pkg/build: refactor Image function arguments

Image takes too many arguments, so we need to do lots of forwarding,
adding new argumnets is painful and most OSes are not interested
in lots of arguments.
Combine all arguments into a params struct.

1 files changed, 21 insertions, 23 deletions

diff --git a/pkg/build/linux.go b/pkg/build/linux.go
index 3c1051ff9..aafb33867 100644
--- a/pkg/build/linux.go
+++ b/pkg/build/linux.go
@@ -22,21 +22,19 @@ import (
 
 type linux struct{}
 
-func (linux linux) build(targetArch, vmType, kernelDir, outputDir, compiler, userspaceDir,
-	cmdlineFile, sysctlFile string, config []byte) error {
-	if err := linux.buildKernel(targetArch, kernelDir, outputDir, compiler, config); err != nil {
+func (linux linux) build(params *Params) error {
+	if err := linux.buildKernel(params); err != nil {
 		return err
 	}
-	if err := linux.createImage(targetArch, vmType, kernelDir, outputDir, userspaceDir, cmdlineFile,
-		sysctlFile); err != nil {
+	if err := linux.createImage(params); err != nil {
 		return err
 	}
 	return nil
 }
 
-func (linux) buildKernel(targetArch, kernelDir, outputDir, compiler string, config []byte) error {
-	configFile := filepath.Join(kernelDir, ".config")
-	if err := osutil.WriteFile(configFile, config); err != nil {
+func (linux) buildKernel(params *Params) error {
+	configFile := filepath.Join(params.KernelDir, ".config")
+	if err := osutil.WriteFile(configFile, params.Config); err != nil {
 		return fmt.Errorf("failed to write config file: %v", err)
 	}
 	if err := osutil.SandboxChown(configFile); err != nil {
@@ -45,34 +43,34 @@ func (linux) buildKernel(targetArch, kernelDir, outputDir, compiler string, conf
 	// One would expect olddefconfig here, but olddefconfig is not present in v3.6 and below.
 	// oldconfig is the same as olddefconfig if stdin is not set.
 	// Note: passing in compiler is important since 4.17 (at the very least it's noted in the config).
-	if err := runMake(kernelDir, "oldconfig", "CC="+compiler); err != nil {
+	if err := runMake(params.KernelDir, "oldconfig", "CC="+params.Compiler); err != nil {
 		return err
 	}
 	// Write updated kernel config early, so that it's captured on build failures.
-	outputConfig := filepath.Join(outputDir, "kernel.config")
+	outputConfig := filepath.Join(params.OutputDir, "kernel.config")
 	if err := osutil.CopyFile(configFile, outputConfig); err != nil {
 		return err
 	}
 	// We build only zImage/bzImage as we currently don't use modules.
 	var target string
-	switch targetArch {
+	switch params.TargetArch {
 	case "386", "amd64":
 		target = "bzImage"
 	case "ppc64le":
 		target = "zImage"
 	}
-	if err := runMake(kernelDir, target, "CC="+compiler); err != nil {
+	if err := runMake(params.KernelDir, target, "CC="+params.Compiler); err != nil {
 		return err
 	}
-	vmlinux := filepath.Join(kernelDir, "vmlinux")
-	outputVmlinux := filepath.Join(outputDir, "obj", "vmlinux")
+	vmlinux := filepath.Join(params.KernelDir, "vmlinux")
+	outputVmlinux := filepath.Join(params.OutputDir, "obj", "vmlinux")
 	if err := osutil.Rename(vmlinux, outputVmlinux); err != nil {
 		return fmt.Errorf("failed to rename vmlinux: %v", err)
 	}
 	return nil
 }
 
-func (linux) createImage(targetArch, vmType, kernelDir, outputDir, userspaceDir, cmdlineFile, sysctlFile string) error {
+func (linux) createImage(params *Params) error {
 	tempDir, err := ioutil.TempDir("", "syz-build")
 	if err != nil {
 		return err
@@ -84,30 +82,30 @@ func (linux) createImage(targetArch, vmType, kernelDir, outputDir, userspaceDir,
 	}
 
 	var kernelImage string
-	switch targetArch {
+	switch params.TargetArch {
 	case "386", "amd64":
 		kernelImage = "arch/x86/boot/bzImage"
 	case "ppc64le":
 		kernelImage = "arch/powerpc/boot/zImage.pseries"
 	}
-	kernelImagePath := filepath.Join(kernelDir, filepath.FromSlash(kernelImage))
-	cmd := osutil.Command(scriptFile, userspaceDir, kernelImagePath, targetArch)
+	kernelImagePath := filepath.Join(params.KernelDir, filepath.FromSlash(kernelImage))
+	cmd := osutil.Command(scriptFile, params.UserspaceDir, kernelImagePath, params.TargetArch)
 	cmd.Dir = tempDir
 	cmd.Env = append([]string{}, os.Environ()...)
 	cmd.Env = append(cmd.Env,
-		"SYZ_VM_TYPE="+vmType,
-		"SYZ_CMDLINE_FILE="+osutil.Abs(cmdlineFile),
-		"SYZ_SYSCTL_FILE="+osutil.Abs(sysctlFile),
+		"SYZ_VM_TYPE="+params.VMType,
+		"SYZ_CMDLINE_FILE="+osutil.Abs(params.CmdlineFile),
+		"SYZ_SYSCTL_FILE="+osutil.Abs(params.SysctlFile),
 	)
 	if _, err = osutil.Run(time.Hour, cmd); err != nil {
 		return fmt.Errorf("image build failed: %v", err)
 	}
 	// Note: we use CopyFile instead of Rename because src and dst can be on different filesystems.
-	imageFile := filepath.Join(outputDir, "image")
+	imageFile := filepath.Join(params.OutputDir, "image")
 	if err := osutil.CopyFile(filepath.Join(tempDir, "disk.raw"), imageFile); err != nil {
 		return err
 	}
-	keyFile := filepath.Join(outputDir, "key")
+	keyFile := filepath.Join(params.OutputDir, "key")
 	if err := osutil.CopyFile(filepath.Join(tempDir, "key"), keyFile); err != nil {
 		return err
 	}