Add ust start trace feature
[lttng-tools.git] / liblttsessiondcomm / liblttsessiondcomm.c
1 /*
2 * Copyright (C) 2011 - David Goulet <david.goulet@polymtl.ca>
3 *
4 * This program is free software; you can redistribute it and/or
5 * modify it under the terms of the GNU General Public License
6 * as published by the Free Software Foundation; either version 2
7 * of the License, or (at your option) any later version.
8 *
9 * This program is distributed in the hope that it will be useful,
10 * but WITHOUT ANY WARRANTY; without even the implied warranty of
11 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
12 * GNU General Public License for more details.
13 *
14 * You should have received a copy of the GNU General Public License
15 * along with this program; if not, write to the Free Software
16 * Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
17 */
18
19 #define _GNU_SOURCE
20 #include <limits.h>
21 #include <stdio.h>
22 #include <stdlib.h>
23 #include <string.h>
24 #include <sys/socket.h>
25 #include <sys/stat.h>
26 #include <sys/types.h>
27 #include <sys/un.h>
28 #include <unistd.h>
29
30 #include "liblttsessiondcomm.h"
31
32 /*
33 * Human readable error message.
34 */
35 static const char *lttcomm_readable_code[] = {
36 [ LTTCOMM_ERR_INDEX(LTTCOMM_OK) ] = "Success",
37 [ LTTCOMM_ERR_INDEX(LTTCOMM_ERR) ] = "Unknown error",
38 [ LTTCOMM_ERR_INDEX(LTTCOMM_UND) ] = "Undefined command",
39 [ LTTCOMM_ERR_INDEX(LTTCOMM_NO_SESSION) ] = "No session found",
40 [ LTTCOMM_ERR_INDEX(LTTCOMM_LIST_FAIL) ] = "Unable to list traceable apps",
41 [ LTTCOMM_ERR_INDEX(LTTCOMM_NO_APPS) ] = "No traceable apps found",
42 [ LTTCOMM_ERR_INDEX(LTTCOMM_NO_SESS) ] = "No session found",
43 [ LTTCOMM_ERR_INDEX(LTTCOMM_NO_TRACE) ] = "No trace found",
44 [ LTTCOMM_ERR_INDEX(LTTCOMM_FATAL) ] = "Fatal error of the session daemon",
45 [ LTTCOMM_ERR_INDEX(LTTCOMM_CREATE_FAIL) ] = "Create trace failed",
46 [ LTTCOMM_ERR_INDEX(LTTCOMM_START_FAIL) ] = "Start trace failed",
47 [ LTTCOMM_ERR_INDEX(LTTCOMM_NO_TRACEABLE) ] = "App is not traceable",
48 [ LTTCOMM_ERR_INDEX(LTTCOMM_SELECT_SESS) ] = "A session MUST be selected",
49 [ LTTCOMM_ERR_INDEX(LTTCOMM_EXIST_SESS) ] = "Session name already exist",
50 };
51
52 /*
53 * lttcom_get_readable_code
54 *
55 * Return ptr to string representing a human readable
56 * error code from the lttcomm_return_code enum.
57 *
58 * These code MUST be negative in other to treat that
59 * as an error value.
60 */
61 const char *lttcomm_get_readable_code(enum lttcomm_return_code code)
62 {
63 int tmp_code = -code;
64
65 if (tmp_code >= LTTCOMM_OK && tmp_code < LTTCOMM_NR) {
66 return lttcomm_readable_code[LTTCOMM_ERR_INDEX(tmp_code)];
67 }
68
69 return "Unknown error code";
70 }
71
72 /*
73 * lttcomm_connect_unix_sock
74 *
75 * Connect to unix socket using the path name.
76 */
77 int lttcomm_connect_unix_sock(const char *pathname)
78 {
79 struct sockaddr_un sun;
80 int fd;
81 int ret = 1;
82
83 fd = socket(PF_UNIX, SOCK_STREAM, 0);
84 if (fd < 0) {
85 perror("socket");
86 goto error;
87 }
88
89 memset(&sun, 0, sizeof(sun));
90 sun.sun_family = AF_UNIX;
91 strncpy(sun.sun_path, pathname, sizeof(sun.sun_path));
92
93 ret = connect(fd, (struct sockaddr *) &sun, sizeof(sun));
94 if (ret < 0) {
95 perror("connect");
96 goto error;
97 }
98
99 return fd;
100
101 error:
102 return -1;
103 }
104
105 /*
106 * lttcomm_accept_unix_sock
107 *
108 * Do an accept(2) on the sock and return the
109 * new file descriptor. The socket MUST be bind(2) before.
110 */
111 int lttcomm_accept_unix_sock(int sock)
112 {
113 int new_fd;
114 struct sockaddr_un sun;
115 socklen_t len = 0;
116
117 /* Blocking call */
118 new_fd = accept(sock, (struct sockaddr *) &sun, &len);
119 if (new_fd < 0) {
120 perror("accept");
121 goto error;
122 }
123
124 return new_fd;
125
126 error:
127 return -1;
128 }
129
130 /*
131 * lttcomm_create_unix_sock
132 *
133 * Creates a AF_UNIX local socket using pathname
134 * bind the socket upon creation and return the fd.
135 */
136 int lttcomm_create_unix_sock(const char *pathname)
137 {
138 struct sockaddr_un sun;
139 int fd;
140 int ret = -1;
141
142 /* Create server socket */
143 if ((fd = socket(PF_UNIX, SOCK_STREAM, 0)) < 0) {
144 perror("socket");
145 goto error;
146 }
147
148 memset(&sun, 0, sizeof(sun));
149 sun.sun_family = AF_UNIX;
150 strncpy(sun.sun_path, pathname, strlen(pathname));
151
152 ret = bind(fd, (struct sockaddr *) &sun, sizeof(sun));
153 if (ret < 0) {
154 perror("bind");
155 goto error;
156 }
157
158 return fd;
159
160 error:
161 return ret;
162 }
163
164 /*
165 * lttcomm_listen_unix_sock
166 *
167 * Make the socket listen using MAX_LISTEN.
168 */
169 int lttcomm_listen_unix_sock(int sock)
170 {
171 int ret;
172
173 ret = listen(sock, MAX_LISTEN);
174 if (ret < 0) {
175 perror("listen");
176 }
177
178 return ret;
179 }
180
181 /*
182 * lttcomm_recv_unix_sock
183 *
184 * Receive data of size len in put that data into
185 * the buf param. Using recvmsg API.
186 * Return the size of received data.
187 */
188 ssize_t lttcomm_recv_unix_sock(int sock, void *buf, size_t len)
189 {
190 struct msghdr msg;
191 struct iovec iov[1];
192 ssize_t ret = -1;
193
194 memset(&msg, 0, sizeof(msg));
195
196 iov[0].iov_base = buf;
197 iov[0].iov_len = len;
198 msg.msg_iov = iov;
199 msg.msg_iovlen = 1;
200
201 ret = recvmsg(sock, &msg, 0);
202 if (ret < 0) {
203 perror("recvmsg");
204 }
205
206 return ret;
207 }
208
209 /*
210 * lttcomm_send_unix_sock
211 *
212 * Send buf data of size len. Using sendmsg API.
213 * Return the size of sent data.
214 */
215 ssize_t lttcomm_send_unix_sock(int sock, void *buf, size_t len)
216 {
217 struct msghdr msg;
218 struct iovec iov[1];
219 ssize_t ret = -1;
220
221 memset(&msg, 0, sizeof(msg));
222
223 iov[0].iov_base = buf;
224 iov[0].iov_len = len;
225 msg.msg_iov = iov;
226 msg.msg_iovlen = 1;
227
228 ret = sendmsg(sock, &msg, 0);
229 if (ret < 0) {
230 perror("sendmsg");
231 }
232
233 return ret;
234 }
235
236 /*
237 * lttcomm_close_unix_sock
238 *
239 * Shutdown cleanly a unix socket.
240 */
241 int lttcomm_close_unix_sock(int sock)
242 {
243 int ret;
244
245 /* Shutdown receptions and transmissions */
246 ret = shutdown(sock, SHUT_RDWR);
247 if (ret < 0) {
248 perror("shutdown");
249 }
250
251 return ret;
252 }
This page took 0.034758 seconds and 5 git commands to generate.