for #179, add dvr plan append.

@@ -284,6 +284,7 @@ vhost dvr.srs.com {
         # the dvr plan. canbe:
         #       session reap flv when session end(unpublish).
         #       segment reap flv when flv duration exceed the specified dvr_duration.
+        #       append always append to flv file, never reap it.
         #       api reap flv when api required.
         # default: session
         dvr_plan        session;

@@ -60,6 +60,7 @@ CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
 #define SRS_CONF_DEFAULT_DVR_PATH "./objs/nginx/html"
 #define SRS_CONF_DEFAULT_DVR_PLAN_SESSION "session"
 #define SRS_CONF_DEFAULT_DVR_PLAN_SEGMENT "segment"
+#define SRS_CONF_DEFAULT_DVR_PLAN_APPEND "append"
 #define SRS_CONF_DEFAULT_DVR_PLAN_API "api"
 #define SRS_CONF_DEFAULT_DVR_PLAN SRS_CONF_DEFAULT_DVR_PLAN_SESSION
 #define SRS_CONF_DEFAULT_DVR_DURATION 30

@@ -86,7 +86,7 @@ bool SrsFlvSegment::is_overflow(int64_t max_duration)
     return duration >= max_duration;
 }
 
-int SrsFlvSegment::open()
+int SrsFlvSegment::open(bool use_tmp_file)
 {
     int ret = ERROR_SUCCESS;
     
@@ -113,7 +113,7 @@ int SrsFlvSegment::open()
     }
     
     // generate the tmp flv path.
-    if (!fresh_flv_file) {
+    if (!fresh_flv_file || !use_tmp_file) {
         // when path exists, always append to it.
         // so we must use the target flv path as output flv.
         tmp_flv_file = path;
@@ -546,8 +546,11 @@ SrsDvrPlan* SrsDvrPlan::create_plan(string vhost)
         return new SrsDvrSegmentPlan();
     } else if (plan == SRS_CONF_DEFAULT_DVR_PLAN_SESSION) {
         return new SrsDvrSessionPlan();
+    } else if (plan == SRS_CONF_DEFAULT_DVR_PLAN_APPEND) {
+        return new SrsDvrAppendPlan();
     } else {
-        return new SrsDvrSessionPlan();
+        srs_error("invalid dvr plan=%s, vhost=%s", plan.c_str(), vhost.c_str());
+        srs_assert(false);
     }
 }
 
@@ -601,6 +604,40 @@ void SrsDvrSessionPlan::on_unpublish()
     dvr_enabled = false;
 }
 
+SrsDvrAppendPlan::SrsDvrAppendPlan()
+{
+}
+
+SrsDvrAppendPlan::~SrsDvrAppendPlan()
+{
+}
+
+int SrsDvrAppendPlan::on_publish()
+{
+    int ret = ERROR_SUCCESS;
+    
+    // support multiple publish.
+    if (dvr_enabled) {
+        return ret;
+    }
+
+    if (!_srs_config->get_dvr_enabled(req->vhost)) {
+        return ret;
+    }
+
+    if ((ret = segment->open(false)) != ERROR_SUCCESS) {
+        return ret;
+    }
+
+    dvr_enabled = true;
+
+    return ret;
+}
+
+void SrsDvrAppendPlan::on_unpublish()
+{
+}
+
 SrsDvrSegmentPlan::SrsDvrSegmentPlan()
 {
     segment_duration = -1;

@@ -113,8 +113,9 @@ public:
     /**
     * open new segment file, timestamp start at 0 for fresh flv file.
     * @remark ignore when already open.
+    * @param use_tmp_file whether use tmp file if possible.
     */
-    virtual int open();
+    virtual int open(bool use_tmp_file = true);
     /**
     * close current segment.
     * @remark ignore when already closed.
@@ -208,6 +209,19 @@ public:
 };
 
 /**
+* always append to flv file, never reap it.
+*/
+class SrsDvrAppendPlan : public SrsDvrPlan
+{
+public:
+    SrsDvrAppendPlan();
+    virtual ~SrsDvrAppendPlan();
+public:
+    virtual int on_publish();
+    virtual void on_unpublish();
+};
+
+/**
 * segment plan: reap flv when duration exceed.
 */
 class SrsDvrSegmentPlan : public SrsDvrPlan