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-rw-r--r--contrib/amd/amd/readdir.c498
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diff --git a/contrib/amd/amd/readdir.c b/contrib/amd/amd/readdir.c
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+/*
+ * Copyright (c) 1997-2006 Erez Zadok
+ * Copyright (c) 1990 Jan-Simon Pendry
+ * Copyright (c) 1990 Imperial College of Science, Technology & Medicine
+ * Copyright (c) 1990 The Regents of the University of California.
+ * All rights reserved.
+ *
+ * This code is derived from software contributed to Berkeley by
+ * Jan-Simon Pendry at Imperial College, London.
+ *
+ * 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 acknowledgment:
+ * This product includes software developed by the University of
+ * California, Berkeley and its contributors.
+ * 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.
+ *
+ *
+ * File: am-utils/amd/readdir.c
+ *
+ */
+
+
+#ifdef HAVE_CONFIG_H
+# include <config.h>
+#endif /* HAVE_CONFIG_H */
+#include <am_defs.h>
+#include <amd.h>
+
+
+/****************************************************************************
+ *** MACROS ***
+ ****************************************************************************/
+#define DOT_DOT_COOKIE (u_int) 1
+#define MAX_CHAIN 2048
+
+
+/****************************************************************************
+ *** FORWARD DEFINITIONS ***
+ ****************************************************************************/
+static int key_already_in_chain(char *keyname, const nfsentry *chain);
+static nfsentry *make_entry_chain(am_node *mp, const nfsentry *current_chain, int fully_browsable);
+static int amfs_readdir_browsable(am_node *mp, nfscookie cookie, nfsdirlist *dp, nfsentry *ep, u_int count, int fully_browsable);
+
+
+/****************************************************************************
+ *** FUNCTIONS ***
+ ****************************************************************************/
+/*
+ * Was: NEW_TOPLVL_READDIR
+ * Search a chain for an entry with some name.
+ * -Erez Zadok <ezk@cs.columbia.edu>
+ */
+static int
+key_already_in_chain(char *keyname, const nfsentry *chain)
+{
+ const nfsentry *tmpchain = chain;
+
+ while (tmpchain) {
+ if (keyname && tmpchain->ne_name && STREQ(keyname, tmpchain->ne_name))
+ return 1;
+ tmpchain = tmpchain->ne_nextentry;
+ }
+
+ return 0;
+}
+
+
+/*
+ * Create a chain of entries which are not linked.
+ * -Erez Zadok <ezk@cs.columbia.edu>
+ */
+static nfsentry *
+make_entry_chain(am_node *mp, const nfsentry *current_chain, int fully_browsable)
+{
+ static u_int last_cookie = (u_int) 2; /* monotonically increasing */
+ static nfsentry chain[MAX_CHAIN];
+ static int max_entries = MAX_CHAIN;
+ char *key;
+ int num_entries = 0, i;
+ u_int preflen = 0;
+ nfsentry *retval = (nfsentry *) NULL;
+ mntfs *mf;
+ mnt_map *mmp;
+
+ if (!mp) {
+ plog(XLOG_DEBUG, "make_entry_chain: mp is (NULL)");
+ return retval;
+ }
+ mf = mp->am_mnt;
+ if (!mf) {
+ plog(XLOG_DEBUG, "make_entry_chain: mp->am_mnt is (NULL)");
+ return retval;
+ }
+ mmp = (mnt_map *) mf->mf_private;
+ if (!mmp) {
+ plog(XLOG_DEBUG, "make_entry_chain: mp->am_mnt->mf_private is (NULL)");
+ return retval;
+ }
+
+ if (mp->am_pref)
+ preflen = strlen(mp->am_pref);
+
+ /* iterate over keys */
+ for (i = 0; i < NKVHASH; i++) {
+ kv *k;
+ for (k = mmp->kvhash[i]; k ; k = k->next) {
+
+ /*
+ * Skip unwanted entries which are either not real entries or
+ * very difficult to interpret (wildcards...) This test needs
+ * lots of improvement. Any takers?
+ */
+ key = k->key;
+ if (!key)
+ continue;
+
+ /* Skip '/defaults' */
+ if (STREQ(key, "/defaults"))
+ continue;
+
+ /* Skip '*' */
+ if (!fully_browsable && strchr(key, '*'))
+ continue;
+
+ /*
+ * If the map has a prefix-string then check if the key starts with
+ * this string, and if it does, skip over this prefix. If it has a
+ * prefix and it doesn't match the start of the key, skip it.
+ */
+ if (preflen) {
+ if (preflen > strlen(key))
+ continue;
+ if (!NSTREQ(key, mp->am_pref, preflen))
+ continue;
+ key += preflen;
+ }
+
+ /* no more '/' are allowed, unless browsable_dirs=full was used */
+ if (!fully_browsable && strchr(key, '/'))
+ continue;
+
+ /* no duplicates allowed */
+ if (key_already_in_chain(key, current_chain))
+ continue;
+
+ /* fill in a cell and link the entry */
+ if (num_entries >= max_entries) {
+ /* out of space */
+ plog(XLOG_DEBUG, "make_entry_chain: no more space in chain");
+ if (num_entries > 0) {
+ chain[num_entries - 1].ne_nextentry = 0;
+ retval = &chain[0];
+ }
+ return retval;
+ }
+
+ /* we have space. put entry in next cell */
+ ++last_cookie;
+ chain[num_entries].ne_fileid = (u_int) last_cookie;
+ *(u_int *) chain[num_entries].ne_cookie = (u_int) last_cookie;
+ chain[num_entries].ne_name = key;
+ if (num_entries < max_entries - 1) { /* link to next one */
+ chain[num_entries].ne_nextentry = &chain[num_entries + 1];
+ }
+ ++num_entries;
+ } /* end of "while (k)" */
+ } /* end of "for (i ... NKVHASH ..." */
+
+ /* terminate chain */
+ if (num_entries > 0) {
+ chain[num_entries - 1].ne_nextentry = 0;
+ retval = &chain[0];
+ }
+
+ return retval;
+}
+
+
+
+/* This one is called only if map is browsable */
+static int
+amfs_readdir_browsable(am_node *mp, nfscookie cookie, nfsdirlist *dp, nfsentry *ep, u_int count, int fully_browsable)
+{
+ u_int gen = *(u_int *) cookie;
+ int chain_length, i;
+ static nfsentry *te, *te_next;
+ static int j;
+
+ dp->dl_eof = FALSE; /* assume readdir not done */
+
+ if (amuDebug(D_READDIR))
+ plog(XLOG_DEBUG, "amfs_readdir_browsable gen=%u, count=%d",
+ gen, count);
+
+ if (gen == 0) {
+ /*
+ * In the default instance (which is used to start a search) we return
+ * "." and "..".
+ *
+ * This assumes that the count is big enough to allow both "." and ".."
+ * to be returned in a single packet. If it isn't (which would be
+ * fairly unbelievable) then tough.
+ */
+ dlog("amfs_readdir_browsable: default search");
+ /*
+ * Check for enough room. This is extremely approximate but is more
+ * than enough space. Really need 2 times:
+ * 4byte fileid
+ * 4byte cookie
+ * 4byte name length
+ * 4byte name
+ * plus the dirlist structure */
+ if (count < (2 * (2 * (sizeof(*ep) + sizeof("..") + 4) + sizeof(*dp))))
+ return EINVAL;
+
+ /*
+ * compute # of entries to send in this chain.
+ * heuristics: 128 bytes per entry.
+ * This is too much probably, but it seems to work better because
+ * of the re-entrant nature of nfs_readdir, and esp. on systems
+ * like OpenBSD 2.2.
+ */
+ chain_length = count / 128;
+
+ /* reset static state counters */
+ te = te_next = NULL;
+
+ dp->dl_entries = ep;
+
+ /* construct "." */
+ ep[0].ne_fileid = mp->am_gen;
+ ep[0].ne_name = ".";
+ ep[0].ne_nextentry = &ep[1];
+ *(u_int *) ep[0].ne_cookie = 0;
+
+ /* construct ".." */
+ if (mp->am_parent)
+ ep[1].ne_fileid = mp->am_parent->am_gen;
+ else
+ ep[1].ne_fileid = mp->am_gen;
+
+ ep[1].ne_name = "..";
+ ep[1].ne_nextentry = 0;
+ *(u_int *) ep[1].ne_cookie = DOT_DOT_COOKIE;
+
+ /*
+ * If map is browsable, call a function make_entry_chain() to construct
+ * a linked list of unmounted keys, and return it. Then link the chain
+ * to the regular list. Get the chain only once, but return
+ * chunks of it each time.
+ */
+ te = make_entry_chain(mp, dp->dl_entries, fully_browsable);
+ if (!te)
+ return 0;
+ if (amuDebug(D_READDIR)) {
+ nfsentry *ne;
+ for (j = 0, ne = te; ne; ne = ne->ne_nextentry)
+ plog(XLOG_DEBUG, "gen1 key %4d \"%s\"", j++, ne->ne_name);
+ }
+
+ /* return only "chain_length" entries */
+ te_next = te;
+ for (i=1; i<chain_length; ++i) {
+ te_next = te_next->ne_nextentry;
+ if (!te_next)
+ break;
+ }
+ if (te_next) {
+ nfsentry *te_saved = te_next->ne_nextentry;
+ te_next->ne_nextentry = NULL; /* terminate "te" chain */
+ te_next = te_saved; /* save rest of "te" for next iteration */
+ dp->dl_eof = FALSE; /* tell readdir there's more */
+ } else {
+ dp->dl_eof = TRUE; /* tell readdir that's it */
+ }
+ ep[1].ne_nextentry = te; /* append this chunk of "te" chain */
+ if (amuDebug(D_READDIR)) {
+ nfsentry *ne;
+ for (j = 0, ne = te; ne; ne = ne->ne_nextentry)
+ plog(XLOG_DEBUG, "gen2 key %4d \"%s\"", j++, ne->ne_name);
+ for (j = 0, ne = ep; ne; ne = ne->ne_nextentry)
+ plog(XLOG_DEBUG, "gen2+ key %4d \"%s\" fi=%d ck=%d",
+ j++, ne->ne_name, ne->ne_fileid, *(u_int *)ne->ne_cookie);
+ plog(XLOG_DEBUG, "EOF is %d", dp->dl_eof);
+ }
+ return 0;
+ } /* end of "if (gen == 0)" statement */
+
+ dlog("amfs_readdir_browsable: real child");
+
+ if (gen == DOT_DOT_COOKIE) {
+ dlog("amfs_readdir_browsable: End of readdir in %s", mp->am_path);
+ dp->dl_eof = TRUE;
+ dp->dl_entries = 0;
+ return 0;
+ }
+
+ /*
+ * If browsable directories, then continue serving readdir() with another
+ * chunk of entries, starting from where we left off (when gen was equal
+ * to 0). Once again, assume last chunk served to readdir.
+ */
+ dp->dl_eof = TRUE;
+ dp->dl_entries = ep;
+
+ te = te_next; /* reset 'te' from last saved te_next */
+ if (!te) { /* another indicator of end of readdir */
+ dp->dl_entries = 0;
+ return 0;
+ }
+ /*
+ * compute # of entries to send in this chain.
+ * heuristics: 128 bytes per entry.
+ */
+ chain_length = count / 128;
+
+ /* return only "chain_length" entries */
+ for (i = 1; i < chain_length; ++i) {
+ te_next = te_next->ne_nextentry;
+ if (!te_next)
+ break;
+ }
+ if (te_next) {
+ nfsentry *te_saved = te_next->ne_nextentry;
+ te_next->ne_nextentry = NULL; /* terminate "te" chain */
+ te_next = te_saved; /* save rest of "te" for next iteration */
+ dp->dl_eof = FALSE; /* tell readdir there's more */
+ }
+ ep = te; /* send next chunk of "te" chain */
+ dp->dl_entries = ep;
+ if (amuDebug(D_READDIR)) {
+ nfsentry *ne;
+ plog(XLOG_DEBUG, "dl_entries=%p, te_next=%p, dl_eof=%d",
+ dp->dl_entries, te_next, dp->dl_eof);
+ for (ne = te; ne; ne = ne->ne_nextentry)
+ plog(XLOG_DEBUG, "gen3 key %4d \"%s\"", j++, ne->ne_name);
+ }
+ return 0;
+}
+
+
+/*
+ * This readdir function which call a special version of it that allows
+ * browsing if browsable_dirs=yes was set on the map.
+ */
+int
+amfs_generic_readdir(am_node *mp, nfscookie cookie, nfsdirlist *dp, nfsentry *ep, u_int count)
+{
+ u_int gen = *(u_int *) cookie;
+ am_node *xp;
+ mntent_t mnt;
+
+ dp->dl_eof = FALSE; /* assume readdir not done */
+
+ /* check if map is browsable */
+ if (mp->am_mnt && mp->am_mnt->mf_mopts) {
+ mnt.mnt_opts = mp->am_mnt->mf_mopts;
+ if (amu_hasmntopt(&mnt, "fullybrowsable"))
+ return amfs_readdir_browsable(mp, cookie, dp, ep, count, TRUE);
+ if (amu_hasmntopt(&mnt, "browsable"))
+ return amfs_readdir_browsable(mp, cookie, dp, ep, count, FALSE);
+ }
+
+ /* when gen is 0, we start reading from the beginning of the directory */
+ if (gen == 0) {
+ /*
+ * In the default instance (which is used to start a search) we return
+ * "." and "..".
+ *
+ * This assumes that the count is big enough to allow both "." and ".."
+ * to be returned in a single packet. If it isn't (which would be
+ * fairly unbelievable) then tough.
+ */
+ dlog("amfs_generic_readdir: default search");
+ /*
+ * Check for enough room. This is extremely approximate but is more
+ * than enough space. Really need 2 times:
+ * 4byte fileid
+ * 4byte cookie
+ * 4byte name length
+ * 4byte name
+ * plus the dirlist structure */
+ if (count < (2 * (2 * (sizeof(*ep) + sizeof("..") + 4) + sizeof(*dp))))
+ return EINVAL;
+
+ xp = next_nonerror_node(mp->am_child);
+ dp->dl_entries = ep;
+
+ /* construct "." */
+ ep[0].ne_fileid = mp->am_gen;
+ ep[0].ne_name = ".";
+ ep[0].ne_nextentry = &ep[1];
+ *(u_int *) ep[0].ne_cookie = 0;
+
+ /* construct ".." */
+ if (mp->am_parent)
+ ep[1].ne_fileid = mp->am_parent->am_gen;
+ else
+ ep[1].ne_fileid = mp->am_gen;
+ ep[1].ne_name = "..";
+ ep[1].ne_nextentry = 0;
+ *(u_int *) ep[1].ne_cookie = (xp ? xp->am_gen : DOT_DOT_COOKIE);
+
+ if (!xp)
+ dp->dl_eof = TRUE; /* by default assume readdir done */
+
+ if (amuDebug(D_READDIR)) {
+ nfsentry *ne;
+ int j;
+ for (j = 0, ne = ep; ne; ne = ne->ne_nextentry)
+ plog(XLOG_DEBUG, "gen1 key %4d \"%s\" fi=%d ck=%d",
+ j++, ne->ne_name, ne->ne_fileid, *(u_int *)ne->ne_cookie);
+ }
+ return 0;
+ }
+ dlog("amfs_generic_readdir: real child");
+
+ if (gen == DOT_DOT_COOKIE) {
+ dlog("amfs_generic_readdir: End of readdir in %s", mp->am_path);
+ dp->dl_eof = TRUE;
+ dp->dl_entries = 0;
+ if (amuDebug(D_READDIR))
+ plog(XLOG_DEBUG, "end of readdir eof=TRUE, dl_entries=0\n");
+ return 0;
+ }
+
+ /* non-browsable directories code */
+ xp = mp->am_child;
+ while (xp && xp->am_gen != gen)
+ xp = xp->am_osib;
+
+ if (xp) {
+ int nbytes = count / 2; /* conservative */
+ int todo = MAX_READDIR_ENTRIES;
+
+ dp->dl_entries = ep;
+ do {
+ am_node *xp_next = next_nonerror_node(xp->am_osib);
+
+ if (xp_next) {
+ *(u_int *) ep->ne_cookie = xp_next->am_gen;
+ } else {
+ *(u_int *) ep->ne_cookie = DOT_DOT_COOKIE;
+ dp->dl_eof = TRUE;
+ }
+
+ ep->ne_fileid = xp->am_gen;
+ ep->ne_name = xp->am_name;
+ nbytes -= sizeof(*ep) + 1;
+ if (xp->am_name)
+ nbytes -= strlen(xp->am_name);
+
+ xp = xp_next;
+
+ if (nbytes > 0 && !dp->dl_eof && todo > 1) {
+ ep->ne_nextentry = ep + 1;
+ ep++;
+ --todo;
+ } else {
+ todo = 0;
+ }
+ } while (todo > 0);
+
+ ep->ne_nextentry = 0;
+
+ if (amuDebug(D_READDIR)) {
+ nfsentry *ne;
+ int j;
+ for (j=0,ne=ep; ne; ne=ne->ne_nextentry)
+ plog(XLOG_DEBUG, "gen2 key %4d \"%s\" fi=%d ck=%d",
+ j++, ne->ne_name, ne->ne_fileid, *(u_int *)ne->ne_cookie);
+ }
+ return 0;
+ }
+ return ESTALE;
+}
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