#define PUT_SUBBUF_OK 1
#define PUT_SUBBUF_DIED 0
#define PUT_SUBBUF_PUSHED 2
+#define PUT_SUBBUF_DONE 3
char *sock_path=NULL;
char *trace_path=NULL;
int active_buffers = 0;
pthread_mutex_t active_buffers_mutex = PTHREAD_MUTEX_INITIALIZER;
/* Whether a request to end the program was received. */
-sig_atomic_t terminate_req = 0;
+volatile sig_atomic_t terminate_req = 0;
int get_subbuffer(struct buffer_info *buf)
{
asprintf(&send_msg, "get_subbuffer %s", buf->name);
result = ustcomm_send_request(&buf->conn, send_msg, &received_msg);
- if((result == -1 && errno == EPIPE) || result == 0) {
+ if((result == -1 && (errno == ECONNRESET || errno == EPIPE)) || result == 0) {
DBG("app died while being traced");
retval = GET_SUBBUF_DIED;
goto end;
if(result != 2 && result != 1) {
ERR("unable to parse response to get_subbuffer");
retval = -1;
+ free(received_msg);
goto end_rep;
}
- DBG("received msg is %s", received_msg);
-
if(!strcmp(rep_code, "OK")) {
DBG("got subbuffer %s", buf->name);
retval = GET_SUBBUF_OK;
retval = GET_SUBBUF_DONE;
goto end_rep;
}
+ else if(!strcmp(received_msg, "NOTFOUND")) {
+ DBG("For buffer %s, the trace was not found. This likely means it was destroyed by the user.", buf->name);
+ retval = GET_SUBBUF_DIED;
+ goto end_rep;
+ }
else {
DBG("error getting subbuffer %s", buf->name);
retval = -1;
asprintf(&send_msg, "put_subbuffer %s %ld", buf->name, buf->consumed_old);
result = ustcomm_send_request(&buf->conn, send_msg, &received_msg);
- if(result < 0 && errno == ECONNRESET) {
+ if(result < 0 && (errno == ECONNRESET || errno == EPIPE)) {
retval = PUT_SUBBUF_DIED;
goto end;
}
- if(result < 0) {
+ else if(result < 0) {
ERR("put_subbuffer: send_message failed");
retval = -1;
goto end;
}
+ else if(result == 0) {
+ /* Program seems finished. However this might not be
+ * the last subbuffer that has to be collected.
+ */
+ retval = PUT_SUBBUF_DIED;
+ goto end;
+ }
result = sscanf(received_msg, "%as", &rep_code);
if(result != 1) {
DBG("subbuffer put %s", buf->name);
retval = PUT_SUBBUF_OK;
}
+ else if(!strcmp(received_msg, "NOTFOUND")) {
+ DBG("For buffer %s, the trace was not found. This likely means it was destroyed by the user.", buf->name);
+ /* However, maybe this was not the last subbuffer. So
+ * we return the program died.
+ */
+ retval = PUT_SUBBUF_DIED;
+ goto end_rep;
+ }
else {
DBG("put_subbuffer: received error, we were pushed");
retval = PUT_SUBBUF_PUSHED;
ERR("problem in ustcomm_send_request(get_pidunique)");
return NULL;
}
+ if(result == 0) {
+ goto error;
+ }
result = sscanf(received_msg, "%lld", &buf->pidunique);
if(result != 1) {
ERR("problem in ustcomm_send_request(get_shmid)");
return NULL;
}
+ if(result == 0) {
+ goto error;
+ }
result = sscanf(received_msg, "%d %d", &buf->shmid, &buf->bufstruct_shmid);
if(result != 2) {
- ERR("unable to parse response to get_shmid");
+ ERR("unable to parse response to get_shmid (\"%s\")", received_msg);
return NULL;
}
free(received_msg);
ERR("problem in ustcomm_send_request(g_n_subbufs)");
return NULL;
}
+ if(result == 0) {
+ goto error;
+ }
result = sscanf(received_msg, "%d", &buf->n_subbufs);
if(result != 1) {
/* get subbuf size */
asprintf(&send_msg, "get_subbuf_size %s", buf->name);
- ustcomm_send_request(&buf->conn, send_msg, &received_msg);
+ result = ustcomm_send_request(&buf->conn, send_msg, &received_msg);
free(send_msg);
+ if(result == -1) {
+ ERR("problem in ustcomm_send_request(get_subbuf_size)");
+ return NULL;
+ }
+ if(result == 0) {
+ goto error;
+ }
result = sscanf(received_msg, "%d", &buf->subbuf_size);
if(result != 1) {
}
free(tmp);
- asprintf(&tmp, "%s/%u_%lld/%s_0", trace_path, buf->pid, buf->pidunique, buf->name);
+ asprintf(&tmp, "%s/%u_%lld/%s", trace_path, buf->pid, buf->pidunique, buf->name);
result = fd = open(tmp, O_WRONLY | O_CREAT | O_TRUNC | O_EXCL, 00600);
if(result == -1) {
PERROR("open");
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");
+ return -1;
+ }
+
+ return 0;
}
int consumer_loop(struct buffer_info *buf)
}
/* write data to file */
- result = patient_write(buf->file_fd, buf->mem + (buf->consumed_old & (buf->n_subbufs * buf->subbuf_size-1)), buf->subbuf_size);
+ result = write_current_subbuffer(buf);
if(result == -1) {
- PERROR("write");
- /* FIXME: maybe drop this trace */
+ ERR("Failed writing a subbuffer to file (channel=%s). Dropping this buffer.", buf->name);
}
/* put the subbuffer */
- /* FIXME: we actually should unput the buffer before consuming... */
result = put_subbuffer(buf);
if(result == -1) {
ERR("unknown error putting subbuffer (channel=%s)", buf->name);
break;
}
else if(result == PUT_SUBBUF_DIED) {
- WARN("application died while putting subbuffer");
- /* FIXME: probably need to skip the first subbuffer in finish_consuming_dead_subbuffer */
+ 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) {
}
}
return 0;
}
-void free_buffer(struct buffer_info *buf)
-{
-}
-
struct consumer_thread_args {
pid_t pid;
const char *bufname;
consumer_loop(buf);
- free_buffer(buf);
+ free((void *)args->bufname);
+ destroy_buffer(buf);
end:
- /* bufname is free'd in free_buffer() */
free(args);
return NULL;
}
{
pthread_t thr;
struct consumer_thread_args *args;
+ int result;
DBG("beginning of start_consuming_buffer: args: pid %d bufname %s", pid, bufname);
args->bufname = strdup(bufname);
DBG("beginning2 of start_consuming_buffer: args: pid %d bufname %s", args->pid, args->bufname);
- pthread_create(&thr, NULL, consumer_thread, args);
+ 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);
return 0;
PERROR("sigaction");
return 1;
}
+ result = sigaction(SIGINT, &sa, NULL);
+ if(result == -1) {
+ PERROR("sigaction");
+ return 1;
+ }
result = ustcomm_init_ustd(&ustd, sock_path);
if(result == -1) {
free_bufname:
free(bufname);
}
+ else {
+ WARN("unknown command: %s", recvbuf);
+ }
free(recvbuf);
}
}
}
+ ustcomm_fini_ustd(&ustd);
+
return 0;
}