From: Dan Carpenter <dan.carpenter@oracle.com>
Date: Wed, 18 Dec 2013 15:19:55 +0000 (+0300)
Subject: *new* add smatch_data/kernel.silenced_functions to silence common noise
X-Git-Tag: 1.60~463
X-Git-Url: https://repo.or.cz/w/smatch.git/commitdiff_plain/03a339c45723793788e5ec152b215b5f0dfa0ab5

*new* add smatch_data/kernel.silenced_functions to silence common noise

There are some very common functions which generate warnings.  It's a bit
tricky to fix smatch to handle them properly so I've just added file to
silence them in an unsubtle way.

Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
---

diff --git a/smatch.h b/smatch.h
index 012d0644..9c1333fd 100644
--- a/smatch.h
+++ b/smatch.h
@@ -163,6 +163,8 @@ extern int final_pass;
 extern struct symbol *cur_func_sym;
 extern int option_debug;
 extern int local_debug;
+extern int option_info;
+int is_silenced_function(void);
 
 extern FILE *sm_outfd;
 #define sm_printf(msg...) do { if (final_pass || option_debug) fprintf(sm_outfd, msg); } while (0)
@@ -179,6 +181,8 @@ do {                                                           \
 	print_implied_debug_msg();                             \
 	if (!option_debug && !final_pass)                      \
 		break;                                         \
+	if (!option_info && is_silenced_function())	       \
+		break;					       \
 	sm_prefix();					       \
         sm_printf(msg);                                        \
         sm_printf("\n");                                       \
@@ -608,7 +612,6 @@ extern int option_no_data;
 extern int option_spammy;
 extern int option_full_path;
 extern int option_param_mapper;
-extern int option_info;
 extern int option_call_tree;
 extern int num_checks;
 
diff --git a/smatch_data/kernel.silenced_functions b/smatch_data/kernel.silenced_functions
new file mode 100644
index 00000000..ffa34af5
--- /dev/null
+++ b/smatch_data/kernel.silenced_functions
@@ -0,0 +1,7 @@
+/* Don't print anything from these functions */
+atomic_dec_and_test
+atomic_sub_and_test
+test_and_clear_bit
+test_and_set_bit
+__copy_to_user_nocheck
+__copy_from_user_nocheck
diff --git a/smatch_project.c b/smatch_project.c
index 7b24908b..5b9601b2 100644
--- a/smatch_project.c
+++ b/smatch_project.c
@@ -16,6 +16,23 @@
 
 #include "smatch.h"
 #include "smatch_extra.h"
+#include "smatch_function_hashtable.h"
+
+static DEFINE_HASHTABLE_INSERT(insert_func, char, int);
+static DEFINE_HASHTABLE_SEARCH(search_func, char, int);
+static struct hashtable *silenced_funcs;
+
+int is_silenced_function(void)
+{
+	char *func;
+
+	func = get_function();
+	if (!func)
+		return 0;
+	if (search_func(silenced_funcs, func))
+		return 1;
+	return 0;
+}
 
 static void register_no_return_funcs(void)
 {
@@ -71,8 +88,37 @@ static void register_ignored_macros(void)
 	clear_token_alloc();
 }
 
+static void register_silenced_functions(void)
+{
+	struct token *token;
+	char *func;
+	char name[256];
+
+	silenced_funcs = create_function_hashtable(500);
+
+	if (option_project == PROJ_NONE)
+		return;
+
+	snprintf(name, 256, "%s.silenced_functions", option_project_str);
+
+	token = get_tokens_file(name);
+	if (!token)
+		return;
+	if (token_type(token) != TOKEN_STREAMBEGIN)
+		return;
+	token = token->next;
+	while (token_type(token) != TOKEN_STREAMEND) {
+		if (token_type(token) != TOKEN_IDENT)
+			return;
+		func = alloc_string(show_ident(token->ident));
+		insert_func(silenced_funcs, func, INT_PTR(1));
+		token = token->next;
+	}
+	clear_token_alloc();
+}
 void register_project(int id)
 {
 	register_no_return_funcs();
 	register_ignored_macros();
+	register_silenced_functions();
 }