summaryrefslogtreecommitdiff
path: root/pr/include/private/pprmwait.h
blob: 4cc5492bbfcdf2854664ea6b7b4487a7a839ba9a (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
/* -*- Mode: C++; tab-width: 4; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
/* 
 * 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 Netscape are 
 * Copyright (C) 1998-2000 Netscape Communications Corporation.  All
 * Rights Reserved.
 * 
 * Contributor(s):
 * 
 * Alternatively, the contents of this file may be used under the
 * terms of the GNU General Public License Version 2 or later (the
 * "GPL"), in which case the provisions of the GPL are applicable 
 * instead of those above.  If you wish to allow use of your 
 * version of this file only under the terms of the GPL and not to
 * allow others to use your version of this file under the MPL,
 * indicate your decision by deleting the provisions above and
 * replace them with the notice and other provisions required by
 * the GPL.  If you do not delete the provisions above, a recipient
 * may use your version of this file under either the MPL or the
 * GPL.
 */

#if defined(_PPRMWAIT_H)
#else
#define _PPRMWAIT_H

#include "prlock.h"
#include "prcvar.h"
#include "prclist.h"
#include "prthread.h"

#define MAX_POLLING_INTERVAL 100
#define _PR_POLL_COUNT_FUDGE 64
#define MAX_POLLING_INTERVAL 100
#define _PR_DEFAULT_HASH_LENGTH 59

/*
 * Our hash table resolves collisions by open addressing with
 * double hashing.  See Cormen, Leiserson, and Rivest,
 * Introduction to Algorithms, p. 232, The MIT Press, 1990.
 */

#define _MW_HASH(a, m) ((((PRUptrdiff)(a) >> 4) ^ ((PRUptrdiff)(a) >> 10)) % (m))
#define _MW_HASH2(a, m) (1 + ((((PRUptrdiff)(a) >> 4) ^ ((PRUptrdiff)(a) >> 10)) % (m - 2)))
#define _MW_ABORTED(_rv) \
    ((PR_FAILURE == (_rv)) && (PR_PENDING_INTERRUPT_ERROR == PR_GetError()))

typedef enum {_prmw_success, _prmw_rehash, _prmw_error} _PR_HashStory;

typedef struct _PRWaiterHash
{
    PRUint16 count;             /* current number in hash table */
    PRUint16 length;            /* current size of the hash table */
    PRRecvWait *recv_wait;      /* hash table of receive wait objects */
} _PRWaiterHash;

typedef enum {_prmw_running, _prmw_stopping, _prmw_stopped} PRMWGroupState;

struct PRWaitGroup
{
    PRCList group_link;         /* all groups are linked to each other */
    PRCList io_ready;           /* list of I/O requests that are ready */
    PRMWGroupState state;       /* state of this group (so we can shut down) */

    PRLock *ml;                 /* lock for synchronizing this wait group */
    PRCondVar *io_taken;        /* calling threads notify when they take I/O */
    PRCondVar *io_complete;     /* calling threads wait here for completions */
    PRCondVar *new_business;    /* polling thread waits here more work */
    PRCondVar *mw_manage;       /* used to manage group lists */
    PRThread* poller;           /* thread that's actually doing the poll() */
    PRUint16 waiting_threads;   /* number of threads waiting for recv */
    PRUint16 polling_count;     /* number of elements in the polling list */
    PRUint32 p_timestamp;       /* pseudo-time group had element removed */
    PRPollDesc *polling_list;   /* list poller builds for polling */
    PRIntervalTime last_poll;   /* last time we polled */
    _PRWaiterHash *waiter;      /* pointer to hash table of wait receive objects */

#ifdef WINNT
    /*
     * On NT, idle threads are responsible for getting completed i/o.
     * They need to add completed i/o to the io_ready list.  Since
     * idle threads cannot use nspr locks, we have to use an md lock
     * to protect the io_ready list.
     */
    _MDLock mdlock;             /* protect io_ready, waiter, and wait_list */
    PRCList wait_list;          /* used in place of io_complete.  reuse
                                 * waitQLinks in the PRThread structure. */
#endif /* WINNT */
};

/**********************************************************************
***********************************************************************
******************** Wait group enumerations **************************
***********************************************************************
**********************************************************************/
typedef struct _PRGlobalState
{
    PRCList group_list;         /* master of the group list */
    PRWaitGroup *group;         /* the default (NULL) group */
} _PRGlobalState;

#ifdef WINNT
extern PRStatus NT_HashRemoveInternal(PRWaitGroup *group, PRFileDesc *fd);
#endif

typedef enum {_PR_ENUM_UNSEALED=0, _PR_ENUM_SEALED=0x0eadface} _PREnumSeal;

struct PRMWaitEnumerator
{
    PRWaitGroup *group;       /* group this enumerator is bound to */
    PRThread *thread;               /* thread in midst of an enumeration */
    _PREnumSeal seal;               /* trying to detect deleted objects */
    PRUint32 p_timestamp;           /* when enumeration was (re)started */
    PRRecvWait **waiter;            /* pointer into hash table */
    PRUintn index;                  /* position in hash table */
    void *pad[4];                   /* some room to grow */
};

#endif /* defined(_PPRMWAIT_H) */

/* pprmwait.h */