SmartPtr: Support load test for source by srs-bench. v6.0.130 (#4097)

1. Add live benchmark support in srs-bench, which only connects and
disconnects without any media transport, to test source creation and
disposal and verify source memory leaks.
2. SmartPtr: Support cleanup of HTTP-FLV stream. Unregister the HTTP-FLV
handler for the pattern and clean up the objects and resources.
3. Support benchmarking RTMP/SRT with srs-bench by integrating the gosrt
and oryx RTMP libraries.
4. Refine SRT and RTC sources by using a timer to clean up the sources,
following the same strategy as the Live source.

---------

Co-authored-by: Haibo Chen <495810242@qq.com>
Co-authored-by: Jacob Su <suzp1984@gmail.com>

trunk/3rdparty/srs-bench/vendor/github.com/haivision/srtgo/pollserver.go

@@ -0,0 +1,109 @@
+package srtgo
+
+/*
+#cgo LDFLAGS: -lsrt
+#include <srt/srt.h>
+*/
+import "C"
+
+import (
+	"sync"
+	"unsafe"
+)
+
+var (
+	phctx *pollServer
+	once  sync.Once
+)
+
+func pollServerCtx() *pollServer {
+	once.Do(pollServerCtxInit)
+	return phctx
+}
+
+func pollServerCtxInit() {
+	eid := C.srt_epoll_create()
+	C.srt_epoll_set(eid, C.SRT_EPOLL_ENABLE_EMPTY)
+	phctx = &pollServer{
+		srtEpollDescr: eid,
+		pollDescs:     make(map[C.SRTSOCKET]*pollDesc),
+	}
+	go phctx.run()
+}
+
+type pollServer struct {
+	srtEpollDescr C.int
+	pollDescLock  sync.Mutex
+	pollDescs     map[C.SRTSOCKET]*pollDesc
+}
+
+func (p *pollServer) pollOpen(pd *pollDesc) {
+	//use uint because otherwise with ET it would overflow :/ (srt should accept an uint instead, or fix it's SRT_EPOLL_ET definition)
+	events := C.uint(C.SRT_EPOLL_IN | C.SRT_EPOLL_OUT | C.SRT_EPOLL_ERR | C.SRT_EPOLL_ET)
+	//via unsafe.Pointer because we cannot cast *C.uint to *C.int directly
+	//block poller
+	p.pollDescLock.Lock()
+	ret := C.srt_epoll_add_usock(p.srtEpollDescr, pd.fd, (*C.int)(unsafe.Pointer(&events)))
+	if ret == -1 {
+		panic("ERROR ADDING FD TO EPOLL")
+	}
+	p.pollDescs[pd.fd] = pd
+	p.pollDescLock.Unlock()
+}
+
+func (p *pollServer) pollClose(pd *pollDesc) {
+	sockstate := C.srt_getsockstate(pd.fd)
+	//Broken/closed sockets get removed internally by SRT lib
+	if sockstate == C.SRTS_BROKEN || sockstate == C.SRTS_CLOSING || sockstate == C.SRTS_CLOSED || sockstate == C.SRTS_NONEXIST {
+		return
+	}
+	ret := C.srt_epoll_remove_usock(p.srtEpollDescr, pd.fd)
+	if ret == -1 {
+		panic("ERROR REMOVING FD FROM EPOLL")
+	}
+	p.pollDescLock.Lock()
+	delete(p.pollDescs, pd.fd)
+	p.pollDescLock.Unlock()
+}
+
+func init() {
+
+}
+
+func (p *pollServer) run() {
+	timeoutMs := C.int64_t(-1)
+	fds := [128]C.SRT_EPOLL_EVENT{}
+	fdlen := C.int(128)
+	for {
+		res := C.srt_epoll_uwait(p.srtEpollDescr, &fds[0], fdlen, timeoutMs)
+		if res == 0 {
+			continue //Shouldn't happen with -1
+		} else if res == -1 {
+			panic("srt_epoll_error")
+		} else if res > 0 {
+			max := int(res)
+			if fdlen < res {
+				max = int(fdlen)
+			}
+			p.pollDescLock.Lock()
+			for i := 0; i < max; i++ {
+				s := fds[i].fd
+				events := fds[i].events
+
+				pd := p.pollDescs[s]
+				if events&C.SRT_EPOLL_ERR != 0 {
+					pd.unblock(ModeRead, true, false)
+					pd.unblock(ModeWrite, true, false)
+					continue
+				}
+				if events&C.SRT_EPOLL_IN != 0 {
+					pd.unblock(ModeRead, false, true)
+				}
+				if events&C.SRT_EPOLL_OUT != 0 {
+					pd.unblock(ModeWrite, false, true)
+				}
+			}
+			p.pollDescLock.Unlock()
+		}
+	}
+}