| Current Path : /usr/src/sbin/restore/ |
FreeBSD hs32.drive.ne.jp 9.1-RELEASE FreeBSD 9.1-RELEASE #1: Wed Jan 14 12:18:08 JST 2015 root@hs32.drive.ne.jp:/sys/amd64/compile/hs32 amd64 |
| Current File : //usr/src/sbin/restore/symtab.c |
/*
* Copyright (c) 1983, 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.
* 4. 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.
*/
#ifndef lint
#if 0
static char sccsid[] = "@(#)symtab.c 8.3 (Berkeley) 4/28/95";
#endif
static const char rcsid[] =
"$FreeBSD: release/9.1.0/sbin/restore/symtab.c 207998 2010-05-12 20:21:44Z brueffer $";
#endif /* not lint */
/*
* These routines maintain the symbol table which tracks the state
* of the file system being restored. They provide lookup by either
* name or inode number. They also provide for creation, deletion,
* and renaming of entries. Because of the dynamic nature of pathnames,
* names should not be saved, but always constructed just before they
* are needed, by calling "myname".
*/
#include <sys/param.h>
#include <sys/stat.h>
#include <ufs/ufs/dinode.h>
#include <errno.h>
#include <fcntl.h>
#include <limits.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <unistd.h>
#include "restore.h"
#include "extern.h"
/*
* The following variables define the inode symbol table.
* The primary hash table is dynamically allocated based on
* the number of inodes in the file system (maxino), scaled by
* HASHFACTOR. The variable "entry" points to the hash table;
* the variable "entrytblsize" indicates its size (in entries).
*/
#define HASHFACTOR 5
static struct entry **entry;
static long entrytblsize;
static void addino(ino_t, struct entry *);
static struct entry *lookupparent(char *);
static void removeentry(struct entry *);
/*
* Look up an entry by inode number
*/
struct entry *
lookupino(ino_t inum)
{
struct entry *ep;
if (inum < WINO || inum >= maxino)
return (NULL);
for (ep = entry[inum % entrytblsize]; ep != NULL; ep = ep->e_next)
if (ep->e_ino == inum)
return (ep);
return (NULL);
}
/*
* Add an entry into the entry table
*/
static void
addino(ino_t inum, struct entry *np)
{
struct entry **epp;
if (inum < WINO || inum >= maxino)
panic("addino: out of range %d\n", inum);
epp = &entry[inum % entrytblsize];
np->e_ino = inum;
np->e_next = *epp;
*epp = np;
if (dflag)
for (np = np->e_next; np != NULL; np = np->e_next)
if (np->e_ino == inum)
badentry(np, "duplicate inum");
}
/*
* Delete an entry from the entry table
*/
void
deleteino(ino_t inum)
{
struct entry *next;
struct entry **prev;
if (inum < WINO || inum >= maxino)
panic("deleteino: out of range %d\n", inum);
prev = &entry[inum % entrytblsize];
for (next = *prev; next != NULL; next = next->e_next) {
if (next->e_ino == inum) {
next->e_ino = 0;
*prev = next->e_next;
return;
}
prev = &next->e_next;
}
panic("deleteino: %d not found\n", inum);
}
/*
* Look up an entry by name
*/
struct entry *
lookupname(char *name)
{
struct entry *ep;
char *np, *cp;
char buf[MAXPATHLEN];
cp = name;
for (ep = lookupino(ROOTINO); ep != NULL; ep = ep->e_entries) {
for (np = buf; *cp != '/' && *cp != '\0' &&
np < &buf[sizeof(buf)]; )
*np++ = *cp++;
if (np == &buf[sizeof(buf)])
break;
*np = '\0';
for ( ; ep != NULL; ep = ep->e_sibling)
if (strcmp(ep->e_name, buf) == 0)
break;
if (ep == NULL)
break;
if (*cp++ == '\0')
return (ep);
}
return (NULL);
}
/*
* Look up the parent of a pathname
*/
static struct entry *
lookupparent(char *name)
{
struct entry *ep;
char *tailindex;
tailindex = strrchr(name, '/');
if (tailindex == NULL)
return (NULL);
*tailindex = '\0';
ep = lookupname(name);
*tailindex = '/';
if (ep == NULL)
return (NULL);
if (ep->e_type != NODE)
panic("%s is not a directory\n", name);
return (ep);
}
/*
* Determine the current pathname of a node or leaf
*/
char *
myname(struct entry *ep)
{
char *cp;
static char namebuf[MAXPATHLEN];
for (cp = &namebuf[MAXPATHLEN - 2]; cp > &namebuf[ep->e_namlen]; ) {
cp -= ep->e_namlen;
memmove(cp, ep->e_name, (long)ep->e_namlen);
if (ep == lookupino(ROOTINO))
return (cp);
*(--cp) = '/';
ep = ep->e_parent;
}
panic("%s: pathname too long\n", cp);
return(cp);
}
/*
* Unused symbol table entries are linked together on a free list
* headed by the following pointer.
*/
static struct entry *freelist = NULL;
/*
* add an entry to the symbol table
*/
struct entry *
addentry(char *name, ino_t inum, int type)
{
struct entry *np, *ep;
if (freelist != NULL) {
np = freelist;
freelist = np->e_next;
memset(np, 0, (long)sizeof(struct entry));
} else {
np = (struct entry *)calloc(1, sizeof(struct entry));
if (np == NULL)
panic("no memory to extend symbol table\n");
}
np->e_type = type & ~LINK;
ep = lookupparent(name);
if (ep == NULL) {
if (inum != ROOTINO || lookupino(ROOTINO) != NULL)
panic("bad name to addentry %s\n", name);
np->e_name = savename(name);
np->e_namlen = strlen(name);
np->e_parent = np;
addino(ROOTINO, np);
return (np);
}
np->e_name = savename(strrchr(name, '/') + 1);
np->e_namlen = strlen(np->e_name);
np->e_parent = ep;
np->e_sibling = ep->e_entries;
ep->e_entries = np;
if (type & LINK) {
ep = lookupino(inum);
if (ep == NULL)
panic("link to non-existent name\n");
np->e_ino = inum;
np->e_links = ep->e_links;
ep->e_links = np;
} else if (inum != 0) {
if (lookupino(inum) != NULL)
panic("duplicate entry\n");
addino(inum, np);
}
return (np);
}
/*
* delete an entry from the symbol table
*/
void
freeentry(struct entry *ep)
{
struct entry *np;
ino_t inum;
if (ep->e_flags != REMOVED)
badentry(ep, "not marked REMOVED");
if (ep->e_type == NODE) {
if (ep->e_links != NULL)
badentry(ep, "freeing referenced directory");
if (ep->e_entries != NULL)
badentry(ep, "freeing non-empty directory");
}
if (ep->e_ino != 0) {
np = lookupino(ep->e_ino);
if (np == NULL)
badentry(ep, "lookupino failed");
if (np == ep) {
inum = ep->e_ino;
deleteino(inum);
if (ep->e_links != NULL)
addino(inum, ep->e_links);
} else {
for (; np != NULL; np = np->e_links) {
if (np->e_links == ep) {
np->e_links = ep->e_links;
break;
}
}
if (np == NULL)
badentry(ep, "link not found");
}
}
removeentry(ep);
freename(ep->e_name);
ep->e_next = freelist;
freelist = ep;
}
/*
* Relocate an entry in the tree structure
*/
void
moveentry(struct entry *ep, char *newname)
{
struct entry *np;
char *cp;
np = lookupparent(newname);
if (np == NULL)
badentry(ep, "cannot move ROOT");
if (np != ep->e_parent) {
removeentry(ep);
ep->e_parent = np;
ep->e_sibling = np->e_entries;
np->e_entries = ep;
}
cp = strrchr(newname, '/') + 1;
freename(ep->e_name);
ep->e_name = savename(cp);
ep->e_namlen = strlen(cp);
if (strcmp(gentempname(ep), ep->e_name) == 0)
ep->e_flags |= TMPNAME;
else
ep->e_flags &= ~TMPNAME;
}
/*
* Remove an entry in the tree structure
*/
static void
removeentry(struct entry *ep)
{
struct entry *np;
np = ep->e_parent;
if (np->e_entries == ep) {
np->e_entries = ep->e_sibling;
} else {
for (np = np->e_entries; np != NULL; np = np->e_sibling) {
if (np->e_sibling == ep) {
np->e_sibling = ep->e_sibling;
break;
}
}
if (np == NULL)
badentry(ep, "cannot find entry in parent list");
}
}
/*
* Table of unused string entries, sorted by length.
*
* Entries are allocated in STRTBLINCR sized pieces so that names
* of similar lengths can use the same entry. The value of STRTBLINCR
* is chosen so that every entry has at least enough space to hold
* a "struct strtbl" header. Thus every entry can be linked onto an
* appropriate free list.
*
* NB. The macro "allocsize" below assumes that "struct strhdr"
* has a size that is a power of two.
*/
struct strhdr {
struct strhdr *next;
};
#define STRTBLINCR (sizeof(struct strhdr))
#define allocsize(size) (((size) + 1 + STRTBLINCR - 1) & ~(STRTBLINCR - 1))
static struct strhdr strtblhdr[allocsize(NAME_MAX) / STRTBLINCR];
/*
* Allocate space for a name. It first looks to see if it already
* has an appropriate sized entry, and if not allocates a new one.
*/
char *
savename(char *name)
{
struct strhdr *np;
long len;
char *cp;
if (name == NULL)
panic("bad name\n");
len = strlen(name);
np = strtblhdr[len / STRTBLINCR].next;
if (np != NULL) {
strtblhdr[len / STRTBLINCR].next = np->next;
cp = (char *)np;
} else {
cp = malloc((unsigned)allocsize(len));
if (cp == NULL)
panic("no space for string table\n");
}
(void) strcpy(cp, name);
return (cp);
}
/*
* Free space for a name. The resulting entry is linked onto the
* appropriate free list.
*/
void
freename(char *name)
{
struct strhdr *tp, *np;
tp = &strtblhdr[strlen(name) / STRTBLINCR];
np = (struct strhdr *)name;
np->next = tp->next;
tp->next = np;
}
/*
* Useful quantities placed at the end of a dumped symbol table.
*/
struct symtableheader {
int32_t volno;
int32_t stringsize;
int32_t entrytblsize;
time_t dumptime;
time_t dumpdate;
ino_t maxino;
int32_t ntrec;
};
/*
* dump a snapshot of the symbol table
*/
void
dumpsymtable(char *filename, long checkpt)
{
struct entry *ep, *tep;
ino_t i;
struct entry temp, *tentry;
long mynum = 1, stroff = 0;
FILE *fd;
struct symtableheader hdr;
vprintf(stdout, "Checkpointing the restore\n");
if (Nflag)
return;
if ((fd = fopen(filename, "w")) == NULL) {
fprintf(stderr, "fopen: %s\n", strerror(errno));
panic("cannot create save file %s for symbol table\n",
filename);
done(1);
}
clearerr(fd);
/*
* Assign indices to each entry
* Write out the string entries
*/
for (i = WINO; i <= maxino; i++) {
for (ep = lookupino(i); ep != NULL; ep = ep->e_links) {
ep->e_index = mynum++;
(void) fwrite(ep->e_name, sizeof(char),
(int)allocsize(ep->e_namlen), fd);
}
}
/*
* Convert pointers to indexes, and output
*/
tep = &temp;
stroff = 0;
for (i = WINO; i <= maxino; i++) {
for (ep = lookupino(i); ep != NULL; ep = ep->e_links) {
memmove(tep, ep, (long)sizeof(struct entry));
tep->e_name = (char *)stroff;
stroff += allocsize(ep->e_namlen);
tep->e_parent = (struct entry *)ep->e_parent->e_index;
if (ep->e_links != NULL)
tep->e_links =
(struct entry *)ep->e_links->e_index;
if (ep->e_sibling != NULL)
tep->e_sibling =
(struct entry *)ep->e_sibling->e_index;
if (ep->e_entries != NULL)
tep->e_entries =
(struct entry *)ep->e_entries->e_index;
if (ep->e_next != NULL)
tep->e_next =
(struct entry *)ep->e_next->e_index;
(void) fwrite((char *)tep, sizeof(struct entry), 1, fd);
}
}
/*
* Convert entry pointers to indexes, and output
*/
for (i = 0; i < entrytblsize; i++) {
if (entry[i] == NULL)
tentry = NULL;
else
tentry = (struct entry *)entry[i]->e_index;
(void) fwrite((char *)&tentry, sizeof(struct entry *), 1, fd);
}
hdr.volno = checkpt;
hdr.maxino = maxino;
hdr.entrytblsize = entrytblsize;
hdr.stringsize = stroff;
hdr.dumptime = dumptime;
hdr.dumpdate = dumpdate;
hdr.ntrec = ntrec;
(void) fwrite((char *)&hdr, sizeof(struct symtableheader), 1, fd);
if (ferror(fd)) {
fprintf(stderr, "fwrite: %s\n", strerror(errno));
panic("output error to file %s writing symbol table\n",
filename);
}
(void) fclose(fd);
}
/*
* Initialize a symbol table from a file
*/
void
initsymtable(char *filename)
{
char *base;
long tblsize;
struct entry *ep;
struct entry *baseep, *lep;
struct symtableheader hdr;
struct stat stbuf;
long i;
int fd;
vprintf(stdout, "Initialize symbol table.\n");
if (filename == NULL) {
entrytblsize = maxino / HASHFACTOR;
entry = (struct entry **)
calloc((unsigned)entrytblsize, sizeof(struct entry *));
if (entry == (struct entry **)NULL)
panic("no memory for entry table\n");
ep = addentry(".", ROOTINO, NODE);
ep->e_flags |= NEW;
return;
}
if ((fd = open(filename, O_RDONLY, 0)) < 0) {
fprintf(stderr, "open: %s\n", strerror(errno));
panic("cannot open symbol table file %s\n", filename);
}
if (fstat(fd, &stbuf) < 0) {
fprintf(stderr, "stat: %s\n", strerror(errno));
panic("cannot stat symbol table file %s\n", filename);
}
tblsize = stbuf.st_size - sizeof(struct symtableheader);
base = calloc(sizeof(char), (unsigned)tblsize);
if (base == NULL)
panic("cannot allocate space for symbol table\n");
if (read(fd, base, (int)tblsize) < 0 ||
read(fd, (char *)&hdr, sizeof(struct symtableheader)) < 0) {
fprintf(stderr, "read: %s\n", strerror(errno));
panic("cannot read symbol table file %s\n", filename);
}
switch (command) {
case 'r':
/*
* For normal continuation, insure that we are using
* the next incremental tape
*/
if (hdr.dumpdate != dumptime) {
if (hdr.dumpdate < dumptime)
fprintf(stderr, "Incremental tape too low\n");
else
fprintf(stderr, "Incremental tape too high\n");
done(1);
}
break;
case 'R':
/*
* For restart, insure that we are using the same tape
*/
curfile.action = SKIP;
dumptime = hdr.dumptime;
dumpdate = hdr.dumpdate;
if (!bflag)
newtapebuf(hdr.ntrec);
getvol(hdr.volno);
break;
default:
panic("initsymtable called from command %c\n", command);
break;
}
maxino = hdr.maxino;
entrytblsize = hdr.entrytblsize;
entry = (struct entry **)
(base + tblsize - (entrytblsize * sizeof(struct entry *)));
baseep = (struct entry *)(base + hdr.stringsize - sizeof(struct entry));
lep = (struct entry *)entry;
for (i = 0; i < entrytblsize; i++) {
if (entry[i] == NULL)
continue;
entry[i] = &baseep[(long)entry[i]];
}
for (ep = &baseep[1]; ep < lep; ep++) {
ep->e_name = base + (long)ep->e_name;
ep->e_parent = &baseep[(long)ep->e_parent];
if (ep->e_sibling != NULL)
ep->e_sibling = &baseep[(long)ep->e_sibling];
if (ep->e_links != NULL)
ep->e_links = &baseep[(long)ep->e_links];
if (ep->e_entries != NULL)
ep->e_entries = &baseep[(long)ep->e_entries];
if (ep->e_next != NULL)
ep->e_next = &baseep[(long)ep->e_next];
}
}