Mi set-session command: support and validation
[lttng-tools.git] / src / bin / lttng / commands / set_session.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 modify
5 * it under the terms of the GNU General Public License, version 2 only,
6 * as published by the Free Software Foundation.
7 *
8 * This program is distributed in the hope that it will be useful,
9 * but WITHOUT ANY WARRANTY; without even the implied warranty of
10 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
11 * GNU General Public License for more details.
12 *
13 * You should have received a copy of the GNU General Public License along
14 * with this program; if not, write to the Free Software Foundation, Inc.,
15 * 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
16 */
17
18 #define _GNU_SOURCE
19 #include <popt.h>
20 #include <stdio.h>
21 #include <stdlib.h>
22 #include <string.h>
23 #include <sys/stat.h>
24 #include <sys/types.h>
25 #include <unistd.h>
26 #include <assert.h>
27
28 #include <common/mi-lttng.h>
29
30 #include "../command.h"
31
32 static char *opt_session_name;
33
34 enum {
35 OPT_HELP = 1,
36 OPT_LIST_OPTIONS,
37 };
38
39 static struct mi_writer *writer;
40
41 static struct poptOption long_options[] = {
42 /* longName, shortName, argInfo, argPtr, value, descrip, argDesc */
43 {"help", 'h', POPT_ARG_NONE, 0, OPT_HELP, 0, 0},
44 {"list-options", 0, POPT_ARG_NONE, NULL, OPT_LIST_OPTIONS, NULL, NULL},
45 {0, 0, 0, 0, 0, 0, 0}
46 };
47
48 /*
49 * usage
50 */
51 static void usage(FILE *ofp)
52 {
53 fprintf(ofp, "usage: lttng set-session NAME [OPTIONS]\n");
54 fprintf(ofp, "\n");
55 fprintf(ofp, "Options:\n");
56 fprintf(ofp, " -h, --help Show this help\n");
57 fprintf(ofp, " --list-options Simple listing of options\n");
58 fprintf(ofp, "\n");
59 }
60
61 /*
62 * Print the necessary mi for a session and name.
63 */
64 static int mi_print(char *session_name)
65 {
66 int ret;
67
68 assert(writer);
69 assert(session_name);
70
71 /*
72 * Open a sessions element
73 * This is purely for validation purpose
74 */
75 ret = mi_lttng_sessions_open(writer);
76 if (ret) {
77 goto end;
78 }
79
80 /* Open a session element */
81 ret = mi_lttng_writer_open_element(writer, config_element_session);
82 if (ret) {
83 goto end;
84 }
85
86 /* Session name */
87 ret = mi_lttng_writer_write_element_string(writer , config_element_name,
88 session_name);
89 if (ret) {
90 goto end;
91 }
92
93 /* Close session and sessions element */
94 ret = mi_lttng_close_multi_element(writer, 2);
95 if (ret) {
96 goto end;
97 }
98 end:
99 return ret;
100 }
101
102 /*
103 * set_session
104 */
105 static int set_session(void)
106 {
107 int ret = CMD_SUCCESS;
108
109 if (opt_session_name && strlen(opt_session_name) > NAME_MAX) {
110 ERR("Session name too long. Length must be lower or equal to %d",
111 NAME_MAX);
112 ret = CMD_ERROR;
113 goto error;
114 }
115
116 ret = config_init(opt_session_name);
117 if (ret < 0) {
118 ERR("Unable to set session name");
119 ret = CMD_ERROR;
120 goto error;
121 }
122
123 MSG("Session set to %s", opt_session_name);
124 if (lttng_opt_mi) {
125 ret = mi_print(opt_session_name);
126 if (ret) {
127 ret = CMD_ERROR;
128 goto error;
129 }
130 }
131
132 ret = CMD_SUCCESS;
133
134 error:
135 return ret;
136 }
137
138 /*
139 * cmd_set_session
140 */
141 int cmd_set_session(int argc, const char **argv)
142 {
143 int opt, ret = CMD_SUCCESS, command_ret = CMD_SUCCESS, success = 1;
144 static poptContext pc;
145
146 pc = poptGetContext(NULL, argc, argv, long_options, 0);
147 poptReadDefaultConfig(pc, 0);
148
149 while ((opt = poptGetNextOpt(pc)) != -1) {
150 switch (opt) {
151 case OPT_HELP:
152 usage(stdout);
153 goto end;
154 case OPT_LIST_OPTIONS:
155 list_cmd_options(stdout, long_options);
156 goto end;
157 default:
158 usage(stderr);
159 ret = CMD_UNDEFINED;
160 goto end;
161 }
162 }
163
164 opt_session_name = (char *) poptGetArg(pc);
165 if (opt_session_name == NULL) {
166 ERR("Missing session name");
167 usage(stderr);
168 ret = CMD_ERROR;
169 goto end;
170 }
171
172 /* Mi check */
173 if (lttng_opt_mi) {
174 writer = mi_lttng_writer_create(fileno(stdout), lttng_opt_mi);
175 if (!writer) {
176 ret = -LTTNG_ERR_NOMEM;
177 goto end;
178 }
179
180 /* Open command element */
181 ret = mi_lttng_writer_command_open(writer,
182 mi_lttng_element_command_set_session);
183 if (ret) {
184 ret = CMD_ERROR;
185 goto end;
186 }
187
188 /* Open output element */
189 ret = mi_lttng_writer_open_element(writer,
190 mi_lttng_element_command_output);
191 if (ret) {
192 ret = CMD_ERROR;
193 goto end;
194 }
195 }
196
197 command_ret = set_session();
198 if (command_ret) {
199 success = 0;
200 }
201
202 /* Mi closing */
203 if (lttng_opt_mi) {
204 /* Close output element */
205 ret = mi_lttng_writer_close_element(writer);
206 if (ret) {
207 ret = CMD_ERROR;
208 goto end;
209 }
210
211 /* Success ? */
212 ret = mi_lttng_writer_write_element_bool(writer,
213 mi_lttng_element_command_success, success);
214 if (ret) {
215 ret = CMD_ERROR;
216 goto end;
217 }
218
219 /* Command element close */
220 ret = mi_lttng_writer_command_close(writer);
221 if (ret) {
222 ret = CMD_ERROR;
223 goto end;
224 }
225 }
226
227 end:
228 /* Mi clean-up */
229 if (writer && mi_lttng_writer_destroy(writer)) {
230 /* Preserve original error code */
231 ret = ret ? ret : LTTNG_ERR_MI_IO_FAIL;
232 }
233
234 /* Overwrite ret if an error occured during set_session() */
235 ret = command_ret ? command_ret : ret;
236
237 poptFreeContext(pc);
238 return ret;
239 }
This page took 0.051795 seconds and 4 git commands to generate.