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IABSD.fr/src/sbin/dump/traverse.c
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- sbin/dump/traverse.c
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/* $OpenBSD: traverse.c,v 1.43 2024/09/15 07:14:58 jsg Exp $ */ /* $NetBSD: traverse.c,v 1.17 1997/06/05 11:13:27 lukem Exp $ */ /*- * Copyright (c) 1980, 1988, 1991, 1993 * The Regents of the University of California. 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. Neither the name of the University nor the names of its contributors * may be used to endorse or promote products derived from this software * without specific prior written permission. * * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``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 REGENTS OR CONTRIBUTORS 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. */ #include <sys/param.h> /* MAXBSIZE DEV_BSIZE dbtob */ #include <sys/time.h> #include <sys/stat.h> #include <sys/disklabel.h> #include <ufs/ffs/fs.h> #include <ufs/ufs/dir.h> #include <ufs/ufs/dinode.h> #include <protocols/dumprestore.h> #include <ctype.h> #include <errno.h> #include <fts.h> #include <stdio.h> #include <stdlib.h> #include <string.h> #include <unistd.h> #include <limits.h> #include "dump.h" extern struct disklabel lab; union dinode { struct ufs1_dinode dp1; struct ufs2_dinode dp2; }; #define DIP(dp, field) \ ((sblock->fs_magic == FS_UFS1_MAGIC) ? \ (dp)->dp1.field : (dp)->dp2.field) #define HASDUMPEDFILE 0x1 #define HASSUBDIRS 0x2 static int dirindir(ino_t, daddr_t, int, off_t *, int64_t *, int); static void dmpindir(ino_t, daddr_t, int, off_t *); static int searchdir(ino_t, daddr_t, long, off_t, int64_t *, int); void fs_mapinodes(ino_t maxino, off_t *tapesize, int *anydirskipped); /* * This is an estimation of the number of TP_BSIZE blocks in the file. * It estimates the number of blocks in files with holes by assuming * that all of the blocks accounted for by di_blocks are data blocks * (when some of the blocks are usually used for indirect pointers); * hence the estimate may be high. */ int64_t blockest(union dinode *dp) { int64_t blkest, sizeest; /* * dp->di_size is the size of the file in bytes. * dp->di_blocks stores the number of sectors actually in the file. * If there are more sectors than the size would indicate, this just * means that there are indirect blocks in the file or unused * sectors in the last file block; we can safely ignore these * (blkest = sizeest below). * If the file is bigger than the number of sectors would indicate, * then the file has holes in it. In this case we must use the * block count to estimate the number of data blocks used, but * we use the actual size for estimating the number of indirect * dump blocks (sizeest vs. blkest in the indirect block * calculation). */ blkest = howmany(dbtob((int64_t)DIP(dp, di_blocks)), TP_BSIZE); sizeest = howmany((int64_t)DIP(dp, di_size), TP_BSIZE); if (blkest > sizeest) blkest = sizeest; if (DIP(dp, di_size) > sblock->fs_bsize * NDADDR) { /* calculate the number of indirect blocks on the dump tape */ blkest += howmany(sizeest - NDADDR * sblock->fs_bsize / TP_BSIZE, TP_NINDIR); } return (blkest + 1); } /* true if "nodump" flag has no effect here, i.e. dumping allowed */ #define CHECKNODUMP(dp) \ (nonodump || (DIP((dp), di_flags) & UF_NODUMP) != UF_NODUMP) /* * Determine if given inode should be dumped */ void mapfileino(ino_t ino, int64_t *tapesize, int *dirskipped) { int mode; union dinode *dp; dp = getino(ino, &mode); if (mode == 0) return; SETINO(ino, usedinomap); if (mode == IFDIR) SETINO(ino, dumpdirmap); if (CHECKNODUMP(dp) && (DIP(dp, di_mtime) >= spcl.c_ddate || DIP(dp, di_ctime) >= spcl.c_ddate)) { SETINO(ino, dumpinomap); if (mode != IFREG && mode != IFDIR && mode != IFLNK) *tapesize += 1; else *tapesize += blockest(dp); return; } if (mode == IFDIR) { if (!CHECKNODUMP(dp)) CLRINO(ino, usedinomap); *dirskipped = 1; } } void fs_mapinodes(ino_t maxino, int64_t *tapesize, int *anydirskipped) { int i, cg, inosused; struct cg *cgp; ino_t ino; if ((cgp = malloc(sblock->fs_cgsize)) == NULL) quit("fs_mapinodes: cannot allocate memory.\n"); for (cg = 0; cg < sblock->fs_ncg; cg++) { ino = cg * (ino_t)sblock->fs_ipg; bread(fsbtodb(sblock, cgtod(sblock, cg)), (char *)cgp, sblock->fs_cgsize); if (sblock->fs_magic == FS_UFS2_MAGIC) inosused = cgp->cg_initediblk; else inosused = sblock->fs_ipg; for (i = 0; i < inosused; i++, ino++) { if (ino < ROOTINO) continue; mapfileino(ino, tapesize, anydirskipped); } } free(cgp); } /* * Dump pass 1. * * Walk the inode list for a filesystem to find all allocated inodes * that have been modified since the previous dump time. Also, find all * the directories in the filesystem. */ int mapfiles(ino_t maxino, int64_t *tapesize, char *disk, char * const *dirv) { int anydirskipped = 0; if (dirv != NULL) { char curdir[PATH_MAX]; FTS *dirh; FTSENT *entry; int d; if (getcwd(curdir, sizeof(curdir)) == NULL) { msg("Can't determine cwd: %s\n", strerror(errno)); dumpabort(0); } if ((dirh = fts_open(dirv, FTS_PHYSICAL|FTS_SEEDOT|FTS_XDEV, NULL)) == NULL) { msg("fts_open failed: %s\n", strerror(errno)); dumpabort(0); } while ((entry = fts_read(dirh)) != NULL) { switch (entry->fts_info) { case FTS_DNR: /* an error */ case FTS_ERR: case FTS_NS: msg("Can't fts_read %s: %s\n", entry->fts_path, strerror(errno)); /* FALLTHROUGH */ case FTS_DP: /* already seen dir */ continue; } mapfileino(entry->fts_statp->st_ino, tapesize, &anydirskipped); } if (errno) { msg("fts_read failed: %s\n", strerror(errno)); dumpabort(0); } (void)fts_close(dirh); /* * Add any parent directories */ for (d = 0 ; dirv[d] != NULL ; d++) { char path[PATH_MAX]; if (dirv[d][0] != '/') (void)snprintf(path, sizeof(path), "%s/%s", curdir, dirv[d]); else (void)snprintf(path, sizeof(path), "%s", dirv[d]); while (strcmp(path, disk) != 0) { char *p; struct stat sb; if (*path == '\0') break; if ((p = strrchr(path, '/')) == NULL) break; if (p == path) break; *p = '\0'; if (stat(path, &sb) == -1) { msg("Can't stat %s: %s\n", path, strerror(errno)); break; } mapfileino(sb.st_ino, tapesize, &anydirskipped); } } /* * Ensure that the root inode actually appears in the * file list for a subdir */ mapfileino(ROOTINO, tapesize, &anydirskipped); } else { fs_mapinodes(maxino, tapesize, &anydirskipped); } /* * Restore gets very upset if the root is not dumped, * so ensure that it always is dumped. */ SETINO(ROOTINO, dumpinomap); return (anydirskipped); } /* * Dump pass 2. * * Scan each directory on the filesystem to see if it has any modified * files in it. If it does, and has not already been added to the dump * list (because it was itself modified), then add it. If a directory * has not been modified itself, contains no modified files and has no * subdirectories, then it can be deleted from the dump list and from * the list of directories. By deleting it from the list of directories, * its parent may now qualify for the same treatment on this or a later * pass using this algorithm. */ int mapdirs(ino_t maxino, int64_t *tapesize) { union dinode *dp; int i, isdir, nodump; char *map; ino_t ino; union dinode di; off_t filesize; int ret, change = 0; isdir = 0; /* XXX just to get gcc to shut up */ for (map = dumpdirmap, ino = 1; ino < maxino; ino++) { if (((ino - 1) % NBBY) == 0) /* map is offset by 1 */ isdir = *map++; else isdir >>= 1; /* * If a directory has been removed from usedinomap, it * either has the nodump flag set, or has inherited * it. Although a directory can't be in dumpinomap if * it isn't in usedinomap, we have to go through it to * propagate the nodump flag. */ nodump = !nonodump && !TSTINO(ino, usedinomap); if ((isdir & 1) == 0 || (TSTINO(ino, dumpinomap) && !nodump)) continue; dp = getino(ino, &i); /* * inode buf may change in searchdir(). */ if (sblock->fs_magic == FS_UFS1_MAGIC) di.dp1 = dp->dp1; else di.dp2 = dp->dp2; filesize = (off_t)DIP(dp, di_size); for (ret = 0, i = 0; filesize > 0 && i < NDADDR; i++) { if (DIP(&di, di_db[i]) != 0) ret |= searchdir(ino, DIP(&di, di_db[i]), sblksize(sblock, DIP(dp, di_size), i), filesize, tapesize, nodump); if (ret & HASDUMPEDFILE) filesize = 0; else filesize -= sblock->fs_bsize; } for (i = 0; filesize > 0 && i < NIADDR; i++) { if (DIP(&di, di_ib[i]) == 0) continue; ret |= dirindir(ino, DIP(&di, di_ib[i]), i, &filesize, tapesize, nodump); } if (ret & HASDUMPEDFILE) { SETINO(ino, dumpinomap); *tapesize += blockest(dp); change = 1; continue; } if (nodump) { if (ret & HASSUBDIRS) change = 1; /* subdirs inherit nodump */ CLRINO(ino, dumpdirmap); } else if ((ret & HASSUBDIRS) == 0) { if (!TSTINO(ino, dumpinomap)) { CLRINO(ino, dumpdirmap); change = 1; } } } return (change); } /* * Read indirect blocks, and pass the data blocks to be searched * as directories. Quit as soon as any entry is found that will * require the directory to be dumped. */ static int dirindir(ino_t ino, daddr_t blkno, int ind_level, off_t *filesize, int64_t *tapesize, int nodump) { int ret = 0; int i; char idblk[MAXBSIZE]; bread(fsbtodb(sblock, blkno), idblk, (int)sblock->fs_bsize); if (ind_level <= 0) { for (i = 0; *filesize > 0 && i < NINDIR(sblock); i++) { if (sblock->fs_magic == FS_UFS1_MAGIC) blkno = ((int32_t *)idblk)[i]; else blkno = ((int64_t *)idblk)[i]; if (blkno != 0) ret |= searchdir(ino, blkno, sblock->fs_bsize, *filesize, tapesize, nodump); if (ret & HASDUMPEDFILE) *filesize = 0; else *filesize -= sblock->fs_bsize; } return (ret); } ind_level--; for (i = 0; *filesize > 0 && i < NINDIR(sblock); i++) { if (sblock->fs_magic == FS_UFS1_MAGIC) blkno = ((int32_t *)idblk)[i]; else blkno = ((int64_t *)idblk)[i]; if (blkno != 0) ret |= dirindir(ino, blkno, ind_level, filesize, tapesize, nodump); } return (ret); } /* * Scan a disk block containing directory information looking to see if * any of the entries are on the dump list and to see if the directory * contains any subdirectories. */ static int searchdir(ino_t ino, daddr_t blkno, long size, off_t filesize, int64_t *tapesize, int nodump) { struct direct *dp; union dinode *ip; long loc; static caddr_t dblk; int mode, ret = 0; if (dblk == NULL && (dblk = malloc(sblock->fs_bsize)) == NULL) quit("searchdir: cannot allocate indirect memory.\n"); bread(fsbtodb(sblock, blkno), dblk, (int)size); if (filesize < size) size = filesize; for (loc = 0; loc < size; ) { dp = (struct direct *)(dblk + loc); if (dp->d_reclen == 0) { msg("corrupted directory, inumber %llu\n", (unsigned long long)ino); break; } loc += dp->d_reclen; if (dp->d_ino == 0) continue; if (dp->d_name[0] == '.') { if (dp->d_name[1] == '\0') continue; if (dp->d_name[1] == '.' && dp->d_name[2] == '\0') continue; } if (nodump) { ip = getino(dp->d_ino, &mode); if (TSTINO(dp->d_ino, dumpinomap)) { CLRINO(dp->d_ino, dumpinomap); *tapesize -= blockest(ip); } /* * Add back to dumpdirmap and remove from usedinomap * to propagate nodump. */ if (mode == IFDIR) { SETINO(dp->d_ino, dumpdirmap); CLRINO(dp->d_ino, usedinomap); ret |= HASSUBDIRS; } } else { if (TSTINO(dp->d_ino, dumpinomap)) { ret |= HASDUMPEDFILE; if (ret & HASSUBDIRS) break; } if (TSTINO(dp->d_ino, dumpdirmap)) { ret |= HASSUBDIRS; if (ret & HASDUMPEDFILE) break; } } } return (ret); } /* * Dump passes 3 and 4. * * Dump the contents of an inode to tape. */ void dumpino(union dinode *dp, ino_t ino) { int ind_level, cnt; off_t size; char buf[TP_BSIZE]; if (newtape) { newtape = 0; dumpmap(dumpinomap, TS_BITS, ino); } CLRINO(ino, dumpinomap); if (sblock->fs_magic == FS_UFS1_MAGIC) { spcl.c_mode = dp->dp1.di_mode; spcl.c_size = dp->dp1.di_size; spcl.c_old_atime = (time_t)dp->dp1.di_atime; spcl.c_atime = dp->dp1.di_atime; spcl.c_atimensec = dp->dp1.di_atimensec; spcl.c_old_mtime = (time_t)dp->dp1.di_mtime; spcl.c_mtime = dp->dp1.di_mtime; spcl.c_mtimensec = dp->dp1.di_mtimensec; spcl.c_birthtime = 0; spcl.c_birthtimensec = 0; spcl.c_rdev = dp->dp1.di_rdev; spcl.c_file_flags = dp->dp1.di_flags; spcl.c_uid = dp->dp1.di_uid; spcl.c_gid = dp->dp1.di_gid; } else { spcl.c_mode = dp->dp2.di_mode; spcl.c_size = dp->dp2.di_size; spcl.c_atime = dp->dp2.di_atime; spcl.c_atimensec = dp->dp2.di_atimensec; spcl.c_mtime = dp->dp2.di_mtime; spcl.c_mtimensec = dp->dp2.di_mtimensec; spcl.c_birthtime = dp->dp2.di_birthtime; spcl.c_birthtimensec = dp->dp2.di_birthnsec; spcl.c_rdev = dp->dp2.di_rdev; spcl.c_file_flags = dp->dp2.di_flags; spcl.c_uid = dp->dp2.di_uid; spcl.c_gid = dp->dp2.di_gid; } spcl.c_type = TS_INODE; spcl.c_count = 0; switch (DIP(dp, di_mode) & S_IFMT) { case 0: /* * Freed inode. */ return; case IFLNK: /* * Check for short symbolic link. */ if (DIP(dp, di_size) > 0 && DIP(dp, di_size) < sblock->fs_maxsymlinklen) { void *shortlink; spcl.c_addr[0] = 1; spcl.c_count = 1; writeheader(ino); if (sblock->fs_magic == FS_UFS1_MAGIC) shortlink = dp->dp1.di_shortlink; else shortlink = dp->dp2.di_shortlink; memcpy(buf, shortlink, DIP(dp, di_size)); buf[DIP(dp, di_size)] = '\0'; writerec(buf, 0); return; } /* FALLTHROUGH */ case IFDIR: case IFREG: if (DIP(dp, di_size) > 0) break; /* FALLTHROUGH */ case IFIFO: case IFSOCK: case IFCHR: case IFBLK: writeheader(ino); return; default: msg("Warning: undefined file type 0%o\n", DIP(dp, di_mode) & IFMT); return; } if (DIP(dp, di_size) > NDADDR * sblock->fs_bsize) cnt = NDADDR * sblock->fs_frag; else cnt = howmany(DIP(dp, di_size), sblock->fs_fsize); if (sblock->fs_magic == FS_UFS1_MAGIC) ufs1_blksout(&dp->dp1.di_db[0], cnt, ino); else ufs2_blksout(&dp->dp2.di_db[0], cnt, ino); if ((size = DIP(dp, di_size) - NDADDR * sblock->fs_bsize) <= 0) return; for (ind_level = 0; ind_level < NIADDR; ind_level++) { dmpindir(ino, DIP(dp, di_ib[ind_level]), ind_level, &size); if (size <= 0) return; } } /* * Read indirect blocks, and pass the data blocks to be dumped. */ static void dmpindir(ino_t ino, daddr_t blk, int ind_level, off_t *size) { int i, cnt; char idblk[MAXBSIZE]; if (blk != 0) bread(fsbtodb(sblock, blk), idblk, (int) sblock->fs_bsize); else memset(idblk, 0, (int)sblock->fs_bsize); if (ind_level <= 0) { if (*size < NINDIR(sblock) * sblock->fs_bsize) cnt = howmany(*size, sblock->fs_fsize); else cnt = NINDIR(sblock) * sblock->fs_frag; *size -= NINDIR(sblock) * sblock->fs_bsize; if (sblock->fs_magic == FS_UFS1_MAGIC) ufs1_blksout((int32_t *)idblk, cnt, ino); else ufs2_blksout((int64_t *)idblk, cnt, ino); return; } ind_level--; for (i = 0; i < NINDIR(sblock); i++) { if (sblock->fs_magic == FS_UFS1_MAGIC) dmpindir(ino, ((int32_t *)idblk)[i], ind_level, size); else dmpindir(ino, ((int64_t *)idblk)[i], ind_level, size); if (*size <= 0) return; } } /* * Collect up the data into tape record sized buffers and output them. */ void ufs1_blksout(int32_t *blkp, int frags, ino_t ino) { int32_t *bp; int i, j, count, blks, tbperdb; blks = howmany(frags * sblock->fs_fsize, TP_BSIZE); tbperdb = sblock->fs_bsize >> tp_bshift; for (i = 0; i < blks; i += TP_NINDIR) { if (i + TP_NINDIR > blks) count = blks; else count = i + TP_NINDIR; for (j = i; j < count; j++) if (blkp[j / tbperdb] != 0) spcl.c_addr[j - i] = 1; else spcl.c_addr[j - i] = 0; spcl.c_count = count - i; writeheader(ino); bp = &blkp[i / tbperdb]; for (j = i; j < count; j += tbperdb, bp++) if (*bp != 0) { if (j + tbperdb <= count) dumpblock(*bp, (int)sblock->fs_bsize); else dumpblock(*bp, (count - j) * TP_BSIZE); } spcl.c_type = TS_ADDR; } } /* * Collect up the data into tape record sized buffers and output them. */ void ufs2_blksout(daddr_t *blkp, int frags, ino_t ino) { daddr_t *bp; int i, j, count, blks, tbperdb; blks = howmany(frags * sblock->fs_fsize, TP_BSIZE); tbperdb = sblock->fs_bsize >> tp_bshift; for (i = 0; i < blks; i += TP_NINDIR) { if (i + TP_NINDIR > blks) count = blks; else count = i + TP_NINDIR; for (j = i; j < count; j++) if (blkp[j / tbperdb] != 0) spcl.c_addr[j - i] = 1; else spcl.c_addr[j - i] = 0; spcl.c_count = count - i; writeheader(ino); bp = &blkp[i / tbperdb]; for (j = i; j < count; j += tbperdb, bp++) if (*bp != 0) { if (j + tbperdb <= count) dumpblock(*bp, (int)sblock->fs_bsize); else dumpblock(*bp, (count - j) * TP_BSIZE); } spcl.c_type = TS_ADDR; } } /* * Dump a map to the tape. */ void dumpmap(char *map, int type, ino_t ino) { int i; char *cp; spcl.c_type = type; spcl.c_count = howmany(mapsize * sizeof(char), TP_BSIZE); writeheader(ino); for (i = 0, cp = map; i < spcl.c_count; i++, cp += TP_BSIZE) writerec(cp, 0); } /* * Write a header record to the dump tape. */ void writeheader(ino_t ino) { int32_t sum, cnt, *lp; spcl.c_inumber = ino; if (sblock->fs_magic == FS_UFS2_MAGIC) { spcl.c_magic = FS_UFS2_MAGIC; } else { spcl.c_magic = NFS_MAGIC; spcl.c_old_date = (int32_t)spcl.c_date; spcl.c_old_ddate = (int32_t)spcl.c_ddate; spcl.c_old_tapea = (int32_t)spcl.c_tapea; spcl.c_old_firstrec = (int32_t)spcl.c_firstrec; } spcl.c_checksum = 0; lp = (int32_t *)&spcl; sum = 0; cnt = sizeof(union u_spcl) / (4 * sizeof(int32_t)); while (--cnt >= 0) { sum += *lp++; sum += *lp++; sum += *lp++; sum += *lp++; } spcl.c_checksum = CHECKSUM - sum; writerec((char *)&spcl, 1); } union dinode * getino(ino_t inum, int *modep) { static ino_t minino, maxino; static void *inoblock; struct ufs1_dinode *dp1; struct ufs2_dinode *dp2; if (inoblock == NULL && (inoblock = malloc(sblock->fs_bsize)) == NULL) quit("cannot allocate inode memory.\n"); curino = inum; if (inum >= minino && inum < maxino) goto gotit; bread(fsbtodb(sblock, ino_to_fsba(sblock, inum)), inoblock, (int)sblock->fs_bsize); minino = inum - (inum % INOPB(sblock)); maxino = minino + INOPB(sblock); gotit: if (sblock->fs_magic == FS_UFS1_MAGIC) { dp1 = &((struct ufs1_dinode *)inoblock)[inum - minino]; *modep = (dp1->di_mode & IFMT); return ((union dinode *)dp1); } dp2 = &((struct ufs2_dinode *)inoblock)[inum - minino]; *modep = (dp2->di_mode & IFMT); return ((union dinode *)dp2); } /* * Read a chunk of data from the disk. * Try to recover from hard errors by reading in sector sized pieces. * Error recovery is attempted at most BREADEMAX times before seeking * consent from the operator to continue. */ int breaderrors = 0; #define BREADEMAX 32 void bread(daddr_t blkno, char *buf, int size) { static char *mybuf = NULL; char *mybufp, *bufp, *np; static size_t mybufsz = 0; off_t offset; int cnt, i; u_int64_t secno, seccount; u_int32_t secoff, secsize = lab.d_secsize; /* * We must read an integral number of sectors large enough to contain * all the requested data. The read must begin at a sector. */ if (DL_BLKOFFSET(&lab, blkno) == 0 && size % secsize == 0) { secno = DL_BLKTOSEC(&lab, blkno); secoff = 0; seccount = size / secsize; bufp = buf; } else { secno = DL_BLKTOSEC(&lab, blkno); secoff = DL_BLKOFFSET(&lab, blkno); seccount = DL_BLKTOSEC(&lab, (size + secoff) / DEV_BSIZE); if (seccount * secsize < (size + secoff)) seccount++; if (mybufsz < seccount * secsize) { np = reallocarray(mybuf, seccount, secsize); if (np == NULL) { msg("No memory to read %llu %u-byte sectors", seccount, secsize); dumpabort(0); } mybufsz = seccount * secsize; mybuf = np; } bufp = mybuf; } offset = secno * secsize; loop: if ((cnt = pread(diskfd, bufp, seccount * secsize, offset)) == seccount * secsize) goto done; if (blkno + (size / DEV_BSIZE) > fsbtodb(sblock, sblock->fs_ffs1_size)) { /* * Trying to read the final fragment. * * NB - dump only works in TP_BSIZE blocks, hence * rounds `DEV_BSIZE' fragments up to TP_BSIZE pieces. * It should be smarter about not actually trying to * read more than it can get, but for the time being * we punt and scale back the read only when it gets * us into trouble. (mkm 9/25/83) */ size -= secsize; seccount--; goto loop; } if (cnt == -1) msg("read error from %s: %s: [block %lld]: count=%d\n", disk, strerror(errno), (long long)blkno, size); else msg("short read error from %s: [block %lld]: count=%d, " "got=%d\n", disk, (long long)blkno, size, cnt); if (++breaderrors > BREADEMAX) { msg("More than %d block read errors from %s\n", BREADEMAX, disk); broadcast("DUMP IS AILING!\n"); msg("This is an unrecoverable error.\n"); if (!query("Do you want to attempt to continue?")){ dumpabort(0); /*NOTREACHED*/ } else breaderrors = 0; } /* * Zero buffer, then try to read each sector of buffer separately. */ if (bufp == mybuf) memset(bufp, 0, mybufsz); else memset(bufp, 0, size); for (i = 0, mybufp = bufp; i < size; i += secsize, mybufp += secsize) { if ((cnt = pread(diskfd, mybufp, secsize, offset + i)) == secsize) continue; if (cnt == -1) { msg("read error from %s: %s: [block %lld]: " "count=%u\n", disk, strerror(errno), (long long)(offset + i) / DEV_BSIZE, secsize); continue; } msg("short read error from %s: [block %lld]: count=%u, " "got=%d\n", disk, (long long)(offset + i) / DEV_BSIZE, secsize, cnt); } done: /* If necessary, copy out data that was read. */ if (bufp == mybuf) memcpy(buf, bufp + secoff, size); }