xref: /freebsd/usr.bin/mkuzip/mkuz_fqueue.c (revision 243e928310d073338c5ec089f0dce238a80b9866)
1 /*
2  * Copyright (c) 2004-2016 Maxim Sobolev <sobomax@FreeBSD.org>
3  * All rights reserved.
4  *
5  * Redistribution and use in source and binary forms, with or without
6  * modification, are permitted provided that the following conditions
7  * are met:
8  * 1. Redistributions of source code must retain the above copyright
9  *    notice, this list of conditions and the following disclaimer.
10  * 2. Redistributions in binary form must reproduce the above copyright
11  *    notice, this list of conditions and the following disclaimer in the
12  *    documentation and/or other materials provided with the distribution.
13  *
14  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
15  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
16  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
17  * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
18  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
19  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
20  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
21  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
22  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
23  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
24  * SUCH DAMAGE.
25  */
26 
27 #include <sys/cdefs.h>
28 __FBSDID("$FreeBSD$");
29 
30 #include <err.h>
31 #include <pthread.h>
32 #include <stdint.h>
33 #include <stdlib.h>
34 
35 #if defined(MKUZ_DEBUG)
36 # include <assert.h>
37 #endif
38 
39 #include "mkuzip.h"
40 #include "mkuz_fqueue.h"
41 #include "mkuz_conveyor.h"
42 #include "mkuz_blk.h"
43 #include "mkuz_blk_chain.h"
44 
45 struct mkuz_fifo_queue *
46 mkuz_fqueue_ctor(int wakeup_len)
47 {
48     struct mkuz_fifo_queue *fqp;
49 
50     fqp = mkuz_safe_zmalloc(sizeof(struct mkuz_fifo_queue));
51     fqp->wakeup_len = wakeup_len;
52     if (pthread_mutex_init(&fqp->mtx, NULL) != 0) {
53         errx(1, "pthread_mutex_init() failed");
54     }
55     if (pthread_cond_init(&fqp->cvar, NULL) != 0) {
56         errx(1, "pthread_cond_init() failed");
57     }
58     return (fqp);
59 }
60 
61 void
62 mkuz_fqueue_enq(struct mkuz_fifo_queue *fqp, struct mkuz_blk *bp)
63 {
64     struct mkuz_bchain_link *ip;
65 
66     ip = mkuz_safe_zmalloc(sizeof(struct mkuz_bchain_link));
67     ip->this = bp;
68 
69     pthread_mutex_lock(&fqp->mtx);
70     if (fqp->first != NULL) {
71         fqp->first->prev = ip;
72     } else {
73         fqp->last = ip;
74     }
75     fqp->first = ip;
76     fqp->length += 1;
77     if (fqp->length >= fqp->wakeup_len) {
78         pthread_cond_signal(&fqp->cvar);
79     }
80     pthread_mutex_unlock(&fqp->mtx);
81 }
82 
83 #if defined(NOTYET)
84 int
85 mkuz_fqueue_enq_all(struct mkuz_fifo_queue *fqp, struct mkuz_bchain_link *cip_f,
86   struct mkuz_bchain_link *cip_l, int clen)
87 {
88     int rval;
89 
90     pthread_mutex_lock(&fqp->mtx);
91     if (fqp->first != NULL) {
92         fqp->first->prev = cip_l;
93     } else {
94         fqp->last = cip_l;
95     }
96     fqp->first = cip_f;
97     fqp->length += clen;
98     rval = fqp->length;
99     if (fqp->length >= fqp->wakeup_len) {
100         pthread_cond_signal(&fqp->cvar);
101     }
102     pthread_mutex_unlock(&fqp->mtx);
103     return (rval);
104 }
105 #endif
106 
107 static int
108 mkuz_fqueue_check(struct mkuz_fifo_queue *fqp, cmp_cb_t cmp_cb, void *cap)
109 {
110     struct mkuz_bchain_link *ip;
111 
112     for (ip = fqp->last; ip != NULL; ip = ip->prev) {
113         if (cmp_cb(ip->this, cap)) {
114             return (1);
115         }
116     }
117     return (0);
118 }
119 
120 struct mkuz_blk *
121 mkuz_fqueue_deq_when(struct mkuz_fifo_queue *fqp, cmp_cb_t cmp_cb, void *cap)
122 {
123     struct mkuz_bchain_link *ip, *newlast, *newfirst, *mip;
124     struct mkuz_blk *bp;
125 
126     pthread_mutex_lock(&fqp->mtx);
127     while (fqp->last == NULL || !mkuz_fqueue_check(fqp, cmp_cb, cap)) {
128         pthread_cond_wait(&fqp->cvar, &fqp->mtx);
129     }
130     if (cmp_cb(fqp->last->this, cap)) {
131         mip = fqp->last;
132         fqp->last = mip->prev;
133         if (fqp->last == NULL) {
134 #if defined(MKUZ_DEBUG)
135             assert(fqp->length == 1);
136 #endif
137             fqp->first = NULL;
138         }
139     } else {
140 #if defined(MKUZ_DEBUG)
141         assert(fqp->length > 1);
142 #endif
143         newfirst = newlast = fqp->last;
144         mip = NULL;
145         for (ip = fqp->last->prev; ip != NULL; ip = ip->prev) {
146             if (cmp_cb(ip->this, cap)) {
147                 mip = ip;
148                 continue;
149             }
150             newfirst->prev = ip;
151             newfirst = ip;
152         }
153         newfirst->prev = NULL;
154         fqp->first = newfirst;
155         fqp->last = newlast;
156     }
157     fqp->length -= 1;
158     pthread_mutex_unlock(&fqp->mtx);
159     bp = mip->this;
160     free(mip);
161 
162     return bp;
163 }
164 
165 struct mkuz_blk *
166 mkuz_fqueue_deq(struct mkuz_fifo_queue *fqp)
167 {
168     struct mkuz_bchain_link *ip;
169     struct mkuz_blk *bp;
170 
171     pthread_mutex_lock(&fqp->mtx);
172     while (fqp->last == NULL) {
173         pthread_cond_wait(&fqp->cvar, &fqp->mtx);
174     }
175 #if defined(MKUZ_DEBUG)
176     assert(fqp->length > 0);
177 #endif
178     ip = fqp->last;
179     fqp->last = ip->prev;
180     if (fqp->last == NULL) {
181 #if defined(MKUZ_DEBUG)
182         assert(fqp->length == 1);
183 #endif
184         fqp->first = NULL;
185     }
186     fqp->length -= 1;
187     pthread_mutex_unlock(&fqp->mtx);
188     bp = ip->this;
189     free(ip);
190 
191     return bp;
192 }
193 
194 #if defined(NOTYET)
195 struct mkuz_bchain_link *
196 mkuz_fqueue_deq_all(struct mkuz_fifo_queue *fqp, int *rclen)
197 {
198     struct mkuz_bchain_link *rchain;
199 
200     pthread_mutex_lock(&fqp->mtx);
201     while (fqp->last == NULL) {
202         pthread_cond_wait(&fqp->cvar, &fqp->mtx);
203     }
204 #if defined(MKUZ_DEBUG)
205     assert(fqp->length > 0);
206 #endif
207     rchain = fqp->last;
208     fqp->first = fqp->last = NULL;
209     *rclen = fqp->length;
210     fqp->length = 0;
211     pthread_mutex_unlock(&fqp->mtx);
212     return (rchain);
213 }
214 #endif
215