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Use *NSYNC for POSIX threads locking APIs

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Condition variables, barriers, and r/w locks now work very well.
This commit is contained in:
Justine Tunney 2022-09-11 11:02:07 -07:00
parent 3de35e196c
commit b5cb71ab84
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GPG key ID: BE714B4575D6E328
197 changed files with 3734 additions and 3817 deletions
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143
third_party/nsync/dll.c vendored Normal file
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/*-*- mode:c;indent-tabs-mode:t;c-basic-offset:8;tab-width:8;coding:utf-8 -*-│
│vi: set et ft=c ts=8 tw=8 fenc=utf-8 :vi│
╞══════════════════════════════════════════════════════════════════════════════╡
│ Copyright 2016 Google Inc. │
│ │
│ Licensed under the Apache License, Version 2.0 (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.apache.org/licenses/LICENSE-2.0 │
│ │
│ Unless required by applicable law or agreed to in writing, software │
│ distributed under the License is distributed on an "AS IS" BASIS, │
│ WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. │
│ See the License for the specific language governing permissions and │
│ limitations under the License. │
╚─────────────────────────────────────────────────────────────────────────────*/
#include "third_party/nsync/dll.h"
asm(".ident\t\"\\n\\n\
*NSYNC (Apache 2.0)\\n\
Copyright 2016 Google, Inc.\\n\
https://github.com/google/nsync\"");
// clang-format off
/* Initialize *e. */
void nsync_dll_init_ (nsync_dll_element_ *e, void *container) {
e->next = e;
e->prev = e;
e->container = container;
}
/* Return whether list is empty. */
int nsync_dll_is_empty_ (nsync_dll_list_ list) {
return (list == NULL);
}
/* Remove *e from list, and returns the new list. */
nsync_dll_list_ nsync_dll_remove_ (nsync_dll_list_ list, nsync_dll_element_ *e) {
if (list == e) { /* removing tail of list */
if (list->prev == list) {
list = NULL; /* removing only element of list */
} else {
list = list->prev;
}
}
e->next->prev = e->prev;
e->prev->next = e->next;
e->next = e;
e->prev = e;
return (list);
}
/* Cause element *n and its successors to come after element *p.
Requires n and p are non-NULL and do not point at elements of the same list.
Unlike the other operations in this API, this operation acts on
two circular lists of elements, rather than on a "head" location that points
to such a circular list.
If the two lists are p->p_2nd->p_mid->p_last->p and n->n_2nd->n_mid->n_last->n,
then after nsync_dll_splice_after_ (p, n), the p list would be:
p->n->n_2nd->n_mid->n_last->p_2nd->p_mid->p_last->p. */
void nsync_dll_splice_after_ (nsync_dll_element_ *p, nsync_dll_element_ *n) {
nsync_dll_element_ *p_2nd = p->next;
nsync_dll_element_ *n_last = n->prev;
p->next = n; /* n follows p */
n->prev = p;
n_last->next = p_2nd; /* remainder of p-list follows last of n-list */
p_2nd->prev = n_last;
}
/* Make element *e the first element of list, and return
the list. The resulting list will have *e as its first element, followed by
any elements in the same list as *e, followed by the elements that were
previously in list. Requires that *e not be in list. If e==NULL, list is
returned unchanged.
Suppose the e list is e->e_2nd->e_mid->e_last->e.
Recall that a head "list" points to the last element of its list.
If list is initially null, then the outcome is:
result = e_last->e->e_2nd->e_mid->e_last
If list is initially list->list_last->list_1st->list_mid->list_last,
then the outcome is:
result = list_last->e->e_2nd->e_mid->e_last->list_1st->list_mid->list_last
*/
nsync_dll_list_ nsync_dll_make_first_in_list_ (nsync_dll_list_ list, nsync_dll_element_ *e) {
if (e != NULL) {
if (list == NULL) {
list = e->prev; /*e->prev is e_last*/
} else {
nsync_dll_splice_after_ (list, e);
}
}
return (list);
}
/* Make element *e the last element of list, and return
the list. The resulting list will have *e as its last element, preceded by
any elements in the same list as *e, preceded by the elements that were
previously in list. Requires that *e not be in list. If e==NULL, list is
returned unchanged. */
nsync_dll_list_ nsync_dll_make_last_in_list_ (nsync_dll_list_ list, nsync_dll_element_ *e) {
if (e != NULL) {
nsync_dll_make_first_in_list_ (list, e->next);
list = e;
}
return (list);
}
/* Return a pointer to the first element of list, or NULL if list is empty. */
nsync_dll_element_ *nsync_dll_first_ (nsync_dll_list_ list) {
nsync_dll_element_ *first = NULL;
if (list != NULL) {
first = list->next;
}
return (first);
}
/* Return a pointer to the last element of list, or NULL if list is empty. */
nsync_dll_element_ *nsync_dll_last_ (nsync_dll_list_ list) {
return (list);
}
/* Return a pointer to the next element of list following *e,
or NULL if there is no such element. */
nsync_dll_element_ *nsync_dll_next_ (nsync_dll_list_ list, nsync_dll_element_ *e) {
nsync_dll_element_ *next = NULL;
if (e != list) {
next = e->next;
}
return (next);
}
/* Return a pointer to the previous element of list following *e,
or NULL if there is no such element. */
nsync_dll_element_ *nsync_dll_prev_ (nsync_dll_list_ list, nsync_dll_element_ *e) {
nsync_dll_element_ *prev = NULL;
if (e != list->next) {
prev = e->prev;
}
return (prev);
}