Add version API to ECP shared library.

build/scripts/darwin_amd64.sh

@@ -13,7 +13,9 @@
 # See the License for the specific language governing permissions and
 # limitations under the License.
 
-set -eu
+set -eux
+
+CURRENT_TAG=$(git tag --sort v:refname | tail -n 1)
 
 # Create a folder to hold the binaries
 rm -rf ./build/bin/darwin_amd64
@@ -26,5 +28,5 @@ mv darwin ./../../../build/bin/darwin_amd64/ecp
 cd ./../../..
 
 # Build the signer library
-go build -buildmode=c-shared -o build/bin/darwin_amd64/libecp.dylib cshared/main.go
+go build -buildmode=c-shared -buildmode=c-shared -ldflags="-X=main.Version=$CURRENT_TAG" -o build/bin/darwin_amd64/libecp.dylib cshared/main.go
 rm build/bin/darwin_amd64/libecp.h

build/scripts/darwin_arm64.sh

@@ -13,7 +13,9 @@
 # See the License for the specific language governing permissions and
 # limitations under the License.
 
-set -eu
+set -eux
+
+CURRENT_TAG=$(git tag --sort v:refname | tail -n 1)
 
 # Create a folder to hold the binaries
 rm -rf ./build/bin/darwin_arm64
@@ -26,5 +28,5 @@ mv darwin ./../../../build/bin/darwin_arm64/ecp
 cd ./../../..
 
 # Build the signer library
-CGO_ENABLED=1 GO111MODULE=on GOARCH=arm64 go build -buildmode=c-shared -o build/bin/darwin_arm64/libecp.dylib cshared/main.go
+CGO_ENABLED=1 GO111MODULE=on GOARCH=arm64 go build -buildmode=c-shared -ldflags="-X=main.Version=$CURRENT_TAG" -o build/bin/darwin_arm64/libecp.dylib cshared/main.go
 rm build/bin/darwin_arm64/libecp.h

build/scripts/linux_amd64.sh

@@ -13,12 +13,16 @@
 # See the License for the specific language governing permissions and
 # limitations under the License.
 
+set -eux
+
+CURRENT_TAG=$(git tag --sort v:refname | tail -n 1)
+
 # Create a folder to hold the binaries
 rm -rf ./build/bin/linux_amd64
 mkdir -p ./build/bin/linux_amd64
 
 # Build the signer library
-go build -buildmode=c-shared -o build/bin/linux_amd64/libecp.so cshared/main.go
+go build -buildmode=c-shared -ldflags="-X=main.Version=$CURRENT_TAG" -o build/bin/linux_amd64/libecp.so cshared/main.go
 rm build/bin/linux_amd64/libecp.h
 
 # Build the signer binary

build/scripts/windows_amd64.ps1

@@ -27,5 +27,6 @@ Move-Item .\windows.exe ..\..\..\build\bin\windows_amd64\ecp.exe
 Set-Location ..\..\..\
 
 # Build the signer library
+# TODO: Add build version to shared DLL. https://github.com/googleapis/enterprise-certificate-proxy/issues/103
 go build -buildmode=c-shared -o .\build\bin\windows_amd64\libecp.dll .\cshared\main.go
 Remove-Item .\build\bin\windows_amd64\libecp.h

cshared/main.go

@@ -39,6 +39,8 @@ import (
 	"github.com/googleapis/enterprise-certificate-proxy/client"
 )
 
+var Version = "dev"
+
 // If ECP Logging is enabled return true
 // Otherwise return false
 func enableECPLogging() bool {
@@ -71,6 +73,13 @@ func getCertPem(configFilePath string) []byte {
 	return certChainPem
 }
 
+// Returns ECP's version number.
+//
+//export ECPVersion
+func ECPVersion() *C.char {
+	return C.CString(Version)
+}
+
 // GetCertPemForPython reads the contents of the certificate specified by configFilePath,
 // storing the result inside a certHolder byte array of size certHolderLen.
 //