compiler_wrapper: add working dir to rusage logs

Adds current working directory as a new field in rusage logs.
This is useful for determining what package was being compiled.

BUG=chromium:1156314
TEST=Modified and ran unit tests

Change-Id: I58d7040c90fbd7d9b81532d0114862cbf4b23f88
Reviewed-on: https://chromium-review.googlesource.com/c/chromiumos/third_party/toolchain-utils/+/2636450
Tested-by: Ryan Beltran <ryanbeltran@chromium.org>
Reviewed-by: George Burgess <gbiv@chromium.org>

2 files changed, 29 insertions, 14 deletions

diff --git a/compiler_wrapper/rusage_flag.go b/compiler_wrapper/rusage_flag.go
index 31ff0d10..c6f887d7 100644
--- a/compiler_wrapper/rusage_flag.go
+++ b/compiler_wrapper/rusage_flag.go
@@ -39,13 +39,14 @@ func lockFileExclusive(fd uintptr) error {
 }
 
 type rusageLog struct {
-	ExitCode        int      `json:"exit_code"`
-	ElapsedRealTime float64  `json:"elapsed_real_time"`
-	ElapsedUserTime float64  `json:"elapsed_user_time"`
-	ElapsedSysTime  float64  `json:"elapsed_sys_time"`
-	MaxMemUsed      int64    `json:"max_mem_used"`
-	Compiler        string   `json:"compiler"`
-	CompilerArgs    []string `json:"compiler_args"`
+	ExitCode         int      `json:"exit_code"`
+	ElapsedRealTime  float64  `json:"elapsed_real_time"`
+	ElapsedUserTime  float64  `json:"elapsed_user_time"`
+	ElapsedSysTime   float64  `json:"elapsed_sys_time"`
+	MaxMemUsed       int64    `json:"max_mem_used"`
+	Compiler         string   `json:"compiler"`
+	CompilerArgs     []string `json:"compiler_args"`
+	WorkingDirectory string   `json:"working_directory"`
 }
 
 func logRusage(env env, logFileName string, compilerCmd *command) (exitCode int, err error) {
@@ -87,14 +88,21 @@ func logRusage(env env, logFileName string, compilerCmd *command) (exitCode int,
 
 	timeUnit := float64(time.Second)
 
+	// We want to know what package is being compiled. The working directory gives us a good clue.
+	cwd, err := os.Getwd()
+	if err != nil {
+		return 0, wrapErrorwithSourceLocf(err, "error getting working directory for rusage log")
+	}
+
 	logEntry := rusageLog{
-		ExitCode:        exitCode,
-		ElapsedRealTime: float64(elapsedRealTime) / timeUnit,
-		ElapsedUserTime: float64(elapsedUserTime) / timeUnit,
-		ElapsedSysTime:  float64(elapsedSysTime) / timeUnit,
-		MaxMemUsed:      maxMemUsed,
-		Compiler:        absCompilerPath,
-		CompilerArgs:    compilerCmd.Args,
+		ExitCode:         exitCode,
+		ElapsedRealTime:  float64(elapsedRealTime) / timeUnit,
+		ElapsedUserTime:  float64(elapsedUserTime) / timeUnit,
+		ElapsedSysTime:   float64(elapsedSysTime) / timeUnit,
+		MaxMemUsed:       maxMemUsed,
+		Compiler:         absCompilerPath,
+		CompilerArgs:     compilerCmd.Args,
+		WorkingDirectory: cwd,
 	}
 
 	// Note: using file mode 0666 so that a root-created log is writable by others.
diff --git a/compiler_wrapper/rusage_flag_test.go b/compiler_wrapper/rusage_flag_test.go
index 0736c757..940f4a79 100644
--- a/compiler_wrapper/rusage_flag_test.go
+++ b/compiler_wrapper/rusage_flag_test.go
@@ -105,6 +105,13 @@ func TestLogRusageFileContent(t *testing.T) {
 		if matched, _ := regexp.MatchString("--sysroot=.*", rlog.CompilerArgs[0]); !matched {
 			t.Errorf("unexpected compiler args. Got: %s", rlog.CompilerArgs)
 		}
+		cwd, err := os.Getwd()
+		if err != nil {
+			t.Fatalf("Failed to get current working directory: %v", err)
+		}
+		if rlog.WorkingDirectory != cwd {
+			t.Errorf("Unexpected working directory. Got: %q, Want: %q", rlog.WorkingDirectory, cwd)
+		}
 	})
 }