ctdb/client/client_call.c

   1 /*
   2    CTDB client code
   3
   4    Copyright (C) Amitay Isaacs  2015
   5
   6    This program is free software; you can redistribute it and/or modify
   7    it under the terms of the GNU General Public License as published by
   8    the Free Software Foundation; either version 3 of the License, or
   9    (at your option) any later version.
  10
  11    This program is distributed in the hope that it will be useful,
  12    but WITHOUT ANY WARRANTY; without even the implied warranty of
  13    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  14    GNU General Public License for more details.
  15
  16    You should have received a copy of the GNU General Public License
  17    along with this program; if not, see <http://www.gnu.org/licenses/>.
  18 */
  19
  20 #include "replace.h"
  21 #include "system/network.h"
  22 #include "system/filesys.h"
  23
  24 #include <talloc.h>
  25 #include <tevent.h>
  26 #include <tdb.h>
  27
  28 #include "lib/util/tevent_unix.h"
  29
  30 #include "common/reqid.h"
  31 #include "common/srvid.h"
  32 #include "common/comm.h"
  33
  34 #include "protocol/protocol.h"
  35 #include "protocol/protocol_api.h"
  36
  37 #include "client/client_private.h"
  38 #include "client/client.h"
  39
  40
  41 /*
  42  * Handle REQ_CALL and REPLY_CALL
  43  */
  44
  45 struct ctdb_client_call_state {
  46         struct ctdb_client_context *client;
  47         uint32_t reqid;
  48         struct ctdb_reply_call *reply;
  49         struct tevent_req *req;
  50 };
  51
  52 static int ctdb_client_call_state_destructor(
  53         struct ctdb_client_call_state *state);
  54 static void ctdb_client_call_done(struct tevent_req *subreq);
  55
  56 struct tevent_req *ctdb_client_call_send(TALLOC_CTX *mem_ctx,
  57                                          struct tevent_context *ev,
  58                                          struct ctdb_client_context *client,
  59                                          struct ctdb_req_call *request)
  60 {
  61         struct ctdb_req_header h;
  62         struct tevent_req *req, *subreq;
  63         struct ctdb_client_call_state *state;
  64         uint32_t reqid;
  65         uint8_t *buf;
  66         size_t datalen, buflen;
  67         int ret;
  68
  69         req = tevent_req_create(mem_ctx, &state,
  70                                 struct ctdb_client_call_state);
  71         if (req == NULL) {
  72                 return NULL;
  73         }
  74
  75         reqid = reqid_new(client->idr, state);
  76         if (reqid == REQID_INVALID) {
  77                 talloc_free(req);
  78                 return NULL;
  79         }
  80
  81         state->client = client;
  82         state->reqid = reqid;
  83         state->req = req;
  84         state->reply = talloc_zero(state, struct ctdb_reply_call);
  85         if (tevent_req_nomem(state->reply, req)) {
  86                 return tevent_req_post(req, ev);
  87         }
  88
  89         talloc_set_destructor(state, ctdb_client_call_state_destructor);
  90
  91         ctdb_req_header_fill(&h, 0, CTDB_REQ_CALL, CTDB_CURRENT_NODE,
  92                              client->pnn, reqid);
  93
  94         datalen = ctdb_req_call_len(&h, request);
  95         ret = ctdb_allocate_pkt(state, datalen, &buf, &buflen);
  96         if (ret != 0) {
  97                 tevent_req_error(req, ret);
  98                 return tevent_req_post(req, ev);
  99         }
 100
 101         ret = ctdb_req_call_push(&h, request, buf, &buflen);
 102         if (ret != 0) {
 103                 tevent_req_error(req, ret);
 104                 return tevent_req_post(req, ev);
 105         }
 106
 107         subreq = comm_write_send(state, ev, client->comm, buf, buflen);
 108         if (tevent_req_nomem(subreq, req)) {
 109                 return tevent_req_post(req, ev);
 110         }
 111         tevent_req_set_callback(subreq, ctdb_client_call_done, req);
 112
 113         return req;
 114 }
 115
 116 static int ctdb_client_call_state_destructor(
 117         struct ctdb_client_call_state *state)
 118 {
 119         reqid_remove(state->client->idr, state->reqid);
 120         return 0;
 121 }
 122
 123 static void ctdb_client_call_done(struct tevent_req *subreq)
 124 {
 125         struct tevent_req *req = tevent_req_callback_data(
 126                 subreq, struct tevent_req);
 127         bool status;
 128         int ret;
 129
 130         status = comm_write_recv(subreq, &ret);
 131         TALLOC_FREE(subreq);
 132         if (! status) {
 133                 tevent_req_error(req, ret);
 134                 return;
 135         }
 136
 137         /* wait for the reply */
 138 }
 139
 140 void ctdb_client_reply_call(struct ctdb_client_context *client,
 141                             uint8_t *buf, size_t buflen, uint32_t reqid)
 142 {
 143         struct ctdb_req_header h;
 144         struct ctdb_client_call_state *state;
 145         int ret;
 146
 147         state = reqid_find(client->idr, reqid, struct ctdb_client_call_state);
 148         if (state == NULL) {
 149                 return;
 150         }
 151
 152         if (reqid != state->reqid) {
 153                 return;
 154         }
 155
 156         ret = ctdb_reply_call_pull(buf, buflen, &h, state, state->reply);
 157         if (ret != 0) {
 158                 tevent_req_error(state->req, ret);
 159                 return;
 160         }
 161
 162         tevent_req_done(state->req);
 163 }
 164
 165 bool ctdb_client_call_recv(struct tevent_req *req, TALLOC_CTX *mem_ctx,
 166                            struct ctdb_reply_call **reply, int *perr)
 167 {
 168         struct ctdb_client_call_state *state = tevent_req_data(
 169                 req, struct ctdb_client_call_state);
 170         int err;
 171
 172         if (tevent_req_is_unix_error(req, &err)) {
 173                 if (perr != NULL) {
 174                         *perr = err;
 175                 }
 176                 return false;
 177         }
 178
 179         if (reply != NULL) {
 180                 *reply = talloc_steal(mem_ctx, state->reply);
 181         }
 182
 183         return true;
 184 }