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GCC Code Coverage Report

Directory:	./		Exec	Total	Coverage
File:	sbin/restore/symtab.c	Lines:	0	270	0.0 %
Date:	2017-11-13	Branches:	0	183	0.0 %


/*	$OpenBSD: symtab.c,v 1.22 2015/01/16 06:40:00 deraadt Exp $	*/
/*	$NetBSD: symtab.c,v 1.10 1997/03/19 08:42:54 lukem Exp $	*/

/*
 * 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.
 * 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.
 */

/*
 * 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/stat.h>

#include <ufs/ufs/dinode.h>

#include <err.h>
#include <fcntl.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <unistd.h>
#include <limits.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 < ROOTINO || 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 < ROOTINO || inum >= maxino)
		panic("addino: out of range %llu\n",
		    (unsigned long long)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 < ROOTINO || inum >= maxino)
		panic("deleteino: out of range %llu\n",
		    (unsigned long long)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: %llu not found\n", (unsigned long long)inum);
}

/*
 * Look up an entry by name
 */
struct entry *
lookupname(char *name)
{
	struct entry *ep;
	char *np, *cp;
	char buf[PATH_MAX];

	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[PATH_MAX];

	for (cp = &namebuf[PATH_MAX - 2]; cp > &namebuf[ep->e_namlen]; ) {
		cp -= ep->e_namlen;
		memcpy(cp, ep->e_name, 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 freelist
 * 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, sizeof(struct entry));
	} else {
		np = 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
 * apprpriate 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(allocsize(len));
		if (cp == NULL)
			panic("no space for string table\n");
	}
	(void)strlcpy(cp, name, len + 1);
	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 *fp;
	struct symtableheader hdr;

	Vprintf(stdout, "Check pointing the restore\n");
	if (Nflag)
		return;
	if ((fp = fopen(filename, "w")) == NULL) {
		warn("fopen");
		panic("cannot create save file %s for symbol table\n",
		    filename);
	}
	clearerr(fp);
	/*
	 * Assign indices to each entry
	 * Write out the string entries
	 */
	for (i = ROOTINO; 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), fp);
		}
	}
	/*
	 * Convert pointers to indexes, and output
	 */
	tep = &temp;
	stroff = 0;
	for (i = ROOTINO; i <= maxino; i++) {
		for (ep = lookupino(i); ep != NULL; ep = ep->e_links) {
			memcpy(tep, ep, 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, fp);
		}
	}
	/*
	 * 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, fp);
	}
	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, fp);
	if (ferror(fp)) {
		warn("fwrite");
		panic("output error to file %s writing symbol table\n",
		    filename);
	}
	(void)fclose(fp);
}

/*
 * 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 = calloc(entrytblsize, sizeof(struct entry *));
		if (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) {
		warn("open");
		panic("cannot open symbol table file %s\n", filename);
	}
	if (fstat(fd, &stbuf) < 0) {
		warn("stat");
		panic("cannot stat symbol table file %s\n", filename);
	}
	tblsize = stbuf.st_size - sizeof(struct symtableheader);
	base = calloc(tblsize, sizeof(char));
	if (base == NULL)
		panic("cannot allocate space for symbol table\n");
	if (read(fd, base, tblsize) < 0 ||
	    read(fd, &hdr, sizeof(struct symtableheader)) < 0) {
		warn("read");
		panic("cannot read symbol table file %s\n", filename);
	}
	close(fd);
	switch (command) {
	case 'r':
		/*
		 * For normal continuation, insure that we are using
		 * the next incremental tape
		 */
		if (hdr.dumpdate != dumptime)
			errx(1, "Incremental tape too %s",
			    (hdr.dumpdate < dumptime) ? "low" : "high");
		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];
	}
}


Generated by: GCOVR (Version 3.3)

Line	Branch	Exec	Source
1			/* $OpenBSD: symtab.c,v 1.22 2015/01/16 06:40:00 deraadt Exp $ */
2			/* $NetBSD: symtab.c,v 1.10 1997/03/19 08:42:54 lukem Exp $ */
3
4			/*
5			* Copyright (c) 1983, 1993
6			* The Regents of the University of California. All rights reserved.
7			*
8			* Redistribution and use in source and binary forms, with or without
9			* modification, are permitted provided that the following conditions
10			* are met:
11			* 1. Redistributions of source code must retain the above copyright
12			* notice, this list of conditions and the following disclaimer.
13			* 2. Redistributions in binary form must reproduce the above copyright
14			* notice, this list of conditions and the following disclaimer in the
15			* documentation and/or other materials provided with the distribution.
16			* 3. Neither the name of the University nor the names of its contributors
17			* may be used to endorse or promote products derived from this software
18			* without specific prior written permission.
19			*
20			* THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
21			* ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
22			* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
23			* ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
24			* FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
25			* DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
26			* OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
27			* HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
28			* LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
29			* OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
30			* SUCH DAMAGE.
31			*/
32
33			/*
34			* These routines maintain the symbol table which tracks the state
35			* of the file system being restored. They provide lookup by either
36			* name or inode number. They also provide for creation, deletion,
37			* and renaming of entries. Because of the dynamic nature of pathnames,
38			* names should not be saved, but always constructed just before they
39			* are needed, by calling "myname".
40			*/
41
42			#include <sys/stat.h>
43
44			#include <ufs/ufs/dinode.h>
45
46			#include <err.h>
47			#include <fcntl.h>
48			#include <stdio.h>
49			#include <stdlib.h>
50			#include <string.h>
51			#include <unistd.h>
52			#include <limits.h>
53
54			#include "restore.h"
55			#include "extern.h"
56
57			/*
58			* The following variables define the inode symbol table.
59			* The primary hash table is dynamically allocated based on
60			* the number of inodes in the file system (maxino), scaled by
61			* HASHFACTOR. The variable "entry" points to the hash table;
62			* the variable "entrytblsize" indicates its size (in entries).
63			*/
64			#define HASHFACTOR 5
65			static struct entry **entry;
66			static long entrytblsize;
67
68			static void addino(ino_t, struct entry *);
69			static struct entry lookupparent(char );
70			static void removeentry(struct entry *);
71
72			/*
73			* Look up an entry by inode number
74			*/
75			struct entry *
76			lookupino(ino_t inum)
77			{
78			struct entry *ep;
79
80			if (inum < ROOTINO \|\| inum >= maxino)
81			return (NULL);
82			for (ep = entry[inum % entrytblsize]; ep != NULL; ep = ep->e_next)
83			if (ep->e_ino == inum)
84			return (ep);
85			return (NULL);
86			}
87
88			/*
89			* Add an entry into the entry table
90			*/
91			static void
92			addino(ino_t inum, struct entry *np)
93			{
94			struct entry **epp;
95
96			if (inum < ROOTINO \|\| inum >= maxino)
97			panic("addino: out of range %llu\n",
98			(unsigned long long)inum);
99			epp = &entry[inum % entrytblsize];
100			np->e_ino = inum;
101			np->e_next = *epp;
102			*epp = np;
103			if (dflag)
104			for (np = np->e_next; np != NULL; np = np->e_next)
105			if (np->e_ino == inum)
106			badentry(np, "duplicate inum");
107			}
108
109			/*
110			* Delete an entry from the entry table
111			*/
112			void
113			deleteino(ino_t inum)
114			{
115			struct entry *next;
116			struct entry **prev;
117
118			if (inum < ROOTINO \|\| inum >= maxino)
119			panic("deleteino: out of range %llu\n",
120			(unsigned long long)inum);
121			prev = &entry[inum % entrytblsize];
122			for (next = *prev; next != NULL; next = next->e_next) {
123			if (next->e_ino == inum) {
124			next->e_ino = 0;
125			*prev = next->e_next;
126			return;
127			}
128			prev = &next->e_next;
129			}
130			panic("deleteino: %llu not found\n", (unsigned long long)inum);
131			}
132
133			/*
134			* Look up an entry by name
135			*/
136			struct entry *
137			lookupname(char *name)
138			{
139			struct entry *ep;
140			char np, cp;
141			char buf[PATH_MAX];
142
143			cp = name;
144			for (ep = lookupino(ROOTINO); ep != NULL; ep = ep->e_entries) {
145			for (np = buf;
146			cp != '/' && cp != '\0' && np < &buf[sizeof(buf)]; )
147			np++ = cp++;
148			if (np == &buf[sizeof(buf)])
149			break;
150			*np = '\0';
151			for ( ; ep != NULL; ep = ep->e_sibling)
152			if (strcmp(ep->e_name, buf) == 0)
153			break;
154			if (ep == NULL)
155			break;
156			if (*cp++ == '\0')
157			return (ep);
158			}
159			return (NULL);
160			}
161
162			/*
163			* Look up the parent of a pathname
164			*/
165			static struct entry *
166			lookupparent(char *name)
167			{
168			struct entry *ep;
169			char *tailindex;
170
171			tailindex = strrchr(name, '/');
172			if (tailindex == NULL)
173			return (NULL);
174			*tailindex = '\0';
175			ep = lookupname(name);
176			*tailindex = '/';
177			if (ep == NULL)
178			return (NULL);
179			if (ep->e_type != NODE)
180			panic("%s is not a directory\n", name);
181			return (ep);
182			}
183
184			/*
185			* Determine the current pathname of a node or leaf
186			*/
187			char *
188			myname(struct entry *ep)
189			{
190			char *cp;
191			static char namebuf[PATH_MAX];
192
193			for (cp = &namebuf[PATH_MAX - 2]; cp > &namebuf[ep->e_namlen]; ) {
194			cp -= ep->e_namlen;
195			memcpy(cp, ep->e_name, ep->e_namlen);
196			if (ep == lookupino(ROOTINO))
197			return (cp);
198			*(--cp) = '/';
199			ep = ep->e_parent;
200			}
201			panic("%s: pathname too long\n", cp);
202			return(cp);
203			}
204
205			/*
206			* Unused symbol table entries are linked together on a freelist
207			* headed by the following pointer.
208			*/
209			static struct entry *freelist = NULL;
210
211			/*
212			* add an entry to the symbol table
213			*/
214			struct entry *
215			addentry(char *name, ino_t inum, int type)
216			{
217			struct entry np, ep;
218
219			if (freelist != NULL) {
220			np = freelist;
221			freelist = np->e_next;
222			memset(np, 0, sizeof(struct entry));
223			} else {
224			np = calloc(1, sizeof(struct entry));
225			if (np == NULL)
226			panic("no memory to extend symbol table\n");
227			}
228			np->e_type = type & ~LINK;
229			ep = lookupparent(name);
230			if (ep == NULL) {
231			if (inum != ROOTINO \|\| lookupino(ROOTINO) != NULL)
232			panic("bad name to addentry %s\n", name);
233			np->e_name = savename(name);
234			np->e_namlen = strlen(name);
235			np->e_parent = np;
236			addino(ROOTINO, np);
237			return (np);
238			}
239			np->e_name = savename(strrchr(name, '/') + 1);
240			np->e_namlen = strlen(np->e_name);
241			np->e_parent = ep;
242			np->e_sibling = ep->e_entries;
243			ep->e_entries = np;
244			if (type & LINK) {
245			ep = lookupino(inum);
246			if (ep == NULL)
247			panic("link to non-existent name\n");
248			np->e_ino = inum;
249			np->e_links = ep->e_links;
250			ep->e_links = np;
251			} else if (inum != 0) {
252			if (lookupino(inum) != NULL)
253			panic("duplicate entry\n");
254			addino(inum, np);
255			}
256			return (np);
257			}
258
259			/*
260			* delete an entry from the symbol table
261			*/
262			void
263			freeentry(struct entry *ep)
264			{
265			struct entry *np;
266			ino_t inum;
267
268			if (ep->e_flags != REMOVED)
269			badentry(ep, "not marked REMOVED");
270			if (ep->e_type == NODE) {
271			if (ep->e_links != NULL)
272			badentry(ep, "freeing referenced directory");
273			if (ep->e_entries != NULL)
274			badentry(ep, "freeing non-empty directory");
275			}
276			if (ep->e_ino != 0) {
277			np = lookupino(ep->e_ino);
278			if (np == NULL)
279			badentry(ep, "lookupino failed");
280			if (np == ep) {
281			inum = ep->e_ino;
282			deleteino(inum);
283			if (ep->e_links != NULL)
284			addino(inum, ep->e_links);
285			} else {
286			for (; np != NULL; np = np->e_links) {
287			if (np->e_links == ep) {
288			np->e_links = ep->e_links;
289			break;
290			}
291			}
292			if (np == NULL)
293			badentry(ep, "link not found");
294			}
295			}
296			removeentry(ep);
297			freename(ep->e_name);
298			ep->e_next = freelist;
299			freelist = ep;
300			}
301
302			/*
303			* Relocate an entry in the tree structure
304			*/
305			void
306			moveentry(struct entry ep, char newname)
307			{
308			struct entry *np;
309			char *cp;
310
311			np = lookupparent(newname);
312			if (np == NULL)
313			badentry(ep, "cannot move ROOT");
314			if (np != ep->e_parent) {
315			removeentry(ep);
316			ep->e_parent = np;
317			ep->e_sibling = np->e_entries;
318			np->e_entries = ep;
319			}
320			cp = strrchr(newname, '/') + 1;
321			freename(ep->e_name);
322			ep->e_name = savename(cp);
323			ep->e_namlen = strlen(cp);
324			if (strcmp(gentempname(ep), ep->e_name) == 0)
325			ep->e_flags \|= TMPNAME;
326			else
327			ep->e_flags &= ~TMPNAME;
328			}
329
330			/*
331			* Remove an entry in the tree structure
332			*/
333			static void
334			removeentry(struct entry *ep)
335			{
336			struct entry *np;
337
338			np = ep->e_parent;
339			if (np->e_entries == ep) {
340			np->e_entries = ep->e_sibling;
341			} else {
342			for (np = np->e_entries; np != NULL; np = np->e_sibling) {
343			if (np->e_sibling == ep) {
344			np->e_sibling = ep->e_sibling;
345			break;
346			}
347			}
348			if (np == NULL)
349			badentry(ep, "cannot find entry in parent list");
350			}
351			}
352
353			/*
354			* Table of unused string entries, sorted by length.
355			*
356			* Entries are allocated in STRTBLINCR sized pieces so that names
357			* of similar lengths can use the same entry. The value of STRTBLINCR
358			* is chosen so that every entry has at least enough space to hold
359			* a "struct strtbl" header. Thus every entry can be linked onto an
360			* apprpriate free list.
361			*
362			* NB. The macro "allocsize" below assumes that "struct strhdr"
363			* has a size that is a power of two.
364			*/
365			struct strhdr {
366			struct strhdr *next;
367			};
368
369			#define STRTBLINCR (sizeof(struct strhdr))
370			#define allocsize(size) (((size) + 1 + STRTBLINCR - 1) & ~(STRTBLINCR - 1))
371
372			static struct strhdr strtblhdr[allocsize(NAME_MAX) / STRTBLINCR];
373
374			/*
375			* Allocate space for a name. It first looks to see if it already
376			* has an appropriate sized entry, and if not allocates a new one.
377			*/
378			char *
379			savename(char *name)
380			{
381			struct strhdr *np;
382			long len;
383			char *cp;
384
385			if (name == NULL)
386			panic("bad name\n");
387			len = strlen(name);
388			np = strtblhdr[len / STRTBLINCR].next;
389			if (np != NULL) {
390			strtblhdr[len / STRTBLINCR].next = np->next;
391			cp = (char *)np;
392			} else {
393			cp = malloc(allocsize(len));
394			if (cp == NULL)
395			panic("no space for string table\n");
396			}
397			(void)strlcpy(cp, name, len + 1);
398			return (cp);
399			}
400
401			/*
402			* Free space for a name. The resulting entry is linked onto the
403			* appropriate free list.
404			*/
405			void
406			freename(char *name)
407			{
408			struct strhdr tp, np;
409
410			tp = &strtblhdr[strlen(name) / STRTBLINCR];
411			np = (struct strhdr *)name;
412			np->next = tp->next;
413			tp->next = np;
414			}
415
416			/*
417			* Useful quantities placed at the end of a dumped symbol table.
418			*/
419			struct symtableheader {
420			int32_t volno;
421			int32_t stringsize;
422			int32_t entrytblsize;
423			time_t dumptime;
424			time_t dumpdate;
425			ino_t maxino;
426			int32_t ntrec;
427			};
428
429			/*
430			* dump a snapshot of the symbol table
431			*/
432			void
433			dumpsymtable(char *filename, long checkpt)
434			{
435			struct entry ep, tep;
436			ino_t i;
437			struct entry temp, *tentry;
438			long mynum = 1, stroff = 0;
439			FILE *fp;
440			struct symtableheader hdr;
441
442			Vprintf(stdout, "Check pointing the restore\n");
443			if (Nflag)
444			return;
445			if ((fp = fopen(filename, "w")) == NULL) {
446			warn("fopen");
447			panic("cannot create save file %s for symbol table\n",
448			filename);
449			}
450			clearerr(fp);
451			/*
452			* Assign indices to each entry
453			* Write out the string entries
454			*/
455			for (i = ROOTINO; i <= maxino; i++) {
456			for (ep = lookupino(i); ep != NULL; ep = ep->e_links) {
457			ep->e_index = mynum++;
458			(void)fwrite(ep->e_name, sizeof(char),
459			(int)allocsize(ep->e_namlen), fp);
460			}
461			}
462			/*
463			* Convert pointers to indexes, and output
464			*/
465			tep = &temp;
466			stroff = 0;
467			for (i = ROOTINO; i <= maxino; i++) {
468			for (ep = lookupino(i); ep != NULL; ep = ep->e_links) {
469			memcpy(tep, ep, sizeof(struct entry));
470			tep->e_name = (char *)stroff;
471			stroff += allocsize(ep->e_namlen);
472			tep->e_parent = (struct entry *)ep->e_parent->e_index;
473			if (ep->e_links != NULL)
474			tep->e_links =
475			(struct entry *)ep->e_links->e_index;
476			if (ep->e_sibling != NULL)
477			tep->e_sibling =
478			(struct entry *)ep->e_sibling->e_index;
479			if (ep->e_entries != NULL)
480			tep->e_entries =
481			(struct entry *)ep->e_entries->e_index;
482			if (ep->e_next != NULL)
483			tep->e_next =
484			(struct entry *)ep->e_next->e_index;
485			(void)fwrite((char *)tep, sizeof(struct entry), 1, fp);
486			}
487			}
488			/*
489			* Convert entry pointers to indexes, and output
490			*/
491			for (i = 0; i < entrytblsize; i++) {
492			if (entry[i] == NULL)
493			tentry = NULL;
494			else
495			tentry = (struct entry *)entry[i]->e_index;
496			(void)fwrite((char )&tentry, sizeof(struct entry ), 1, fp);
497			}
498			hdr.volno = checkpt;
499			hdr.maxino = maxino;
500			hdr.entrytblsize = entrytblsize;
501			hdr.stringsize = stroff;
502			hdr.dumptime = dumptime;
503			hdr.dumpdate = dumpdate;
504			hdr.ntrec = ntrec;
505			(void)fwrite((char *)&hdr, sizeof(struct symtableheader), 1, fp);
506			if (ferror(fp)) {
507			warn("fwrite");
508			panic("output error to file %s writing symbol table\n",
509			filename);
510			}
511			(void)fclose(fp);
512			}
513
514			/*
515			* Initialize a symbol table from a file
516			*/
517			void
518			initsymtable(char *filename)
519			{
520			char *base;
521			long tblsize;
522			struct entry *ep;
523			struct entry baseep, lep;
524			struct symtableheader hdr;
525			struct stat stbuf;
526			long i;
527			int fd;
528
529			Vprintf(stdout, "Initialize symbol table.\n");
530			if (filename == NULL) {
531			entrytblsize = maxino / HASHFACTOR;
532			entry = calloc(entrytblsize, sizeof(struct entry *));
533			if (entry == NULL)
534			panic("no memory for entry table\n");
535			ep = addentry(".", ROOTINO, NODE);
536			ep->e_flags \|= NEW;
537			return;
538			}
539			if ((fd = open(filename, O_RDONLY, 0)) < 0) {
540			warn("open");
541			panic("cannot open symbol table file %s\n", filename);
542			}
543			if (fstat(fd, &stbuf) < 0) {
544			warn("stat");
545			panic("cannot stat symbol table file %s\n", filename);
546			}
547			tblsize = stbuf.st_size - sizeof(struct symtableheader);
548			base = calloc(tblsize, sizeof(char));
549			if (base == NULL)
550			panic("cannot allocate space for symbol table\n");
551			if (read(fd, base, tblsize) < 0 \|\|
552			read(fd, &hdr, sizeof(struct symtableheader)) < 0) {
553			warn("read");
554			panic("cannot read symbol table file %s\n", filename);
555			}
556			close(fd);
557			switch (command) {
558			case 'r':
559			/*
560			* For normal continuation, insure that we are using
561			* the next incremental tape
562			*/
563			if (hdr.dumpdate != dumptime)
564			errx(1, "Incremental tape too %s",
565			(hdr.dumpdate < dumptime) ? "low" : "high");
566			break;
567			case 'R':
568			/*
569			* For restart, insure that we are using the same tape
570			*/
571			curfile.action = SKIP;
572			dumptime = hdr.dumptime;
573			dumpdate = hdr.dumpdate;
574			if (!bflag)
575			newtapebuf(hdr.ntrec);
576			getvol(hdr.volno);
577			break;
578			default:
579			panic("initsymtable called from command %c\n", command);
580			break;
581			}
582			maxino = hdr.maxino;
583			entrytblsize = hdr.entrytblsize;
584			entry = (struct entry **)
585			(base + tblsize - (entrytblsize * sizeof(struct entry *)));
586			baseep = (struct entry *)(base + hdr.stringsize - sizeof(struct entry));
587			lep = (struct entry *)entry;
588			for (i = 0; i < entrytblsize; i++) {
589			if (entry[i] == NULL)
590			continue;
591			entry[i] = &baseep[(long)entry[i]];
592			}
593			for (ep = &baseep[1]; ep < lep; ep++) {
594			ep->e_name = base + (long)ep->e_name;
595			ep->e_parent = &baseep[(long)ep->e_parent];
596			if (ep->e_sibling != NULL)
597			ep->e_sibling = &baseep[(long)ep->e_sibling];
598			if (ep->e_links != NULL)
599			ep->e_links = &baseep[(long)ep->e_links];
600			if (ep->e_entries != NULL)
601			ep->e_entries = &baseep[(long)ep->e_entries];
602			if (ep->e_next != NULL)
603			ep->e_next = &baseep[(long)ep->e_next];
604			}
605			}