+ pthread_mutex_lock(&active_buffers_mutex);
+ active_buffers++;
+ pthread_mutex_unlock(&active_buffers_mutex);
+
+ return buf;
+
+error:
+ free(buf);
+ return NULL;
+}
+
+static void destroy_buffer(struct buffer_info *buf)
+{
+ int result;
+
+ result = ustcomm_close_app(&buf->conn);
+ if(result == -1) {
+ WARN("problem calling ustcomm_close_app");
+ }
+
+ result = shmdt(buf->mem);
+ if(result == -1) {
+ PERROR("shmdt");
+ }
+
+ result = shmdt(buf->bufstruct_mem);
+ if(result == -1) {
+ PERROR("shmdt");
+ }
+
+ result = close(buf->file_fd);
+ if(result == -1) {
+ PERROR("close");
+ }
+
+ free(buf);
+}
+
+int unwrite_last_subbuffer(struct buffer_info *buf)
+{
+ int result;
+
+ result = ftruncate(buf->file_fd, buf->previous_offset);
+ if(result == -1) {
+ PERROR("ftruncate");
+ return -1;
+ }
+
+ result = lseek(buf->file_fd, buf->previous_offset, SEEK_SET);
+ if(result == (int)(off_t)-1) {
+ PERROR("lseek");
+ return -1;
+ }
+
+ return 0;
+}
+
+int write_current_subbuffer(struct buffer_info *buf)
+{
+ int result;
+
+ void *subbuf_mem = buf->mem + (buf->consumed_old & (buf->n_subbufs * buf->subbuf_size-1));
+
+ size_t cur_sb_size = subbuffer_data_size(subbuf_mem);
+
+ off_t cur_offset = lseek(buf->file_fd, 0, SEEK_CUR);
+ if(cur_offset == (off_t)-1) {
+ PERROR("lseek");
+ return -1;
+ }
+
+ buf->previous_offset = cur_offset;
+ DBG("previous_offset: %ld", cur_offset);
+
+ result = patient_write(buf->file_fd, subbuf_mem, cur_sb_size);
+ if(result == -1) {
+ PERROR("write");
+ /* FIXME: maybe drop this trace */
+ return -1;
+ }
+
+ return 0;
+}
+
+int consumer_loop(struct buffer_info *buf)
+{
+ int result;
+
+ pthread_cleanup_push(decrement_active_buffers, NULL);
+
+ for(;;) {
+ /* get the subbuffer */
+ result = get_subbuffer(buf);
+ if(result == -1) {
+ ERR("error getting subbuffer");
+ continue;
+ }
+ else if(result == GET_SUBBUF_DONE) {
+ /* this is done */
+ break;
+ }
+ else if(result == GET_SUBBUF_DIED) {
+ finish_consuming_dead_subbuffer(buf);
+ break;
+ }
+
+ /* write data to file */
+ write_current_subbuffer(buf);
+ /* FIXME: handle return value? */
+
+ /* put the subbuffer */
+ result = put_subbuffer(buf);
+ if(result == -1) {
+ ERR("unknown error putting subbuffer (channel=%s)", buf->name);
+ break;
+ }
+ else if(result == PUT_SUBBUF_PUSHED) {
+ ERR("Buffer overflow (channel=%s), reader pushed. This channel will not be usable passed this point.", buf->name);
+ break;
+ }
+ else if(result == PUT_SUBBUF_DIED) {
+ DBG("application died while putting subbuffer");
+ /* Skip the first subbuffer. We are not sure it is trustable
+ * because the put_subbuffer() did not complete.
+ */
+ unwrite_last_subbuffer(buf);
+ finish_consuming_dead_subbuffer(buf);
+ break;
+ }
+ else if(result == PUT_SUBBUF_DONE) {
+ /* Done with this subbuffer */
+ /* FIXME: add a case where this branch is used? Upon
+ * normal trace termination, at put_subbuf time, a
+ * special last-subbuffer code could be returned by
+ * the listener.
+ */
+ break;
+ }
+ else if(result == PUT_SUBBUF_OK) {
+ }
+ }
+
+ DBG("thread for buffer %s is stopping", buf->name);
+
+ /* FIXME: destroy, unalloc... */
+
+ pthread_cleanup_pop(1);
+
+ return 0;
+}
+
+struct consumer_thread_args {
+ pid_t pid;
+ const char *bufname;
+};
+
+void *consumer_thread(void *arg)
+{
+ struct buffer_info *buf = (struct buffer_info *) arg;
+ struct consumer_thread_args *args = (struct consumer_thread_args *) arg;
+
+ DBG("GOT ARGS: pid %d bufname %s", args->pid, args->bufname);
+
+ buf = connect_buffer(args->pid, args->bufname);
+ if(buf == NULL) {
+ ERR("failed to connect to buffer");
+ goto end;
+ }
+
+ consumer_loop(buf);
+
+ free((void *)args->bufname);
+ destroy_buffer(buf);
+
+ end:
+ free(args);
+ return NULL;
+}
+
+int start_consuming_buffer(pid_t pid, const char *bufname)
+{
+ pthread_t thr;
+ struct consumer_thread_args *args;
+ int result;
+
+ DBG("beginning of start_consuming_buffer: args: pid %d bufname %s", pid, bufname);
+
+ args = (struct consumer_thread_args *) malloc(sizeof(struct consumer_thread_args));
+
+ args->pid = pid;
+ args->bufname = strdup(bufname);
+ DBG("beginning2 of start_consuming_buffer: args: pid %d bufname %s", args->pid, args->bufname);
+
+ result = pthread_create(&thr, NULL, consumer_thread, args);
+ if(result == -1) {
+ ERR("pthread_create failed");
+ return -1;
+ }
+ result = pthread_detach(thr);
+ if(result == -1) {
+ ERR("pthread_detach failed");
+ return -1;
+ }
+ DBG("end of start_consuming_buffer: args: pid %d bufname %s", args->pid, args->bufname);