添加rtcp bye相关代码

src/Rtcp/Rtcp.cpp

@@ -9,6 +9,7 @@
  */
 
 #include <stddef.h>
+#include <assert.h>
 #include "Rtcp.h"
 #include "Util/logger.h"
 
@@ -87,10 +88,20 @@ string RtcpHeader::dumpString() const {
             RtcpPli *rtcp = (RtcpPli *)this;
             return rtcp->dumpString();
         }
+
+        case RtcpType::RTCP_BYE: {
+            RtcpBye *rtcp = (RtcpBye *)this;
+            return rtcp->dumpString();
+        }
+
         default: return StrPrinter << dumpHeader() << hexdump((char *)this + sizeof(*this), length << 2);
     }
 }
 
+size_t RtcpHeader::getSize() const {
+    return (1 + length) << 2;
+}
+
 void RtcpHeader::net2Host(size_t len){
     switch ((RtcpType)pt) {
         case RtcpType::RTCP_SR: {
@@ -116,6 +127,12 @@ void RtcpHeader::net2Host(size_t len){
             pli->net2Host(len);
             break;
         }
+
+        case RtcpType::RTCP_BYE: {
+            RtcpBye *bye = (RtcpBye *)this;
+            bye->net2Host(len);
+            break;
+        }
         default: throw std::runtime_error(StrPrinter << "未处理的rtcp包:" << rtcpTypeToStr((RtcpType) this->pt));
     }
 }
@@ -127,6 +144,10 @@ vector<RtcpHeader *> RtcpHeader::loadFromBytes(char *data, size_t len){
     while (remain > (ssize_t) sizeof(RtcpHeader)) {
         RtcpHeader *rtcp = (RtcpHeader *) ptr;
         auto rtcp_len = (1 + ntohs(rtcp->length)) << 2;
+        if (remain < rtcp_len) {
+            WarnL << "非法的rtcp包,声明的长度超过实际数据长度";
+            break;
+        }
         try {
             rtcp->net2Host(rtcp_len);
             ret.emplace_back(rtcp);
@@ -144,7 +165,7 @@ class BufferRtcp : public Buffer {
 public:
     BufferRtcp(std::shared_ptr<RtcpHeader> rtcp) {
         _rtcp = std::move(rtcp);
-        _size = (htons(_rtcp->length) + 1) << 2;
+        _size = (ntohs(_rtcp->length) + 1) << 2;
     }
 
     ~BufferRtcp() override {}
@@ -440,4 +461,97 @@ void RtcpPli::net2Host(size_t size) {
     ssrc_media = ntohl(ssrc_media);
 }
 
+////////////////////////////////////////////////////////////////////
+
+std::shared_ptr<RtcpBye> RtcpBye::create(const std::initializer_list<uint32_t> &ssrcs, const string &reason) {
+    assert(reason.size() <= 0xFF);
+    auto bytes = alignSize(sizeof(RtcpHeader) + sizeof(uint32_t) * ssrcs.size() + 1 + reason.size());
+    auto ptr = (RtcpBye *) new char[bytes];
+    setupHeader(ptr, RtcpType::RTCP_BYE, ssrcs.size(), bytes);
+
+    auto *ssrc_ptr = &(((RtcpBye *) ptr)->ssrc);
+    for (auto ssrc : ssrcs) {
+        *ssrc_ptr = htonl(ssrc);
+        ++ssrc_ptr;
+    }
+
+    if (!reason.empty()) {
+        uint8_t *reason_len_ptr = (uint8_t *) ptr + sizeof(RtcpHeader) + sizeof(uint32_t) * ssrcs.size();
+        *reason_len_ptr = reason.size() & 0xFF;
+        memcpy(reason_len_ptr + 1, reason.data(), *reason_len_ptr);
+    }
+
+    return std::shared_ptr<RtcpBye>(ptr, [](RtcpBye *ptr) {
+        delete[] (char *) ptr;
+    });
+}
+
+vector<uint32_t *> RtcpBye::getSSRC()  {
+    vector<uint32_t *> ret;
+    uint32_t *ssrc_ptr = &ssrc;
+    for (size_t i = 0; i < report_count; ++i) {
+        ret.emplace_back(ssrc_ptr);
+        ssrc_ptr += 1;
+    }
+    return ret;
+}
+
+string RtcpBye::getReason() const {
+    auto *reason_len_ptr = &reason_len + sizeof(ssrc) * (report_count - 1);
+    if (reason_len_ptr + 1 >= (uint8_t *) this + getSize()) {
+        return "";
+    }
+    return string((char *) reason_len_ptr + 1, *reason_len_ptr);
+}
+
+string RtcpBye::dumpString() const {
+    _StrPrinter printer;
+    printer << RtcpHeader::dumpHeader();
+    for(auto ssrc : ((RtcpBye *)this)->getSSRC()) {
+        printer << "ssrc:" << *ssrc << "\r\n";
+    }
+    printer << "reason:" << getReason();
+    return std::move(printer);
+}
+
+void RtcpBye::net2Host(size_t size) {
+    static const size_t kMinSize = sizeof(RtcpHeader);
+    CHECK_MIN_SIZE(size, kMinSize);
+    RtcpHeader::net2Host();
+
+    uint32_t *ssrc_ptr = &ssrc;
+    size_t offset = kMinSize;
+    size_t i = 0;
+    for (; i < report_count && offset + sizeof(ssrc) <= size; ++i) {
+        *ssrc_ptr = ntohl(*ssrc_ptr);
+        ssrc_ptr += 1;
+        offset += sizeof(ssrc);
+    }
+    //修正ssrc个数
+    CHECK_LENGTH(size, i);
+
+    if (offset < size) {
+        uint8_t *reason_len_ptr = &reason_len + sizeof(ssrc) * (report_count - 1);
+        if (reason_len_ptr + 1 + *reason_len_ptr > (uint8_t *) this + size) {
+            WarnL << "invalid rtcp bye reason length";
+            //修正reason_len长度
+            *reason_len_ptr = ((uint8_t *) this + size - reason_len_ptr - 1) & 0xFF;
+        }
+    }
+}
+
+#if 0
+#include "Util/onceToken.h"
+
+static toolkit::onceToken token([](){
+    auto bye = RtcpBye::create({1,2,3,4,5,6}, "this is a bye reason");
+    auto buffer = RtcpHeader::toBuffer(bye);
+
+    auto rtcps = RtcpHeader::loadFromBytes(buffer->data(), buffer->size());
+    for(auto rtcp : rtcps){
+        std::cout << rtcp->dumpString() << std::endl;
+    }
+});
+#endif
+
 }//namespace mediakit
\ No newline at end of file

src/Rtcp/Rtcp.h

@@ -124,6 +124,12 @@ public:
      */
     string dumpString() const;
 
+    /**
+     * 根据length字段获取rtcp总长度
+     * 使用net2Host转换成主机字节序后才可使用此函数
+     */
+    size_t getSize() const;
+
 protected:
     /**
      * 网络字节序转换为主机字节序
@@ -465,9 +471,7 @@ public:
 
 public:
     /**
-     * 创建SDES包，只赋值了RtcpHeader以及SdesItem对象的length和text部分
-     * @param item_text SdesItem列表，只赋值length和text部分
-     * @return SDES包
+     * 创建pli包
      */
     static std::shared_ptr<RtcpPli> create();
 
@@ -485,6 +489,66 @@ private:
     void net2Host(size_t size);
 } PACKED;
 
+//BYE
+/*
+       0                   1                   2                   3
+       0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1
+      +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
+      |V=2|P|    SC   |   PT=BYE=203  |             length            |
+      +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
+      |                           SSRC/CSRC                           |
+      +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
+      :                              ...                              :
+      +=+=+=+=+=+=+=+=+=+=+=+=+=+=+=+=+=+=+=+=+=+=+=+=+=+=+=+=+=+=+=+=+
+(opt) |     length    |               reason for leaving            ...
+      +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
+*/
+
+class RtcpBye : public RtcpHeader {
+public:
+    friend class RtcpHeader;
+    /* 变长，根据count决定有多少个ssrc */
+    uint32_t ssrc;
+
+    /** 中间可能有若干个 ssrc **/
+
+    /* 可选 */
+    uint8_t reason_len;
+    char reason;
+
+public:
+    /**
+     * 创建bye包
+     * @param ssrc ssrc列表
+     * @param reason 原因
+     * @return rtcp bye包
+     */
+    static std::shared_ptr<RtcpBye> create(const std::initializer_list<uint32_t> &ssrc, const string &reason);
+
+    /**
+     * 获取ssrc列表
+     */
+    vector<uint32_t *> getSSRC();
+
+    /**
+     * 获取原因
+     */
+    string getReason() const;
+
+private:
+    /**
+    * 打印字段详情
+    * 使用net2Host转换成主机字节序后才可使用此函数
+    */
+    string dumpString() const;
+
+    /**
+     * 网络字节序转换为主机字节序
+     * @param size 字节长度，防止内存越界
+     */
+    void net2Host(size_t size);
+} PACKED;
+
 #if defined(_WIN32)
 #pragma pack(pop)
 #endif // defined(_WIN32)