summaryrefslogtreecommitdiff
path: root/mozilla/nsprpub/pr/include/pripcsem.h
diff options
context:
space:
mode:
authorLorry Tar Creator <lorry-tar-importer@baserock.org>2011-08-09 15:52:57 +0000
committerLorry <lorry@roadtrain.codethink.co.uk>2012-09-25 08:55:51 +0000
commitc52067ca0b79daf6ffae5376481e6fef74849254 (patch)
tree9a4b19451eb85dcd6e16afb9d49a45a2f4f5aa83 /mozilla/nsprpub/pr/include/pripcsem.h
parent40d4517c5b760454c076064fac192b28a22e7a37 (diff)
downloadnspr-c52067ca0b79daf6ffae5376481e6fef74849254.tar.gz
Imported from /srv/lorry/lorry-area/nspr/nspr-4.8.9.tar.gz.HEADnspr-4.8.9master
Diffstat (limited to 'mozilla/nsprpub/pr/include/pripcsem.h')
-rw-r--r--mozilla/nsprpub/pr/include/pripcsem.h133
1 files changed, 133 insertions, 0 deletions
diff --git a/mozilla/nsprpub/pr/include/pripcsem.h b/mozilla/nsprpub/pr/include/pripcsem.h
new file mode 100644
index 0000000..5a96be5
--- /dev/null
+++ b/mozilla/nsprpub/pr/include/pripcsem.h
@@ -0,0 +1,133 @@
+/* -*- Mode: C++; tab-width: 4; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
+/* ***** BEGIN LICENSE BLOCK *****
+ * Version: MPL 1.1/GPL 2.0/LGPL 2.1
+ *
+ * The contents of this file are subject to the Mozilla Public License Version
+ * 1.1 (the "License"); you may not use this file except in compliance with
+ * the License. You may obtain a copy of the License at
+ * http://www.mozilla.org/MPL/
+ *
+ * Software distributed under the License is distributed on an "AS IS" basis,
+ * WITHOUT WARRANTY OF ANY KIND, either express or implied. See the License
+ * for the specific language governing rights and limitations under the
+ * License.
+ *
+ * The Original Code is the Netscape Portable Runtime (NSPR).
+ *
+ * The Initial Developer of the Original Code is
+ * Netscape Communications Corporation.
+ * Portions created by the Initial Developer are Copyright (C) 1999-2000
+ * the Initial Developer. All Rights Reserved.
+ *
+ * Contributor(s):
+ *
+ * Alternatively, the contents of this file may be used under the terms of
+ * either the GNU General Public License Version 2 or later (the "GPL"), or
+ * the GNU Lesser General Public License Version 2.1 or later (the "LGPL"),
+ * in which case the provisions of the GPL or the LGPL are applicable instead
+ * of those above. If you wish to allow use of your version of this file only
+ * under the terms of either the GPL or the LGPL, and not to allow others to
+ * use your version of this file under the terms of the MPL, indicate your
+ * decision by deleting the provisions above and replace them with the notice
+ * and other provisions required by the GPL or the LGPL. If you do not delete
+ * the provisions above, a recipient may use your version of this file under
+ * the terms of any one of the MPL, the GPL or the LGPL.
+ *
+ * ***** END LICENSE BLOCK ***** */
+
+/*
+ * File: pripcsem.h
+ *
+ * Description: named semaphores for interprocess
+ * synchronization
+ *
+ * Unrelated processes obtain access to a shared semaphore
+ * by specifying its name.
+ *
+ * Our goal is to support named semaphores on at least
+ * Unix and Win32 platforms. The implementation will use
+ * one of the three native semaphore APIs: POSIX, System V,
+ * and Win32.
+ *
+ * Because POSIX named semaphores have kernel persistence,
+ * we are forced to have a delete function in this API.
+ */
+
+#ifndef pripcsem_h___
+#define pripcsem_h___
+
+#include "prtypes.h"
+#include "prio.h"
+
+PR_BEGIN_EXTERN_C
+
+/*
+ * PRSem is an opaque structure that represents a named
+ * semaphore.
+ */
+typedef struct PRSem PRSem;
+
+/*
+ * PR_OpenSemaphore --
+ *
+ * Create or open a named semaphore with the specified name.
+ * A handle to the semaphore is returned.
+ *
+ * If the named semaphore doesn't exist and the PR_SEM_CREATE
+ * flag is specified, the named semaphore is created. The
+ * created semaphore needs to be removed from the system with
+ * a PR_DeleteSemaphore call.
+ *
+ * If PR_SEM_CREATE is specified, the third argument is the
+ * access permission bits of the new semaphore (same
+ * interpretation as the mode argument to PR_Open) and the
+ * fourth argument is the initial value of the new semaphore.
+ * If PR_SEM_CREATE is not specified, the third and fourth
+ * arguments are ignored.
+ */
+
+#define PR_SEM_CREATE 0x1 /* create if not exist */
+#define PR_SEM_EXCL 0x2 /* fail if already exists */
+
+NSPR_API(PRSem *) PR_OpenSemaphore(
+ const char *name, PRIntn flags, PRIntn mode, PRUintn value);
+
+/*
+ * PR_WaitSemaphore --
+ *
+ * If the value of the semaphore is > 0, decrement the value and return.
+ * If the value is 0, sleep until the value becomes > 0, then decrement
+ * the value and return.
+ *
+ * The "test and decrement" operation is performed atomically.
+ */
+
+NSPR_API(PRStatus) PR_WaitSemaphore(PRSem *sem);
+
+/*
+ * PR_PostSemaphore --
+ *
+ * Increment the value of the named semaphore by 1.
+ */
+
+NSPR_API(PRStatus) PR_PostSemaphore(PRSem *sem);
+
+/*
+ * PR_CloseSemaphore --
+ *
+ * Close a named semaphore handle.
+ */
+
+NSPR_API(PRStatus) PR_CloseSemaphore(PRSem *sem);
+
+/*
+ * PR_DeleteSemaphore --
+ *
+ * Remove a named semaphore from the system.
+ */
+
+NSPR_API(PRStatus) PR_DeleteSemaphore(const char *name);
+
+PR_END_EXTERN_C
+
+#endif /* pripcsem_h___ */