refine config, add comments.

@@ -1431,91 +1431,113 @@ vector<SrsConfDirective*> SrsConfig::get_vhosts()
     return vhosts;
 }
 
-SrsConfDirective* SrsConfig::get_vhost_on_connect(string vhost)
+bool SrsConfig::get_vhost_enabled(string vhost)
 {
-    SrsConfDirective* conf = get_vhost(vhost);
+    SrsConfDirective* vhost_conf = get_vhost(vhost);
     
-    if (!conf) { 
-        return NULL;
+    return get_vhost_enabled(vhost_conf);
+}
+
+bool SrsConfig::get_vhost_enabled(SrsConfDirective* vhost)
+{
+    if (!vhost) {
+        return false;
     }
     
-    conf = conf->get("http_hooks");
+    SrsConfDirective* conf = vhost->get("enabled");
     if (!conf) {
-        return NULL;
+        return true;
     }
     
-    SrsConfDirective* enabled = conf->get("enabled");
-    if (!enabled || enabled->arg0() != "on") {
-        return NULL;
+    if (conf->arg0() == "off") {
+        return false;
     }
     
-    return conf->get("on_connect");
+    return true;
 }
 
-SrsConfDirective* SrsConfig::get_vhost_on_close(string vhost)
+bool SrsConfig::get_gop_cache(string vhost)
 {
     SrsConfDirective* conf = get_vhost(vhost);
 
     if (!conf) {
-        return NULL;
+        return true;
     }
     
-    conf = conf->get("http_hooks");
+    conf = conf->get("gop_cache");
+    if (conf && conf->arg0() == "off") {
+        return false;
+    }
+    
+    return true;
+}
+
+bool SrsConfig::get_atc(string vhost)
+{
+    SrsConfDirective* conf = get_vhost(vhost);
+
     if (!conf) {
-        return NULL;
+        return false;
     }
     
-    SrsConfDirective* enabled = conf->get("enabled");
-    if (!enabled || enabled->arg0() != "on") {
-        return NULL;
+    conf = conf->get("atc");
+    if (conf && conf->arg0() == "on") {
+        return true;
     }
     
-    return conf->get("on_close");
+    return false;
 }
 
-SrsConfDirective* SrsConfig::get_vhost_on_publish(string vhost)
+bool SrsConfig::get_atc_auto(string vhost)
 {
     SrsConfDirective* conf = get_vhost(vhost);
 
     if (!conf) {
-        return NULL;
+        return true;
     }
     
-    conf = conf->get("http_hooks");
-    if (!conf) {
-        return NULL;
+    conf = conf->get("atc_auto");
+    if (conf && conf->arg0() == "off") {
+        return false;
     }
     
-    SrsConfDirective* enabled = conf->get("enabled");
-    if (!enabled || enabled->arg0() != "on") {
-        return NULL;
+    return true;
+}
+
+int SrsConfig::get_time_jitter(string vhost)
+{
+    SrsConfDirective* dvr = get_vhost(vhost);
+    
+    std::string time_jitter = SRS_CONF_DEFAULT_TIME_JITTER;
+    
+    if (dvr) {
+        SrsConfDirective* conf = dvr->get("time_jitter");
+    
+        if (conf) {
+            time_jitter = conf->arg0();
+        }
     }
     
-    return conf->get("on_publish");
+    return _srs_time_jitter_string2int(time_jitter);
 }
 
-SrsConfDirective* SrsConfig::get_vhost_on_unpublish(string vhost)
+double SrsConfig::get_queue_length(string vhost)
 {
     SrsConfDirective* conf = get_vhost(vhost);
 
     if (!conf) {
-        return NULL;
-    }
-    
-    conf = conf->get("http_hooks");
-    if (!conf) {
-        return NULL;
+        return SRS_CONF_DEFAULT_QUEUE_LENGTH;
     }
     
-    SrsConfDirective* enabled = conf->get("enabled");
-    if (!enabled || enabled->arg0() != "on") {
-        return NULL;
+    conf = conf->get("queue_length");
+    if (!conf || conf->arg0().empty()) {
+        return SRS_CONF_DEFAULT_QUEUE_LENGTH;
     }
     
-    return conf->get("on_unpublish");
+    return ::atoi(conf->arg0().c_str());
 }
 
-SrsConfDirective* SrsConfig::get_vhost_on_play(string vhost)
+SrsConfDirective* SrsConfig::get_refer(string vhost)
 {
     SrsConfDirective* conf = get_vhost(vhost);
 
@@ -1523,41 +1545,66 @@ SrsConfDirective* SrsConfig::get_vhost_on_play(string vhost)
         return NULL;
     }
     
-    conf = conf->get("http_hooks");
+    return conf->get("refer");
+}
+
+SrsConfDirective* SrsConfig::get_refer_play(string vhost)
+{
+    SrsConfDirective* conf = get_vhost(vhost);
+
     if (!conf) {
         return NULL;
     }
     
-    SrsConfDirective* enabled = conf->get("enabled");
-    if (!enabled || enabled->arg0() != "on") {
+    return conf->get("refer_play");
+}
+
+SrsConfDirective* SrsConfig::get_refer_publish(string vhost)
+{
+    SrsConfDirective* conf = get_vhost(vhost);
+
+    if (!conf) {
         return NULL;
     }
     
-    return conf->get("on_play");
+    return conf->get("refer_publish");
 }
 
-SrsConfDirective* SrsConfig::get_vhost_on_stop(string vhost)
+int SrsConfig::get_chunk_size(const string &vhost)
 {
     SrsConfDirective* conf = get_vhost(vhost);
 
     if (!conf) {
-        return NULL;
+        return SRS_CONF_DEFAULT_CHUNK_SIZE;
     }
 
-    conf = conf->get("http_hooks");
+    conf = conf->get("chunk_size");
     if (!conf) {
-        return NULL;
+        // vhost does not specify the chunk size,
+        // use the global instead.
+        conf = root->get("chunk_size");
+        if (!conf) {
+            return SRS_CONF_DEFAULT_CHUNK_SIZE;
         }
         
-    SrsConfDirective* enabled = conf->get("enabled");
-    if (!enabled || enabled->arg0() != "on") {
+        return ::atoi(conf->arg0().c_str());
+    }
+
+    return ::atoi(conf->arg0().c_str());
+}
+
+SrsConfDirective* SrsConfig::get_forward(string vhost)
+{
+    SrsConfDirective* conf = get_vhost(vhost);
+
+    if (!conf) {
         return NULL;
     }
     
-    return conf->get("on_stop");
+    return conf->get("forward");
 }
 
-SrsConfDirective* SrsConfig::get_vhost_on_dvr_hss_reap_flv(string vhost)
+SrsConfDirective* SrsConfig::get_vhost_on_connect(string vhost)
 {
     SrsConfDirective* conf = get_vhost(vhost);
 
@@ -1575,127 +1622,94 @@ SrsConfDirective* SrsConfig::get_vhost_on_dvr_hss_reap_flv(string vhost)
         return NULL;
     }
     
-    return conf->get("on_dvr_hss_reap_flv");
+    return conf->get("on_connect");
 }
 
-bool SrsConfig::get_vhost_enabled(string vhost)
+SrsConfDirective* SrsConfig::get_vhost_on_close(string vhost)
 {
-    SrsConfDirective* vhost_conf = get_vhost(vhost);
-    
-    return get_vhost_enabled(vhost_conf);
-}
+    SrsConfDirective* conf = get_vhost(vhost);
 
-bool SrsConfig::get_vhost_enabled(SrsConfDirective* vhost)
-{
-    if (!vhost) {
-        return false;
+    if (!conf) { 
+        return NULL;
     }
     
-    SrsConfDirective* conf = vhost->get("enabled");
+    conf = conf->get("http_hooks");
     if (!conf) {
-        return true;
+        return NULL;
     }
     
-    if (conf->arg0() == "off") {
-        return false;
+    SrsConfDirective* enabled = conf->get("enabled");
+    if (!enabled || enabled->arg0() != "on") {
+        return NULL;
     }
     
-    return true;
+    return conf->get("on_close");
 }
 
-bool SrsConfig::get_gop_cache(string vhost)
+SrsConfDirective* SrsConfig::get_vhost_on_publish(string vhost)
 {
     SrsConfDirective* conf = get_vhost(vhost);
 
     if (!conf) { 
-        return true;
-    }
-    
-    conf = conf->get("gop_cache");
-    if (conf && conf->arg0() == "off") {
-        return false;
+        return NULL;
     }
     
-    return true;
-}
-
-bool SrsConfig::get_atc(string vhost)
-{
-    SrsConfDirective* conf = get_vhost(vhost);
-
+    conf = conf->get("http_hooks");
     if (!conf) {
-        return false;
+        return NULL;
     }
     
-    conf = conf->get("atc");
-    if (conf && conf->arg0() == "on") {
-        return true;
+    SrsConfDirective* enabled = conf->get("enabled");
+    if (!enabled || enabled->arg0() != "on") {
+        return NULL;
     }
     
-    return false;
+    return conf->get("on_publish");
 }
 
-bool SrsConfig::get_atc_auto(string vhost)
+SrsConfDirective* SrsConfig::get_vhost_on_unpublish(string vhost)
 {
     SrsConfDirective* conf = get_vhost(vhost);
 
     if (!conf) { 
-        return true;
+        return NULL;
     }
     
-    conf = conf->get("atc_auto");
-    if (conf && conf->arg0() == "off") {
-        return false;
+    conf = conf->get("http_hooks");
+    if (!conf) {
+        return NULL;
     }
     
-    return true;
-}
-
-int SrsConfig::get_time_jitter(string vhost)
-{
-    SrsConfDirective* dvr = get_vhost(vhost);
-    
-    std::string time_jitter = SRS_CONF_DEFAULT_TIME_JITTER;
-    
-    if (dvr) {
-        SrsConfDirective* conf = dvr->get("time_jitter");
-    
-        if (conf) {
-            time_jitter = conf->arg0();
-        }
+    SrsConfDirective* enabled = conf->get("enabled");
+    if (!enabled || enabled->arg0() != "on") {
+        return NULL;
     }
     
-    return _srs_time_jitter_string2int(time_jitter);
+    return conf->get("on_unpublish");
 }
 
-double SrsConfig::get_queue_length(string vhost)
+SrsConfDirective* SrsConfig::get_vhost_on_play(string vhost)
 {
     SrsConfDirective* conf = get_vhost(vhost);
 
     if (!conf) { 
-        return SRS_CONF_DEFAULT_QUEUE_LENGTH;
+        return NULL;
     }
     
-    conf = conf->get("queue_length");
-    if (!conf || conf->arg0().empty()) {
-        return SRS_CONF_DEFAULT_QUEUE_LENGTH;
+    conf = conf->get("http_hooks");
+    if (!conf) {
+        return NULL;
     }
     
-    return ::atoi(conf->arg0().c_str());
-}
-
-SrsConfDirective* SrsConfig::get_forward(string vhost)
-{
-    SrsConfDirective* conf = get_vhost(vhost);
-
-    if (!conf) {
+    SrsConfDirective* enabled = conf->get("enabled");
+    if (!enabled || enabled->arg0() != "on") {
         return NULL;
     }
     
-    return conf->get("forward");
+    return conf->get("on_play");
 }
 
-SrsConfDirective* SrsConfig::get_refer(string vhost)
+SrsConfDirective* SrsConfig::get_vhost_on_stop(string vhost)
 {
     SrsConfDirective* conf = get_vhost(vhost);
 
@@ -1703,52 +1717,38 @@ SrsConfDirective* SrsConfig::get_refer(string vhost)
         return NULL;
     }
     
-    return conf->get("refer");
-}
-
-SrsConfDirective* SrsConfig::get_refer_play(string vhost)
-{
-    SrsConfDirective* conf = get_vhost(vhost);
-
+    conf = conf->get("http_hooks");
     if (!conf) {
         return NULL;
     }
     
-    return conf->get("refer_play");
-}
-
-SrsConfDirective* SrsConfig::get_refer_publish(string vhost)
-{
-    SrsConfDirective* conf = get_vhost(vhost);
-
-    if (!conf) {
+    SrsConfDirective* enabled = conf->get("enabled");
+    if (!enabled || enabled->arg0() != "on") {
         return NULL;
     }
     
-    return conf->get("refer_publish");
+    return conf->get("on_stop");
 }
 
-int SrsConfig::get_chunk_size(const string &vhost)
+SrsConfDirective* SrsConfig::get_vhost_on_dvr_hss_reap_flv(string vhost)
 {
     SrsConfDirective* conf = get_vhost(vhost);
 
     if (!conf) { 
-        return SRS_CONF_DEFAULT_CHUNK_SIZE;
+        return NULL;
     }
     
-    conf = conf->get("chunk_size");
-    if (!conf) {
-        // vhost does not specify the chunk size,
-        // use the global instead.
-        conf = root->get("chunk_size");
+    conf = conf->get("http_hooks");
     if (!conf) {
-            return SRS_CONF_DEFAULT_CHUNK_SIZE;
+        return NULL;
     }
     
-        return ::atoi(conf->arg0().c_str());
+    SrsConfDirective* enabled = conf->get("enabled");
+    if (!enabled || enabled->arg0() != "on") {
+        return NULL;
     }
     
-    return ::atoi(conf->arg0().c_str());
+    return conf->get("on_dvr_hss_reap_flv");
 }
 
 bool SrsConfig::get_bw_check_enabled(const string &vhost)

@@ -422,81 +422,103 @@ public:
     */
     virtual std::vector<SrsConfDirective*>  get_vhosts();
     /**
-    * 
+    * whether vhost is enabled
+    * @param vhost, the vhost name.
+    * @return true when vhost is ok; otherwise, false.
     */
     virtual bool                get_vhost_enabled(std::string vhost);
     /**
-    * 
+    * whether vhost is enabled
+    * @param vhost, the vhost directive.
+    * @return true when vhost is ok; otherwise, false.
     */
     virtual bool                get_vhost_enabled(SrsConfDirective* vhost);
     /**
-    * 
+    * whether gop_cache is enabled of vhost.
+    * gop_cache used to cache last gop, for client to fast startup.
+    * @return true when gop_cache is ok; otherwise, false.
     */
-    virtual SrsConfDirective*   get_vhost_on_connect(std::string vhost);
+    virtual bool                get_gop_cache(std::string vhost);
     /**
-    * 
+    * whether atc is enabled of vhost.
+    * atc always use encoder timestamp, SRS never adjust the time.
+    * @return true when atc is ok; otherwise, false.
     */
-    virtual SrsConfDirective*   get_vhost_on_close(std::string vhost);
+    virtual bool                get_atc(std::string vhost);
     /**
-    * 
+    * whether atc_auto is enabled of vhost.
+    * atc_auto used to auto enable atc, when metadata specified the bravo_atc.
+    * @return true when atc_auto is ok; otherwise, false.
     */
-    virtual SrsConfDirective*   get_vhost_on_publish(std::string vhost);
+    virtual bool                get_atc_auto(std::string vhost);
     /**
-    * 
+    * get the time_jitter algorithm.
+    * @return the time_jitter algorithm, defined in SrsRtmpJitterAlgorithm.
     */
-    virtual SrsConfDirective*   get_vhost_on_unpublish(std::string vhost);
+    virtual int                 get_time_jitter(std::string vhost);
     /**
     * 
     */
-    virtual SrsConfDirective*   get_vhost_on_play(std::string vhost);
+    virtual double              get_queue_length(std::string vhost);
     /**
     * 
     */
-    virtual SrsConfDirective*   get_vhost_on_stop(std::string vhost);
+    virtual SrsConfDirective*   get_refer(std::string vhost);
     /**
     * 
     */
-    virtual SrsConfDirective*   get_vhost_on_dvr_hss_reap_flv(std::string vhost);
+    virtual SrsConfDirective*   get_refer_play(std::string vhost);
     /**
     * 
     */
-    virtual bool                get_gop_cache(std::string vhost);
+    virtual SrsConfDirective*   get_refer_publish(std::string vhost);
     /**
     * 
     */
-    virtual bool                get_atc(std::string vhost);
+    virtual int                 get_chunk_size(const std::string& vhost);
+// forward section
+public:
     /**
     * 
     */
-    virtual bool                get_atc_auto(std::string vhost);
+    virtual SrsConfDirective*   get_forward(std::string vhost);
+// http_hooks section
+public:
     /**
-    * 
+    * get the on_connect callbacks of vhost.
+    * @return the on_connect callback directive, the args is the url to callback.
     */
-    virtual int                 get_time_jitter(std::string vhost);
+    virtual SrsConfDirective*   get_vhost_on_connect(std::string vhost);
     /**
-    * 
+    * get the on_close callbacks of vhost.
+    * @return the on_close callback directive, the args is the url to callback.
     */
-    virtual double              get_queue_length(std::string vhost);
+    virtual SrsConfDirective*   get_vhost_on_close(std::string vhost);
     /**
-    * 
+    * get the on_publish callbacks of vhost.
+    * @return the on_publish callback directive, the args is the url to callback.
     */
-    virtual SrsConfDirective*   get_forward(std::string vhost);
+    virtual SrsConfDirective*   get_vhost_on_publish(std::string vhost);
     /**
-    * 
+    * get the on_unpublish callbacks of vhost.
+    * @return the on_unpublish callback directive, the args is the url to callback.
     */
-    virtual SrsConfDirective*   get_refer(std::string vhost);
+    virtual SrsConfDirective*   get_vhost_on_unpublish(std::string vhost);
     /**
-    * 
+    * get the on_play callbacks of vhost.
+    * @return the on_play callback directive, the args is the url to callback.
     */
-    virtual SrsConfDirective*   get_refer_play(std::string vhost);
+    virtual SrsConfDirective*   get_vhost_on_play(std::string vhost);
     /**
-    * 
+    * get the on_stop callbacks of vhost.
+    * @return the on_stop callback directive, the args is the url to callback.
     */
-    virtual SrsConfDirective*   get_refer_publish(std::string vhost);
+    virtual SrsConfDirective*   get_vhost_on_stop(std::string vhost);
     /**
-    * 
+    * get the on_dvr_hss_reap_flv callbacks of vhost.
+    * @return the on_dvr_hss_reap_flv callback directive, the args is the url to callback.
     */
-    virtual int                 get_chunk_size(const std::string& vhost);
+    virtual SrsConfDirective*   get_vhost_on_dvr_hss_reap_flv(std::string vhost);
 // bwct(bandwidth check tool) section
 public:
     /**