1 #ifndef CACHES_QUEUES_LISTS_H
2 #define CACHES_QUEUES_LISTS_H
3 /*
4  * Create a squashfs filesystem.  This is a highly compressed read only
5  * filesystem.
6  *
7  * Copyright (c) 2013, 2014
8  * Phillip Lougher <phillip@squashfs.org.uk>
9  *
10  * This program is free software; you can redistribute it and/or
11  * modify it under the terms of the GNU General Public License
12  * as published by the Free Software Foundation; either version 2,
13  * or (at your option) any later version.
14  *
15  * This program is distributed in the hope that it will be useful,
16  * but WITHOUT ANY WARRANTY; without even the implied warranty of
17  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
18  * GNU General Public License for more details.
19  *
20  * You should have received a copy of the GNU General Public License
21  * along with this program; if not, write to the Free Software
22  * Foundation, 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
23  *
24  * caches-queues-lists.h
25  */
26 
27 #define INSERT_LIST(NAME, TYPE) \
28 void insert_##NAME##_list(TYPE **list, TYPE *entry) { \
29 	if(*list) { \
30 		entry->NAME##_next = *list; \
31 		entry->NAME##_prev = (*list)->NAME##_prev; \
32 		(*list)->NAME##_prev->NAME##_next = entry; \
33 		(*list)->NAME##_prev = entry; \
34 	} else { \
35 		*list = entry; \
36 		entry->NAME##_prev = entry->NAME##_next = entry; \
37 	} \
38 }
39 
40 
41 #define REMOVE_LIST(NAME, TYPE) \
42 void remove_##NAME##_list(TYPE **list, TYPE *entry) { \
43 	if(entry->NAME##_prev == entry && entry->NAME##_next == entry) { \
44 		/* only this entry in the list */ \
45 		*list = NULL; \
46 	} else if(entry->NAME##_prev != NULL && entry->NAME##_next != NULL) { \
47 		/* more than one entry in the list */ \
48 		entry->NAME##_next->NAME##_prev = entry->NAME##_prev; \
49 		entry->NAME##_prev->NAME##_next = entry->NAME##_next; \
50 		if(*list == entry) \
51 			*list = entry->NAME##_next; \
52 	} \
53 	entry->NAME##_prev = entry->NAME##_next = NULL; \
54 }
55 
56 
57 #define INSERT_HASH_TABLE(NAME, TYPE, HASH_FUNCTION, FIELD, LINK) \
58 void insert_##NAME##_hash_table(TYPE *container, struct file_buffer *entry) \
59 { \
60 	int hash = HASH_FUNCTION(entry->FIELD); \
61 \
62 	entry->LINK##_next = container->hash_table[hash]; \
63 	container->hash_table[hash] = entry; \
64 	entry->LINK##_prev = NULL; \
65 	if(entry->LINK##_next) \
66 		entry->LINK##_next->LINK##_prev = entry; \
67 }
68 
69 
70 #define REMOVE_HASH_TABLE(NAME, TYPE, HASH_FUNCTION, FIELD, LINK) \
71 void remove_##NAME##_hash_table(TYPE *container, struct file_buffer *entry) \
72 { \
73 	if(entry->LINK##_prev) \
74 		entry->LINK##_prev->LINK##_next = entry->LINK##_next; \
75 	else \
76 		container->hash_table[HASH_FUNCTION(entry->FIELD)] = \
77 			entry->LINK##_next; \
78 	if(entry->LINK##_next) \
79 		entry->LINK##_next->LINK##_prev = entry->LINK##_prev; \
80 \
81 	entry->LINK##_prev = entry->LINK##_next = NULL; \
82 }
83 
84 #define HASH_SIZE 65536
85 #define CALCULATE_HASH(n) ((n) & 0xffff)
86 
87 
88 /* struct describing a cache entry passed between threads */
89 struct file_buffer {
90 	union {
91 		long long index;
92 		long long sequence;
93 	};
94 	long long file_size;
95 	union {
96 		long long block;
97 		unsigned short checksum;
98 	};
99 	struct cache *cache;
100 	union {
101 		struct file_info *dupl_start;
102 		struct file_buffer *hash_next;
103 	};
104 	union {
105 		int duplicate;
106 		struct file_buffer *hash_prev;
107 	};
108 	union {
109 		struct {
110 			struct file_buffer *free_next;
111 			struct file_buffer *free_prev;
112 		};
113 		struct {
114 			struct file_buffer *seq_next;
115 			struct file_buffer *seq_prev;
116 		};
117 	};
118 	int size;
119 	int c_byte;
120 	char used;
121 	char fragment;
122 	char error;
123 	char locked;
124 	char wait_on_unlock;
125 	char noD;
126 	char data[0];
127 };
128 
129 
130 /* struct describing queues used to pass data between threads */
131 struct queue {
132 	int			size;
133 	int			readp;
134 	int			writep;
135 	pthread_mutex_t		mutex;
136 	pthread_cond_t		empty;
137 	pthread_cond_t		full;
138 	void			**data;
139 };
140 
141 
142 /*
143  * struct describing seq_queues used to pass data between the read
144  * thread and the deflate and main threads
145  */
146 struct seq_queue {
147 	int			fragment_count;
148 	int			block_count;
149 	struct file_buffer	*hash_table[HASH_SIZE];
150 	pthread_mutex_t		mutex;
151 	pthread_cond_t		wait;
152 };
153 
154 
155 /* Cache status struct.  Caches are used to keep
156   track of memory buffers passed between different threads */
157 struct cache {
158 	int	max_buffers;
159 	int	count;
160 	int	buffer_size;
161 	int	noshrink_lookup;
162 	int	first_freelist;
163 	union {
164 		int	used;
165 		int	max_count;
166 	};
167 	pthread_mutex_t	mutex;
168 	pthread_cond_t wait_for_free;
169 	pthread_cond_t wait_for_unlock;
170 	struct file_buffer *free_list;
171 	struct file_buffer *hash_table[HASH_SIZE];
172 };
173 
174 
175 extern struct queue *queue_init(int);
176 extern void queue_put(struct queue *, void *);
177 extern void *queue_get(struct queue *);
178 extern int queue_empty(struct queue *);
179 extern void queue_flush(struct queue *);
180 extern void dump_queue(struct queue *);
181 extern struct seq_queue *seq_queue_init();
182 extern void seq_queue_put(struct seq_queue *, struct file_buffer *);
183 extern void dump_seq_queue(struct seq_queue *, int);
184 extern struct file_buffer *seq_queue_get(struct seq_queue *);
185 extern void seq_queue_flush(struct seq_queue *);
186 extern struct cache *cache_init(int, int, int, int);
187 extern struct file_buffer *cache_lookup(struct cache *, long long);
188 extern struct file_buffer *cache_get(struct cache *, long long);
189 extern struct file_buffer *cache_get_nohash(struct cache *);
190 extern void cache_hash(struct file_buffer *, long long);
191 extern void cache_block_put(struct file_buffer *);
192 extern void dump_cache(struct cache *);
193 extern struct file_buffer *cache_get_nowait(struct cache *, long long);
194 extern struct file_buffer *cache_lookup_nowait(struct cache *, long long,
195 	char *);
196 extern void cache_wait_unlock(struct file_buffer *);
197 extern void cache_unlock(struct file_buffer *);
198 
199 extern int first_freelist;
200 #endif
201