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freebsd-skq/usr.bin/doscmd/int13.c
tg 0689cbd99f Minor cleanup, no functional changes: 
- Add/change some comments,
- remove superfluous `if (1||x)' and re-indent,
- fix initialization of floppyinfo[] to get rid of warning.
2001-10-12 10:31:00 +00:00

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/*
* Copyright (c) 1992, 1993, 1996
* Berkeley Software Design, Inc. All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
* 3. All advertising materials mentioning features or use of this software
* must display the following acknowledgement:
* This product includes software developed by Berkeley Software
* Design, Inc.
*
* THIS SOFTWARE IS PROVIDED BY Berkeley Software Design, Inc. ``AS IS'' AND
* ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
* ARE DISCLAIMED. IN NO EVENT SHALL Berkeley Software Design, Inc. BE LIABLE
* FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
* DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
* OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
* HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
* LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
* OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
* SUCH DAMAGE.
*
* BSDI int13.c,v 2.3 1996/04/08 19:32:43 bostic Exp
*
* $FreeBSD$
*/
#include <sys/ioctl.h>
#include <sys/types.h>
#include <sys/uio.h>
#include <unistd.h>
#include "doscmd.h"
#define FDCHANGED _IOR('F', 64, int)
#define INT13_ERR_NONE 0x00
#define INT13_ERR_BAD_COMMAND 0x01
#define INT13_ERR_BAD_ADDRESS_MARK 0x02
#define INT13_ERR_WRITE_PROTECT 0x03
#define INT13_ERR_SECTOR_ID_BAD 0x04
#define INT13_ERR_RESET_FAILURE 0x05
#define INT13_ERR_CLL_ACTIVE 0x06
#define INT13_ERR_ACT_FAILED 0x07
#define INT13_ERR_DMA_OVERRUN 0x08
#define INT13_ERR_DMA_BOUNDARY 0x09
#define INT13_ERR_BAD_TRACK_FLAG 0x0B
#define INT13_ERR_MEDIA_TYP_UNKNOWN 0x0C
#define INT13_ERR_CRC 0x10
#define INT13_ERR_CORRECTED 0x11
#define INT13_ERR_CTRLR_FAILURE 0x20
#define INT13_ERR_SEEK 0x40
#define INT13_ERR_TIME_OUT 0x80
#define INT13_ERR_NOT_READY 0xAA
#define INT13_ERR_UNDEFINED 0xBB
#define INT13_ERR_SENSE_OPERATION 0xFF
typedef struct {
u_char bootIndicator;
u_char beginHead;
u_char beginSector;
u_char beginCyl;
u_char systemID;
u_char endHead;
u_char endSector;
u_char endCyl;
u_long relSector;
u_long numSectors;
} PTAB;
struct diskinfo {
int type;
int sectors;
int cylinders;
int sides;
int secsize;
int fd;
char *path;
u_long location;
u_char *sector0;
u_long offset;
char *list[4]; /* Up to 4 devices allowed */
unsigned multi:2;
int read_only:1;
int removeable:1;
int changed:1; /* Set if we change format */
};
#define hd_status (*(u_char *)0x474)
#define fd_status (*(u_char *)0x441)
static inline int
disize(struct diskinfo *di)
{
return(di->sectors * di->cylinders * di->sides);
}
static inline int
cylsize(struct diskinfo *di)
{
return(di->sectors * di->sides);
}
static u_long ftable = 0xF1000; /* Floppy table */
static u_long htable = 0xF1020; /* Hard disk table */
static struct diskinfo diskinfo[26];
static struct diskinfo floppyinfo[] = {
{0, 9, 40, 1, 512, -1, NULL, 0, NULL, 0,
{NULL, NULL, NULL, NULL}, 0, 0, 0, 0}, /* Probably not correct */
{1, 9, 40, 2, 512, -1, NULL, 0, NULL, 0,
{NULL, NULL, NULL, NULL}, 0, 0, 0, 0},
{2, 9, 80, 2, 512, -1, NULL, 0, NULL, 0,
{NULL, NULL, NULL, NULL}, 0, 0, 0, 0},
{3, 15, 80, 2, 512, -1, NULL, 0, NULL, 0,
{NULL, NULL, NULL, NULL}, 0, 0, 0, 0},
{4, 18, 80, 2, 512, -1, NULL, 0, NULL, 0,
{NULL, NULL, NULL, NULL}, 0, 0, 0, 0},
{6, 36, 80, 2, 512, -1, NULL, 0, NULL, 0,
{NULL, NULL, NULL, NULL}, 0, 0, 0, 0},
{-1, 0, 0, 0, 0, 0, NULL, 0, NULL, 0,
{NULL, NULL, NULL, NULL}, 0, 0, 0, 0}
};
static struct diskinfo *
getdisk(int drive)
{
struct diskinfo *di;
if (drive >= 2 && drive < 0x80) {
return(0);
}
if (drive >= 0x80) {
drive -= 0x80;
drive += 2;
}
if (drive > 25 || diskinfo[drive].path == 0) {
return(0);
}
di = &diskinfo[drive];
if (di->fd < 0) {
if (di->removeable) {
di->read_only = 0;
if (!(di->path = di->list[di->multi]))
di->path = di->list[di->multi = 0];
}
if ((di->fd = open(di->path, di->read_only ? O_RDONLY
: O_RDWR|O_FSYNC)) < 0 &&
(di->read_only = 1) &&
(di->fd = open(di->path, O_RDONLY)) < 0) {
return(0);
}
di->fd = squirrel_fd(di->fd);
}
return(di);
}
int
disk_fd(int drive)
{
struct diskinfo *di;
if (drive > 1)
drive += 0x80 - 2;
di = getdisk(drive);
if (!di)
return(-1);
return(di->fd);
}
void
make_readonly(int drive)
{
if (drive < 0 || drive >= 26)
return;
diskinfo[drive].read_only = 1;
}
int
init_hdisk(int drive, int cyl, int head, int tracksize, char *file, char *fake_ptab)
{
struct diskinfo *di;
u_long table;
if (drive < 0) {
for (drive = 2; drive < 26; ++drive) {
if (diskinfo[drive].path == 0)
break;
}
}
if (drive < 2) {
fprintf(stderr, "Only floppies may be assigned to A: or B:\n");
return(-1);
}
if (drive >= 26) {
fprintf(stderr, "Too many disk drives (only 24 allowed)\n");
return(-1);
}
di = &diskinfo[drive];
if (di->path) {
fprintf(stderr, "Drive %c: already assigned to %s\n", drntol(drive),
di->path);
return(-1);
}
di->fd = -1;
di->sectors = tracksize;
di->cylinders = cyl;
di->sides = head;
di->sector0 = 0;
di->offset = 0;
if (fake_ptab) {
u_char buf[512];
int fd;
PTAB *ptab;
int clusters;
if ((fd = open(fake_ptab, 0)) < 0) {
perror(fake_ptab);
return(-1);
}
di->sector0 = malloc(512);
if (!di->sector0) {
perror("malloc in init_hdisk");
quit(1);
}
read(fd, di->sector0, 512);
close(fd);
ptab = (PTAB *)(di->sector0 + 0x01BE);
for (fd = 0; fd < 4; ++fd) {
if (*(u_short *)(di->sector0 + 0x1FE) == 0xAA55 &&
ptab[fd].numSectors == head * tracksize * cyl &&
(ptab[fd].systemID == 1 || ptab[fd].systemID == 4 ||
ptab[fd].systemID == 6))
break;
}
if (fd < 4) {
if (fd)
memcpy(ptab, ptab + fd, sizeof(PTAB));
memset(ptab + 1, 0, sizeof(PTAB) * 3);
di->offset = ptab[0].relSector;
di->cylinders += di->offset / cylsize(di);
} else {
memset(ptab, 0, sizeof(PTAB) * 4);
ptab->beginHead = 0;
ptab->beginSector = 1; /* this is 1 based */
ptab->beginCyl = 1;
ptab->endHead = head - 1;
ptab->endSector = tracksize; /* this is 1 based */
ptab->endCyl = cyl & 0xff;
ptab->endSector |= (cyl & 0x300) >> 2;
ptab->relSector = head * tracksize;
ptab->numSectors = head * tracksize * cyl;
*(u_short *)(di->sector0 + 0x1FE) = 0xAA55;
fd = open(file, 0);
if (fd < 0) {
perror(file);
return(-1);
}
memset(buf, 0, 512);
read(fd, buf, 512);
close(fd);
if ((clusters = buf[0x0D]) == 0) {
if (disize(di) <= 128 * 2048)
clusters = 4;
else if (disize(di) <= 256 * 2048)
clusters = 8;
else if (disize(di) <= 8 * 1024 * 2048)
clusters = 16;
else if (disize(di) <= 16 * 1024 * 2048)
clusters = 32;
else
clusters = 64;
}
if ((disize(di) / clusters) <= 4096) {
ptab->systemID = 0x01;
} else {
ptab->systemID = 0x04;
}
di->cylinders += 1; /* Extra cylinder for partition table, etc. */
}
ptab->bootIndicator = 0x80;
}
di->type = 0xf8;
di->path = file;
di->secsize = 512;
di->path = strdup(file);
di->location = ((table & 0xf0000) << 12) | (table & 0xffff);
if (drive == 0) {
ivec[0x41] = di->location;
} else if (drive == 1) {
ivec[0x46] = di->location;
}
table = htable + (drive - 2) * 0x10;
*(u_short *)(table+0x00) = di->cylinders-1; /* Cylinders */
*(u_char *)(table+0x02) = di->sides; /* Heads */
*(u_short *)(table+0x03) = 0; /* 0 */
*(u_short *)(table+0x05) = 0xffff; /* write pre-comp */
*(u_char *)(table+0x07) = 0; /* ECC Burst length */
*(u_char *)(table+0x08) = 0; /* Control Byte */
*(u_char *)(table+0x09) = 0; /* standard timeout */
*(u_char *)(table+0x0a) = 0; /* formatting timeout */
*(u_char *)(table+0x0b) = 0; /* timeout for checking drive */
*(u_short *)(table+0x0c) = di->cylinders-1; /* landing zone */
*(u_char *)(table+0x0e) = di->sectors; /* sectors/track */
*(u_char *)(table+0x0f) = 0;
if ((drive - 1) >= ndisks)
ndisks = drive - 1;
return(drive);
}
static inline int
bps(int size)
{
switch (size) {
case 128: return(0);
case 256: return(1);
case 512: return(2);
case 1024: return(3);
default:
fprintf(stderr, "Invalid sector size: %d\n", size);
quit(1);
}
/* keep `gcc -Wall' happy */
return(0);
}
int
init_floppy(int drive, int type, char *file)
{
struct diskinfo *di = floppyinfo;
u_long table;
struct stat sb;
while (di->type >= 0 && di->type != type && disize(di)/2 != type)
++di;
if (!di->type) {
fprintf(stderr, "Invalid floppy type: %d\n", type);
return(-1);
}
if (drive < 0) {
if (diskinfo[0].path == 0) {
drive = 0;
} else if (diskinfo[1].path == 0) {
drive = 1;
} else {
fprintf(stderr, "Too many floppy drives (only 2 allowed)\n");
return(-1);
}
}
if (drive > 1) {
fprintf(stderr, "Floppies must be either drive A: or B:\n");
return(-1);
}
if (drive >= nfloppies)
nfloppies = drive + 1;
if (diskinfo[drive].path == 0) {
diskinfo[drive] = *di;
}
di = &diskinfo[drive];
if (stat(file, &sb) < 0) {
fprintf(stderr, "Drive %c: Could not stat %s\n", drntol(drive), file);
return(-1);
}
if (drive < 2 && (S_ISCHR(sb.st_mode) || S_ISBLK(sb.st_mode))) {
if (di->path && !di->removeable) {
fprintf(stderr, "Drive %c: is not removeable and hence can only have one assignment\n", drntol(drive));
return(-1);
}
di->removeable = 1;
} else if (di->removeable) {
fprintf(stderr, "Drive %c: already assigned to %s\n", drntol(drive),
di->path);
return(-1);
}
if (di->removeable) {
#if 0 /*XXXXX*/
if (di->multi == 4) {
fprintf(stderr, "Drive %c: already assigned 4 devices\n",
drntol(drive));
return(-1);
}
#endif
di->path = di->list[di->multi++] = strdup(file);
} else {
if (di->path) {
fprintf(stderr, "Drive %c: already assigned to %s\n",
drntol(drive), di->path);
return(-1);
}
di->path = strdup(file);
}
di->fd = -1;
di->location = ((table & 0xf0000) << 12) | (table & 0xffff);
di->sector0 = 0;
di->offset = 0;
ivec[0x1e] = ((ftable & 0xf0000) << 12) | (ftable & 0xffff);
table = ftable + drive * 0x0a;
*(u_char *)(table+0x00) = 0xdf; /* First Specify Byte */
*(u_char *)(table+0x01) = 0x02; /* Second Specify Byte */
*(u_char *)(table+0x02) = 0x25; /* Timer ticks to wait 'til motor OFF */
*(u_char *)(table+0x03) = bps(di->secsize); /* Number of bytes/sector */
*(u_char *)(table+0x04) = di->sectors; /* Number of sectors/track */
*(u_char *)(table+0x05) = 0x1b; /* Gap length, in bytes */
*(u_char *)(table+0x06) = 0xff; /* Data length, in bytes */
*(u_char *)(table+0x07) = 0x6c; /* Gap length for format */
*(u_char *)(table+0x09) = 0xf6; /* Fill byte for formatting */
*(u_char *)(table+0x09) = 0x0f; /* Head settle time, in milliseconds */
*(u_char *)(table+0x0a) = 0x08; /* Motor startup time, in 1/8 seconds */
return(drive);
}
int
search_floppy(int i)
{
return(i < nfloppies ? diskinfo[i].type : 0);
}
#define seterror(err) { \
if (drive & 0x80) \
hd_status = err; \
else \
fd_status = err; \
R_AH = err; \
R_FLAGS |= PSL_C; \
}
static int
trynext(struct diskinfo *di)
{
close(di->fd);
di->fd = -1;
di->changed = 1;
#if 0 /*XXXXX*/
if (di->multi++ >= 4)
return(0);
#endif
if (di->list[di->multi] && (di = getdisk(di - diskinfo))) {
di->multi = 0;
return(1);
}
return(0);
}
static int
diread(struct diskinfo *di, regcontext_t *REGS,
off_t start, char *addr, int sectors)
{
off_t res;
int drive = di - diskinfo;
di->multi = -1;
if (drive > 1) {
drive -= 2;
drive |= 0x80;
}
again:
res = lseek(di->fd, start * di->secsize, 0);
if (res < 0 && di->removeable && trynext(di))
goto again;
if (res < 0) {
seterror(INT13_ERR_SEEK);
return(-1);
}
res = read(di->fd, addr, sectors * di->secsize);
if (res < 0 && di->removeable && trynext(di))
goto again;
if (di->removeable) {
if (res < 0) {
seterror(INT13_ERR_NOT_READY);
return(-1);
}
return(res / di->secsize);
}
/*
* reads always work, if if they don't.
* Just pretend any byte not read was actually a 0
*/
if (res < 0)
memset(addr, 0, sectors * di->secsize);
else if (res < sectors * di->secsize)
memset(addr + res, 0, sectors * di->secsize - res);
return(sectors);
}
static int
diwrite(struct diskinfo *di, regcontext_t *REGS,
off_t start, char *addr, int sectors)
{
off_t res;
int drive = di - diskinfo;
di->multi = -1;
if (drive > 1) {
drive -= 2;
drive |= 0x80;
}
again:
res = lseek(di->fd, start * di->secsize, 0);
if (res < 0 && di->removeable && trynext(di))
goto again;
if (res < 0) {
seterror(INT13_ERR_SEEK);
return(-1);
}
res = write(di->fd, addr, sectors * di->secsize);
if (res < 0 && di->removeable && trynext(di))
goto again;
if (di->removeable) {
if (res < 0) {
seterror(INT13_ERR_NOT_READY);
return(-1);
}
} else if (res < 0) {
seterror(INT13_ERR_WRITE_PROTECT);
return(-1);
}
return(res / di->secsize);
}
static void
int13(regcontext_t *REGS)
{
char *addr;
int sectors;
struct diskinfo *di;
off_t start;
int did;
int cyl;
int sector;
int side;
int drive;
reset_poll();
R_FLAGS &= ~PSL_C;
drive = R_DL;
if (R_AX != 0x01) {
if (drive & 0x80)
hd_status = 0;
else
fd_status = 0;
}
switch (R_AH) {
case 0x00: /* Reset */
break;
case 0x01: /* Read disk status */
if (drive & 0x80)
R_AH = hd_status;
else
R_AH = fd_status;
if (R_AH)
R_FLAGS |= PSL_C;
break;
case 0x02: /* Read */
R_AH = 0;
addr = (char *)MAKEPTR(R_ES, R_BX);
sectors = R_AL;
side = R_DH;
R_AL = 0; /* Start out with nothing read */
if (drive & 0x80) {
cyl = R_CH | ((R_CL & 0xc0) << 2);
sector = (R_CL & 0x3f) - 1;
} else {
sector = R_CL - 1;
cyl = R_CH;
}
if ((di = getdisk(drive)) == 0) {
debug(D_DISK, "Bad drive: %02x (%d : %d : %d)\n",
drive, cyl, side, sector);
seterror(INT13_ERR_BAD_COMMAND);
break;
}
start = cyl * di->sectors * di->sides +
side * di->sectors +
sector;
if (start >= disize(di)) {
debug(D_DISK, "Read past end of disk\n");
seterror(INT13_ERR_SEEK);
break;
}
if (sectors + start >= disize(di)) {
sectors = disize(di) - start;
}
if (di->sector0) {
if (start < di->offset) {
R_AL = sectors;
if (start == 0) {
memcpy(addr, di->sector0, di->secsize);
addr += di->secsize;
--sectors;
}
memset(addr, 0, sectors * di->secsize);
break;
} else {
start -= di->offset;
}
}
debug(D_DISK, "%02x: Read %2d sectors from %qd to %04x:%04x\n",
drive, sectors, start, R_ES, R_BX);
if ((did = diread(di, REGS, start, addr, sectors)) >= 0)
R_AL = did;
#if 0
callint(0x0d);
callint(0x76);
#endif
break;
case 0x03: /* Write */
R_AH = 0;
addr = (char *)MAKEPTR(R_ES, R_BX);
sectors = R_AL;
side = R_DH;
R_AL = 0; /* Start out with nothing written */
if (drive & 0x80) {
cyl = R_CH | ((R_CL & 0xc0) << 2);
sector = (R_CL & 0x3f) - 1;
} else {
sector = R_CL - 1;
cyl = R_CH;
}
if ((di = getdisk(drive)) == 0) {
debug(D_DISK, "Bad drive: %d (%d : %d : %d)\n",
drive, cyl, side, sector);
seterror(INT13_ERR_BAD_COMMAND);
break;
}
if (di->read_only) {
debug(D_DISK, "%02x: Attempt to write readonly disk\n", drive);
seterror(INT13_ERR_WRITE_PROTECT);
break;
}
start = cyl * di->sectors * di->sides +
side * di->sectors +
sector;
if (start >= disize(di)) {
debug(D_DISK, "Write past end of disk\n");
seterror(INT13_ERR_SEEK);
break;
}
if (sectors + start >= disize(di))
sectors = disize(di) - start;
if (di->sector0) {
if (start < di->offset) {
R_AL = sectors;
break;
} else {
start -= di->offset;
}
}
debug(D_DISK, "%02x: Write %2d sectors from %qd to %04x:%04x\n",
drive, sectors, start, R_ES, R_BX);
if ((did = diwrite(di, REGS, start, addr, sectors)) >= 0)
R_AL = did;
#if 0
callint(0x0d);
callint(0x76);
#endif
break;
case 0x04: /* Verify */
R_AH = 0;
sectors = R_AL;
side = R_DH;
if (drive & 0x80) {
cyl = R_CH | ((R_CL & 0xc0) << 2);
sector = (R_CL & 0x3f) - 1;
} else {
sector = R_CL - 1;
cyl = R_CH;
}
if ((di = getdisk(drive)) == 0) {
debug(D_DISK, "Bad drive: %d (%d : %d : %d)\n",
drive, cyl, side, sector);
seterror(INT13_ERR_BAD_COMMAND);
break;
}
start = cyl * di->sectors * di->sides +
side * di->sectors +
sector;
if (start >= disize(di)) {
debug(D_DISK, "Verify past end of disk\n");
seterror(INT13_ERR_SEEK);
break;
}
if (sectors + start >= disize(di))
sectors = disize(di) - start;
if (di->sector0) {
if (start < di->offset)
break;
else
start -= di->offset;
}
debug(D_DISK, "Verify %2d sectors from %qd\n", sectors, start);
if (lseek(di->fd, start * di->secsize, 0) < 0) {
debug(D_DISK, "Seek error\n");
seterror(INT13_ERR_SEEK);
break;
}
while (sectors > 0) {
char buf[512];
if (read(di->fd, buf, di->secsize) != di->secsize) {
debug(D_DISK, "Verify error\n");
seterror(0x04);
break;
}
--sectors;
}
#if 0
callint(0x0d);
callint(0x76);
#endif
break;
case 0x05: /* Format track */
seterror(INT13_ERR_BAD_COMMAND);
break;
case 0x08: /* Status */
R_AH = 0;
if ((di = getdisk(drive)) == 0) {
debug(D_DISK, "Bad drive: %d\n", drive);
seterror(INT13_ERR_BAD_COMMAND);
break;
}
R_AX = 0;
R_BX = di->type;
if ((drive & 0x80) == 0)
PUTVEC(R_ES, R_DI, di->location);
R_CL = di->sectors | ((di->cylinders >> 2) & 0xc0);
R_CH = di->cylinders & 0xff;
R_DL = (drive & 0x80) ? ndisks : nfloppies;
R_DH = di->sides - 1;
debug(D_DISK, "%02x: Status requested: sec %d cyl %d side %d drive %d\n",
drive, R_CL, R_CH, R_DH, R_DL);
#if 0
callint(0x0d);
callint(0x76);
#endif
break;
case 0x0c: /* Move read/write head */
case 0x0d: /* Reset */
break;
case 0x10: /* check for disk ready */
R_AH = 0; /* always open for business */
break;
case 0x15:
if ((di = getdisk(drive)) == 0) {
R_AH = 0;
R_FLAGS |= PSL_C;
break;
}
if (drive & 0x80) {
start = di->sectors * di->cylinders * di->sides;
R_CX = start >> 16;
R_DX = start;
R_AH = 3;
} else {
R_AH = 1; /* Non-changeable disk */
}
break;
case 0x16: /* Media change */
R_AH = 0;
if ((di = getdisk(drive)) && di->changed) {
di->changed = 0;
R_AH = 6;
}
break;
case 0x17: /* Determine floppy disk format */
seterror(INT13_ERR_BAD_COMMAND);
break;
case 0x18: /* Determine disk format */
if ((di = getdisk(drive)) == 0) {
R_AH = 0;
R_FLAGS |= PSL_C;
break;
}
/* XXX incomplete? */
break;
default:
unknown_int2(0x13, R_AH, REGS);
break;
}
}
void
disk_bios_init(void)
{
u_long vec;
vec = insert_softint_trampoline();
ivec[0x13] = vec;
register_callback(vec, int13, "int 13");
vec = insert_null_trampoline();
ivec[0x76] = vec;
}
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