SQUASHFS/squashfs-tools-4.4/squashfs-tools/compressor.h

   1 #ifndef COMPRESSOR_H
   2 #define COMPRESSOR_H
   3 /*
   4  *
   5  * Copyright (c) 2009, 2010, 2011, 2012, 2013, 2014
   6  * Phillip Lougher <phillip@squashfs.org.uk>
   7  *
   8  * This program is free software; you can redistribute it and/or
   9  * modify it under the terms of the GNU General Public License
  10  * as published by the Free Software Foundation; either version 2,
  11  * or (at your option) any later version.
  12  *
  13  * This program is distributed in the hope that it will be useful,
  14  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  15  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  16  * GNU General Public License for more details.
  17  *
  18  * You should have received a copy of the GNU General Public License
  19  * along with this program; if not, write to the Free Software
  20  * Foundation, 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
  21  *
  22  * compressor.h
  23  */
  24
  25 struct compressor {
  26         int id;
  27         char *name;
  28         int supported;
  29         int (*init)(void **, int, int);
  30         int (*compress)(void *, void *, void *, int, int, int *);
  31         int (*uncompress)(void *, void *, int, int, int *);
  32         int (*options)(char **, int);
  33         int (*options_post)(int);
  34         void *(*dump_options)(int, int *);
  35         int (*extract_options)(int, void *, int);
  36         int (*check_options)(int, void *, int);
  37         void (*display_options)(void *, int);
  38         void (*usage)();
  39 };
  40
  41 extern struct compressor *lookup_compressor(char *);
  42 extern struct compressor *lookup_compressor_id(int);
  43 extern void display_compressors(char *, char *);
  44 extern void display_compressor_usage(char *);
  45
  46 static inline int compressor_init(struct compressor *comp, void **stream,
  47         int block_size, int datablock)
  48 {
  49         if(comp->init == NULL)
  50                 return 0;
  51         return comp->init(stream, block_size, datablock);
  52 }
  53
  54
  55 static inline int compressor_compress(struct compressor *comp, void *strm,
  56         void *dest, void *src, int size, int block_size, int *error)
  57 {
  58         return comp->compress(strm, dest, src, size, block_size, error);
  59 }
  60
  61
  62 static inline int compressor_uncompress(struct compressor *comp, void *dest,
  63         void *src, int size, int block_size, int *error)
  64 {
  65         return comp->uncompress(dest, src, size, block_size, error);
  66 }
  67
  68
  69 /*
  70  * For the following functions please see the lzo, lz4 or xz
  71  * compressors for commented examples of how they are used.
  72  */
  73 static inline int compressor_options(struct compressor *comp, char *argv[],
  74         int argc)
  75 {
  76         if(comp->options == NULL)
  77                 return -1;
  78
  79         return comp->options(argv, argc);
  80 }
  81
  82
  83 static inline int compressor_options_post(struct compressor *comp, int block_size)
  84 {
  85         if(comp->options_post == NULL)
  86                 return 0;
  87         return comp->options_post(block_size);
  88 }
  89
  90
  91 static inline void *compressor_dump_options(struct compressor *comp,
  92         int block_size, int *size)
  93 {
  94         if(comp->dump_options == NULL)
  95                 return NULL;
  96         return comp->dump_options(block_size, size);
  97 }
  98
  99
 100 static inline int compressor_extract_options(struct compressor *comp,
 101         int block_size, void *buffer, int size)
 102 {
 103         if(comp->extract_options == NULL)
 104                 return size ? -1 : 0;
 105         return comp->extract_options(block_size, buffer, size);
 106 }
 107
 108
 109 static inline int compressor_check_options(struct compressor *comp,
 110         int block_size, void *buffer, int size)
 111 {
 112         if(comp->check_options == NULL)
 113                 return 0;
 114         return comp->check_options(block_size, buffer, size);
 115 }
 116
 117
 118 static inline void compressor_display_options(struct compressor *comp,
 119         void *buffer, int size)
 120 {
 121         if(comp->display_options != NULL)
 122                 comp->display_options(buffer, size);
 123 }
 124 #endif