X-Git-Url: https://git.lttng.org/?a=blobdiff_plain;f=ustd%2Fustd.c;h=8a1f4d60c2df6397cbccdd5af6d5b54a8849023f;hb=1eba9d6b2081a1e75e7f711ac02023dde773bef1;hp=d2a9712a20c1ca78cbe99cc6be7337be9c602e31;hpb=0ed54020dd215419ddb85dc059d983cff25e8729;p=ust.git

diff --git a/ustd/ustd.c b/ustd/ustd.c
index d2a9712..8a1f4d6 100644
--- a/ustd/ustd.c
+++ b/ustd/ustd.c
@@ -59,7 +59,7 @@ char *pidfile = 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)
 {
@@ -71,7 +71,7 @@ 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;
@@ -86,11 +86,10 @@ int get_subbuffer(struct buffer_info *buf)
 	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;
@@ -100,8 +99,8 @@ int get_subbuffer(struct buffer_info *buf)
 		goto end_rep;
 	}
 	else if(!strcmp(received_msg, "NOTFOUND")) {
-		WARN("For buffer %s, the trace was not found. This likely means it was destroyed by the user.", buf->name);
-		retval = GET_SUBBUF_DONE;
+		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 {
@@ -132,7 +131,7 @@ int put_subbuffer(struct buffer_info *buf)
 
 	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;
 	}
@@ -161,7 +160,7 @@ int put_subbuffer(struct buffer_info *buf)
 		retval = PUT_SUBBUF_OK;
 	}
 	else if(!strcmp(received_msg, "NOTFOUND")) {
-		WARN("For buffer %s, the trace was not found. This likely means it was destroyed by the user.", buf->name);
+		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.
 		 */
@@ -400,6 +399,52 @@ error:
 	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;
@@ -408,11 +453,19 @@ int write_current_subbuffer(struct buffer_info *buf)
 
 	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 0;
+		return -1;
 	}
 
 	return 0;
@@ -441,11 +494,12 @@ int consumer_loop(struct buffer_info *buf)
 		}
 
 		/* write data to file */
-		write_current_subbuffer(buf);
-		/* FIXME: handle return value? */
+		result = write_current_subbuffer(buf);
+		if(result == -1) {
+			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);
@@ -456,8 +510,11 @@ int consumer_loop(struct buffer_info *buf)
 			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;
 		}
@@ -483,10 +540,6 @@ int consumer_loop(struct buffer_info *buf)
 	return 0;
 }
 
-void free_buffer(struct buffer_info *buf)
-{
-}
-
 struct consumer_thread_args {
 	pid_t pid;
 	const char *bufname;
@@ -496,9 +549,33 @@ void *consumer_thread(void *arg)
 {
 	struct buffer_info *buf = (struct buffer_info *) arg;
 	struct consumer_thread_args *args = (struct consumer_thread_args *) arg;
+	int result;
+	sigset_t sigset;
 
 	DBG("GOT ARGS: pid %d bufname %s", args->pid, args->bufname);
 
+	/* Block signals that should be handled by the main thread. */
+	result = sigemptyset(&sigset);
+	if(result == -1) {
+		PERROR("sigemptyset");
+		goto end;
+	}
+	result = sigaddset(&sigset, SIGTERM);
+	if(result == -1) {
+		PERROR("sigaddset");
+		goto end;
+	}
+	result = sigaddset(&sigset, SIGINT);
+	if(result == -1) {
+		PERROR("sigaddset");
+		goto end;
+	}
+	result = sigprocmask(SIG_BLOCK, &sigset, NULL);
+	if(result == -1) {
+		PERROR("sigprocmask");
+		goto end;
+	}
+
 	buf = connect_buffer(args->pid, args->bufname);
 	if(buf == NULL) {
 		ERR("failed to connect to buffer");
@@ -507,10 +584,10 @@ void *consumer_thread(void *arg)
 
 	consumer_loop(buf);
 
-	free_buffer(buf);
+	destroy_buffer(buf);
 
 	end:
-	/* bufname is free'd in free_buffer() */
+	free((void *)args->bufname);
 	free(args);
 	return NULL;
 }
@@ -519,6 +596,7 @@ 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);
 
@@ -528,7 +606,16 @@ int start_consuming_buffer(pid_t pid, const char *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;
@@ -630,6 +717,7 @@ int start_ustd(int fd)
 	int result;
 	sigset_t sigset;
 	struct sigaction sa;
+	int timeout = -1;
 
 	result = sigemptyset(&sigset);
 	if(result == -1) {
@@ -638,12 +726,17 @@ int start_ustd(int fd)
 	}
 	sa.sa_handler = sigterm_handler;
 	sa.sa_mask = sigset;
-	sa.sa_flags = SA_RESTART;
+	sa.sa_flags = 0;
 	result = sigaction(SIGTERM, &sa, NULL);
 	if(result == -1) {
 		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) {
@@ -700,12 +793,15 @@ int start_ustd(int fd)
 		char *recvbuf;
 
 		/* check for requests on our public socket */
-		result = ustcomm_ustd_recv_message(&ustd, &recvbuf, NULL, 100);
-		if(result == -1) {
+		result = ustcomm_ustd_recv_message(&ustd, &recvbuf, NULL, timeout);
+		if(result == -1 && errno == EINTR) {
+			/* Caught signal */
+		}
+		else if(result == -1) {
 			ERR("error in ustcomm_ustd_recv_message");
 			goto loop_end;
 		}
-		if(result > 0) {
+		else if(result > 0) {
 			if(!strncmp(recvbuf, "collect", 7)) {
 				pid_t pid;
 				char *bufname;
@@ -726,6 +822,9 @@ int start_ustd(int fd)
 				free_bufname:
 				free(bufname);
 			}
+			else {
+				WARN("unknown command: %s", recvbuf);
+			}
 
 			free(recvbuf);
 		}
@@ -739,9 +838,12 @@ int start_ustd(int fd)
 				break;
 			}
 			pthread_mutex_unlock(&active_buffers_mutex);
+			timeout = 100;
 		}
 	}
 
+	ustcomm_fini_ustd(&ustd);
+
 	return 0;
 }