Improve shim debug logging

- Add log statements in service entry points.
- Propagate `-debug` flag from shim invokation to the service
- Load options when shim process is invoked to ensure runsc commands
  use the correct set of options, e.g. --debug --debug-logs=...
- Add debug options to the shim configuration directly, so it doesn't
  rely on containerd configuration (and restart) to enable shim debug.
- Save shim logs to dedicated file, so it's easier to read logs. They
  would be mixed with containerd logs and hard to distinguish
  otherwise.

PiperOrigin-RevId: 342179868

1 files changed, 13 insertions, 2 deletions

diff --git a/pkg/shim/runsc/utils.go b/pkg/shim/runsc/utils.go
index c514b3bc7..55f17d29e 100644
--- a/pkg/shim/runsc/utils.go
+++ b/pkg/shim/runsc/utils.go
@@ -36,9 +36,20 @@ func putBuf(b *bytes.Buffer) {
 	bytesBufferPool.Put(b)
 }
 
-// FormatLogPath parses runsc config, and fill in %ID% in the log path.
-func FormatLogPath(id string, config map[string]string) {
+// FormatRunscLogPath parses runsc config, and fill in %ID% in the log path.
+func FormatRunscLogPath(id string, config map[string]string) {
 	if path, ok := config["debug-log"]; ok {
 		config["debug-log"] = strings.Replace(path, "%ID%", id, -1)
 	}
 }
+
+// FormatShimLogPath creates the file path to the log file. It replaces %ID%
+// in the path with the provided "id". It also uses a default log name if the
+// path end with '/'.
+func FormatShimLogPath(path string, id string) string {
+	if strings.HasSuffix(path, "/") {
+		// Default format: <path>/runsc-shim-<ID>.log
+		path += "runsc-shim-%ID%.log"
+	}
+	return strings.Replace(path, "%ID%", id, -1)
+}