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 
ctdb_client_call_send(TALLOC_CTX * mem_ctx,struct tevent_context * ev,struct ctdb_client_context * client,struct ctdb_req_call * request)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 
ctdb_client_call_state_destructor(struct ctdb_client_call_state * state)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 
ctdb_client_call_done(struct tevent_req * subreq)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 
ctdb_client_reply_call(struct ctdb_client_context * client,uint8_t * buf,size_t buflen,uint32_t reqid)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 
ctdb_client_call_recv(struct tevent_req * req,TALLOC_CTX * mem_ctx,struct ctdb_reply_call ** reply,int * perr)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 }
185