pci: add String() method to pci.Device

We have AddressFromString(), so it seems natural to add the symmetric, which we can also use in few places internally to make the code more readable. Signed-off-by: Francesco Romani <[email protected]>
jaypipes · Feb 4, 2021 · 6a73eaa · 6a73eaa
1 parent 55f240f
commit 6a73eaa
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Showing 3 changed files with 23 additions and 1 deletion.
diff --git a/pkg/pci/pci.go b/pkg/pci/pci.go
@@ -144,6 +144,11 @@ type Address struct {
 	Function string
 }
 
+// String() returns the canonical [D]BSF representation of this Address
+func (addr *Address) String() string {
+	return addr.Domain + ":" + addr.Bus + ":" + addr.Slot + "." + addr.Function
+}
+
 // Given a string address, returns a complete Address struct, filled in with
 // domain, bus, slot and function components. The address string may either
 // be in $BUS:$SLOT.$FUNCTION (BSF) format or it can be a full PCI address

diff --git a/pkg/pci/pci_linux.go b/pkg/pci/pci_linux.go
@@ -52,7 +52,7 @@ func getDeviceRevision(ctx *context.Context, address string) string {
 	}
 	revisionPath := filepath.Join(
 		paths.SysBusPciDevices,
-		pciAddr.Domain+":"+pciAddr.Bus+":"+pciAddr.Slot+"."+pciAddr.Function,
+		pciAddr.String(),
 		"revision",
 	)
 

diff --git a/pkg/pci/pci_test.go b/pkg/pci/pci_test.go
@@ -9,6 +9,7 @@ package pci_test
 import (
 	"os"
 	"reflect"
+	"strings"
 	"testing"
 
 	"github.com/jaypipes/ghw/pkg/context"
@@ -21,6 +22,11 @@ func TestPCIAddressFromString(t *testing.T) {
 	tests := []struct {
 		addrStr  string
 		expected *pci.Address
+		// AddressFromString is more flexible than String() and wants
+		// to accept addresses not in full canonical form, as long as
+		// it can do the right thing - e.g. a sane default Domain exists.
+		// Thus we need to sometimes skip the Address -> string check.
+		skipStringTest bool
 	}{
 		{
 			addrStr: "00:00.0",
@@ -30,6 +36,7 @@ func TestPCIAddressFromString(t *testing.T) {
 				Slot:     "00",
 				Function: "0",
 			},
+			skipStringTest: true,
 		},
 		{
 			addrStr: "0000:00:00.0",
@@ -64,6 +71,16 @@ func TestPCIAddressFromString(t *testing.T) {
 		if !reflect.DeepEqual(got, test.expected) {
 			t.Fatalf("Test #%d failed. Expected %v but got %v", x, test.expected, got)
 		}
+
+		if test.skipStringTest {
+			continue
+		}
+
+		addrStr := got.String()
+		// addresses are case insensitive
+		if !strings.EqualFold(addrStr, test.addrStr) {
+			t.Fatalf("Test #%d failed. Expected %q but got %q (case insensitive match)", x, test.addrStr, addrStr)
+		}
 	}
 }