| 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; only version 2 |
| 7 | * of the License. |
| 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 <errno.h> |
| 21 | #include <pthread.h> |
| 22 | #include <stdio.h> |
| 23 | #include <stdlib.h> |
| 24 | #include <string.h> |
| 25 | #include <unistd.h> |
| 26 | |
| 27 | #include <lttngerr.h> |
| 28 | |
| 29 | #include "ust-app.h" |
| 30 | |
| 31 | #include "benchmark.h" |
| 32 | |
| 33 | /* Init ust traceable application's list */ |
| 34 | static struct ust_app_list ust_app_list = { |
| 35 | .head = CDS_LIST_HEAD_INIT(ust_app_list.head), |
| 36 | .lock = PTHREAD_MUTEX_INITIALIZER, |
| 37 | .count = 0, |
| 38 | }; |
| 39 | |
| 40 | /* |
| 41 | * Add a traceable application structure to the global list. |
| 42 | */ |
| 43 | static void add_app_to_list(struct ust_app *lta) |
| 44 | { |
| 45 | cds_list_add(<a->list, &ust_app_list.head); |
| 46 | ust_app_list.count++; |
| 47 | } |
| 48 | |
| 49 | /* |
| 50 | * Delete a traceable application structure from the global list. |
| 51 | */ |
| 52 | static void del_app_from_list(struct ust_app *lta) |
| 53 | { |
| 54 | struct ltt_ust_channel *chan; |
| 55 | |
| 56 | cds_list_del(<a->list); |
| 57 | /* Sanity check */ |
| 58 | if (ust_app_list.count > 0) { |
| 59 | ust_app_list.count--; |
| 60 | } |
| 61 | |
| 62 | cds_list_for_each_entry(chan, <a->channels.head, list) { |
| 63 | trace_ust_destroy_channel(chan); |
| 64 | } |
| 65 | } |
| 66 | |
| 67 | /* |
| 68 | * Iterate over the traceable apps list and return a pointer or NULL if not |
| 69 | * found. |
| 70 | */ |
| 71 | static struct ust_app *find_app_by_sock(int sock) |
| 72 | { |
| 73 | struct ust_app *iter; |
| 74 | |
| 75 | cds_list_for_each_entry(iter, &ust_app_list.head, list) { |
| 76 | if (iter->sock == sock) { |
| 77 | /* Found */ |
| 78 | return iter; |
| 79 | } |
| 80 | } |
| 81 | |
| 82 | return NULL; |
| 83 | } |
| 84 | |
| 85 | /* |
| 86 | * Return pointer to traceable apps list. |
| 87 | */ |
| 88 | struct ust_app_list *ust_app_get_list(void) |
| 89 | { |
| 90 | return &ust_app_list; |
| 91 | } |
| 92 | |
| 93 | /* |
| 94 | * Acquire traceable apps list lock. |
| 95 | */ |
| 96 | void ust_app_lock_list(void) |
| 97 | { |
| 98 | pthread_mutex_lock(&ust_app_list.lock); |
| 99 | } |
| 100 | |
| 101 | /* |
| 102 | * Release traceable apps list lock. |
| 103 | */ |
| 104 | void ust_app_unlock_list(void) |
| 105 | { |
| 106 | pthread_mutex_unlock(&ust_app_list.lock); |
| 107 | } |
| 108 | |
| 109 | /* |
| 110 | * Iterate over the traceable apps list and return a pointer or NULL if not |
| 111 | * found. |
| 112 | */ |
| 113 | struct ust_app *ust_app_get_by_pid(pid_t pid) |
| 114 | { |
| 115 | struct ust_app *iter; |
| 116 | |
| 117 | cds_list_for_each_entry(iter, &ust_app_list.head, list) { |
| 118 | if (iter->pid == pid) { |
| 119 | /* Found */ |
| 120 | DBG2("Found traceable app by pid %d", pid); |
| 121 | return iter; |
| 122 | } |
| 123 | } |
| 124 | |
| 125 | DBG2("Traceable app with pid %d not found", pid); |
| 126 | |
| 127 | return NULL; |
| 128 | } |
| 129 | |
| 130 | /* |
| 131 | * Using pid and uid (of the app), allocate a new ust_app struct and |
| 132 | * add it to the global traceable app list. |
| 133 | * |
| 134 | * On success, return 0, else return malloc ENOMEM. |
| 135 | */ |
| 136 | int ust_app_register(struct ust_register_msg *msg, int sock) |
| 137 | { |
| 138 | struct ust_app *lta; |
| 139 | |
| 140 | lta = malloc(sizeof(struct ust_app)); |
| 141 | if (lta == NULL) { |
| 142 | perror("malloc"); |
| 143 | return -ENOMEM; |
| 144 | } |
| 145 | |
| 146 | lta->uid = msg->uid; |
| 147 | lta->gid = msg->gid; |
| 148 | lta->pid = msg->pid; |
| 149 | lta->ppid = msg->ppid; |
| 150 | lta->v_major = msg->major; |
| 151 | lta->v_minor = msg->minor; |
| 152 | lta->sock = sock; |
| 153 | strncpy(lta->name, msg->name, sizeof(lta->name)); |
| 154 | lta->name[16] = '\0'; |
| 155 | CDS_INIT_LIST_HEAD(<a->channels.head); |
| 156 | |
| 157 | ust_app_lock_list(); |
| 158 | add_app_to_list(lta); |
| 159 | ust_app_unlock_list(); |
| 160 | |
| 161 | DBG("App registered with pid:%d ppid:%d uid:%d gid:%d sock:%d name:%s" |
| 162 | " (version %d.%d)", lta->pid, lta->ppid, lta->uid, lta->gid, |
| 163 | lta->sock, lta->name, lta->v_major, lta->v_minor); |
| 164 | |
| 165 | return 0; |
| 166 | } |
| 167 | |
| 168 | /* |
| 169 | * Unregister app by removing it from the global traceable app list and freeing |
| 170 | * the data struct. |
| 171 | * |
| 172 | * The socket is already closed at this point so no close to sock. |
| 173 | */ |
| 174 | void ust_app_unregister(int sock) |
| 175 | { |
| 176 | struct ust_app *lta; |
| 177 | |
| 178 | tracepoint(ust_unregister_start); |
| 179 | |
| 180 | ust_app_lock_list(); |
| 181 | lta = find_app_by_sock(sock); |
| 182 | if (lta) { |
| 183 | DBG("PID %d unregistered with sock %d", lta->pid, sock); |
| 184 | del_app_from_list(lta); |
| 185 | close(lta->sock); |
| 186 | free(lta); |
| 187 | } |
| 188 | ust_app_unlock_list(); |
| 189 | |
| 190 | tracepoint(ust_unregister_stop); |
| 191 | } |
| 192 | |
| 193 | /* |
| 194 | * Return traceable_app_count |
| 195 | */ |
| 196 | unsigned int ust_app_list_count(void) |
| 197 | { |
| 198 | unsigned int count; |
| 199 | |
| 200 | ust_app_lock_list(); |
| 201 | count = ust_app_list.count; |
| 202 | ust_app_unlock_list(); |
| 203 | |
| 204 | return count; |
| 205 | } |
| 206 | |
| 207 | /* |
| 208 | * Free and clean all traceable apps of the global list. |
| 209 | */ |
| 210 | void ust_app_clean_list(void) |
| 211 | { |
| 212 | struct ust_app *iter, *tmp; |
| 213 | |
| 214 | /* |
| 215 | * Don't acquire list lock here. This function should be called from |
| 216 | * cleanup() functions meaning that the program will exit. |
| 217 | */ |
| 218 | cds_list_for_each_entry_safe(iter, tmp, &ust_app_list.head, list) { |
| 219 | del_app_from_list(iter); |
| 220 | close(iter->sock); |
| 221 | free(iter); |
| 222 | } |
| 223 | } |