print git version string to console and logfile when server start up.

git version string example:2.0+ r3504M 6bf24238 2017-02-28 19:10:44
which means: branch , revison index, commit hash, date time

@@ -348,6 +348,7 @@ else
     cat << END >> ${SRS_WORKDIR}/${SRS_MAKEFILE}
 server: _prepare_dir
 	@echo "build the srs(simple rtmp server) over st(state-threads)"
+	./scripts/version.sh
 	\$(MAKE) -f ${SRS_OBJS_DIR}/${SRS_MAKEFILE} srs
 srs_ingest_hls: _prepare_dir
 	@echo "build the srs_ingest_hls for srs"

+#ifndef VERSION_H
+#define VERSION_H
+ 
+#define VERSION_STRING $FULL_VERSION
+ 
+#endif

+#!/bin/bash
+rm -f src/version.h
+git rev-list HEAD | sort > git_rev_list
+LOCALVER=`wc -l git_rev_list | awk '{print $1}'`
+BRANCH=$(git branch | grep "\*" | awk '{print $2}')
+echo branch:$BRANCH
+if [ $LOCALVER -ge 1 ] ; then
+    VER=${LOCALVER}
+    if git status | grep -q "modified:" ; then
+        VER="${VER}M"
+    fi
+    GIT_VERSION="$BRANCH r$VER $(git rev-list HEAD -n 1 | cut -c 1-8)"
+else
+    GIT_VERSION="$BRANCH none"
+fi
+rm -f git_rev_list
+
+GIT_VERSION="${GIT_VERSION} $(date "+%Y-%m-%d %H:%M:%S")"
+ 
+cat scripts/version.h.tmpl | sed "s/\$FULL_VERSION/\"$GIT_VERSION\"/g" > objs/version.h
+ 
+echo "save to version.h:$GIT_VERSION"

@@ -46,11 +46,12 @@ using namespace std;
 #include <srs_kernel_file.hpp>
 #include <srs_app_utility.hpp>
 #include <srs_core_performance.hpp>
+#include "../../objs/version.h"
 
 using namespace _srs_internal;
 
 // the version to identify the core.
-const char* _srs_version = "XCORE-"RTMP_SIG_SRS_SERVER;
+const char* _srs_version = "XCORE-"RTMP_SIG_SRS_SERVER": "VERSION_STRING;
 
 #define SRS_WIKI_URL_LOG "https://github.com/ossrs/srs/wiki/v1_CN_SrsLog"
 
@@ -1552,6 +1553,9 @@ int SrsConfig::check_config()
 {
     int ret = ERROR_SUCCESS;
 
+    //output _srs_version to log
+    srs_trace(_srs_version);
+
     srs_trace("srs checking config...");
 
     ////////////////////////////////////////////////////////////////////////