[Sheepdog] [PATCH 15/18] shepherd: support getting epoch information

[MORITA Kazutaka]

`shepherd info -t epoch` shows all the local epoch information at the target
node.

Signed-off-by: MORITA Kazutaka <morita.kazutaka at lab.ntt.co.jp>
---
 shepherd/shepherd.c |  102 ++++++++++++++++++++++++++++++++++++++++++++++++++-
 1 files changed, 101 insertions(+), 1 deletions(-)

diff --git a/shepherd/shepherd.c b/shepherd/shepherd.c
index 53c9b44..77c1c00 100644
--- a/shepherd/shepherd.c
+++ b/shepherd/shepherd.c
@@ -59,6 +59,7 @@ enum info_type {
 	INFO_OBJ,
 	INFO_VM,
 	INFO_CLUSTER,
+	INFO_EPOCH,
 	INFO_NONE,
 };
 
@@ -79,7 +80,7 @@ static void usage(int status)
 \n\
 Command syntax:\n\
   mkfs [--copies=N]\n\
-  info -t (vdi|dog|sheep|obj|cluster) [-f (list|tree|graph)] [-H (on|off)] [-R (on|off)] [-i N] [-e N] [vdiname]\n\
+  info -t (vdi|dog|sheep|obj|cluster|epoch) [-f (list|tree|graph)] [-H (on|off)] [-R (on|off)] [-i N] [-e N] [vdiname]\n\
   debug -o node_version\n\
   shutdown\n\
 \n\
@@ -1088,6 +1089,103 @@ rerun:
 		}
 		break;
 	}
+	case INFO_EPOCH:
+	{
+		int fd;
+		struct sd_epoch_req hdr;
+		struct sd_epoch_rsp *rsp = (struct sd_epoch_rsp *)&hdr;
+		unsigned rlen, wlen;
+		int i, j, n;
+		uint32_t *epoch_list;
+		struct sheepdog_node_list_entry pre_entries[SD_MAX_NODES];
+		struct sheepdog_node_list_entry entries[SD_MAX_NODES];
+		int pre_size, size;
+		char added_node[128], removed_node[128];
+		time_t ti;
+		struct tm tm;
+		char time[128];
+
+		fd = connect_to("localhost", sdport);
+		if (fd < 0)
+			break;
+
+		memset(&hdr, 0, sizeof(hdr));
+
+		hdr.opcode = SD_OP_GET_EPOCH_LIST;
+		hdr.epoch = node_list_version;
+		hdr.data_length = SD_DATA_OBJ_SIZE;
+		epoch_list = zalloc(hdr.data_length);
+		if (!epoch_list)
+			return 1;
+
+		rlen = hdr.data_length;
+		wlen = 0;
+		ret = exec_req(fd, (struct sd_req *)&hdr, epoch_list, &wlen, &rlen);
+
+		if (ret != 0)
+			break;
+
+		if (rsp->result != SD_RES_SUCCESS) {
+			fprintf(stderr, "failed to get epoch list, %x\n", rsp->result);
+			break;
+		}
+
+		n = rlen / sizeof(uint32_t);
+
+		printf("  Ctime              Epoch Id               Nodes\n");
+		pre_size = 0;
+
+		memset(&hdr, 0, sizeof(hdr));
+		hdr.opcode = SD_OP_READ_EPOCH;
+		hdr.epoch = node_list_version;
+		for (i = 0; i < n; i++) {
+			hdr.data_length = sizeof(entries);
+			hdr.request_epoch = epoch_list[i];
+			rlen = hdr.data_length;
+
+			ret = exec_req(fd, (struct sd_req *)&hdr, entries, &wlen, &rlen);
+
+			if (ret != 0)
+				break;
+
+			if (rsp->result != SD_RES_SUCCESS) {
+				fprintf(stderr, "failed to read epoch, %x\n", rsp->result);
+				break;
+			}
+
+			size = rlen;
+			if (size <= 0) {
+				pre_size = 0;
+				continue;
+			}
+			size /= sizeof(*entries);
+			added_node[0] = '\0';
+			removed_node[0] = '\0';
+			if (pre_size == 0 && epoch_list[i] != 1)
+				printf("       *\n");
+
+			ti = rsp->ctime >> 32;
+			localtime_r(&ti, &tm);
+			strftime(time, sizeof(time), "%y-%m-%d %H:%M:%S", &tm);
+
+			printf("%c %s %6d %016" PRIx64,
+			       rsp->is_updated ? 'U' : ' ', time, epoch_list[i],
+			       rsp->hval);
+			printf(" [");
+			for (j = 0; j < size; j++) {
+				printf("%s%s",
+				       (j == 0) ? "" : ", ",
+				       addr_to_str(added_node, sizeof(added_node),
+						   entries[j].addr, entries[j].port));
+			}
+			printf("]\n");
+			pre_size = size;
+			memcpy(pre_entries, entries, size);
+		}
+
+		close(fd);
+		break;
+	}
 	default:
 		ret = -1;
 		break;
@@ -1173,6 +1271,8 @@ int main(int argc, char **argv)
 				type = INFO_VM;
 			else if (!strcasecmp(optarg, "cluster"))
 				type = INFO_CLUSTER;
+			else if (!strcasecmp(optarg, "epoch"))
+				type = INFO_EPOCH;
 			else
 				usage(1);
 			break;
-- 
1.5.6.5