diff options
Diffstat (limited to 'src/check.c')
-rw-r--r-- | src/check.c | 985 |
1 files changed, 985 insertions, 0 deletions
diff --git a/src/check.c b/src/check.c new file mode 100644 index 0000000..d6c54c1 --- /dev/null +++ b/src/check.c @@ -0,0 +1,985 @@ +/* check.c - Check and repair a PC/MS-DOS file system + + Copyright (C) 1993 Werner Almesberger <werner.almesberger@lrc.di.epfl.ch> + Copyright (C) 1998 Roman Hodek <Roman.Hodek@informatik.uni-erlangen.de> + + This program is free software: you can redistribute it and/or modify + it under the terms of the GNU General Public License as published by + the Free Software Foundation, either version 3 of the License, or + (at your option) any later version. + + This program is distributed in the hope that it will be useful, + but WITHOUT ANY WARRANTY; without even the implied warranty of + MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the + GNU General Public License for more details. + + You should have received a copy of the GNU General Public License + along with this program. If not, see <http://www.gnu.org/licenses/>. + + On Debian systems, the complete text of the GNU General Public License + can be found in /usr/share/common-licenses/GPL-3 file. +*/ + +/* FAT32, VFAT, Atari format support, and various fixes additions May 1998 + * by Roman Hodek <Roman.Hodek@informatik.uni-erlangen.de> */ + + +#include <stdio.h> +#include <stdlib.h> +#include <string.h> +#include <limits.h> +#include <time.h> + +#include "common.h" +#include "dosfsck.h" +#include "io.h" +#include "fat.h" +#include "file.h" +#include "lfn.h" +#include "check.h" + + +static DOS_FILE *root; + +/* get start field of a dir entry */ +#define FSTART(p,fs) \ + ((unsigned long)CF_LE_W(p->dir_ent.start) | \ + (fs->fat_bits == 32 ? CF_LE_W(p->dir_ent.starthi) << 16 : 0)) + +#define MODIFY(p,i,v) \ + do { \ + if (p->offset) { \ + p->dir_ent.i = v; \ + fs_write(p->offset+offsetof(DIR_ENT,i), \ + sizeof(p->dir_ent.i),&p->dir_ent.i); \ + } \ + } while(0) + +#define MODIFY_START(p,v,fs) \ + do { \ + unsigned long __v = (v); \ + if (!p->offset) { \ + /* writing to fake entry for FAT32 root dir */ \ + if (!__v) die("Oops, deleting FAT32 root dir!"); \ + fs->root_cluster = __v; \ + p->dir_ent.start = CT_LE_W(__v&0xffff); \ + p->dir_ent.starthi = CT_LE_W(__v>>16); \ + __v = CT_LE_L(__v); \ + fs_write((loff_t)offsetof(struct boot_sector,root_cluster), \ + sizeof(((struct boot_sector *)0)->root_cluster), \ + &__v); \ + } \ + else { \ + MODIFY(p,start,CT_LE_W((__v)&0xffff)); \ + if (fs->fat_bits == 32) \ + MODIFY(p,starthi,CT_LE_W((__v)>>16)); \ + } \ + } while(0) + + +loff_t alloc_rootdir_entry(DOS_FS *fs, DIR_ENT *de, const char *pattern) +{ + static int curr_num = 0; + loff_t offset; + + if (fs->root_cluster) { + DIR_ENT d2; + int i = 0, got = 0; + unsigned long clu_num, prev = 0; + loff_t offset2; + + clu_num = fs->root_cluster; + offset = cluster_start(fs,clu_num); + while (clu_num > 0 && clu_num != -1) { + fs_read(offset,sizeof(DIR_ENT),&d2); + if (IS_FREE(d2.name) && d2.attr != VFAT_LN_ATTR) { + got = 1; + break; + } + i += sizeof(DIR_ENT); + offset += sizeof(DIR_ENT); + if ((i % fs->cluster_size) == 0) { + prev = clu_num; + if ((clu_num = next_cluster(fs,clu_num)) == 0 || clu_num == -1) + break; + offset = cluster_start(fs,clu_num); + } + } + if (!got) { + /* no free slot, need to extend root dir: alloc next free cluster + * after previous one */ + if (!prev) + die("Root directory has no cluster allocated!"); + for (clu_num = prev+1; clu_num != prev; clu_num++) { + FAT_ENTRY entry; + + if (clu_num >= fs->clusters+2) clu_num = 2; + get_fat(&entry, fs->fat, clu_num, fs); + if (!entry.value) + break; + } + if (clu_num == prev) + die("Root directory full and no free cluster"); + set_fat(fs,prev,clu_num); + set_fat(fs,clu_num,-1); + set_owner(fs, clu_num, get_owner(fs, fs->root_cluster)); + /* clear new cluster */ + memset( &d2, 0, sizeof(d2) ); + offset = cluster_start(fs,clu_num); + for( i = 0; i < fs->cluster_size; i += sizeof(DIR_ENT) ) + fs_write( offset+i, sizeof(d2), &d2 ); + } + memset(de,0,sizeof(DIR_ENT)); + while (1) { + char expanded[12]; + sprintf(expanded, pattern, curr_num); + memcpy(de->name+4, expanded, 4); + memcpy(de->ext, expanded+4, 3); + clu_num = fs->root_cluster; + i = 0; + offset2 = cluster_start(fs,clu_num); + while (clu_num > 0 && clu_num != -1) { + fs_read(offset2,sizeof(DIR_ENT),&d2); + if (offset2 != offset && + !strncmp(d2.name,de->name,MSDOS_NAME)) + break; + i += sizeof(DIR_ENT); + offset2 += sizeof(DIR_ENT); + if ((i % fs->cluster_size) == 0) { + if ((clu_num = next_cluster(fs,clu_num)) == 0 || + clu_num == -1) + break; + offset2 = cluster_start(fs,clu_num); + } + } + if (clu_num == 0 || clu_num == -1) + break; + if (++curr_num >= 10000) die("Unable to create unique name"); + } + } + else { + DIR_ENT *root; + int next_free = 0, scan; + + root = alloc(fs->root_entries*sizeof(DIR_ENT)); + fs_read(fs->root_start,fs->root_entries*sizeof(DIR_ENT),root); + + while (next_free < fs->root_entries) + if (IS_FREE(root[next_free].name) && + root[next_free].attr != VFAT_LN_ATTR) + break; + else next_free++; + if (next_free == fs->root_entries) + die("Root directory is full."); + offset = fs->root_start+next_free*sizeof(DIR_ENT); + memset(de,0,sizeof(DIR_ENT)); + while (1) { + sprintf(de->name,pattern,curr_num); + for (scan = 0; scan < fs->root_entries; scan++) + if (scan != next_free && + !strncmp(root[scan].name,de->name,MSDOS_NAME)) + break; + if (scan == fs->root_entries) break; + if (++curr_num >= 10000) die("Unable to create unique name"); + } + free(root); + } + ++n_files; + return offset; +} + + +/** + * Construct a full path (starting with '/') for the specified dentry, + * relative to the partition. All components are "long" names where possible. + * + * @param[in] file Information about dentry (file or directory) of interest + * + * return Pointer to static string containing file's full path + */ +static char *path_name(DOS_FILE *file) +{ + static char path[PATH_MAX*2]; + + if (!file) *path = 0; /* Reached the root directory */ + else { + if (strlen(path_name(file->parent)) > PATH_MAX) + die("Path name too long."); + if (strcmp(path,"/") != 0) strcat(path,"/"); + + /* Append the long name to the path, + * or the short name if there isn't a long one + */ + strcpy(strrchr(path,0),file->lfn?file->lfn:file_name(file->dir_ent.name)); + } + return path; +} + + +static int day_n[] = { 0,31,59,90,120,151,181,212,243,273,304,334,0,0,0,0 }; + /* JanFebMarApr May Jun Jul Aug Sep Oct Nov Dec */ + + +/* Convert a MS-DOS time/date pair to a UNIX date (seconds since 1 1 70). */ + +time_t date_dos2unix(unsigned short time,unsigned short date) +{ + int month,year; + time_t secs; + + month = ((date >> 5) & 15)-1; + year = date >> 9; + secs = (time & 31)*2+60*((time >> 5) & 63)+(time >> 11)*3600+86400* + ((date & 31)-1+day_n[month]+(year/4)+year*365-((year & 3) == 0 && + month < 2 ? 1 : 0)+3653); + /* days since 1.1.70 plus 80's leap day */ + return secs; +} + + +static char *file_stat(DOS_FILE *file) +{ + static char temp[100]; + struct tm *tm; + char tmp[100]; + time_t date; + + date = date_dos2unix(CF_LE_W(file->dir_ent.time),CF_LE_W(file-> + dir_ent.date)); + tm = localtime(&date); + strftime(tmp,99,"%H:%M:%S %b %d %Y",tm); + sprintf(temp," Size %u bytes, date %s",CF_LE_L(file->dir_ent.size),tmp); + return temp; +} + + +static int bad_name(DOS_FILE *file) +{ + int i, spc, suspicious = 0; + char *bad_chars = atari_format ? "*?\\/:" : "*?<>|\"\\/:"; + unsigned char *name = file->dir_ent.name; + + /* Do not complain about (and auto-correct) the extended attribute files + * of OS/2. */ + if (strncmp(name,"EA DATA SF",11) == 0 || + strncmp(name,"WP ROOT SF",11) == 0) return 0; + + /* don't complain about the dummy 11 bytes used by patched Linux + kernels */ + if (file->dir_ent.lcase & FAT_NO_83NAME) return 0; + + for (i = 0; i < 8; i++) { + if (name[i] < ' ' || name[i] == 0x7f) return 1; + if (name[i] > 0x7f) ++suspicious; + if (strchr(bad_chars,name[i])) return 1; + } + + for (i = 8; i < 11; i++) { + if (name[i] < ' ' || name[i] == 0x7f) return 1; + if (name[i] > 0x7f) ++suspicious; + if (strchr(bad_chars,name[i])) return 1; + } + + spc = 0; + for (i = 0; i < 8; i++) { + if (name[i] == ' ') + spc = 1; + else if (spc) + /* non-space after a space not allowed, space terminates the name + * part */ + return 1; + } + + spc = 0; + for (i = 8; i < 11; i++) { + if (name[i] == ' ') + spc = 1; + else if (spc) + /* non-space after a space not allowed, space terminates the name + * part */ + return 1; + } + + /* Under GEMDOS, chars >= 128 are never allowed. */ + if (atari_format && suspicious) + return 1; + + /* Under MS-DOS and Windows, chars >= 128 in short names are valid + * (but these characters can be visualised differently depending on + * local codepage: CP437, CP866, etc). The chars are all basically ok, + * so we shouldn't auto-correct such names. */ + return 0; +} + +static void lfn_remove(loff_t from, loff_t to) +{ + int i; + DIR_ENT empty; + + /* New dir entry is zeroed except first byte, which is set to 0xe5. + * This is to avoid that some FAT-reading OSes (not Linux! ;) stop reading + * a directory at the first zero entry... + */ + memset( &empty, 0, sizeof(empty) ); + empty.name[0] = DELETED_FLAG; + + for( ; from < to; from += sizeof(empty) ) { + fs_write( from, sizeof(DIR_ENT), &empty ); + } +} + +static void drop_file(DOS_FS *fs,DOS_FILE *file) +{ + unsigned long cluster; + + MODIFY(file,name[0],DELETED_FLAG); + if (file->lfn) lfn_remove(file->lfn_offset, file->offset); + for (cluster = FSTART(file,fs); cluster > 0 && cluster < + fs->clusters+2; cluster = next_cluster(fs,cluster)) + set_owner(fs,cluster,NULL); + --n_files; +} + + +static void truncate_file(DOS_FS *fs,DOS_FILE *file,unsigned long clusters) +{ + int deleting; + unsigned long walk,next,prev; + + walk = FSTART(file,fs); + prev = 0; + if ((deleting = !clusters)) MODIFY_START(file,0,fs); + while (walk > 0 && walk != -1) { + next = next_cluster(fs,walk); + if (deleting) set_fat(fs,walk,0); + else if ((deleting = !--clusters)) set_fat(fs,walk,-1); + prev = walk; + walk = next; + } +} + + +static void auto_rename(DOS_FILE *file) +{ + DOS_FILE *first,*walk; + unsigned long int number; + + if (!file->offset) return; /* cannot rename FAT32 root dir */ + first = file->parent ? file->parent->first : root; + number = 0; + while (1) { + char num[8]; + sprintf(num, "%07d", number); + memcpy(file->dir_ent.name, "FSCK", 4); + memcpy(file->dir_ent.name+4, num, 4); + memcpy(file->dir_ent.ext, num+4, 3); + for (walk = first; walk; walk = walk->next) + if (walk != file && !strncmp(walk->dir_ent.name,file->dir_ent. + name,MSDOS_NAME)) break; + if (!walk) { + fs_write(file->offset,MSDOS_NAME,file->dir_ent.name); + if (file->lfn) lfn_fix_checksum(file->lfn_offset, file->offset, file->dir_ent.name); + return; + } + number++; + if (number > 9999999) { + die("Too many files need repair."); + } + } + die("Can't generate a unique name."); +} + + +static void rename_file(DOS_FILE *file) +{ + unsigned char name[46]; + unsigned char *walk,*here; + + if (!file->offset) { + printf( "Cannot rename FAT32 root dir\n" ); + return; /* cannot rename FAT32 root dir */ + } + while (1) { + printf("New name: "); + fflush(stdout); + if (fgets(name,45,stdin)) { + if ((here = strchr(name,'\n'))) *here = 0; + for (walk = strrchr(name,0); walk >= name && (*walk == ' ' || + *walk == '\t'); walk--); + walk[1] = 0; + for (walk = name; *walk == ' ' || *walk == '\t'; walk++); + if (file_cvt(walk,file->dir_ent.name)) { + fs_write(file->offset,MSDOS_NAME,file->dir_ent.name); + if (file->lfn) lfn_fix_checksum(file->lfn_offset, file->offset, file->dir_ent.name); + return; + } + } + } +} + + +static int handle_dot(DOS_FS *fs,DOS_FILE *file,int dots) +{ + char *name; + + name = strncmp(file->dir_ent.name,MSDOS_DOT,MSDOS_NAME) ? ".." : "."; + if (!(file->dir_ent.attr & ATTR_DIR)) { + printf("%s\n Is a non-directory.\n",path_name(file)); + if (interactive) + printf("1) Drop it\n2) Auto-rename\n3) Rename\n" + "4) Convert to directory\n"); + else printf(" Auto-renaming it.\n"); + switch (interactive ? get_key("1234","?") : '2') { + case '1': + drop_file(fs,file); + return 1; + case '2': + auto_rename(file); + printf(" Renamed to %s\n",file_name(file->dir_ent.name)); + return 0; + case '3': + rename_file(file); + return 0; + case '4': + MODIFY(file,size,CT_LE_L(0)); + MODIFY(file,attr,file->dir_ent.attr | ATTR_DIR); + break; + } + } + if (!dots) { + printf("Root contains directory \"%s\". Dropping it.\n",name); + drop_file(fs,file); + return 1; + } + return 0; +} + + +static int check_file(DOS_FS *fs,DOS_FILE *file) +{ + DOS_FILE *owner; + int restart; + unsigned long expect,curr,this,clusters,prev,walk,clusters2; + + if (file->dir_ent.attr & ATTR_DIR) { + if (CF_LE_L(file->dir_ent.size)) { + printf("%s\n Directory has non-zero size. Fixing it.\n", + path_name(file)); + MODIFY(file,size,CT_LE_L(0)); + } + if (file->parent && !strncmp(file->dir_ent.name,MSDOS_DOT,MSDOS_NAME)) { + expect = FSTART(file->parent,fs); + if (FSTART(file,fs) != expect) { + printf("%s\n Start (%ld) does not point to parent (%ld)\n", + path_name(file),FSTART(file,fs),expect); + MODIFY_START(file,expect,fs); + } + return 0; + } + if (file->parent && !strncmp(file->dir_ent.name,MSDOS_DOTDOT, + MSDOS_NAME)) { + expect = file->parent->parent ? FSTART(file->parent->parent,fs):0; + if (fs->root_cluster && expect == fs->root_cluster) + expect = 0; + if (FSTART(file,fs) != expect) { + printf("%s\n Start (%lu) does not point to .. (%lu)\n", + path_name(file),FSTART(file,fs),expect); + MODIFY_START(file,expect,fs); + } + return 0; + } + if (FSTART(file,fs)==0){ + printf ("%s\n Start does point to root directory. Deleting dir. \n", + path_name(file)); + MODIFY(file,name[0],DELETED_FLAG); + return 0; + } + } + if (FSTART(file,fs) >= fs->clusters+2) { + printf("%s\n Start cluster beyond limit (%lu > %lu). Truncating file.\n", + path_name(file),FSTART(file,fs),fs->clusters+1); + if (!file->offset) + die( "Bad FAT32 root directory! (bad start cluster)\n" ); + MODIFY_START(file,0,fs); + } + clusters = prev = 0; + for (curr = FSTART(file,fs) ? FSTART(file,fs) : + -1; curr != -1; curr = next_cluster(fs,curr)) { + FAT_ENTRY curEntry; + get_fat(&curEntry, fs->fat, curr, fs); + + if (!curEntry.value || bad_cluster(fs,curr)) { + printf("%s\n Contains a %s cluster (%lu). Assuming EOF.\n", + path_name(file), curEntry.value ? "bad" : "free",curr); + if (prev) set_fat(fs,prev,-1); + else if (!file->offset) + die( "FAT32 root dir starts with a bad cluster!" ); + else MODIFY_START(file,0,fs); + break; + } + if (!(file->dir_ent.attr & ATTR_DIR) && CF_LE_L(file->dir_ent.size) <= + (unsigned long long)clusters*fs->cluster_size) { + printf("%s\n File size is %u bytes, cluster chain length is > %llu " + "bytes.\n Truncating file to %u bytes.\n",path_name(file), + CF_LE_L(file->dir_ent.size),(unsigned long long)clusters*fs->cluster_size, + CF_LE_L(file->dir_ent.size)); + truncate_file(fs,file,clusters); + break; + } + if ((owner = get_owner(fs,curr))) { + int do_trunc = 0; + printf("%s and\n",path_name(owner)); + printf("%s\n share clusters.\n",path_name(file)); + clusters2 = 0; + for (walk = FSTART(owner,fs); walk > 0 && walk != -1; walk = + next_cluster(fs,walk)) + if (walk == curr) break; + else clusters2++; + restart = file->dir_ent.attr & ATTR_DIR; + if (!owner->offset) { + printf( " Truncating second to %llu bytes because first " + "is FAT32 root dir.\n", (unsigned long long)clusters2*fs->cluster_size ); + do_trunc = 2; + } + else if (!file->offset) { + printf( " Truncating first to %llu bytes because second " + "is FAT32 root dir.\n", (unsigned long long)clusters*fs->cluster_size ); + do_trunc = 1; + } + else if (interactive) + printf("1) Truncate first to %llu bytes%s\n" + "2) Truncate second to %llu bytes\n",(unsigned long long)clusters*fs->cluster_size, + restart ? " and restart" : "",(unsigned long long)clusters2*fs->cluster_size); + else printf(" Truncating second to %llu bytes.\n",(unsigned long long)clusters2* + fs->cluster_size); + if (do_trunc != 2 && + (do_trunc == 1 || + (interactive && get_key("12","?") == '1'))) { + prev = 0; + clusters = 0; + for (this = FSTART(owner,fs); this > 0 && this != -1; this = + next_cluster(fs,this)) { + if (this == curr) { + if (prev) set_fat(fs,prev,-1); + else MODIFY_START(owner,0,fs); + MODIFY(owner,size,CT_LE_L((unsigned long long)clusters*fs->cluster_size)); + if (restart) return 1; + while (this > 0 && this != -1) { + set_owner(fs,this,NULL); + this = next_cluster(fs,this); + } + this = curr; + break; + } + clusters++; + prev = this; + } + if (this != curr) + die("Internal error: didn't find cluster %d in chain" + " starting at %d",curr,FSTART(owner,fs)); + } + else { + if (prev) set_fat(fs,prev,-1); + else MODIFY_START(file,0,fs); + break; + } + } + set_owner(fs,curr,file); + clusters++; + prev = curr; + } + if (!(file->dir_ent.attr & ATTR_DIR) && CF_LE_L(file->dir_ent.size) > + (unsigned long long)clusters*fs->cluster_size) { + printf("%s\n File size is %u bytes, cluster chain length is %llu bytes." + "\n Truncating file to %lu bytes.\n",path_name(file),CF_LE_L(file-> + dir_ent.size),(unsigned long long)clusters*fs->cluster_size,(unsigned long long)clusters*fs->cluster_size); + MODIFY(file,size,CT_LE_L((unsigned long long)clusters*fs->cluster_size)); + } + return 0; +} + + +static int check_files(DOS_FS *fs,DOS_FILE *start) +{ + while (start) { + if (check_file(fs,start)) return 1; + start = start->next; + } + return 0; +} + + +static int check_dir(DOS_FS *fs,DOS_FILE **root,int dots) +{ + DOS_FILE *parent,**walk,**scan; + int dot,dotdot,skip,redo; + int good,bad; + + if (!*root) return 0; + parent = (*root)->parent; + good = bad = 0; + for (walk = root; *walk; walk = &(*walk)->next) + if (bad_name(*walk)) bad++; + else good++; + if (*root && parent && good+bad > 4 && bad > good/2) { + printf("%s\n Has a large number of bad entries. (%d/%d)\n", + path_name(parent),bad,good+bad); + if (!dots) printf( " Not dropping root directory.\n" ); + else if (!interactive) printf(" Not dropping it in auto-mode.\n"); + else if (get_key("yn","Drop directory ? (y/n)") == 'y') { + truncate_file(fs,parent,0); + MODIFY(parent,name[0],DELETED_FLAG); + /* buglet: deleted directory stays in the list. */ + return 1; + } + } + dot = dotdot = redo = 0; + walk = root; + while (*walk) { + if (!strncmp((*walk)->dir_ent.name,MSDOS_DOT,MSDOS_NAME) || + !strncmp((*walk)->dir_ent.name,MSDOS_DOTDOT,MSDOS_NAME)) { + if (handle_dot(fs,*walk,dots)) { + *walk = (*walk)->next; + continue; + } + if (!strncmp((*walk)->dir_ent.name,MSDOS_DOT,MSDOS_NAME)) dot++; + else dotdot++; + } + if (!((*walk)->dir_ent.attr & ATTR_VOLUME) && + bad_name(*walk)) { + puts(path_name(*walk)); + printf(" Bad short file name (%s).\n", file_name((*walk)->dir_ent.name)); + if (interactive) + printf("1) Drop file\n2) Rename file\n3) Auto-rename\n" + "4) Keep it\n"); + else printf(" Auto-renaming it.\n"); + switch (interactive ? get_key("1234","?") : '3') { + case '1': + drop_file(fs,*walk); + walk = &(*walk)->next; + continue; + case '2': + rename_file(*walk); + redo = 1; + break; + case '3': + auto_rename(*walk); + printf(" Renamed to %s\n",file_name((*walk)->dir_ent. + name)); + break; + case '4': + break; + } + } + /* don't check for duplicates of the volume label */ + if (!((*walk)->dir_ent.attr & ATTR_VOLUME)) { + scan = &(*walk)->next; + skip = 0; + while (*scan && !skip) { + if (!((*scan)->dir_ent.attr & ATTR_VOLUME) && + !memcmp((*walk)->dir_ent.name,(*scan)->dir_ent.name,MSDOS_NAME)) { + printf("%s\n Duplicate directory entry.\n First %s\n", + path_name(*walk),file_stat(*walk)); + printf(" Second %s\n",file_stat(*scan)); + if (interactive) + printf("1) Drop first\n2) Drop second\n3) Rename first\n" + "4) Rename second\n5) Auto-rename first\n" + "6) Auto-rename second\n"); + else printf(" Auto-renaming second.\n"); + switch (interactive ? get_key("123456","?") : '6') { + case '1': + drop_file(fs,*walk); + *walk = (*walk)->next; + skip = 1; + break; + case '2': + drop_file(fs,*scan); + *scan = (*scan)->next; + continue; + case '3': + rename_file(*walk); + printf(" Renamed to %s\n",path_name(*walk)); + redo = 1; + break; + case '4': + rename_file(*scan); + printf(" Renamed to %s\n",path_name(*walk)); + redo = 1; + break; + case '5': + auto_rename(*walk); + printf(" Renamed to %s\n",file_name((*walk)->dir_ent. + name)); + break; + case '6': + auto_rename(*scan); + printf(" Renamed to %s\n",file_name((*scan)->dir_ent. + name)); + break; + } + } + scan = &(*scan)->next; + } + if (skip) continue; + } + if (!redo) walk = &(*walk)->next; + else { + walk = root; + dot = dotdot = redo = 0; + } + } + if (dots && !dot) + printf("%s\n \".\" is missing. Can't fix this yet.\n", + path_name(parent)); + if (dots && !dotdot) + printf("%s\n \"..\" is missing. Can't fix this yet.\n", + path_name(parent)); + return 0; +} + + +/** + * Check a dentry's cluster chain for bad clusters. + * If requested, we verify readability and mark unreadable clusters as bad. + * + * @param[inout] fs Information about the filesystem + * @param[in] file dentry to check + * @param[in] read_test Nonzero == verify that dentry's clusters can + * be read + */ +static void test_file(DOS_FS *fs,DOS_FILE *file,int read_test) +{ + DOS_FILE *owner; + unsigned long walk,prev,clusters,next_clu; + + prev = clusters = 0; + for (walk = FSTART(file,fs); walk > 0 && walk < fs->clusters+2; + walk = next_clu) { + next_clu = next_cluster(fs,walk); + + /* In this stage we are checking only for a loop within our own + * cluster chain. + * Cross-linking of clusters is handled in check_file() + */ + if ((owner = get_owner(fs,walk))) { + if (owner == file) { + printf("%s\n Circular cluster chain. Truncating to %lu " + "cluster%s.\n",path_name(file),clusters,clusters == 1 ? "" : + "s"); + if (prev) set_fat(fs,prev,-1); + else if (!file->offset) + die( "Bad FAT32 root directory! (bad start cluster)\n" ); + else MODIFY_START(file,0,fs); + } + break; + } + if (bad_cluster(fs,walk)) break; + if (read_test) { + if (fs_test(cluster_start(fs,walk),fs->cluster_size)) { + prev = walk; + clusters++; + } + else { + printf("%s\n Cluster %lu (%lu) is unreadable. Skipping it.\n", + path_name(file),clusters,walk); + if (prev) set_fat(fs,prev,next_cluster(fs,walk)); + else MODIFY_START(file,next_cluster(fs,walk),fs); + set_fat(fs,walk,-2); + } + } + set_owner(fs,walk,file); + } + /* Revert ownership (for now) */ + for (walk = FSTART(file,fs); walk > 0 && walk < fs->clusters+2; + walk = next_cluster(fs,walk)) + if (bad_cluster(fs,walk)) break; + else if (get_owner(fs,walk) == file) set_owner(fs,walk,NULL); + else break; +} + + +static void undelete(DOS_FS *fs,DOS_FILE *file) +{ + unsigned long clusters,left,prev,walk; + + clusters = left = (CF_LE_L(file->dir_ent.size)+fs->cluster_size-1)/ + fs->cluster_size; + prev = 0; + + walk = FSTART(file,fs); + + while (left && (walk >= 2) && (walk < fs->clusters+2)) { + + FAT_ENTRY curEntry; + get_fat(&curEntry, fs->fat, walk, fs); + + if (!curEntry.value) + break; + + left--; + if (prev) set_fat(fs,prev,walk); + prev = walk; + walk++; + } + if (prev) set_fat(fs,prev,-1); + else MODIFY_START(file,0,fs); + if (left) + printf("Warning: Did only undelete %lu of %lu cluster%s.\n",clusters-left, + clusters,clusters == 1 ? "" : "s"); + +} + + +static void new_dir( void ) +{ + lfn_reset(); +} + + +/** + * Create a description for a referenced dentry and insert it in our dentry + * tree. Then, go check the dentry's cluster chain for bad clusters and + * cluster loops. + * + * @param[inout] fs Information about the filesystem + * @param[out] chain + * @param[in] parent Information about parent directory of this file + * NULL == no parent ('file' is root directory) + * @param[in] offset Partition-relative byte offset of directory entry of interest + * 0 == Root directory + * @param cp + */ +static void add_file(DOS_FS *fs,DOS_FILE ***chain,DOS_FILE *parent, + loff_t offset,FDSC **cp) +{ + DOS_FILE *new; + DIR_ENT de; + FD_TYPE type; + + if (offset) + fs_read(offset,sizeof(DIR_ENT),&de); + else { + /* Construct a DIR_ENT for the root directory */ + memcpy(de.name," ",MSDOS_NAME); + de.attr = ATTR_DIR; + de.size = de.time = de.date = 0; + de.start = CT_LE_W(fs->root_cluster & 0xffff); + de.starthi = CT_LE_W((fs->root_cluster >> 16) & 0xffff); + } + if ((type = file_type(cp,de.name)) != fdt_none) { + if (type == fdt_undelete && (de.attr & ATTR_DIR)) + die("Can't undelete directories."); + file_modify(cp,de.name); + fs_write(offset,1,&de); + } + if (IS_FREE(de.name)) { + lfn_check_orphaned(); + return; + } + if (de.attr == VFAT_LN_ATTR) { + lfn_add_slot(&de,offset); + return; + } + new = qalloc(&mem_queue,sizeof(DOS_FILE)); + new->lfn = lfn_get(&de, &new->lfn_offset); + new->offset = offset; + memcpy(&new->dir_ent,&de,sizeof(de)); + new->next = new->first = NULL; + new->parent = parent; + if (type == fdt_undelete) undelete(fs,new); + **chain = new; + *chain = &new->next; + if (list) { + printf("Checking file %s",path_name(new)); + if (new->lfn) + printf(" (%s)", file_name(new->dir_ent.name) ); /* (8.3) */ + printf("\n"); + } + /* Don't include root directory, '.', or '..' in the total file count */ + if (offset && + strncmp(de.name,MSDOS_DOT,MSDOS_NAME) != 0 && + strncmp(de.name,MSDOS_DOTDOT,MSDOS_NAME) != 0) + ++n_files; + test_file(fs,new,test); /* Bad cluster check */ +} + + +static int subdirs(DOS_FS *fs,DOS_FILE *parent,FDSC **cp); + + +static int scan_dir(DOS_FS *fs,DOS_FILE *this,FDSC **cp) +{ + DOS_FILE **chain; + int i; + unsigned long clu_num; + + chain = &this->first; + i = 0; + clu_num = FSTART(this,fs); + new_dir(); + while (clu_num > 0 && clu_num != -1) { + add_file(fs,&chain,this,cluster_start(fs,clu_num)+(i % fs-> + cluster_size),cp); + i += sizeof(DIR_ENT); + if (!(i % fs->cluster_size)) + if ((clu_num = next_cluster(fs,clu_num)) == 0 || clu_num == -1) + break; + } + lfn_check_orphaned(); + if (check_dir(fs,&this->first,this->offset)) return 0; + if (check_files(fs,this->first)) return 1; + return subdirs(fs,this,cp); +} + + +/** + * Recursively scan subdirectories of the specified parent directory. + * + * @param[inout] fs Information about the filesystem + * @param[in] parent Identifies the directory to scan + * @param[in] cp + * + * @return 0 Success + * @return 1 Error + */ +static int subdirs(DOS_FS *fs,DOS_FILE *parent,FDSC **cp) +{ + DOS_FILE *walk; + + for (walk = parent ? parent->first : root; walk; walk = walk->next) + if (walk->dir_ent.attr & ATTR_DIR) + if (strncmp(walk->dir_ent.name,MSDOS_DOT,MSDOS_NAME) && + strncmp(walk->dir_ent.name,MSDOS_DOTDOT,MSDOS_NAME)) + if (scan_dir(fs,walk,file_cd(cp,walk->dir_ent.name))) return 1; + return 0; +} + + +/** + * Scan all directory and file information for errors. + * + * @param[inout] fs Information about the filesystem + * + * @return 0 Success + * @return 1 Error + */ +int scan_root(DOS_FS *fs) +{ + DOS_FILE **chain; + int i; + + root = NULL; + chain = &root; + new_dir(); + if (fs->root_cluster) { + add_file(fs,&chain,NULL,0,&fp_root); + } + else { + for (i = 0; i < fs->root_entries; i++) + add_file(fs,&chain,NULL,fs->root_start+i*sizeof(DIR_ENT),&fp_root); + } + lfn_check_orphaned(); + (void) check_dir(fs,&root,0); + if (check_files(fs,root)) return 1; + return subdirs(fs,NULL,&fp_root); +} |