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 "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         asprintf(&cmd, "%s %s", cmd_str[state], mn);
  94
  95         result = ustcmd_send_cmd(cmd, pid, NULL);
  96         if (result) {
  97                 free(cmd);
  98                 return USTCMD_ERR_GEN;
  99         }
 100
 101         free(cmd);
 102         return 0;
 103 }
 104
 105 /**
 106  * Set subbuffer size.
 107  *
 108  * @param channel_size  Channel name and size
 109  * @param pid           Traced process ID
 110  * @return              0 if successful, or error
 111  */
 112 int ustcmd_set_subbuf_size(const char *channel_size, pid_t pid)
 113 {
 114         char *cmd;
 115         int result;
 116
 117         asprintf(&cmd, "%s %s", "set_subbuf_size", channel_size);
 118
 119         result = ustcmd_send_cmd(cmd, pid, NULL);
 120         if (result != 1) {
 121                 free(cmd);
 122                 return 1;
 123         }
 124
 125         free(cmd);
 126         return 0;
 127 }
 128
 129 /**
 130  * Set subbuffer num.
 131  *
 132  * @param channel_num   Channel name and num
 133  * @param pid           Traced process ID
 134  * @return              0 if successful, or error
 135  */
 136 int ustcmd_set_subbuf_num(const char *channel_size, pid_t pid)
 137 {
 138         char *cmd;
 139         int result;
 140
 141         asprintf(&cmd, "%s %s", "set_subbuf_num", channel_size);
 142
 143         result = ustcmd_send_cmd(cmd, pid, NULL);
 144         if (result != 1) {
 145                 free(cmd);
 146                 return 1;
 147         }
 148
 149         free(cmd);
 150         return 0;
 151 }
 152
 153 /**
 154  * Get subbuffer size.
 155  *
 156  * @param channel       Channel name
 157  * @param pid           Traced process ID
 158  * @return              subbuf size if successful, or error
 159  */
 160 int ustcmd_get_subbuf_size(const char *channel, pid_t pid)
 161 {
 162         char *cmd, *reply;
 163         int result;
 164
 165         /* format: channel_cpu */
 166         asprintf(&cmd, "%s %s_0", "get_subbuf_size", channel);
 167
 168         result = ustcmd_send_cmd(cmd, pid, &reply);
 169         if (result) {
 170                 free(cmd);
 171                 free(reply);
 172                 return -1;
 173         }
 174
 175         result = atoi(reply);
 176         free(cmd);
 177         free(reply);
 178         return result;
 179 }
 180
 181 /**
 182  * Get subbuffer num.
 183  *
 184  * @param channel       Channel name
 185  * @param pid           Traced process ID
 186  * @return              subbuf cnf if successful, or error
 187  */
 188 int ustcmd_get_subbuf_num(const char *channel, pid_t pid)
 189 {
 190         char *cmd, *reply;
 191         int result;
 192
 193         /* format: channel_cpu */
 194         asprintf(&cmd, "%s %s_0", "get_n_subbufs", channel);
 195
 196         result = ustcmd_send_cmd(cmd, pid, &reply);
 197         if (result) {
 198                 free(cmd);
 199                 free(reply);
 200                 return -1;
 201         }
 202
 203         result = atoi(reply);
 204         free(cmd);
 205         free(reply);
 206         return result;
 207 }
 208
 209 /**
 210  * Destroys an UST trace according to a PID.
 211  *
 212  * @param pid   Traced process ID
 213  * @return      0 if successful, or error USTCMD_ERR_GEN
 214  */
 215 int ustcmd_destroy_trace(pid_t pid)
 216 {
 217         int result;
 218
 219         result = ustcmd_send_cmd("trace_destroy", pid, NULL);
 220         if (result != 1) {
 221                 return USTCMD_ERR_GEN;
 222         }
 223
 224         return 0;
 225 }
 226
 227 /**
 228  * Starts an UST trace (and setups it) 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_setup_and_start(pid_t pid)
 234 {
 235         int result;
 236
 237         result = ustcmd_send_cmd("start", pid, NULL);
 238         if (result != 1) {
 239                 return USTCMD_ERR_GEN;
 240         }
 241
 242         return 0;
 243 }
 244
 245 /**
 246  * Creates an UST trace 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_create_trace(pid_t pid)
 252 {
 253         int result;
 254
 255         result = ustcmd_send_cmd("trace_create", pid, NULL);
 256         if (result != 1) {
 257                 return USTCMD_ERR_GEN;
 258         }
 259
 260         return 0;
 261 }
 262
 263 /**
 264  * Starts 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_start_trace(pid_t pid)
 270 {
 271         int result;
 272
 273         result = ustcmd_send_cmd("trace_start", pid, NULL);
 274         if (result != 1) {
 275                 return USTCMD_ERR_GEN;
 276         }
 277
 278         return 0;
 279 }
 280
 281 /**
 282  * Alloc 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_alloc_trace(pid_t pid)
 288 {
 289         int result;
 290
 291         result = ustcmd_send_cmd("trace_alloc", pid, NULL);
 292         if (result != 1) {
 293                 return USTCMD_ERR_GEN;
 294         }
 295
 296         return 0;
 297 }
 298
 299 /**
 300  * Stops 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_stop_trace(pid_t pid)
 306 {
 307         int result;
 308
 309         result = ustcmd_send_cmd("trace_stop", pid, NULL);
 310         if (result != 1) {
 311                 return USTCMD_ERR_GEN;
 312         }
 313
 314         return 0;
 315 }
 316
 317 /**
 318  * Counts newlines ('\n') in a string.
 319  *
 320  * @param str   String to search in
 321  * @return      Total newlines count
 322  */
 323 unsigned int ustcmd_count_nl(const char *str)
 324 {
 325         unsigned int i = 0, tot = 0;
 326
 327         while (str[i] != '\0') {
 328                 if (str[i] == '\n') {
 329                         ++tot;
 330                 }
 331                 ++i;
 332         }
 333
 334         return tot;
 335 }
 336
 337 /**
 338  * Frees a CMSF array.
 339  *
 340  * @param cmsf  CMSF array to free
 341  * @return      0 if successful, or error USTCMD_ERR_ARG
 342  */
 343 int ustcmd_free_cmsf(struct marker_status *cmsf)
 344 {
 345         if (cmsf == NULL) {
 346                 return USTCMD_ERR_ARG;
 347         }
 348
 349         unsigned int i = 0;
 350         while (cmsf[i].channel != NULL) {
 351                 free(cmsf[i].channel);
 352                 free(cmsf[i].marker);
 353                 free(cmsf[i].fs);
 354                 ++i;
 355         }
 356         free(cmsf);
 357
 358         return 0;
 359 }
 360
 361 /**
 362  * Gets channel/marker/state/format string for a given PID.
 363  *
 364  * @param cmsf  Pointer to CMSF array to be filled (callee allocates, caller
 365  *              frees with `ustcmd_free_cmsf')
 366  * @param pid   Targeted PID
 367  * @return      0 if successful, or -1 on error
 368  */
 369 int ustcmd_get_cmsf(struct marker_status **cmsf, const pid_t pid)
 370 {
 371         char *big_str = NULL;
 372         int result;
 373         struct marker_status *tmp_cmsf = NULL;
 374         unsigned int i = 0, cmsf_ind = 0;
 375
 376         if (cmsf == NULL) {
 377                 return -1;
 378         }
 379         result = ustcmd_send_cmd("list_markers", pid, &big_str);
 380         if (result != 1) {
 381                 return -1;
 382         }
 383
 384         if (result != 1) {
 385                 ERR("error while getting markers list");
 386                 return -1;
 387         }
 388
 389         tmp_cmsf = (struct marker_status *) malloc(sizeof(struct marker_status) *
 390                 (ustcmd_count_nl(big_str) + 1));
 391         if (tmp_cmsf == NULL) {
 392                 return -1;
 393         }
 394
 395         /* Parse received reply string (format: "[chan]/[mark] [st] [fs]"): */
 396         while (big_str[i] != '\0') {
 397                 char state;
 398
 399                 sscanf(big_str + i, "marker: %a[^/]/%a[^ ] %c %a[^\n]",
 400                         &tmp_cmsf[cmsf_ind].channel,
 401                         &tmp_cmsf[cmsf_ind].marker,
 402                         &state,
 403                         &tmp_cmsf[cmsf_ind].fs);
 404                 tmp_cmsf[cmsf_ind].state = (state == USTCMD_MS_CHR_ON ?
 405                         USTCMD_MS_ON : USTCMD_MS_OFF); /* Marker state */
 406
 407                 while (big_str[i] != '\n') {
 408                         ++i; /* Go to next '\n' */
 409                 }
 410                 ++i; /* Skip current pointed '\n' */
 411                 ++cmsf_ind;
 412         }
 413         tmp_cmsf[cmsf_ind].channel = NULL;
 414         tmp_cmsf[cmsf_ind].marker = NULL;
 415         tmp_cmsf[cmsf_ind].fs = NULL;
 416
 417         *cmsf = tmp_cmsf;
 418
 419         free(big_str);
 420         return 0;
 421 }
 422
 423 /**
 424  * Sends a given command to a traceable process
 425  *
 426  * @param cmd   Null-terminated command to send
 427  * @param pid   Targeted PID
 428  * @param reply Pointer to string to be filled with a reply string (must
 429  *              be NULL if no reply is needed for the given command).
 430  * @return      -1 if successful, 0 on EOT, 1 on success
 431  */
 432
 433 int ustcmd_send_cmd(const char *cmd, const pid_t pid, char **reply)
 434 {
 435         struct ustcomm_connection conn;
 436         int retval;
 437
 438         if (ustcomm_connect_app(pid, &conn)) {
 439                 ERR("could not connect to PID %u", (unsigned int) pid);
 440                 return -1;
 441         }
 442
 443         retval = ustcomm_send_request(&conn, cmd, reply);
 444
 445         ustcomm_close_app(&conn);
 446
 447         return retval;
 448 }