Fix: add missing SIGTERM and SIGINT handler

Handle expected signals gracefully: stop processing at cancellation
points expected by the protocol, so the relay daemon does not print
error messages when clients quit gracefully.

Signed-off-by: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>

diff --git a/formats/lttng-live/lttng-live-comm.c b/formats/lttng-live/lttng-live-comm.c
index 2d4a13761b21d4e6733ff1f8e20593ab2f77c021..fee43c2bed51a8c647d8138f696117df5361fb42 100644 (file)
--- a/formats/lttng-live/lttng-live-comm.c
+++ b/formats/lttng-live/lttng-live-comm.c
@@ -113,16 +113,21 @@ int lttng_live_connect_viewer(struct lttng_live_ctx *ctx)
        struct sockaddr_in server_addr;
        int ret;
 
-       host = gethostbyname(ctx->relay_hostname);
-       if (!host) {
+       if (lttng_live_should_quit()) {
                ret = -1;
                goto end;
        }
 
+       host = gethostbyname(ctx->relay_hostname);
+       if (!host) {
+               fprintf(stderr, "[error] Cannot lookup hostname %s\n",
+                       ctx->relay_hostname);
+               goto error;
+       }
+
        if ((ctx->control_sock = socket(AF_INET, SOCK_STREAM, 0)) == -1) {
                perror("Socket");
-               ret = -1;
-               goto end;
+               goto error;
        }
 
        server_addr.sin_family = AF_INET;
@@ -133,14 +138,17 @@ int lttng_live_connect_viewer(struct lttng_live_ctx *ctx)
        if (connect(ctx->control_sock, (struct sockaddr *) &server_addr,
                                sizeof(struct sockaddr)) == -1) {
                perror("Connect");
-               ret = -1;
-               goto end;
+               goto error;
        }
 
        ret = 0;
 
 end:
        return ret;
+
+error:
+       fprintf(stderr, "[error] Connection failed\n");
+       return -1;
 }
 
 int lttng_live_establish_connection(struct lttng_live_ctx *ctx)
@@ -150,6 +158,11 @@ int lttng_live_establish_connection(struct lttng_live_ctx *ctx)
        int ret;
        ssize_t ret_len;
 
+       if (lttng_live_should_quit()) {
+               ret = -1;
+               goto end;
+       }
+
        cmd.cmd = htobe32(LTTNG_VIEWER_CONNECT);
        cmd.data_size = sizeof(connect);
        cmd.cmd_version = 0;
@@ -162,7 +175,6 @@ int lttng_live_establish_connection(struct lttng_live_ctx *ctx)
        ret_len = lttng_live_send(ctx->control_sock, &cmd, sizeof(cmd));
        if (ret_len < 0) {
                perror("[error] Error sending cmd");
-               ret = ret_len;
                goto error;
        }
        assert(ret_len == sizeof(cmd));
@@ -170,7 +182,6 @@ int lttng_live_establish_connection(struct lttng_live_ctx *ctx)
        ret_len = lttng_live_send(ctx->control_sock, &connect, sizeof(connect));
        if (ret_len < 0) {
                perror("[error] Error sending version");
-               ret = ret_len;
                goto error;
        }
        assert(ret_len == sizeof(connect));
@@ -178,12 +189,10 @@ int lttng_live_establish_connection(struct lttng_live_ctx *ctx)
        ret_len = lttng_live_recv(ctx->control_sock, &connect, sizeof(connect));
        if (ret_len == 0) {
                fprintf(stderr, "[error] Remote side has closed connection\n");
-               ret = -1;
                goto error;
        }
        if (ret_len < 0) {
                perror("[error] Error receiving version");
-               ret = ret_len;
                goto error;
        }
        assert(ret_len == sizeof(connect));
@@ -192,11 +201,13 @@ int lttng_live_establish_connection(struct lttng_live_ctx *ctx)
                        be64toh(connect.viewer_session_id));
        printf_verbose("Relayd version : %u.%u\n", be32toh(connect.major),
                        be32toh(connect.minor));
-
        ret = 0;
+end:
+       return ret;
 
 error:
-       return ret;
+       fprintf(stderr, "[error] Unable to establish connection\n");
+       return -1;
 }
 
 static
@@ -271,6 +282,11 @@ int lttng_live_list_sessions(struct lttng_live_ctx *ctx, const char *path)
        uint64_t session_id;
        GPtrArray *session_list = NULL;
 
+       if (lttng_live_should_quit()) {
+               ret = -1;
+               goto end;
+       }
+
        if (strlen(ctx->session_name) == 0) {
                print_list = 1;
                session_list = g_ptr_array_new();
@@ -283,7 +299,6 @@ int lttng_live_list_sessions(struct lttng_live_ctx *ctx, const char *path)
        ret_len = lttng_live_send(ctx->control_sock, &cmd, sizeof(cmd));
        if (ret_len < 0) {
                perror("[error] Error sending cmd");
-               ret = ret_len;
                goto error;
        }
        assert(ret_len == sizeof(cmd));
@@ -291,12 +306,10 @@ int lttng_live_list_sessions(struct lttng_live_ctx *ctx, const char *path)
        ret_len = lttng_live_recv(ctx->control_sock, &list, sizeof(list));
        if (ret_len == 0) {
                fprintf(stderr, "[error] Remote side has closed connection\n");
-               ret = -1;
                goto error;
        }
        if (ret_len < 0) {
                perror("[error] Error receiving session list");
-               ret = ret_len;
                goto error;
        }
        assert(ret_len == sizeof(list));
@@ -306,12 +319,10 @@ int lttng_live_list_sessions(struct lttng_live_ctx *ctx, const char *path)
                ret_len = lttng_live_recv(ctx->control_sock, &lsession, sizeof(lsession));
                if (ret_len == 0) {
                        fprintf(stderr, "[error] Remote side has closed connection\n");
-                       ret = -1;
                        goto error;
                }
                if (ret_len < 0) {
                        perror("[error] Error receiving session");
-                       ret = ret_len;
                        goto error;
                }
                assert(ret_len == sizeof(lsession));
@@ -342,11 +353,13 @@ int lttng_live_list_sessions(struct lttng_live_ctx *ctx, const char *path)
                print_session_list(session_list, path);
                free_session_list(session_list);
        }
-
        ret = 0;
+end:
+       return ret;
 
 error:
-       return ret;
+       fprintf(stderr, "[error] Unable to list sessions\n");
+       return -1;
 }
 
 int lttng_live_ctf_trace_assign(struct lttng_live_viewer_stream *stream,
@@ -399,6 +412,11 @@ int lttng_live_attach_session(struct lttng_live_ctx *ctx, uint64_t id)
        int ret, i;
        ssize_t ret_len;
 
+       if (lttng_live_should_quit()) {
+               ret = -1;
+               goto end;
+       }
+
        cmd.cmd = htobe32(LTTNG_VIEWER_ATTACH_SESSION);
        cmd.data_size = sizeof(rq);
        cmd.cmd_version = 0;
@@ -412,7 +430,6 @@ int lttng_live_attach_session(struct lttng_live_ctx *ctx, uint64_t id)
        ret_len = lttng_live_send(ctx->control_sock, &cmd, sizeof(cmd));
        if (ret_len < 0) {
                perror("[error] Error sending cmd");
-               ret = ret_len;
                goto error;
        }
        assert(ret_len == sizeof(cmd));
@@ -420,7 +437,6 @@ int lttng_live_attach_session(struct lttng_live_ctx *ctx, uint64_t id)
        ret_len = lttng_live_send(ctx->control_sock, &rq, sizeof(rq));
        if (ret_len < 0) {
                perror("[error] Error sending attach request");
-               ret = ret_len;
                goto error;
        }
        assert(ret_len == sizeof(rq));
@@ -428,12 +444,10 @@ int lttng_live_attach_session(struct lttng_live_ctx *ctx, uint64_t id)
        ret_len = lttng_live_recv(ctx->control_sock, &rp, sizeof(rp));
        if (ret_len == 0) {
                fprintf(stderr, "[error] Remote side has closed connection\n");
-               ret = -1;
                goto error;
        }
        if (ret_len < 0) {
                perror("[error] Error receiving attach response");
-               ret = ret_len;
                goto error;
        }
        assert(ret_len == sizeof(rp));
@@ -446,25 +460,20 @@ int lttng_live_attach_session(struct lttng_live_ctx *ctx, uint64_t id)
                goto end;
        case LTTNG_VIEWER_ATTACH_ALREADY:
                fprintf(stderr, "[error] There is already a viewer attached to this session\n");
-               ret = -1;
-               goto end;
+               goto error;
        case LTTNG_VIEWER_ATTACH_NOT_LIVE:
                fprintf(stderr, "[error] Not a live session\n");
-               ret = -1;
-               goto end;
+               goto error;
        case LTTNG_VIEWER_ATTACH_SEEK_ERR:
                fprintf(stderr, "[error] Wrong seek parameter\n");
-               ret = -1;
-               goto end;
+               goto error;
        default:
                fprintf(stderr, "[error] Unknown attach return code %u\n",
                                be32toh(rp.status));
-               ret = -1;
-               goto end;
+               goto error;
        }
        if (be32toh(rp.status) != LTTNG_VIEWER_ATTACH_OK) {
-               ret = -1;
-               goto end;
+               goto error;
        }
 
        ctx->session->stream_count += be32toh(rp.streams_count);
@@ -485,12 +494,10 @@ int lttng_live_attach_session(struct lttng_live_ctx *ctx, uint64_t id)
                ret_len = lttng_live_recv(ctx->control_sock, &stream, sizeof(stream));
                if (ret_len == 0) {
                        fprintf(stderr, "[error] Remote side has closed connection\n");
-                       ret = -1;
                        goto error;
                }
                if (ret_len < 0) {
                        perror("[error] Error receiving stream");
-                       ret = ret_len;
                        goto error;
                }
                assert(ret_len == sizeof(stream));
@@ -517,10 +524,11 @@ int lttng_live_attach_session(struct lttng_live_ctx *ctx, uint64_t id)
 
        }
        ret = 0;
-
 end:
-error:
        return ret;
+
+error:
+       return -1;
 }
 
 static
@@ -613,6 +621,10 @@ int get_data_packet(struct lttng_live_ctx *ctx,
        int ret;
 
 retry:
+       if (lttng_live_should_quit()) {
+               ret = -1;
+               goto end;
+       }
        cmd.cmd = htobe32(LTTNG_VIEWER_GET_PACKET);
        cmd.data_size = sizeof(rq);
        cmd.cmd_version = 0;
@@ -626,7 +638,6 @@ retry:
        ret_len = lttng_live_send(ctx->control_sock, &cmd, sizeof(cmd));
        if (ret_len < 0) {
                perror("[error] Error sending cmd");
-               ret = ret_len;
                goto error;
        }
        assert(ret_len == sizeof(cmd));
@@ -634,7 +645,6 @@ retry:
        ret_len = lttng_live_send(ctx->control_sock, &rq, sizeof(rq));
        if (ret_len < 0) {
                perror("[error] Error sending get_data_packet request");
-               ret = ret_len;
                goto error;
        }
        assert(ret_len == sizeof(rq));
@@ -642,19 +652,16 @@ retry:
        ret_len = lttng_live_recv(ctx->control_sock, &rp, sizeof(rp));
        if (ret_len == 0) {
                fprintf(stderr, "[error] Remote side has closed connection\n");
-               ret = -1;
                goto error;
        }
        if (ret_len < 0) {
                perror("[error] Error receiving data response");
-               ret = ret_len;
                goto error;
        }
        if (ret_len != sizeof(rp)) {
                fprintf(stderr, "[error] get_data_packet: expected %" PRId64
                                ", received %" PRId64 "\n", sizeof(rp),
                                ret_len);
-               ret = -1;
                goto error;
        }
 
@@ -667,9 +674,9 @@ retry:
                                "\n", len);
                break;
        case LTTNG_VIEWER_GET_PACKET_RETRY:
+               /* Unimplemented by relay daemon */
                printf_verbose("get_data_packet: retry\n");
-               ret = -1;
-               goto end;
+               goto error;
        case LTTNG_VIEWER_GET_PACKET_ERR:
                if (rp.flags & LTTNG_VIEWER_FLAG_NEW_METADATA) {
                        printf_verbose("get_data_packet: new metadata needed\n");
@@ -690,20 +697,16 @@ retry:
                        goto retry;
                }
                fprintf(stderr, "[error] get_data_packet: error\n");
-               ret = -1;
-               goto end;
+               goto error;
        case LTTNG_VIEWER_GET_PACKET_EOF:
                ret = -2;
-               goto error;
+               goto end;
        default:
                printf_verbose("get_data_packet: unknown\n");
-               assert(0);
-               ret = -1;
-               goto end;
+               goto error;
        }
 
        if (len <= 0) {
-               ret = -1;
                goto end;
        }
 
@@ -716,7 +719,6 @@ retry:
                        ret = munmap_align(pos->base_mma);
                        if (ret) {
                                perror("[error] Unable to unmap old base");
-                               ret = -1;
                                goto error;
                        }
                        pos->base_mma = NULL;
@@ -727,7 +729,6 @@ retry:
                if (pos->base_mma == MAP_FAILED) {
                        perror("[error] mmap error");
                        pos->base_mma = NULL;
-                       ret = -1;
                        goto error;
                }
 
@@ -740,19 +741,19 @@ retry:
                        mmap_align_addr(pos->base_mma), len);
        if (ret_len == 0) {
                fprintf(stderr, "[error] Remote side has closed connection\n");
-               ret = -1;
                goto error;
        }
        if (ret_len < 0) {
                perror("[error] Error receiving trace packet");
-               ret = ret_len;
                goto error;
        }
        assert(ret_len == len);
        ret = 0;
 end:
-error:
        return ret;
+
+error:
+       return -1;
 }
 
 static
@@ -767,6 +768,11 @@ int get_one_metadata_packet(struct lttng_live_ctx *ctx,
        char *data = NULL;
        ssize_t ret_len;
 
+       if (lttng_live_should_quit()) {
+               ret = -1;
+               goto end;
+       }
+
        rq.stream_id = htobe64(metadata_stream->id);
        cmd.cmd = htobe32(LTTNG_VIEWER_GET_METADATA);
        cmd.data_size = sizeof(rq);
@@ -775,7 +781,6 @@ int get_one_metadata_packet(struct lttng_live_ctx *ctx,
        ret_len = lttng_live_send(ctx->control_sock, &cmd, sizeof(cmd));
        if (ret_len < 0) {
                perror("[error] Error sending cmd");
-               ret = ret_len;
                goto error;
        }
        assert(ret_len == sizeof(cmd));
@@ -783,7 +788,6 @@ int get_one_metadata_packet(struct lttng_live_ctx *ctx,
        ret_len = lttng_live_send(ctx->control_sock, &rq, sizeof(rq));
        if (ret_len < 0) {
                perror("[error] Error sending get_metadata request");
-               ret = ret_len;
                goto error;
        }
        assert(ret_len == sizeof(rq));
@@ -791,12 +795,10 @@ int get_one_metadata_packet(struct lttng_live_ctx *ctx,
        ret_len = lttng_live_recv(ctx->control_sock, &rp, sizeof(rp));
        if (ret_len == 0) {
                fprintf(stderr, "[error] Remote side has closed connection\n");
-               ret = -1;
                goto error;
        }
        if (ret_len < 0) {
                perror("[error] Error receiving metadata response");
-               ret = ret_len;
                goto error;
        }
        assert(ret_len == sizeof(rp));
@@ -811,39 +813,31 @@ int get_one_metadata_packet(struct lttng_live_ctx *ctx,
                        goto end;
                case LTTNG_VIEWER_METADATA_ERR:
                        printf_verbose("get_metadata : ERR\n");
-                       ret = -1;
-                       goto end;
+                       goto error;
                default:
                        printf_verbose("get_metadata : UNKNOWN\n");
-                       ret = -1;
-                       goto end;
+                       goto error;
        }
 
        len = be64toh(rp.len);
        printf_verbose("Writing %" PRIu64" bytes to metadata\n", len);
        if (len <= 0) {
-               ret = -1;
-               goto end;
+               goto error;
        }
 
        data = zmalloc(len);
        if (!data) {
                perror("relay data zmalloc");
-               ret = -1;
                goto error;
        }
        ret_len = lttng_live_recv(ctx->control_sock, data, len);
        if (ret_len == 0) {
                fprintf(stderr, "[error] Remote side has closed connection\n");
-               ret = -1;
-               free(data);
-               goto error;
+               goto error_free_data;
        }
        if (ret_len < 0) {
                perror("[error] Error receiving trace packet");
-               ret = ret_len;
-               free(data);
-               goto error;
+               goto error_free_data;
        }
        assert(ret_len == len);
 
@@ -853,19 +847,19 @@ int get_one_metadata_packet(struct lttng_live_ctx *ctx,
        } while (ret_len < 0 && errno == EINTR);
        if (ret_len < 0) {
                fprintf(stderr, "[error] Writing in the metadata fp\n");
-               free(data);
-               ret = ret_len;
-               goto error;
+               goto error_free_data;
        }
        assert(ret_len == len);
        metadata_stream->metadata_len += len;
+       free(data);
        ret = len;
+end:
+       return ret;
 
+error_free_data:
        free(data);
-
-end:
 error:
-       return ret;
+       return -1;
 }
 
 /*
@@ -939,10 +933,13 @@ int get_next_index(struct lttng_live_ctx *ctx,
        rq.stream_id = htobe64(viewer_stream->id);
 
 retry:
+       if (lttng_live_should_quit()) {
+               ret = -1;
+               goto end;
+       }
        ret_len = lttng_live_send(ctx->control_sock, &cmd, sizeof(cmd));
        if (ret_len < 0) {
                perror("[error] Error sending cmd");
-               ret = ret_len;
                goto error;
        }
        assert(ret_len == sizeof(cmd));
@@ -950,7 +947,6 @@ retry:
        ret_len = lttng_live_send(ctx->control_sock, &rq, sizeof(rq));
        if (ret_len < 0) {
                perror("[error] Error sending get_next_index request");
-               ret = ret_len;
                goto error;
        }
        assert(ret_len == sizeof(rq));
@@ -958,12 +954,10 @@ retry:
        ret_len = lttng_live_recv(ctx->control_sock, &rp, sizeof(rp));
        if (ret_len == 0) {
                fprintf(stderr, "[error] Remote side has closed connection\n");
-               ret = -1;
                goto error;
        }
        if (ret_len < 0) {
                perror("[error] Error receiving index response");
-               ret = ret_len;
                goto error;
        }
        assert(ret_len == sizeof(rp));
@@ -1011,18 +1005,17 @@ retry:
                break;
        case LTTNG_VIEWER_INDEX_ERR:
                fprintf(stderr, "[error] get_next_index: error\n");
-               ret = -1;
                goto error;
        default:
                fprintf(stderr, "[error] get_next_index: unkwown value\n");
-               ret = -1;
                goto error;
        }
-
        ret = 0;
+end:
+       return ret;
 
 error:
-       return ret;
+       return -1;
 }
 
 static
@@ -1166,6 +1159,11 @@ int lttng_live_create_viewer_session(struct lttng_live_ctx *ctx)
        int ret;
        ssize_t ret_len;
 
+       if (lttng_live_should_quit()) {
+               ret = -1;
+               goto end;
+       }
+
        cmd.cmd = htobe32(LTTNG_VIEWER_CREATE_SESSION);
        cmd.data_size = 0;
        cmd.cmd_version = 0;
@@ -1173,7 +1171,6 @@ int lttng_live_create_viewer_session(struct lttng_live_ctx *ctx)
        ret_len = lttng_live_send(ctx->control_sock, &cmd, sizeof(cmd));
        if (ret_len < 0) {
                perror("[error] Error sending cmd");
-               ret = ret_len;
                goto error;
        }
        assert(ret_len == sizeof(cmd));
@@ -1181,25 +1178,24 @@ int lttng_live_create_viewer_session(struct lttng_live_ctx *ctx)
        ret_len = lttng_live_recv(ctx->control_sock, &resp, sizeof(resp));
        if (ret_len == 0) {
                fprintf(stderr, "[error] Remote side has closed connection\n");
-               ret = -1;
                goto error;
        }
        if (ret_len < 0) {
                perror("[error] Error receiving create session reply");
-               ret = ret_len;
                goto error;
        }
        assert(ret_len == sizeof(resp));
 
        if (be32toh(resp.status) != LTTNG_VIEWER_CREATE_SESSION_OK) {
                fprintf(stderr, "[error] Error creating viewer session\n");
-               ret = -1;
                goto error;
        }
        ret = 0;
+end:
+       return ret;
 
 error:
-       return ret;
+       return -1;
 }
 
 static
@@ -1323,6 +1319,11 @@ int lttng_live_get_new_streams(struct lttng_live_ctx *ctx, uint64_t id)
        ssize_t ret_len;
        uint32_t stream_count;
 
+       if (lttng_live_should_quit()) {
+               ret = -1;
+               goto end;
+       }
+
        cmd.cmd = htobe32(LTTNG_VIEWER_GET_NEW_STREAMS);
        cmd.data_size = sizeof(rq);
        cmd.cmd_version = 0;
@@ -1333,7 +1334,6 @@ int lttng_live_get_new_streams(struct lttng_live_ctx *ctx, uint64_t id)
        ret_len = lttng_live_send(ctx->control_sock, &cmd, sizeof(cmd));
        if (ret_len < 0) {
                perror("[error] Error sending cmd");
-               ret = ret_len;
                goto error;
        }
        assert(ret_len == sizeof(cmd));
@@ -1341,7 +1341,6 @@ int lttng_live_get_new_streams(struct lttng_live_ctx *ctx, uint64_t id)
        ret_len = lttng_live_send(ctx->control_sock, &rq, sizeof(rq));
        if (ret_len < 0) {
                perror("[error] Error sending get_new_streams request");
-               ret = ret_len;
                goto error;
        }
        assert(ret_len == sizeof(rq));
@@ -1349,12 +1348,10 @@ int lttng_live_get_new_streams(struct lttng_live_ctx *ctx, uint64_t id)
        ret_len = lttng_live_recv(ctx->control_sock, &rp, sizeof(rp));
        if (ret_len == 0) {
                fprintf(stderr, "[error] Remote side has closed connection\n");
-               ret = -1;
                goto error;
        }
        if (ret_len < 0) {
                perror("[error] Error receiving get_new_streams response");
-               ret = ret_len;
                goto error;
        }
        assert(ret_len == sizeof(rp));
@@ -1370,13 +1367,11 @@ int lttng_live_get_new_streams(struct lttng_live_ctx *ctx, uint64_t id)
                goto end;
        case LTTNG_VIEWER_NEW_STREAMS_ERR:
                fprintf(stderr, "[error] get_new_streams error\n");
-               ret = -1;
-               goto end;
+               goto error;
        default:
                fprintf(stderr, "[error] Unknown return code %u\n",
                                be32toh(rp.status));
-               ret = -1;
-               goto end;
+               goto error;
        }
 
        stream_count = be32toh(rp.streams_count);
@@ -1398,12 +1393,10 @@ int lttng_live_get_new_streams(struct lttng_live_ctx *ctx, uint64_t id)
                ret_len = lttng_live_recv(ctx->control_sock, &stream, sizeof(stream));
                if (ret_len == 0) {
                        fprintf(stderr, "[error] Remote side has closed connection\n");
-                       ret = -1;
                        goto error;
                }
                if (ret_len < 0) {
                        perror("[error] Error receiving stream");
-                       ret = ret_len;
                        goto error;
                }
                assert(ret_len == sizeof(stream));
@@ -1430,10 +1423,11 @@ int lttng_live_get_new_streams(struct lttng_live_ctx *ctx, uint64_t id)
 
        }
        ret = 0;
-
 end:
-error:
        return ret;
+
+error:
+       return -1;
 }
 
 void lttng_live_read(struct lttng_live_ctx *ctx)
@@ -1495,8 +1489,13 @@ void lttng_live_read(struct lttng_live_ctx *ctx)
        for (;;) {
                int flags;
 
+               if (lttng_live_should_quit()) {
+                       goto end_free;
+               }
+
                while (!ctx->session->stream_count) {
-                       if (ctx->session_ids->len == 0) {
+                       if (lttng_live_should_quit()
+                                       || ctx->session_ids->len == 0) {
                                goto end_free;
                        }
                        ret = ask_new_streams(ctx);
@@ -1518,6 +1517,9 @@ void lttng_live_read(struct lttng_live_ctx *ctx)
                        goto end;
                }
                for (;;) {
+                       if (lttng_live_should_quit()) {
+                               goto end_free;
+                       }
                        event = bt_ctf_iter_read_event_flags(iter, &flags);
                        if (!(flags & BT_ITER_FLAG_RETRY)) {
                                if (!event) {

diff --git a/formats/lttng-live/lttng-live-plugin.c b/formats/lttng-live/lttng-live-plugin.c
index 83c0458289bc1e9e2b0d9ac024eeaf0c679f3dbc..d02b799a09d759e22504dee26112fb01d0ecdbf4 100644 (file)
--- a/formats/lttng-live/lttng-live-plugin.c
+++ b/formats/lttng-live/lttng-live-plugin.c
@@ -36,8 +36,59 @@
 #include <glib.h>
 #include <unistd.h>
 #include <stdlib.h>
+#include <signal.h>
 #include "lttng-live.h"
 
+static volatile int should_quit;
+
+int lttng_live_should_quit(void)
+{
+       return should_quit;
+}
+
+static
+void sighandler(int sig)
+{
+       switch (sig) {
+       case SIGTERM:
+       case SIGINT:
+               should_quit = 1;
+               break;
+       default:
+               break;
+       }
+}
+
+/*
+ * TODO: Eventually, this signal handler setup should be done at the
+ * plugin manager level, rather than within this plugin. Beware, we are
+ * not cleaning up the signal handler after plugin execution.
+ */
+static
+int setup_sighandler(void)
+{
+       struct sigaction sa;
+       sigset_t sigset;
+       int ret;
+
+       if ((ret = sigemptyset(&sigset)) < 0) {
+               perror("sigemptyset");
+               return ret;
+       }
+       sa.sa_handler = sighandler;
+       sa.sa_mask = sigset;
+       sa.sa_flags = 0;
+       if ((ret = sigaction(SIGTERM, &sa, NULL)) < 0) {
+               perror("sigaction");
+               return ret;
+       }
+       if ((ret = sigaction(SIGINT, &sa, NULL)) < 0) {
+               perror("sigaction");
+               return ret;
+       }
+       return 0;
+}
+
 /*
  * hostname parameter needs to hold NAME_MAX chars.
  */
@@ -153,10 +204,12 @@ static int lttng_live_open_trace_read(const char *path)
        if (ret < 0) {
                goto end_free;
        }
-
+       ret = setup_sighandler();
+       if (ret < 0) {
+               goto end_free;
+       }
        ret = lttng_live_connect_viewer(ctx);
        if (ret < 0) {
-               fprintf(stderr, "[error] Connection failed\n");
                goto end_free;
        }
        printf_verbose("LTTng-live connected to relayd\n");
@@ -169,7 +222,6 @@ static int lttng_live_open_trace_read(const char *path)
        printf_verbose("Listing sessions\n");
        ret = lttng_live_list_sessions(ctx, path);
        if (ret < 0) {
-               fprintf(stderr, "[error] List error\n");
                goto end_free;
        }
 
@@ -182,6 +234,10 @@ end_free:
        g_free(ctx->session);
        g_free(ctx->session->streams);
        g_free(ctx);
+
+       if (lttng_live_should_quit()) {
+               ret = 0;
+       }
        return ret;
 }
 

diff --git a/formats/lttng-live/lttng-live.h b/formats/lttng-live/lttng-live.h
index 09de20b92e1431bb92830bdded8aa9929ce36604..ae04e8979a18edd536e9bb5e3f7227322ccdee0a 100644 (file)
--- a/formats/lttng-live/lttng-live.h
+++ b/formats/lttng-live/lttng-live.h
@@ -87,5 +87,6 @@ int lttng_live_list_sessions(struct lttng_live_ctx *ctx, const char *path);
 int lttng_live_attach_session(struct lttng_live_ctx *ctx, uint64_t id);
 void lttng_live_read(struct lttng_live_ctx *ctx);
 int lttng_live_get_new_streams(struct lttng_live_ctx *ctx, uint64_t id);
+int lttng_live_should_quit(void);
 
 #endif /* _LTTNG_LIVE_H */