mp4录制文件名添加索引号，防止一秒内生成多个同名文件导致覆盖 (#2542)

实测发现 如果在点播推流时 如果切片大小设置比较小 一秒钟可能产生多个mp4切片
以前切片名称粒度最小为一秒 所以会存在文件覆盖问题

src/Record/MP4Recorder.cpp

@@ -41,16 +41,16 @@ MP4Recorder::~MP4Recorder() {
 void MP4Recorder::createFile() {
     closeFile();
     auto date = getTimeStr("%Y-%m-%d");
-    auto time = getTimeStr("%H-%M-%S");
-    auto full_path_tmp = _folder_path + date + "/." + time + ".mp4";
-    auto full_path = _folder_path + date + "/" + time + ".mp4";
+    auto file_name = getTimeStr("%H-%M-%S") + "-" + std::to_string(_file_index++) + ".mp4";
+    auto full_path = _folder_path + date + "/" + file_name;
+    auto full_path_tmp = _folder_path + date + "/." + file_name;
 
     /////record 业务逻辑//////
     _info.start_time = ::time(NULL);
-    _info.file_name = time + ".mp4";
+    _info.file_name = file_name;
     _info.file_path = full_path;
     GET_CONFIG(string, appName, Record::kAppName);
-    _info.url = appName + "/" + _info.app + "/" + _info.stream + "/" + date + "/" + time + ".mp4";
+    _info.url = appName + "/" + _info.app + "/" + _info.stream + "/" + date + "/" + file_name;
 
     try {
         _muxer = std::make_shared<MP4Muxer>();

src/Record/MP4Recorder.h

@@ -57,13 +57,14 @@ private:
 private:
     bool _have_video = false;
     size_t _max_second;
+    uint64_t _last_dts = 0;
+    uint64_t _file_index = 0;
     std::string _folder_path;
     std::string _full_path;
     std::string _full_path_tmp;
     RecordInfo _info;
     MP4Muxer::Ptr _muxer;
     std::list<Track::Ptr> _tracks;
-    uint64_t _last_dts = 0;
 };
 
 #endif ///ENABLE_MP4