| 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 <stdio.h> |
| 21 | #include <stdlib.h> |
| 22 | #include <string.h> |
| 23 | #include <urcu/list.h> |
| 24 | |
| 25 | #include "lttngerr.h" |
| 26 | #include "session.h" |
| 27 | |
| 28 | /* Variables */ |
| 29 | static unsigned int session_count; |
| 30 | |
| 31 | /* Static internal function */ |
| 32 | static void add_session_list(struct ltt_session *ls); |
| 33 | static void del_session_list(struct ltt_session *ls); |
| 34 | |
| 35 | /* Init global session list */ |
| 36 | struct ltt_session_list ltt_session_list = { |
| 37 | .head = CDS_LIST_HEAD_INIT(ltt_session_list.head), |
| 38 | }; |
| 39 | |
| 40 | /* |
| 41 | * get_session_list |
| 42 | * |
| 43 | * Return a pointer to the session list. |
| 44 | */ |
| 45 | struct ltt_session_list *get_session_list(void) |
| 46 | { |
| 47 | return <t_session_list; |
| 48 | } |
| 49 | |
| 50 | /* |
| 51 | * get_session_count |
| 52 | * |
| 53 | * Return session_count |
| 54 | */ |
| 55 | unsigned int get_session_count(void) |
| 56 | { |
| 57 | return session_count; |
| 58 | } |
| 59 | |
| 60 | /* |
| 61 | * add_session_list |
| 62 | * |
| 63 | * Add a ltt_session structure to the global list. |
| 64 | */ |
| 65 | static void add_session_list(struct ltt_session *ls) |
| 66 | { |
| 67 | cds_list_add(&ls->list, <t_session_list.head); |
| 68 | session_count++; |
| 69 | } |
| 70 | |
| 71 | /* |
| 72 | * del_session_list |
| 73 | * |
| 74 | * Delete a ltt_session structure to the global list. |
| 75 | */ |
| 76 | static void del_session_list(struct ltt_session *ls) |
| 77 | { |
| 78 | cds_list_del(&ls->list); |
| 79 | /* Sanity check */ |
| 80 | if (session_count != 0) { |
| 81 | session_count--; |
| 82 | } |
| 83 | } |
| 84 | |
| 85 | /* |
| 86 | * find_session_by_uuid |
| 87 | * |
| 88 | * Return a ltt_session structure ptr that matches the uuid. |
| 89 | */ |
| 90 | struct ltt_session *find_session_by_uuid(uuid_t session_id) |
| 91 | { |
| 92 | int found = 0; |
| 93 | struct ltt_session *iter; |
| 94 | |
| 95 | /* Sanity check for NULL session_id */ |
| 96 | if (uuid_is_null(session_id)) { |
| 97 | goto end; |
| 98 | } |
| 99 | |
| 100 | cds_list_for_each_entry(iter, <t_session_list.head, list) { |
| 101 | if (uuid_compare(iter->uuid, session_id) == 0) { |
| 102 | found = 1; |
| 103 | break; |
| 104 | } |
| 105 | } |
| 106 | |
| 107 | end: |
| 108 | if (!found) { |
| 109 | iter = NULL; |
| 110 | } |
| 111 | return iter; |
| 112 | } |
| 113 | |
| 114 | /* |
| 115 | * find_session_by_name |
| 116 | * |
| 117 | * Return a ltt_session structure ptr that matches name. |
| 118 | * If no session found, NULL is returned. |
| 119 | */ |
| 120 | struct ltt_session *find_session_by_name(char *name) |
| 121 | { |
| 122 | int found = 0; |
| 123 | struct ltt_session *iter; |
| 124 | |
| 125 | cds_list_for_each_entry(iter, <t_session_list.head, list) { |
| 126 | if (strncmp(iter->name, name, strlen(name)) == 0) { |
| 127 | found = 1; |
| 128 | break; |
| 129 | } |
| 130 | } |
| 131 | |
| 132 | if (!found) { |
| 133 | iter = NULL; |
| 134 | } |
| 135 | |
| 136 | return iter; |
| 137 | } |
| 138 | |
| 139 | /* |
| 140 | * destroy_session |
| 141 | * |
| 142 | * Delete session from the global session list |
| 143 | * and free the memory. |
| 144 | * |
| 145 | * Return -1 if no session is found. |
| 146 | * On success, return 1; |
| 147 | */ |
| 148 | int destroy_session(uuid_t *uuid) |
| 149 | { |
| 150 | int found = -1; |
| 151 | struct ltt_session *iter; |
| 152 | |
| 153 | cds_list_for_each_entry(iter, <t_session_list.head, list) { |
| 154 | if (uuid_compare(iter->uuid, *uuid) == 0) { |
| 155 | DBG("Destroying session %s", iter->name); |
| 156 | del_session_list(iter); |
| 157 | free(iter); |
| 158 | found = 1; |
| 159 | break; |
| 160 | } |
| 161 | } |
| 162 | |
| 163 | return found; |
| 164 | } |
| 165 | |
| 166 | /* |
| 167 | * create_session |
| 168 | * |
| 169 | * Create a brand new session and add it to the |
| 170 | * global session list. |
| 171 | */ |
| 172 | int create_session(char *name, uuid_t *session_id) |
| 173 | { |
| 174 | struct ltt_session *new_session; |
| 175 | |
| 176 | DBG("Creating session %s", name); |
| 177 | |
| 178 | new_session = find_session_by_name(name); |
| 179 | if (new_session != NULL) { |
| 180 | goto error; |
| 181 | } |
| 182 | |
| 183 | /* Allocate session data structure */ |
| 184 | new_session = malloc(sizeof(struct ltt_session)); |
| 185 | if (new_session == NULL) { |
| 186 | perror("malloc"); |
| 187 | goto error_mem; |
| 188 | } |
| 189 | |
| 190 | if (name != NULL) { |
| 191 | if (asprintf(&new_session->name, "%s", name) < 0) { |
| 192 | goto error_mem; |
| 193 | } |
| 194 | } else { |
| 195 | /* Generate session name based on the session count */ |
| 196 | if (asprintf(&new_session->name, "%s%d", "lttng-", session_count) < 0) { |
| 197 | goto error_mem; |
| 198 | } |
| 199 | } |
| 200 | |
| 201 | /* UUID generation */ |
| 202 | uuid_generate(new_session->uuid); |
| 203 | uuid_copy(*session_id, new_session->uuid); |
| 204 | |
| 205 | /* |
| 206 | * Set consumer (identifier) to 0. This means that there is |
| 207 | * NO consumer attach to that session yet. |
| 208 | */ |
| 209 | new_session->ust_consumer = 0; |
| 210 | |
| 211 | /* Init kernel session */ |
| 212 | new_session->kernel_session = NULL; |
| 213 | new_session->kern_session_count = 0; |
| 214 | |
| 215 | /* Init list */ |
| 216 | CDS_INIT_LIST_HEAD(&new_session->ust_traces); |
| 217 | |
| 218 | /* Set trace list counter */ |
| 219 | new_session->ust_trace_count = 0; |
| 220 | |
| 221 | /* Add new session to the global session list */ |
| 222 | add_session_list(new_session); |
| 223 | |
| 224 | return 0; |
| 225 | |
| 226 | error: |
| 227 | return -1; |
| 228 | |
| 229 | error_mem: |
| 230 | return -ENOMEM; |
| 231 | } |
| 232 | |
| 233 | /* |
| 234 | * get_lttng_session |
| 235 | * |
| 236 | * Iterate over the global session list and |
| 237 | * fill the lttng_session array. |
| 238 | */ |
| 239 | void get_lttng_session(struct lttng_session *sessions) |
| 240 | { |
| 241 | int i = 0; |
| 242 | struct ltt_session *iter; |
| 243 | struct lttng_session lsess; |
| 244 | |
| 245 | DBG("Getting all available session"); |
| 246 | |
| 247 | /* Iterate over session list and append data after |
| 248 | * the control struct in the buffer. |
| 249 | */ |
| 250 | cds_list_for_each_entry(iter, <t_session_list.head, list) { |
| 251 | /* Copy name and uuid */ |
| 252 | uuid_copy(lsess.uuid, iter->uuid); |
| 253 | strncpy(lsess.name, iter->name, sizeof(lsess.name)); |
| 254 | lsess.name[sizeof(lsess.name) - 1] = '\0'; |
| 255 | memcpy(&sessions[i], &lsess, sizeof(lsess)); |
| 256 | i++; |
| 257 | /* Reset struct for next pass */ |
| 258 | memset(&lsess, 0, sizeof(lsess)); |
| 259 | } |
| 260 | } |
| 261 | |