util/archive/archive.h

   1 /*
   2  * Copyright (C) 2015 The ChromiumOS Authors.  All rights reserved.
   3  *                 written by Daisuke Nojiri <dnojiri@chromium.org>
   4  *
   5  * This program is free software; you can redistribute it and/or modify
   6  * it under the terms of the GNU General Public License as published by
   7  * the Free Software Foundation; version 2 of the License.
   8  *
   9  * This program is distributed in the hope that it will be useful,
  10  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  11  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  12  * GNU General Public License for more details.
  13  */
  14
  15 #ifndef __ARCHIVE_H
  16 #define __ARCHIVE_H
  17
  18 #include <stdint.h>
  19
  20 /*
  21  * Archive file layout:
  22  *
  23  *  +----------------------------------+
  24  *  |           root header            |
  25  *  +----------------------------------+
  26  *  |         file_header[0]           |
  27  *  +----------------------------------+
  28  *  |         file_header[1]           |
  29  *  +----------------------------------+
  30  *  |              ...                 |
  31  *  +----------------------------------+
  32  *  |         file_header[count-1]     |
  33  *  +----------------------------------+
  34  *  |         file(0) content          |
  35  *  +----------------------------------+
  36  *  |         file(1) content          |
  37  *  +----------------------------------+
  38  *  |              ...                 |
  39  *  +----------------------------------+
  40  *  |         file(count-1) content    |
  41  *  +----------------------------------+
  42  */
  43
  44 #define VERSION         0
  45 #define CBAR_MAGIC      "CBAR"
  46 #define NAME_LENGTH     32
  47
  48 /* Root header */
  49 struct directory {
  50         char magic[4];
  51         uint32_t version;       /* version of the header. little endian */
  52         uint32_t size;          /* total size of archive. little endian */
  53         uint32_t count;         /* number of files. little endian */
  54 };
  55
  56 /* File header */
  57 struct dentry {
  58         /* file name. null-terminated if shorter than NAME_LENGTH */
  59         char name[NAME_LENGTH];
  60         /* file offset from the root header. little endian */
  61         uint32_t offset;
  62         /* file size. little endian */
  63         uint32_t size;
  64 };
  65
  66 static inline struct dentry *get_first_dentry(const struct directory *dir)
  67 {
  68         return (struct dentry *)(dir + 1);
  69 }
  70
  71 static inline uint32_t get_first_offset(const struct directory *dir)
  72 {
  73         return sizeof(struct directory) + sizeof(struct dentry) * dir->count;
  74 }
  75
  76 #endif