From: Jérémie Galarneau <jeremie.galarneau@efficios.com>
Date: Thu, 25 Aug 2016 20:43:13 +0000 (-0400)
Subject: Clean-up snapshot command error reporting
X-Git-Tag: v2.9.0-rc1~54
X-Git-Url: https://git.lttng.org./?a=commitdiff_plain;h=903ef6855b15a3352dee0d9870ca1b918669aa80;p=lttng-tools.git

Clean-up snapshot command error reporting

Signed-off-by: Jérémie Galarneau <jeremie.galarneau@efficios.com>
---

diff --git a/include/lttng/lttng-error.h b/include/lttng/lttng-error.h
index df59f8f7b..db6fe73c2 100644
--- a/include/lttng/lttng-error.h
+++ b/include/lttng/lttng-error.h
@@ -143,7 +143,8 @@ enum lttng_error_code {
 	LTTNG_ERR_PER_PID_SESSION        = 120, /* Per-PID sessions unsupported */
 	LTTNG_ERR_KERN_CONTEXT_UNAVAILABLE = 121, /* Context unavailable on this kernel */
 	LTTNG_ERR_REGEN_STATEDUMP_FAIL   = 122, /* Failed to regenerate the state dump */
-	LTTNG_ERR_REGEN_STATEDUMP_NOMEM   = 123, /* Failed to regenerate the state dump, not enough memory */
+	LTTNG_ERR_REGEN_STATEDUMP_NOMEM  = 123, /* Failed to regenerate the state dump, not enough memory */
+	LTTNG_ERR_NOT_SNAPSHOT_SESSION   = 124, /* Session is not in snapshot mode. */
 
 	/* MUST be last element */
 	LTTNG_ERR_NR,                           /* Last element */
diff --git a/src/bin/lttng-sessiond/cmd.c b/src/bin/lttng-sessiond/cmd.c
index 86c3c765c..916a73be2 100644
--- a/src/bin/lttng-sessiond/cmd.c
+++ b/src/bin/lttng-sessiond/cmd.c
@@ -3207,11 +3207,10 @@ int cmd_snapshot_add_output(struct ltt_session *session,
 	DBG("Cmd snapshot add output for session %s", session->name);
 
 	/*
-	 * Permission denied to create an output if the session is not
-	 * set in no output mode.
+	 * Can't create an output if the session is not set in no-output mode.
 	 */
 	if (session->output_traces) {
-		ret = LTTNG_ERR_EPERM;
+		ret = LTTNG_ERR_NOT_SNAPSHOT_SESSION;
 		goto error;
 	}
 
@@ -3275,7 +3274,7 @@ int cmd_snapshot_del_output(struct ltt_session *session,
 	 * set in no output mode.
 	 */
 	if (session->output_traces) {
-		ret = LTTNG_ERR_EPERM;
+		ret = LTTNG_ERR_NOT_SNAPSHOT_SESSION;
 		goto error;
 	}
 
@@ -3327,19 +3326,19 @@ ssize_t cmd_snapshot_list_outputs(struct ltt_session *session,
 	 * set in no output mode.
 	 */
 	if (session->output_traces) {
-		ret = -LTTNG_ERR_EPERM;
-		goto error;
+		ret = -LTTNG_ERR_NOT_SNAPSHOT_SESSION;
+		goto end;
 	}
 
 	if (session->snapshot.nb_output == 0) {
 		ret = 0;
-		goto error;
+		goto end;
 	}
 
 	list = zmalloc(session->snapshot.nb_output * sizeof(*list));
 	if (!list) {
 		ret = -LTTNG_ERR_NOMEM;
-		goto error;
+		goto end;
 	}
 
 	/* Copy list from session to the new list object. */
@@ -3352,14 +3351,14 @@ ssize_t cmd_snapshot_list_outputs(struct ltt_session *session,
 		if (lttng_strncpy(list[idx].name, output->name,
 				sizeof(list[idx].name))) {
 			ret = -LTTNG_ERR_INVALID;
-			goto error_unlock;
+			goto error;
 		}
 		if (output->consumer->type == CONSUMER_DST_LOCAL) {
 			if (lttng_strncpy(list[idx].ctrl_url,
 					output->consumer->dst.trace_path,
 					sizeof(list[idx].ctrl_url))) {
 				ret = -LTTNG_ERR_INVALID;
-				goto error_unlock;
+				goto error;
 			}
 		} else {
 			/* Control URI. */
@@ -3367,7 +3366,7 @@ ssize_t cmd_snapshot_list_outputs(struct ltt_session *session,
 					list[idx].ctrl_url, sizeof(list[idx].ctrl_url));
 			if (ret < 0) {
 				ret = -LTTNG_ERR_NOMEM;
-				goto error_unlock;
+				goto error;
 			}
 
 			/* Data URI. */
@@ -3375,7 +3374,7 @@ ssize_t cmd_snapshot_list_outputs(struct ltt_session *session,
 					list[idx].data_url, sizeof(list[idx].data_url));
 			if (ret < 0) {
 				ret = -LTTNG_ERR_NOMEM;
-				goto error_unlock;
+				goto error;
 			}
 		}
 		idx++;
@@ -3384,10 +3383,10 @@ ssize_t cmd_snapshot_list_outputs(struct ltt_session *session,
 	*outputs = list;
 	list = NULL;
 	ret = session->snapshot.nb_output;
-error_unlock:
-	rcu_read_unlock();
 error:
+	rcu_read_unlock();
 	free(list);
+end:
 	return ret;
 }
 
@@ -3861,7 +3860,7 @@ int cmd_snapshot_record(struct ltt_session *session,
 	 * set in no output mode.
 	 */
 	if (session->output_traces) {
-		ret = LTTNG_ERR_EPERM;
+		ret = LTTNG_ERR_NOT_SNAPSHOT_SESSION;
 		goto error;
 	}
 
diff --git a/src/bin/lttng/commands/snapshot.c b/src/bin/lttng/commands/snapshot.c
index 00aa5b790..11cc2496a 100644
--- a/src/bin/lttng/commands/snapshot.c
+++ b/src/bin/lttng/commands/snapshot.c
@@ -579,9 +579,6 @@ int cmd_snapshot(int argc, const char **argv)
 	command_ret = handle_command(poptGetArgs(pc));
 	if (command_ret) {
 		switch (-command_ret) {
-		case LTTNG_ERR_EPERM:
-			ERR("The session needs to be set in no output mode (--no-output)");
-			break;
 		case LTTNG_ERR_SNAPSHOT_NODATA:
 			WARN("%s", lttng_strerror(command_ret));
 
diff --git a/src/common/error.c b/src/common/error.c
index 1067e4852..938932cdc 100644
--- a/src/common/error.c
+++ b/src/common/error.c
@@ -185,6 +185,7 @@ static const char *error_string_array[] = {
 	[ ERROR_INDEX(LTTNG_ERR_KERN_CONTEXT_UNAVAILABLE) ] = "Context unavailable on this kernel",
 	[ ERROR_INDEX(LTTNG_ERR_REGEN_STATEDUMP_FAIL) ] = "Failed to regenerate the state dump",
 	[ ERROR_INDEX(LTTNG_ERR_REGEN_STATEDUMP_NOMEM) ] = "Failed to regenerate the state dump, not enough memory",
+	[ ERROR_INDEX(LTTNG_ERR_NOT_SNAPSHOT_SESSION) ] = "Snapshot command can't be applied to a non-snapshot session",
 
 	/* Last element */
 	[ ERROR_INDEX(LTTNG_ERR_NR) ] = "Unknown error code"