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#include <netlink/cli/utils.h>
#include <linux/taskstats.h>
#include <linux/genetlink.h>
static struct nla_policy attr_policy[TASKSTATS_TYPE_MAX+1] = {
[TASKSTATS_TYPE_PID] = { .type = NLA_U32 },
[TASKSTATS_TYPE_TGID] = { .type = NLA_U32 },
[TASKSTATS_TYPE_STATS] = { .minlen = sizeof(struct taskstats) },
[TASKSTATS_TYPE_AGGR_PID] = { .type = NLA_NESTED },
[TASKSTATS_TYPE_AGGR_TGID] = { .type = NLA_NESTED },
};
static int parse_cmd_new(struct nl_cache_ops *unused, struct genl_cmd *cmd,
struct genl_info *info, void *arg)
{
struct nlattr *attrs[TASKSTATS_TYPE_MAX+1];
struct nlattr *nested;
int err;
if (info->attrs[TASKSTATS_TYPE_AGGR_PID])
nested = info->attrs[TASKSTATS_TYPE_AGGR_PID];
else if (info->attrs[TASKSTATS_TYPE_AGGR_TGID])
nested = info->attrs[TASKSTATS_TYPE_AGGR_TGID];
else {
fprintf(stderr, "Invalid taskstats message: Unable to find "
"nested attribute/\n");
return NL_SKIP;
}
err = nla_parse_nested(attrs, TASKSTATS_TYPE_MAX, nested, attr_policy);
if (err < 0) {
nl_perror(err, "Error while parsing generic netlink message");
return err;
}
if (attrs[TASKSTATS_TYPE_STATS]) {
struct taskstats *stats = nla_data(attrs[TASKSTATS_TYPE_STATS]);
printf("%s pid %u uid %u gid %u parent %u\n",
stats->ac_comm, stats->ac_pid, stats->ac_uid,
stats->ac_gid, stats->ac_ppid);
}
return 0;
}
static int parse_cb(struct nl_msg *msg, void *arg)
{
return genl_handle_msg(msg, NULL);
}
static struct genl_cmd cmds[] = {
{
.c_id = TASKSTATS_CMD_NEW,
.c_name = "taskstats_new()",
.c_maxattr = TASKSTATS_TYPE_MAX,
.c_attr_policy = attr_policy,
.c_msg_parser = &parse_cmd_new,
},
};
#define ARRAY_SIZE(X) (sizeof(X) / sizeof((X)[0]))
static struct genl_ops ops = {
.o_name = TASKSTATS_GENL_NAME,
.o_cmds = cmds,
.o_ncmds = ARRAY_SIZE(cmds),
};
int main(int argc, char *argv[])
{
struct nl_sock *sock;
struct nl_msg *msg;
void *hdr;
int err;
sock = nl_cli_alloc_socket();
nl_cli_connect(sock, NETLINK_GENERIC);
if ((err = genl_register_family(&ops)) < 0)
nl_cli_fatal(err, "Unable to register Generic Netlink family");
if ((err = genl_ops_resolve(sock, &ops)) < 0)
nl_cli_fatal(err, "Unable to resolve family name");
if (genl_ctrl_resolve(sock, "nlctrl") != GENL_ID_CTRL)
nl_cli_fatal(NLE_INVAL, "Resolving of \"nlctrl\" failed");
msg = nlmsg_alloc();
if (msg == NULL)
nl_cli_fatal(NLE_NOMEM, "Unable to allocate netlink message");
hdr = genlmsg_put(msg, NL_AUTO_PORT, NL_AUTO_SEQ, ops.o_id,
0, 0, TASKSTATS_CMD_GET, TASKSTATS_GENL_VERSION);
if (hdr == NULL)
nl_cli_fatal(ENOMEM, "Unable to write genl header");
if ((err = nla_put_u32(msg, TASKSTATS_CMD_ATTR_PID, 1)) < 0)
nl_cli_fatal(err, "Unable to add attribute: %s", nl_geterror(err));
if ((err = nl_send_auto(sock, msg)) < 0)
nl_cli_fatal(err, "Unable to send message: %s", nl_geterror(err));
nlmsg_free(msg);
if ((err = nl_socket_modify_cb(sock, NL_CB_VALID, NL_CB_CUSTOM,
parse_cb, NULL)) < 0)
nl_cli_fatal(err, "Unable to modify valid message callback");
if ((err = nl_recvmsgs_default(sock)) < 0)
nl_cli_fatal(err, "Unable to receive message: %s", nl_geterror(err));
nl_close(sock);
nl_socket_free(sock);
return 0;
}
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