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/*
cc -g -c isofs_wrap.c
*/
/*
libisofs related functions of libisoburn.
Copyright 2007 Vreixo Formoso Lopes <metalpain2002@yahoo.es>
*/
#include <stdlib.h>
#include <string.h>
#include <assert.h>
#include <libburn/libburn.h>
#include <libisofs/libisofs.h>
#include "isoburn.h"
#include "libisoburn.h"
#define BP(a,b) [(b) - (a) + 1]
struct ecma119_pri_vol_desc
{
uint8_t vol_desc_type BP(1, 1);
uint8_t std_identifier BP(2, 6);
uint8_t vol_desc_version BP(7, 7);
uint8_t unused1 BP(8, 8);
uint8_t system_id BP(9, 40);
uint8_t volume_id BP(41, 72);
uint8_t unused2 BP(73, 80);
uint8_t vol_space_size BP(81, 88);
uint8_t unused3 BP(89, 120);
uint8_t vol_set_size BP(121, 124);
uint8_t vol_seq_number BP(125, 128);
uint8_t block_size BP(129, 132);
uint8_t path_table_size BP(133, 140);
uint8_t l_path_table_pos BP(141, 144);
uint8_t opt_l_path_table_pos BP(145, 148);
uint8_t m_path_table_pos BP(149, 152);
uint8_t opt_m_path_table_pos BP(153, 156);
uint8_t root_dir_record BP(157, 190);
uint8_t vol_set_id BP(191, 318);
uint8_t publisher_id BP(319, 446);
uint8_t data_prep_id BP(447, 574);
uint8_t application_id BP(575, 702);
uint8_t copyright_file_id BP(703, 739);
uint8_t abstract_file_id BP(740, 776);
uint8_t bibliographic_file_id BP(777, 813);
uint8_t vol_creation_time BP(814, 830);
uint8_t vol_modification_time BP(831, 847);
uint8_t vol_expiration_time BP(848, 864);
uint8_t vol_effective_time BP(865, 881);
uint8_t file_structure_version BP(882, 882);
uint8_t reserved1 BP(883, 883);
uint8_t app_use BP(884, 1395);
uint8_t reserved2 BP(1396, 2048);
};
static
uint32_t iso_read_lsb(const uint8_t *buf, int bytes)
{
int i;
uint32_t ret = 0;
for (i=0; i<bytes; i++) {
ret += ((uint32_t) buf[i]) << (i*8);
}
return ret;
}
/* API function. See libisoburn.h
*/
int isoburn_read_volset(struct burn_drive *d, struct isoburn_read_opts *read_opts,
struct iso_volset **volset)
{
int ret;
struct ecma119_read_opts ropts;
struct isoburn *o;
assert(d && read_opts && volset);
ret = isoburn_find_emulator(&o, d, 0);
if (ret < 0)
return 0;
if (!o) {
return -1;
}
if (o->fabricated_disc_status == BURN_DISC_BLANK) {
// FIXME construct an empty volset!!
*volset = NULL;
return 1;
}
ret = isoburn_disc_get_msc1(d, (int*) &ropts.block);
if (ret < 0)
return -2;
ropts.norock = read_opts->norock;
ropts.nojoliet = read_opts->nojoliet;
ropts.preferjoliet = read_opts->preferjoliet;
ropts.mode = read_opts->mode;
ropts.uid = read_opts->uid;
ropts.gid = read_opts->gid;
assert(o->src);
*volset = iso_volset_read(o->src, &ropts);
if (!(*volset))
return -3;
o->target_volset = *volset;
read_opts->hasRR = ropts.hasRR;
read_opts->hasJoliet = ropts.hasJoliet;
return 1;
}
/* API function. See libisoburn.h
*/
int isoburn_activate_session(struct burn_drive *drive)
{
int ret;
struct isoburn *o;
ret = isoburn_find_emulator(&o, drive, 0);
if (ret < 0)
return -1;
if (o->emulation_mode != 1)
return 1; /* don't need to activate session */
ret = burn_random_access_write(drive, 0, (char*)o->target_iso_head, 64*2048, 0);
return ret;
}
/** Allocate and initialize memory for libisofs related objects in
struct isoburn.
@param o A freshly created isoburn object with NULL pointers
@return <=0 error , 1 = success
*/
int isoburn_new_rwopts(struct isoburn *o)
{
struct ecma119_source_opts *wopts;
/* create and initialize new_wopts write options for new image */
wopts = calloc(1, sizeof(struct ecma119_source_opts));
if (!wopts)
return -1;
wopts->overwrite = o->target_iso_head;
o->new_wopts = wopts;
return 1;
}
/** Dispose memory objects created by isoburn_new_rwopts(). This function
expect that the pointers in struct isoburn might still be NULL, i.e.
that isoburn_new_rwopts() was not called before.
@return <=0 error , 1 = success
*/
int isoburn_free_rwopts(struct isoburn *o)
{
// FIXME I really don't like the data_source_free here.
// isoburn_drive_release() seems a better place
if (o->src)
data_source_free(o->src);
free(o->new_wopts);
return 1;
}
/** Initialize the emulation of multi-session on random access media.
The need for emulation is confirmed already.
@param o A freshly created isoburn object. isoburn_new_rwopts() was
already called, nevertheless.
@return <=0 error , 1 = success
*/
int isoburn_start_emulation(struct isoburn *o, int flag)
{
int ret, i;
off_t data_count;
struct burn_drive *drive;
struct ecma119_pri_vol_desc *pvm;
assert(o);
drive= o->drive;
/* we can assume 0 as start block for image */
// TODO what about ms? where we validate valid iso image in ms disc?
ret = burn_read_data(drive, (off_t) 0, (char*)o->target_iso_head,
sizeof(o->target_iso_head), &data_count, 0);
/* an error means an empty disc */
if (ret <= 0) {
o->fabricated_disc_status= BURN_DISC_BLANK;
return 1;
}
/* create and initialize the data source */
o->src = isoburn_data_source_new(o->drive);
if (!o->src)
return -1;
/* check first 64K. If 0's, the disc is treated as a blank disc, and thus
overwritten without extra check. */
i = sizeof(o->target_iso_head);
while (i && !o->target_iso_head[i-1])
--i;
if (!i) {
o->fabricated_disc_status= BURN_DISC_BLANK;
return 1;
}
pvm = (struct ecma119_pri_vol_desc *)(o->target_iso_head + 16 * 2048);
if (!strncmp((char*)pvm->std_identifier, "CD001", 5)) {
off_t size;
/* sanity check */
if (pvm->vol_desc_type[0] != 1 || pvm->vol_desc_version[0] != 1
|| pvm->file_structure_version[0] != 1 ) {
// TODO for now I treat this as a full disc
o->fabricated_disc_status= BURN_DISC_FULL;
return 1;
}
/* ok, PVM found, set size */
size = (off_t) iso_read_lsb(pvm->vol_space_size, 4);
size *= (off_t) 2048; /* block size in bytes */
isoburn_set_start_byte(o, size, 0);
o->fabricated_disc_status= BURN_DISC_APPENDABLE;
} else if (!strncmp((char*)pvm->std_identifier, "CDXX1", 5)) {
/* empty image */
isoburn_set_start_byte(o, (off_t) 0, 0);
o->fabricated_disc_status= BURN_DISC_BLANK;
} else {
/* treat any disc in an unknown format as full */
o->fabricated_disc_status= BURN_DISC_FULL;
}
return 1;
}
/** Alters and writes the first 64 kB of a "media" to invalidate
an ISO image. (It shall stay restorable by skilled humans, though).
The result shall especially keep libisoburn from accepting the media
image as ISO filesystem.
@param o A fully activated isoburn object. isoburn_start_emulation()
was already called.
@return <=0 error , 1 = success
*/
int isoburn_invalidate_iso(struct isoburn *o, int flag)
{
/*
* replace CD001 with CDXX1 in PVM.
* I think this is enought for invalidating an iso image
*/
strncpy((char*)o->target_iso_head + 16 * 2048 + 1, "CDXX1", 5);
return isoburn_activate_session(o->drive);
}