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dd392e94 | 1 | /* |
21cf9b6b | 2 | * Copyright (C) 2011 EfficiOS Inc. |
dd392e94 FD |
3 | * Copyright (C) 2014 Mathieu Desnoyers <mathieu.desnoyers@efficios.com> |
4 | * Copyright (C) 2020 Francis Deslauriers <francis.deslauriers@efficios.com> | |
5 | * | |
c922647d | 6 | * SPDX-License-Identifier: LGPL-2.1-only |
dd392e94 FD |
7 | * |
8 | */ | |
9 | ||
dd392e94 FD |
10 | #include <stdbool.h> |
11 | #include <sys/stat.h> | |
12 | #include <sys/types.h> | |
13 | #include <unistd.h> | |
dd392e94 FD |
14 | |
15 | #include <lttng/constant.h> | |
16 | ||
c9e313bc SM |
17 | #include <common/compat/errno.hpp> |
18 | #include "error.hpp" | |
19 | #include "macros.hpp" | |
20 | #include "spawn-viewer.hpp" | |
dd392e94 FD |
21 | |
22 | ||
23 | static const char *babeltrace_bin = CONFIG_BABELTRACE_BIN; | |
24 | static const char *babeltrace2_bin = CONFIG_BABELTRACE2_BIN; | |
25 | ||
26 | /* | |
27 | * This is needed for each viewer since we are using execvp(). | |
28 | */ | |
29 | static const char *babeltrace_opts[] = { "babeltrace" }; | |
30 | static const char *babeltrace2_opts[] = { "babeltrace2" }; | |
31 | ||
32 | /* | |
33 | * Type is also use as the index in the viewers array. So please, make sure | |
34 | * your enum value is in the right order in the array below. | |
35 | */ | |
36 | enum viewer_type { | |
37 | VIEWER_BABELTRACE = 0, | |
38 | VIEWER_BABELTRACE2 = 1, | |
39 | VIEWER_USER_DEFINED = 2, | |
40 | }; | |
41 | ||
42 | static const struct viewer { | |
43 | const char *exec_name; | |
44 | enum viewer_type type; | |
45 | } viewers[] = { | |
46 | { "babeltrace", VIEWER_BABELTRACE }, | |
47 | { "babeltrace2", VIEWER_BABELTRACE2 }, | |
48 | { NULL, VIEWER_USER_DEFINED }, | |
49 | }; | |
50 | ||
51 | static const struct viewer *parse_viewer_option(const char *opt_viewer) | |
52 | { | |
53 | if (opt_viewer == NULL) { | |
54 | /* Default is babeltrace2 */ | |
55 | return &(viewers[VIEWER_BABELTRACE2]); | |
56 | } | |
57 | ||
58 | return &(viewers[VIEWER_USER_DEFINED]); | |
59 | } | |
60 | ||
61 | /* | |
62 | * Alloc an array of string pointer from a simple string having all options | |
63 | * seperated by spaces. Also adds the trace path to the arguments. | |
64 | * | |
65 | * The returning pointer is ready to be passed to execvp(). | |
66 | */ | |
67 | static char **alloc_argv_from_user_opts(char *opts, const char *trace_path) | |
68 | { | |
69 | int i = 0, ignore_space = 0; | |
70 | unsigned int num_opts = 1; | |
a825ed8c | 71 | char **argv, *token = opts, *saveptr = NULL; |
dd392e94 FD |
72 | |
73 | /* Count number of arguments. */ | |
74 | do { | |
75 | if (*token == ' ') { | |
76 | /* Use to ignore consecutive spaces */ | |
77 | if (!ignore_space) { | |
78 | num_opts++; | |
79 | } | |
80 | ignore_space = 1; | |
81 | } else { | |
82 | ignore_space = 0; | |
83 | } | |
84 | token++; | |
85 | } while (*token != '\0'); | |
86 | ||
87 | /* Add two here for the NULL terminating element and trace path */ | |
64803277 | 88 | argv = calloc<char *>(num_opts + 2); |
dd392e94 FD |
89 | if (argv == NULL) { |
90 | goto error; | |
91 | } | |
92 | ||
77368158 | 93 | token = strtok_r(opts, " ", &saveptr); |
dd392e94 FD |
94 | while (token != NULL) { |
95 | argv[i] = strdup(token); | |
96 | if (argv[i] == NULL) { | |
97 | goto error; | |
98 | } | |
77368158 | 99 | token = strtok_r(NULL, " ", &saveptr); |
dd392e94 FD |
100 | i++; |
101 | } | |
102 | ||
103 | argv[num_opts] = (char *) trace_path; | |
104 | argv[num_opts + 1] = NULL; | |
105 | ||
106 | return argv; | |
107 | ||
108 | error: | |
109 | if (argv) { | |
110 | for (i = 0; i < num_opts + 2; i++) { | |
111 | free(argv[i]); | |
112 | } | |
113 | free(argv); | |
114 | } | |
115 | ||
116 | return NULL; | |
117 | } | |
118 | ||
119 | /* | |
120 | * Alloc an array of string pointer from an array of strings. It also adds | |
121 | * the trace path to the argv. | |
122 | * | |
123 | * The returning pointer is ready to be passed to execvp(). | |
124 | */ | |
125 | static char **alloc_argv_from_local_opts(const char **opts, size_t opts_len, | |
126 | const char *trace_path, bool opt_live_mode) | |
127 | { | |
128 | char **argv; | |
64803277 | 129 | size_t mem_len; |
dd392e94 FD |
130 | |
131 | /* Add one for the NULL terminating element. */ | |
132 | mem_len = opts_len + 1; | |
133 | if (opt_live_mode) { | |
134 | /* Add 3 option for the live mode being "-i lttng-live URL". */ | |
135 | mem_len += 3; | |
136 | } else { | |
137 | /* Add option for the trace path. */ | |
138 | mem_len += 1; | |
139 | } | |
140 | ||
64803277 | 141 | argv = calloc<char *>(mem_len); |
dd392e94 FD |
142 | if (argv == NULL) { |
143 | goto error; | |
144 | } | |
145 | ||
146 | memcpy(argv, opts, sizeof(char *) * opts_len); | |
147 | ||
148 | if (opt_live_mode) { | |
149 | argv[opts_len] = (char *) "-i"; | |
150 | argv[opts_len + 1] = (char *) "lttng-live"; | |
151 | argv[opts_len + 2] = (char *) trace_path; | |
152 | argv[opts_len + 3] = NULL; | |
153 | } else { | |
154 | argv[opts_len] = (char *) trace_path; | |
155 | argv[opts_len + 1] = NULL; | |
156 | } | |
157 | ||
158 | error: | |
159 | return argv; | |
160 | } | |
161 | ||
162 | ||
163 | /* | |
164 | * Spawn viewer with the trace directory path. | |
165 | */ | |
166 | int spawn_viewer(const char *trace_path, char *opt_viewer, bool opt_live_mode) | |
167 | { | |
168 | int ret = 0; | |
169 | struct stat status; | |
170 | const char *viewer_bin = NULL; | |
171 | const struct viewer *viewer; | |
172 | char **argv = NULL; | |
173 | ||
174 | /* Check for --viewer option. */ | |
175 | viewer = parse_viewer_option(opt_viewer); | |
176 | if (viewer == NULL) { | |
177 | ret = -1; | |
178 | goto error; | |
179 | } | |
180 | ||
181 | retry_viewer: | |
182 | switch (viewer->type) { | |
183 | case VIEWER_BABELTRACE2: | |
184 | if (stat(babeltrace2_bin, &status) == 0) { | |
185 | viewer_bin = babeltrace2_bin; | |
186 | } else { | |
187 | viewer_bin = viewer->exec_name; | |
188 | } | |
189 | argv = alloc_argv_from_local_opts(babeltrace2_opts, | |
190 | ARRAY_SIZE(babeltrace2_opts), trace_path, | |
191 | opt_live_mode); | |
192 | break; | |
193 | case VIEWER_BABELTRACE: | |
194 | if (stat(babeltrace_bin, &status) == 0) { | |
195 | viewer_bin = babeltrace_bin; | |
196 | } else { | |
197 | viewer_bin = viewer->exec_name; | |
198 | } | |
199 | argv = alloc_argv_from_local_opts(babeltrace_opts, | |
200 | ARRAY_SIZE(babeltrace_opts), trace_path, | |
201 | opt_live_mode); | |
202 | break; | |
203 | case VIEWER_USER_DEFINED: | |
204 | argv = alloc_argv_from_user_opts(opt_viewer, trace_path); | |
205 | if (argv) { | |
206 | viewer_bin = argv[0]; | |
207 | } | |
208 | break; | |
209 | default: | |
210 | abort(); | |
211 | } | |
212 | ||
213 | if (argv == NULL || !viewer_bin) { | |
214 | ret = -1; | |
215 | goto error; | |
216 | } | |
217 | ||
218 | DBG("Using %s viewer", viewer_bin); | |
219 | ||
220 | ret = execvp(viewer_bin, argv); | |
221 | if (ret) { | |
222 | if (errno == ENOENT && viewer->exec_name) { | |
223 | if (viewer->type == VIEWER_BABELTRACE2) { | |
224 | /* Fallback to legacy babeltrace. */ | |
225 | DBG("Default viewer \"%s\" not installed on the system, falling back to \"%s\"", | |
226 | viewers[VIEWER_BABELTRACE2].exec_name, | |
227 | viewers[VIEWER_BABELTRACE].exec_name); | |
228 | viewer = &viewers[VIEWER_BABELTRACE]; | |
229 | free(argv); | |
230 | argv = NULL; | |
231 | goto retry_viewer; | |
232 | } else { | |
233 | ERR("Default viewer \"%s\" (and fallback \"%s\") not found on the system", | |
234 | viewers[VIEWER_BABELTRACE2].exec_name, | |
235 | viewers[VIEWER_BABELTRACE].exec_name); | |
236 | } | |
237 | } else { | |
238 | PERROR("Failed to launch \"%s\" viewer", viewer_bin); | |
239 | } | |
240 | ret = -1; | |
241 | goto error; | |
242 | } | |
243 | ||
244 | /* | |
245 | * This function should never return if successfull because `execvp(3)` | |
246 | * onle returns if an error has occurred. | |
247 | */ | |
a0377dfe | 248 | LTTNG_ASSERT(ret != 0); |
dd392e94 FD |
249 | error: |
250 | free(argv); | |
251 | return ret; | |
252 | } |