From 3dcb34ab38a7f980f2b148c978dcadf7a6643cc0 Mon Sep 17 00:00:00 2001 From: Mathieu Desnoyers Date: Thu, 14 Apr 2022 15:56:14 -0400 Subject: [PATCH] Cleanup: combine duplicated communication error handling Signed-off-by: Mathieu Desnoyers Change-Id: I225fe8581e0552d097d740b1272502903302002c --- src/lib/lttng-ust/lttng-ust-comm.c | 324 +++++++++-------------------- 1 file changed, 95 insertions(+), 229 deletions(-) diff --git a/src/lib/lttng-ust/lttng-ust-comm.c b/src/lib/lttng-ust/lttng-ust-comm.c index 69ff7e5e..c3325556 100644 --- a/src/lib/lttng-ust/lttng-ust-comm.c +++ b/src/lib/lttng-ust/lttng-ust-comm.c @@ -893,14 +893,53 @@ const char *bytecode_type_str(uint32_t cmd) { switch (cmd) { case LTTNG_UST_ABI_CAPTURE: - return "capture"; + return "capture bytecode"; case LTTNG_UST_ABI_FILTER: - return "filter"; + return "filter bytecode"; default: abort(); } } +enum handle_message_error { + MSG_OK = 0, + MSG_ERROR = 1, + MSG_SHUTDOWN = 2, +}; + +/* + * Return: + * < 0: error + * 0: OK, handle command. + * > 0: shutdown (no error). + */ +static +enum handle_message_error handle_error(struct sock_info *sock_info, ssize_t len, + ssize_t expected_len, const char *str, int *error_code) +{ + if (!len) { + /* orderly shutdown */ + *error_code = 0; + return MSG_SHUTDOWN; + } + if (len == expected_len) { + DBG("%s data received", str); + *error_code = 0; + return MSG_OK; + } + 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); + } + *error_code = len; + return MSG_ERROR; + } + DBG("incorrect %s data message size: %zd", str, len); + *error_code = -EINVAL; + return MSG_ERROR; +} + static int handle_bytecode_recv(struct sock_info *sock_info, int sock, struct ustcomm_ust_msg *lum) @@ -933,14 +972,14 @@ int handle_bytecode_recv(struct sock_info *sock_info, } if (data_size > data_size_max) { - ERR("Bytecode %s data size is too large: %u bytes", + ERR("%s data size is too large: %u bytes", bytecode_type_str(lum->cmd), data_size); ret = -EINVAL; goto end; } if (reloc_offset > data_size) { - ERR("Bytecode %s reloc offset %u is not within data", + ERR("%s reloc offset %u is not within data", bytecode_type_str(lum->cmd), reloc_offset); ret = -EINVAL; goto end; @@ -959,34 +998,13 @@ int handle_bytecode_recv(struct sock_info *sock_info, bytecode->type = type; len = ustcomm_recv_unix_sock(sock, bytecode->bc.data, bytecode->bc.len); - switch (len) { - case 0: /* orderly shutdown */ - ret = 0; + switch (handle_error(sock_info, len, bytecode->bc.len, bytecode_type_str(lum->cmd), &ret)) { + case MSG_OK: + break; + case MSG_ERROR: /* Fallthrough */ + case MSG_SHUTDOWN: goto end; - default: - if (len == bytecode->bc.len) { - DBG("Bytecode %s data received", - bytecode_type_str(lum->cmd)); - 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 end; - } - ret = len; - goto end; - } else { - DBG("Incorrect %s bytecode data message size: %zd", - bytecode_type_str(lum->cmd), len); - ret = -EINVAL; - goto end; - } } - ops = lttng_ust_abi_objd_ops(lum->handle); if (!ops) { ret = -ENOENT; @@ -1054,14 +1072,12 @@ int handle_message(struct sock_info *sock_info, { int ret = 0; const struct lttng_ust_abi_objd_ops *ops; - struct ustcomm_ust_reply lur; + struct ustcomm_ust_reply lur = {}; union lttng_ust_abi_args args; char ctxstr[LTTNG_UST_ABI_SYM_NAME_LEN]; /* App context string. */ ssize_t len; void *var_len_cmd_data = NULL; - memset(&lur, 0, sizeof(lur)); - if (ust_lock()) { ret = -LTTNG_UST_ERR_EXITING; goto error; @@ -1160,32 +1176,13 @@ int handle_message(struct sock_info *sock_info, node->excluder.count = count; len = ustcomm_recv_unix_sock(sock, node->excluder.names, count * LTTNG_UST_ABI_SYM_NAME_LEN); - switch (len) { - case 0: /* orderly shutdown */ - ret = 0; + switch (handle_error(sock_info, len, count * LTTNG_UST_ABI_SYM_NAME_LEN, "exclusion", &ret)) { + case MSG_OK: + break; + case MSG_ERROR: /* Fallthrough */ + case MSG_SHUTDOWN: free(node); goto error; - default: - if (len == count * LTTNG_UST_ABI_SYM_NAME_LEN) { - DBG("Exclusion 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; - free(node); - goto error; - } - ret = len; - free(node); - goto error; - } else { - DBG("Incorrect exclusion data message size: %zd", len); - ret = -EINVAL; - free(node); - goto error; - } } if (ops->cmd) ret = ops->cmd(lum->handle, lum->cmd, @@ -1202,33 +1199,14 @@ int handle_message(struct sock_info *sock_info, len = ustcomm_recv_event_notifier_notif_fd_from_sessiond(sock, &event_notifier_notif_fd); - switch (len) { - case 0: /* orderly shutdown */ - ret = 0; - goto error; - case 1: + switch (handle_error(sock_info, len, 1, "event notifier group", &ret)) { + case MSG_OK: break; - default: - 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 event notifier fd message size: %zd", - len); - ret = -EINVAL; - goto error; - } + case MSG_ERROR: /* Fallthrough */ + case MSG_SHUTDOWN: + goto error; } - args.event_notifier_handle.event_notifier_notif_fd = - event_notifier_notif_fd; + args.event_notifier_handle.event_notifier_notif_fd = event_notifier_notif_fd; if (ops->cmd) ret = ops->cmd(lum->handle, lum->cmd, (unsigned long) &lum->u, @@ -1252,28 +1230,12 @@ int handle_message(struct sock_info *sock_info, len = ustcomm_recv_channel_from_sessiond(sock, &chan_data, lum->u.channel.len, &wakeup_fd); - switch (len) { - case 0: /* orderly shutdown */ - ret = 0; + switch (handle_error(sock_info, len, lum->u.channel.len, "channel", &ret)) { + case MSG_OK: + break; + case MSG_ERROR: /* Fallthrough */ + case MSG_SHUTDOWN: goto error; - default: - if (len == lum->u.channel.len) { - DBG("channel 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 channel data message size: %zd", len); - ret = -EINVAL; - goto error; - } } args.channel.chan_data = chan_data; args.channel.wakeup_fd = wakeup_fd; @@ -1352,28 +1314,12 @@ int handle_message(struct sock_info *sock_info, p = &ctxstr[strlen("$app.")]; recvlen = ctxlen - strlen("$app."); len = ustcomm_recv_unix_sock(sock, p, recvlen); - switch (len) { - case 0: /* orderly shutdown */ - ret = 0; + switch (handle_error(sock_info, len, recvlen, "app context", &ret)) { + case MSG_OK: + break; + case MSG_ERROR: /* Fallthrough */ + case MSG_SHUTDOWN: 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] = ':'; @@ -1395,28 +1341,12 @@ int handle_message(struct sock_info *sock_info, { len = ustcomm_recv_var_len_cmd_from_sessiond(sock, &var_len_cmd_data, lum->u.var_len_cmd.cmd_len); - switch (len) { - case 0: /* orderly shutdown */ - ret = 0; + switch (handle_error(sock_info, len, lum->u.var_len_cmd.cmd_len, "counter", &ret)) { + case MSG_OK: + break; + case MSG_ERROR: /* Fallthrough */ + case MSG_SHUTDOWN: goto error; - default: - if (len == lum->u.var_len_cmd.cmd_len) { - DBG("counter 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 counter data message size: %zd", len); - ret = -EINVAL; - goto error; - } } args.counter.len = lum->u.var_len_cmd.cmd_len; if (ops->cmd) @@ -1431,28 +1361,12 @@ int handle_message(struct sock_info *sock_info, { len = ustcomm_recv_var_len_cmd_from_sessiond(sock, &var_len_cmd_data, lum->u.var_len_cmd.cmd_len); - switch (len) { - case 0: /* orderly shutdown */ - ret = 0; + switch (handle_error(sock_info, len, lum->u.var_len_cmd.cmd_len, "counter global", &ret)) { + case MSG_OK: + break; + case MSG_ERROR: /* Fallthrough */ + case MSG_SHUTDOWN: goto error; - default: - if (len == lum->u.var_len_cmd.cmd_len) { - DBG("counter 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 counter data message size: %zd", len); - ret = -EINVAL; - goto error; - } } /* Receive shm_fd */ ret = ustcomm_recv_counter_shm_from_sessiond(sock, &args.counter_shm.shm_fd); @@ -1482,28 +1396,12 @@ int handle_message(struct sock_info *sock_info, { len = ustcomm_recv_var_len_cmd_from_sessiond(sock, &var_len_cmd_data, lum->u.var_len_cmd.cmd_len); - switch (len) { - case 0: /* orderly shutdown */ - ret = 0; + switch (handle_error(sock_info, len, lum->u.var_len_cmd.cmd_len, "counter cpu", &ret)) { + case MSG_OK: + break; + case MSG_ERROR: /* Fallthrough */ + case MSG_SHUTDOWN: goto error; - default: - if (len == lum->u.var_len_cmd.cmd_len) { - DBG("counter 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 counter data message size: %zd", len); - ret = -EINVAL; - goto error; - } } /* Receive shm_fd */ ret = ustcomm_recv_counter_shm_from_sessiond(sock, &args.counter_shm.shm_fd); @@ -1533,28 +1431,12 @@ int handle_message(struct sock_info *sock_info, { len = ustcomm_recv_var_len_cmd_from_sessiond(sock, &var_len_cmd_data, lum->u.var_len_cmd.cmd_len); - switch (len) { - case 0: /* orderly shutdown */ - ret = 0; + switch (handle_error(sock_info, len, lum->u.var_len_cmd.cmd_len, "counter event", &ret)) { + case MSG_OK: + break; + case MSG_ERROR: /* Fallthrough */ + case MSG_SHUTDOWN: goto error; - default: - if (len == lum->u.var_len_cmd.cmd_len) { - DBG("counter event 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 counter data message size: %zd", len); - ret = -EINVAL; - goto error; - } } args.counter_event.len = lum->u.var_len_cmd.cmd_len; if (ops->cmd) @@ -1569,28 +1451,12 @@ int handle_message(struct sock_info *sock_info, { len = ustcomm_recv_var_len_cmd_from_sessiond(sock, &var_len_cmd_data, lum->u.var_len_cmd.cmd_len); - switch (len) { - case 0: /* orderly shutdown */ - ret = 0; + switch (handle_error(sock_info, len, lum->u.var_len_cmd.cmd_len, "event notifier", &ret)) { + case MSG_OK: + break; + case MSG_ERROR: /* Fallthrough */ + case MSG_SHUTDOWN: goto error; - default: - if (len == lum->u.var_len_cmd.cmd_len) { - DBG("event notifier 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 event notifier data message size: %zd", len); - ret = -EINVAL; - goto error; - } } args.event_notifier.len = lum->u.var_len_cmd.cmd_len; if (ops->cmd) -- 2.34.1