glusterd: add a cli command to trigger a statedump on a client

With this, we will be able to trigger statedumps on remote Gluster
clients, mainly targetted for applications using libgfapi.

Design:
SIGUSR signal is the most comman way of taking a statedump in Gluster.
But it cannot be used for libgfapi based processes, as the process
loading the library might have already consumed SIGUSR signal. Hence
going by the command way.

One has to issue a Gluster command to initiate a statedump on the
libgfapi based client. The command takes hostname and PID as an
argument. All the glusterds in the cluster, check if they are connected
to the specified hostname, and send an RPC request to all the connected
clients from that hostname (via the mgmt connection).

> URL: http://review.gluster.org/16357
> BUG: 1169302
> Signed-off-by: Poornima G <pgurusid@redhat.com>
> [ndevos: minor fixes and split patch in smaller pieces]
> Reviewed-on-master: https://review.gluster.org/9228
> Reviewed-by: Niels de Vos <ndevos@redhat.com>
> Tested-by: Niels de Vos <ndevos@redhat.com>
> Reviewed-by: Kaleb KEITHLEY <kkeithle@redhat.com>
> Reviewed-by: Samikshan Bairagya <samikshan@gmail.com>

BUG: 1418981
Change-Id: Icbe4d2f026b32a2c7d5535e1bfb2cdaaff042e91
Signed-off-by: Shyam <srangana@redhat.com>
Reviewed-on: https://review.gluster.org/16601
Smoke: Gluster Build System <jenkins@build.gluster.org>
Reviewed-by: Niels de Vos <ndevos@redhat.com>
NetBSD-regression: NetBSD Build System <jenkins@build.gluster.org>
CentOS-regression: Gluster Build System <jenkins@build.gluster.org>

2 files changed, 38 insertions, 12 deletions

diff --git a/cli/src/cli-cmd-parser.c b/cli/src/cli-cmd-parser.c
index 9b1f1db88e8..d234ad09c4e 100644
--- a/cli/src/cli-cmd-parser.c
+++ b/cli/src/cli-cmd-parser.c
@@ -3541,19 +3541,44 @@ cli_cmd_volume_statedump_options_parse (const char **words, int wordcount,
         dict_t  *dict = NULL;
         int     option_cnt = 0;
         char    *option = NULL;
-        char    option_str[100] = {0,};
-
-        for (i = 3; i < wordcount; i++, option_cnt++) {
-                if (!cli_cmd_validate_dumpoption (words[i], &option)) {
+        char    option_str[_POSIX_HOST_NAME_MAX + 100] = {0,};
+        char    *tmp = NULL;
+        char    *ip_addr = NULL;
+        char    *pid = NULL;
+
+        if ((wordcount >= 5) && ((strcmp (words[3], "client")) == 0)) {
+                tmp = gf_strdup(words[4]);
+                if (!tmp) {
+                        ret = -1;
+                        goto out;
+                }
+                ip_addr = strtok(tmp, ":");
+                pid = strtok(NULL, ":");
+                if (valid_internet_address (ip_addr, _gf_true)
+                   && pid && gf_valid_pid (pid, strlen(pid))) {
+                        strncat (option_str, words[3], strlen (words[3]));
+                        strncat (option_str, " ", 1);
+                        strncat (option_str, ip_addr, strlen (ip_addr));
+                        strncat (option_str, " ", 1);
+                        strncat (option_str, pid, strlen (pid));
+                        option_cnt = 3;
+                } else {
+                        ret = -1;
+                        goto out;
+                }
+        } else {
+                for (i = 3; i < wordcount; i++, option_cnt++) {
+                        if (!cli_cmd_validate_dumpoption (words[i], &option)) {
+                                ret = -1;
+                                goto out;
+                        }
+                        strncat (option_str, option, strlen (option));
+                        strncat (option_str, " ", 1);
+                }
+                if ((strstr (option_str, "nfs")) && strstr (option_str, "quotad")) {
                         ret = -1;
                         goto out;
                 }
-                strncat (option_str, option, strlen (option));
-                strncat (option_str, " ", 1);
-        }
-        if((strstr (option_str, "nfs")) && strstr (option_str, "quotad")) {
-                ret = -1;
-                goto out;
         }
 
         dict = dict_new ();
@@ -3570,6 +3595,7 @@ cli_cmd_volume_statedump_options_parse (const char **words, int wordcount,
 
         *options = dict;
 out:
+        GF_FREE (tmp);
         if (ret && dict)
                 dict_unref (dict);
         if (ret)
diff --git a/cli/src/cli-cmd-volume.c b/cli/src/cli-cmd-volume.c
index dbf1e3e2326..5f07a057d47 100644
--- a/cli/src/cli-cmd-volume.c
+++ b/cli/src/cli-cmd-volume.c
@@ -3285,8 +3285,8 @@ struct cli_cmd volume_cmds[] = {
           cli_cmd_volume_heal_cbk,
           "self-heal commands on volume specified by <VOLNAME>"},
 
-        {"volume statedump <VOLNAME> [nfs|quotad] [all|mem|iobuf|callpool|priv|fd|"
-         "inode|history]...",
+        {"volume statedump <VOLNAME> [[nfs|quotad] [all|mem|iobuf|callpool|"
+         "priv|fd|inode|history]... | [client <hostname:process-id>]]",
          cli_cmd_volume_statedump_cbk,
          "perform statedump on bricks"},