Renamed folders and separated GSF.Media and GSF.Net into separate projects.

StephenCWills committed 14 years ago

Commit ac1ef661 parent 45bce55628 files · +733 −461Browse files

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	1	//*******************************************************************************************************
	2	// InterprocessLock.cs - Gbtc
	3	//
	4	// Tennessee Valley Authority, 2011
	5	// No copyright is claimed pursuant to 17 USC § 105. All Other Rights Reserved.
	6	//
	7	// This software is made freely available under the TVA Open Source Agreement (see below).
	8	// Code in this file licensed to GSF under one or more contributor license agreements listed below.
	9	//
	10	// Code Modification History:
	11	// -----------------------------------------------------------------------------------------------------
	12	// 03/21/2011 - J. Ritchie Carroll
	13	// Generated original version of source code.
	14	// 06/30/2011 - Stephen Wills
	15	// Applying changes from Jian (Ryan) Zuo: updated to allow unauthorized users to attempt to grant
	16	// themselves lower than full access to existing mutexes and semaphores.
	17	// 08/12/2011 - J. Ritchie Carroll
	18	// Modified creation methods such that locking natives are created in a synchronized fashion.
	19	// 09/21/2011 - J. Ritchie Carroll
	20	// Added Mono implementation exception regions.
	21	//
	22	//*******************************************************************************************************
	23
	24	#region [ TVA Open Source Agreement ]
	25	/*
	26
	27	THIS OPEN SOURCE AGREEMENT ("AGREEMENT") DEFINES THE RIGHTS OF USE,REPRODUCTION, DISTRIBUTION,
	28	MODIFICATION AND REDISTRIBUTION OF CERTAIN COMPUTER SOFTWARE ORIGINALLY RELEASED BY THE
	29	TENNESSEE VALLEY AUTHORITY, A CORPORATE AGENCY AND INSTRUMENTALITY OF THE UNITED STATES GOVERNMENT
	30	("GOVERNMENT AGENCY"). GOVERNMENT AGENCY IS AN INTENDED THIRD-PARTY BENEFICIARY OF ALL SUBSEQUENT
	31	DISTRIBUTIONS OR REDISTRIBUTIONS OF THE SUBJECT SOFTWARE. ANYONE WHO USES, REPRODUCES, DISTRIBUTES,
	32	MODIFIES OR REDISTRIBUTES THE SUBJECT SOFTWARE, AS DEFINED HEREIN, OR ANY PART THEREOF, IS, BY THAT
	33	ACTION, ACCEPTING IN FULL THE RESPONSIBILITIES AND OBLIGATIONS CONTAINED IN THIS AGREEMENT.
	34
	35	Original Software Designation: openPDC
	36	Original Software Title: The GSF Open Source Phasor Data Concentrator
	37	User Registration Requested. Please Visit https://naspi.tva.com/Registration/
	38	Point of Contact for Original Software: J. Ritchie Carroll <mailto:jrcarrol@tva.gov>
	39
	40	1. DEFINITIONS
	41
	42	A. "Contributor" means Government Agency, as the developer of the Original Software, and any entity
	43	that makes a Modification.
	44
	45	B. "Covered Patents" mean patent claims licensable by a Contributor that are necessarily infringed by
	46	the use or sale of its Modification alone or when combined with the Subject Software.
	47
	48	C. "Display" means the showing of a copy of the Subject Software, either directly or by means of an
	49	image, or any other device.
	50
	51	D. "Distribution" means conveyance or transfer of the Subject Software, regardless of means, to
	52	another.
	53
	54	E. "Larger Work" means computer software that combines Subject Software, or portions thereof, with
	55	software separate from the Subject Software that is not governed by the terms of this Agreement.
	56
	57	F. "Modification" means any alteration of, including addition to or deletion from, the substance or
	58	structure of either the Original Software or Subject Software, and includes derivative works, as that
	59	term is defined in the Copyright Statute, 17 USC § 101. However, the act of including Subject Software
	60	as part of a Larger Work does not in and of itself constitute a Modification.
	61
	62	G. "Original Software" means the computer software first released under this Agreement by Government
	63	Agency entitled openPDC, including source code, object code and accompanying documentation, if any.
	64
	65	H. "Recipient" means anyone who acquires the Subject Software under this Agreement, including all
	66	Contributors.
	67
	68	I. "Redistribution" means Distribution of the Subject Software after a Modification has been made.
	69
	70	J. "Reproduction" means the making of a counterpart, image or copy of the Subject Software.
	71
	72	K. "Sale" means the exchange of the Subject Software for money or equivalent value.
	73
	74	L. "Subject Software" means the Original Software, Modifications, or any respective parts thereof.
	75
	76	M. "Use" means the application or employment of the Subject Software for any purpose.
	77
	78	2. GRANT OF RIGHTS
	79
	80	A. Under Non-Patent Rights: Subject to the terms and conditions of this Agreement, each Contributor,
	81	with respect to its own contribution to the Subject Software, hereby grants to each Recipient a
	82	non-exclusive, world-wide, royalty-free license to engage in the following activities pertaining to
	83	the Subject Software:
	84
	85	1. Use
	86
	87	2. Distribution
	88
	89	3. Reproduction
	90
	91	4. Modification
	92
	93	5. Redistribution
	94
	95	6. Display
	96
	97	B. Under Patent Rights: Subject to the terms and conditions of this Agreement, each Contributor, with
	98	respect to its own contribution to the Subject Software, hereby grants to each Recipient under Covered
	99	Patents a non-exclusive, world-wide, royalty-free license to engage in the following activities
	100	pertaining to the Subject Software:
	101
	102	1. Use
	103
	104	2. Distribution
	105
	106	3. Reproduction
	107
	108	4. Sale
	109
	110	5. Offer for Sale
	111
	112	C. The rights granted under Paragraph B. also apply to the combination of a Contributor's Modification
	113	and the Subject Software if, at the time the Modification is added by the Contributor, the addition of
	114	such Modification causes the combination to be covered by the Covered Patents. It does not apply to
	115	any other combinations that include a Modification.
	116
	117	D. The rights granted in Paragraphs A. and B. allow the Recipient to sublicense those same rights.
	118	Such sublicense must be under the same terms and conditions of this Agreement.
	119
	120	3. OBLIGATIONS OF RECIPIENT
	121
	122	A. Distribution or Redistribution of the Subject Software must be made under this Agreement except for
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	124
	125	1. Whenever a Recipient distributes or redistributes the Subject Software, a copy of this Agreement
	126	must be included with each copy of the Subject Software; and
	127
	128	2. If Recipient distributes or redistributes the Subject Software in any form other than source code,
	129	Recipient must also make the source code freely available, and must provide with each copy of the
	130	Subject Software information on how to obtain the source code in a reasonable manner on or through a
	131	medium customarily used for software exchange.
	132
	133	B. Each Recipient must ensure that the following copyright notice appears prominently in the Subject
	134	Software:
	135
	136	No copyright is claimed pursuant to 17 USC § 105. All Other Rights Reserved.
	137
	138	C. Each Contributor must characterize its alteration of the Subject Software as a Modification and
	139	must identify itself as the originator of its Modification in a manner that reasonably allows
	140	subsequent Recipients to identify the originator of the Modification. In fulfillment of these
	141	requirements, Contributor must include a file (e.g., a change log file) that describes the alterations
	142	made and the date of the alterations, identifies Contributor as originator of the alterations, and
	143	consents to characterization of the alterations as a Modification, for example, by including a
	144	statement that the Modification is derived, directly or indirectly, from Original Software provided by
	145	Government Agency. Once consent is granted, it may not thereafter be revoked.
	146
	147	D. A Contributor may add its own copyright notice to the Subject Software. Once a copyright notice has
	148	been added to the Subject Software, a Recipient may not remove it without the express permission of
	149	the Contributor who added the notice.
	150
	151	E. A Recipient may not make any representation in the Subject Software or in any promotional,
	152	advertising or other material that may be construed as an endorsement by Government Agency or by any
	153	prior Recipient of any product or service provided by Recipient, or that may seek to obtain commercial
	154	advantage by the fact of Government Agency's or a prior Recipient's participation in this Agreement.
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	156	F. In an effort to track usage and maintain accurate records of the Subject Software, each Recipient,
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	159	shall be used for statistical purposes only. Once a Recipient makes a Modification available, it is
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	162
	163	G. Each Contributor represents that that its Modification does not violate any existing agreements,
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	167	H. A Recipient may choose to offer, and to charge a fee for, warranty, support, indemnity and/or
	168	liability obligations to one or more other Recipients of the Subject Software. A Recipient may do so,
	169	however, only on its own behalf and not on behalf of Government Agency or any other Recipient. Such a
	170	Recipient must make it absolutely clear that any such warranty, support, indemnity and/or liability
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	172	Agency and every other Recipient for any liability incurred by them as a result of warranty, support,
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	174
	175	I. A Recipient may create a Larger Work by combining Subject Software with separate software not
	176	governed by the terms of this agreement and distribute the Larger Work as a single product. In such
	177	case, the Recipient must make sure Subject Software, or portions thereof, included in the Larger Work
	178	is subject to this Agreement.
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	180	J. Notwithstanding any provisions contained herein, Recipient is hereby put on notice that export of
	181	any goods or technical data from the United States may require some form of export license from the
	182	U.S. Government. Failure to obtain necessary export licenses may result in criminal liability under
	183	U.S. laws. Government Agency neither represents that a license shall not be required nor that, if
	184	required, it shall be issued. Nothing granted herein provides any such export license.
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	186	4. DISCLAIMER OF WARRANTIES AND LIABILITIES; WAIVER AND INDEMNIFICATION
	187
	188	A. No Warranty: THE SUBJECT SOFTWARE IS PROVIDED "AS IS" WITHOUT ANY WARRANTY OF ANY KIND, EITHER
	189	EXPRESSED, IMPLIED, OR STATUTORY, INCLUDING, BUT NOT LIMITED TO, ANY WARRANTY THAT THE SUBJECT
	190	SOFTWARE WILL CONFORM TO SPECIFICATIONS, ANY IMPLIED WARRANTIES OF MERCHANTABILITY, FITNESS FOR A
	191	PARTICULAR PURPOSE, OR FREEDOM FROM INFRINGEMENT, ANY WARRANTY THAT THE SUBJECT SOFTWARE WILL BE ERROR
	192	FREE, OR ANY WARRANTY THAT DOCUMENTATION, IF PROVIDED, WILL CONFORM TO THE SUBJECT SOFTWARE. THIS
	193	AGREEMENT DOES NOT, IN ANY MANNER, CONSTITUTE AN ENDORSEMENT BY GOVERNMENT AGENCY OR ANY PRIOR
	194	RECIPIENT OF ANY RESULTS, RESULTING DESIGNS, HARDWARE, SOFTWARE PRODUCTS OR ANY OTHER APPLICATIONS
	195	RESULTING FROM USE OF THE SUBJECT SOFTWARE. FURTHER, GOVERNMENT AGENCY DISCLAIMS ALL WARRANTIES AND
	196	LIABILITIES REGARDING THIRD-PARTY SOFTWARE, IF PRESENT IN THE ORIGINAL SOFTWARE, AND DISTRIBUTES IT
	197	"AS IS."
	198
	199	B. Waiver and Indemnity: RECIPIENT AGREES TO WAIVE ANY AND ALL CLAIMS AGAINST GOVERNMENT AGENCY, ITS
	200	AGENTS, EMPLOYEES, CONTRACTORS AND SUBCONTRACTORS, AS WELL AS ANY PRIOR RECIPIENT. IF RECIPIENT'S USE
	201	OF THE SUBJECT SOFTWARE RESULTS IN ANY LIABILITIES, DEMANDS, DAMAGES, EXPENSES OR LOSSES ARISING FROM
	202	SUCH USE, INCLUDING ANY DAMAGES FROM PRODUCTS BASED ON, OR RESULTING FROM, RECIPIENT'S USE OF THE
	203	SUBJECT SOFTWARE, RECIPIENT SHALL INDEMNIFY AND HOLD HARMLESS GOVERNMENT AGENCY, ITS AGENTS,
	204	EMPLOYEES, CONTRACTORS AND SUBCONTRACTORS, AS WELL AS ANY PRIOR RECIPIENT, TO THE EXTENT PERMITTED BY
	205	LAW. THE FOREGOING RELEASE AND INDEMNIFICATION SHALL APPLY EVEN IF THE LIABILITIES, DEMANDS, DAMAGES,
	206	EXPENSES OR LOSSES ARE CAUSED, OCCASIONED, OR CONTRIBUTED TO BY THE NEGLIGENCE, SOLE OR CONCURRENT, OF
	207	GOVERNMENT AGENCY OR ANY PRIOR RECIPIENT. RECIPIENT'S SOLE REMEDY FOR ANY SUCH MATTER SHALL BE THE
	208	IMMEDIATE, UNILATERAL TERMINATION OF THIS AGREEMENT.
	209
	210	5. GENERAL TERMS
	211
	212	A. Termination: This Agreement and the rights granted hereunder will terminate automatically if a
	213	Recipient fails to comply with these terms and conditions, and fails to cure such noncompliance within
	214	thirty (30) days of becoming aware of such noncompliance. Upon termination, a Recipient agrees to
	215	immediately cease use and distribution of the Subject Software. All sublicenses to the Subject
	216	Software properly granted by the breaching Recipient shall survive any such termination of this
	217	Agreement.
	218
	219	B. Severability: If any provision of this Agreement is invalid or unenforceable under applicable law,
	220	it shall not affect the validity or enforceability of the remainder of the terms of this Agreement.
	221
	222	C. Applicable Law: This Agreement shall be subject to United States federal law only for all purposes,
	223	including, but not limited to, determining the validity of this Agreement, the meaning of its
	224	provisions and the rights, obligations and remedies of the parties.
	225
	226	D. Entire Understanding: This Agreement constitutes the entire understanding and agreement of the
	227	parties relating to release of the Subject Software and may not be superseded, modified or amended
	228	except by further written agreement duly executed by the parties.
	229
	230	E. Binding Authority: By accepting and using the Subject Software under this Agreement, a Recipient
	231	affirms its authority to bind the Recipient to all terms and conditions of this Agreement and that
	232	Recipient hereby agrees to all terms and conditions herein.
	233
	234	F. Point of Contact: Any Recipient contact with Government Agency is to be directed to the designated
	235	representative as follows: J. Ritchie Carroll <mailto:jrcarrol@tva.gov>.
	236
	237	*/
	238	#endregion
	239
	240	#region [ Contributor License Agreements ]
	241
	242	//******************************************************************************************************
	243	//
	244	// Copyright © 2011, Grid Protection Alliance. All Rights Reserved.
	245	//
	246	// The GPA licenses this file to you under the Eclipse Public License -v 1.0 (the "License"); you may
	247	// not use this file except in compliance with the License. You may obtain a copy of the License at:
	248	//
	249	// http://www.opensource.org/licenses/eclipse-1.0.php
	250	//
	251	// Unless agreed to in writing, the subject software distributed under the License is distributed on an
	252	// "AS-IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. Refer to the
	253	// License for the specific language governing permissions and limitations.
	254	//
	255	//******************************************************************************************************
	256
	257	#endregion
	258
	259	using GSF.Security.Cryptography;
	260	using System;
	261	using System.Runtime.CompilerServices;
	262	using System.Security.AccessControl;
	263	using System.Security.Principal;
	264	using System.Threading;
	265
	266	namespace GSF.Threading
	267	{
	268	/// <summary>
	269	/// Defines helper methods related to interprocess locking.
	270	/// </summary>
	271	public static class InterprocessLock
	272	{
	273	private const int MutexHash = 0;
	274	private const int SemaphoreHash = 1;
	275
	276	/// <summary>
	277	/// Gets a uniquely named interprocess <see cref="Mutex"/> associated with the specified <paramref name="name"/> that identifies a source object
	278	/// needing concurrency locking.
	279	/// </summary>
	280	/// <param name="name">Identifiying name of source object needing concurrency locking (e.g., a path and file name).</param>
	281	/// <returns>A uniquely named interprocess <see cref="Mutex"/> specific to <paramref name="name"/>; <see cref="Mutex"/> is created if it does not exist.</returns>
	282	/// <remarks>
	283	/// <para>
	284	/// This function uses a hash of the <paramref name="name"/> when creating the <see cref="Mutex"/>, not the actual <paramref name="name"/> - this way
	285	/// restrictions on the <paramref name="name"/> do not need to be a user concern. All processes needing an interprocess <see cref="Mutex"/> need to
	286	/// use this same function to ensure access to the same <see cref="Mutex"/>.
	287	/// </para>
	288	/// <para>
	289	/// The <paramref name="name"/> can be a string of any length (must not be empty, null or white space) and is not case-sensitive. All hashes of the
	290	/// <paramref name="name"/> used to create the global <see cref="Mutex"/> are first converted to lower case.
	291	/// </para>
	292	/// <para>
	293	/// The <see cref="Mutex"/> created is "Global" meaning that it will be accessible to all active application sessions including terminal service
	294	/// sessions. This is accomplished internally by prefixing the <see cref="Mutex"/> name with "Global\"; it is not necessary for the user to be
	295	/// concerned with the length or contents of the <paramref name="name"/> in this method as long as the same <paramref name="name"/> is used for
	296	/// each application. Do not use this helper function if you need to create a specifically named or non-global <see cref="Mutex"/>, such as when
	297	/// you need to interact with another application using a <see cref="Mutex"/> that does not use this function.
	298	/// </para>
	299	/// </remarks>
	300	/// <exception cref="ArgumentNullException">Argument <paramref name="name"/> cannot be empty, null or white space.</exception>
	301	[MethodImplAttribute(MethodImplOptions.Synchronized)]
	302	public static Mutex GetNamedMutex(string name)
	303	{
	304	if (string.IsNullOrWhiteSpace(name))
	305	throw new ArgumentNullException("name", "Argument cannot be empty, null or white space.");
	306
	307	Mutex namedMutex = null;
	308	bool doesNotExist = false;
	309	bool unauthorized = false;
	310
	311	// Create a mutex name that is specific to an object (e.g., a path and file name).
	312	// Prefix mutext name with "Global\" such that mutex will apply to all active
	313	// application sessions in case terminal services is running.
	314	string mutexName = "Global\\" + Cipher.GetPasswordHash(name.ToLower(), MutexHash).Replace('\\', '-');
	315
	316	// Attempt to open the named mutex
	317	try
	318	{
	319	namedMutex = Mutex.OpenExisting(mutexName);
	320	}
	321	catch (WaitHandleCannotBeOpenedException)
	322	{
	323	doesNotExist = true;
	324	}
	325	catch (UnauthorizedAccessException)
	326	{
	327	unauthorized = true;
	328	}
	329
	330	// Mono Mutex implementations do not include ability to change access rules
	331	#if MONO
	332	// If mutex does not exist we create it
	333	if (doesNotExist \|\| unauthorized)
	334	{
	335	try
	336	{
	337	bool mutexWasCreated;
	338
	339	namedMutex = new Mutex(false, mutexName, out mutexWasCreated);
	340
	341	if (!mutexWasCreated)
	342	throw new InvalidOperationException("Failed to create mutex.");
	343	}
	344	catch (UnauthorizedAccessException ex)
	345	{
	346	throw new InvalidOperationException("Failed to create mutex: " + ex.Message);
	347	}
	348	}
	349	#else
	350	// If mutex does not exist we create it
	351	if (doesNotExist)
	352	{
	353	try
	354	{
	355	MutexSecurity security = new MutexSecurity();
	356	bool mutexWasCreated;
	357
	358	security.AddAccessRule(new MutexAccessRule(new SecurityIdentifier(WellKnownSidType.WorldSid, null), MutexRights.FullControl, AccessControlType.Allow));
	359	namedMutex = new Mutex(false, mutexName, out mutexWasCreated, security);
	360
	361	if (!mutexWasCreated)
	362	throw new InvalidOperationException("Failed to create mutex.");
	363	}
	364	catch (UnauthorizedAccessException)
	365	{
	366	MutexSecurity security = new MutexSecurity();
	367	bool mutexWasCreated;
	368
	369	security.AddAccessRule(new MutexAccessRule(new SecurityIdentifier(WellKnownSidType.WorldSid, null), MutexRights.Synchronize \| MutexRights.Modify, AccessControlType.Allow));
	370	namedMutex = new Mutex(false, mutexName, out mutexWasCreated, security);
	371
	372	if (!mutexWasCreated)
	373	throw new InvalidOperationException("Failed to create mutex.");
	374	}
	375	}
	376
	377	if (unauthorized)
	378	{
	379	namedMutex = Mutex.OpenExisting(mutexName, MutexRights.ReadPermissions \| MutexRights.ChangePermissions);
	380
	381	// Get the current ACL. This requires MutexRights.ReadPermission
	382	MutexSecurity security = namedMutex.GetAccessControl();
	383	MutexAccessRule rule = new MutexAccessRule(new SecurityIdentifier(WellKnownSidType.WorldSid, null), MutexRights.FullControl, AccessControlType.Allow);
	384	security.RemoveAccessRule(rule);
	385
	386	// Now grant specific user rights for less than full access
	387	rule = new MutexAccessRule(new SecurityIdentifier(WellKnownSidType.WorldSid, null), MutexRights.Synchronize \| MutexRights.Modify, AccessControlType.Allow);
	388	security.AddAccessRule(rule);
	389
	390	// Update the ACL. This requires MutexRighs.ChangePermission.
	391	namedMutex.SetAccessControl(security);
	392	namedMutex = Mutex.OpenExisting(mutexName);
	393	}
	394	#endif
	395
	396	return namedMutex;
	397	}
	398
	399	/// <summary>
	400	/// Gets a uniquely named interprocess <see cref="Semaphore"/> associated with the specified <paramref name="name"/> that identifies a source object
	401	/// needing concurrency locking.
	402	/// </summary>
	403	/// <param name="name">Identifiying name of source object needing concurrency locking (e.g., a path and file name).</param>
	404	/// <param name="maximumCount">The maximum number of requests for the semaphore that can be granted concurrently.</param>
	405	/// <param name="initialCount">The initial number of requests for the semaphore that can be granted concurrently, or -1 to default to <paramref name="maximumCount"/>.</param>
	406	/// <returns>A uniquely named interprocess <see cref="Semaphore"/> specific to <paramref name="name"/>; <see cref="Semaphore"/> is created if it does not exist.</returns>
	407	/// <remarks>
	408	/// <para>
	409	/// This function uses a hash of the <paramref name="name"/> when creating the <see cref="Semaphore"/>, not the actual <paramref name="name"/> - this way
	410	/// restrictions on the <paramref name="name"/> do not need to be a user concern. All processes needing an interprocess <see cref="Semaphore"/> need to
	411	/// use this same function to ensure access to the same <see cref="Semaphore"/>.
	412	/// </para>
	413	/// <para>
	414	/// The <paramref name="name"/> can be a string of any length (must not be empty, null or white space) and is not case-sensitive. All hashes of the
	415	/// <paramref name="name"/> used to create the global <see cref="Semaphore"/> are first converted to lower case.
	416	/// </para>
	417	/// <para>
	418	/// It is not necessary for the user to be concerned with the length or contents of the <paramref name="name"/> in this method as long as the same
	419	/// <paramref name="name"/> is used for each application. Do not use this helper function if you need to create a specifically named <see cref="Semaphore"/>,
	420	/// such as when you need to interact with another application using a <see cref="Semaphore"/> that does not use this function.
	421	/// </para>
	422	/// </remarks>
	423	/// <exception cref="ArgumentNullException">Argument <paramref name="name"/> cannot be empty, null or white space.</exception>
	424	[MethodImplAttribute(MethodImplOptions.Synchronized)]
	425	public static Semaphore GetNamedSemaphore(string name, int maximumCount = 10, int initialCount = -1)
	426	{
	427	if (string.IsNullOrWhiteSpace(name))
	428	throw new ArgumentNullException("name", "Argument cannot be empty, null or white space.");
	429
	430	Semaphore namedSemaphore = null;
	431	bool doesNotExist = false;
	432	bool unauthorized = false;
	433
	434	if (initialCount < 0)
	435	initialCount = maximumCount;
	436
	437	// Create a semaphore name that is specific to an object (e.g., a path and file name).
	438	string semaphoreName = Cipher.GetPasswordHash(name.ToLower(), SemaphoreHash).Replace('\\', '-');
	439
	440	// Attempt to open the named semaphore
	441	try
	442	{
	443	namedSemaphore = Semaphore.OpenExisting(semaphoreName);
	444	}
	445	catch (WaitHandleCannotBeOpenedException)
	446	{
	447	doesNotExist = true;
	448	}
	449	catch (UnauthorizedAccessException)
	450	{
	451	unauthorized = true;
	452	}
	453
	454	// Mono Semaphore implementations do not include ability to change access rules
	455	#if MONO
	456	// If semaphore does not exist we create it
	457	if (doesNotExist \|\| unauthorized)
	458	{
	459	try
	460	{
	461	bool semaphoreWasCreated;
	462
	463	namedSemaphore = new Semaphore(initialCount, maximumCount, semaphoreName, out semaphoreWasCreated);
	464
	465	if (!semaphoreWasCreated)
	466	throw new InvalidOperationException("Failed to create semaphore.");
	467	}
	468	catch (UnauthorizedAccessException ex)
	469	{
	470	throw new InvalidOperationException("Failed to create semaphore: " + ex.Message);
	471	}
	472	}
	473	#else
	474	// If semaphore does not exist we create it
	475	if (doesNotExist)
	476	{
	477	try
	478	{
	479	SemaphoreSecurity security = new SemaphoreSecurity();
	480	bool semaphoreWasCreated;
	481
	482	security.AddAccessRule(new SemaphoreAccessRule(new SecurityIdentifier(WellKnownSidType.WorldSid, null), SemaphoreRights.FullControl, AccessControlType.Allow));
	483	namedSemaphore = new Semaphore(initialCount, maximumCount, semaphoreName, out semaphoreWasCreated, security);
	484
	485	if (!semaphoreWasCreated)
	486	throw new InvalidOperationException("Failed to create semaphore.");
	487	}
	488	catch (UnauthorizedAccessException)
	489	{
	490	SemaphoreSecurity security = new SemaphoreSecurity();
	491	bool semaphoreWasCreated;
	492
	493	security.AddAccessRule(new SemaphoreAccessRule(new SecurityIdentifier(WellKnownSidType.WorldSid, null), SemaphoreRights.Synchronize \| SemaphoreRights.Modify, AccessControlType.Allow));
	494	namedSemaphore = new Semaphore(initialCount, maximumCount, semaphoreName, out semaphoreWasCreated, security);
	495
	496	if (!semaphoreWasCreated)
	497	throw new InvalidOperationException("Failed to create semaphore.");
	498	}
	499	}
	500	else if (unauthorized)
	501	{
	502	namedSemaphore = Semaphore.OpenExisting(semaphoreName, SemaphoreRights.ReadPermissions \| SemaphoreRights.ChangePermissions);
	503
	504	// Get the current ACL. This requires MutexRights.ReadPermission
	505	SemaphoreSecurity security = new SemaphoreSecurity();
	506	SemaphoreAccessRule rule = new SemaphoreAccessRule(new SecurityIdentifier(WellKnownSidType.WorldSid, null), SemaphoreRights.FullControl, AccessControlType.Allow);
	507	security.RemoveAccessRule(rule);
	508
	509	// Now grant specific user rights for less than full access
	510	rule = new SemaphoreAccessRule(new SecurityIdentifier(WellKnownSidType.WorldSid, null), SemaphoreRights.Synchronize \| SemaphoreRights.Modify, AccessControlType.Allow);
	511	security.AddAccessRule(rule);
	512
	513	// Update the ACL. This requires MutexRighs.ChangePermission.
	514	namedSemaphore.SetAccessControl(security);
	515	namedSemaphore = Semaphore.OpenExisting(semaphoreName);
	516	}
	517	#endif
	518
	519	return namedSemaphore;
	520	}
	521	}
	522	}

Renamed folders and separated GSF.Media and GSF.Net into separate projects.

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