libburnia/libisofs-legacy
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Split enumerate_common() into logic-layer, command-layer, transport-layer

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This commit is contained in:
Thomas Schmitt 2006-10-21 18:51:35 +00:00
parent 6f0643b7cf
commit e5ed5f1856
13 changed files with 510 additions and 111 deletions
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2
cdrskin/cdrskin_timestamp.h
View File

@ -1 +1 @@
#define Cdrskin_timestamP "2006.10.21.103653"
#define Cdrskin_timestamP "2006.10.21.185102"

60
libburn/drive.c
View File

@ -33,6 +33,16 @@ extern struct libdax_msgs *libdax_messenger;
static struct burn_drive drive_array[255];
static int drivetop = -1;
/* ts A61021 : the unspecific part of sg.c:enumerate_common()
*/
int burn_setup_drive(struct burn_drive *d, char *fname)
{
d->devname = burn_strdup(fname);
memset(&d->params, 0, sizeof(struct params));
d->released = 1;
d->status = BURN_DISC_UNREADY;
return 1;
}
/* ts A60904 : ticket 62, contribution by elmom */
/* splitting former burn_drive_free() (which freed all, into two calls) */
@ -65,21 +75,8 @@ void burn_drive_free_all(void)
/* ts A60822 */
int burn_drive_is_open(struct burn_drive *d)
{
#if defined(__FreeBSD__)
if (d->cam == NULL)
return 0;
#else /* __FreeBSD__ */
/* a bit more detailed case distinction than needed */
if (d->fd == -1337)
return 0;
if (d->fd < 0)
return 0;
#endif /* ! __FreeBSD__ */
return 1;
/* ts A61021 : moved decision to sg.c */
return d->drive_is_open(d);
}
@ -280,6 +277,39 @@ int burn_drive_unregister(struct burn_drive *d)
}
/* ts A61021 : after-setup activities from sg.c:enumerate_common()
*/
struct burn_drive *burn_drive_finish_enum(struct burn_drive *d)
{
struct burn_drive *t;
/* ts A60821
<<< debug: for tracing calls which might use open drive fds */
int mmc_function_spy(char * text);
t = burn_drive_register(d);
/* ts A60821 */
mmc_function_spy("enumerate_common : -------- doing grab");
/* try to get the drive info */
if (t->grab(t)) {
burn_print(2, "getting drive info\n");
t->getcaps(t);
t->unlock(t);
t->released = 1;
} else {
burn_print(2, "unable to grab new located drive\n");
burn_drive_unregister(t);
t = NULL;
}
/* ts A60821 */
mmc_function_spy("enumerate_common : ----- would release ");
return t;
}
void burn_drive_release(struct burn_drive *d, int le)
{
if (d->released) {

9
libburn/drive.h
View File

@ -61,4 +61,13 @@ int burn_drive_is_occupied(struct burn_drive *d);
int burn_drive_forget(struct burn_drive *d, int force);
int burn_drive_convert_fs_adr_sub(char *path, char adr[], int *rec_count);
/* ts A61021 : the unspecific part of sg.c:enumerate_common()
*/
int burn_setup_drive(struct burn_drive *d, char *fname);
/* ts A61021 : after-setup activities from sg.c:enumerate_common()
*/
struct burn_drive *burn_drive_finish_enum(struct burn_drive *d);
#endif /* __DRIVE */

24
libburn/mmc.c
View File

@ -757,3 +757,27 @@ void mmc_sync_cache(struct burn_drive *d)
c.dir = NO_TRANSFER;
d->issue_command(d, &c);
}
/* ts A61021 : the mmc specific part of sg.c:enumerate_common()
*/
int mmc_setup_drive(struct burn_drive *d)
{
d->read_atip = mmc_read_atip;
d->read_toc = mmc_read_toc;
d->write = mmc_write;
d->erase = mmc_erase;
d->read_sectors = mmc_read_sectors;
d->perform_opc = mmc_perform_opc;
d->set_speed = mmc_set_speed;
d->send_cue_sheet = mmc_send_cue_sheet;
d->sync_cache = mmc_sync_cache;
d->get_nwa = mmc_get_nwa;
d->close_disc = mmc_close_disc;
d->close_session = mmc_close_session;
/* ts A61020 */
d->start_lba= -2000000000;
d->end_lba= -2000000000;
return 1;
}

5
libburn/mmc.h
View File

@ -39,4 +39,9 @@ void mmc_perform_opc(struct burn_drive *);
void mmc_get_configuration(struct burn_drive *);
int mmc_get_nwa(struct burn_drive *);
void mmc_send_cue_sheet(struct burn_drive *, struct cue_sheet *);
/* ts A61021 : the mmc specific part of sg.c:enumerate_common()
*/
int mmc_setup_drive(struct burn_drive *d);
#endif /*__MMC*/

10
libburn/sbc.c
View File

@ -36,3 +36,13 @@ void sbc_eject(struct burn_drive *d)
c.dir = NO_TRANSFER;
d->issue_command(d, &c);
}
/* ts A61021 : the sbc specific part of sg.c:enumerate_common()
*/
int sbc_setup_drive(struct burn_drive *d)
{
d->eject = sbc_eject;
d->load = sbc_load;
return 1;
}

4
libburn/sbc.h
View File

@ -8,4 +8,8 @@ struct burn_drive;
void sbc_load(struct burn_drive *);
void sbc_eject(struct burn_drive *);
/* ts A61021 : the sbc specific part of sg.c:enumerate_common()
*/
int sbc_setup_drive(struct burn_drive *d);
#endif /* __SBC */

320
libburn/sg-freebsd.c
View File

@ -1,5 +1,21 @@
/* -*- indent-tabs-mode: t; tab-width: 8; c-basic-offset: 8; -*- */
/* >>> ts A61021 : for testing the new arrangement of code
please outcomment these defines : */
/* Keeps alive old enumerate_common(). New version delegates much work
to methods in drive, mmc, spc, and sbc .
*/
#define Scsi_freebsd_make_own_enumeratE 1
/* Keeps alive old sg_enumerate(). New version delegates most work to
sg_give_next_adr().
*/
#define Scsi_freebsd_old_sg_enumeratE 1
#include <assert.h>
#include <errno.h>
#include <unistd.h>
@ -37,33 +53,17 @@ static void enumerate_common(char *fname, int bus_no, int host_no,
/* ts A51221 */
int burn_drive_is_banned(char *device_address);
/* ts A60813 : storage objects are in libburn/init.c
wether to use O_EXCL
wether to use O_NOBLOCK with open(2) on devices
wether to take O_EXCL rejection as fatal error */
extern int burn_sg_open_o_excl;
extern int burn_sg_open_o_nonblock;
extern int burn_sg_open_abort_busy;
/* ts A60821
<<< debug: for tracing calls which might use open drive fds */
int mmc_function_spy(char * text);
/** Returns the next index number and the next enumerated drive address.
@param idx An opaque handle. Make no own theories about it.
@param adr Takes the reply
@param adr_size Gives maximum size of reply including final 0
@param initialize 1 = start new,
0 = continue, use no other values for now
-1 = finish
@return 1 = reply is a valid address , 0 = no further address available
-1 = severe error (e.g. adr_size too small)
*/
#ifdef Scsi_freebsd_old_sg_enumeratE
int sg_give_next_adr(burn_drive_enumerator_t *idx,
char adr[], int adr_size, int initialize)
{
return (0);
}
@ -78,6 +78,208 @@ int sg_obtain_scsi_adr(char *path, int *bus_no, int *host_no, int *channel_no,
return (0);
}
#else /* Scsi_freebsd_old_sg_enumeratE */
/* ts A61021 : Moved most code from sg_enumerate under sg_give_next_adr() */
/* Some helper functions for sg_give_next_adr() */
static int sg_init_enumerator(burn_drive_enumerator_t *idx)
{
idx->skip_device = 0;
if ((idx->fd = open(XPT_DEVICE, O_RDWR)) == -1) {
warn("couldn't open %s", XPT_DEVICE);
return -1;
}
bzero(&(idx->ccb), sizeof(union ccb));
idx->ccb.ccb_h.path_id = CAM_XPT_PATH_ID;
idx->ccb.ccb_h.target_id = CAM_TARGET_WILDCARD;
idx->ccb.ccb_h.target_lun = CAM_LUN_WILDCARD;
idx->ccb.ccb_h.func_code = XPT_DEV_MATCH;
idx->bufsize = sizeof(struct dev_match_result) * 100;
idx->ccb.cdm.match_buf_len = idx->bufsize;
idx->ccb.cdm.matches = (struct dev_match_result *)malloc(idx->bufsize);
if (idx->ccb.cdm.matches == NULL) {
warnx("can't malloc memory for matches");
close(idx->fd);
return -1;
}
idx->ccb.cdm.num_matches = 0;
idx->i = idx->ccb.cdm.num_matches; /* to trigger buffer load */
/*
* We fetch all nodes, since we display most of them in the default
* case, and all in the verbose case.
*/
idx->ccb.cdm.num_patterns = 0;
idx->ccb.cdm.pattern_buf_len = 0;
return 1;
}
static int sg_next_enumeration_buffer(burn_drive_enumerator_t *idx)
{
/*
* We do the ioctl multiple times if necessary, in case there are
* more than 100 nodes in the EDT.
*/
if (ioctl(idx->fd, CAMIOCOMMAND, &(idx->ccb)) == -1) {
warn("error sending CAMIOCOMMAND ioctl");
return -1;
}
if ((idx->ccb.ccb_h.status != CAM_REQ_CMP)
|| ((idx->ccb.cdm.status != CAM_DEV_MATCH_LAST)
&& (idx->ccb.cdm.status != CAM_DEV_MATCH_MORE))) {
warnx("got CAM error %#x, CDM error %d\n",
idx->ccb.ccb_h.status, idx->ccb.cdm.status);
return -1;
}
return 1;
}
/** Returns the next index number and the next enumerated drive address.
@param idx An opaque handle. Make no own theories about it.
@param adr Takes the reply
@param adr_size Gives maximum size of reply including final 0
@param initialize 1 = start new,
0 = continue, use no other values for now
-1 = finish
@return 1 = reply is a valid address , 0 = no further address available
-1 = severe error (e.g. adr_size too small)
*/
int sg_give_next_adr(burn_drive_enumerator_t *idx,
char adr[], int adr_size, int initialize)
{
int ret;
if (initialize == 1) {
ret = sg_init_enumerator(idx);
if (ret<=0)
return ret;
} else if (initialize == -1) {
if(idx->fd != -1)
close(idx->fd);
idx->fd = -1;
return 0;
}
try_item:; /* This spaghetti loop keeps the number of tabs small */
/* Loop content from old sg_enumerate() */
while (idx->i >= idx->ccb.cdm.num_matches) {
ret = sg_next_enumeration_buffer(idx);
if (ret<=0)
return -1;
if (!((idx->ccb.ccb_h.status == CAM_REQ_CMP)
&& (idx->ccb.cdm.status == CAM_DEV_MATCH_MORE)) )
return 0;
idx->i = 0;
}
switch (idx->ccb.cdm.matches[idx->i].type) {
case DEV_MATCH_BUS:
break;
case DEV_MATCH_DEVICE: {
struct device_match_result* result;
result = &(idx->ccb.cdm.matches[i].result.device_result);
if (result->flags & DEV_RESULT_UNCONFIGURED)
idx->skip_device = 1;
else
idx->skip_device = 0;
break;
}
case DEV_MATCH_PERIPH: {
struct periph_match_result* result;
char buf[64];
result = &(idx->ccb.cdm.matches[i].result.periph_result);
if (idx->skip_device ||
strcmp(result->periph_name, "pass") == 0)
break;
snprintf(buf, sizeof (buf), "/dev/%s%d",
result->periph_name, result->unit_number);
if(adr_size <= strlen(buf)
return -1;
strcpy(adr, buf);
/* Found next enumerable address */
return 1;
}
default:
/* printf(stderr, "unknown match type\n"); */
break;
}
(idx->i)++;
goto try_item; /* Regular function exit is return 1 above */
}
int sg_is_enumerable_adr(char* adr)
{
burn_drive_enumerator_t idx;
int initialize = 1;
char buf[64];
while(1) {
ret = sg_give_next_adr(&idx, buf, sizeof(buf), initialize);
initialize = 0;
if (ret <= 0)
break;
if (strcmp(adr, buf) == 0) {
sg_give_next_adr(&idx, buf, sizeof(buf), -1);
return 1;
}
}
sg_give_next_adr(&idx, buf, sizeof(buf), -1);
return (0);
}
/** Try to obtain SCSI address parameters.
@return 1 is success , 0 is failure
*/
int sg_obtain_scsi_adr(char *path, int *bus_no, int *host_no, int *channel_no,
int *target_no, int *lun_no)
{
burn_drive_enumerator_t idx;
int initialize = 1;
char buf[64];
struct periph_match_result* result;
while(1) {
ret = sg_give_next_adr(&idx, buf, sizeof(buf), initialize);
initialize = 0;
if (ret <= 0)
break;
if (strcmp(adr, buf) != 0)
continue;
result = &(idx->ccb.cdm.matches[i].result.periph_result);
*bus_no = result->path_id;
*host_no = result->path_id;
*channel_no = 0;
*target_no = result->target_id
*lun_no = result->target_lun;
sg_give_next_adr(&idx, buf, sizeof(buf), -1);
return 1;
}
sg_give_next_adr(&idx, buf, sizeof(buf), -1);
return (0);
}
#endif /* ! Scsi_freebsd_old_sg_enumeratE */
int sg_close_drive(struct burn_drive * d)
{
if (d->cam != NULL) {
@ -87,13 +289,26 @@ int sg_close_drive(struct burn_drive * d)
return 0;
}
int sg_drive_is_open(struct burn_drive * d)
{
return (d->cam != NULL);
}
void ata_enumerate(void)
{
/* Do not supported */
/* ts A61021: Only a dummy function is needed in FreeBSD */
/* The difference between sg and ata should be encapsulated
in sg-linux.c */
;
}
void sg_enumerate(void)
{
#ifdef Scsi_freebsd_old_sg_enumeratE
union ccb ccb;
int bufsize, fd;
unsigned int i;
@ -188,8 +403,35 @@ void sg_enumerate(void)
&& (ccb.cdm.status == CAM_DEV_MATCH_MORE));
close(fd);
#else /* Scsi_freebsd_old_sg_enumeratE */
burn_drive_enumerator_t idx;
int initialize = 1;
char buf[64];
while(1) {
ret = sg_give_next_adr(&idx, buf, sizeof(buf), initialize);
initialize = 0;
if (ret <= 0)
break;
if (burn_drive_is_banned(buf))
continue;
enumerate_common(buf, idx.result->path_id, idx.result->path_id,
0, idx.result->target_id,
idx.result->target_lun);
}
sg_give_next_adr(&idx, buf, sizeof(buf), -1);
#endif /* ! Scsi_freebsd_old_sg_enumeratE */
}
#ifdef Scsi_freebsd_make_own_enumeratE
/* ts A61021: The old version which mixes SCSI and operating system adapter
*/
static void enumerate_common(char *fname, int bus_no, int host_no,
int channel_no, int target_no, int lun_no)
{
@ -212,6 +454,7 @@ static void enumerate_common(char *fname, int bus_no, int host_no,
out.grab = sg_grab;
out.release = sg_release;
out.drive_is_open= sg_drive_is_open;
out.issue_command = sg_issue_command;
out.getcaps = spc_getcaps;
out.released = 1;
@ -271,7 +514,41 @@ static void enumerate_common(char *fname, int bus_no, int host_no,
}
/*
#else /* Scsi_freebsd_make_own_enumeratE */
/* The new, more concise version of enumerate_common */
static void enumerate_common(char *fname, int bus_no, int host_no,
int channel_no, int target_no, int lun_no)
{
int ret;
struct burn_drive out;
/* General libburn drive setup */
burn_setup_drive(&out, fname);
/* This transport adapter uses SCSI-family commands and models
(seems the adapter would know better than its boss, if ever) */
ret = burn_scsi_setup_drive(&out, bus_no, host_no, channel_no,
target_no, lun_no, 0);
if (ret<=0)
return;
/* Operating system adapter is CAM */
/* Adapter specific handles and data */
out.cam = NULL;
/* Adapter specific functions */
out.grab = sg_grab;
out.release = sg_release;
out.drive_is_open = sg_drive_is_open;
out.issue_command = sg_issue_command;
/* Finally register drive and inquire drive information */
burn_drive_finish_enum(&out);
}
#endif /* ! Scsi_freebsd_make_own_enumeratE */
/* ts A61021: do not believe this:
we use the sg reference count to decide whether we can use the
drive or not.
if refcount is not one, drive is open somewhere else.
@ -305,6 +582,7 @@ int sg_grab(struct burn_drive *d)
return 0;
}
/*
non zero return means you still have the drive and it's not
in a state to be released? (is that even possible?)

100
libburn/sg-linux.c
View File

@ -100,6 +100,15 @@ int sg_close_drive_fd(char *fname, int driveno, int *fd, int sorry)
return 0;
}
int sg_drive_is_open(struct burn_drive * d)
{
/* a bit more detailed case distinction than needed */
if (d->fd == -1337)
return 0;
if (d->fd < 0)
return 0;
return 1;
}
/* ts A60924 */
int sg_handle_busy_device(char *fname, int os_errno)
@ -420,94 +429,37 @@ void sg_enumerate(void)
}
/* ts A60923 - A61005 : introduced new SCSI parameters */
/* ts A61021 : moved non os-specific code to spc,sbc,mmc,drive */
static void enumerate_common(char *fname, int bus_no, int host_no,
int channel_no, int target_no, int lun_no)
{
int i;
struct burn_drive *t;
int ret, i;
struct burn_drive out;
/* ts A60923 */
out.bus_no = bus_no;
out.host = host_no;
out.id = target_no;
out.channel = channel_no;
out.lun = lun_no;
/* General libburn drive setup */
burn_setup_drive(&out, fname);
out.devname = burn_strdup(fname);
/* This transport adapter uses SCSI-family commands and models
(seems the adapter would know better than its boss, if ever) */
ret = burn_scsi_setup_drive(&out, bus_no, host_no, channel_no,
target_no, lun_no, 0);
if (ret<=0)
return;
/* Operating system adapter is Linux Generic SCSI (sg) */
/* Adapter specific handles and data */
out.fd = -1337;
out.sibling_count = 0;
for(i= 0; i<LIBBURN_SG_MAX_SIBLINGS; i++)
out.sibling_fds[i] = -1337;
/* ts A61020 */
out.start_lba= -2000000000;
out.end_lba= -2000000000;
out.read_atip = mmc_read_atip;
/* Adapter specific functions */
out.grab = sg_grab;
out.release = sg_release;
out.drive_is_open= sg_drive_is_open;
out.issue_command = sg_issue_command;
out.getcaps = spc_getcaps;
out.released = 1;
out.status = BURN_DISC_UNREADY;
out.eject = sbc_eject;
out.load = sbc_load;
out.lock = spc_prevent;
out.unlock = spc_allow;
out.read_disc_info = spc_sense_write_params;
out.get_erase_progress = spc_get_erase_progress;
out.test_unit_ready = spc_test_unit_ready;
out.probe_write_modes = spc_probe_write_modes;
out.read_toc = mmc_read_toc;
out.write = mmc_write;
out.erase = mmc_erase;
out.read_sectors = mmc_read_sectors;
out.perform_opc = mmc_perform_opc;
out.set_speed = mmc_set_speed;
out.send_parameters = spc_select_error_params;
out.send_write_parameters = spc_select_write_params;
out.send_cue_sheet = mmc_send_cue_sheet;
out.sync_cache = mmc_sync_cache;
out.get_nwa = mmc_get_nwa;
out.close_disc = mmc_close_disc;
out.close_session = mmc_close_session;
out.idata = malloc(sizeof(struct burn_scsi_inquiry_data));
out.idata->valid = 0;
out.mdata = malloc(sizeof(struct scsi_mode_data));
out.mdata->valid = 0;
/* ts A61007 : obsolete Assert in drive_getcaps() */
if(out.idata == NULL || out.mdata == NULL) {
libdax_msgs_submit(libdax_messenger, -1, 0x00020108,
LIBDAX_MSGS_SEV_FATAL, LIBDAX_MSGS_PRIO_HIGH,
"Could not allocate new drive object", 0, 0);
return;
}
memset(&out.params, 0, sizeof(struct params));
t = burn_drive_register(&out);
/* ts A60821
<<< debug: for tracing calls which might use open drive fds */
mmc_function_spy("enumerate_common : -------- doing grab");
/* try to get the drive info */
if (sg_grab(t)) {
burn_print(2, "getting drive info\n");
t->getcaps(t);
t->unlock(t);
t->released = 1;
} else {
burn_print(2, "unable to grab new located drive\n");
burn_drive_unregister(t);
}
/* ts A60821
<<< debug: for tracing calls which might use open drive fds */
mmc_function_spy("enumerate_common : ----- would release ");
/* Finally register drive and inquire drive information */
burn_drive_finish_enum(&out);
}
/*

9
libburn/sg.h
View File

@ -9,7 +9,16 @@
which are now local in sg_enumerate() . So that sg_give_next_adr()
can work in BSD and sg_enumerate() can use it. */
struct burn_drive_enumeration_state {
#ifdef Scsi_freebsd_old_sg_enumeratE
int dummy;
#else
union ccb ccb;
int bufsize, fd;
unsigned int i;
int skip_device;
#endif /* ! Scsi_freebsd_old_sg_enumeratE */
};
typedef struct burn_drive_enumeration_state burn_drive_enumerator_t;

62
libburn/spc.c
View File

@ -23,6 +23,10 @@
#include "debug.h"
#include "options.h"
#include "libdax_msgs.h"
extern struct libdax_msgs *libdax_messenger;
/* spc command set */
static unsigned char SPC_INQUIRY[] = { 0x12, 0, 0, 0, 255, 0 };
@ -433,3 +437,61 @@ int spc_block_type(enum burn_block_types b)
/* ts A61007 : already prevented in burn_write_opts_set_write_type() */
/* a ssert(0); */;
}
/* ts A61021 : the spc specific part of sg.c:enumerate_common()
*/
int spc_setup_drive(struct burn_drive *d)
{
d->getcaps = spc_getcaps;
d->lock = spc_prevent;
d->unlock = spc_allow;
d->read_disc_info = spc_sense_write_params;
d->get_erase_progress = spc_get_erase_progress;
d->test_unit_ready = spc_test_unit_ready;
d->probe_write_modes = spc_probe_write_modes;
d->send_parameters = spc_select_error_params;
d->send_write_parameters = spc_select_write_params;
return 1;
}
/* ts A61021 : the general SCSI specific part of sg.c:enumerate_common()
@param flag Bitfiled for control purposes
bit0= do not setup spc/sbc/mmc
*/
int burn_scsi_setup_drive(struct burn_drive *d, int bus_no, int host_no,
int channel_no, int target_no, int lun_no, int flag)
{
int ret;
/* ts A60923 */
d->bus_no = bus_no;
d->host = host_no;
d->id = target_no;
d->channel = channel_no;
d->lun = lun_no;
d->idata = malloc(sizeof(struct burn_scsi_inquiry_data));
d->idata->valid = 0;
d->mdata = malloc(sizeof(struct scsi_mode_data));
d->mdata->valid = 0;
/* ts A61007 : obsolete Assert in drive_getcaps() */
if(d->idata == NULL || d->mdata == NULL) {
libdax_msgs_submit(libdax_messenger, -1, 0x00020108,
LIBDAX_MSGS_SEV_FATAL, LIBDAX_MSGS_PRIO_HIGH,
"Could not allocate new drive object", 0, 0);
return -1;
}
if(!(flag & 1)) {
ret = spc_setup_drive(d);
if (ret<=0)
return ret;
ret = sbc_setup_drive(d);
if (ret<=0)
return ret;
ret = mmc_setup_drive(d);
if (ret<=0)
return ret;
}
return 1;
}

12
libburn/spc.h
View File

@ -22,4 +22,16 @@ int spc_block_type(enum burn_block_types b);
int spc_get_erase_progress(struct burn_drive *d);
int spc_test_unit_ready(struct burn_drive *d);
/* ts A61021 : the spc specific part of sg.c:enumerate_common()
*/
int spc_setup_drive(struct burn_drive *d);
/* ts A61021 : the general SCSI specific part of sg.c:enumerate_common()
@param flag Bitfield for control purposes
bit0= do not setup spc/sbc/mmc
*/
int burn_scsi_setup_drive(struct burn_drive *d, int bus_no, int host_no,
int channel_no, int target_no, int lun_no, int flag);
#endif /*__SPC*/

4
libburn/transport.h
View File

@ -145,6 +145,10 @@ struct burn_drive
/* transport functions */
int (*grab) (struct burn_drive *);
int (*release) (struct burn_drive *);
/* ts A61021 */
int (*drive_is_open) (struct burn_drive *);
int (*issue_command) (struct burn_drive *, struct command *);
/* lower level functions */