1 files changed, 129 insertions, 0 deletions
diff --git a/security/nss/lib/ssl/sslmutex.h b/security/nss/lib/ssl/sslmutex.h
new file mode 100644
index 0000000000..f99b4d0242
--- /dev/null
+++ b/security/nss/lib/ssl/sslmutex.h
@@ -0,0 +1,129 @@
+/* This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
+#ifndef __SSLMUTEX_H_
+#define __SSLMUTEX_H_ 1
+
+/* What SSL really wants is portable process-shared unnamed mutexes in
+ * shared memory, that have the property that if the process that holds
+ * them dies, they are released automatically, and that (unlike fcntl
+ * record locking) lock to the thread, not to the process.
+ * NSPR doesn't provide that.
+ * Windows has mutexes that meet that description, but they're not portable.
+ * POSIX mutexes are not automatically released when the holder dies,
+ * and other processes/threads cannot release the mutex on behalf of the
+ * dead holder.
+ * POSIX semaphores can be used to accomplish this on systems that implement
+ * process-shared unnamed POSIX semaphores, because a watchdog thread can
+ * discover and release semaphores that were held by a dead process.
+ * On systems that do not support process-shared POSIX unnamed semaphores,
+ * they can be emulated using pipes.
+ * The performance cost of doing that is not yet measured.
+ *
+ * So, this API looks a lot like POSIX pthread mutexes.
+ */
+
+#include "prtypes.h"
+#include "prlock.h"
+
+#if defined(NETBSD)
+#include <sys/param.h> /* for __NetBSD_Version__ */
+#endif
+
+#if defined(WIN32)
+
+#include <wtypes.h>
+
+typedef struct {
+    PRBool isMultiProcess;
+#ifdef WINNT
+    /* on WINNT we need both the PRLock and the Win32 mutex for fibers */
+    struct {
+#else
+    union {
+#endif
+        PRLock *sslLock;
+        HANDLE sslMutx;
+    } u;
+} sslMutex;
+
+typedef int sslPID;
+
+#elif defined(LINUX) || defined(AIX) || defined(BSDI) || \
+    (defined(NETBSD) && __NetBSD_Version__ < 500000000) || defined(OPENBSD) || defined(__GLIBC__)
+
+#include <sys/types.h>
+#include "prtypes.h"
+
+typedef struct {
+    PRBool isMultiProcess;
+    union {
+        PRLock *sslLock;
+        struct {
+            int mPipes[3];
+            PRInt32 nWaiters;
+        } pipeStr;
+    } u;
+} sslMutex;
+typedef pid_t sslPID;
+
+/* other types of unix, except OS X */
+#elif defined(XP_UNIX) && !defined(DARWIN)
+
+#include <sys/types.h> /* for pid_t */
+#include <semaphore.h> /* for sem_t, and sem_* functions */
+
+typedef struct {
+    PRBool isMultiProcess;
+    union {
+        PRLock *sslLock;
+        sem_t sem;
+    } u;
+} sslMutex;
+
+typedef pid_t sslPID;
+
+#else /* no support for cross-process locking */
+
+/* what platform is this ?? */
+
+typedef struct {
+    PRBool isMultiProcess;
+    union {
+        PRLock *sslLock;
+        /* include cross-process locking mechanism here */
+    } u;
+} sslMutex;
+
+#ifdef DARWIN
+typedef pid_t sslPID;
+#else
+typedef int sslPID;
+#endif
+
+#endif
+
+#include "seccomon.h"
+
+SEC_BEGIN_PROTOS
+
+extern SECStatus sslMutex_Init(sslMutex *sem, int shared);
+
+/* If processLocal is set to true, then just free resources which are *only* associated
+ * with the current process. Leave any shared resources (including the state of
+ * shared memory) intact. */
+extern SECStatus sslMutex_Destroy(sslMutex *sem, PRBool processLocal);
+
+extern SECStatus sslMutex_Unlock(sslMutex *sem);
+
+extern SECStatus sslMutex_Lock(sslMutex *sem);
+
+#ifdef WINNT
+
+extern SECStatus sslMutex_2LevelInit(sslMutex *sem);
+
+#endif
+
+SEC_END_PROTOS
+
+#endif