libisofs/libisofs/rockridge.h

350 lines
9.8 KiB
C

/*
* Copyright (c) 2007 Vreixo Formoso
* Copyright (c) 2007 Mario Danic
* Copyright (c) 2009 Thomas Schmitt
*
* This file is part of the libisofs project; you can redistribute it and/or
* modify it under the terms of the GNU General Public License version 2
* or later as published by the Free Software Foundation.
* See COPYING file for details.
*/
/**
* This header defines the functions and structures needed to add RockRidge
* extensions to an ISO image. It also handles AAIP and zisofs extensions.
*
* References:
*
* - SUSP (IEEE 1281).
* System Use Sharing Protocol, draft standard version 1.12.
* See ftp://ftp.ymi.com/pub/rockridge/susp112.ps
*
* - RRIP (IEEE 1282)
* Rock Ridge Interchange Protocol, Draft Standard version 1.12.
* See ftp://ftp.ymi.com/pub/rockridge/rrip112.ps
*
* - ECMA-119 (ISO-9660)
* Volume and File Structure of CDROM for Information Interchange. See
* http://www.ecma-international.org/publications/files/ECMA-ST/Ecma-119.pdf
*
* - AAIP
* Arbitrary Attribute Interchange Protocol. See doc/susp_aaip_2_0.txt
*
* - zisofs
* Blockwise compression of data file content with transparent read support
* in the Linux kernel. See doc/zisofs_format.txt
*
*/
#ifndef LIBISO_ROCKRIDGE_H
#define LIBISO_ROCKRIDGE_H
#include "ecma119.h"
#define SUSP_SIG(entry, a, b) ((entry->sig[0] == a) && (entry->sig[1] == b))
/**
* This contains the information about the System Use Fields (SUSP, 4.1),
* that will be written in the System Use Areas, both in the ISO directory
* record System Use field (ECMA-119, 9.1.13) or in a Continuation Area as
* defined by SUSP.
*/
struct susp_info
{
/** Number of SUSP fields in the System Use field */
size_t n_susp_fields;
uint8_t **susp_fields;
/** Length of the part of the SUSP area that fits in the dirent. */
int suf_len;
/** Length of the part of the SUSP area that will go in a CE area. */
uint32_t ce_block;
uint32_t ce_len;
size_t n_ce_susp_fields;
uint8_t **ce_susp_fields;
};
/* SUSP 5.1 */
struct susp_CE {
uint8_t block[8];
uint8_t offset[8];
uint8_t len[8];
};
/* SUSP 5.3 */
struct susp_SP {
uint8_t be[1];
uint8_t ef[1];
uint8_t len_skp[1];
};
/* SUSP 5.5 */
struct susp_ER {
uint8_t len_id[1];
uint8_t len_des[1];
uint8_t len_src[1];
uint8_t ext_ver[1];
uint8_t ext_id[1]; /*< up to len_id bytes */
/* ext_des, ext_src */
};
/** POSIX file attributes (RRIP, 4.1.1) */
struct rr_PX {
uint8_t mode[8];
uint8_t links[8];
uint8_t uid[8];
uint8_t gid[8];
uint8_t serial[8];
};
/** Time stamps for a file (RRIP, 4.1.6) */
struct rr_TF {
uint8_t flags[1];
uint8_t t_stamps[1];
};
/** Info for character and block device (RRIP, 4.1.2) */
struct rr_PN {
uint8_t high[8];
uint8_t low[8];
};
/** Alternate name (RRIP, 4.1.4) */
struct rr_NM {
uint8_t flags[1];
uint8_t name[1];
};
/** Link for a relocated directory (RRIP, 4.1.5.1) */
struct rr_CL {
uint8_t child_loc[8];
};
/** Sim link (RRIP, 4.1.3) */
struct rr_SL {
uint8_t flags[1];
uint8_t comps[1];
};
/** Outdated Arbitrary Attribute (AAIP, see doc/susp_aaip_1_0.txt)
* It collided with pre-SUSP Apple AA field.
*/
struct aaip_AA {
uint8_t flags[1];
uint8_t comps[1];
};
/** Arbitrary Attribute (AAIP, see doc/susp_aaip_2_0.txt) */
struct aaip_AL {
uint8_t flags[1];
uint8_t comps[1];
};
/** zisofs entry (see doc/zisofs_format.txt) */
struct zisofs_ZF {
uint8_t parameters[1]; /* begins with BP 5 */
};
/**
* Struct for a SUSP System User Entry (SUSP, 4.1)
*/
struct susp_sys_user_entry
{
uint8_t sig[2];
uint8_t len_sue[1];
uint8_t version[1];
union {
struct susp_CE CE;
struct susp_SP SP;
struct susp_ER ER;
struct rr_PX PX;
struct rr_TF TF;
struct rr_PN PN;
struct rr_NM NM;
struct rr_CL CL;
struct rr_SL SL;
struct aaip_AA AA;
struct aaip_AL AL;
struct zisofs_ZF ZF;
} data; /* 5 to 4+len_sue */
};
/**
* Compute the length needed for write all RR and SUSP entries for a given
* node.
*
* @param type
* 0 normal entry, 1 "." entry for that node (it is a dir), 2 ".."
* for that node (i.e., it will refer to the parent)
* @param space
* Available space in the System Use Area for the directory record.
* @param ce
* Will be filled with the space needed in a CE
* @return
* The size needed for the RR entries in the System Use Area
*/
size_t rrip_calc_len(Ecma119Image *t, Ecma119Node *n, int type, size_t space,
size_t *ce);
/**
* Fill a struct susp_info with the RR/SUSP entries needed for a given
* node.
*
* @param type
* 0 normal entry, 1 "." entry for that node (it is a dir), 2 ".."
* for that node (i.e., it will refer to the parent)
* @param space
* Available space in the System Use Area for the directory record.
* @param info
* Pointer to the struct susp_info where the entries will be stored.
* If some entries need to go to a Continuation Area, they will be added
* to the existing ce_susp_fields, and ce_len will be incremented
* propertly. Please ensure ce_block is initialized propertly.
* @return
* 1 success, < 0 error
*/
int rrip_get_susp_fields(Ecma119Image *t, Ecma119Node *n, int type,
size_t space, struct susp_info *info);
/**
* Write the given SUSP fields into buf. Note that Continuation Area
* fields are not written.
* If info does not contain any SUSP entry this function just return.
* After written, the info susp_fields array will be freed, and the counters
* updated propertly.
*/
void rrip_write_susp_fields(Ecma119Image *t, struct susp_info *info,
uint8_t *buf);
/**
* Write the Continuation Area entries for the given struct susp_info, using
* the iso_write() function.
* After written, the ce_susp_fields array will be freed.
*/
int rrip_write_ce_fields(Ecma119Image *t, struct susp_info *info);
/**
* The SUSP iterator is used to iterate over the System User Entries
* of a ECMA-168 directory record.
* It takes care about Continuation Areas, handles the end of the different
* system user entries and skip padding areas. Thus, using an iteration
* we are accessing just to the meaning entries.
*/
typedef struct susp_iterator SuspIterator;
SuspIterator *
susp_iter_new(IsoDataSource *src, struct ecma119_dir_record *record,
uint8_t len_skp, int msgid);
/**
* Get the next SUSP System User Entry using given iterator.
*
* @param sue
* Pointer to the next susp entry. It refers to an internal buffer and
* it's not guaranteed to be allocated after calling susp_iter_next()
* again. Thus, if you need to keep some entry you have to do a copy.
* @return
* 1 on success, 0 if no more entries, < 0 error
*/
int susp_iter_next(SuspIterator *iter, struct susp_sys_user_entry **sue);
/**
* Free a given susp iterator.
*/
void susp_iter_free(SuspIterator *iter);
/**
* Fills a struct stat with the values of a Rock Ridge PX entry (RRIP, 4.1.1).
*
* @return
* < 0 on error
* 1 on success with no inode number,
* 2 on success with inode number,
*/
int read_rr_PX(struct susp_sys_user_entry *px, struct stat *st);
/**
* Fills a struct stat with the values of a Rock Ridge TF entry (RRIP, 4.1.6)
*
* @return
* 1 on success, < 0 on error
*/
int read_rr_TF(struct susp_sys_user_entry *tf, struct stat *st);
/**
* Read a RR NM entry (RRIP, 4.1.4), and appends the name stored there to
* the given name. You can pass a pointer to NULL as name.
*
* @return
* 1 on success, < 0 on error
*/
int read_rr_NM(struct susp_sys_user_entry *nm, char **name, int *cont);
/**
* Read a SL RR entry (RRIP, 4.1.3), checking if the destination continues.
*
* @param cont
* 0 not continue, 1 continue, 2 continue component
* @return
* 1 on success, < 0 on error
*/
int read_rr_SL(struct susp_sys_user_entry *sl, char **dest, int *cont);
/**
* Fills a struct stat with the values of a Rock Ridge PN entry (RRIP, 4.1.2).
*
* @return
* 1 on success, < 0 on error
*/
int read_rr_PN(struct susp_sys_user_entry *pn, struct stat *st);
/**
* Collects the AAIP field string from single AAIP fields.
* (see doc/susp_aaip_1_0.txt)
* @param aa_string Storage location of the emerging string.
* Begin with *aa_string == NULL, or own malloc() storage.
* @param aa_size Current allocated size of aa_string.
* Begin with *aa_size == 0, or own storage size.
* @param aa_len Current occupied size of aa_string.
* Begin with *aa_len == 0
* @param prev_field Returns the index of start of the previous field
* in the string.
* @param is_done The current completion state of the AAIP field string.
* Fields will be ignored as soon as it is 1.
* Begin with *is_done == 0
* @param flag Unused yet. Submit 0.
* @return
* 1 on success, < 0 on error
*/
int read_aaip_AA(struct susp_sys_user_entry *sue,
unsigned char **aa_string, size_t *aa_size, size_t *aa_len,
size_t *prev_field, int *is_done, int flag);
/**
* Collects the AAIP field string from single AL fields.
* (see doc/susp_aaip_2_0.txt)
*/
int read_aaip_AL(struct susp_sys_user_entry *sue,
unsigned char **aa_string, size_t *aa_size, size_t *aa_len,
size_t *prev_field, int *is_done, int flag);
/**
* Reads the zisofs parameters from a ZF field (see doc/zisofs_format.txt).
*
* @return
* 1 on success, < 0 on error
*/
int read_zisofs_ZF(struct susp_sys_user_entry *zf, uint8_t algorithm[2],
uint8_t *header_size_div4, uint8_t *block_size_log2,
uint32_t *uncompressed_size, int flag);
#endif /* LIBISO_ROCKRIDGE_H */