+
+int kernel_track_pid(struct ltt_kernel_session *session, int pid)
+{
+ int ret;
+
+ DBG("Kernel track PID %d for session id %" PRIu64 ".",
+ pid, session->id);
+ ret = kernctl_track_pid(session->fd, pid);
+ if (!ret) {
+ return LTTNG_OK;
+ }
+ switch (errno) {
+ case EINVAL:
+ return LTTNG_ERR_INVALID;
+ case ENOMEM:
+ return LTTNG_ERR_NOMEM;
+ case EEXIST:
+ return LTTNG_ERR_PID_TRACKED;
+ default:
+ return LTTNG_ERR_UNK;
+ }
+}
+
+int kernel_untrack_pid(struct ltt_kernel_session *session, int pid)
+{
+ int ret;
+
+ DBG("Kernel untrack PID %d for session id %" PRIu64 ".",
+ pid, session->id);
+ ret = kernctl_untrack_pid(session->fd, pid);
+ if (!ret) {
+ return LTTNG_OK;
+ }
+ switch (errno) {
+ case EINVAL:
+ return LTTNG_ERR_INVALID;
+ case ENOMEM:
+ return LTTNG_ERR_NOMEM;
+ case ENOENT:
+ return LTTNG_ERR_PID_NOT_TRACKED;
+ default:
+ return LTTNG_ERR_UNK;
+ }
+}
+
+ssize_t kernel_list_tracker_pids(struct ltt_kernel_session *session,
+ int **_pids)
+{
+ int fd, ret;
+ int pid;
+ ssize_t nbmem, count = 0;
+ FILE *fp;
+ int *pids;
+
+ fd = kernctl_list_tracker_pids(session->fd);
+ if (fd < 0) {
+ PERROR("kernel tracker pids list");
+ goto error;
+ }
+
+ fp = fdopen(fd, "r");
+ if (fp == NULL) {
+ PERROR("kernel tracker pids list fdopen");
+ goto error_fp;
+ }
+
+ nbmem = KERNEL_TRACKER_PIDS_INIT_LIST_SIZE;
+ pids = zmalloc(sizeof(*pids) * nbmem);
+ if (pids == NULL) {
+ PERROR("alloc list pids");
+ count = -ENOMEM;
+ goto end;
+ }
+
+ while (fscanf(fp, "process { pid = %u; };\n", &pid) == 1) {
+ if (count >= nbmem) {
+ int *new_pids;
+ size_t new_nbmem;
+
+ new_nbmem = nbmem << 1;
+ DBG("Reallocating pids list from %zu to %zu entries",
+ nbmem, new_nbmem);
+ new_pids = realloc(pids, new_nbmem * sizeof(*new_pids));
+ if (new_pids == NULL) {
+ PERROR("realloc list events");
+ free(pids);
+ count = -ENOMEM;
+ goto end;
+ }
+ /* Zero the new memory */
+ memset(new_pids + nbmem, 0,
+ (new_nbmem - nbmem) * sizeof(*new_pids));
+ nbmem = new_nbmem;
+ pids = new_pids;
+ }
+ pids[count++] = pid;
+ }
+
+ *_pids = pids;
+ DBG("Kernel list tracker pids done (%zd pids)", count);
+end:
+ ret = fclose(fp); /* closes both fp and fd */
+ if (ret) {
+ PERROR("fclose");
+ }
+ return count;
+
+error_fp:
+ ret = close(fd);
+ if (ret) {
+ PERROR("close");
+ }
+error:
+ return -1;
+}
+