corrected sidtab locking patch

[Jason Tang <jtang@tresys.com>]

[-- Attachment #1: Type: text/plain, Size: 327 bytes --]

The following patch allows a program to enable locking in
libsepol/sidtab.c.  By default sidtab.c does not lock the sidtab when
adding and removing entries; this causes problems for multi-threaded
programs using it.  Programs may set up function pointers to perform
locking as they see fit.


-- 
Jason Tang / jtang@tresys.com

[-- Attachment #2: patch-locking --]
[-- Type: text/x-patch, Size: 1812 bytes --]

diff -purN nsa/selinux-usr/libsepol/include/sepol/sidtab.h nsa-selinux-usr/libsepol/include/sepol/sidtab.h
--- nsa/selinux-usr/libsepol/include/sepol/sidtab.h	2005-07-13 15:42:37.000000000 -0400
+++ nsa-selinux-usr/libsepol/include/sepol/sidtab.h	2005-08-24 17:40:19.000000000 -0400
@@ -72,6 +72,11 @@ extern void sepol_sidtab_set(sidtab_t *d
 
 extern void sepol_sidtab_shutdown(sidtab_t *s);
 
+typedef void (* sepol_sidtab_lock_func)(sidtab_t *);
+extern void sepol_sidtab_set_init_func(sepol_sidtab_lock_func func);
+extern void sepol_sidtab_set_lock_func(sepol_sidtab_lock_func func);
+extern void sepol_sidtab_set_unlock_func(sepol_sidtab_lock_func func);
+
 #endif	/* _SIDTAB_H_ */
 
 /* FLASK */
diff -purN nsa/selinux-usr/libsepol/src/sidtab.c nsa-selinux-usr/libsepol/src/sidtab.c
--- nsa/selinux-usr/libsepol/src/sidtab.c	2005-05-13 15:53:31.000000000 -0400
+++ nsa-selinux-usr/libsepol/src/sidtab.c	2005-08-24 17:28:06.000000000 -0400
@@ -23,6 +23,14 @@
 #define SIDTAB_LOCK(s) 
 #define SIDTAB_UNLOCK(s)
 
+static void do_no_lock_func(sidtab_t *s __attribute__((unused))) {
+        /* as the name suggests, this function does not do anything */
+}
+
+static sepol_sidtab_lock_func INIT_SIDTAB_LOCK = do_no_lock_func;
+static sepol_sidtab_lock_func SIDTAB_LOCK = do_no_lock_func;
+static sepol_sidtab_lock_func SIDTAB_UNLOCK = do_no_lock_func;
+
 int sepol_sidtab_init(sidtab_t *s) 
 {
 	int i;
@@ -334,5 +342,17 @@ void sepol_sidtab_shutdown(sidtab_t *s)
 	SIDTAB_UNLOCK(s);
 }
 
+void sepol_sidtab_set_init_func(sepol_sidtab_lock_func func) {
+        INIT_SIDTAB_LOCK = func;
+}
+
+void sepol_sidtab_set_lock_func(sepol_sidtab_lock_func func) {
+        SIDTAB_LOCK = func;
+}
+
+void sepol_sidtab_set_unlock_func(sepol_sidtab_lock_func func) {
+        SIDTAB_UNLOCK = func;
+}
+
 /* FLASK */