File: [local] / src / usr.sbin / makefs / walk.c (download)
Revision 1.12, Sat Aug 19 04:21:06 2023 UTC (9 months, 3 weeks ago) by guenther
Branch: MAIN
CVS Tags: OPENBSD_7_5_BASE, OPENBSD_7_5, OPENBSD_7_4_BASE, OPENBSD_7_4, HEAD Changes since 1.11: +5 -7 lines
Copy entire st_*tim structs at once, rather than copying
the st_*time and (obsolete) st_*timensec members separately.
ok millert@
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/* $OpenBSD: walk.c,v 1.12 2023/08/19 04:21:06 guenther Exp $ */
/* $NetBSD: walk.c,v 1.29 2015/11/25 00:48:49 christos Exp $ */
/*
* Copyright (c) 2001 Wasabi Systems, Inc.
* All rights reserved.
*
* Written by Luke Mewburn for Wasabi Systems, Inc.
*
* 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. All advertising materials mentioning features or use of this software
* must display the following acknowledgement:
* This product includes software developed for the NetBSD Project by
* Wasabi Systems, Inc.
* 4. The name of Wasabi Systems, Inc. may not be used to endorse
* or promote products derived from this software without specific prior
* written permission.
*
* THIS SOFTWARE IS PROVIDED BY WASABI SYSTEMS, INC. ``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 WASABI SYSTEMS, INC
* 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/types.h>
#include <sys/stat.h>
#include <assert.h>
#include <stdio.h>
#include <dirent.h>
#include <stdlib.h>
#include <limits.h>
#include <string.h>
#include <unistd.h>
#include "makefs.h"
static fsnode *create_fsnode(const char *, const char *, const char *,
struct stat *);
static fsinode *link_check(fsinode *);
/*
* walk_dir --
* build a tree of fsnodes from `root' and `dir', with a parent
* fsnode of `parent' (which may be NULL for the root of the tree).
* append the tree to a fsnode of `join' if it is not NULL.
* each "level" is a directory, with the "." entry guaranteed to be
* at the start of the list, and without ".." entries.
*/
fsnode *
walk_dir(const char *root, const char *dir, fsnode *parent, fsnode *join)
{
fsnode *first, *cur, *prev, *last;
DIR *dirp;
struct dirent *dent;
char path[PATH_MAX+1];
struct stat stbuf;
char *name, *rp;
int dot, len;
assert(root != NULL);
assert(dir != NULL);
len = snprintf(path, sizeof(path), "%s/%s", root, dir);
if (len >= (int)sizeof(path))
errx(1, "Pathname too long.");
if ((dirp = opendir(path)) == NULL)
err(1, "Can't opendir `%s'", path);
rp = path + strlen(root) + 1;
if (join != NULL) {
first = cur = join;
while (cur->next != NULL)
cur = cur->next;
prev = last = cur;
} else
last = first = prev = NULL;
while ((dent = readdir(dirp)) != NULL) {
name = dent->d_name;
dot = 0;
if (name[0] == '.')
switch (name[1]) {
case '\0': /* "." */
if (join != NULL)
continue;
dot = 1;
break;
case '.': /* ".." */
if (name[2] == '\0')
continue;
/* FALLTHROUGH */
default:
dot = 0;
}
if (snprintf(path + len, sizeof(path) - len, "/%s", name) >=
(int)sizeof(path) - len)
errx(1, "Pathname too long.");
if (lstat(path, &stbuf) == -1)
err(1, "Can't lstat `%s'", path);
if (S_ISSOCK(stbuf.st_mode & S_IFMT))
continue;
if (join != NULL) {
cur = join->next;
for (;;) {
if (cur == NULL || strcmp(cur->name, name) == 0)
break;
if (cur == last) {
cur = NULL;
break;
}
cur = cur->next;
}
if (cur != NULL) {
if (S_ISDIR(cur->type) &&
S_ISDIR(stbuf.st_mode)) {
cur->child = walk_dir(root, rp, cur,
cur->child);
continue;
}
errx(1, "Can't merge %s `%s' with "
"existing %s",
inode_type(stbuf.st_mode), path,
inode_type(cur->type));
}
}
cur = create_fsnode(root, dir, name, &stbuf);
cur->parent = parent;
if (dot) {
/* ensure "." is at the start of the list */
cur->next = first;
first = cur;
if (! prev)
prev = cur;
cur->first = first;
} else { /* not "." */
if (prev)
prev->next = cur;
prev = cur;
if (!first)
first = cur;
cur->first = first;
if (S_ISDIR(cur->type)) {
cur->child = walk_dir(root, rp, cur, NULL);
continue;
}
}
if (stbuf.st_nlink > 1) {
fsinode *curino;
curino = link_check(cur->inode);
if (curino != NULL) {
free(cur->inode);
cur->inode = curino;
cur->inode->nlink++;
}
}
if (S_ISLNK(cur->type)) {
char slink[PATH_MAX+1];
int llen;
llen = readlink(path, slink, sizeof(slink) - 1);
if (llen == -1)
err(1, "Readlink `%s'", path);
slink[llen] = '\0';
cur->symlink = estrdup(slink);
}
}
assert(first != NULL);
if (join == NULL)
for (cur = first->next; cur != NULL; cur = cur->next)
cur->first = first;
if (closedir(dirp) == -1)
err(1, "Can't closedir `%s/%s'", root, dir);
return (first);
}
static fsnode *
create_fsnode(const char *root, const char *path, const char *name,
struct stat *stbuf)
{
fsnode *cur;
cur = ecalloc(1, sizeof(*cur));
cur->path = estrdup(path);
cur->name = estrdup(name);
cur->inode = ecalloc(1, sizeof(*cur->inode));
cur->root = root;
cur->type = stbuf->st_mode & S_IFMT;
cur->inode->nlink = 1;
cur->inode->st = *stbuf;
if (Tflag) {
cur->inode->st.st_atim.tv_sec = stampts;
cur->inode->st.st_atim.tv_nsec = 0;
cur->inode->st.st_mtim = cur->inode->st.st_ctim =
cur->inode->st.st_atim;
}
return (cur);
}
/*
* free_fsnodes --
* Removes node from tree and frees it and all of
* its descendants.
*/
void
free_fsnodes(fsnode *node)
{
fsnode *cur, *next;
assert(node != NULL);
/* for ".", start with actual parent node */
if (node->first == node) {
assert(node->name[0] == '.' && node->name[1] == '\0');
if (node->parent) {
assert(node->parent->child == node);
node = node->parent;
}
}
/* Find ourselves in our sibling list and unlink */
if (node->first != node) {
for (cur = node->first; cur->next; cur = cur->next) {
if (cur->next == node) {
cur->next = node->next;
node->next = NULL;
break;
}
}
}
for (cur = node; cur != NULL; cur = next) {
next = cur->next;
if (cur->child) {
cur->child->parent = NULL;
free_fsnodes(cur->child);
}
if (cur->inode->nlink-- == 1)
free(cur->inode);
if (cur->symlink)
free(cur->symlink);
free(cur->path);
free(cur->name);
free(cur);
}
}
/*
* inode_type --
* for a given inode type `mode', return a descriptive string.
* for most cases, uses inotype() from mtree/misc.c
*/
const char *
inode_type(mode_t mode)
{
switch (mode & S_IFMT) {
case S_IFBLK:
return ("block");
case S_IFCHR:
return ("char");
case S_IFDIR:
return ("dir");
case S_IFIFO:
return ("fifo");
case S_IFREG:
return ("file");
case S_IFLNK:
return ("symlink");
case S_IFSOCK:
return ("socket");
default:
return ("unknown");
}
}
/*
* link_check --
* return pointer to fsinode matching `entry's st_ino & st_dev if it exists,
* otherwise add `entry' to table and return NULL
*/
/* This was borrowed from du.c and tweaked to keep an fsnode
* pointer instead. -- dbj@netbsd.org
*/
static fsinode *
link_check(fsinode *entry)
{
static struct entry {
fsinode *data;
} *htable;
static int htshift; /* log(allocated size) */
static int htmask; /* allocated size - 1 */
static int htused; /* 2*number of insertions */
int h, h2;
uint64_t tmp;
/* this constant is (1<<64)/((1+sqrt(5))/2)
* aka (word size)/(golden ratio)
*/
const uint64_t HTCONST = 11400714819323198485ULL;
const int HTBITS = 64;
/* Never store zero in hashtable */
assert(entry);
/* Extend hash table if necessary, keep load under 0.5 */
if (htused<<1 >= htmask) {
struct entry *ohtable;
if (!htable)
htshift = 10; /* starting hashtable size */
else
htshift++; /* exponential hashtable growth */
htmask = (1 << htshift) - 1;
htused = 0;
ohtable = htable;
htable = ecalloc(htmask+1, sizeof(*htable));
/* populate newly allocated hashtable */
if (ohtable) {
int i;
for (i = 0; i <= htmask>>1; i++)
if (ohtable[i].data)
link_check(ohtable[i].data);
free(ohtable);
}
}
/* multiplicative hashing */
tmp = entry->st.st_dev;
tmp <<= HTBITS>>1;
tmp |= entry->st.st_ino;
tmp *= HTCONST;
h = tmp >> (HTBITS - htshift);
h2 = 1 | ( tmp >> (HTBITS - (htshift<<1) - 1)); /* must be odd */
/* open address hashtable search with double hash probing */
while (htable[h].data) {
if ((htable[h].data->st.st_ino == entry->st.st_ino) &&
(htable[h].data->st.st_dev == entry->st.st_dev)) {
return htable[h].data;
}
h = (h + h2) & htmask;
}
/* Insert the current entry into hashtable */
htable[h].data = entry;
htused++;
return NULL;
}