CoolPotOS/include/iso9660.h

#ifndef CRASHPOWEROS_ISO9660_H
#define CRASHPOWEROS_ISO9660_H

#define L9660_SEEK_END -1
#define L9660_SEEK_SET  0
#define L9660_SEEK_CUR +1

#include <stdint.h>
#include <stddef.h>
#include "common.h"

typedef enum {
    /*! Success! */
    L9660_OK = 0,
    /*! read_sector callback returned false */
    L9660_EIO,
    /*! file system is bad */
    L9660_EBADFS,
    /*! specified name does not exist */
    L9660_ENOENT,
    /*! attempted to open a non-file (e.g. a directory) as a file */
    L9660_ENOTFILE,
    /*! attempted to open a non-directory (e.g. a file) as a directory
     *  may be returned by l9660_openat if e.g. you pass path "a/b" and
     *  "a" is a file
     */
    L9660_ENOTDIR,
} l9660_status;

typedef struct {
    uint8_t le[2];
} l9660_luint16;
typedef struct {
    uint8_t be[2];
} l9660_buint16;
typedef struct {
    uint8_t le[2], be[2];
} l9660_duint16;
typedef struct {
    uint8_t le[4];
} l9660_luint32;
typedef struct {
    uint8_t be[4];
} l9660_buint32;
typedef struct {
    uint8_t le[4], be[4];
} l9660_duint32;

/* Descriptor time format */
typedef struct {
    char d[17];
} l9660_desctime;

/* File time format */
typedef struct {
    char d[7];
} l9660_filetime;

/* Directory entry */
typedef struct {
    uint8_t length;
    uint8_t xattr_length;
    l9660_duint32 sector;
    l9660_duint32 size;
    l9660_filetime time;
    uint8_t flags;
    uint8_t unit_size;
    uint8_t gap_size;
    l9660_duint16 vol_seq_number;
    uint8_t name_len;
    char name[/*name_len*/];
} l9660_dirent;

/* Volume descriptor header */
typedef struct {
    uint8_t type;
    char magic[5];
    uint8_t version;
} l9660_vdesc_header;

/* Primary volume descriptor */
typedef struct {
    l9660_vdesc_header hdr;
    char pad0[1];
    char system_id[32];
    char volume_id[32];
    char pad1[8];
    l9660_duint32 volume_space_size;
    char pad2[32];
    l9660_duint16 volume_set_size;
    l9660_duint16 volume_seq_number;
    l9660_duint16 logical_block_size;
    l9660_duint32 path_table_size;
    l9660_luint32 path_table_le;
    l9660_luint32 path_table_opt_le;
    l9660_buint32 path_table_be;
    l9660_buint32 path_table_opt_be;
    union {
        l9660_dirent root_dir_ent;
        char pad3[34];
    };
    char volume_set_id[128];
    char data_preparer_id[128];
    char app_id[128];
    char copyright_file[38];
    char abstract_file[36];
    char bibliography_file[37];
    l9660_desctime volume_created,
            volume_modified,
            volume_expires,
            volume_effective;
    uint8_t file_structure_version;
    char pad4[1];
    char app_reserved[512];
    char reserved[653];
} l9660_vdesc_primary;

/* A generic volume descriptor (i.e. 2048 bytes) */
typedef union {
    l9660_vdesc_header hdr;
    char _bits[2048];
} l9660_vdesc;

/* File system structure.
 * Stick this inside your own structure and cast/offset as appropriate to store
 * private data
 */
typedef struct l9660_fs {
#ifdef L9660_SINGLEBUFFER
    union {
        l9660_dirent    root_dir_ent;
        char            root_dir_pad[34];
    };
#else
    /* Sector buffer to hold the PVD */
    l9660_vdesc pvd;
#endif

    /* read_sector func */
    bool (*read_sector)(struct l9660_fs *fs, void *buf, uint32_t sector);
} l9660_fs;

typedef struct {
#ifndef L9660_SINGLEBUFFER
    /* single sector buffer */
    char buf[2048];
#endif
    l9660_fs *fs;
    uint32_t first_sector;
    uint32_t position;
    uint32_t length;
} l9660_file;

typedef struct {
    /* directories are mostly just files with special accessors, but we like type safetey */
    l9660_file file;
} l9660_dir;

uint32_t l9660_tell(l9660_file *f);
l9660_status l9660_read(l9660_file *f, void *buf, size_t size, size_t *read);
l9660_status l9660_seek(l9660_file *f, int whence, int32_t offset);
l9660_status l9660_openat(l9660_file *child, l9660_dir *parent, const char *name);
l9660_status l9660_readdir(l9660_dir *dir, l9660_dirent **pdirent);
l9660_status l9660_opendirat(l9660_dir *dir, l9660_dir *parent, const char *path);
l9660_status l9660_fs_open_root(l9660_dir *dir, l9660_fs *fs);
l9660_status l9660_openfs(l9660_fs *fs, bool (*read_sector)(l9660_fs *fs, void *buf, uint32_t sector,uint8_t disk_number),uint8_t disk_number);
void init_iso9660();

#endif