From: "Steven Rostedt (VMware)" <rostedt@xxxxxxxxxxx>
If a trace event wraps the special __entry variable to dereference it with
parenthesis, it shows up in the trace event format file wrapping the
"(REC)" as well. For example, the "func_repeats" event passed the __entry
into a helper macro in the TP_printk() portion, and the macro correctly
wrapped its parameter in parenthesis. This caused the output to show:
"(((u64)(REC)->top_delta_ts << 32) | (REC)->bottom_delta_ts)"
The parser then failed to parse the "(REC)->" portion, as it expected the
"->" to appear directly after the "REC". This is not a requirement, and
the parser should be able to handle such cases.
Fixes: 6582b0a ("tools/events: Add files to create libtraceevent.a")
Reported-by: Julia Lawall <julia.lawall@xxxxxxxx>
Signed-off-by: Steven Rostedt (VMware) <rostedt@xxxxxxxxxxx>
---
src/event-parse.c | 27 ++++++++++++++++++++++++---
1 file changed, 24 insertions(+), 3 deletions(-)
diff --git a/src/event-parse.c b/src/event-parse.c
index 97c1a97..1217491 100644
--- a/src/event-parse.c
+++ b/src/event-parse.c
@@ -2311,8 +2311,19 @@ process_entry(struct tep_event *event __maybe_unused, struct tep_print_arg *arg,
char *field;
char *token;
- if (read_expected(TEP_EVENT_OP, "->") < 0)
- goto out_err;
+ type = read_token_item(&token);
+ /*
+ * Check if REC happens to be surrounded by parenthesis, and
+ * return if that's the case, as "(REC)->" is valid.
+ * but return TEP_EVENT_ITEM.
+ */
+ if (type == TEP_EVENT_DELIM && strcmp(token, ")") == 0) {
+ *tok = token;
+ return TEP_EVENT_ITEM;
+ }
+
+ if (test_type_token(type, token, TEP_EVENT_OP, "->"))
+ goto out_free;
if (read_expect_type(TEP_EVENT_ITEM, &token) < 0)
goto out_free;
@@ -2338,7 +2349,6 @@ process_entry(struct tep_event *event __maybe_unused, struct tep_print_arg *arg,
out_free:
free_token(token);
- out_err:
*tok = NULL;
return TEP_EVENT_ERROR;
}
@@ -3033,6 +3043,17 @@ process_paren(struct tep_event *event, struct tep_print_arg *arg, char **tok)
if (type == TEP_EVENT_ERROR)
goto out_free;
+ /*
+ * If REC is surrounded by parenthesis, the process_arg()
+ * will return TEP_EVENT_ITEM with token == ")". In
+ * this case, we need to continue processing the item
+ * and return.
+ */
+ if (type == TEP_EVENT_ITEM && strcmp(token, ")") == 0) {
+ free_token(token);
+ return process_entry(event, arg, tok);
+ }
+
if (test_type_token(type, token, TEP_EVENT_DELIM, ")"))
goto out_free;
--
2.29.2
|