1.erase the last "#EXT-X-ENDLIST" int the total.m3u8 if stream is republished

2.erase the title "no desc" in m3u8 to reduce size because the title is optional

@@ -303,6 +303,7 @@ SrsHlsMuxer::SrsHlsMuxer()
     async = new SrsAsyncCallWorker();
     context = new SrsTsContext();
     save_m3u8_total = false;
+    m3u8_total_endlist_saved = false;
     total_duraion = 0.0;
 }
 
@@ -791,7 +792,7 @@ int SrsHlsMuxer::segment_close(string log_desc)
 				srs_verbose("write m3u8 header success.");
 
 			} else {
-				ret = total_m3u8_writer.open_append(total_m3u8);
+				ret = total_m3u8_writer.open_write(total_m3u8);
 				if (ret != ERROR_SUCCESS) {
 					srs_error(
 							"open total file %s error:%s reap ts segment, sequence_no=%d, uri=%s, duration=%.2f, start=%"PRId64,
@@ -803,7 +804,12 @@ int SrsHlsMuxer::segment_close(string log_desc)
 				}
 			}
 
+			bool erase_last_endlist = false;
+
 			if (currentSeg->is_sequence_header) {
+				if(	m3u8_total_endlist_saved ){
+					erase_last_endlist = true;
+				}
 				// #EXT-X-DISCONTINUITY\n
 				ss << "#EXT-X-DISCONTINUITY" << SRS_CONSTS_LF;
 				srs_verbose("write m3u8 segment discontinuity success.");
@@ -812,7 +818,7 @@ int SrsHlsMuxer::segment_close(string log_desc)
 			// "#EXTINF:4294967295.208,\n"
 			ss.precision(3);
 			ss.setf(std::ios::fixed, std::ios::floatfield);
-			ss << "#EXTINF:" << currentSeg->duration << ", no desc"
+			ss << "#EXTINF:" << currentSeg->duration << ","//", no desc" //the #EXTINF:<duration>,<title>,title is optional,so remove it to save the space
 					<< SRS_CONSTS_LF;
 			srs_verbose("write m3u8 segment info success.");
 
@@ -821,7 +827,16 @@ int SrsHlsMuxer::segment_close(string log_desc)
 			srs_verbose("write m3u8 segment uri success.");
 
 			if(log_desc == "unpublish"){
-            ss << "#EXT-X-ENDLIST" << SRS_CONSTS_LF;
+				ss << "#EXT-X-ENDLIST" << SRS_CONSTS_LF;
+				m3u8_total_endlist_saved = true;
+			}
+
+			if(erase_last_endlist){
+				int64_t cur_pos = total_m3u8_writer.tellg();
+
+				cur_pos -= sizeof("#EXT-X-ENDLIST");// sizeof("#EXT-X-ENDLIST") = strlen("#EXT-X-ENDLIST") + 1 = strlen("#EXT-X-ENDLIST") + strlen("\n")
+
+				total_m3u8_writer.lseek(cur_pos);
 			}
 
 			// write m3u8 to writer.
@@ -1019,7 +1034,7 @@ int SrsHlsMuxer::_refresh_m3u8(string m3u8_file)
         // "#EXTINF:4294967295.208,\n"
         ss.precision(3);
         ss.setf(std::ios::fixed, std::ios::floatfield);
-        ss << "#EXTINF:" << segment->duration << ", no desc" << SRS_CONSTS_LF;
+        ss << "#EXTINF:" << segment->duration << ","/*", no desc"*/ << SRS_CONSTS_LF;//#EXTINF:<duration>,<title>,title is optional,so remove it to save the space
         srs_verbose("write m3u8 segment info success.");
         
         // {file name}\n

@@ -210,6 +210,7 @@ private:
     std::string total;
     std::string total_url;
     bool save_m3u8_total;
+    bool m3u8_total_endlist_saved;
     //total duration for all segments
     double total_duraion;
 private:

@@ -94,6 +94,32 @@ int SrsFileWriter::open_append(string p)
     return ret;
 }
 
+int SrsFileWriter::open_write(string p)
+{
+    int ret = ERROR_SUCCESS;
+
+    if (fd > 0) {
+        ret = ERROR_SYSTEM_FILE_ALREADY_OPENED;
+        srs_error("file %s already opened. ret=%d", path.c_str(), ret);
+        return ret;
+    }
+
+    int flags = O_CREAT|O_WRONLY;
+    mode_t mode = S_IRUSR|S_IWUSR|S_IRGRP|S_IWGRP|S_IROTH;
+
+    if ((fd = ::open(p.c_str(), flags, mode)) < 0) {
+        ret = ERROR_SYSTEM_FILE_OPENE;
+        srs_error("open file %s failed. ret=%d", p.c_str(), ret);
+        return ret;
+    }
+
+    ::lseek(fd, 0l, SEEK_END);
+
+    path = p;
+
+    return ret;
+}
+
 void SrsFileWriter::close()
 {
     int ret = ERROR_SUCCESS;

@@ -59,6 +59,11 @@ public:
      */
     virtual int open_append(std::string p);
     /**
+     * open file writer, seek to file end.
+     * @param p a string indicates the path of file to open.
+     */
+    virtual int open_write(std::string p);
+    /**
      * close current writer.
      * @remark user can reopen again.
      */