From db8a5c0eb2d4b986b9505e4dfc3c6c72f39b2f13 Mon Sep 17 00:00:00 2001
From: Dan Carpenter <dan.carpenter@oracle.com>
Date: Wed, 6 Feb 2013 21:53:53 +0300
Subject: [PATCH] param_(filter|limit|set): add some comments

Hopefully, this clarifies a little how these work together.

Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
---
 smatch_param_filter.c | 14 ++++++++++++++
 smatch_param_limit.c  | 19 +++++++++++++++++++
 smatch_param_set.c    | 17 +++++++++++++++++
 3 files changed, 50 insertions(+)

diff --git a/smatch_param_filter.c b/smatch_param_filter.c
index d86d0cc5..192d29f9 100644
--- a/smatch_param_filter.c
+++ b/smatch_param_filter.c
@@ -7,6 +7,20 @@
  *
  */
 
+/*
+ * This is for functions like:
+ *
+ * void foo(int *x)
+ * {
+ * 	if (*x == 42)
+ *		*x = 0;
+ * }
+ *
+ * The final value of *x depends on the input to the function but with *x == 42
+ * filtered out.
+ *
+ */
+
 #include "smatch.h"
 #include "smatch_extra.h"
 #include "smatch_slist.h"
diff --git a/smatch_param_limit.c b/smatch_param_limit.c
index 148a9b6b..62a49d11 100644
--- a/smatch_param_limit.c
+++ b/smatch_param_limit.c
@@ -7,6 +7,25 @@
  *
  */
 
+/*
+ * This is for functions like this:
+ *
+ * int foo(int a)
+ * {
+ *        if (a >= 0 && a < 10) {
+ *                 a = 42;
+ *                 return 1;
+ *        }
+ *        return 0;
+ * }
+ *
+ * If we pass in 5, it returns 1.
+ *
+ * It's a bit complicated because we can't just consider the final value, we
+ * have to always consider the passed in value.
+ *
+ */
+
 #include "scope.h"
 #include "smatch.h"
 #include "smatch_extra.h"
diff --git a/smatch_param_set.c b/smatch_param_set.c
index 7bbc8d5c..dd215eb0 100644
--- a/smatch_param_set.c
+++ b/smatch_param_set.c
@@ -7,6 +7,23 @@
  *
  */
 
+/*
+ * This is for functions like:
+ *
+ * int foo(int *x)
+ * {
+ * 	if (*x == 42) {
+ *		*x = 0;
+ *		return 1;
+ *	}
+ * 	return 0;
+ * }
+ *
+ * If we return 1 that means the value of *x has been set to 0.  If we return
+ * 0 then we have left *x alone.
+ *
+ */
+
 #include "scope.h"
 #include "smatch.h"
 #include "smatch_slist.h"
-- 
2.11.4.GIT