pkg/csource: refactor

csource.go is too large and messy.
Move Build/Format into buid.go.
Move generation of common header into common.go.
Split generation of common header into smaller managable functions.

1 files changed, 86 insertions, 0 deletions

diff --git a/pkg/csource/build.go b/pkg/csource/build.go
new file mode 100644
index 000000000..a059dcaf8
--- /dev/null
+++ b/pkg/csource/build.go
@@ -0,0 +1,86 @@
+// Copyright 2017 syzkaller project authors. All rights reserved.
+// Use of this source code is governed by Apache 2 LICENSE that can be found in the LICENSE file.
+
+package csource
+
+import (
+	"bytes"
+	"errors"
+	"fmt"
+	"io/ioutil"
+	"os"
+	"os/exec"
+
+	"github.com/google/syzkaller/pkg/osutil"
+	"github.com/google/syzkaller/prog"
+	"github.com/google/syzkaller/sys/targets"
+)
+
+// Build builds a C/C++ program from source src and returns name of the resulting binary.
+// lang can be "c" or "c++".
+func Build(target *prog.Target, lang, src string) (string, error) {
+	bin, err := ioutil.TempFile("", "syzkaller")
+	if err != nil {
+		return "", fmt.Errorf("failed to create temp file: %v", err)
+	}
+	bin.Close()
+	sysTarget := targets.List[target.OS][target.Arch]
+	compiler := sysTarget.CCompilerPrefix + "gcc"
+	if _, err := exec.LookPath(compiler); err != nil {
+		return "", NoCompilerErr
+	}
+	flags := []string{
+		"-x", lang, "-Wall", "-Werror", "-O1", "-g", "-o", bin.Name(),
+		src, "-pthread",
+	}
+	flags = append(flags, sysTarget.CrossCFlags...)
+	if sysTarget.PtrSize == 4 {
+		// We do generate uint64's for syscall arguments that overflow longs on 32-bit archs.
+		flags = append(flags, "-Wno-overflow")
+	}
+	out, err := osutil.Command(compiler, append(flags, "-static")...).CombinedOutput()
+	if err != nil {
+		// Some distributions don't have static libraries.
+		out, err = osutil.Command(compiler, flags...).CombinedOutput()
+	}
+	if err != nil {
+		os.Remove(bin.Name())
+		data, _ := ioutil.ReadFile(src)
+		return "", fmt.Errorf("failed to build program:\n%s\n%s\ncompiler invocation: %v %v\n",
+			data, out, compiler, flags)
+	}
+	return bin.Name(), nil
+}
+
+var NoCompilerErr = errors.New("no target compiler")
+
+// Format reformats C source using clang-format.
+func Format(src []byte) ([]byte, error) {
+	stdout, stderr := new(bytes.Buffer), new(bytes.Buffer)
+	cmd := osutil.Command("clang-format", "-assume-filename=/src.c", "-style", style)
+	cmd.Stdin = bytes.NewReader(src)
+	cmd.Stdout = stdout
+	cmd.Stderr = stderr
+	if err := cmd.Run(); err != nil {
+		return src, fmt.Errorf("failed to format source: %v\n%v", err, stderr.String())
+	}
+	return stdout.Bytes(), nil
+}
+
+// Something acceptable for kernel developers and email-friendly.
+var style = `{
+BasedOnStyle: LLVM,
+IndentWidth: 2,
+UseTab: Never,
+BreakBeforeBraces: Linux,
+IndentCaseLabels: false,
+DerivePointerAlignment: false,
+PointerAlignment: Left,
+AlignTrailingComments: true,
+AllowShortBlocksOnASingleLine: false,
+AllowShortCaseLabelsOnASingleLine: false,
+AllowShortFunctionsOnASingleLine: false,
+AllowShortIfStatementsOnASingleLine: false,
+AllowShortLoopsOnASingleLine: false,
+ColumnLimit: 72,
+}`