Initial version of a go version of the compiler wrapper.

Still calls the old wrapper if one of the following flags is given:
- Xclang-path
- clang-syntax
- env WITH_TIDY
- env FORCE_DISABLE_WERROR
- env GETRUSAGE
- env BISECT_STAGE

BUG=chromium:773875
TEST=Unit tests that also verify the produced command against the
TEST=existing compiler wrapper.

Change-Id: I1e0a720ce9f485d8015deefb2682f2cb760d82e4
Reviewed-on: https://chromium-review.googlesource.com/c/chromiumos/third_party/toolchain-utils/+/1652057
Reviewed-by: Manoj Gupta <manojgupta@chromium.org>
Reviewed-by: Tobias Bosch <tbosch@google.com>
Reviewed-by: George Burgess <gbiv@chromium.org>
Tested-by: Tobias Bosch <tbosch@google.com>
Legacy-Commit-Queue: Commit Bot <commit-bot@chromium.org>

1 files changed, 37 insertions, 0 deletions

diff --git a/compiler_wrapper/env.go b/compiler_wrapper/env.go
new file mode 100644
index 00000000..3c106d4a
--- /dev/null
+++ b/compiler_wrapper/env.go
@@ -0,0 +1,37 @@
+package main
+
+import (
+	"os"
+)
+
+type env interface {
+	getenv(key string) string
+	environ() []string
+	getwd() string
+}
+
+type processEnv struct {
+	wd string
+}
+
+func newProcessEnv() (env, error) {
+	wd, err := os.Getwd()
+	if err != nil {
+		return nil, err
+	}
+	return &processEnv{wd: wd}, nil
+}
+
+var _ env = (*processEnv)(nil)
+
+func (env *processEnv) getenv(key string) string {
+	return os.Getenv(key)
+}
+
+func (env *processEnv) environ() []string {
+	return os.Environ()
+}
+
+func (env *processEnv) getwd() string {
+	return env.wd
+}