Merge pull request #3 from maximumadmin/arm-fix-and-build-improvements

Arm fix and build improvements

Makefile

@@ -18,13 +18,29 @@ build:
 	go build -v -o $(OUT_FILE) $(GO_FILE)
 	@ls -lh $(OUT_FILE)
 
-# Build production binary.
+# Build statically linked production binary.
 release: clean
 	@{\
-		LD_FLAGS="-s -w" ;\
-		CGO_ENABLED=0 go build -v -a -trimpath \
-			-ldflags "$$LD_FLAGS" \
-			-o $(OUT_FILE) $(GO_FILE) ;\
+		export GOFLAGS="-a -trimpath -ldflags=-w -ldflags=-s" ;\
+		if [ "$${GOARCH}" != "arm" ]; then \
+			export GOFLAGS="$${GOFLAGS} -buildmode=pie" ;\
+		fi ;\
+		CGO_ENABLED=0 go build -o $(OUT_FILE) $(GO_FILE) ;\
+	}
+	@ls -lh $(OUT_FILE)
+
+# Build dinamically linked production binary.
+release-dynamic: clean
+	@{\
+		export CGO_CPPFLAGS="$${CPPFLAGS}" ;\
+		export CGO_CFLAGS="$${CFLAGS}" ;\
+		export CGO_CXXFLAGS="$${CXXFLAGS}" ;\
+		export CGO_LDFLAGS="$${LDFLAGS}" ;\
+		export GOFLAGS="-a -trimpath -ldflags=-linkmode=external -ldflags=-w -ldflags=-s" ;\
+		if [ "$${GOARCH}" != "arm" ]; then \
+			export GOFLAGS="$${GOFLAGS} -buildmode=pie" ;\
+		fi ;\
+		go build -o $(OUT_FILE) $(GO_FILE) ;\
 	}
 	@ls -lh $(OUT_FILE)
 

README.md

@@ -14,7 +14,7 @@ See also https://fedoraproject.org/wiki/Changes/SwapOnZRAM#Benefit_to_Fedora
 ## Compiling
 
 * Install `go`, this depends on the distribution you are using e.g. for Ubuntu the command should be `sudo apt-get install golang`.
-* Run `make release`
+* Run `make release` to make a x86_64 build, to make an ARM build (i.e. for the Raspberry Pi) run `GOOS=linux GOARCH=arm GOARM=7 make release`
 * A new executable called `zramd.bin` will be created in the current directory, now you can uninstall `go` if you like.
 * Optionally on distributions using systemd, you can install `zramd` by just running `make install`, see below for additional installation methods.
 

src/utsname/utsname.go

@@ -24,30 +24,22 @@ func (uname *UTSName) KernelVersion() (int, int) {
 	return int(major), int(minor)
 }
 
-func parseInt8(data []int8) string {
-	b := make([]byte, 0, len(data))
-	for _, v := range data {
-		if v == 0x00 {
-			break
-		}
-		b = append(b, byte(v))
-	}
-	return string(b)
-}
-
 // Uname returns information about the current kernel.
 func Uname() *UTSName {
 	var uname syscall.Utsname
 	err := syscall.Uname(&uname)
 	if err != nil {
 		panic(err)
 	}
+	// Keep in mind that we are using 2 sightly different implementations to parse
+	// char slices as they use different data types depending on the architecture,
+	// see also https://github.com/golang/go/issues/13318.
 	return &UTSName{
-		SysName:    parseInt8(uname.Sysname[:]),
-		NodeName:   parseInt8(uname.Nodename[:]),
-		Release:    parseInt8(uname.Release[:]),
-		Version:    parseInt8(uname.Version[:]),
-		Machine:    parseInt8(uname.Machine[:]),
-		DomainName: parseInt8(uname.Domainname[:]),
+		SysName:    parseCharSlice(uname.Sysname[:]),
+		NodeName:   parseCharSlice(uname.Nodename[:]),
+		Release:    parseCharSlice(uname.Release[:]),
+		Version:    parseCharSlice(uname.Version[:]),
+		Machine:    parseCharSlice(uname.Machine[:]),
+		DomainName: parseCharSlice(uname.Domainname[:]),
 	}
 }

src/utsname/utsname_amd64.go

@@ -0,0 +1,12 @@
+package utsname
+
+func parseCharSlice(data []int8) string {
+	b := make([]byte, 0, len(data))
+	for _, v := range data {
+		if v == 0x00 {
+			break
+		}
+		b = append(b, byte(v))
+	}
+	return string(b)
+}

src/utsname/utsname_arm.go

@@ -0,0 +1,12 @@
+package utsname
+
+func parseCharSlice(data []uint8) string {
+	b := make([]byte, 0, len(data))
+	for _, v := range data {
+		if v == 0x00 {
+			break
+		}
+		b = append(b, byte(v))
+	}
+	return string(b)
+}