 602233213e
			
		
	
	
		602233213e
		
	
	
	
	
		
			
			- Add load_mods command to boot2 (load_mods /dir/mod*). - Rename resulting binary to boot_monitor. - Change default banner when used in MINIX.
		
			
				
	
	
		
			799 lines
		
	
	
		
			18 KiB
		
	
	
	
		
			C
		
	
	
	
	
	
			
		
		
	
	
			799 lines
		
	
	
		
			18 KiB
		
	
	
	
		
			C
		
	
	
	
	
	
| /*	$NetBSD: dosfs.c,v 1.18 2011/12/25 06:09:08 tsutsui Exp $	*/
 | |
| 
 | |
| /*
 | |
|  * Copyright (c) 1996, 1998 Robert Nordier
 | |
|  * 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.
 | |
|  *
 | |
|  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR(S) ``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 THE AUTHOR(S) 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.
 | |
|  */
 | |
| 
 | |
| /*
 | |
|  * Readonly filesystem for Microsoft FAT12/FAT16/FAT32 filesystems,
 | |
|  * also supports VFAT.
 | |
|  */
 | |
| 
 | |
| /*
 | |
|  * XXX DOES NOT SUPPORT:
 | |
|  *
 | |
|  *	LIBSA_FS_SINGLECOMPONENT
 | |
|  */
 | |
| 
 | |
| #include <sys/param.h>
 | |
| 
 | |
| #include <fs/msdosfs/bpb.h>
 | |
| #include <fs/msdosfs/direntry.h>
 | |
| 
 | |
| #ifdef _STANDALONE
 | |
| #include <lib/libkern/libkern.h>
 | |
| #else
 | |
| #include <string.h>
 | |
| #include <stddef.h>
 | |
| #endif
 | |
| 
 | |
| #include "stand.h"
 | |
| #include "dosfs.h"
 | |
| 
 | |
| #define SECSIZ  512		/* sector size */
 | |
| #define SSHIFT    9		/* SECSIZ shift */
 | |
| #define DEPSEC   16		/* directory entries per sector */
 | |
| #define DSHIFT    4		/* DEPSEC shift */
 | |
| #define LOCLUS    2		/* lowest cluster number */
 | |
| 
 | |
| typedef union {
 | |
| 	struct direntry de;	/* standard directory entry */
 | |
| 	struct winentry xde;	/* extended directory entry */
 | |
| } DOS_DIR;
 | |
| 
 | |
| typedef struct {
 | |
| 	struct open_file *fd;	/* file descriptor */
 | |
| 	u_char *buf;		/* buffer */
 | |
| 	u_int   bufsec;		/* buffered sector */
 | |
| 	u_int   links;		/* active links to structure */
 | |
| 	u_int   spc;		/* sectors per cluster */
 | |
| 	u_int   bsize;		/* cluster size in bytes */
 | |
| 	u_int   bshift;		/* cluster conversion shift */
 | |
| 	u_int   dirents;	/* root directory entries */
 | |
| 	u_int   spf;		/* sectors per fat */
 | |
| 	u_int   rdcl;		/* root directory start cluster */
 | |
| 	u_int   lsnfat;		/* start of fat */
 | |
| 	u_int   lsndir;		/* start of root dir */
 | |
| 	u_int   lsndta;		/* start of data area */
 | |
| 	u_int   fatsz;		/* FAT entry size */
 | |
| 	u_int   xclus;		/* maximum cluster number */
 | |
| } DOS_FS;
 | |
| 
 | |
| typedef struct {
 | |
| 	DOS_FS *fs;		/* associated filesystem */
 | |
| 	struct direntry de;	/* directory entry */
 | |
| 	u_int   offset;		/* current offset */
 | |
| 	u_int   c;		/* last cluster read */
 | |
| } DOS_FILE;
 | |
| 
 | |
| /* Initial portion of DOS boot sector */
 | |
| typedef struct {
 | |
| 	u_char  jmp[3];		/* usually 80x86 'jmp' opcode */
 | |
| 	u_char  oem[8];		/* OEM name and version */
 | |
| 	struct byte_bpb710 bpb;	/* BPB */
 | |
| } DOS_BS;
 | |
| 
 | |
| /* Supply missing "." and ".." root directory entries */
 | |
| static const char *const dotstr[2] = {".", ".."};
 | |
| static const struct direntry dot[2] = {
 | |
| 	{".       ", "   ", ATTR_DIRECTORY,
 | |
| 		0, 0, {0, 0}, {0, 0}, {0, 0}, {0, 0},
 | |
| 		{0, 0}, {0x21, 0}, {0, 0}, {0, 0, 0, 0}},
 | |
| 
 | |
| 	{"..      ", "   ", ATTR_DIRECTORY,
 | |
| 		0, 0, {0, 0}, {0, 0}, {0, 0}, {0, 0},
 | |
| 		{0, 0}, {0x21, 0}, {0, 0}, {0, 0, 0, 0}}
 | |
| };
 | |
| 
 | |
| /* The usual conversion macros to avoid multiplication and division */
 | |
| #define bytsec(n)      ((n) >> SSHIFT)
 | |
| #define secbyt(s)      ((s) << SSHIFT)
 | |
| #define entsec(e)      ((e) >> DSHIFT)
 | |
| #define bytblk(fs, n)  ((n) >> (fs)->bshift)
 | |
| #define blkbyt(fs, b)  ((b) << (fs)->bshift)
 | |
| #define secblk(fs, s)  ((s) >> ((fs)->bshift - SSHIFT))
 | |
| #define blksec(fs, b)  ((b) << ((fs)->bshift - SSHIFT))
 | |
| 
 | |
| /* Convert cluster number to offset within filesystem */
 | |
| #define blkoff(fs, b) (secbyt((fs)->lsndta) + blkbyt(fs, (b) - LOCLUS))
 | |
| 
 | |
| /* Convert cluster number to logical sector number */
 | |
| #define blklsn(fs, b)  ((fs)->lsndta + blksec(fs, (b) - LOCLUS))
 | |
| 
 | |
| /* Convert cluster number to offset within FAT */
 | |
| #define fatoff(sz, c)  ((sz) == 12 ? (c) + ((c) >> 1) :  \
 | |
|                         (sz) == 16 ? (c) << 1 :          \
 | |
|                         (c) << 2)
 | |
| 
 | |
| /* Does cluster number reference a valid data cluster? */
 | |
| #define okclus(fs, c)  ((c) >= LOCLUS && (c) <= (fs)->xclus)
 | |
| 
 | |
| /* Get start cluster from directory entry */
 | |
| #define stclus(sz, de)  ((sz) != 32 ? (u_int)getushort((de)->deStartCluster) : \
 | |
|                          ((u_int)getushort((de)->deHighClust) << 16) |  \
 | |
|                          (u_int)getushort((de)->deStartCluster))
 | |
| 
 | |
| static int dosunmount(DOS_FS *);
 | |
| static int parsebs(DOS_FS *, DOS_BS *);
 | |
| static int namede(DOS_FS *, const char *, const struct direntry **);
 | |
| static int lookup(DOS_FS *, u_int, const char *, const struct direntry **);
 | |
| static void cp_xdnm(u_char *, struct winentry *);
 | |
| static void cp_sfn(u_char *, struct direntry *);
 | |
| static off_t fsize(DOS_FS *, struct direntry *);
 | |
| static int fatcnt(DOS_FS *, u_int);
 | |
| static int fatget(DOS_FS *, u_int *);
 | |
| static int fatend(u_int, u_int);
 | |
| static int ioread(DOS_FS *, u_int, void *, u_int);
 | |
| static int iobuf(DOS_FS *, u_int);
 | |
| static int ioget(struct open_file *, u_int, void *, u_int);
 | |
| 
 | |
| #define strcasecmp(s1, s2) dos_strcasecmp(s1, s2)
 | |
| static int
 | |
| strcasecmp(const char *s1, const char *s2)
 | |
| {
 | |
| 	char c1, c2;
 | |
| 	#define TO_UPPER(c) ((c) >= 'a' && (c) <= 'z' ? (c) - ('a' - 'A') : (c))
 | |
| 	for (;;) {
 | |
| 		c1 = *s1++;
 | |
| 		c2 = *s2++;
 | |
| 		if (TO_UPPER(c1) != TO_UPPER(c2))
 | |
| 			return 1;
 | |
| 		if (c1 == 0)
 | |
| 			return 0;
 | |
| 	}
 | |
| 	#undef TO_UPPER
 | |
| }
 | |
| 
 | |
| /*
 | |
|  * Mount DOS filesystem
 | |
|  */
 | |
| static int
 | |
| dos_mount(DOS_FS *fs, struct open_file *fd)
 | |
| {
 | |
| 	int     err;
 | |
| 
 | |
| 	(void)memset(fs, 0, sizeof(DOS_FS));
 | |
| 	fs->fd = fd;
 | |
| 	if ((err = !(fs->buf = alloc(SECSIZ)) ? errno : 0) ||
 | |
| 	    (err = ioget(fs->fd, 0, fs->buf, 1)) ||
 | |
| 	    (err = parsebs(fs, (DOS_BS *)fs->buf))) {
 | |
| 		(void) dosunmount(fs);
 | |
| 		return err;
 | |
| 	}
 | |
| 	return 0;
 | |
| }
 | |
| 
 | |
| #ifndef LIBSA_NO_FS_CLOSE
 | |
| /*
 | |
|  * Unmount mounted filesystem
 | |
|  */
 | |
| static int
 | |
| dos_unmount(DOS_FS *fs)
 | |
| {
 | |
| 	int     err;
 | |
| 
 | |
| 	if (fs->links)
 | |
| 		return EBUSY;
 | |
| 	if ((err = dosunmount(fs)))
 | |
| 		return err;
 | |
| 	return 0;
 | |
| }
 | |
| #endif
 | |
| 
 | |
| /*
 | |
|  * Common code shared by dos_mount() and dos_unmount()
 | |
|  */
 | |
| static int
 | |
| dosunmount(DOS_FS *fs)
 | |
| {
 | |
| 	if (fs->buf)
 | |
| 		dealloc(fs->buf, SECSIZ);
 | |
| 	dealloc(fs, sizeof(DOS_FS));
 | |
| 	return 0;
 | |
| }
 | |
| 
 | |
| /*
 | |
|  * Open DOS file
 | |
|  */
 | |
| __compactcall int
 | |
| dosfs_open(const char *path, struct open_file *fd)
 | |
| {
 | |
| 	const struct direntry *de;
 | |
| 	DOS_FILE *f;
 | |
| 	DOS_FS *fs;
 | |
| 	u_int   size, clus;
 | |
| 	int     err = 0;
 | |
| 
 | |
| 	/* Allocate mount structure, associate with open */
 | |
| 	fs = alloc(sizeof(DOS_FS));
 | |
| 
 | |
| 	if ((err = dos_mount(fs, fd)))
 | |
| 		goto out;
 | |
| 
 | |
| 	if ((err = namede(fs, path, &de)))
 | |
| 		goto out;
 | |
| 
 | |
| 	clus = stclus(fs->fatsz, de);
 | |
| 	size = getulong(de->deFileSize);
 | |
| 
 | |
| 	if ((!(de->deAttributes & ATTR_DIRECTORY) && (!clus != !size)) ||
 | |
| 	    ((de->deAttributes & ATTR_DIRECTORY) && size) ||
 | |
| 	    (clus && !okclus(fs, clus))) {
 | |
| 		err = EINVAL;
 | |
| 		goto out;
 | |
| 	}
 | |
| 
 | |
| 	f = alloc(sizeof(DOS_FILE));
 | |
| #ifdef BOOTXX
 | |
| 	/* due to __internal_memset_ causing all sorts of register spillage
 | |
| 	   (and being completely unoptimized for zeroing small amounts of
 | |
| 	   memory), if we hand-initialize the remaining members of f to zero,
 | |
| 	   the code size drops 68 bytes. This makes no sense, admittedly. */
 | |
| 	f->offset = 0;
 | |
| 	f->c = 0;
 | |
| #else
 | |
| 	(void)memset(f, 0, sizeof(DOS_FILE));
 | |
| #endif
 | |
| 	f->fs = fs;
 | |
| 	fs->links++;
 | |
| 	f->de = *de;
 | |
| 	fd->f_fsdata = (void *)f;
 | |
| 	fsmod = "msdos";
 | |
| 
 | |
| out:
 | |
| 	return err;
 | |
| }
 | |
| 
 | |
| /*
 | |
|  * Read from file
 | |
|  */
 | |
| __compactcall int
 | |
| dosfs_read(struct open_file *fd, void *vbuf, size_t nbyte, size_t *resid)
 | |
| {
 | |
| 	off_t   size;
 | |
| 	u_int8_t *buf = vbuf;
 | |
| 	u_int   nb, off, clus, c, cnt, n;
 | |
| 	DOS_FILE *f = (DOS_FILE *)fd->f_fsdata;
 | |
| 	int     err = 0;
 | |
| 
 | |
| 	nb = (u_int) nbyte;
 | |
| 	if ((size = fsize(f->fs, &f->de)) == -1)
 | |
| 		return EINVAL;
 | |
| 	if (nb > (n = size - f->offset))
 | |
| 		nb = n;
 | |
| 	off = f->offset;
 | |
| 	if ((clus = stclus(f->fs->fatsz, &f->de)))
 | |
| 		off &= f->fs->bsize - 1;
 | |
| 	c = f->c;
 | |
| 	cnt = nb;
 | |
| 	while (cnt) {
 | |
| 		n = 0;
 | |
| 		if (!c) {
 | |
| 			if ((c = clus))
 | |
| 				n = bytblk(f->fs, f->offset);
 | |
| 		} else if (!off) {
 | |
| 			n++;
 | |
| 		}
 | |
| 		while (n--) {
 | |
| 			if ((err = fatget(f->fs, &c)))
 | |
| 				goto out;
 | |
| 			if (!okclus(f->fs, c)) {
 | |
| 				err = EINVAL;
 | |
| 				goto out;
 | |
| 			}
 | |
| 		}
 | |
| 		if (!clus || (n = f->fs->bsize - off) > cnt)
 | |
| 			n = cnt;
 | |
| 		if ((err = ioread(f->fs, (c ? blkoff(f->fs, c) :
 | |
| 				secbyt(f->fs->lsndir)) + off,
 | |
| 			    buf, n)))
 | |
| 			goto out;
 | |
| 		f->offset += n;
 | |
| 		f->c = c;
 | |
| 		off = 0;
 | |
| 		buf += n;
 | |
| 		cnt -= n;
 | |
| 	}
 | |
| out:
 | |
| 	if (resid)
 | |
| 		*resid = nbyte - nb + cnt;
 | |
| 	return err;
 | |
| }
 | |
| 
 | |
| #ifndef LIBSA_NO_FS_WRITE
 | |
| /*
 | |
|  * Not implemented.
 | |
|  */
 | |
| __compactcall int
 | |
| dosfs_write(struct open_file *fd, void *start, size_t size, size_t *resid)
 | |
| {
 | |
| 
 | |
| 	return EROFS;
 | |
| }
 | |
| #endif /* !LIBSA_NO_FS_WRITE */
 | |
| 
 | |
| #ifndef LIBSA_NO_FS_SEEK
 | |
| /*
 | |
|  * Reposition within file
 | |
|  */
 | |
| __compactcall off_t
 | |
| dosfs_seek(struct open_file *fd, off_t offset, int whence)
 | |
| {
 | |
| 	off_t   off;
 | |
| 	u_int   size;
 | |
| 	DOS_FILE *f = (DOS_FILE *)fd->f_fsdata;
 | |
| 
 | |
| 	size = getulong(f->de.deFileSize);
 | |
| 	switch (whence) {
 | |
| 	case SEEK_SET:
 | |
| 		off = 0;
 | |
| 		break;
 | |
| 	case SEEK_CUR:
 | |
| 		off = f->offset;
 | |
| 		break;
 | |
| 	case SEEK_END:
 | |
| 		off = size;
 | |
| 		break;
 | |
| 	default:
 | |
| 		return -1;
 | |
| 	}
 | |
| 	off += offset;
 | |
| 	if (off < 0 || off > size)
 | |
| 		return -1;
 | |
| 	f->offset = (u_int) off;
 | |
| 	f->c = 0;
 | |
| 	return off;
 | |
| }
 | |
| #endif /* !LIBSA_NO_FS_SEEK */
 | |
| 
 | |
| #ifndef LIBSA_NO_FS_CLOSE
 | |
| /*
 | |
|  * Close open file
 | |
|  */
 | |
| __compactcall int
 | |
| dosfs_close(struct open_file *fd)
 | |
| {
 | |
| 	DOS_FILE *f = (DOS_FILE *)fd->f_fsdata;
 | |
| 	DOS_FS *fs = f->fs;
 | |
| 
 | |
| 	f->fs->links--;
 | |
| 	dealloc(f, sizeof(DOS_FILE));
 | |
| 	dos_unmount(fs);
 | |
| 	return 0;
 | |
| }
 | |
| #endif /* !LIBSA_NO_FS_CLOSE */
 | |
| 
 | |
| /*
 | |
|  * Return some stat information on a file.
 | |
|  */
 | |
| __compactcall int
 | |
| dosfs_stat(struct open_file *fd, struct stat *sb)
 | |
| {
 | |
| 	DOS_FILE *f = (DOS_FILE *)fd->f_fsdata;
 | |
| 
 | |
| 	/* only important stuff */
 | |
| 	sb->st_mode = (f->de.deAttributes & ATTR_DIRECTORY) ?
 | |
| 	    (S_IFDIR | 0555) : (S_IFREG | 0444);
 | |
| 	sb->st_nlink = 1;
 | |
| 	sb->st_uid = 0;
 | |
| 	sb->st_gid = 0;
 | |
| 	if ((sb->st_size = fsize(f->fs, &f->de)) == -1)
 | |
| 		return EINVAL;
 | |
| 	return 0;
 | |
| }
 | |
| 
 | |
| #if defined(LIBSA_ENABLE_LS_OP)
 | |
| __compactcall void
 | |
| dosfs_ls(struct open_file *f, const char *pattern,
 | |
| 		void (*funcp)(char* arg), char* path)
 | |
| {
 | |
| 	printf("Currently ls command is unsupported by dosfs\n");
 | |
| 	return;
 | |
| }
 | |
| #endif
 | |
| 
 | |
| /*
 | |
|  * Parse DOS boot sector
 | |
|  */
 | |
| static int
 | |
| parsebs(DOS_FS *fs, DOS_BS *bs)
 | |
| {
 | |
| 	u_int   sc;
 | |
| 
 | |
| 	if ((bs->jmp[0] != 0x69 &&
 | |
| 		bs->jmp[0] != 0xe9 &&
 | |
| 		(bs->jmp[0] != 0xeb || bs->jmp[2] != 0x90)) ||
 | |
| 	    bs->bpb.bpbMedia < 0xf0)
 | |
| 		return EINVAL;
 | |
| 	if (getushort(bs->bpb.bpbBytesPerSec) != SECSIZ)
 | |
| 		return EINVAL;
 | |
| 	if (!(fs->spc = bs->bpb.bpbSecPerClust) || fs->spc & (fs->spc - 1))
 | |
| 		return EINVAL;
 | |
| 	fs->bsize = secbyt(fs->spc);
 | |
| 	fs->bshift = ffs(fs->bsize) - 1;
 | |
| 	if ((fs->spf = getushort(bs->bpb.bpbFATsecs))) {
 | |
| 		if (bs->bpb.bpbFATs != 2)
 | |
| 			return EINVAL;
 | |
| 		if (!(fs->dirents = getushort(bs->bpb.bpbRootDirEnts)))
 | |
| 			return EINVAL;
 | |
| 	} else {
 | |
| 		if (!(fs->spf = getulong(bs->bpb.bpbBigFATsecs)))
 | |
| 			return EINVAL;
 | |
| 		if (!bs->bpb.bpbFATs || bs->bpb.bpbFATs > 16)
 | |
| 			return EINVAL;
 | |
| 		if ((fs->rdcl = getulong(bs->bpb.bpbRootClust)) < LOCLUS)
 | |
| 			return EINVAL;
 | |
| 	}
 | |
| 	if (!(fs->lsnfat = getushort(bs->bpb.bpbResSectors)))
 | |
| 		return EINVAL;
 | |
| 	fs->lsndir = fs->lsnfat + fs->spf * bs->bpb.bpbFATs;
 | |
| 	fs->lsndta = fs->lsndir + entsec(fs->dirents);
 | |
| 	if (!(sc = getushort(bs->bpb.bpbSectors)) &&
 | |
| 	    !(sc = getulong(bs->bpb.bpbHugeSectors)))
 | |
| 		return EINVAL;
 | |
| 	if (fs->lsndta > sc)
 | |
| 		return EINVAL;
 | |
| 	if ((fs->xclus = secblk(fs, sc - fs->lsndta) + 1) < LOCLUS)
 | |
| 		return EINVAL;
 | |
| 	fs->fatsz = fs->dirents ? fs->xclus < 0xff6 ? 12 : 16 : 32;
 | |
| 	sc = (secbyt(fs->spf) << 1) / (fs->fatsz >> 2) - 1;
 | |
| 	if (fs->xclus > sc)
 | |
| 		fs->xclus = sc;
 | |
| 	return 0;
 | |
| }
 | |
| 
 | |
| /*
 | |
|  * Return directory entry from path
 | |
|  */
 | |
| static int
 | |
| namede(DOS_FS *fs, const char *path, const struct direntry **dep)
 | |
| {
 | |
| 	char    name[256];
 | |
| 	const struct direntry *de;
 | |
| 	char   *s;
 | |
| 	size_t  n;
 | |
| 	int     err;
 | |
| 
 | |
| 	err = 0;
 | |
| 	de = dot;
 | |
| 	if (*path == '/')
 | |
| 		path++;
 | |
| 	while (*path) {
 | |
| 		if (!(s = strchr(path, '/')))
 | |
| 			s = strchr(path, 0);
 | |
| 		if ((n = s - path) > 255)
 | |
| 			return ENAMETOOLONG;
 | |
| 		memcpy(name, path, n);
 | |
| 		name[n] = 0;
 | |
| 		path = s;
 | |
| 		if (!(de->deAttributes & ATTR_DIRECTORY))
 | |
| 			return ENOTDIR;
 | |
| 		if ((err = lookup(fs, stclus(fs->fatsz, de), name, &de)))
 | |
| 			return err;
 | |
| 		if (*path == '/')
 | |
| 			path++;
 | |
| 	}
 | |
| 	*dep = de;
 | |
| 	return 0;
 | |
| }
 | |
| 
 | |
| /*
 | |
|  * Lookup path segment
 | |
|  */
 | |
| static int
 | |
| lookup(DOS_FS *fs, u_int clus, const char *name, const struct direntry **dep)
 | |
| {
 | |
| 	static DOS_DIR *dir = NULL;
 | |
| 	u_char  lfn[261];
 | |
| 	u_char  sfn[13];
 | |
| 	u_int   nsec, lsec, xdn, chk, sec, ent, x;
 | |
| 	int     err = 0, ok, i;
 | |
| 
 | |
| 	if (!clus)
 | |
| 		for (ent = 0; ent < 2; ent++)
 | |
| 			if (!strcasecmp(name, dotstr[ent])) {
 | |
| 				*dep = dot + ent;
 | |
| 				return 0;
 | |
| 			}
 | |
| 
 | |
| 	if (dir == NULL) {
 | |
| 		dir = alloc(sizeof(DOS_DIR) * DEPSEC);
 | |
| 		if (dir == NULL)
 | |
| 			return ENOMEM;
 | |
| 	}
 | |
| 
 | |
| 	if (!clus && fs->fatsz == 32)
 | |
| 		clus = fs->rdcl;
 | |
| 	nsec = !clus ? entsec(fs->dirents) : fs->spc;
 | |
| 	lsec = 0;
 | |
| 	xdn = chk = 0;
 | |
| 	for (;;) {
 | |
| 		if (!clus && !lsec)
 | |
| 			lsec = fs->lsndir;
 | |
| 		else if (okclus(fs, clus))
 | |
| 			lsec = blklsn(fs, clus);
 | |
| 		else {
 | |
| 			err = EINVAL;
 | |
| 			goto out;
 | |
| 		}
 | |
| 		for (sec = 0; sec < nsec; sec++) {
 | |
| 			if ((err = ioget(fs->fd, lsec + sec, dir, 1)))
 | |
| 				goto out;
 | |
| 			for (ent = 0; ent < DEPSEC; ent++) {
 | |
| 				if (!*dir[ent].de.deName) {
 | |
| 					err = ENOENT;
 | |
| 					goto out;
 | |
| 				}
 | |
| 				if (*dir[ent].de.deName != 0xe5) {
 | |
| 					if (dir[ent].de.deAttributes ==
 | |
| 					    ATTR_WIN95) {
 | |
| 						x = dir[ent].xde.weCnt;
 | |
| 						if (x & WIN_LAST ||
 | |
| 						    (x + 1 == xdn &&
 | |
| 						     dir[ent].xde.weChksum ==
 | |
| 						     chk)) {
 | |
| 							if (x & WIN_LAST) {
 | |
| 								chk = dir[ent].xde.weChksum;
 | |
| 								x &= WIN_CNT;
 | |
| 							}
 | |
| 							if (x >= 1 && x <= 20) {
 | |
| 								cp_xdnm(lfn, &dir[ent].xde);
 | |
| 								xdn = x;
 | |
| 								continue;
 | |
| 							}
 | |
| 						}
 | |
| 					} else if (!(dir[ent].de.deAttributes &
 | |
| 						     ATTR_VOLUME)) {
 | |
| 						if ((ok = xdn == 1)) {
 | |
| 							for (x = 0, i = 0;
 | |
| 							     i < 11; i++)
 | |
| 								x = ((((x & 1) << 7) | (x >> 1)) +
 | |
| 								    dir[ent].de.deName[i]) & 0xff;
 | |
| 							ok = chk == x &&
 | |
| 							    !strcasecmp(name, (const char *)lfn);
 | |
| 						}
 | |
| 						if (!ok) {
 | |
| 							cp_sfn(sfn, &dir[ent].de);
 | |
| 							ok = !strcasecmp(name, (const char *)sfn);
 | |
| 						}
 | |
| 						if (ok) {
 | |
| 							*dep = &dir[ent].de;
 | |
| 							goto out2;
 | |
| 						}
 | |
| 					}
 | |
| 				}
 | |
| 				xdn = 0;
 | |
| 			}
 | |
| 		}
 | |
| 		if (!clus)
 | |
| 			break;
 | |
| 		if ((err = fatget(fs, &clus)))
 | |
| 			goto out;
 | |
| 		if (fatend(fs->fatsz, clus))
 | |
| 			break;
 | |
| 	}
 | |
| 	err = ENOENT;
 | |
|  out:
 | |
| 	dealloc(dir, sizeof(DOS_DIR) * DEPSEC);
 | |
| 	dir = NULL;
 | |
|  out2:
 | |
| 	return err;
 | |
| }
 | |
| 
 | |
| /*
 | |
|  * Copy name from extended directory entry
 | |
|  */
 | |
| static void
 | |
| cp_xdnm(u_char *lfn, struct winentry *xde)
 | |
| {
 | |
| 	static const struct {
 | |
| 		u_int   off;
 | |
| 		u_int   dim;
 | |
| 	} ix[3] = {
 | |
| 		{ offsetof(struct winentry, wePart1),
 | |
| 		    sizeof(xde->wePart1) / 2 },
 | |
| 		{ offsetof(struct winentry, wePart2),
 | |
| 		    sizeof(xde->wePart2) / 2 },
 | |
| 		{ offsetof(struct winentry, wePart3),
 | |
| 		    sizeof(xde->wePart3) / 2 }
 | |
| 	};
 | |
| 	u_char *p;
 | |
| 	u_int   n, x, c;
 | |
| 
 | |
| 	lfn += 13 * ((xde->weCnt & WIN_CNT) - 1);
 | |
| 	for (n = 0; n < 3; n++)
 | |
| 		for (p = (u_char *)xde + ix[n].off, x = ix[n].dim; x;
 | |
| 		    p += 2, x--) {
 | |
| 			if ((c = getushort(p)) && (c < 32 || c > 127))
 | |
| 				c = '?';
 | |
| 			if (!(*lfn++ = c))
 | |
| 				return;
 | |
| 		}
 | |
| 	if (xde->weCnt & WIN_LAST)
 | |
| 		*lfn = 0;
 | |
| }
 | |
| 
 | |
| /*
 | |
|  * Copy short filename
 | |
|  */
 | |
| static void
 | |
| cp_sfn(u_char *sfn, struct direntry *de)
 | |
| {
 | |
| 	u_char *p;
 | |
| 	int     j, i;
 | |
| 
 | |
| 	p = sfn;
 | |
| 	if (*de->deName != ' ') {
 | |
| 		for (j = 7; de->deName[j] == ' '; j--);
 | |
| 		for (i = 0; i <= j; i++)
 | |
| 			*p++ = de->deName[i];
 | |
| 		if (*de->deExtension != ' ') {
 | |
| 			*p++ = '.';
 | |
| 			for (j = 2; de->deExtension[j] == ' '; j--);
 | |
| 			for (i = 0; i <= j; i++)
 | |
| 				*p++ = de->deExtension[i];
 | |
| 		}
 | |
| 	}
 | |
| 	*p = 0;
 | |
| 	if (*sfn == 5)
 | |
| 		*sfn = 0xe5;
 | |
| }
 | |
| 
 | |
| /*
 | |
|  * Return size of file in bytes
 | |
|  */
 | |
| static  off_t
 | |
| fsize(DOS_FS *fs, struct direntry *de)
 | |
| {
 | |
| 	u_long  size;
 | |
| 	u_int   c;
 | |
| 	int     n;
 | |
| 
 | |
| 	if (!(size = getulong(de->deFileSize)) &&
 | |
| 	    de->deAttributes & ATTR_DIRECTORY) {
 | |
| 		if (!(c = getushort(de->deStartCluster))) {
 | |
| 			size = fs->dirents * sizeof(struct direntry);
 | |
| 		} else {
 | |
| 			if ((n = fatcnt(fs, c)) == -1)
 | |
| 				return n;
 | |
| 			size = blkbyt(fs, n);
 | |
| 		}
 | |
| 	}
 | |
| 	return size;
 | |
| }
 | |
| 
 | |
| /*
 | |
|  * Count number of clusters in chain
 | |
|  */
 | |
| static int
 | |
| fatcnt(DOS_FS *fs, u_int c)
 | |
| {
 | |
| 	int     n;
 | |
| 
 | |
| 	for (n = 0; okclus(fs, c); n++)
 | |
| 		if (fatget(fs, &c))
 | |
| 			return -1;
 | |
| 	return fatend(fs->fatsz, c) ? n : -1;
 | |
| }
 | |
| 
 | |
| /*
 | |
|  * Get next cluster in cluster chain
 | |
|  */
 | |
| static int
 | |
| fatget(DOS_FS *fs, u_int *c)
 | |
| {
 | |
| 	u_char  buf[4];
 | |
| 	u_int   x;
 | |
| 	int     err;
 | |
| 
 | |
| 	err = ioread(fs, secbyt(fs->lsnfat) + fatoff(fs->fatsz, *c), buf,
 | |
| 	    fs->fatsz != 32 ? 2 : 4);
 | |
| 	if (err)
 | |
| 		return err;
 | |
| 	x = fs->fatsz != 32 ? getushort(buf) : getulong(buf);
 | |
| 	*c = fs->fatsz == 12 ? *c & 1 ? x >> 4 : x & 0xfff : x;
 | |
| 	return 0;
 | |
| }
 | |
| 
 | |
| /*
 | |
|  * Is cluster an end-of-chain marker?
 | |
|  */
 | |
| static int
 | |
| fatend(u_int sz, u_int c)
 | |
| {
 | |
| 	return c > (sz == 12 ? 0xff7U : sz == 16 ? 0xfff7U : 0xffffff7);
 | |
| }
 | |
| 
 | |
| /*
 | |
|  * Offset-based I/O primitive
 | |
|  */
 | |
| static int
 | |
| ioread(DOS_FS *fs, u_int offset, void *buf, u_int nbyte)
 | |
| {
 | |
| 	char   *s;
 | |
| 	u_int   off, n;
 | |
| 	int     err;
 | |
| 
 | |
| 	s = buf;
 | |
| 	if ((off = offset & (SECSIZ - 1))) {
 | |
| 		offset -= off;
 | |
| 		if ((err = iobuf(fs, bytsec(offset))))
 | |
| 			return err;
 | |
| 		offset += SECSIZ;
 | |
| 		if ((n = SECSIZ - off) > nbyte)
 | |
| 			n = nbyte;
 | |
| 		memcpy(s, fs->buf + off, n);
 | |
| 		s += n;
 | |
| 		nbyte -= n;
 | |
| 	}
 | |
| 	n = nbyte & (SECSIZ - 1);
 | |
| 	if (nbyte -= n) {
 | |
| 		if ((err = ioget(fs->fd, bytsec(offset), s, bytsec(nbyte))))
 | |
| 			return err;
 | |
| 		offset += nbyte;
 | |
| 		s += nbyte;
 | |
| 	}
 | |
| 	if (n) {
 | |
| 		if ((err = iobuf(fs, bytsec(offset))))
 | |
| 			return err;
 | |
| 		memcpy(s, fs->buf, n);
 | |
| 	}
 | |
| 	return 0;
 | |
| }
 | |
| 
 | |
| /*
 | |
|  * Buffered sector-based I/O primitive
 | |
|  */
 | |
| static int
 | |
| iobuf(DOS_FS *fs, u_int lsec)
 | |
| {
 | |
| 	int     err;
 | |
| 
 | |
| 	if (fs->bufsec != lsec) {
 | |
| 		if ((err = ioget(fs->fd, lsec, fs->buf, 1)))
 | |
| 			return err;
 | |
| 		fs->bufsec = lsec;
 | |
| 	}
 | |
| 	return 0;
 | |
| }
 | |
| 
 | |
| /*
 | |
|  * Sector-based I/O primitive
 | |
|  */
 | |
| static int
 | |
| ioget(struct open_file *fd, u_int lsec, void *buf, u_int nsec)
 | |
| {
 | |
| 	size_t rsize;
 | |
| 	int err;
 | |
| 
 | |
| #ifndef LIBSA_NO_TWIDDLE
 | |
| 	twiddle();
 | |
| #endif
 | |
| 	err = DEV_STRATEGY(fd->f_dev)(fd->f_devdata, F_READ, lsec,
 | |
| 	    secbyt(nsec), buf, &rsize);
 | |
| 	return err;
 | |
| }
 |