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From: Steven Rostedt <rostedt@goodmis.org>
To: linux-trace-devel@vger.kernel.org
Cc: "Steven Rostedt (VMware)" <rostedt@goodmis.org>
Subject: [PATCH 1/4] libtracefs: Implement tracefs_list_size()
Date: Tue,  6 Jul 2021 23:11:07 -0400	[thread overview]
Message-ID: <20210707031110.249759-2-rostedt@goodmis.org> (raw)
In-Reply-To: <20210707031110.249759-1-rostedt@goodmis.org>

From: "Steven Rostedt (VMware)" <rostedt@goodmis.org>

Add tracefs_list_size() that returns a the size of a list created by
tracefs_list_add().

Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
---
 include/tracefs.h   |  1 +
 src/tracefs-utils.c | 16 ++++++++++++++++
 2 files changed, 17 insertions(+)

diff --git a/include/tracefs.h b/include/tracefs.h
index 266c513e4116..6b9a76c4c40a 100644
--- a/include/tracefs.h
+++ b/include/tracefs.h
@@ -65,6 +65,7 @@ int tracefs_error_clear(struct tracefs_instance *instance);
 
 void tracefs_list_free(char **list);
 char **tracefs_list_add(char **list, const char *string);
+int tracefs_list_size(char **list);
 
 /**
  * tracefs_trace_on_get_fd - Get a file descriptor of "tracing_on" in given instance
diff --git a/src/tracefs-utils.c b/src/tracefs-utils.c
index ec5ecb08ed2e..6750336c9ef6 100644
--- a/src/tracefs-utils.c
+++ b/src/tracefs-utils.c
@@ -447,3 +447,19 @@ char **tracefs_list_add(char **list, const char *string)
 
 	return list;
 }
+
+/**
+ * tracefs_list_size - Return the number of strings in the list
+ * @list: The list to determine the size.
+ *
+ * Returns the number of elements in the list.
+ * If @list is NULL, then zero is returned.
+ */
+int tracefs_list_size(char **list)
+{
+	if (!list)
+		return 0;
+
+	list--;
+	return (int)*(unsigned long *)list;
+}
-- 
2.30.2


  reply	other threads:[~2021-07-07  3:11 UTC|newest]

Thread overview: 9+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2021-07-07  3:11 [PATCH 0/4] libtracefs: Work to add histogram APIs Steven Rostedt
2021-07-07  3:11 ` Steven Rostedt [this message]
2021-07-07  3:11 ` [PATCH 2/4] libtracefs: Implement functions to work on event directory files Steven Rostedt
2021-07-07  3:11 ` [PATCH 3/4] libtracefs: Have instances have internal ref counting Steven Rostedt
2021-07-07  3:11 ` [PATCH 4/4] libtracefs: Implement API to create / modify and display histograms Steven Rostedt
2021-07-07  8:12   ` Yordan Karadzhov (VMware)
2021-07-07 13:13     ` Steven Rostedt
2021-07-07 13:21       ` Yordan Karadzhov (VMware)
2021-07-07 13:48         ` Steven Rostedt

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