Handle application context cmd

[deliverable/lttng-ust.git] / liblttng-ust / lttng-ust-comm.c

diff --git a/liblttng-ust/lttng-ust-comm.c b/liblttng-ust/lttng-ust-comm.c
index e1426139d064984decf8066c6d096e121b556d7c..3108e3826a4ed80eda4f7e425e6f1b64b73a8b7f 100644 (file)
--- a/liblttng-ust/lttng-ust-comm.c
+++ b/liblttng-ust/lttng-ust-comm.c
@@ -329,6 +329,24 @@ extern void lttng_ring_buffer_client_discard_exit(void);
 extern void lttng_ring_buffer_client_discard_rt_exit(void);
 extern void lttng_ring_buffer_metadata_client_exit(void);
 
+ssize_t lttng_ust_read(int fd, void *buf, size_t len)
+{
+       ssize_t ret;
+       size_t copied = 0, to_copy = len;
+
+       do {
+               ret = read(fd, buf + copied, to_copy);
+               if (ret > 0) {
+                       copied += ret;
+                       to_copy -= ret;
+               }
+       } while ((ret > 0 && to_copy > 0)
+               || (ret < 0 && errno == EINTR));
+       if (ret > 0) {
+               ret = copied;
+       }
+       return ret;
+}
 /*
  * Returns the HOME directory path. Caller MUST NOT free(3) the returned
  * pointer.
@@ -570,19 +588,20 @@ int handle_message(struct sock_info *sock_info,
        const struct lttng_ust_objd_ops *ops;
        struct ustcomm_ust_reply lur;
        union ust_args args;
+       char ctxstr[LTTNG_UST_SYM_NAME_LEN];    /* App context string. */
        ssize_t len;
 
        memset(&lur, 0, sizeof(lur));
 
        if (ust_lock()) {
                ret = -LTTNG_UST_ERR_EXITING;
-               goto end;
+               goto error;
        }
 
        ops = objd_ops(lum->handle);
        if (!ops) {
                ret = -ENOENT;
-               goto end;
+               goto error;
        }
 
        switch (lum->cmd) {
@@ -643,12 +662,12 @@ int handle_message(struct sock_info *sock_info,
                                }
                                ret = len;
                                free(bytecode);
-                               goto end;
+                               goto error;
                        } else {
                                DBG("incorrect filter data message size: %zd", len);
                                ret = -EINVAL;
                                free(bytecode);
-                               goto end;
+                               goto error;
                        }
                }
                bytecode->bc.len = lum->u.filter.data_size;
@@ -708,12 +727,12 @@ int handle_message(struct sock_info *sock_info,
                                }
                                ret = len;
                                free(node);
-                               goto end;
+                               goto error;
                        } else {
                                DBG("Incorrect exclusion data message size: %zd", len);
                                ret = -EINVAL;
                                free(node);
-                               goto end;
+                               goto error;
                        }
                }
                if (ops->cmd) {
@@ -754,11 +773,11 @@ int handle_message(struct sock_info *sock_info,
                                        goto error;
                                }
                                ret = len;
-                               goto end;
+                               goto error;
                        } else {
                                DBG("incorrect channel data message size: %zd", len);
                                ret = -EINVAL;
-                               goto end;
+                               goto error;
                        }
                }
                args.channel.chan_data = chan_data;
@@ -779,7 +798,7 @@ int handle_message(struct sock_info *sock_info,
                        &args.stream.shm_fd,
                        &args.stream.wakeup_fd);
                if (ret) {
-                       goto end;
+                       goto error;
                }
                if (ops->cmd)
                        ret = ops->cmd(lum->handle, lum->cmd,
@@ -789,6 +808,64 @@ int handle_message(struct sock_info *sock_info,
                        ret = -ENOSYS;
                break;
        }
+       case LTTNG_UST_CONTEXT:
+               switch (lum->u.context.ctx) {
+               case LTTNG_UST_CONTEXT_APP_CONTEXT:
+               {
+                       char *p;
+                       size_t ctxlen, recvlen;
+
+                       ctxlen = strlen("$app.") + lum->u.context.u.app_ctx.provider_name_len - 1
+                                       + strlen(":") + lum->u.context.u.app_ctx.ctx_name_len;
+                       if (ctxlen >= LTTNG_UST_SYM_NAME_LEN) {
+                               ERR("Application context string length size is too large: %zu bytes",
+                                       ctxlen);
+                               ret = -EINVAL;
+                               goto error;
+                       }
+                       strcpy(ctxstr, "$app.");
+                       p = &ctxstr[strlen("$app.")];
+                       recvlen = ctxlen - strlen("$app.");
+                       len = ustcomm_recv_unix_sock(sock, p, recvlen);
+                       switch (len) {
+                       case 0: /* orderly shutdown */
+                               ret = 0;
+                               goto error;
+                       default:
+                               if (len == recvlen) {
+                                       DBG("app context data received");
+                                       break;
+                               } else if (len < 0) {
+                                       DBG("Receive failed from lttng-sessiond with errno %d", (int) -len);
+                                       if (len == -ECONNRESET) {
+                                               ERR("%s remote end closed connection", sock_info->name);
+                                               ret = len;
+                                               goto error;
+                                       }
+                                       ret = len;
+                                       goto error;
+                               } else {
+                                       DBG("incorrect app context data message size: %zd", len);
+                                       ret = -EINVAL;
+                                       goto error;
+                               }
+                       }
+                       /* Put : between provider and ctxname. */
+                       p[lum->u.context.u.app_ctx.provider_name_len - 1] = ':';
+                       args.app_context.ctxname = ctxstr;
+                       break;
+               }
+               default:
+                       break;
+               }
+               if (ops->cmd) {
+                       ret = ops->cmd(lum->handle, lum->cmd,
+                                       (unsigned long) &lum->u,
+                                       &args, sock_info);
+               } else {
+                       ret = -ENOSYS;
+               }
+               break;
        default:
                if (ops->cmd)
                        ret = ops->cmd(lum->handle, lum->cmd,
@@ -799,7 +876,6 @@ int handle_message(struct sock_info *sock_info,
                break;
        }
 
-end:
        lur.handle = lum->handle;
        lur.cmd = lum->cmd;
        lur.ret_val = ret;
@@ -931,7 +1007,12 @@ void cleanup_sock_info(struct sock_info *sock_info, int exiting)
                long page_size;
 
                page_size = sysconf(_SC_PAGE_SIZE);
-               if (page_size > 0) {
+               if (page_size <= 0) {
+                       if (!page_size) {
+                               errno = EINVAL;
+                       }
+                       PERROR("Error in sysconf(_SC_PAGE_SIZE)");
+               } else {
                        ret = munmap(sock_info->wait_shm_mmap, page_size);
                        if (ret) {
                                ERR("Error unmapping wait shm");
@@ -1113,7 +1194,11 @@ char *get_map_shm(struct sock_info *sock_info)
        char *wait_shm_mmap;
 
        page_size = sysconf(_SC_PAGE_SIZE);
-       if (page_size < 0) {
+       if (page_size <= 0) {
+               if (!page_size) {
+                       errno = EINVAL;
+               }
+               PERROR("Error in sysconf(_SC_PAGE_SIZE)");
                goto error;
        }
 
@@ -1220,8 +1305,9 @@ restart:
                         * deals with a killed or broken session daemon.
                         */
                        sleep(5);
+               } else {
+                       has_waited = 1;
                }
-               has_waited = 1;
                prev_connect_failed = 0;
        }
 
@@ -1400,7 +1486,13 @@ restart:
                        print_cmd(lum.cmd, lum.handle);
                        ret = handle_message(sock_info, sock, &lum);
                        if (ret) {
-                               ERR("Error handling message for %s socket", sock_info->name);
+                               ERR("Error handling message for %s socket",
+                                       sock_info->name);
+                               /*
+                                * Close socket if protocol error is
+                                * detected.
+                                */
+                               goto end;
                        }
                        continue;
                default:
@@ -1487,7 +1579,6 @@ void __attribute__((constructor)) lttng_ust_init(void)
        lttng_ring_buffer_client_discard_init();
        lttng_ring_buffer_client_discard_rt_init();
        lttng_perf_counter_init();
-       lttng_context_init();
        /*
         * Invoke ust malloc wrapper init before starting other threads.
         */
@@ -1592,7 +1683,6 @@ void lttng_ust_cleanup(int exiting)
         */
        lttng_ust_abi_exit();
        lttng_ust_events_exit();
-       lttng_context_exit();
        lttng_perf_counter_exit();
        lttng_ring_buffer_client_discard_rt_exit();
        lttng_ring_buffer_client_discard_exit();