main: add make coverage_server build option (pingcap#11844)

Makefile

@@ -11,10 +11,11 @@ CURDIR := $(shell pwd)
 path_to_add := $(addsuffix /bin,$(subst :,/bin:,$(GOPATH))):$(PWD)/tools/bin
 export PATH := $(path_to_add):$(PATH)
 
-GO        := GO111MODULE=on go
-GOBUILD   := CGO_ENABLED=1 $(GO) build $(BUILD_FLAG) -tags codes
-GOTEST    := CGO_ENABLED=1 $(GO) test -p 4
-OVERALLS  := CGO_ENABLED=1 GO111MODULE=on overalls
+GO              := GO111MODULE=on go
+GOBUILD         := CGO_ENABLED=1 $(GO) build $(BUILD_FLAG) -tags codes
+GOBUILDCOVERAGE := GOPATH=$(GOPATH) CGO_ENABLED=1 cd tidb-server; $(GO) test -coverpkg="../..." -c .
+GOTEST          := CGO_ENABLED=1 $(GO) test -p 4
+OVERALLS        := CGO_ENABLED=1 GO111MODULE=on overalls
 
 ARCH      := "`uname -s`"
 LINUX     := "Linux"
@@ -34,6 +35,7 @@ LDFLAGS += -X "github.com/pingcap/tidb/util/printer.TiDBGitBranch=$(shell git re
 LDFLAGS += -X "github.com/pingcap/tidb/util/printer.GoVersion=$(shell go version)"
 
 TEST_LDFLAGS =  -X "github.com/pingcap/tidb/config.checkBeforeDropLDFlag=1"
+COVERAGE_SERVER_LDFLAGS =  -X "github.com/pingcap/tidb/tidb-server.isCoverageServer=1"
 
 CHECK_LDFLAGS += $(LDFLAGS) ${TEST_LDFLAGS}
 
@@ -187,6 +189,13 @@ else
 	$(GOBUILD) $(RACE_FLAG) -ldflags '$(CHECK_LDFLAGS)' -o '$(TARGET)' tidb-server/main.go
 endif
 
+coverage_server:
+ifeq ($(TARGET), "")
+	$(GOBUILDCOVERAGE) $(RACE_FLAG) -ldflags '$(LDFLAGS) $(COVERAGE_SERVER_LDFLAGS) $(CHECK_FLAG)' -o ../bin/tidb-coverage-server
+else
+	$(GOBUILDCOVERAGE) $(RACE_FLAG) -ldflags '$(LDFLAGS) $(COVERAGE_SERVER_LDFLAGS) $(CHECK_FLAG)' -o '$(TARGET)'
+endif
+
 benchkv:
 	$(GOBUILD) -ldflags '$(LDFLAGS)' -o bin/benchkv cmd/benchkv/main.go
 

tidb-server/main.go

@@ -178,15 +178,19 @@ func main() {
 	signal.SetupSignalHandler(serverShutdown)
 	runServer()
 	cleanup()
-	exit()
+	syncLog()
 }
 
 func exit() {
+	syncLog()
+	os.Exit(0)
+}
+
+func syncLog() {
 	if err := log.Sync(); err != nil {
 		fmt.Fprintln(os.Stderr, "sync log err:", err)
 		os.Exit(1)
 	}
-	os.Exit(0)
 }
 
 func setCPUAffinity() {

tidb-server/main_test.go

@@ -0,0 +1,26 @@
+// Copyright 2019 PingCAP, Inc.
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//     http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+package main
+
+import "testing"
+
+var isCoverageServer = "0"
+
+// TestRunMain is a dummy test case, which contains only the main function of tidb-server,
+// and it is used to generate coverage_server.
+func TestRunMain(t *testing.T) {
+	if isCoverageServer == "1" {
+		main()
+	}
+}