util/archive/archive.h

   1 /* SPDX-License-Identifier: GPL-2.0-only */
   2
   3 #ifndef __ARCHIVE_H
   4 #define __ARCHIVE_H
   5
   6 #include <stdint.h>
   7
   8 /*
   9  * Archive file layout:
  10  *
  11  *  +----------------------------------+
  12  *  |           root header            |
  13  *  +----------------------------------+
  14  *  |         file_header[0]           |
  15  *  +----------------------------------+
  16  *  |         file_header[1]           |
  17  *  +----------------------------------+
  18  *  |              ...                 |
  19  *  +----------------------------------+
  20  *  |         file_header[count-1]     |
  21  *  +----------------------------------+
  22  *  |         file(0) content          |
  23  *  +----------------------------------+
  24  *  |         file(1) content          |
  25  *  +----------------------------------+
  26  *  |              ...                 |
  27  *  +----------------------------------+
  28  *  |         file(count-1) content    |
  29  *  +----------------------------------+
  30  */
  31
  32 #define VERSION         0
  33 #define CBAR_MAGIC      "CBAR"
  34 #define NAME_LENGTH     32
  35
  36 /* Root header */
  37 struct directory {
  38         char magic[4];
  39         uint32_t version;       /* version of the header. little endian */
  40         uint32_t size;          /* total size of archive. little endian */
  41         uint32_t count;         /* number of files. little endian */
  42 };
  43
  44 /* File header */
  45 struct dentry {
  46         /* file name. null-terminated if shorter than NAME_LENGTH */
  47         char name[NAME_LENGTH];
  48         /* file offset from the root header. little endian */
  49         uint32_t offset;
  50         /* file size. little endian */
  51         uint32_t size;
  52 };
  53
  54 static inline struct dentry *get_first_dentry(const struct directory *dir)
  55 {
  56         return (struct dentry *)(dir + 1);
  57 }
  58
  59 static inline uint32_t get_first_offset(const struct directory *dir)
  60 {
  61         return sizeof(struct directory) + sizeof(struct dentry) * dir->count;
  62 }
  63
  64 #endif