udev/cdrom: introduce Context

This commit is contained in:
Yu Watanabe 2020-12-25 00:11:07 +09:00 committed by Luca Boccassi
parent 0f0b079135
commit e5aac5cdf1
1 changed files with 94 additions and 49 deletions

View File

@ -21,6 +21,7 @@
#include <time.h>
#include <unistd.h>
#include "fd-util.h"
#include "log.h"
#include "memory-util.h"
#include "random-util.h"
@ -31,6 +32,10 @@ static bool arg_lock = false;
static bool arg_unlock = false;
static const char *arg_node = NULL;
typedef struct Context {
int fd;
} Context;
/* device info */
static unsigned cd_rw_nonremovable;
static unsigned cd_rw_removable;
@ -124,6 +129,21 @@ static unsigned cd_media_track_count_data;
static unsigned cd_media_track_count_audio;
static unsigned long long int cd_media_session_last_offset;
static void context_clear(Context *c) {
if (!c)
return;
safe_close(c->fd);
}
static void context_init(Context *c) {
assert(c);
*c = (Context) {
.fd = -1,
};
}
#define ERRCODE(s) ((((s)[2] & 0x0F) << 16) | ((s)[12] << 8) | ((s)[13]))
#define SK(errcode) (((errcode) >> 16) & 0xF)
#define ASC(errcode) (((errcode) >> 8) & 0xFF)
@ -233,10 +253,12 @@ static int media_eject(int fd) {
return scsi_cmd_run_and_log(&sc, fd, NULL, 0, "start/stop unit");
}
static int cd_capability_compat(int fd) {
static int cd_capability_compat(Context *c) {
int capability;
capability = ioctl(fd, CDROM_GET_CAPABILITY, NULL);
assert(c);
capability = ioctl(c->fd, CDROM_GET_CAPABILITY, NULL);
if (capability < 0)
return log_debug_errno(errno, "CDROM_GET_CAPABILITY failed");
@ -257,24 +279,28 @@ static int cd_capability_compat(int fd) {
return 0;
}
static int cd_media_compat(int fd) {
if (ioctl(fd, CDROM_DRIVE_STATUS, CDSL_CURRENT) != CDS_DISC_OK)
static int cd_media_compat(Context *c) {
assert(c);
if (ioctl(c->fd, CDROM_DRIVE_STATUS, CDSL_CURRENT) != CDS_DISC_OK)
return log_debug_errno(errno, "CDROM_DRIVE_STATUS != CDS_DISC_OK");
cd_media = 1;
return 0;
}
static int cd_inquiry(int fd) {
static int cd_inquiry(Context *c) {
struct scsi_cmd sc;
unsigned char inq[36];
int r;
assert(c);
scsi_cmd_init(&sc);
scsi_cmd_set(&sc, 0, GPCMD_INQUIRY);
scsi_cmd_set(&sc, 4, sizeof(inq));
scsi_cmd_set(&sc, 5, 0);
r = scsi_cmd_run_and_log(&sc, fd, inq, sizeof(inq), "inquire");
r = scsi_cmd_run_and_log(&sc, c->fd, inq, sizeof(inq), "inquire");
if (r < 0)
return r;
@ -635,18 +661,19 @@ static int feature_profiles(const unsigned char *profiles, size_t size) {
return 0;
}
static int cd_profiles_old_mmc(int fd) {
static int cd_profiles_old_mmc(Context *c) {
disc_information discinfo;
struct scsi_cmd sc;
size_t len;
int r;
disc_information discinfo;
assert(c);
scsi_cmd_init(&sc);
scsi_cmd_set(&sc, 0, GPCMD_READ_DISC_INFO);
scsi_cmd_set(&sc, 8, sizeof(discinfo.disc_information_length));
scsi_cmd_set(&sc, 9, 0);
r = scsi_cmd_run_and_log(&sc, fd, (unsigned char *)&discinfo.disc_information_length, sizeof(discinfo.disc_information_length), "read disc information");
r = scsi_cmd_run_and_log(&sc, c->fd, (unsigned char *)&discinfo.disc_information_length, sizeof(discinfo.disc_information_length), "read disc information");
if (r >= 0) {
/* Not all drives have the same disc_info length, so requeue
* packet with the length the drive tells us it can supply */
@ -658,7 +685,7 @@ static int cd_profiles_old_mmc(int fd) {
scsi_cmd_set(&sc, 0, GPCMD_READ_DISC_INFO);
scsi_cmd_set(&sc, 8, len);
scsi_cmd_set(&sc, 9, 0);
r = scsi_cmd_run_and_log(&sc, fd, (unsigned char *)&discinfo, len, "read disc information");
r = scsi_cmd_run_and_log(&sc, c->fd, (unsigned char *)&discinfo, len, "read disc information");
}
if (r < 0) {
if (cd_media == 1) {
@ -688,7 +715,7 @@ static int cd_profiles_old_mmc(int fd) {
return 1;
}
static int cd_profiles(int fd) {
static int cd_profiles(Context *c) {
struct scsi_cmd sc;
unsigned char features[65530];
unsigned cur_profile = 0;
@ -697,18 +724,20 @@ static int cd_profiles(int fd) {
bool has_media = false;
int r;
assert(c);
/* First query the current profile */
scsi_cmd_init(&sc);
scsi_cmd_set(&sc, 0, GPCMD_GET_CONFIGURATION);
scsi_cmd_set(&sc, 8, 8);
scsi_cmd_set(&sc, 9, 0);
r = scsi_cmd_run(&sc, fd, features, 8);
r = scsi_cmd_run(&sc, c->fd, features, 8);
if (r != 0) {
/* handle pre-MMC2 drives which do not support GET CONFIGURATION */
if (r > 0 && SK(r) == 0x5 && IN_SET(ASC(r), 0x20, 0x24)) {
log_debug("Drive is pre-MMC2 and does not support 46h get configuration command; "
"trying to work around the problem.");
return cd_profiles_old_mmc(fd);
return cd_profiles_old_mmc(c);
}
return log_scsi_debug_errno(r, "get configuration");
@ -737,7 +766,7 @@ static int cd_profiles(int fd) {
scsi_cmd_set(&sc, 7, ( len >> 8 ) & 0xff);
scsi_cmd_set(&sc, 8, len & 0xff);
scsi_cmd_set(&sc, 9, 0);
r = scsi_cmd_run_and_log(&sc, fd, features, len, "get configuration");
r = scsi_cmd_run_and_log(&sc, c->fd, features, len, "get configuration");
if (r < 0)
return r;
@ -770,7 +799,7 @@ static int cd_profiles(int fd) {
return has_media;
}
static int cd_media_info(int fd) {
static int cd_media_info(Context *c) {
struct scsi_cmd sc;
unsigned char header[32];
static const char *const media_status[] = {
@ -781,11 +810,13 @@ static int cd_media_info(int fd) {
};
int r;
assert(c);
scsi_cmd_init(&sc);
scsi_cmd_set(&sc, 0, GPCMD_READ_DISC_INFO);
scsi_cmd_set(&sc, 8, sizeof(header));
scsi_cmd_set(&sc, 9, 0);
r = scsi_cmd_run_and_log(&sc, fd, header, sizeof(header), "read disc information");
r = scsi_cmd_run_and_log(&sc, c->fd, header, sizeof(header), "read disc information");
if (r < 0)
return r;
@ -822,7 +853,7 @@ static int cd_media_info(int fd) {
scsi_cmd_set(&sc, 7, 0xC0);
scsi_cmd_set(&sc, 9, sizeof(dvdstruct));
scsi_cmd_set(&sc, 11, 0);
r = scsi_cmd_run_and_log(&sc, fd, dvdstruct, sizeof(dvdstruct), "read DVD structure");
r = scsi_cmd_run_and_log(&sc, c->fd, dvdstruct, sizeof(dvdstruct), "read DVD structure");
if (r < 0)
return r;
@ -837,7 +868,7 @@ static int cd_media_info(int fd) {
scsi_cmd_set(&sc, 0, GPCMD_READ_FORMAT_CAPACITIES);
scsi_cmd_set(&sc, 8, sizeof(format));
scsi_cmd_set(&sc, 9, 0);
r = scsi_cmd_run_and_log(&sc, fd, format, sizeof(format), "read DVD format capacities");
r = scsi_cmd_run_and_log(&sc, c->fd, format, sizeof(format), "read DVD format capacities");
if (r < 0)
return r;
@ -876,7 +907,7 @@ static int cd_media_info(int fd) {
scsi_cmd_set(&sc, 5, 0);
scsi_cmd_set(&sc, 8, sizeof(buffer)/2048);
scsi_cmd_set(&sc, 9, 0);
r = scsi_cmd_run_and_log(&sc, fd, buffer, sizeof(buffer), "read first 32 blocks");
r = scsi_cmd_run_and_log(&sc, c->fd, buffer, sizeof(buffer), "read first 32 blocks");
if (r < 0) {
cd_media = 0;
return r;
@ -915,7 +946,7 @@ determined:
return 0;
}
static int cd_media_toc(int fd) {
static int cd_media_toc(Context *c) {
struct scsi_cmd sc;
unsigned char header[12];
unsigned char toc[65536];
@ -923,12 +954,14 @@ static int cd_media_toc(int fd) {
unsigned char *p;
int r;
assert(c);
scsi_cmd_init(&sc);
scsi_cmd_set(&sc, 0, GPCMD_READ_TOC_PMA_ATIP);
scsi_cmd_set(&sc, 6, 1);
scsi_cmd_set(&sc, 8, sizeof(header));
scsi_cmd_set(&sc, 9, 0);
r = scsi_cmd_run_and_log(&sc, fd, header, sizeof(header), "read TOC");
r = scsi_cmd_run_and_log(&sc, c->fd, header, sizeof(header), "read TOC");
if (r < 0)
return r;
@ -951,7 +984,7 @@ static int cd_media_toc(int fd) {
scsi_cmd_set(&sc, 7, (len >> 8) & 0xff);
scsi_cmd_set(&sc, 8, len & 0xff);
scsi_cmd_set(&sc, 9, 0);
r = scsi_cmd_run_and_log(&sc, fd, toc, len, "read TOC (tracks)");
r = scsi_cmd_run_and_log(&sc, c->fd, toc, len, "read TOC (tracks)");
if (r < 0)
return r;
@ -979,7 +1012,7 @@ static int cd_media_toc(int fd) {
scsi_cmd_set(&sc, 2, 1); /* Session Info */
scsi_cmd_set(&sc, 8, sizeof(header));
scsi_cmd_set(&sc, 9, 0);
r = scsi_cmd_run_and_log(&sc, fd, header, sizeof(header), "read TOC (multi session)");
r = scsi_cmd_run_and_log(&sc, c->fd, header, sizeof(header), "read TOC (multi session)");
if (r < 0)
return r;
@ -990,6 +1023,29 @@ static int cd_media_toc(int fd) {
return 0;
}
static int open_drive(Context *c) {
_cleanup_close_ int fd = -1;
assert(c);
assert(c->fd < 0);
for (int cnt = 0; cnt < 20; cnt++) {
if (cnt != 0)
(void) usleep(100 * USEC_PER_MSEC + random_u64() % (100 * USEC_PER_MSEC));
fd = open(arg_node, O_RDONLY|O_NONBLOCK|O_CLOEXEC);
if (fd >= 0 || errno != EBUSY)
break;
}
if (fd < 0)
return log_debug_errno(errno, "Unable to open '%s'", arg_node);
log_debug("probing: '%s'", arg_node);
c->fd = TAKE_FD(fd);
return 0;
}
static int help(void) {
printf("Usage: %s [options] <device>\n"
" -l --lock-media lock the media (to enable eject request events)\n"
@ -1044,79 +1100,70 @@ static int parse_argv(int argc, char *argv[]) {
}
int main(int argc, char *argv[]) {
int fd = -1;
int rc = 0;
int r;
_cleanup_(context_clear) Context c;
int r, rc = 0;
log_set_target(LOG_TARGET_AUTO);
udev_parse_config();
log_parse_environment();
log_open();
context_init(&c);
r = parse_argv(argc, argv);
if (r <= 0) {
rc = r < 0;
goto exit;
}
for (int cnt = 0; cnt < 20; cnt++) {
if (cnt != 0)
(void) usleep(100 * USEC_PER_MSEC + random_u64() % (100 * USEC_PER_MSEC));
fd = open(arg_node, O_RDONLY|O_NONBLOCK|O_CLOEXEC);
if (fd >= 0 || errno != EBUSY)
break;
}
if (fd < 0) {
log_debug("unable to open '%s'", arg_node);
if (open_drive(&c) < 0) {
rc = 1;
goto exit;
}
log_debug("probing: '%s'", arg_node);
/* same data as original cdrom_id */
if (cd_capability_compat(fd) < 0) {
if (cd_capability_compat(&c) < 0) {
rc = 1;
goto exit;
}
/* check for media - don't bail if there's no media as we still need to
* to read profiles */
cd_media_compat(fd);
cd_media_compat(&c);
/* check if drive talks MMC */
if (cd_inquiry(fd) < 0)
if (cd_inquiry(&c) < 0)
goto work;
/* read drive and possibly current profile */
r = cd_profiles(fd);
r = cd_profiles(&c);
if (r > 0) {
/* at this point we are guaranteed to have media in the drive - find out more about it */
/* get session/track info */
cd_media_toc(fd);
cd_media_toc(&c);
/* get writable media state */
cd_media_info(fd);
cd_media_info(&c);
}
work:
/* lock the media, so we enable eject button events */
if (arg_lock && cd_media) {
log_debug("PREVENT_ALLOW_MEDIUM_REMOVAL (lock)");
media_lock(fd, true);
media_lock(c.fd, true);
}
if (arg_unlock && cd_media) {
log_debug("PREVENT_ALLOW_MEDIUM_REMOVAL (unlock)");
media_lock(fd, false);
media_lock(c.fd, false);
}
if (arg_eject) {
log_debug("PREVENT_ALLOW_MEDIUM_REMOVAL (unlock)");
media_lock(fd, false);
media_lock(c.fd, false);
log_debug("START_STOP_UNIT (eject)");
media_eject(fd);
media_eject(c.fd);
}
printf("ID_CDROM=1\n");
@ -1295,8 +1342,6 @@ work:
if (cd_media_track_count_data > 0)
printf("ID_CDROM_MEDIA_TRACK_COUNT_DATA=%u\n", cd_media_track_count_data);
exit:
if (fd >= 0)
close(fd);
log_close();
return rc;
}