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-rw-r--r--dbm/sdbm/sdbm.c584
-rw-r--r--dbm/sdbm/sdbm_hash.c63
-rw-r--r--dbm/sdbm/sdbm_lock.c79
-rw-r--r--dbm/sdbm/sdbm_pair.c320
-rw-r--r--dbm/sdbm/sdbm_pair.h40
-rw-r--r--dbm/sdbm/sdbm_private.h84
-rw-r--r--dbm/sdbm/sdbm_tune.h40
7 files changed, 1210 insertions, 0 deletions
diff --git a/dbm/sdbm/sdbm.c b/dbm/sdbm/sdbm.c
new file mode 100644
index 0000000..a62b009
--- /dev/null
+++ b/dbm/sdbm/sdbm.c
@@ -0,0 +1,584 @@
+/* Licensed to the Apache Software Foundation (ASF) under one or more
+ * contributor license agreements. See the NOTICE file distributed with
+ * this work for additional information regarding copyright ownership.
+ * The ASF licenses this file to You under the Apache License, Version 2.0
+ * (the "License"); you may not use this file except in compliance with
+ * the License. You may obtain a copy of the License at
+ *
+ * http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+/*
+ * sdbm - ndbm work-alike hashed database library
+ * based on Per-Aake Larson's Dynamic Hashing algorithms. BIT 18 (1978).
+ * author: oz@nexus.yorku.ca
+ * ex-public domain, ported to APR for Apache 2
+ * core routines
+ */
+
+#include "apr.h"
+#include "apr_file_io.h"
+#include "apr_strings.h"
+#include "apr_errno.h"
+#include "apr_sdbm.h"
+
+#include "sdbm_tune.h"
+#include "sdbm_pair.h"
+#include "sdbm_private.h"
+
+#include <string.h> /* for memset() */
+#include <stdlib.h> /* for malloc() and free() */
+
+/*
+ * forward
+ */
+static int getdbit (apr_sdbm_t *, long);
+static apr_status_t setdbit(apr_sdbm_t *, long);
+static apr_status_t getpage(apr_sdbm_t *db, long, int, int);
+static apr_status_t getnext(apr_sdbm_datum_t *key, apr_sdbm_t *db);
+static apr_status_t makroom(apr_sdbm_t *, long, int);
+
+/*
+ * useful macros
+ */
+#define bad(x) ((x).dptr == NULL || (x).dsize <= 0)
+#define exhash(item) sdbm_hash((item).dptr, (item).dsize)
+
+#define OFF_PAG(off) (apr_off_t) (off) * PBLKSIZ
+#define OFF_DIR(off) (apr_off_t) (off) * DBLKSIZ
+
+static const long masks[] = {
+ 000000000000, 000000000001, 000000000003, 000000000007,
+ 000000000017, 000000000037, 000000000077, 000000000177,
+ 000000000377, 000000000777, 000000001777, 000000003777,
+ 000000007777, 000000017777, 000000037777, 000000077777,
+ 000000177777, 000000377777, 000000777777, 000001777777,
+ 000003777777, 000007777777, 000017777777, 000037777777,
+ 000077777777, 000177777777, 000377777777, 000777777777,
+ 001777777777, 003777777777, 007777777777, 017777777777
+};
+
+const apr_sdbm_datum_t sdbm_nullitem = { NULL, 0 };
+
+static apr_status_t database_cleanup(void *data)
+{
+ apr_sdbm_t *db = data;
+
+ /*
+ * Can't rely on apr_sdbm_unlock, since it will merely
+ * decrement the refcnt if several locks are held.
+ */
+ if (db->flags & (SDBM_SHARED_LOCK | SDBM_EXCLUSIVE_LOCK))
+ (void) apr_file_unlock(db->dirf);
+ (void) apr_file_close(db->dirf);
+ (void) apr_file_close(db->pagf);
+ free(db);
+
+ return APR_SUCCESS;
+}
+
+static apr_status_t prep(apr_sdbm_t **pdb, const char *dirname, const char *pagname,
+ apr_int32_t flags, apr_fileperms_t perms, apr_pool_t *p)
+{
+ apr_sdbm_t *db;
+ apr_status_t status;
+
+ *pdb = NULL;
+
+ db = malloc(sizeof(*db));
+ memset(db, 0, sizeof(*db));
+ db->pagbno = -1L;
+
+ db->pool = p;
+
+ /*
+ * adjust user flags so that WRONLY becomes RDWR,
+ * as required by this package. Also set our internal
+ * flag for RDONLY if needed.
+ */
+ if (!(flags & APR_FOPEN_WRITE)) {
+ db->flags |= SDBM_RDONLY;
+ }
+
+ /*
+ * adjust the file open flags so that we handle locking
+ * on our own (don't rely on any locking behavior within
+ * an apr_file_t, in case it's ever introduced, and set
+ * our own flag.
+ */
+ if (flags & APR_FOPEN_SHARELOCK) {
+ db->flags |= SDBM_SHARED;
+ flags &= ~APR_FOPEN_SHARELOCK;
+ }
+
+ flags |= APR_FOPEN_BINARY | APR_FOPEN_READ;
+
+ /*
+ * open the files in sequence, and stat the dirfile.
+ * If we fail anywhere, undo everything, return NULL.
+ */
+
+ if ((status = apr_file_open(&db->dirf, dirname, flags, perms, p))
+ != APR_SUCCESS)
+ goto error;
+
+ if ((status = apr_file_open(&db->pagf, pagname, flags, perms, p))
+ != APR_SUCCESS)
+ goto error;
+
+ if ((status = apr_sdbm_lock(db, (db->flags & SDBM_RDONLY)
+ ? APR_FLOCK_SHARED
+ : APR_FLOCK_EXCLUSIVE))
+ != APR_SUCCESS)
+ goto error;
+
+ /* apr_pcalloc zeroed the buffers
+ * apr_sdbm_lock stated the dirf->size and invalidated the cache
+ */
+
+ /*
+ * if we are opened in SHARED mode, unlock ourself
+ */
+ if (db->flags & SDBM_SHARED)
+ if ((status = apr_sdbm_unlock(db)) != APR_SUCCESS)
+ goto error;
+
+ /* make sure that we close the database at some point */
+ apr_pool_cleanup_register(p, db, database_cleanup, apr_pool_cleanup_null);
+
+ /* Done! */
+ *pdb = db;
+ return APR_SUCCESS;
+
+error:
+ if (db->dirf && db->pagf)
+ (void) apr_sdbm_unlock(db);
+ if (db->dirf != NULL)
+ (void) apr_file_close(db->dirf);
+ if (db->pagf != NULL) {
+ (void) apr_file_close(db->pagf);
+ }
+ free(db);
+ return status;
+}
+
+APU_DECLARE(apr_status_t) apr_sdbm_open(apr_sdbm_t **db, const char *file,
+ apr_int32_t flags,
+ apr_fileperms_t perms, apr_pool_t *p)
+{
+ char *dirname = apr_pstrcat(p, file, APR_SDBM_DIRFEXT, NULL);
+ char *pagname = apr_pstrcat(p, file, APR_SDBM_PAGFEXT, NULL);
+
+ return prep(db, dirname, pagname, flags, perms, p);
+}
+
+APU_DECLARE(apr_status_t) apr_sdbm_close(apr_sdbm_t *db)
+{
+ return apr_pool_cleanup_run(db->pool, db, database_cleanup);
+}
+
+APU_DECLARE(apr_status_t) apr_sdbm_fetch(apr_sdbm_t *db, apr_sdbm_datum_t *val,
+ apr_sdbm_datum_t key)
+{
+ apr_status_t status;
+
+ if (db == NULL || bad(key))
+ return APR_EINVAL;
+
+ if ((status = apr_sdbm_lock(db, APR_FLOCK_SHARED)) != APR_SUCCESS)
+ return status;
+
+ if ((status = getpage(db, exhash(key), 0, 1)) == APR_SUCCESS) {
+ *val = getpair(db->pagbuf, key);
+ /* ### do we want a not-found result? */
+ }
+
+ (void) apr_sdbm_unlock(db);
+
+ return status;
+}
+
+static apr_status_t write_page(apr_sdbm_t *db, const char *buf, long pagno)
+{
+ apr_status_t status;
+ apr_off_t off = OFF_PAG(pagno);
+
+ if ((status = apr_file_seek(db->pagf, APR_SET, &off)) == APR_SUCCESS)
+ status = apr_file_write_full(db->pagf, buf, PBLKSIZ, NULL);
+
+ return status;
+}
+
+APU_DECLARE(apr_status_t) apr_sdbm_delete(apr_sdbm_t *db,
+ const apr_sdbm_datum_t key)
+{
+ apr_status_t status;
+
+ if (db == NULL || bad(key))
+ return APR_EINVAL;
+ if (apr_sdbm_rdonly(db))
+ return APR_EINVAL;
+
+ if ((status = apr_sdbm_lock(db, APR_FLOCK_EXCLUSIVE)) != APR_SUCCESS)
+ return status;
+
+ if ((status = getpage(db, exhash(key), 0, 1)) == APR_SUCCESS) {
+ if (!delpair(db->pagbuf, key))
+ /* ### should we define some APRUTIL codes? */
+ status = APR_EGENERAL;
+ else
+ status = write_page(db, db->pagbuf, db->pagbno);
+ }
+
+ (void) apr_sdbm_unlock(db);
+
+ return status;
+}
+
+APU_DECLARE(apr_status_t) apr_sdbm_store(apr_sdbm_t *db, apr_sdbm_datum_t key,
+ apr_sdbm_datum_t val, int flags)
+{
+ int need;
+ register long hash;
+ apr_status_t status;
+
+ if (db == NULL || bad(key))
+ return APR_EINVAL;
+ if (apr_sdbm_rdonly(db))
+ return APR_EINVAL;
+ need = key.dsize + val.dsize;
+ /*
+ * is the pair too big (or too small) for this database ??
+ */
+ if (need < 0 || need > PAIRMAX)
+ return APR_EINVAL;
+
+ if ((status = apr_sdbm_lock(db, APR_FLOCK_EXCLUSIVE)) != APR_SUCCESS)
+ return status;
+
+ if ((status = getpage(db, (hash = exhash(key)), 0, 1)) == APR_SUCCESS) {
+
+ /*
+ * if we need to replace, delete the key/data pair
+ * first. If it is not there, ignore.
+ */
+ if (flags == APR_SDBM_REPLACE)
+ (void) delpair(db->pagbuf, key);
+ else if (!(flags & APR_SDBM_INSERTDUP) && duppair(db->pagbuf, key)) {
+ status = APR_EEXIST;
+ goto error;
+ }
+ /*
+ * if we do not have enough room, we have to split.
+ */
+ if (!fitpair(db->pagbuf, need))
+ if ((status = makroom(db, hash, need)) != APR_SUCCESS)
+ goto error;
+ /*
+ * we have enough room or split is successful. insert the key,
+ * and update the page file.
+ */
+ (void) putpair(db->pagbuf, key, val);
+
+ status = write_page(db, db->pagbuf, db->pagbno);
+ }
+
+error:
+ (void) apr_sdbm_unlock(db);
+
+ return status;
+}
+
+/*
+ * makroom - make room by splitting the overfull page
+ * this routine will attempt to make room for SPLTMAX times before
+ * giving up.
+ */
+static apr_status_t makroom(apr_sdbm_t *db, long hash, int need)
+{
+ long newp;
+ char twin[PBLKSIZ];
+ char *pag = db->pagbuf;
+ char *new = twin;
+ register int smax = SPLTMAX;
+ apr_status_t status;
+
+ do {
+ /*
+ * split the current page
+ */
+ (void) splpage(pag, new, db->hmask + 1);
+ /*
+ * address of the new page
+ */
+ newp = (hash & db->hmask) | (db->hmask + 1);
+
+ /*
+ * write delay, read avoidence/cache shuffle:
+ * select the page for incoming pair: if key is to go to the new page,
+ * write out the previous one, and copy the new one over, thus making
+ * it the current page. If not, simply write the new page, and we are
+ * still looking at the page of interest. current page is not updated
+ * here, as sdbm_store will do so, after it inserts the incoming pair.
+ */
+ if (hash & (db->hmask + 1)) {
+ if ((status = write_page(db, db->pagbuf, db->pagbno))
+ != APR_SUCCESS)
+ return status;
+
+ db->pagbno = newp;
+ (void) memcpy(pag, new, PBLKSIZ);
+ }
+ else {
+ if ((status = write_page(db, new, newp)) != APR_SUCCESS)
+ return status;
+ }
+
+ if ((status = setdbit(db, db->curbit)) != APR_SUCCESS)
+ return status;
+ /*
+ * see if we have enough room now
+ */
+ if (fitpair(pag, need))
+ return APR_SUCCESS;
+ /*
+ * try again... update curbit and hmask as getpage would have
+ * done. because of our update of the current page, we do not
+ * need to read in anything. BUT we have to write the current
+ * [deferred] page out, as the window of failure is too great.
+ */
+ db->curbit = 2 * db->curbit
+ + ((hash & (db->hmask + 1)) ? 2 : 1);
+ db->hmask |= db->hmask + 1;
+
+ if ((status = write_page(db, db->pagbuf, db->pagbno))
+ != APR_SUCCESS)
+ return status;
+
+ } while (--smax);
+
+ /*
+ * if we are here, this is real bad news. After SPLTMAX splits,
+ * we still cannot fit the key. say goodnight.
+ */
+#if 0
+ (void) write(2, "sdbm: cannot insert after SPLTMAX attempts.\n", 44);
+#endif
+ /* ### ENOSPC not really appropriate but better than nothing */
+ return APR_ENOSPC;
+
+}
+
+/* Reads 'len' bytes from file 'f' at offset 'off' into buf.
+ * 'off' is given relative to the start of the file.
+ * If 'create' is asked and EOF is returned while reading, this is taken
+ * as success (i.e. a cleared buffer is returned).
+ */
+static apr_status_t read_from(apr_file_t *f, void *buf,
+ apr_off_t off, apr_size_t len,
+ int create)
+{
+ apr_status_t status;
+
+ if ((status = apr_file_seek(f, APR_SET, &off)) != APR_SUCCESS ||
+ ((status = apr_file_read_full(f, buf, len, NULL)) != APR_SUCCESS)) {
+ /* if EOF is reached, pretend we read all zero's */
+ if (status == APR_EOF && create) {
+ memset(buf, 0, len);
+ status = APR_SUCCESS;
+ }
+ }
+
+ return status;
+}
+
+/*
+ * the following two routines will break if
+ * deletions aren't taken into account. (ndbm bug)
+ */
+APU_DECLARE(apr_status_t) apr_sdbm_firstkey(apr_sdbm_t *db,
+ apr_sdbm_datum_t *key)
+{
+ apr_status_t status;
+
+ if ((status = apr_sdbm_lock(db, APR_FLOCK_SHARED)) != APR_SUCCESS)
+ return status;
+
+ /*
+ * start at page 0
+ */
+ if ((status = getpage(db, 0, 1, 1)) == APR_SUCCESS) {
+ db->blkptr = 0;
+ db->keyptr = 0;
+ status = getnext(key, db);
+ }
+
+ (void) apr_sdbm_unlock(db);
+
+ return status;
+}
+
+APU_DECLARE(apr_status_t) apr_sdbm_nextkey(apr_sdbm_t *db,
+ apr_sdbm_datum_t *key)
+{
+ apr_status_t status;
+
+ if ((status = apr_sdbm_lock(db, APR_FLOCK_SHARED)) != APR_SUCCESS)
+ return status;
+
+ status = getnext(key, db);
+
+ (void) apr_sdbm_unlock(db);
+
+ return status;
+}
+
+/*
+ * all important binary tree traversal
+ */
+static apr_status_t getpage(apr_sdbm_t *db, long hash, int by_num, int create)
+{
+ apr_status_t status;
+ register long pagb;
+
+ if (by_num) {
+ pagb = hash;
+ }
+ else {
+ register int hbit = 0;
+ register long dbit = 0;
+
+ while (dbit < db->maxbno && getdbit(db, dbit))
+ dbit = 2 * dbit + ((hash & (1 << hbit++)) ? 2 : 1);
+ debug(("dbit: %d...", dbit));
+
+ db->curbit = dbit;
+ db->hmask = masks[hbit];
+
+ pagb = hash & db->hmask;
+ }
+
+ /*
+ * see if the block we need is already in memory.
+ * note: this lookaside cache has about 10% hit rate.
+ */
+ if (pagb != db->pagbno) {
+ /*
+ * note: here, we assume a "hole" is read as 0s.
+ * if not, must zero pagbuf first.
+ * ### joe: this assumption was surely never correct? but
+ * ### we make it so in read_from anyway.
+ */
+ if ((status = read_from(db->pagf, db->pagbuf,
+ OFF_PAG(pagb), PBLKSIZ,
+ create)) != APR_SUCCESS)
+ return status;
+
+ if (!chkpage(db->pagbuf))
+ return APR_ENOSPC; /* ### better error? */
+
+ db->pagbno = pagb;
+
+ debug(("pag read: %d\n", pagb));
+ }
+ return APR_SUCCESS;
+}
+
+static int getdbit(apr_sdbm_t *db, long dbit)
+{
+ register long c;
+ register long dirb;
+
+ c = dbit / BYTESIZ;
+ dirb = c / DBLKSIZ;
+
+ if (dirb != db->dirbno) {
+ if (read_from(db->dirf, db->dirbuf,
+ OFF_DIR(dirb), DBLKSIZ,
+ 1) != APR_SUCCESS)
+ return 0;
+
+ db->dirbno = dirb;
+
+ debug(("dir read: %d\n", dirb));
+ }
+
+ return db->dirbuf[c % DBLKSIZ] & (1 << dbit % BYTESIZ);
+}
+
+static apr_status_t setdbit(apr_sdbm_t *db, long dbit)
+{
+ register long c;
+ register long dirb;
+ apr_status_t status;
+ apr_off_t off;
+
+ c = dbit / BYTESIZ;
+ dirb = c / DBLKSIZ;
+
+ if (dirb != db->dirbno) {
+ if ((status = read_from(db->dirf, db->dirbuf,
+ OFF_DIR(dirb), DBLKSIZ,
+ 1)) != APR_SUCCESS)
+ return status;
+
+ db->dirbno = dirb;
+
+ debug(("dir read: %d\n", dirb));
+ }
+
+ db->dirbuf[c % DBLKSIZ] |= (1 << dbit % BYTESIZ);
+
+ if (dbit >= db->maxbno)
+ db->maxbno += DBLKSIZ * BYTESIZ;
+
+ off = OFF_DIR(dirb);
+ if ((status = apr_file_seek(db->dirf, APR_SET, &off)) == APR_SUCCESS)
+ status = apr_file_write_full(db->dirf, db->dirbuf, DBLKSIZ, NULL);
+
+ return status;
+}
+
+/*
+* getnext - get the next key in the page, and if done with
+* the page, try the next page in sequence
+*/
+static apr_status_t getnext(apr_sdbm_datum_t *key, apr_sdbm_t *db)
+{
+ apr_status_t status;
+ for (;;) {
+ db->keyptr++;
+ *key = getnkey(db->pagbuf, db->keyptr);
+ if (key->dptr != NULL)
+ return APR_SUCCESS;
+ /*
+ * we either run out, or there is nothing on this page..
+ * try the next one... If we lost our position on the
+ * file, we will have to seek.
+ */
+ db->blkptr++;
+ db->keyptr = 0;
+
+ /* ### EOF acceptable here too? */
+ if ((status = getpage(db, db->blkptr, 1, 0)) != APR_SUCCESS)
+ return status;
+ }
+
+ /* NOTREACHED */
+}
+
+
+APU_DECLARE(int) apr_sdbm_rdonly(apr_sdbm_t *db)
+{
+ /* ### Should we return true if the first lock is a share lock,
+ * to reflect that apr_sdbm_store and apr_sdbm_delete will fail?
+ */
+ return (db->flags & SDBM_RDONLY) != 0;
+}
+
diff --git a/dbm/sdbm/sdbm_hash.c b/dbm/sdbm/sdbm_hash.c
new file mode 100644
index 0000000..e4d7517
--- /dev/null
+++ b/dbm/sdbm/sdbm_hash.c
@@ -0,0 +1,63 @@
+/* Licensed to the Apache Software Foundation (ASF) under one or more
+ * contributor license agreements. See the NOTICE file distributed with
+ * this work for additional information regarding copyright ownership.
+ * The ASF licenses this file to You under the Apache License, Version 2.0
+ * (the "License"); you may not use this file except in compliance with
+ * the License. You may obtain a copy of the License at
+ *
+ * http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+/*
+ * sdbm - ndbm work-alike hashed database library
+ * based on Per-Aake Larson's Dynamic Hashing algorithms. BIT 18 (1978).
+ * author: oz@nexus.yorku.ca
+ * status: ex-public domain. keep it that way.
+ *
+ * hashing routine
+ */
+
+#include "apr_sdbm.h"
+#include "sdbm_private.h"
+
+/*
+ * polynomial conversion ignoring overflows
+ * [this seems to work remarkably well, in fact better
+ * then the ndbm hash function. Replace at your own risk]
+ * use: 65599 nice.
+ * 65587 even better.
+ */
+long sdbm_hash(const char *str, int len)
+{
+ register unsigned long n = 0;
+
+#define DUFF /* go ahead and use the loop-unrolled version */
+#ifdef DUFF
+
+#define HASHC n = *str++ + 65599 * n
+
+ if (len > 0) {
+ register int loop = (len + 8 - 1) >> 3;
+
+ switch(len & (8 - 1)) {
+ case 0: do {
+ HASHC; case 7: HASHC;
+ case 6: HASHC; case 5: HASHC;
+ case 4: HASHC; case 3: HASHC;
+ case 2: HASHC; case 1: HASHC;
+ } while (--loop);
+ }
+
+ }
+#else
+ while (len--)
+ n = *str++ + 65599 * n;
+#endif
+ return n;
+}
diff --git a/dbm/sdbm/sdbm_lock.c b/dbm/sdbm/sdbm_lock.c
new file mode 100644
index 0000000..7d62ffd
--- /dev/null
+++ b/dbm/sdbm/sdbm_lock.c
@@ -0,0 +1,79 @@
+/* Licensed to the Apache Software Foundation (ASF) under one or more
+ * contributor license agreements. See the NOTICE file distributed with
+ * this work for additional information regarding copyright ownership.
+ * The ASF licenses this file to You under the Apache License, Version 2.0
+ * (the "License"); you may not use this file except in compliance with
+ * the License. You may obtain a copy of the License at
+ *
+ * http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+#include "apr_file_info.h"
+#include "apr_file_io.h"
+#include "apr_sdbm.h"
+
+#include "sdbm_private.h"
+#include "sdbm_tune.h"
+
+/* NOTE: this function may block until it acquires the lock */
+APU_DECLARE(apr_status_t) apr_sdbm_lock(apr_sdbm_t *db, int type)
+{
+ apr_status_t status;
+ int lock_type = type & APR_FLOCK_TYPEMASK;
+
+ if (!(lock_type == APR_FLOCK_SHARED || lock_type == APR_FLOCK_EXCLUSIVE))
+ return APR_EINVAL;
+
+ if (db->flags & SDBM_EXCLUSIVE_LOCK) {
+ ++db->lckcnt;
+ return APR_SUCCESS;
+ }
+ else if (db->flags & SDBM_SHARED_LOCK) {
+ /*
+ * Cannot promote a shared lock to an exlusive lock
+ * in a cross-platform compatibile manner.
+ */
+ if (type == APR_FLOCK_EXCLUSIVE)
+ return APR_EINVAL;
+ ++db->lckcnt;
+ return APR_SUCCESS;
+ }
+ /*
+ * zero size: either a fresh database, or one with a single,
+ * unsplit data page: dirpage is all zeros.
+ */
+ if ((status = apr_file_lock(db->dirf, type)) == APR_SUCCESS)
+ {
+ apr_finfo_t finfo;
+ if ((status = apr_file_info_get(&finfo, APR_FINFO_SIZE, db->dirf))
+ != APR_SUCCESS) {
+ (void) apr_file_unlock(db->dirf);
+ return status;
+ }
+
+ SDBM_INVALIDATE_CACHE(db, finfo);
+
+ ++db->lckcnt;
+ if (type == APR_FLOCK_SHARED)
+ db->flags |= SDBM_SHARED_LOCK;
+ else if (type == APR_FLOCK_EXCLUSIVE)
+ db->flags |= SDBM_EXCLUSIVE_LOCK;
+ }
+ return status;
+}
+
+APU_DECLARE(apr_status_t) apr_sdbm_unlock(apr_sdbm_t *db)
+{
+ if (!(db->flags & (SDBM_SHARED_LOCK | SDBM_EXCLUSIVE_LOCK)))
+ return APR_EINVAL;
+ if (--db->lckcnt > 0)
+ return APR_SUCCESS;
+ db->flags &= ~(SDBM_SHARED_LOCK | SDBM_EXCLUSIVE_LOCK);
+ return apr_file_unlock(db->dirf);
+}
diff --git a/dbm/sdbm/sdbm_pair.c b/dbm/sdbm/sdbm_pair.c
new file mode 100644
index 0000000..50d7965
--- /dev/null
+++ b/dbm/sdbm/sdbm_pair.c
@@ -0,0 +1,320 @@
+/* Licensed to the Apache Software Foundation (ASF) under one or more
+ * contributor license agreements. See the NOTICE file distributed with
+ * this work for additional information regarding copyright ownership.
+ * The ASF licenses this file to You under the Apache License, Version 2.0
+ * (the "License"); you may not use this file except in compliance with
+ * the License. You may obtain a copy of the License at
+ *
+ * http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+/*
+ * sdbm - ndbm work-alike hashed database library
+ * based on Per-Aake Larson's Dynamic Hashing algorithms. BIT 18 (1978).
+ * author: oz@nexus.yorku.ca
+ * status: ex-public domain.
+ *
+ * page-level routines
+ */
+
+#include "apr_sdbm.h"
+
+#include "sdbm_tune.h"
+#include "sdbm_pair.h"
+#include "sdbm_private.h"
+
+#include <string.h> /* for memset() */
+
+
+#define exhash(item) sdbm_hash((item).dptr, (item).dsize)
+
+/*
+ * forward
+ */
+static int seepair(char *, int, char *, int);
+
+/*
+ * page format:
+ * +------------------------------+
+ * ino | n | keyoff | datoff | keyoff |
+ * +------------+--------+--------+
+ * | datoff | - - - ----> |
+ * +--------+---------------------+
+ * | F R E E A R E A |
+ * +--------------+---------------+
+ * | <---- - - - | data |
+ * +--------+-----+----+----------+
+ * | key | data | key |
+ * +--------+----------+----------+
+ *
+ * calculating the offsets for free area: if the number
+ * of entries (ino[0]) is zero, the offset to the END of
+ * the free area is the block size. Otherwise, it is the
+ * nth (ino[ino[0]]) entry's offset.
+ */
+
+int
+fitpair(pag, need)
+char *pag;
+int need;
+{
+ register int n;
+ register int off;
+ register int avail;
+ register short *ino = (short *) pag;
+
+ off = ((n = ino[0]) > 0) ? ino[n] : PBLKSIZ;
+ avail = off - (n + 1) * sizeof(short);
+ need += 2 * sizeof(short);
+
+ debug(("avail %d need %d\n", avail, need));
+
+ return need <= avail;
+}
+
+void
+putpair(pag, key, val)
+char *pag;
+apr_sdbm_datum_t key;
+apr_sdbm_datum_t val;
+{
+ register int n;
+ register int off;
+ register short *ino = (short *) pag;
+
+ off = ((n = ino[0]) > 0) ? ino[n] : PBLKSIZ;
+/*
+ * enter the key first
+ */
+ off -= key.dsize;
+ (void) memcpy(pag + off, key.dptr, key.dsize);
+ ino[n + 1] = off;
+/*
+ * now the data
+ */
+ off -= val.dsize;
+ (void) memcpy(pag + off, val.dptr, val.dsize);
+ ino[n + 2] = off;
+/*
+ * adjust item count
+ */
+ ino[0] += 2;
+}
+
+apr_sdbm_datum_t
+getpair(pag, key)
+char *pag;
+apr_sdbm_datum_t key;
+{
+ register int i;
+ register int n;
+ apr_sdbm_datum_t val;
+ register short *ino = (short *) pag;
+
+ if ((n = ino[0]) == 0)
+ return sdbm_nullitem;
+
+ if ((i = seepair(pag, n, key.dptr, key.dsize)) == 0)
+ return sdbm_nullitem;
+
+ val.dptr = pag + ino[i + 1];
+ val.dsize = ino[i] - ino[i + 1];
+ return val;
+}
+
+int
+duppair(pag, key)
+char *pag;
+apr_sdbm_datum_t key;
+{
+ register short *ino = (short *) pag;
+ return ino[0] > 0 && seepair(pag, ino[0], key.dptr, key.dsize) > 0;
+}
+
+apr_sdbm_datum_t
+getnkey(pag, num)
+char *pag;
+int num;
+{
+ apr_sdbm_datum_t key;
+ register int off;
+ register short *ino = (short *) pag;
+
+ num = num * 2 - 1;
+ if (ino[0] == 0 || num > ino[0])
+ return sdbm_nullitem;
+
+ off = (num > 1) ? ino[num - 1] : PBLKSIZ;
+
+ key.dptr = pag + ino[num];
+ key.dsize = off - ino[num];
+
+ return key;
+}
+
+int
+delpair(pag, key)
+char *pag;
+apr_sdbm_datum_t key;
+{
+ register int n;
+ register int i;
+ register short *ino = (short *) pag;
+
+ if ((n = ino[0]) == 0)
+ return 0;
+
+ if ((i = seepair(pag, n, key.dptr, key.dsize)) == 0)
+ return 0;
+/*
+ * found the key. if it is the last entry
+ * [i.e. i == n - 1] we just adjust the entry count.
+ * hard case: move all data down onto the deleted pair,
+ * shift offsets onto deleted offsets, and adjust them.
+ * [note: 0 < i < n]
+ */
+ if (i < n - 1) {
+ register int m;
+ register char *dst = pag + (i == 1 ? PBLKSIZ : ino[i - 1]);
+ register char *src = pag + ino[i + 1];
+ register short zoo = (short) (dst - src);
+
+ debug(("free-up %d ", zoo));
+/*
+ * shift data/keys down
+ */
+ m = ino[i + 1] - ino[n];
+
+#undef DUFF /* just use memmove. it should be plenty fast. */
+#ifdef DUFF
+#define MOVB *--dst = *--src
+
+ if (m > 0) {
+ register int loop = (m + 8 - 1) >> 3;
+
+ switch (m & (8 - 1)) {
+ case 0: do {
+ MOVB; case 7: MOVB;
+ case 6: MOVB; case 5: MOVB;
+ case 4: MOVB; case 3: MOVB;
+ case 2: MOVB; case 1: MOVB;
+ } while (--loop);
+ }
+ }
+#else
+ dst -= m;
+ src -= m;
+ memmove(dst, src, m);
+#endif
+
+/*
+ * adjust offset index up
+ */
+ while (i < n - 1) {
+ ino[i] = ino[i + 2] + zoo;
+ i++;
+ }
+ }
+ ino[0] -= 2;
+ return 1;
+}
+
+/*
+ * search for the key in the page.
+ * return offset index in the range 0 < i < n.
+ * return 0 if not found.
+ */
+static int
+seepair(pag, n, key, siz)
+char *pag;
+register int n;
+register char *key;
+register int siz;
+{
+ register int i;
+ register int off = PBLKSIZ;
+ register short *ino = (short *) pag;
+
+ for (i = 1; i < n; i += 2) {
+ if (siz == off - ino[i] &&
+ memcmp(key, pag + ino[i], siz) == 0)
+ return i;
+ off = ino[i + 1];
+ }
+ return 0;
+}
+
+void
+splpage(pag, new, sbit)
+char *pag;
+char *new;
+long sbit;
+{
+ apr_sdbm_datum_t key;
+ apr_sdbm_datum_t val;
+
+ register int n;
+ register int off = PBLKSIZ;
+ char cur[PBLKSIZ];
+ register short *ino = (short *) cur;
+
+ (void) memcpy(cur, pag, PBLKSIZ);
+ (void) memset(pag, 0, PBLKSIZ);
+ (void) memset(new, 0, PBLKSIZ);
+
+ n = ino[0];
+ for (ino++; n > 0; ino += 2) {
+ key.dptr = cur + ino[0];
+ key.dsize = off - ino[0];
+ val.dptr = cur + ino[1];
+ val.dsize = ino[0] - ino[1];
+/*
+ * select the page pointer (by looking at sbit) and insert
+ */
+ (void) putpair((exhash(key) & sbit) ? new : pag, key, val);
+
+ off = ino[1];
+ n -= 2;
+ }
+
+ debug(("%d split %d/%d\n", ((short *) cur)[0] / 2,
+ ((short *) new)[0] / 2,
+ ((short *) pag)[0] / 2));
+}
+
+/*
+ * check page sanity:
+ * number of entries should be something
+ * reasonable, and all offsets in the index should be in order.
+ * this could be made more rigorous.
+ */
+int
+chkpage(pag)
+char *pag;
+{
+ register int n;
+ register int off;
+ register short *ino = (short *) pag;
+
+ if ((n = ino[0]) < 0 || n > PBLKSIZ / sizeof(short))
+ return 0;
+
+ if (n > 0) {
+ off = PBLKSIZ;
+ for (ino++; n > 0; ino += 2) {
+ if (ino[0] < 0 || ino[0] > off ||
+ ino[1] < 0 || ino[1] > off ||
+ ino[1] > ino[0])
+ return 0;
+ off = ino[1];
+ n -= 2;
+ }
+ }
+ return 1;
+}
diff --git a/dbm/sdbm/sdbm_pair.h b/dbm/sdbm/sdbm_pair.h
new file mode 100644
index 0000000..222c5e1
--- /dev/null
+++ b/dbm/sdbm/sdbm_pair.h
@@ -0,0 +1,40 @@
+/* Licensed to the Apache Software Foundation (ASF) under one or more
+ * contributor license agreements. See the NOTICE file distributed with
+ * this work for additional information regarding copyright ownership.
+ * The ASF licenses this file to You under the Apache License, Version 2.0
+ * (the "License"); you may not use this file except in compliance with
+ * the License. You may obtain a copy of the License at
+ *
+ * http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+#ifndef SDBM_PAIR_H
+#define SDBM_PAIR_H
+
+/* Mini EMBED (pair.c) */
+#define chkpage apu__sdbm_chkpage
+#define delpair apu__sdbm_delpair
+#define duppair apu__sdbm_duppair
+#define fitpair apu__sdbm_fitpair
+#define getnkey apu__sdbm_getnkey
+#define getpair apu__sdbm_getpair
+#define putpair apu__sdbm_putpair
+#define splpage apu__sdbm_splpage
+
+int fitpair(char *, int);
+void putpair(char *, apr_sdbm_datum_t, apr_sdbm_datum_t);
+apr_sdbm_datum_t getpair(char *, apr_sdbm_datum_t);
+int delpair(char *, apr_sdbm_datum_t);
+int chkpage (char *);
+apr_sdbm_datum_t getnkey(char *, int);
+void splpage(char *, char *, long);
+int duppair(char *, apr_sdbm_datum_t);
+
+#endif /* SDBM_PAIR_H */
+
diff --git a/dbm/sdbm/sdbm_private.h b/dbm/sdbm/sdbm_private.h
new file mode 100644
index 0000000..f5d1ae0
--- /dev/null
+++ b/dbm/sdbm/sdbm_private.h
@@ -0,0 +1,84 @@
+/* Licensed to the Apache Software Foundation (ASF) under one or more
+ * contributor license agreements. See the NOTICE file distributed with
+ * this work for additional information regarding copyright ownership.
+ * The ASF licenses this file to You under the Apache License, Version 2.0
+ * (the "License"); you may not use this file except in compliance with
+ * the License. You may obtain a copy of the License at
+ *
+ * http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+/*
+ * sdbm - ndbm work-alike hashed database library
+ * based on Per-Ake Larson's Dynamic Hashing algorithms. BIT 18 (1978).
+ * author: oz@nexus.yorku.ca
+ */
+
+#ifndef SDBM_PRIVATE_H
+#define SDBM_PRIVATE_H
+
+#include "apr.h"
+#include "apr_pools.h"
+#include "apr_file_io.h"
+#include "apr_errno.h" /* for apr_status_t */
+
+#if 0
+/* if the block/page size is increased, it breaks perl apr_sdbm_t compatibility */
+#define DBLKSIZ 16384
+#define PBLKSIZ 8192
+#define PAIRMAX 8008 /* arbitrary on PBLKSIZ-N */
+#else
+#define DBLKSIZ 4096
+#define PBLKSIZ 1024
+#define PAIRMAX 1008 /* arbitrary on PBLKSIZ-N */
+#endif
+#define SPLTMAX 10 /* maximum allowed splits */
+
+/* for apr_sdbm_t.flags */
+#define SDBM_RDONLY 0x1 /* data base open read-only */
+#define SDBM_SHARED 0x2 /* data base open for sharing */
+#define SDBM_SHARED_LOCK 0x4 /* data base locked for shared read */
+#define SDBM_EXCLUSIVE_LOCK 0x8 /* data base locked for write */
+
+struct apr_sdbm_t {
+ apr_pool_t *pool;
+ apr_file_t *dirf; /* directory file descriptor */
+ apr_file_t *pagf; /* page file descriptor */
+ apr_int32_t flags; /* status/error flags, see below */
+ long maxbno; /* size of dirfile in bits */
+ long curbit; /* current bit number */
+ long hmask; /* current hash mask */
+ long blkptr; /* current block for nextkey */
+ int keyptr; /* current key for nextkey */
+ long blkno; /* current page to read/write */
+ long pagbno; /* current page in pagbuf */
+ char pagbuf[PBLKSIZ]; /* page file block buffer */
+ long dirbno; /* current block in dirbuf */
+ char dirbuf[DBLKSIZ]; /* directory file block buffer */
+ int lckcnt; /* number of calls to sdbm_lock */
+};
+
+
+#define sdbm_hash apu__sdbm_hash
+#define sdbm_nullitem apu__sdbm_nullitem
+
+extern const apr_sdbm_datum_t sdbm_nullitem;
+
+long sdbm_hash(const char *str, int len);
+
+/*
+ * zero the cache
+ */
+#define SDBM_INVALIDATE_CACHE(db, finfo) \
+ do { db->dirbno = (!finfo.size) ? 0 : -1; \
+ db->pagbno = -1; \
+ db->maxbno = (long)(finfo.size * BYTESIZ); \
+ } while (0);
+
+#endif /* SDBM_PRIVATE_H */
diff --git a/dbm/sdbm/sdbm_tune.h b/dbm/sdbm/sdbm_tune.h
new file mode 100644
index 0000000..9bf3d09
--- /dev/null
+++ b/dbm/sdbm/sdbm_tune.h
@@ -0,0 +1,40 @@
+/* Licensed to the Apache Software Foundation (ASF) under one or more
+ * contributor license agreements. See the NOTICE file distributed with
+ * this work for additional information regarding copyright ownership.
+ * The ASF licenses this file to You under the Apache License, Version 2.0
+ * (the "License"); you may not use this file except in compliance with
+ * the License. You may obtain a copy of the License at
+ *
+ * http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+/*
+ * sdbm - ndbm work-alike hashed database library
+ * tuning and portability constructs [not nearly enough]
+ * author: oz@nexus.yorku.ca
+ */
+
+#ifndef SDBM_TUNE_H
+#define SDBM_TUNE_H
+
+#include "apr_errno.h"
+
+/* ### this might be better off as sizeof(char *) */
+#define BYTESIZ 8
+
+/*
+ * misc
+ */
+#ifdef DEBUG
+#define debug(x) printf x
+#else
+#define debug(x)
+#endif
+
+#endif /* SDBM_TUNE_H */
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