add initial demo pthread party

Everything in order here. Party results:

Before party:
FOOD:  [ *********** ]
TRASH: [             ]

After party:
FOOD:  [             ]
TRASH: [ *********** ]

Everyone ate in order and then placed their trash accordingly.
Locking is in place so this is expected.

Signed-off-by: Luis R. Rodriguez <mcgrof@kernel.org>

6 files changed, 424 insertions, 0 deletions

diff --git a/.gitignore b/.gitignore
new file mode 100644
index 0000000..87e54c2
--- /dev/null
+++ b/.gitignore
@@ -0,0 +1,2 @@
+main
+*.o
diff --git a/CONTRIBUTING b/CONTRIBUTING
new file mode 100644
index 0000000..0ad2ce6
--- /dev/null
+++ b/CONTRIBUTING
@@ -0,0 +1,50 @@
+Send me patches: mcgrof@kernel.org
+
+This project embraces the Developer Certificate of Origin (DCO) for
+contributions. This means you must agree to the following prior to submitting
+patches, if you agree with this developer certificate you acknowledge this by
+adding a Signed-off-by tag to your patch commit log. Every submitted patch
+must have this.
+
+The source for the DCO:
+
+http://developercertificate.org/
+
+-----------------------------------------------------------------------
+
+Developer Certificate of Origin
+Version 1.1
+
+Copyright (C) 2004, 2006 The Linux Foundation and its contributors.
+660 York Street, Suite 102,
+San Francisco, CA 94110 USA
+
+Everyone is permitted to copy and distribute verbatim copies of this
+license document, but changing it is not allowed.
+
+
+Developer's Certificate of Origin 1.1
+
+By making a contribution to this project, I certify that:
+
+(a) The contribution was created in whole or in part by me and I
+    have the right to submit it under the open source license
+    indicated in the file; or
+
+(b) The contribution is based upon previous work that, to the best
+    of my knowledge, is covered under an appropriate open source
+    license and I have the right under that license to submit that
+    work with modifications, whether created in whole or in part
+    by me, under the same open source license (unless I am
+    permitted to submit under a different license), as indicated
+    in the file; or
+
+(c) The contribution was provided directly to me by some other
+    person who certified (a), (b) or (c) and I have not modified
+    it.
+
+(d) I understand and agree that this project and the contribution
+    are public and that a record of the contribution (including all
+    personal information I submit with it, including my sign-off) is
+    maintained indefinitely and may be redistributed consistent with
+    this project or the open source license(s) involved.
diff --git a/LICENSE b/LICENSE
new file mode 100644
index 0000000..a184d99
--- /dev/null
+++ b/LICENSE
@@ -0,0 +1,8 @@
+Copyright (c) 2016, Luis R. Rodriguez <mcgrof@kernel.org>
+
+CRDA is licensed under copyleft-next 0.3.1
+
+Refer to copyleft-next-0.3.1 for license details, you can
+also always get the latest updates of copyleft-next from:
+
+https://github.com/richardfontana/copyleft-next
diff --git a/Makefile b/Makefile
new file mode 100644
index 0000000..122bbfb
--- /dev/null
+++ b/Makefile
@@ -0,0 +1,7 @@
+all: main
+
+main: main.c
+	gcc -lpthread -o main main.c
+
+clean:
+	rm -f main
diff --git a/copyleft-next-0.3.1 b/copyleft-next-0.3.1
new file mode 100644
index 0000000..36d8515
--- /dev/null
+++ b/copyleft-next-0.3.1
@@ -0,0 +1,220 @@
+                      copyleft-next 0.3.1 ("this License")
+                            Release date: 2016-04-29
+
+1. License Grants; No Trademark License
+
+   Subject to the terms of this License, I grant You:
+
+   a) A non-exclusive, worldwide, perpetual, royalty-free, irrevocable
+      copyright license, to reproduce, Distribute, prepare derivative works
+      of, publicly perform and publicly display My Work.
+
+   b) A non-exclusive, worldwide, perpetual, royalty-free, irrevocable
+      patent license under Licensed Patents to make, have made, use, sell,
+      offer for sale, and import Covered Works.
+
+   This License does not grant any rights in My name, trademarks, service
+   marks, or logos.
+
+2. Distribution: General Conditions
+
+   You may Distribute Covered Works, provided that You (i) inform
+   recipients how they can obtain a copy of this License; (ii) satisfy the
+   applicable conditions of sections 3 through 6; and (iii) preserve all
+   Legal Notices contained in My Work (to the extent they remain
+   pertinent). "Legal Notices" means copyright notices, license notices,
+   license texts, and author attributions, but does not include logos,
+   other graphical images, trademarks or trademark legends.
+
+3. Conditions for Distributing Derived Works; Outbound GPL Compatibility
+
+   If You Distribute a Derived Work, You must license the entire Derived
+   Work as a whole under this License, with prominent notice of such
+   licensing. This condition may not be avoided through such means as
+   separate Distribution of portions of the Derived Work.
+
+   If the Derived Work includes material licensed under the GPL, You may
+   instead license the Derived Work under the GPL.
+   
+4. Condition Against Further Restrictions; Inbound License Compatibility
+
+   When Distributing a Covered Work, You may not impose further
+   restrictions on the exercise of rights in the Covered Work granted under
+   this License. This condition is not excused merely because such
+   restrictions result from Your compliance with conditions or obligations
+   extrinsic to this License (such as a court order or an agreement with a
+   third party).
+
+   However, You may Distribute a Covered Work incorporating material
+   governed by a license that is both OSI-Approved and FSF-Free as of the
+   release date of this License, provided that compliance with such
+   other license would not conflict with any conditions stated in other
+   sections of this License.
+
+5. Conditions for Distributing Object Code
+
+   You may Distribute an Object Code form of a Covered Work, provided that
+   you accompany the Object Code with a URL through which the Corresponding
+   Source is made available, at no charge, by some standard or customary
+   means of providing network access to source code.
+
+   If you Distribute the Object Code in a physical product or tangible
+   storage medium ("Product"), the Corresponding Source must be available
+   through such URL for two years from the date of Your most recent
+   Distribution of the Object Code in the Product. However, if the Product
+   itself contains or is accompanied by the Corresponding Source (made
+   available in a customarily accessible manner), You need not also comply
+   with the first paragraph of this section.
+
+   Each direct and indirect recipient of the Covered Work from You is an
+   intended third-party beneficiary of this License solely as to this
+   section 5, with the right to enforce its terms.
+
+6. Symmetrical Licensing Condition for Upstream Contributions
+
+   If You Distribute a work to Me specifically for inclusion in or
+   modification of a Covered Work (a "Patch"), and no explicit licensing
+   terms apply to the Patch, You license the Patch under this License, to
+   the extent of Your copyright in the Patch. This condition does not
+   negate the other conditions of this License, if applicable to the Patch.
+
+7. Nullification of Copyleft/Proprietary Dual Licensing
+
+   If I offer to license, for a fee, a Covered Work under terms other than
+   a license that is OSI-Approved or FSF-Free as of the release date of this
+   License or a numbered version of copyleft-next released by the
+   Copyleft-Next Project, then the license I grant You under section 1 is no
+   longer subject to the conditions in sections 3 through 5.
+
+8. Copyleft Sunset
+
+   The conditions in sections 3 through 5 no longer apply once fifteen
+   years have elapsed from the date of My first Distribution of My Work
+   under this License.
+
+9. Pass-Through
+
+   When You Distribute a Covered Work, the recipient automatically receives
+   a license to My Work from Me, subject to the terms of this License.
+
+10. Termination
+
+    Your license grants under section 1 are automatically terminated if You
+
+    a) fail to comply with the conditions of this License, unless You cure
+       such noncompliance within thirty days after becoming aware of it, or
+
+    b) initiate a patent infringement litigation claim (excluding
+       declaratory judgment actions, counterclaims, and cross-claims)
+       alleging that any part of My Work directly or indirectly infringes
+       any patent.
+
+    Termination of Your license grants extends to all copies of Covered
+    Works You subsequently obtain. Termination does not terminate the
+    rights of those who have received copies or rights from You subject to
+    this License.
+
+    To the extent permission to make copies of a Covered Work is necessary
+    merely for running it, such permission is not terminable.
+
+11. Later License Versions
+
+    The Copyleft-Next Project may release new versions of copyleft-next,
+    designated by a distinguishing version number ("Later Versions").
+    Unless I explicitly remove the option of Distributing Covered Works
+    under Later Versions, You may Distribute Covered Works under any Later
+    Version.
+
+** 12. No Warranty                                                       **
+**                                                                       **
+**     My Work is provided "as-is", without warranty. You bear the risk  **
+**     of using it. To the extent permitted by applicable law, each      **
+**     Distributor of My Work excludes the implied warranties of title,  **
+**     merchantability, fitness for a particular purpose and             **
+**     non-infringement.                                                 **
+
+** 13. Limitation of Liability                                           **
+**                                                                       **
+**     To the extent permitted by applicable law, in no event will any   **
+**     Distributor of My Work be liable to You for any damages           **
+**     whatsoever, whether direct, indirect, special, incidental, or     **
+**     consequential damages, whether arising under contract, tort       **
+**     (including negligence), or otherwise, even where the Distributor  **
+**     knew or should have known about the possibility of such damages.  **
+
+14. Severability
+
+    The invalidity or unenforceability of any provision of this License
+    does not affect the validity or enforceability of the remainder of
+    this License. Such provision is to be reformed to the minimum extent
+    necessary to make it valid and enforceable.
+
+15. Definitions
+
+    "Copyleft-Next Project" means the project that maintains the source
+    code repository at <https://github.com/copyleft-next/copyleft-next.git/>
+    as of the release date of this License.
+
+    "Corresponding Source" of a Covered Work in Object Code form means (i)
+    the Source Code form of the Covered Work; (ii) all scripts,
+    instructions and similar information that are reasonably necessary for
+    a skilled developer to generate such Object Code from the Source Code
+    provided under (i); and (iii) a list clearly identifying all Separate
+    Works (other than those provided in compliance with (ii)) that were
+    specifically used in building and (if applicable) installing the
+    Covered Work (for example, a specified proprietary compiler including
+    its version number). Corresponding Source must be machine-readable.
+
+    "Covered Work" means My Work or a Derived Work.
+
+    "Derived Work" means a work of authorship that copies from, modifies,
+    adapts, is based on, is a derivative work of, transforms, translates or
+    contains all or part of My Work, such that copyright permission is
+    required. The following are not Derived Works: (i) Mere Aggregation;
+    (ii) a mere reproduction of My Work; and (iii) if My Work fails to
+    explicitly state an expectation otherwise, a work that merely makes
+    reference to My Work.
+
+    "Distribute" means to distribute, transfer or make a copy available to
+    someone else, such that copyright permission is required.
+
+    "Distributor" means Me and anyone else who Distributes a Covered Work.
+
+    "FSF-Free" means classified as 'free' by the Free Software Foundation.
+
+    "GPL" means a version of the GNU General Public License or the GNU
+    Affero General Public License.
+
+    "I"/"Me"/"My" refers to the individual or legal entity that places My
+    Work under this License. "You"/"Your" refers to the individual or legal
+    entity exercising rights in My Work under this License. A legal entity
+    includes each entity that controls, is controlled by, or is under
+    common control with such legal entity. "Control" means (a) the power to
+    direct the actions of such legal entity, whether by contract or
+    otherwise, or (b) ownership of more than fifty percent of the
+    outstanding shares or beneficial ownership of such legal entity.
+
+    "Licensed Patents" means all patent claims licensable royalty-free by
+    Me, now or in the future, that are necessarily infringed by making,
+    using, or selling My Work, and excludes claims that would be infringed
+    only as a consequence of further modification of My Work.
+
+    "Mere Aggregation" means an aggregation of a Covered Work with a
+    Separate Work.
+
+    "My Work" means the particular work of authorship I license to You
+    under this License.
+
+    "Object Code" means any form of a work that is not Source Code.
+
+    "OSI-Approved" means approved as 'Open Source' by the Open Source
+    Initiative.
+
+    "Separate Work" means a work that is separate from and independent of a
+    particular Covered Work and is not by its nature an extension or
+    enhancement of the Covered Work, and/or a runtime library, standard
+    library or similar component that is used to generate an Object Code
+    form of a Covered Work.
+
+    "Source Code" means the preferred form of a work for making
+    modifications to it.
diff --git a/main.c b/main.c
new file mode 100644
index 0000000..f1fd83c
--- /dev/null
+++ b/main.c
@@ -0,0 +1,137 @@
+#include <pthread.h>
+#include <stdio.h>
+#include <stdlib.h>
+#include <errno.h>
+#include <unistd.h>
+#include <stdbool.h>
+#include <string.h>
+#define NUM_THREADS	11
+
+struct bin {
+	bool ready;
+	int food[NUM_THREADS+1];
+	int trash[NUM_THREADS+1];
+	pthread_mutex_t mutex;
+};
+
+struct party_ticket {
+	long threadid;
+	struct bin *party;
+};
+
+struct bin *party;
+
+void eat(long tid)
+{
+	bool eat_in_order = true;
+	long t;
+
+	/* If anyone ate out of place lets take notice of that... */
+	for (t=0; t < tid; t++) {
+		if (party->food[t])
+			eat_in_order = false;
+	}
+
+	if (party->food[tid])
+		party->food[tid] = 0;
+}
+
+void cleanup(long tid)
+{
+	bool clean_follow = true;
+	long t;
+
+	for (t=0; t < tid; t++) {
+		if (!party->trash[t])
+			clean_follow = false;
+	}
+
+	party->trash[tid] = 1;
+}
+
+void *thread_party(void *t)
+{
+	long tid = (long)t;
+
+	pthread_mutex_lock(&party->mutex);
+	eat(tid);
+
+	if (tid % 2 == 1)
+		sleep(1);
+
+	cleanup(tid);
+	pthread_mutex_unlock(&party->mutex);
+
+	pthread_exit(NULL);
+}
+
+void show_party(struct bin *party)
+{
+	long t;
+
+	printf("FOOD:  [ ");
+
+	for (t=0; t < NUM_THREADS; t++) {
+		if (party->food[t])
+			printf("*");
+		else
+			printf(" ");
+	}
+	printf(" ]\n");
+
+	printf("TRASH: [ ");
+	for (t=0; t < NUM_THREADS; t++) {
+		if (party->trash[t])
+			printf("*");
+		else
+			printf(" ");
+	}
+	printf(" ]\n");
+}
+
+int main(int argc, char *argv[])
+{
+	pthread_t threads[NUM_THREADS];
+	int ret;
+	long t;
+	pthread_attr_t attr;
+	void *status;
+
+	party = malloc(sizeof(struct bin));
+	if (!party)
+		return -ENOMEM;
+	memset(party, 0, sizeof(struct bin));
+	for (t=0; t <= NUM_THREADS; t++) {
+		party->food[t] = 1;
+		party->trash[t] = 0;
+	}
+	party->ready = true;
+
+	printf("Before party:\n");
+	show_party(party);
+
+	pthread_mutex_init(&party->mutex, NULL);
+
+	pthread_attr_init(&attr);
+	pthread_attr_setdetachstate(&attr, PTHREAD_CREATE_JOINABLE);
+
+	for (t=0; t < NUM_THREADS; t++) {
+		ret = pthread_create(&threads[t], &attr, thread_party, (void *)t);
+		if (ret){
+			printf("ERROR; return code from pthread_create() is %d\n", ret);
+			exit(-1);
+		}
+	}
+
+	pthread_attr_destroy(&attr);
+	for (t=0; t < NUM_THREADS; t++)
+		pthread_join(threads[t], &status);
+
+	printf("\nAfter party:\n");
+	show_party(party);
+
+	pthread_mutex_destroy(&party->mutex);
+	pthread_exit(NULL);
+
+	free(party);
+}