libustcmd/ustcmd.c

   1 /* Copyright (C) 2009  Pierre-Marc Fournier, Philippe Proulx-Barrette
   2  *
   3  * This library is free software; you can redistribute it and/or
   4  * modify it under the terms of the GNU Lesser General Public
   5  * License as published by the Free Software Foundation; either
   6  * version 2.1 of the License, or (at your option) any later version.
   7  *
   8  * This library 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 GNU
  11  * Lesser General Public License for more details.
  12  *
  13  * You should have received a copy of the GNU Lesser General Public
  14  * License along with this library; if not, write to the Free Software
  15  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301 USA
  16  */
  17
  18 #define _GNU_SOURCE
  19 #include <stdio.h>
  20 #include <unistd.h>
  21 #include <getopt.h>
  22 #include <stdlib.h>
  23 #include <fcntl.h>
  24 #include <string.h>
  25 #include <dirent.h>
  26
  27 #include "ustcomm.h"
  28 #include "ust/ustcmd.h"
  29 #include "usterr.h"
  30
  31 pid_t *ustcmd_get_online_pids(void)
  32 {
  33         struct dirent *dirent;
  34         DIR *dir;
  35         unsigned int ret_size = 1 * sizeof(pid_t), i = 0;
  36
  37         dir = opendir(SOCK_DIR);
  38         if (!dir) {
  39                 return NULL;
  40         }
  41
  42         pid_t *ret = (pid_t *) malloc(ret_size);
  43
  44         while ((dirent = readdir(dir))) {
  45                 if (!strcmp(dirent->d_name, ".") ||
  46                         !strcmp(dirent->d_name, "..")) {
  47
  48                         continue;
  49                 }
  50
  51                 if (dirent->d_type != DT_DIR &&
  52                         !!strcmp(dirent->d_name, "ustd")) {
  53
  54                         sscanf(dirent->d_name, "%u", (unsigned int *) &ret[i]);
  55                         if (pid_is_online(ret[i])) {
  56                                 ret_size += sizeof(pid_t);
  57                                 ret = (pid_t *) realloc(ret, ret_size);
  58                                 ++i;
  59                         }
  60                 }
  61         }
  62
  63         ret[i] = 0; /* Array end */
  64
  65         if (ret[0] == 0) {
  66                  /* No PID at all */
  67                 free(ret);
  68                 return NULL;
  69         }
  70
  71         closedir(dir);
  72         return ret;
  73 }
  74
  75 /**
  76  * Sets marker state (USTCMD_MS_ON or USTCMD_MS_OFF).
  77  *
  78  * @param mn    Marker name
  79  * @param state Marker's new state
  80  * @param pid   Traced process ID
  81  * @return      0 if successful, or errors {USTCMD_ERR_GEN, USTCMD_ERR_ARG}
  82  */
  83 int ustcmd_set_marker_state(const char *mn, int state, pid_t pid)
  84 {
  85         char *cmd_str [] = {"disable_marker", "enable_marker"};
  86         char *cmd;
  87         int result;
  88
  89         if (mn == NULL) {
  90                 return USTCMD_ERR_ARG;
  91         }
  92
  93         if (asprintf(&cmd, "%s %s", cmd_str[state], mn) < 0) {
  94                 ERR("ustcmd_set_marker_state : asprintf failed (%s %s)",
  95                     cmd_str[state], mn);
  96                 return USTCMD_ERR_GEN;
  97         }
  98
  99         result = ustcmd_send_cmd(cmd, pid, NULL);
 100         if (result != 1) {
 101                 free(cmd);
 102                 return USTCMD_ERR_GEN;
 103         }
 104
 105         free(cmd);
 106         return 0;
 107 }
 108
 109 /**
 110  * Set subbuffer size.
 111  *
 112  * @param channel_size  Channel name and size
 113  * @param pid           Traced process ID
 114  * @return              0 if successful, or error
 115  */
 116 int ustcmd_set_subbuf_size(const char *channel_size, pid_t pid)
 117 {
 118         char *cmd;
 119         int result;
 120
 121         if (asprintf(&cmd, "%s %s", "set_subbuf_size", channel_size) < 0) {
 122                 ERR("ustcmd_set_subbuf_size : asprintf failed (set_subbuf_size %s)",
 123                     channel_size);
 124                 return -1;
 125         }
 126
 127         result = ustcmd_send_cmd(cmd, pid, NULL);
 128         if (result != 1) {
 129                 free(cmd);
 130                 return 1;
 131         }
 132
 133         free(cmd);
 134         return 0;
 135 }
 136
 137 /**
 138  * Set subbuffer num.
 139  *
 140  * @param channel_num   Channel name and num
 141  * @param pid           Traced process ID
 142  * @return              0 if successful, or error
 143  */
 144 int ustcmd_set_subbuf_num(const char *channel_size, pid_t pid)
 145 {
 146         char *cmd;
 147         int result;
 148
 149         if (asprintf(&cmd, "%s %s", "set_subbuf_num", channel_size) < 0) {
 150                 ERR("ustcmd_set_subbuf_num : asprintf failed (set_subbuf_num %s",
 151                     channel_size);
 152                 return -1;
 153         }
 154
 155         result = ustcmd_send_cmd(cmd, pid, NULL);
 156         if (result != 1) {
 157                 free(cmd);
 158                 return 1;
 159         }
 160
 161         free(cmd);
 162         return 0;
 163 }
 164
 165 /**
 166  * Get subbuffer size.
 167  *
 168  * @param channel       Channel name
 169  * @param pid           Traced process ID
 170  * @return              subbuf size if successful, or error
 171  */
 172 int ustcmd_get_subbuf_size(const char *channel, pid_t pid)
 173 {
 174         char *cmd, *reply;
 175         int result;
 176
 177         /* format: channel_cpu */
 178         if (asprintf(&cmd, "%s %s_0", "get_subbuf_size", channel) < 0) {
 179                 ERR("ustcmd_get_subbuf_size : asprintf failed (get_subbuf_size, %s_0",
 180                     channel);
 181                 return -1;
 182         }
 183
 184         result = ustcmd_send_cmd(cmd, pid, &reply);
 185         if (result != 1) {
 186                 free(cmd);
 187                 return -1;
 188         }
 189
 190         result = atoi(reply);
 191         free(cmd);
 192         free(reply);
 193         return result;
 194 }
 195
 196 /**
 197  * Get subbuffer num.
 198  *
 199  * @param channel       Channel name
 200  * @param pid           Traced process ID
 201  * @return              subbuf cnf if successful, or error
 202  */
 203 int ustcmd_get_subbuf_num(const char *channel, pid_t pid)
 204 {
 205         char *cmd, *reply;
 206         int result;
 207
 208         /* format: channel_cpu */
 209         if (asprintf(&cmd, "%s %s_0", "get_n_subbufs", channel) < 0) {
 210                 ERR("ustcmd_get_subbuf_num : asprintf failed (get_n_subbufs, %s_0",
 211                     channel);
 212                 return -1;
 213         }
 214
 215         result = ustcmd_send_cmd(cmd, pid, &reply);
 216         if (result != 1) {
 217                 free(cmd);
 218                 return -1;
 219         }
 220
 221         result = atoi(reply);
 222         free(cmd);
 223         free(reply);
 224         return result;
 225 }
 226
 227 /**
 228  * Destroys an UST trace according to a PID.
 229  *
 230  * @param pid   Traced process ID
 231  * @return      0 if successful, or error USTCMD_ERR_GEN
 232  */
 233 int ustcmd_destroy_trace(pid_t pid)
 234 {
 235         int result;
 236
 237         result = ustcmd_send_cmd("trace_destroy", pid, NULL);
 238         if (result != 1) {
 239                 return USTCMD_ERR_GEN;
 240         }
 241
 242         return 0;
 243 }
 244
 245 /**
 246  * Starts an UST trace (and setups it) according to a PID.
 247  *
 248  * @param pid   Traced process ID
 249  * @return      0 if successful, or error USTCMD_ERR_GEN
 250  */
 251 int ustcmd_setup_and_start(pid_t pid)
 252 {
 253         int result;
 254
 255         result = ustcmd_send_cmd("start", pid, NULL);
 256         if (result != 1) {
 257                 return USTCMD_ERR_GEN;
 258         }
 259
 260         return 0;
 261 }
 262
 263 /**
 264  * Creates an UST trace according to a PID.
 265  *
 266  * @param pid   Traced process ID
 267  * @return      0 if successful, or error USTCMD_ERR_GEN
 268  */
 269 int ustcmd_create_trace(pid_t pid)
 270 {
 271         int result;
 272
 273         result = ustcmd_send_cmd("trace_create", pid, NULL);
 274         if (result != 1) {
 275                 return USTCMD_ERR_GEN;
 276         }
 277
 278         return 0;
 279 }
 280
 281 /**
 282  * Starts an UST trace according to a PID.
 283  *
 284  * @param pid   Traced process ID
 285  * @return      0 if successful, or error USTCMD_ERR_GEN
 286  */
 287 int ustcmd_start_trace(pid_t pid)
 288 {
 289         int result;
 290
 291         result = ustcmd_send_cmd("trace_start", pid, NULL);
 292         if (result != 1) {
 293                 return USTCMD_ERR_GEN;
 294         }
 295
 296         return 0;
 297 }
 298
 299 /**
 300  * Alloc an UST trace according to a PID.
 301  *
 302  * @param pid   Traced process ID
 303  * @return      0 if successful, or error USTCMD_ERR_GEN
 304  */
 305 int ustcmd_alloc_trace(pid_t pid)
 306 {
 307         int result;
 308
 309         result = ustcmd_send_cmd("trace_alloc", pid, NULL);
 310         if (result != 1) {
 311                 return USTCMD_ERR_GEN;
 312         }
 313
 314         return 0;
 315 }
 316
 317 /**
 318  * Stops an UST trace according to a PID.
 319  *
 320  * @param pid   Traced process ID
 321  * @return      0 if successful, or error USTCMD_ERR_GEN
 322  */
 323 int ustcmd_stop_trace(pid_t pid)
 324 {
 325         int result;
 326
 327         result = ustcmd_send_cmd("trace_stop", pid, NULL);
 328         if (result != 1) {
 329                 return USTCMD_ERR_GEN;
 330         }
 331
 332         return 0;
 333 }
 334
 335 /**
 336  * Counts newlines ('\n') in a string.
 337  *
 338  * @param str   String to search in
 339  * @return      Total newlines count
 340  */
 341 unsigned int ustcmd_count_nl(const char *str)
 342 {
 343         unsigned int i = 0, tot = 0;
 344
 345         while (str[i] != '\0') {
 346                 if (str[i] == '\n') {
 347                         ++tot;
 348                 }
 349                 ++i;
 350         }
 351
 352         return tot;
 353 }
 354
 355 /**
 356  * Frees a CMSF array.
 357  *
 358  * @param cmsf  CMSF array to free
 359  * @return      0 if successful, or error USTCMD_ERR_ARG
 360  */
 361 int ustcmd_free_cmsf(struct marker_status *cmsf)
 362 {
 363         if (cmsf == NULL) {
 364                 return USTCMD_ERR_ARG;
 365         }
 366
 367         unsigned int i = 0;
 368         while (cmsf[i].channel != NULL) {
 369                 free(cmsf[i].channel);
 370                 free(cmsf[i].marker);
 371                 free(cmsf[i].fs);
 372                 ++i;
 373         }
 374         free(cmsf);
 375
 376         return 0;
 377 }
 378
 379 /**
 380  * Gets channel/marker/state/format string for a given PID.
 381  *
 382  * @param cmsf  Pointer to CMSF array to be filled (callee allocates, caller
 383  *              frees with `ustcmd_free_cmsf')
 384  * @param pid   Targeted PID
 385  * @return      0 if successful, or -1 on error
 386  */
 387 int ustcmd_get_cmsf(struct marker_status **cmsf, const pid_t pid)
 388 {
 389         char *big_str = NULL;
 390         int result;
 391         struct marker_status *tmp_cmsf = NULL;
 392         unsigned int i = 0, cmsf_ind = 0;
 393
 394         if (cmsf == NULL) {
 395                 return -1;
 396         }
 397         result = ustcmd_send_cmd("list_markers", pid, &big_str);
 398         if (result != 1) {
 399                 return -1;
 400         }
 401
 402         if (result != 1) {
 403                 ERR("error while getting markers list");
 404                 return -1;
 405         }
 406
 407         tmp_cmsf = (struct marker_status *) malloc(sizeof(struct marker_status) *
 408                 (ustcmd_count_nl(big_str) + 1));
 409         if (tmp_cmsf == NULL) {
 410                 return -1;
 411         }
 412
 413         /* Parse received reply string (format: "[chan]/[mark] [st] [fs]"): */
 414         while (big_str[i] != '\0') {
 415                 char state;
 416
 417                 sscanf(big_str + i, "marker: %a[^/]/%a[^ ] %c %a[^\n]",
 418                         &tmp_cmsf[cmsf_ind].channel,
 419                         &tmp_cmsf[cmsf_ind].marker,
 420                         &state,
 421                         &tmp_cmsf[cmsf_ind].fs);
 422                 tmp_cmsf[cmsf_ind].state = (state == USTCMD_MS_CHR_ON ?
 423                         USTCMD_MS_ON : USTCMD_MS_OFF); /* Marker state */
 424
 425                 while (big_str[i] != '\n') {
 426                         ++i; /* Go to next '\n' */
 427                 }
 428                 ++i; /* Skip current pointed '\n' */
 429                 ++cmsf_ind;
 430         }
 431         tmp_cmsf[cmsf_ind].channel = NULL;
 432         tmp_cmsf[cmsf_ind].marker = NULL;
 433         tmp_cmsf[cmsf_ind].fs = NULL;
 434
 435         *cmsf = tmp_cmsf;
 436
 437         free(big_str);
 438         return 0;
 439 }
 440
 441 /**
 442  * Set socket path
 443  *
 444  * @param sock_path     Socket path
 445  * @param pid           Traced process ID
 446  * @return              0 if successful, or error
 447  */
 448 int ustcmd_set_sock_path(const char *sock_path, pid_t pid)
 449 {
 450         char *cmd;
 451         int result;
 452
 453         if (asprintf(&cmd, "%s %s", "set_sock_path", sock_path) < 0) {
 454                 ERR("ustcmd_set_sock_path : asprintf failed (set_sock_path, %s",
 455                     sock_path);
 456                 return -1;
 457         }
 458
 459         result = ustcmd_send_cmd(cmd, pid, NULL);
 460         if (result != 1) {
 461                 free(cmd);
 462                 return USTCMD_ERR_GEN;
 463         }
 464
 465         free(cmd);
 466         return 0;
 467 }
 468
 469 /**
 470  * Get socket path
 471  *
 472  * @param sock_path     Pointer to where the socket path will be returned
 473  * @param pid           Traced process ID
 474  * @return              0 if successful, or error
 475  */
 476 int ustcmd_get_sock_path(char **sock_path, pid_t pid)
 477 {
 478         char *cmd, *reply;
 479         int result;
 480
 481         if (asprintf(&cmd, "%s", "get_sock_path") < 0) {
 482                 ERR("ustcmd_get_sock_path : asprintf failed");
 483                 return USTCMD_ERR_GEN;
 484         }
 485
 486         result = ustcmd_send_cmd(cmd, pid, &reply);
 487         if (result != 1) {
 488                 free(cmd);
 489                 return USTCMD_ERR_GEN;
 490         }
 491
 492         free(cmd);
 493         *sock_path = reply;
 494         return 0;
 495 }
 496
 497 int ustcmd_force_switch(pid_t pid)
 498 {
 499         int result;
 500
 501         result = ustcmd_send_cmd("force_switch", pid, NULL);
 502         if (result != 1) {
 503                 return USTCMD_ERR_GEN;
 504         }
 505
 506         return 0;
 507 }
 508
 509 /**
 510  * Sends a given command to a traceable process
 511  *
 512  * @param cmd   Null-terminated command to send
 513  * @param pid   Targeted PID
 514  * @param reply Pointer to string to be filled with a reply string (must
 515  *              be NULL if no reply is needed for the given command).
 516  * @return      -1 if not successful, 0 on EOT, 1 on success
 517  */
 518
 519 int ustcmd_send_cmd(const char *cmd, const pid_t pid, char **reply)
 520 {
 521         struct ustcomm_connection conn;
 522         int retval;
 523
 524         if (ustcomm_connect_app(pid, &conn)) {
 525                 ERR("could not connect to PID %u", (unsigned int) pid);
 526                 return -1;
 527         }
 528
 529         retval = ustcomm_send_request(&conn, cmd, reply);
 530
 531         ustcomm_close_app(&conn);
 532
 533         return retval;
 534 }