healthd: logd: add timestamp to kernel logged battery messages

Aid monotonic to realtime logging synchronization correction in
the Android ecosystem by providing a periodic notification.  We
now have the following messages in the kernel logs:

- PM: suspend entry %Y-%m-%d %H:%M:%S.%09q UTC
- PM: suspend exit %Y-%m-%d %H:%M:%S.%09q UTC
- Suspended for %s.%03q seconds
- healthd: battery l=100 ... %Y-%m-%d %H:%M:%S.%09q UTC

Alter klogd to resynchronize on healthd messages as well.

NB: Time using strftime format, %q is a reference to fractional
second as introduced into log_time strptime method.

Bug: 21868540
Change-Id: I854afc0a07dff9c7f26d2b2f68990e52bf90e300

1 files changed, 10 insertions, 0 deletions

diff --git a/logd/LogKlog.cpp b/logd/LogKlog.cpp
index eff26f5..1e6f55f 100644
--- a/logd/LogKlog.cpp
+++ b/logd/LogKlog.cpp
@@ -254,6 +254,7 @@ void LogKlog::sniffTime(log_time &now, const char **buf, bool reverse) {
     if ((cp = now.strptime(*buf, "[ %s.%q]"))) {
         static const char suspend[] = "PM: suspend entry ";
         static const char resume[] = "PM: suspend exit ";
+        static const char healthd[] = "healthd: battery ";
         static const char suspended[] = "Suspended for ";
 
         if (isspace(*cp)) {
@@ -263,6 +264,15 @@ void LogKlog::sniffTime(log_time &now, const char **buf, bool reverse) {
             calculateCorrection(now, cp + sizeof(suspend) - 1);
         } else if (!strncmp(cp, resume, sizeof(resume) - 1)) {
             calculateCorrection(now, cp + sizeof(resume) - 1);
+        } else if (!strncmp(cp, healthd, sizeof(healthd) - 1)) {
+            // look for " 2???-??-?? ??:??:??.????????? ???"
+            const char *tp;
+            for (tp = cp + sizeof(healthd) - 1; *tp && (*tp != '\n'); ++tp) {
+                if ((tp[0] == ' ') && (tp[1] == '2') && (tp[5] == '-')) {
+                    calculateCorrection(now, tp + 1);
+                    break;
+                }
+            }
         } else if (!strncmp(cp, suspended, sizeof(suspended) - 1)) {
             log_time real;
             char *endp;