer = vector_type::const_pointer;
43   using const_iterator = vector_type::const_iterator;
44   using const_reverse_iterator = vector_type::const_reverse_iterator;
45 
46   using reference = const_reference;
47   using pointer = const_pointer;
48   using iterator = const_iterator;
49   using reverse_iterator = const_reverse_iterator;
50 
RtpPacketInfos()51   RtpPacketInfos() {}
RtpPacketInfos(const vector_type & entries)52   explicit RtpPacketInfos(const vector_type& entries)
53       : data_(Data::Create(entries)) {}
54 
RtpPacketInfos(vector_type && entries)55   explicit RtpPacketInfos(vector_type&& entries)
56       : data_(Data::Create(std::move(entries))) {}
57 
58   RtpPacketInfos(const RtpPacketInfos& other) = default;
59   RtpPacketInfos(RtpPacketInfos&& other) = default;
60   RtpPacketInfos& operator=(const RtpPacketInfos& other) = default;
61   RtpPacketInfos& operator=(RtpPacketInfos&& other) = default;
62 
63   const_reference operator[](size_type pos) const { return entries()[pos]; }
64 
at(size_type pos)65   const_reference at(size_type pos) const { return entries().at(pos); }
front()66   const_reference front() const { return entries().front(); }
back()67   const_reference back() const { return entries().back(); }
68 
begin()69   const_iterator begin() const { return entries().begin(); }
end()70   const_iterator end() const { return entries().end(); }
rbegin()71   const_reverse_iterator rbegin() const { return entries().rbegin(); }
rend()72   const_reverse_iterator rend() const { return entries().rend(); }
73 
cbegin()74   const_iterator cbegin() const { return entries().cbegin(); }
cend()75   const_iterator cend() const { return entries().cend(); }
crbegin()76   const_reverse_iterator crbegin() const { return entries().crbegin(); }
crend()77   const_reverse_iterator crend() const { return entries().crend(); }
78 
empty()79   bool empty() const { return entries().empty(); }
size()80   size_type size() const { return entries().size(); }
81 
82  private:
83   class Data final : public rtc::RefCountedNonVirtual<Data> {
84    public:
Create(const vector_type & entries)85     static rtc::scoped_refptr<Data> Create(const vector_type& entries) {
86       // Performance optimization for the empty case.
87       if (entries.empty()) {
88         return nullptr;
89       }
90 
91       return rtc::make_ref_counted<Data>(entries);
92     }
93 
Create(vector_type && entries)94     static rtc::scoped_refptr<Data> Create(vector_type&& entries) {
95       // Performance optimization for the empty case.
96       if (entries.empty()) {
97         return nullptr;
98       }
99 
100       return rtc::make_ref_counted<Data>(std::move(entries));
101     }
102 
entries()103     const vector_type& entries() const { return entries_; }
104 
Data(const vector_type & entries)105     explicit Data(const vector_type& entries) : entries_(entries) {}
Data(vector_type && entries)106     explicit Data(vector_type&& entries) : entries_(std::move(entries)) {}
107     ~Data() = default;
108 
109    private:
110     const vector_type entries_;
111   };
112 
empty_entries()113   static const vector_type& empty_entries() {
114     static const vector_type& value = *new vector_type();
115     return value;
116   }
117 
entries()118   const vector_type& entries() const {
119     if (data_ != nullptr) {
120       return data_->entries();
121     } else {
122       return empty_entries();
123     }
124   }
125 
126   rtc::scoped_refptr<Data> data_;
127 };
128 
129 }  // namespace webrtc
130 
131 #endif  // API_RTP_PACKET_INFOS_H_
132