tracing/filters: Add comment for match callbacks

We should be clear on 2 things: - the length parameter of a match callback includes tailing '\0'. - the string to be searched might not be NULL-terminated. Signed-off-by: Li Zefan <lizf@cn.fujitsu.com> LKML-Reference: <4B4E8770.7000608@cn.fujitsu.com> Signed-off-by: Steven Rostedt <rostedt@goodmis.org>

tracing/filters: Add comment for match callbacks
We should be clear on 2 things: - the length parameter of a match callback includes tailing '\0'. - the string to be searched might not be NULL-terminated. Signed-off-by: Li Zefan <lizf@cn.fujitsu.com> LKML-Reference: <4B4E8770.7000608@cn.fujitsu.com> Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
Li Zefan · Steven Rostedt
1 parent 16da27a8bc
Showing 1 changed file with 12 additions and 1 deletions Side-by-side Diff
kernel/trace/trace_events_filter.c
@@ -252,7 +252,18 @@
 	return 0;
 }
  
-/* Basic regex callbacks */
+/*
+ * regex_match_foo - Basic regex callbacks
+ *
+ * @str: the string to be searched
+ * @r:   the regex structure containing the pattern string
+ * @len: the length of the string to be searched (including '\0')
+ *
+ * Note:
+ * - @str might not be NULL-terminated if it's of type DYN_STRING
+ *   or STATIC_STRING
+ */
+
 static int regex_match_full(char *str, struct regex *r, int len)
 {
 	if (strncmp(str, r->pattern, len) == 0)
...	...	@@ -252,7 +252,18 @@
252	252	return 0;
253	253	}
254	254
255		-/* Basic regex callbacks */
	255	+/*
	256	+ * regex_match_foo - Basic regex callbacks
	257	+ *
	258	+ * @str: the string to be searched
	259	+ * @r: the regex structure containing the pattern string
	260	+ * @len: the length of the string to be searched (including '\0')
	261	+ *
	262	+ * Note:
	263	+ * - @str might not be NULL-terminated if it's of type DYN_STRING
	264	+ * or STATIC_STRING
	265	+ */
	266	+
256	267	static int regex_match_full(char str, struct regex r, int len)
257	268	{
258	269	if (strncmp(str, r->pattern, len) == 0)