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-rw-r--r--fuse/dircache.c400
1 files changed, 0 insertions, 400 deletions
diff --git a/fuse/dircache.c b/fuse/dircache.c
deleted file mode 100644
index 771e3133..00000000
--- a/fuse/dircache.c
+++ /dev/null
@@ -1,400 +0,0 @@
-/* guestmount - mount guests using libguestfs and FUSE
- * Copyright (C) 2009 Red Hat Inc.
- *
- * 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 2 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, write to the Free Software
- * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
- *
- * Derived from the example program 'fusexmp.c':
- * Copyright (C) 2001-2007 Miklos Szeredi <miklos@szeredi.hu>
- *
- * This program can be distributed under the terms of the GNU GPL.
- * See the file COPYING.
- */
-
-#include <config.h>
-
-#include <stdio.h>
-#include <stdlib.h>
-#include <string.h>
-#include <time.h>
-#include <assert.h>
-#include <sys/time.h>
-#include <sys/types.h>
-
-#include <guestfs.h>
-
-#include "hash.h"
-#include "hash-pjw.h"
-
-#include "guestmount.h"
-#include "dircache.h"
-
-/* Note on attribute caching: FUSE can cache filesystem attributes for
- * short periods of time (configurable via -o attr_timeout). It
- * doesn't cache xattrs, and in any case FUSE caching doesn't solve
- * the problem that we have to make a series of guestfs_lstat and
- * guestfs_lgetxattr calls when we first list a directory (thus, many
- * round trips).
- *
- * For this reason, we also implement a readdir cache here which is
- * invoked when a readdir call is made. readdir is modified so that
- * as well as reading the directory, it also requests all the stat
- * structures, xattrs and readlinks of all entries in the directory,
- * and these are added to the cache here (for a short, configurable
- * period of time) in anticipation that they will be needed
- * immediately afterwards, which is usually the case when the user is
- * doing an "ls"-like operation.
- *
- * You can still use FUSE attribute caching on top of this mechanism
- * if you like.
- */
-
-struct lsc_entry { /* lstat cache entry */
- char *pathname; /* full path to the file */
- time_t timeout; /* when this entry expires */
- struct stat statbuf; /* statbuf */
-};
-
-struct xac_entry { /* xattr cache entry */
- /* NB first two fields must be same as lsc_entry */
- char *pathname; /* full path to the file */
- time_t timeout; /* when this entry expires */
- struct guestfs_xattr_list *xattrs;
-};
-
-struct rlc_entry { /* readlink cache entry */
- /* NB first two fields must be same as lsc_entry */
- char *pathname; /* full path to the file */
- time_t timeout; /* when this entry expires */
- char *link;
-};
-
-static size_t
-gen_hash (void const *x, size_t table_size)
-{
- struct lsc_entry const *p = x;
- return hash_pjw (p->pathname, table_size);
-}
-
-static bool
-gen_compare (void const *x, void const *y)
-{
- struct lsc_entry const *a = x;
- struct lsc_entry const *b = y;
- return STREQ (a->pathname, b->pathname);
-}
-
-static void
-lsc_free (void *x)
-{
- if (x) {
- struct lsc_entry *p = x;
-
- free (p->pathname);
- free (p);
- }
-}
-
-static void
-xac_free (void *x)
-{
- if (x) {
- struct xac_entry *p = x;
-
- guestfs_free_xattr_list (p->xattrs);
- lsc_free (x);
- }
-}
-
-static void
-rlc_free (void *x)
-{
- if (x) {
- struct rlc_entry *p = x;
-
- free (p->link);
- lsc_free (x);
- }
-}
-
-static Hash_table *lsc_ht, *xac_ht, *rlc_ht;
-
-void
-init_dir_caches (void)
-{
- lsc_ht = hash_initialize (1024, NULL, gen_hash, gen_compare, lsc_free);
- xac_ht = hash_initialize (1024, NULL, gen_hash, gen_compare, xac_free);
- rlc_ht = hash_initialize (1024, NULL, gen_hash, gen_compare, rlc_free);
- if (!lsc_ht || !xac_ht || !rlc_ht) {
- fprintf (stderr, "guestmount: could not initialize dir cache hashtables\n");
- exit (EXIT_FAILURE);
- }
-}
-
-void
-free_dir_caches (void)
-{
- hash_free (lsc_ht);
- hash_free (xac_ht);
- hash_free (rlc_ht);
-}
-
-struct gen_remove_data {
- time_t now;
- Hash_table *ht;
- Hash_data_freer freer;
-};
-
-static bool
-gen_remove_if_expired (void *x, void *data)
-{
- /* XXX hash_do_for_each was observed calling this function
- * with x == NULL.
- */
- if (x) {
- struct lsc_entry *p = x;
- struct gen_remove_data *d = data;
-
- if (p->timeout < d->now) {
- if (verbose)
- fprintf (stderr, "dir cache: expiring entry %p (%s)\n",
- p, p->pathname);
- d->freer (hash_delete (d->ht, x));
- }
- }
-
- return 1;
-}
-
-static void
-gen_remove_all_expired (Hash_table *ht, Hash_data_freer freer, time_t now)
-{
- struct gen_remove_data data;
- data.now = now;
- data.ht = ht;
- data.freer = freer;
-
- /* Careful reading of the documentation to hash _seems_ to indicate
- * that this is safe, _provided_ we use the default thresholds (in
- * particular, no shrink threshold).
- */
- hash_do_for_each (ht, gen_remove_if_expired, &data);
-}
-
-void
-dir_cache_remove_all_expired (time_t now)
-{
- gen_remove_all_expired (lsc_ht, lsc_free, now);
- gen_remove_all_expired (xac_ht, xac_free, now);
- gen_remove_all_expired (rlc_ht, rlc_free, now);
-}
-
-static int
-gen_replace (Hash_table *ht, struct lsc_entry *new_entry, Hash_data_freer freer)
-{
- struct lsc_entry *old_entry;
-
- old_entry = hash_delete (ht, new_entry);
- freer (old_entry);
-
- if (verbose && old_entry)
- fprintf (stderr, "dir cache: this entry replaced old entry %p (%s)\n",
- old_entry, old_entry->pathname);
-
- old_entry = hash_insert (ht, new_entry);
- if (old_entry == NULL) {
- perror ("hash_insert");
- freer (new_entry);
- return -1;
- }
- assert (old_entry == new_entry);
-
- return 0;
-}
-
-int
-lsc_insert (const char *path, const char *name, time_t now,
- struct stat const *statbuf)
-{
- struct lsc_entry *entry;
-
- entry = malloc (sizeof *entry);
- if (entry == NULL) {
- perror ("malloc");
- return -1;
- }
-
- size_t len = strlen (path) + strlen (name) + 2;
- entry->pathname = malloc (len);
- if (entry->pathname == NULL) {
- perror ("malloc");
- free (entry);
- return -1;
- }
- if (STREQ (path, "/"))
- snprintf (entry->pathname, len, "/%s", name);
- else
- snprintf (entry->pathname, len, "%s/%s", path, name);
-
- memcpy (&entry->statbuf, statbuf, sizeof entry->statbuf);
-
- entry->timeout = now + dir_cache_timeout;
-
- if (verbose)
- fprintf (stderr, "dir cache: inserting lstat entry %p (%s)\n",
- entry, entry->pathname);
-
- return gen_replace (lsc_ht, entry, lsc_free);
-}
-
-int
-xac_insert (const char *path, const char *name, time_t now,
- struct guestfs_xattr_list *xattrs)
-{
- struct xac_entry *entry;
-
- entry = malloc (sizeof *entry);
- if (entry == NULL) {
- perror ("malloc");
- return -1;
- }
-
- size_t len = strlen (path) + strlen (name) + 2;
- entry->pathname = malloc (len);
- if (entry->pathname == NULL) {
- perror ("malloc");
- free (entry);
- return -1;
- }
- if (STREQ (path, "/"))
- snprintf (entry->pathname, len, "/%s", name);
- else
- snprintf (entry->pathname, len, "%s/%s", path, name);
-
- entry->xattrs = xattrs;
-
- entry->timeout = now + dir_cache_timeout;
-
- if (verbose)
- fprintf (stderr, "dir cache: inserting xattr entry %p (%s)\n",
- entry, entry->pathname);
-
- return gen_replace (xac_ht, (struct lsc_entry *) entry, xac_free);
-}
-
-int
-rlc_insert (const char *path, const char *name, time_t now,
- char *link)
-{
- struct rlc_entry *entry;
-
- entry = malloc (sizeof *entry);
- if (entry == NULL) {
- perror ("malloc");
- return -1;
- }
-
- size_t len = strlen (path) + strlen (name) + 2;
- entry->pathname = malloc (len);
- if (entry->pathname == NULL) {
- perror ("malloc");
- free (entry);
- return -1;
- }
- if (STREQ (path, "/"))
- snprintf (entry->pathname, len, "/%s", name);
- else
- snprintf (entry->pathname, len, "%s/%s", path, name);
-
- entry->link = link;
-
- entry->timeout = now + dir_cache_timeout;
-
- if (verbose)
- fprintf (stderr, "dir cache: inserting readlink entry %p (%s)\n",
- entry, entry->pathname);
-
- return gen_replace (rlc_ht, (struct lsc_entry *) entry, rlc_free);
-}
-
-const struct stat *
-lsc_lookup (const char *pathname)
-{
- const struct lsc_entry key = { .pathname = bad_cast (pathname) };
- struct lsc_entry *entry;
- time_t now;
-
- time (&now);
-
- entry = hash_lookup (lsc_ht, &key);
- if (entry && entry->timeout >= now)
- return &entry->statbuf;
- else
- return NULL;
-}
-
-const struct guestfs_xattr_list *
-xac_lookup (const char *pathname)
-{
- const struct xac_entry key = { .pathname = bad_cast (pathname) };
- struct xac_entry *entry;
- time_t now;
-
- time (&now);
-
- entry = hash_lookup (xac_ht, &key);
- if (entry && entry->timeout >= now)
- return entry->xattrs;
- else
- return NULL;
-}
-
-const char *
-rlc_lookup (const char *pathname)
-{
- const struct rlc_entry key = { .pathname = bad_cast (pathname) };
- struct rlc_entry *entry;
- time_t now;
-
- time (&now);
-
- entry = hash_lookup (rlc_ht, &key);
- if (entry && entry->timeout >= now)
- return entry->link;
- else
- return NULL;
-}
-
-static void
-lsc_remove (Hash_table *ht, const char *pathname, Hash_data_freer freer)
-{
- const struct lsc_entry key = { .pathname = bad_cast (pathname) };
- struct lsc_entry *entry;
-
- entry = hash_delete (ht, &key);
-
- if (verbose && entry)
- fprintf (stderr, "dir cache: invalidating entry %p (%s)\n",
- entry, entry->pathname);
-
- freer (entry);
-}
-
-void
-dir_cache_invalidate (const char *path)
-{
- lsc_remove (lsc_ht, path, lsc_free);
- lsc_remove (xac_ht, path, xac_free);
- lsc_remove (rlc_ht, path, rlc_free);
-}
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