Start the oft-discussed, but oft-punted lib/aputil library. Drop in a first

cut at an "any" DBM set of cover functions.


git-svn-id: http://svn.apache.org/repos/asf/apr/apr-util/trunk@57925 13f79535-47bb-0310-9956-ffa450edef68

1 files changed, 300 insertions, 0 deletions

diff --git a/dbm/apr_dbm.c b/dbm/apr_dbm.c
new file mode 100644
index 00000000..52caea7b
--- /dev/null
+++ b/dbm/apr_dbm.c
@@ -0,0 +1,300 @@
+/* ====================================================================
+ * The Apache Software License, Version 1.1
+ *
+ * Copyright (c) 2000 The Apache Software Foundation.  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. The end-user documentation included with the redistribution,
+ *    if any, must include the following acknowledgment:
+ *       "This product includes software developed by the
+ *        Apache Software Foundation (http://www.apache.org/)."
+ *    Alternately, this acknowledgment may appear in the software itself,
+ *    if and wherever such third-party acknowledgments normally appear.
+ *
+ * 4. The names "Apache" and "Apache Software Foundation" must
+ *    not be used to endorse or promote products derived from this
+ *    software without prior written permission. For written
+ *    permission, please contact apache@apache.org.
+ *
+ * 5. Products derived from this software may not be called "Apache",
+ *    nor may "Apache" appear in their name, without prior written
+ *    permission of the Apache Software Foundation.
+ *
+ * THIS SOFTWARE IS PROVIDED ``AS IS'' AND ANY EXPRESSED 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 APACHE SOFTWARE FOUNDATION OR
+ * ITS 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.
+ * ====================================================================
+ *
+ * This software consists of voluntary contributions made by many
+ * individuals on behalf of the Apache Software Foundation.  For more
+ * information on the Apache Software Foundation, please see
+ * <http://www.apache.org/>.
+ */
+
+#include "apr.h"
+#include "apr_errno.h"
+#include "apr_pools.h"
+
+#include "apu_dbm.h"
+
+/* ### until we get the autoconf magic going... */
+#define APU_USE_SDBM
+
+#ifdef APU_USE_SDBM
+#include "sdbm.h"
+
+typedef SDBM *real_file_t;
+typedef sdbm_datum real_datum_t;
+
+#define APU_DBM_CLOSE(f)	sdbm_close(f)
+#define APU_DBM_FETCH(f, k)	sdbm_fetch((f), (k))
+#define APU_DBM_STORE(f, k, v)	sdbm_store((f), (k), (v), SDBM_REPLACE)
+#define APU_DBM_DELETE(f, k)	sdbm_delete((f), (k))
+#define APU_DBM_FIRSTKEY(f)	sdbm_firstkey(f)
+#define APU_DBM_NEXTKEY(f, k)	sdbm_nextkey(f)
+#define APU_DBM_FREEDATUM(f, d)	if (0) ; else	/* stop "no effect" warning */
+
+#define APU_DBM_DBMODE_RO       APR_READ
+#define APU_DBM_DBMODE_RW       (APR_READ | APR_WRITE)
+#define APU_DBM_DBMODE_RWCREATE (APR_READ | APR_WRITE | APR_CREATE)
+
+#elif defined(APU_USE_GDBM)
+#include <gdbm.h>
+#include <stdlib.h>     /* for free() */
+
+typedef GDBM_FILE real_file_t;
+typedef datum real_datum_t;
+
+#define APU_DBM_CLOSE(f)	gdbm_close(f)
+#define APU_DBM_FETCH(f, k)	gdbm_fetch((f), (k))
+#define APU_DBM_STORE(f, k, v)	g2s(gdbm_store((f), (k), (v), GDBM_REPLACE))
+#define APU_DBM_DELETE(f, k)	g2s(gdbm_delete((f), (k)))
+#define APU_DBM_FIRSTKEY(f)	gdbm_firstkey(f)
+#define APU_DBM_NEXTKEY(f, k)	gdbm_nextkey((f), (k))
+#define APU_DBM_FREEDATUM(f, d)	((d).dptr ? free((d).dptr) : 0)
+
+#define APU_DBM_DBMODE_RO       GDBM_READER
+#define APU_DBM_DBMODE_RW       GDBM_WRITER
+#define APU_DBM_DBMODE_RWCREATE GDBM_WRCREAT
+
+/* map a GDBM error to an apr_status_t */
+static apr_status_t g2s(int gerr)
+{
+    if (gerr == -1) {
+        /* ### need to fix this */
+        return APR_EINVAL;
+    }
+
+    return APR_SUCCESS;
+}
+
+#else
+#error a DBM implementation was not specified
+#endif
+
+
+struct apu_dbm_t
+{
+    apr_pool_t *pool;
+    real_file_t file;
+
+    int errcode;
+    const char *errmsg;
+};
+
+/* apu_datum <=> real_datum casting/conversions */
+#define A2R_DATUM(d)    (*(real_datum_t *)&(d))
+#define R2A_DATUM(d)    (*(apu_datum_t *)&(d))
+
+
+static apr_status_t set_error(apu_dbm_t *db)
+{
+    apr_status_t rv = APR_SUCCESS;
+
+#if defined(DAV_USE_SDBM)
+
+    if ((db->errcode = sdbm_error(db->file)) == 0) {
+        db->errmsg = NULL;
+    }
+    else {
+        db->errmsg = "I/O error occurred.";
+        rv = APR_EINVAL;        /* ### need something better */
+    }
+
+    /* captured it. clear it now. */
+    sdbm_clearerr(db->file);
+
+#elif defined(DAV_USE_GDBM)
+
+    if ((db->errcode = gdbm_errno) == GDBM_NO_ERROR) {
+        db->errmsg = NULL;
+    }
+    else {
+        db->errmsg = gdbm_strerror(gdbm_errno);
+        rv = APR_EINVAL;        /* ### need something better */
+    }
+
+    /* captured it. clear it now. */
+    gdbm_errno = GDBM_NO_ERROR;
+
+#endif
+
+    return rv;
+}
+
+apr_status_t apu_dbm_open(const char *pathname, apr_pool_t *pool, int mode,
+                          apu_dbm_t **pdb)
+{
+    real_file_t file;
+    int dbmode;
+
+    *pdb = NULL;
+
+    switch (mode) {
+    case APU_DBM_READONLY:
+        dbmode = APU_DBM_DBMODE_RO;
+        break;
+    case APU_DBM_READWRITE:
+        dbmode = APU_DBM_DBMODE_RW;
+        break;
+    case APU_DBM_RWCREATE:
+        dbmode = APU_DBM_DBMODE_RWCREATE;
+        break;
+    default:
+        return APR_EINVAL;
+    }
+
+#ifdef APU_USE_SDBM
+    {
+        apr_status_t rv;
+
+        rv = sdbm_open(&file, pathname, dbmode, APR_OS_DEFAULT, pool);
+        if (rv != APR_SUCCESS)
+            return rv;
+    }
+#else
+    {
+        /* Note: stupid cast to get rid of "const" on the pathname */
+        file = gdbm_open((char *) pathname, 0, dbmode, 0660, NULL);
+        if (file == NULL)
+            return APR_EINVAL;      /* ### need a better error */
+    }
+#endif
+
+    /* we have an open database... return it */
+    *pdb = apr_pcalloc(pool, sizeof(**pdb));
+    (*pdb)->pool = pool;
+    (*pdb)->file = file;
+
+    return APR_SUCCESS;
+}
+
+void apu_dbm_close(apu_dbm_t *db)
+{
+    APU_DBM_CLOSE(db->file);
+}
+
+apr_status_t apu_dbm_fetch(apu_dbm_t *db, apu_datum_t key, apu_datum_t *pvalue)
+{
+    *(real_datum_t *) pvalue = APU_DBM_FETCH(db->file, A2R_DATUM(key));
+
+    /* store the error info into DB, and return a status code. Also, note
+       that *pvalue should have been cleared on error. */
+    return set_error(db);
+}
+
+apr_status_t apu_dbm_store(apu_dbm_t *db, apu_datum_t key, apu_datum_t value)
+{
+    apr_status_t rv;
+
+    rv = APU_DBM_STORE(db->file, A2R_DATUM(key), A2R_DATUM(value));
+
+    /* ### is this the right handling of set_error() and rv? */
+
+    /* store the error info into DB, and return a status code. Also, note
+       that *pvalue should have been cleared on error. */
+    (void) set_error(db);
+
+    return rv;
+}
+
+apr_status_t apu_dbm_delete(apu_dbm_t *db, apu_datum_t key)
+{
+    apr_status_t rv;
+
+    rv = APU_DBM_DELETE(db->file, A2R_DATUM(key));
+
+    /* ### is this the right handling of set_error() and rv? */
+
+    /* store the error info into DB, and return a status code. Also, note
+       that *pvalue should have been cleared on error. */
+    (void) set_error(db);
+
+    return rv;
+}
+
+int apu_dbm_exists(apu_dbm_t *db, apu_datum_t key)
+{
+    int exists;
+
+#ifdef APU_USE_GDBM
+    exists = gdbm_exists(db->file, A2R_DATUM(key)) != 0;
+#else
+    {
+	sdbm_datum value = sdbm_fetch(db->file, A2R_DATUM(key));
+	sdbm_clearerr(db->file);	/* don't need the error */
+	exists = value.dptr != NULL;
+    }
+#endif
+    return 0;
+}
+
+apr_status_t apu_dbm_firstkey(apu_dbm_t *db, apu_datum_t *pkey)
+{
+    *(real_datum_t *) pkey = APU_DBM_FIRSTKEY(db->file);
+
+    /* store the error info into DB, and return a status code. Also, note
+       that *pvalue should have been cleared on error. */
+    return set_error(db);
+}
+
+apr_status_t apu_dbm_nextkey(apu_dbm_t *db, apu_datum_t *pkey)
+{
+    *(real_datum_t *) pkey = APU_DBM_NEXTKEY(db->file, A2R_DATUM(*pkey));
+
+    /* store the error info into DB, and return a status code. Also, note
+       that *pvalue should have been cleared on error. */
+    return set_error(db);
+}
+
+void apu_dbm_freedatum(apu_dbm_t *db, apu_datum_t data)
+{
+    APU_DBM_FREEDATUM(db, data);
+}
+
+void apu_dbm_geterror(apu_dbm_t *db, int *errcode, const char **errmsg)
+{
+    *errcode = db->errcode;
+    *errmsg = db->errmsg;
+}