{"id":297497,"date":"2021-01-18T11:26:59","date_gmt":"2021-01-18T03:26:59","guid":{"rendered":"http:\/\/4563.org\/?p=297497"},"modified":"2021-01-18T11:26:59","modified_gmt":"2021-01-18T03:26:59","slug":"golang-%e5%a6%82%e4%bd%95%e8%bf%9c%e7%a8%8b%e8%b0%83%e8%af%95%e4%bb%a3%e7%a0%81%ef%bc%9f","status":"publish","type":"post","link":"http:\/\/4563.org\/?p=297497","title":{"rendered":"golang \u5982\u4f55\u8fdc\u7a0b\u8c03\u8bd5\u4ee3\u7801\uff1f"},"content":{"rendered":"<div>\n<div>\n<div>\n<h1>                  golang \u5982\u4f55\u8fdc\u7a0b\u8c03\u8bd5\u4ee3\u7801\uff1f               <\/h1>\n<p> <\/p>\n<div>\n<div> <span>\u8cc7\u6df1\u5927\u4f6c : douyacun <\/span>  <span><i><\/i> 8<\/span> <\/div>\n<div> <\/div>\n<\/p><\/div>\n<\/p><\/div>\n<\/p><\/div>\n<div isfirst=\"1\"> <\/p>\n<p>\u535a\u5ba2\u5730\u5740\uff1a https:\/\/www.douyacun.com<\/p>\n<p>\u539f\u6587\u94fe\u63a5\uff1a https:\/\/www.douyacun.com\/article\/65021b4fee1f73b55ba77b46bb18b3a7<\/p>\n<p>\u95ee\u9898\uff1a <strong>epoll \u8fd9\u53ea\u80fd\u8fd0\u884c\u5728 linux\uff0c\u6709\u95ee\u9898\u6ca1\u53d1\u8c03\u8bd5\uff0c\u86cb\u75bc\u5417\uff1f<\/strong><\/p>\n<p>\u9996\u5148\u60f3\u5230\u88c5\u4e2a docker\uff0c\u8fd0\u884c\u4e2a centos\uff0c\u7136\u540e\u5bf9\u7740 docker \u53c8\u662f\u4e00\u987f\u64b8\u3002\u8fd8\u662f\u6ca1\u53d1\u8c03\u8bd5\uff0c<\/p>\n<p>gdb \u4e5f\u662f\u53ef\u4ee5\u8c03\u8bd5 go \u7a0b\u5e8f\u7684\uff0c\u95ee\u9898\u662f\uff0c\u8fd9 tm \u4e00\u4e2a\u9879\u76ee\u51e0\u767e\u4e2a\u6587\u4ef6\u90fd\u6709\u4e86\uff0c\u6211 gdb \u600e\u4e48\u65ad\u70b9\u554a\uff0c\u5927\u6982\u7684\u601d\u8def\u5c31\u662f\u4ece\u51fd\u6570\u8c03\u7528\u7684\u5730\u65b9\u5f00\u59cb\u5165\u624b\uff0c\u8fd9\u5565\u65f6\u5019\u662f\u4e2a\u5934\u554a\uff0c\u7b80\u5355\u7684\u8fd8\u884c\uff0c\u679c\u65ad\u653e\u5f03\u4e86<\/p>\n<p>delve dlv \u5176\u5b9e\u5f88\u4e0d\u9519\u7684\uff0c\u4e5f\u80fd\u50cf gdb \u4e00\u6837\u652f\u6301\uff0c\u5bf9 goroutine \u652f\u6301\u4e5f\u5f88\u5b8c\u7f8e\uff0c\u95ee\u9898\u6765\u4e86\uff0cdocker \u8fd0\u884c\u7684 centos\uff0c\u6211\u5c31\u662f\u88c5\u4e2a dlv, <code>go get -u github.com\/go-delve\/delve\/cmd\/dlv<\/code> \u88c5\u4e0d\u52a8\uff0c\u53ea\u80fd\u5fc3\u91cc\u9ed8\u9ed8\u8bc5\u5492\u90a3\u4e2a\u4e0b\u51b3\u5b9a\u5bf9 github \u9650\u901f\u7684\u4eba\u3002google \u6211\u80fd\u7406\u89e3\uff0c\u4f46\u662f github \u8fd9\u4e2a\u771f\u7406\u89e3\u4e0d\u4e86\u3002\u53ea\u80fd\u8d70\u4ee3\u7406\u4e86\u3002\u5173\u4e8e[\u600e\u4e48\u5728 centos \u4e0a\u4f7f\u7528\u4ee3\u7406](\/linux\/centos \u4f7f\u7528 ss \u4ee3\u7406.md)<\/p>\n<p><strong>goland \u914d\u7f6e<\/strong><\/p>\n<p><code>Run\/Edit configurations<\/code> <\/p>\n<p><img decoding=\"async\" loading=\"lazy\" referrerpolicy=\"no-referrer\" rel=\"noreferrer\" src=\"http:\/\/4563.org\/wp-content\/uploads\/2021\/02\/20210202_60197e373e248.png\" alt=\"golang \u5982\u4f55\u8fdc\u7a0b\u8c03\u8bd5\u4ee3\u7801\uff1f\" \/><\/p>\n<p><strong>host \u914d\u7f6e<\/strong><\/p>\n<p>docker \u8fd0\u884c\u7684 centos\uff0c\u521b\u5efa container \u7684\u65f6\u5019\uff0c\u6307\u5b9a <code>-p 2345:2345<\/code> , \u628a\u5bb9\u5668\u7684\u7aef\u53e3\u6620\u5c04\u5230\u5bbf\u4e3b\u673a\u5668\u4e0a\u5c31 ok \u4e86<\/p>\n<p><strong>\u7f16\u8bd1\u8c03\u8bd5<\/strong><\/p>\n<p>goland \u91cc\u9762\u4ecb\u7ecd\u7684\u5f88\u660e\u767d\uff0c\u6709\u4e00\u4e2a\u5751 <code>exec .\/main<\/code>\u7684\u65f6\u5019\u540e\u9762\u600e\u4e48\u4f20\u53c2\u6570\u7ed9\u8c03\u8bd5\u8fdb\u7a0b\uff0c\u6b63\u786e\u7684\u59ff\u52bf: \u540e\u9762\u8ddf <code>--<\/code>\uff0c\u544a\u8bc9 dlv\uff0c\u8fd9\u662f\u7ed9\u8c03\u8bd5\u8fdb\u7a0b\u7528\u7684\u3002<\/p>\n<pre><code>dlv --listen=:9004 --headless=true --api-version=2 --accept-multiclient exec .\/main -- start --env debug <\/code><\/pre>\n<p><strong>dlv listen \u4ee5\u540e\u600e\u4e48\u9000\u51fa\u6765\uff1f<\/strong><\/p>\n<p>\u4e0d\u597d\u610f\u601d\uff0c\u6211\u4e5f\u6ca1\u6709\u627e\u5230\u6b63\u786e\u7684\u59ff\u52bf\uff0c\u4e07\u80fd\u7684\u65b9\u5f0f\uff0c\u65b0\u542f\u52a8\u4e00\u4e2a\u7ec8\u7aef kill \u6389\u4ed6\uff0c\u7136\u540e\u4f1a\u95ee\uff0cdocker \u600e\u4e48 attach \u4ee5\u540e\u8fd8\u662f\u5f53\u524d\u7a97\u53e3\uff0c\u8fd9\u4e2a&#8230;.<\/p>\n<pre><code>docker exec -it centos7 bash <\/code><\/pre>\n<p><strong>\u770b\u4e00\u4e0b\u6211\u8c03\u8bd5\u89e3\u51b3\u7684 bug<\/strong><\/p>\n<pre><code>func start() {  for {   clients, err := hub.Wait()   if err != nil {    logger.Debugf(\"epoll wait %v\", err)    continue   }   for _, client := range clients {       \/\/ \u8fd9\u91cc\u662f 68 \u884c\uff0c\u4e0b\u9762\u8fd9\u4e00\u884c\u4f1a\u62a5 \u7a7a\u6307\u9488 \u7684\u9519\u8bef    bt, opCode, err := wsutil.ReadClientData(client.conn)    if err != nil {     log.Printf(\"read message error: %v\", err)     continue    }    \/\/ \u5904\u7406 ping\/pong\/close    if opCode.IsControl() {     err := wsutil.HandleClientControlMessage(client.conn, wsutil.Message{      OpCode:  opCode,      Payload: bt,     })     if err != nil {      if _, ok := err.(wsutil.ClosedError); ok {       hub.unregister &lt;- *client      }      continue     }     continue    }    cmsg := ClientMessage{}    if err := json.Unmarshal(bt, cmsg); err != nil {     logger.Errorf(\"json unmarshal error: %v\", err)     continue    }    hub.broadcast &lt;- NewDefaultMsg(client, cmsg.Content, cmsg.ChannelId)   }  } } <\/code><\/pre>\n<p>\u62a5\u9519\u4fe1\u606f:<\/p>\n<pre><code>panic: runtime error: invalid memory address or nil pointer dereference [signal SIGSEGV: segmentation violation code=0x1 addr=0x8 pc=0xdf08d4]  goroutine 20 [running]: dyc\/internal\/module\/chat.start()  \/root\/github\/api.douyacun.com\/internal\/module\/chat\/client.go:68 +0x64 created by dyc\/internal\/module\/chat.init.0  \/root\/github\/api.douyacun.com\/internal\/module\/chat\/client.go:26 +0x82 <\/code><\/pre>\n<p>\u53ef\u4ee5\u770b\u51fa\u6765\u662f client \u4e3a nil \u4e86\uff0c\u90a3\u5c31\u51fa\u73b0<code>hub.Wait()<\/code>, \u8c03\u7528 epoll wait \u7684\u65f6\u5019\u8fd4\u56de\u7684 client \u6709 nil\uff0cdebug \u4e00\u4e0b<\/p>\n<p><img decoding=\"async\" loading=\"lazy\" referrerpolicy=\"no-referrer\" rel=\"noreferrer\" src=\"http:\/\/4563.org\/wp-content\/uploads\/2021\/02\/20210202_60197e4885c27.png\" alt=\"golang \u5982\u4f55\u8fdc\u7a0b\u8c03\u8bd5\u4ee3\u7801\uff1f\" \/><\/p>\n<p>wait \u51fd\u6570\u7684\u4ee3\u7801:<\/p>\n<pre><code>func (e *epoll) Wait() ([]*Client, error) {  events := make([]syscall.EpollEvent, 100)  n, err := syscall.EpollWait(e.Fd, events, 100)  if err != nil {   return nil, err  }  connections := make([]*Client, n)  for i := 0; i &lt; n; i++ {   conn := e.connections[int(events[i].Fd)]   connections = append(connections, conn)  }  return connections, nil } <\/code><\/pre>\n<p>next \u4e00\u76f4\u8fd0\u884c\uff0c\u770b\u4e00\u4e0b\u6709\u8fde\u63a5\u8fdb\u6765\u7684\u60c5\u51b5:<\/p>\n<p><img decoding=\"async\" loading=\"lazy\" referrerpolicy=\"no-referrer\" rel=\"noreferrer\" src=\"http:\/\/4563.org\/wp-content\/uploads\/2021\/02\/20210202_60197e4ed2603.png\" alt=\"golang \u5982\u4f55\u8fdc\u7a0b\u8c03\u8bd5\u4ee3\u7801\uff1f\" \/><\/p>\n<p>\u8fd9\u91cc\u5e94\u8be5\u662f\u5bf9<code>syscall.EpollWait<\/code> \u7b2c\u4e8c\u4e2a\u53c2\u6570 events\uff0c \u7b2c\u4e00\u4e2a\u8fd4\u56de\u503c n \u7684\u7406\u89e3\u6709\u95ee\u9898\uff0c\u4f46\u8fd9\u4e0d\u662f\u5173\u952e\uff0c\u5173\u952e\u662f\u8fdc\u7a0b\u8c03\u8bd5\u59ff\u52bf\u6709\u4e86\u3002<\/p>\n<\/p><\/div>\n<div> <b>\u5927\u4f6c\u6709\u8a71\u8aaa<\/b> (<span>2<\/span>)        <\/div>\n<div> <\/div>\n<\/p><\/div>\n<\/p><\/div>\n<ul>\n<li data-pid=\"4997827\" data-uid=\"2\">\n<div>\n<div>\n<div> <span>\u8cc7\u6df1\u5927\u4f6c : yjhatfdu2 <\/span>  <\/div>\n<div> <i title=\"\u5f15\u7528\"><\/i>  <span>          <\/span> <\/div>\n<\/p><\/div>\n<div>                                                             go get \u7528 GOPROXY \u4e0d\u884c\u561b                                                            <\/div>\n<\/p><\/div>\n<\/li>\n<li data-pid=\"4997828\" data-uid=\"2\">\n<div>\n<div>\n<div> <span>\u4e3b<\/span> <span>\u8cc7\u6df1\u5927\u4f6c : douyacun <\/span>  <\/div>\n<div> <i title=\"\u5f15\u7528\"><\/i>  <span>          <\/span> <\/div>\n<\/p><\/div>\n<div>                                                             @yjhatfdu2 <br \/>go get \u53ef\u4ee5\u7528 GOPROXY<\/p>\n<p>\u4e0d\u8fc7\u8fd9\u662f\u5728\u672c\u5730\u8c03\u8bd5 linux \u4e0a\u7684\u4ee3\u7801\uff0c\u56e0\u4e3a\u7528\u5230\u4e86 epoll\uff0cmac \u4e0a\u65e0\u6cd5\u6267\u884c\u7684                                                            <\/p><\/div>\n<\/p><\/div>\n<\/li>\n<li>\n","protected":false},"excerpt":{"rendered":"<p>golang \u5982\u4f55\u8fdc\u7a0b\u8c03\u8bd5\u4ee3\u7801\uff1f &hellip;<\/p>\n","protected":false},"author":1,"featured_media":0,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":[],"categories":[],"tags":[],"_links":{"self":[{"href":"http:\/\/4563.org\/index.php?rest_route=\/wp\/v2\/posts\/297497"}],"collection":[{"href":"http:\/\/4563.org\/index.php?rest_route=\/wp\/v2\/posts"}],"about":[{"href":"http:\/\/4563.org\/index.php?rest_route=\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"http:\/\/4563.org\/index.php?rest_route=\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"http:\/\/4563.org\/index.php?rest_route=%2Fwp%2Fv2%2Fcomments&post=297497"}],"version-history":[{"count":0,"href":"http:\/\/4563.org\/index.php?rest_route=\/wp\/v2\/posts\/297497\/revisions"}],"wp:attachment":[{"href":"http:\/\/4563.org\/index.php?rest_route=%2Fwp%2Fv2%2Fmedia&parent=297497"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"http:\/\/4563.org\/index.php?rest_route=%2Fwp%2Fv2%2Fcategories&post=297497"},{"taxonomy":"post_tag","embeddable":true,"href":"http:\/\/4563.org\/index.php?rest_route=%2Fwp%2Fv2%2Ftags&post=297497"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}