Commit | Line | Data |
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2691221a MD |
1 | /* |
2 | * lttng-ust-comm.c | |
3 | * | |
4 | * Copyright (C) 2011 David Goulet <david.goulet@polymtl.ca> | |
5 | * Copyright (C) 2011 Mathieu Desnoyers <mathieu.desnoyers@efficios.com> | |
6 | * | |
7 | * This library is free software; you can redistribute it and/or | |
8 | * modify it under the terms of the GNU Lesser General Public | |
9 | * License as published by the Free Software Foundation; only | |
10 | * version 2.1 of the License. | |
11 | * | |
12 | * This library is distributed in the hope that it will be useful, | |
13 | * but WITHOUT ANY WARRANTY; without even the implied warranty of | |
14 | * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU | |
15 | * Lesser General Public License for more details. | |
16 | * | |
17 | * You should have received a copy of the GNU Lesser General Public | |
18 | * License along with this library; if not, write to the Free Software | |
19 | * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA | |
20 | */ | |
21 | ||
22 | #include <sys/types.h> | |
23 | #include <sys/socket.h> | |
24 | #include <unistd.h> | |
25 | #include <errno.h> | |
b35d179d MD |
26 | #include <ust/lttng-ust-abi.h> |
27 | #include <lttng-ust-comm.h> | |
2691221a | 28 | #include <ust/usterr-signal-safe.h> |
d9e99d10 | 29 | #include <pthread.h> |
2691221a MD |
30 | |
31 | /* Socket from app (connect) to session daemon (listen) for communication */ | |
2691221a | 32 | static char global_apps_sock_path[PATH_MAX] = DEFAULT_GLOBAL_APPS_UNIX_SOCK; |
d9e99d10 | 33 | static pthread_t global_ust_listener; |
2691221a MD |
34 | |
35 | /* TODO: allow global_apps_sock_path override */ | |
36 | ||
2691221a | 37 | static char local_apps_sock_path[PATH_MAX]; |
d9e99d10 | 38 | static pthread_t local_ust_listener; |
2691221a MD |
39 | |
40 | static | |
9eb62b9c | 41 | int setup_local_apps_socket(void) |
2691221a MD |
42 | { |
43 | const char *home_dir; | |
2691221a MD |
44 | |
45 | home_dir = (const char *) getenv("HOME"); | |
46 | if (!home_dir) | |
47 | return -ENOENT; | |
48 | snprintf(local_apps_sock_path, PATH_MAX, | |
49 | DEFAULT_HOME_APPS_UNIX_SOCK, home_dir); | |
2691221a MD |
50 | return 0; |
51 | } | |
52 | ||
53 | static | |
54 | int register_app_to_sessiond(int socket) | |
55 | { | |
56 | ssize_t ret; | |
57 | struct { | |
e44418f3 MD |
58 | uint32_t major; |
59 | uint32_t minor; | |
2691221a MD |
60 | pid_t pid; |
61 | uid_t uid; | |
62 | } reg_msg; | |
63 | ||
e44418f3 MD |
64 | reg_msg.major = LTTNG_UST_COMM_VERSION_MAJOR; |
65 | reg_msg.minor = LTTNG_UST_COMM_VERSION_MINOR; | |
2691221a MD |
66 | reg_msg.pid = getpid(); |
67 | reg_msg.uid = getuid(); | |
68 | ||
69 | ret = lttcomm_send_unix_sock(socket, ®_msg, sizeof(reg_msg)); | |
70 | if (ret >= 0 && ret != sizeof(reg_msg)) | |
71 | return -EIO; | |
72 | return ret; | |
73 | } | |
74 | ||
d9e99d10 MD |
75 | |
76 | static | |
e7723462 | 77 | int handle_message(int sock, struct lttcomm_ust_msg *lum) |
d9e99d10 | 78 | { |
9eb62b9c MD |
79 | ssize_t len; |
80 | int ret; | |
81 | ||
e7723462 | 82 | switch (lum->cmd_type) { |
b35d179d | 83 | case UST_CREATE_SESSION: |
9eb62b9c | 84 | { |
e7723462 | 85 | struct lttcomm_ust_reply lur; |
d9e99d10 | 86 | |
9eb62b9c MD |
87 | DBG("Handling create session message"); |
88 | memset(&lur, 0, sizeof(lur)); | |
b35d179d | 89 | lur.cmd_type = UST_CREATE_SESSION; |
9eb62b9c MD |
90 | |
91 | /* ... */ | |
92 | ret = 0; | |
93 | ||
94 | if (!ret) | |
95 | lur.ret_code = LTTCOMM_OK; | |
96 | else | |
97 | lur.ret_code = LTTCOMM_SESSION_FAIL; | |
1ece9766 | 98 | lur.ret_val = 42; |
9eb62b9c MD |
99 | len = lttcomm_send_unix_sock(sock, &lur, sizeof(lur)); |
100 | switch (len) { | |
101 | case sizeof(lur): | |
102 | printf("message successfully sent\n"); | |
103 | break; | |
104 | case -1: | |
105 | if (errno == ECONNRESET) { | |
106 | printf("remote end closed connection\n"); | |
107 | return 0; | |
108 | } | |
109 | return -1; | |
110 | default: | |
111 | printf("incorrect message size: %zd\n", len); | |
112 | return -1; | |
113 | } | |
d9e99d10 | 114 | break; |
9eb62b9c | 115 | } |
d9e99d10 | 116 | default: |
e7723462 | 117 | ERR("Unimplemented command %d", (int) lum->cmd_type); |
d9e99d10 MD |
118 | return -1; |
119 | } | |
120 | return 0; | |
121 | } | |
122 | ||
123 | static | |
124 | void *ust_listener_thread(void *arg) | |
125 | { | |
9eb62b9c MD |
126 | const char *sock_path = (const char *) arg; |
127 | int sock; | |
d9e99d10 MD |
128 | int ret; |
129 | ||
9eb62b9c MD |
130 | /* Restart trying to connect to the session daemon */ |
131 | restart: | |
132 | ||
133 | /* Check for sessiond availability with pipe TODO */ | |
134 | ||
135 | /* Register */ | |
136 | ret = lttcomm_connect_unix_sock(sock_path); | |
137 | if (ret < 0) { | |
138 | ERR("Error connecting to global apps socket"); | |
139 | } | |
140 | sock = ret; | |
141 | ret = register_app_to_sessiond(sock); | |
142 | if (ret < 0) { | |
143 | ERR("Error registering app to local apps socket"); | |
144 | sleep(5); | |
145 | goto restart; | |
146 | } | |
d9e99d10 MD |
147 | for (;;) { |
148 | ssize_t len; | |
e7723462 | 149 | struct lttcomm_ust_msg lum; |
d9e99d10 MD |
150 | |
151 | /* Receive session handle */ | |
e7723462 | 152 | len = lttcomm_recv_unix_sock(sock, &lum, sizeof(lum)); |
d9e99d10 MD |
153 | switch (len) { |
154 | case 0: /* orderly shutdown */ | |
155 | DBG("ltt-sessiond has performed an orderly shutdown\n"); | |
156 | goto end; | |
e7723462 | 157 | case sizeof(lum): |
d9e99d10 | 158 | DBG("message received\n"); |
e7723462 | 159 | ret = handle_message(sock, &lum); |
d9e99d10 | 160 | if (ret) { |
9eb62b9c | 161 | ERR("Error handling message\n"); |
d9e99d10 MD |
162 | } |
163 | continue; | |
164 | case -1: | |
165 | if (errno == ECONNRESET) { | |
166 | ERR("remote end closed connection\n"); | |
167 | goto end; | |
168 | } | |
169 | goto end; | |
170 | default: | |
171 | ERR("incorrect message size: %zd\n", len); | |
172 | continue; | |
173 | } | |
174 | ||
175 | } | |
176 | end: | |
9eb62b9c MD |
177 | ret = close(sock); |
178 | if (ret) { | |
179 | ERR("Error closing local apps socket"); | |
180 | } | |
181 | goto restart; /* try to reconnect */ | |
d9e99d10 MD |
182 | return NULL; |
183 | } | |
184 | ||
185 | ||
2691221a MD |
186 | /* |
187 | * sessiond monitoring thread: monitor presence of global and per-user | |
188 | * sessiond by polling the application common named pipe. | |
189 | */ | |
190 | /* TODO */ | |
191 | ||
192 | void __attribute__((constructor)) lttng_ust_comm_init(void) | |
193 | { | |
194 | int ret; | |
195 | ||
196 | init_usterr(); | |
197 | ||
2691221a | 198 | /* Connect to the per-user (local) sessiond apps socket */ |
9eb62b9c | 199 | ret = setup_local_apps_socket(); |
2691221a | 200 | if (ret) { |
9eb62b9c | 201 | ERR("Error setting up to local apps socket"); |
2691221a | 202 | } |
9eb62b9c MD |
203 | #if 0 |
204 | ret = pthread_create(&global_ust_listener, NULL, | |
205 | ust_listener_thread, global_apps_sock_path); | |
206 | #endif //0 | |
207 | ret = pthread_create(&local_ust_listener, NULL, | |
208 | ust_listener_thread, local_apps_sock_path); | |
2691221a MD |
209 | } |
210 | ||
211 | void __attribute__((destructor)) lttng_ust_comm_exit(void) | |
212 | { | |
213 | int ret; | |
214 | ||
9eb62b9c MD |
215 | /* |
216 | * Using pthread_cancel here because: | |
217 | * A) we don't want to hang application teardown. | |
218 | * B) the thread is not allocating any resource. | |
219 | */ | |
220 | ret = pthread_cancel(global_ust_listener); | |
221 | if (ret) { | |
222 | ERR("Error cancelling global ust listener thread"); | |
2691221a | 223 | } |
9eb62b9c MD |
224 | ret = pthread_cancel(local_ust_listener); |
225 | if (ret) { | |
226 | ERR("Error cancelling local ust listener thread"); | |
2691221a | 227 | } |
b35d179d | 228 | lttng_ust_abi_exit(); |
2691221a | 229 | } |