| File: | src/usr.sbin/makefs/msdos/msdosfs_denode.c |
| Warning: | line 178, column 5 Value stored to 'error' is never read |
Press '?' to see keyboard shortcuts
Keyboard shortcuts:
| 1 | /* $OpenBSD: msdosfs_denode.c,v 1.7 2021/10/06 00:40:41 deraadt Exp $ */ |
| 2 | /* $NetBSD: msdosfs_denode.c,v 1.7 2015/03/29 05:52:59 agc Exp $ */ |
| 3 | |
| 4 | /*- |
| 5 | * Copyright (C) 1994, 1995, 1997 Wolfgang Solfrank. |
| 6 | * Copyright (C) 1994, 1995, 1997 TooLs GmbH. |
| 7 | * All rights reserved. |
| 8 | * Original code by Paul Popelka (paulp@uts.amdahl.com) (see below). |
| 9 | * |
| 10 | * Redistribution and use in source and binary forms, with or without |
| 11 | * modification, are permitted provided that the following conditions |
| 12 | * are met: |
| 13 | * 1. Redistributions of source code must retain the above copyright |
| 14 | * notice, this list of conditions and the following disclaimer. |
| 15 | * 2. Redistributions in binary form must reproduce the above copyright |
| 16 | * notice, this list of conditions and the following disclaimer in the |
| 17 | * documentation and/or other materials provided with the distribution. |
| 18 | * 3. All advertising materials mentioning features or use of this software |
| 19 | * must display the following acknowledgement: |
| 20 | * This product includes software developed by TooLs GmbH. |
| 21 | * 4. The name of TooLs GmbH may not be used to endorse or promote products |
| 22 | * derived from this software without specific prior written permission. |
| 23 | * |
| 24 | * THIS SOFTWARE IS PROVIDED BY TOOLS GMBH ``AS IS'' AND ANY EXPRESS OR |
| 25 | * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES |
| 26 | * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. |
| 27 | * IN NO EVENT SHALL TOOLS GMBH BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, |
| 28 | * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, |
| 29 | * PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; |
| 30 | * OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, |
| 31 | * WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR |
| 32 | * OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF |
| 33 | * ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. |
| 34 | */ |
| 35 | /* |
| 36 | * Written by Paul Popelka (paulp@uts.amdahl.com) |
| 37 | * |
| 38 | * You can do anything you want with this software, just don't say you wrote |
| 39 | * it, and don't remove this notice. |
| 40 | * |
| 41 | * This software is provided "as is". |
| 42 | * |
| 43 | * The author supplies this software to be publicly redistributed on the |
| 44 | * understanding that the author is not responsible for the correct |
| 45 | * functioning of this software in any circumstances and is not liable for |
| 46 | * any damages caused by this software. |
| 47 | * |
| 48 | * October 1992 |
| 49 | */ |
| 50 | |
| 51 | |
| 52 | #include "ffs/buf.h" |
| 53 | |
| 54 | #include <msdosfs/bpb.h> |
| 55 | #include "msdos/msdosfsmount.h" |
| 56 | #include "msdos/direntry.h" |
| 57 | #include "msdos/denode.h" |
| 58 | #include "msdos/fat.h" |
| 59 | |
| 60 | #include <util.h> |
| 61 | |
| 62 | #include "makefs.h" |
| 63 | |
| 64 | /* |
| 65 | * If deget() succeeds it returns with the gotten denode locked(). |
| 66 | * |
| 67 | * pmp - address of msdosfsmount structure of the filesystem containing |
| 68 | * the denode of interest. The pm_dev field and the address of |
| 69 | * the msdosfsmount structure are used. |
| 70 | * dirclust - which cluster bp contains, if dirclust is 0 (root directory) |
| 71 | * diroffset is relative to the beginning of the root directory, |
| 72 | * otherwise it is cluster relative. |
| 73 | * diroffset - offset past begin of cluster of denode we want |
| 74 | * depp - returns the address of the gotten denode. |
| 75 | */ |
| 76 | int |
| 77 | deget(struct msdosfsmount *pmp, u_long dirclust, u_long diroffset, |
| 78 | struct denode **depp) |
| 79 | /* pmp: so we know the maj/min number */ |
| 80 | /* dirclust: cluster this dir entry came from */ |
| 81 | /* diroffset: index of entry within the cluster */ |
| 82 | /* depp: returns the addr of the gotten denode */ |
| 83 | { |
| 84 | int error; |
| 85 | struct direntry *direntptr; |
| 86 | struct denode *ldep; |
| 87 | struct mkfsbuf *bp; |
| 88 | |
| 89 | #ifdef MSDOSFS_DEBUG |
| 90 | printf("deget(pmp %p, dirclust %lu, diroffset %lx, depp %p)\n", |
| 91 | pmp, dirclust, diroffset, depp); |
| 92 | #endif |
| 93 | |
| 94 | /* |
| 95 | * On FAT32 filesystems, root is a (more or less) normal |
| 96 | * directory |
| 97 | */ |
| 98 | if (FAT32(pmp)(pmp->pm_fatmask == 0x0fffffff) && dirclust == MSDOSFSROOT0) |
| 99 | dirclust = pmp->pm_rootdirblk; |
| 100 | |
| 101 | ldep = ecalloc(1, sizeof(*ldep)); |
| 102 | ldep->de_mkfsvnode = NULL((void *)0); |
| 103 | ldep->de_flag = 0; |
| 104 | ldep->de_devvp = 0; |
| 105 | ldep->de_lockf = 0; |
| 106 | ldep->de_dev = pmp->pm_dev; |
| 107 | ldep->de_dirclustde_key.dk_dirclust = dirclust; |
| 108 | ldep->de_diroffsetde_key.dk_diroffset = diroffset; |
| 109 | ldep->de_pmp = pmp; |
| 110 | ldep->de_devvp = pmp->pm_devvp; |
| 111 | ldep->de_refcnt = 1; |
| 112 | fc_purge(ldep, 0); |
| 113 | /* |
| 114 | * Copy the directory entry into the denode area of the mkfsvnode. |
| 115 | */ |
| 116 | if ((dirclust == MSDOSFSROOT0 |
| 117 | || (FAT32(pmp)(pmp->pm_fatmask == 0x0fffffff) && dirclust == pmp->pm_rootdirblk)) |
| 118 | && diroffset == MSDOSFSROOT_OFS0x1fffffff) { |
| 119 | /* |
| 120 | * Directory entry for the root directory. There isn't one, |
| 121 | * so we manufacture one. We should probably rummage |
| 122 | * through the root directory and find a label entry (if it |
| 123 | * exists), and then use the time and date from that entry |
| 124 | * as the time and date for the root denode. |
| 125 | */ |
| 126 | ldep->de_mkfsvnode = (struct mkfsvnode *)-1; |
| 127 | |
| 128 | ldep->de_Attributes = ATTR_DIRECTORY0x10; |
| 129 | if (FAT32(pmp)(pmp->pm_fatmask == 0x0fffffff)) |
| 130 | ldep->de_StartCluster = pmp->pm_rootdirblk; |
| 131 | /* de_FileSize will be filled in further down */ |
| 132 | else { |
| 133 | ldep->de_StartCluster = MSDOSFSROOT0; |
| 134 | ldep->de_FileSize = pmp->pm_rootdirsize * pmp->pm_BytesPerSecpm_bpb.bpbBytesPerSec; |
| 135 | } |
| 136 | /* |
| 137 | * fill in time and date so that dos2unixtime() doesn't |
| 138 | * spit up when called from msdosfs_getattr() with root |
| 139 | * denode |
| 140 | */ |
| 141 | ldep->de_CHun = 0; |
| 142 | ldep->de_CTime = 0x0000; /* 00:00:00 */ |
| 143 | ldep->de_CDate = (0 << DD_YEAR_SHIFT9) | (1 << DD_MONTH_SHIFT5) |
| 144 | | (1 << DD_DAY_SHIFT0); |
| 145 | /* Jan 1, 1980 */ |
| 146 | ldep->de_ADate = ldep->de_CDate; |
| 147 | ldep->de_MTime = ldep->de_CTime; |
| 148 | ldep->de_MDate = ldep->de_CDate; |
| 149 | /* leave the other fields as garbage */ |
| 150 | } else { |
| 151 | error = readep(pmp, dirclust, diroffset, &bp, &direntptr); |
| 152 | if (error) { |
| 153 | ldep->de_devvp = NULL((void *)0); |
| 154 | ldep->de_Name[0] = SLOT_DELETED0xe5; |
| 155 | return (error); |
| 156 | } |
| 157 | DE_INTERNALIZE(ldep, direntptr)(memcpy((ldep)->de_Name, (direntptr)->deName, 11), (ldep )->de_Attributes = (direntptr)->deAttributes, (ldep)-> de_CHun = (direntptr)->deCTimeHundredth, (ldep)->de_CTime = *((u_int16_t *)((direntptr)->deCTime)), (ldep)->de_CDate = *((u_int16_t *)((direntptr)->deCDate)), (ldep)->de_ADate = *((u_int16_t *)((direntptr)->deADate)), (ldep)->de_MTime = *((u_int16_t *)((direntptr)->deMTime)), (ldep)->de_MDate = *((u_int16_t *)((direntptr)->deMDate)), (ldep)->de_StartCluster = *((u_int16_t *)((direntptr)->deStartCluster)), (ldep)-> de_FileSize = *((u_int32_t *)((direntptr)->deFileSize)), ( ((ldep)->de_pmp->pm_fatmask == 0x0fffffff) ? (((ldep))-> de_StartCluster |= *((u_int16_t *)(((direntptr))->deHighClust )) << 16) : 0)); |
| 158 | brelse(bp, 0); |
| 159 | } |
| 160 | |
| 161 | /* |
| 162 | * Fill in a few fields of the mkfsvnode and finish filling in the |
| 163 | * denode. Then return the address of the found denode. |
| 164 | */ |
| 165 | if (ldep->de_Attributes & ATTR_DIRECTORY0x10) { |
| 166 | /* |
| 167 | * Since DOS directory entries that describe directories |
| 168 | * have 0 in the filesize field, we take this opportunity |
| 169 | * to find out the length of the directory and plug it into |
| 170 | * the denode structure. |
| 171 | */ |
| 172 | u_long size; |
| 173 | |
| 174 | if (ldep->de_StartCluster != MSDOSFSROOT0) { |
| 175 | error = pcbmap(ldep, CLUST_END0xffffffff, 0, &size, 0); |
| 176 | if (error == E2BIG7) { |
| 177 | ldep->de_FileSize = de_cn2off(pmp, size)((size) << (pmp)->pm_cnshift); |
| 178 | error = 0; |
Value stored to 'error' is never read | |
| 179 | } else |
| 180 | printf("deget(): pcbmap returned %d\n", error); |
| 181 | } |
| 182 | } |
| 183 | *depp = ldep; |
| 184 | return (0); |
| 185 | } |
| 186 | |
| 187 | /* |
| 188 | * Truncate the file described by dep to the length specified by length. |
| 189 | */ |
| 190 | int |
| 191 | detrunc(struct denode *dep, u_long length, int flags) |
| 192 | { |
| 193 | int error; |
| 194 | int allerror = 0; |
| 195 | u_long eofentry; |
| 196 | u_long chaintofree = 0; |
| 197 | daddr_t bn, lastblock; |
| 198 | int boff; |
| 199 | int isadir = dep->de_Attributes & ATTR_DIRECTORY0x10; |
| 200 | struct mkfsbuf *bp; |
| 201 | struct msdosfsmount *pmp = dep->de_pmp; |
| 202 | |
| 203 | #ifdef MSDOSFS_DEBUG |
| 204 | printf("detrunc(): file %s, length %lu, flags %x\n", dep->de_Name, length, flags); |
| 205 | #endif |
| 206 | |
| 207 | /* |
| 208 | * Disallow attempts to truncate the root directory since it is of |
| 209 | * fixed size. That's just the way dos filesystems are. We use |
| 210 | * the VROOT bit in the mkfsvnode because checking for the directory |
| 211 | * bit and a startcluster of 0 in the denode is not adequate to |
| 212 | * recognize the root directory at this point in a file or |
| 213 | * directory's life. |
| 214 | */ |
| 215 | if (dep->de_mkfsvnode != NULL((void *)0) && !FAT32(pmp)(pmp->pm_fatmask == 0x0fffffff)) { |
| 216 | printf("detrunc(): can't truncate root directory, clust %ld, offset %ld\n", |
| 217 | dep->de_dirclustde_key.dk_dirclust, dep->de_diroffsetde_key.dk_diroffset); |
| 218 | return (EINVAL22); |
| 219 | } |
| 220 | |
| 221 | if (dep->de_FileSize < length) |
| 222 | return (deextend(dep, length)); |
| 223 | lastblock = de_clcount(pmp, length)(((length) + (pmp)->pm_bpcluster - 1) >> (pmp)->pm_cnshift ) - 1; |
| 224 | |
| 225 | /* |
| 226 | * If the desired length is 0 then remember the starting cluster of |
| 227 | * the file and set the StartCluster field in the directory entry |
| 228 | * to 0. If the desired length is not zero, then get the number of |
| 229 | * the last cluster in the shortened file. Then get the number of |
| 230 | * the first cluster in the part of the file that is to be freed. |
| 231 | * Then set the next cluster pointer in the last cluster of the |
| 232 | * file to CLUST_EOFE. |
| 233 | */ |
| 234 | if (length == 0) { |
| 235 | chaintofree = dep->de_StartCluster; |
| 236 | dep->de_StartCluster = 0; |
| 237 | eofentry = ~0; |
| 238 | } else { |
| 239 | error = pcbmap(dep, lastblock, 0, &eofentry, 0); |
| 240 | if (error) { |
| 241 | #ifdef MSDOSFS_DEBUG |
| 242 | printf("detrunc(): pcbmap fails %d\n", error); |
| 243 | #endif |
| 244 | return (error); |
| 245 | } |
| 246 | } |
| 247 | |
| 248 | /* |
| 249 | * If the new length is not a multiple of the cluster size then we |
| 250 | * must zero the tail end of the new last cluster in case it |
| 251 | * becomes part of the file again because of a seek. |
| 252 | */ |
| 253 | if ((boff = length & pmp->pm_crbomask) != 0) { |
| 254 | if (isadir) { |
| 255 | bn = cntobn(pmp, eofentry)((((eofentry)-2) << (((pmp))->pm_cnshift - ((pmp))-> pm_bnshift)) + (pmp)->pm_firstcluster); |
| 256 | error = bread(pmp->pm_devvp, de_bn2kb(pmp, bn)((bn) << ((pmp)->pm_bnshift - 9)), |
| 257 | pmp->pm_bpcluster, B_MODIFY0, &bp); |
| 258 | if (error) { |
| 259 | #ifdef MSDOSFS_DEBUG |
| 260 | printf("detrunc(): bread fails %d\n", error); |
| 261 | #endif |
| 262 | return (error); |
| 263 | } |
| 264 | memset((char *)bp->b_data + boff, 0, |
| 265 | pmp->pm_bpcluster - boff); |
| 266 | if (flags & IO_SYNC1) |
| 267 | bwrite(bp); |
| 268 | else |
| 269 | bdwrite(bp)bwrite(bp); |
| 270 | } |
| 271 | } |
| 272 | |
| 273 | /* |
| 274 | * Write out the updated directory entry. Even if the update fails |
| 275 | * we free the trailing clusters. |
| 276 | */ |
| 277 | dep->de_FileSize = length; |
| 278 | if (!isadir) |
| 279 | dep->de_flag |= DE_UPDATE0x0001|DE_MODIFIED0x0008; |
| 280 | #ifdef MSDOSFS_DEBUG |
| 281 | printf("detrunc(): allerror %d, eofentry %lu\n", |
| 282 | allerror, eofentry); |
| 283 | #endif |
| 284 | |
| 285 | /* |
| 286 | * If we need to break the cluster chain for the file then do it |
| 287 | * now. |
| 288 | */ |
| 289 | if (eofentry != (u_long)~0) { |
| 290 | error = fatentry(FAT_GET_AND_SET(0x0001 | 0x0002), pmp, eofentry, |
| 291 | &chaintofree, CLUST_EOFE0xffffffff); |
| 292 | if (error) { |
| 293 | #ifdef MSDOSFS_DEBUG |
| 294 | printf("detrunc(): fatentry errors %d\n", error); |
| 295 | #endif |
| 296 | return (error); |
| 297 | } |
| 298 | } |
| 299 | |
| 300 | /* |
| 301 | * Now free the clusters removed from the file because of the |
| 302 | * truncation. |
| 303 | */ |
| 304 | if (chaintofree != 0 && !MSDOSFSEOF(chaintofree, pmp->pm_fatmask)(((chaintofree) & 0xfffffff8) == (0xfffffff8 & (pmp-> pm_fatmask)))) |
| 305 | freeclusterchain(pmp, chaintofree); |
| 306 | |
| 307 | return (allerror); |
| 308 | } |
| 309 | |
| 310 | /* |
| 311 | * Extend the file described by dep to length specified by length. |
| 312 | */ |
| 313 | int |
| 314 | deextend(struct denode *dep, u_long length) |
| 315 | { |
| 316 | struct msdosfsmount *pmp = dep->de_pmp; |
| 317 | u_long count; |
| 318 | int error; |
| 319 | |
| 320 | /* |
| 321 | * The root of a DOS filesystem cannot be extended. |
| 322 | */ |
| 323 | if (dep->de_mkfsvnode != NULL((void *)0) && !FAT32(pmp)(pmp->pm_fatmask == 0x0fffffff)) |
| 324 | return EINVAL22; |
| 325 | |
| 326 | /* |
| 327 | * Directories cannot be extended. |
| 328 | */ |
| 329 | if (dep->de_Attributes & ATTR_DIRECTORY0x10) |
| 330 | return EISDIR21; |
| 331 | |
| 332 | if (length <= dep->de_FileSize) |
| 333 | return E2BIG7; |
| 334 | |
| 335 | /* |
| 336 | * Compute the number of clusters to allocate. |
| 337 | */ |
| 338 | count = de_clcount(pmp, length)(((length) + (pmp)->pm_bpcluster - 1) >> (pmp)->pm_cnshift ) - de_clcount(pmp, dep->de_FileSize)(((dep->de_FileSize) + (pmp)->pm_bpcluster - 1) >> (pmp)->pm_cnshift); |
| 339 | if (count > 0) { |
| 340 | if (count > pmp->pm_freeclustercount) |
| 341 | return (ENOSPC28); |
| 342 | error = extendfile(dep, count, NULL((void *)0), NULL((void *)0), DE_CLEAR1); |
| 343 | if (error) { |
| 344 | /* truncate the added clusters away again */ |
| 345 | (void) detrunc(dep, dep->de_FileSize, 0); |
| 346 | return (error); |
| 347 | } |
| 348 | } |
| 349 | |
| 350 | /* |
| 351 | * Zero extend file range; ubc_zerorange() uses ubc_alloc() and a |
| 352 | * memset(); we set the write size so ubc won't read in file data that |
| 353 | * is zero'd later. |
| 354 | */ |
| 355 | dep->de_FileSize = length; |
| 356 | dep->de_flag |= DE_UPDATE0x0001|DE_MODIFIED0x0008; |
| 357 | return 0; |
| 358 | } |