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libburn/libburn/sg-libcdio.c

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/* -*- indent-tabs-mode: t; tab-width: 8; c-basic-offset: 8; -*- */
/*
This is the main operating system dependent SCSI part of libburn. It implements
the transport level aspects of SCSI control and command i/o.
Present implementation: GNU libcdio , for X/Open compliant operating systems
PORTING:
Porting libburn typically will consist of adding a new operating system case
to the following switcher files:
os.h Operating system specific libburn definitions and declarations.
sg.c Operating system dependent transport level modules.
and of deriving the following system specific files from existing examples:
os-*.h Included by os.h. You will need some general system knowledge
about signals and knowledge about the storage object needs of your
transport level module sg-*.c.
sg-*.c This source module. You will need special system knowledge about
how to detect all potentially available drives, how to open them,
eventually how to exclusively reserve them, how to perform
SCSI transactions, how to inquire the (pseudo-)SCSI driver.
You will not need to care about CD burning, MMC or other high-level
SCSI aspects.
Said sg-*.c operations are defined by a public function interface, which has
to be implemented in a way that provides libburn with the desired services:
sg_id_string() returns an id string of the SCSI transport adapter.
It may be called before initialization but then may
return only a preliminary id.
sg_initialize() performs global initialization of the SCSI transport
adapter and eventually needed operating system
facilities. Checks for compatibility of supporting
software components.
sg_shutdown() performs global finalizations and releases golbally
aquired resources.
sg_give_next_adr() iterates over the set of potentially useful drive
address strings.
scsi_enumerate_drives() brings all available, not-whitelist-banned, and
accessible drives into libburn's list of drives.
sg_dispose_drive() finalizes adapter specifics of struct burn_drive
on destruction. Releases resources which were aquired
underneath scsi_enumerate_drives().
sg_drive_is_open() tells wether libburn has the given drive in use.
sg_grab() opens the drive for SCSI commands and ensures
undisturbed access.
sg_release() closes a drive opened by sg_grab()
sg_issue_command() sends a SCSI command to the drive, receives reply,
and evaluates wether the command succeeded or shall
be retried or finally failed.
sg_obtain_scsi_adr() tries to obtain SCSI address parameters.
burn_os_stdio_capacity() estimates the emulated media space of stdio-drives.
burn_os_open_track_src() opens a disk file in a way that allows best
throughput with file reading and/or SCSI write command
transmission.
burn_os_alloc_buffer() allocates a memory area that is suitable for file
descriptors issued by burn_os_open_track_src().
The buffer size may be rounded up for alignment
reasons.
burn_os_free_buffer() delete a buffer obtained by burn_os_alloc_buffer().
Porting hints are marked by the text "PORTING:".
Send feedback to libburn-hackers@pykix.org .
*/
/** PORTING : ------- OS dependent headers and definitions ------ */
#include <unistd.h>
#include <stdio.h>
#include <sys/types.h>
#include <errno.h>
#include <fcntl.h>
#include <sys/stat.h>
#include <string.h>
#include <stdlib.h>
#ifdef Libburn_os_has_statvfS
#include <sys/statvfs.h>
#endif /* Libburn_os_has_stavtfS */
#ifdef __linux
/* for ioctl(BLKGETSIZE) */
#include <sys/ioctl.h>
#include <linux/fs.h>
#endif
#include <cdio/cdio.h>
#include <cdio/logging.h>
#include <cdio/mmc.h>
/* The waiting time before eventually retrying a failed SCSI command.
Before each retry wait Libburn_sg_linux_retry_incR longer than with
the previous one.
*/
#define Libburn_sg_libcdio_retry_usleeP 100000
#define Libburn_sg_libcdio_retry_incR 100000
/** PORTING : ------ libburn portable headers and definitions ----- */
#include "transport.h"
#include "drive.h"
#include "sg.h"
#include "spc.h"
/* collides with symbols of <cdio/mmc.h>
#include "mmc.h"
*/
#include "sbc.h"
#include "debug.h"
#include "toc.h"
#include "util.h"
#include "libdax_msgs.h"
extern struct libdax_msgs *libdax_messenger;
/* is in portable part of libburn */
int burn_drive_is_banned(char *device_address);
int burn_drive_resolve_link(char *path, char adr[],
int *recursion_count, int flag); /* drive.c */
/* Whether to log SCSI commands:
bit0= log in /tmp/libburn_sg_command_log
bit1= log to stderr
bit2= flush every line
*/
extern int burn_sg_log_scsi;
/* ------------------------------------------------------------------------ */
/* PORTING: Private definitions. Port only if needed by public functions. */
/* (Public functions are listed below) */
/* ------------------------------------------------------------------------ */
/* Storage object is in libburn/init.c
whether to strive for exclusive access to the drive
*/
extern int burn_sg_open_o_excl;
/* ------------------------------------------------------------------------ */
/* PORTING: Private functions. Port only if needed by public functions */
/* (Public functions are listed below) */
/* ------------------------------------------------------------------------ */
static int sg_close_drive(struct burn_drive * d)
{
CdIo_t *p_cdio;
if (d->p_cdio != NULL) {
p_cdio = (CdIo_t *) d->p_cdio;
cdio_destroy(p_cdio);
d->p_cdio = NULL;
}
return 0;
}
static int sg_give_next_adr_raw(burn_drive_enumerator_t *idx,
char adr[], int adr_size, int initialize)
{
char **pos;
int count = 0;
if (initialize == 1) {
idx->pos = idx->ppsz_cd_drives =
cdio_get_devices(DRIVER_DEVICE);
if (idx->ppsz_cd_drives == NULL)
return 0;
for (pos = idx->ppsz_cd_drives ; pos != NULL; pos++) {
if (*pos == NULL)
break;
count++;
}
} else if (initialize == -1) {
if (*(idx->ppsz_cd_drives) != NULL)
cdio_free_device_list(idx->ppsz_cd_drives);
idx->ppsz_cd_drives = NULL;
}
if (idx->pos == NULL)
return 0;
if (*(idx->pos) == NULL)
return 0;
if (strlen(*(idx->pos)) >= adr_size)
return -1;
strcpy(adr, *(idx->pos));
(idx->pos)++;
return 1;
}
/* ----------------------------------------------------------------------- */
/* PORTING: Private functions which contain publicly needed functionality. */
/* Their portable part must be performed. So it is probably best */
/* to replace the non-portable part and to call these functions */
/* in your port, too. */
/* ----------------------------------------------------------------------- */
/** Wraps a detected drive into libburn structures and hands it over to
libburn drive list.
*/
static void enumerate_common(char *fname, char *cdio_name,
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;
/* PORTING: ------------------- non portable part --------------- */
/* Transport adapter is libcdio */
/* Adapter specific handles and data */
out.p_cdio = NULL;
strcpy(out.libcdio_name, fname);
if (strlen(cdio_name) < sizeof(out.libcdio_name))
strcpy(out.libcdio_name, cdio_name);
/* PORTING: ---------------- end of non portable part ------------ */
/* Adapter specific functions with standardized names */
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);
}
/* ------------------------------------------------------------------------ */
/* PORTING: Public functions. These MUST be ported. */
/* ------------------------------------------------------------------------ */
/** Returns the id string of the SCSI transport adapter and eventually
needed operating system facilities.
This call is usable even if sg_initialize() was not called yet. In that
case a preliminary constant message might be issued if detailed info is
not available yet.
@param msg returns id string
@param flag unused yet, submit 0
@return 1 = success, <=0 = failure
*/
int sg_id_string(char msg[1024], int flag)
{
char *version_text;
sprintf(msg, "sg-libcdio h%d with libcdio ", LIBCDIO_VERSION_NUM);
#if LIBCDIO_VERSION_NUM < 83
LIBBURN_MISCONFIGURATION = 0;
INTENTIONAL_ABORT_OF_COMPILATION__HEADERFILE_cdio_version_dot_h_TOO_OLD__NEED_libcdio_VERSION_NUM_83 = 0;
LIBBURN_MISCONFIGURATION_ = 0;
#endif /* LIBCDIO_VERSION_NUM < 83 */
version_text = (char *) cdio_version_string;
strncat(msg, version_text, 800);
return 1;
}
/** Performs global initialization of the SCSI transport adapter and eventually
needed operating system facilities. Checks for compatibility of supporting
software components.
@param msg returns ids and/or error messages of eventual helpers
@param flag unused yet, submit 0
@return 1 = success, <=0 = failure
*/
int sg_initialize(char msg[1024], int flag)
{
int cdio_ver;
char *msg_pt;
cdio_loglevel_default = CDIO_LOG_ASSERT;
msg[0] = 0;
sg_id_string(msg, 0);
cdio_ver = libcdio_version_num;
libdax_msgs_submit(libdax_messenger, -1, 0x00000002,
LIBDAX_MSGS_SEV_DEBUG, LIBDAX_MSGS_PRIO_HIGH,
msg , 0, 0);
if (cdio_ver < LIBCDIO_VERSION_NUM) {
strcat(msg, " ---> ");
msg_pt = msg + strlen(msg);
sprintf(msg_pt,
"libcdio TOO OLD: numeric version %d , need at least %d",
cdio_ver, LIBCDIO_VERSION_NUM);
libdax_msgs_submit(libdax_messenger, -1,
0x00000002,
LIBDAX_MSGS_SEV_DEBUG, LIBDAX_MSGS_PRIO_HIGH,
msg_pt, 0, 0);
return 0;
}
return 1;
}
/** Performs global finalization of the SCSI transport adapter and eventually
needed operating system facilities. Releases globally aquired resources.
@param flag unused yet, submit 0
@return 1 = success, <=0 = failure
*/
int sg_shutdown(int flag)
{
return 1;
}
/** Finalizes BURN_OS_TRANSPORT_DRIVE_ELEMENTS, the components of
struct burn_drive which are defined in os-*.h.
The eventual initialization of those components was made underneath
scsi_enumerate_drives().
This will be called when a burn_drive gets disposed.
@param d the drive to be finalized
@param flag unused yet, submit 0
@return 1 = success, <=0 = failure
*/
int sg_dispose_drive(struct burn_drive *d, int flag)
{
return 1;
}
/** Returns the next index number and the next enumerated drive address.
The enumeration has to cover all available and accessible drives. It is
allowed to return addresses of drives which are not available but under
some (even exotic) circumstances could be available. It is on the other
hand allowed, only to hand out addresses which can really be used right
in the moment of this call. (This implementation chooses the latter.)
@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, recursion_count = 0;
char path[4096];
ret = sg_give_next_adr_raw(idx, adr, adr_size, initialize);
if (ret <= 0)
return ret;
if (strlen(adr) >= sizeof(path))
return ret;
strcpy(path, adr);
ret = burn_drive_resolve_link(path, adr, &recursion_count, 2);
return (ret >= 0);
}
/** Brings all available, not-whitelist-banned, and accessible drives into
libburn's list of drives.
*/
int scsi_enumerate_drives(void)
{
burn_drive_enumerator_t idx;
int initialize = 1, ret, i_bus_no = -1, recursion_count = 0;
int i_host_no = -1, i_channel_no = -1, i_target_no = -1, i_lun_no = -1;
char buf[4096], target[4096];
while(1) {
ret = sg_give_next_adr_raw(&idx, buf, sizeof(buf), initialize);
initialize = 0;
if (ret <= 0)
break;
ret = burn_drive_resolve_link(buf, target, &recursion_count,2);
if (ret <= 0)
strcpy(target, buf);
if (burn_drive_is_banned(target))
continue;
sg_obtain_scsi_adr(buf, &i_bus_no, &i_host_no,
&i_channel_no, &i_target_no, &i_lun_no);
enumerate_common(target, buf,
i_bus_no, i_host_no, i_channel_no,
i_target_no, i_lun_no);
}
sg_give_next_adr(&idx, buf, sizeof(buf), -1);
return 1;
}
/** Tells whether libburn has the given drive in use or exclusively reserved.
If it is "open" then libburn will eventually call sg_release() on it when
it is time to give up usage resp. reservation.
*/
/** Published as burn_drive.drive_is_open() */
int sg_drive_is_open(struct burn_drive * d)
{
return (d->p_cdio != NULL);
}
/** Opens the drive for SCSI commands and - if burn activities are prone
to external interference on your system - obtains an exclusive access lock
on the drive. (Note: this is not physical tray locking.)
A drive that has been opened with sg_grab() will eventually be handed
over to sg_release() for closing and unreserving.
*/
int sg_grab(struct burn_drive *d)
{
CdIo_t *p_cdio;
char *am_eff, msg[4096], *am_wanted;
int os_errno, second_try = 0;
if (d->p_cdio != NULL) {
d->released = 0;
return 1;
}
if (d->libcdio_name[0] == 0) /* just to be sure it is initialized */
strcpy(d->libcdio_name, d->devname);
am_wanted = burn_sg_open_o_excl ? "MMC_RDWR_EXCL" : "MMC_RDWR";
try_to_open:;
p_cdio = cdio_open_am(d->libcdio_name, DRIVER_DEVICE, am_wanted);
if (p_cdio == NULL) {
os_errno = errno;
sprintf(msg, "Could not grab drive '%s'", d->devname);
libdax_msgs_submit(libdax_messenger, d->global_index,
0x00020003,
LIBDAX_MSGS_SEV_SORRY, LIBDAX_MSGS_PRIO_HIGH,
msg, os_errno, 0);
return 0;
}
am_eff = (char *) cdio_get_arg(p_cdio, "access-mode");
if (strncmp(am_eff, "MMC_RDWR", 8) != 0) {
cdio_destroy(p_cdio);
if (!second_try) {
am_wanted = burn_sg_open_o_excl ?
"MMC_RDWR" : "MMC_RDWR_EXCL";
second_try = 1;
goto try_to_open;
}
libdax_msgs_submit(libdax_messenger, d->global_index,
0x00020003,
LIBDAX_MSGS_SEV_SORRY, LIBDAX_MSGS_PRIO_HIGH,
"libcdio provides no MMC_RDWR access mode", 0, 0);
return 0;
}
d->p_cdio = p_cdio;
d->released = 0;
return 1;
}
/** PORTING: Is mainly about the call to sg_close_drive() and whether it
implements the demanded functionality.
*/
/** Gives up the drive for SCSI commands and releases eventual access locks.
(Note: this is not physical tray locking.)
*/
int sg_release(struct burn_drive *d)
{
if (d->p_cdio == NULL) {
burn_print(1, "release an ungrabbed drive. die\n");
return 0;
}
sg_close_drive(d);
return 0;
}
/** Sends a SCSI command to the drive, receives reply and evaluates wether
the command succeeded or shall be retried or finally failed.
Returned SCSI errors shall not lead to a return value indicating failure.
The callers get notified by c->error. An SCSI failure which leads not to
a retry shall be notified via scsi_notify_error().
The Libburn_log_sg_commandS facility might be of help when problems with
a drive have to be examined. It shall stay disabled for normal use.
@return: 1 success , <=0 failure
*/
int sg_issue_command(struct burn_drive *d, struct command *c)
{
int sense_valid = 0, i, usleep_time, timeout_ms;
time_t start_time;
driver_return_code_t i_status;
unsigned int dxfer_len;
static FILE *fp = NULL;
mmc_cdb_t cdb = {{0, }};
cdio_mmc_direction_t e_direction;
CdIo_t *p_cdio;
unsigned char *sense_pt = NULL;
c->error = 0;
if (d->p_cdio == NULL) {
return 0;
}
p_cdio = (CdIo_t *) d->p_cdio;
if (burn_sg_log_scsi & 1) {
if (fp == NULL) {
fp= fopen("/tmp/libburn_sg_command_log", "a");
fprintf(fp,
"\n-----------------------------------------\n");
}
}
if (burn_sg_log_scsi & 3)
scsi_log_cmd(c,fp,0);
memcpy(cdb.field, c->opcode, c->oplen);
if (c->dir == TO_DRIVE) {
dxfer_len = c->page->bytes;
e_direction = SCSI_MMC_DATA_WRITE;
} else if (c->dir == FROM_DRIVE) {
if (c->dxfer_len >= 0)
dxfer_len = c->dxfer_len;
else
dxfer_len = BUFFER_SIZE;
e_direction = SCSI_MMC_DATA_READ;
/* touch page so we can use valgrind */
memset(c->page->data, 0, BUFFER_SIZE);
} else {
dxfer_len = 0;
e_direction = SCSI_MMC_DATA_NONE;
}
/* retry-loop */
start_time = time(NULL);
timeout_ms = 200000;
for(i = 0; ; i++) {
i_status = mmc_run_cmd(p_cdio, timeout_ms, &cdb, e_direction,
dxfer_len, c->page->data);
sense_valid = mmc_last_cmd_sense(p_cdio, &sense_pt);
if (sense_valid >= 18)
memcpy(c->sense, sense_pt,
sense_valid >= sizeof(c->sense) ?
sizeof(c->sense) : sense_valid );
if (sense_pt != NULL)
free(sense_pt);
/* Regrettably mmc_run_cmd() does not clearly distinguish between transport
failure and SCSI error reply.
This reaction here would be for transport failure:
if (i_status != 0 && i_status != DRIVER_OP_ERROR) {
libdax_msgs_submit(libdax_messenger,
d->global_index, 0x0002010c,
LIBDAX_MSGS_SEV_FATAL, LIBDAX_MSGS_PRIO_HIGH,
"Failed to transfer command to drive",
errno, 0);
sg_close_drive(d);
d->released = 1;
d->busy = BURN_DRIVE_IDLE;
c->error = 1;
return -1;
}
*/
if (!sense_valid) {
memset(c->sense, 0, sizeof(c->sense));
if (i_status != 0) { /* set dummy sense */
/*LOGICAL UNIT NOT READY,CAUSE NOT REPORTABLE*/
c->sense[2] = 0x02;
c->sense[12] = 0x04;
}
} else
c->sense[2] &= 15;
if (i_status != 0 ||
(c->sense[2] || c->sense[12] || c->sense[13])) {
if (!c->retry) {
c->error = 1;
goto ex;
}
switch (scsi_error(d, c->sense, 18)) {
case RETRY:
break;
case FAIL:
c->error = 1;
goto ex;
}
/*
Calming down retries and breaking up endless cycle
*/
usleep_time = Libburn_sg_libcdio_retry_usleeP +
i * Libburn_sg_libcdio_retry_incR;
if (time(NULL) + usleep_time / 1000000 - start_time >
timeout_ms / 1000 + 1) {
c->error = 1;
goto ex;
}
usleep(usleep_time);
} else
break; /* retry-loop */
} /* end of retry-loop */
ex:;
if (c->error)
scsi_notify_error(d, c, c->sense, 18, 0);
if (burn_sg_log_scsi & 3)
/* >>> Need own duration time measurement. Then remove bit1 */
scsi_log_err(c, fp, c->sense, 0, (c->error != 0) | 2);
return 1;
}
/** Tries 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)
{
CdIo_t *p_cdio;
char *tuple;
*bus_no = *host_no = *channel_no = *target_no = *lun_no = -1;
p_cdio = cdio_open(path, DRIVER_DEVICE);
if (p_cdio == NULL)
return 0;
/* Try whether a Linux address tuple is available */
tuple = (char *) cdio_get_arg(p_cdio, "scsi-tuple-linux");
if (tuple != NULL) if (tuple[0]) {
sscanf(tuple, "%d,%d,%d,%d,%d",
bus_no, host_no, channel_no, target_no, lun_no);
}
cdio_destroy(p_cdio);
return (*bus_no >= 0);
}
/** Tells wether a text is a persistent address as listed by the enumeration
functions.
*/
int sg_is_enumerable_adr(char* adr)
{
burn_drive_enumerator_t idx;
int initialize = 1, ret;
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);
}
/** Estimate the potential payload capacity of a file address.
@param path The address of the file to be examined. If it does not
exist yet, then the directory will be inquired.
@param bytes The pointed value gets modified, but only if an estimation is
possible.
@return -2 = cannot perform necessary operations on file object
-1 = neither path nor dirname of path exist
0 = could not estimate size capacity of file object
1 = estimation has been made, bytes was set
*/
int burn_os_stdio_capacity(char *path, off_t *bytes)
{
struct stat stbuf;
#ifdef Libburn_os_has_statvfS
struct statvfs vfsbuf;
#endif
char testpath[4096], *cpt;
long blocks;
off_t add_size = 0;
testpath[0] = 0;
blocks = *bytes / 512;
if (stat(path, &stbuf) == -1) {
strcpy(testpath, path);
cpt = strrchr(testpath, '/');
if(cpt == NULL)
strcpy(testpath, ".");
else if(cpt == testpath)
testpath[1] = 0;
else
*cpt = 0;
if (stat(testpath, &stbuf) == -1)
return -1;
#ifdef __linux
/* Linux specific determination of block device size */
} else if(S_ISBLK(stbuf.st_mode)) {
int open_mode = O_RDONLY, fd, ret;
fd = open(path, open_mode);
if (fd == -1)
return -2;
ret = ioctl(fd, BLKGETSIZE, &blocks);
close(fd);
if (ret == -1)
return -2;
*bytes = ((off_t) blocks) * (off_t) 512;
#endif /* __linux */
} else if(S_ISREG(stbuf.st_mode)) {
add_size = stbuf.st_blocks * (off_t) 512;
strcpy(testpath, path);
} else
return 0;
if (testpath[0]) {
#ifdef Libburn_os_has_statvfS
if (statvfs(testpath, &vfsbuf) == -1)
return -2;
*bytes = add_size + ((off_t) vfsbuf.f_frsize) *
(off_t) vfsbuf.f_bavail;
#else /* Libburn_os_has_statvfS */
return 0;
#endif /* ! Libburn_os_has_stavtfS */
}
return 1;
}
/* ts A91122 : an interface to open(O_DIRECT) or similar OS tricks. */
#ifdef Libburn_read_o_direcT
/* No special O_DIRECT-like precautions are implemented here */
#endif /* Libburn_read_o_direcT */
int burn_os_open_track_src(char *path, int open_flags, int flag)
{
int fd;
fd = open(path, open_flags);
return fd;
}
void *burn_os_alloc_buffer(size_t amount, int flag)
{
void *buf = NULL;
buf = calloc(1, amount);
return buf;
}
int burn_os_free_buffer(void *buffer, size_t amount, int flag)
{
if (buffer == NULL)
return 0;
free(buffer);
return 1;
}
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