gsctool: print sensible date when listing flash log contents

Displaying epoch values in the flash log entries does not help the end
user to synchronize the flash log events with other logs generated on
the device.

This patch changes the log output format to display the device time
zone in the first line and then all present log entries with timestamp
in 'dd:mm:yy hh:mm:ss' format.

BUG=b:153764696
TEST=ran the new gsctool image on a Chrome OS device:

    $ gsctool -a -L
    Log time zone is PST
    Dec 31 69 16:00:01 : 00
    May 06 20 21:20:41 : 09 01
    ...
    May 08 20 12:09:21 : 09 00
    May 08 20 12:09:22 : 09 03
    May 08 20 12:09:23 : 09 06

Signed-off-by: Vadim Bendebury <vbendeb@chromium.org>
Change-Id: I3fca12e1679fbdd9e0e168606014e84c89c42402
Reviewed-on: https://chromium-review.googlesource.com/c/chromiumos/platform/ec/+/2191282
Reviewed-by: Namyoon Woo <namyoon@chromium.org>

1 files changed, 16 insertions, 1 deletions

diff --git a/extra/usb_updater/gsctool.c b/extra/usb_updater/gsctool.c
index 74c4a1b5fc..2f10998682 100644
--- a/extra/usb_updater/gsctool.c
+++ b/extra/usb_updater/gsctool.c
@@ -2463,11 +2463,15 @@ static int process_get_flog(struct transfer_descriptor *td, uint32_t prev_stamp)
 	int rv;
 	const int max_retries = 3;
 	int retries = max_retries;
+	bool time_zone_reported = false;
 
 	while (retries--) {
 		union entry_u entry;
 		size_t resp_size;
 		size_t i;
+		struct tm loc_time;
+		time_t entry_epoch;
+		char date_str[25];
 
 		resp_size = sizeof(entry);
 		rv = send_vendor_command(td, VENDOR_CC_POP_LOG_ENTRY,
@@ -2489,7 +2493,18 @@ static int process_get_flog(struct transfer_descriptor *td, uint32_t prev_stamp)
 			return 0;
 
 		memcpy(&prev_stamp, &entry.r.timestamp, sizeof(prev_stamp));
-		printf("%10u:%02x", prev_stamp, entry.r.type);
+		entry_epoch = prev_stamp;
+		localtime_r(&entry_epoch, &loc_time);
+
+		if (!time_zone_reported) {
+			strftime(date_str, sizeof(date_str), "%Z", &loc_time);
+			printf("Log time zone is %s\n", date_str);
+			time_zone_reported = true;
+		}
+
+		/* Date format is MMM DD YY HH:mm:ss */
+		strftime(date_str, sizeof(date_str), "%b %d %y %T", &loc_time);
+		printf("%s : %02x", date_str, entry.r.type);
 		for (i = 0; i < FLASH_LOG_PAYLOAD_SIZE(entry.r.size); i++)
 			printf(" %02x", entry.r.payload[i]);
 		printf("\n");