Index: conf/dynamicmaps.cf
===================================================================
--- /dev/null
+++ conf/dynamicmaps.cf
@@ -0,0 +1,7 @@
+# Postfix dynamic maps configuration file.
+#
+# The first match found is the one that is used.
+# Wildcards are not supported.
+#
+#type   location of .so file                open function   (mkmap func)
+#====   ================================    =============   ============
Index: conf/postfix-files
===================================================================
--- conf/postfix-files.orig
+++ conf/postfix-files
@@ -65,6 +65,11 @@ $queue_directory/saved:d:$mail_owner:-:7
 $queue_directory/trace:d:$mail_owner:-:700:ucr
 $daemon_directory/anvil:f:root:-:755
 $daemon_directory/bounce:f:root:-:755
+$daemon_directory/dict_ldap.so:f:root:-:755
+$daemon_directory/dict_pcre.so:f:root:-:755
+$daemon_directory/dict_tcp.so:f:root:-:755
+$daemon_directory/dict_mysql.so:f:root:-:755
+$daemon_directory/dict_pgsql.so:f:root:-:755
 $daemon_directory/cleanup:f:root:-:755
 $daemon_directory/discard:f:root:-:755
 $daemon_directory/dnsblog:f:root:-:755
@@ -97,6 +102,11 @@ $daemon_directory/tlsmgr:f:root:-:755
 $daemon_directory/trivial-rewrite:f:root:-:755
 $daemon_directory/verify:f:root:-:755
 $daemon_directory/virtual:f:root:-:755
+/usr/lib/libpostfix-dns.so.1:f:root:-:755
+/usr/lib/libpostfix-global.so.1:f:root:-:755
+/usr/lib/libpostfix-tls.so.1:f:root:-:755
+/usr/lib/libpostfix-master.so.1:f:root:-:755
+/usr/lib/libpostfix-util.so.1:f:root:-:755
 $daemon_directory/nqmgr:h:$daemon_directory/qmgr
 $daemon_directory/lmtp:h:$daemon_directory/smtp
 $command_directory/postalias:f:root:-:755
@@ -120,6 +130,7 @@ $config_directory/access:f:root:-:644:p1
 $config_directory/aliases:f:root:-:644:p1
 $config_directory/bounce.cf.default:f:root:-:644:1
 $config_directory/canonical:f:root:-:644:p1
+$config_directory/dynamicmaps.cf:f:root:-:644:p
 $config_directory/cidr_table:f:root:-:644:o
 $config_directory/generic:f:root:-:644:p1
 $config_directory/generics:f:root:-:644:o
Index: src/dns/Makefile.in
===================================================================
--- src/dns/Makefile.in.orig
+++ src/dns/Makefile.in
@@ -14,7 +14,7 @@ LIBS	= ../../lib/libutil.a
 LIB_DIR	= ../../lib
 INC_DIR	= ../../include
 
-.c.o:;	$(CC) $(CFLAGS) -c $*.c
+.c.o:;	$(CC) -fPIC $(CFLAGS) -c $*.c
 
 all: $(LIB)
 
@@ -31,12 +31,10 @@ tests:	test dns_rr_to_pa_test dns_rr_to_
 root_tests:
 
 $(LIB):	$(OBJS)
-	$(AR) $(ARFL) $(LIB) $?
-	$(RANLIB) $(LIB)
+	gcc -shared -Wl,-soname,libpostfix-dns.so.1 -o $(LIB) $(OBJS) $(LIBS) $(SYSLIBS)
 
 $(LIB_DIR)/$(LIB): $(LIB)
 	cp $(LIB) $(LIB_DIR)
-	$(RANLIB) $(LIB_DIR)/$(LIB)
 
 update: $(LIB_DIR)/$(LIB) $(HDRS)
 	-for i in $(HDRS); \
Index: src/global/Makefile.in
===================================================================
--- src/global/Makefile.in.orig
+++ src/global/Makefile.in
@@ -3,7 +3,7 @@ SRCS	= abounce.c anvil_clnt.c been_here.
 	canon_addr.c cfg_parser.c cleanup_strerror.c cleanup_strflags.c \
 	clnt_stream.c conv_time.c db_common.c debug_peer.c debug_process.c \
 	defer.c deliver_completed.c deliver_flock.c deliver_pass.c \
-	deliver_request.c dict_ldap.c dict_mysql.c dict_pgsql.c \
+	deliver_request.c \
 	dict_proxy.c dict_sqlite.c domain_list.c dot_lockfile.c dot_lockfile_as.c \
 	dsb_scan.c dsn.c dsn_buf.c dsn_mask.c dsn_print.c dsn_util.c \
 	ehlo_mask.c ext_prop.c file_id.c flush_clnt.c header_opts.c \
@@ -37,7 +37,7 @@ OBJS	= abounce.o anvil_clnt.o been_here.
 	canon_addr.o cfg_parser.o cleanup_strerror.o cleanup_strflags.o \
 	clnt_stream.o conv_time.o db_common.o debug_peer.o debug_process.o \
 	defer.o deliver_completed.o deliver_flock.o deliver_pass.o \
-	deliver_request.o dict_ldap.o dict_mysql.o dict_pgsql.o \
+	deliver_request.o \
 	dict_proxy.o dict_sqlite.o domain_list.o dot_lockfile.o dot_lockfile_as.o \
 	dsb_scan.o dsn.o dsn_buf.o dsn_mask.o dsn_print.o dsn_util.o \
 	ehlo_mask.o ext_prop.o file_id.o flush_clnt.o header_opts.o \
@@ -112,10 +112,13 @@ LIBS	= ../../lib/libutil.a
 LIB_DIR	= ../../lib
 INC_DIR	= ../../include
 MAKES	=
+LDAPSO  = dict_ldap.so
+MYSQLSO = dict_mysql.so
+PGSQLSO = dict_pgsql.so
 
-.c.o:;	$(CC) $(CFLAGS) -c $*.c
+.c.o:;	$(CC) -fPIC $(CFLAGS) -c $*.c
 
-all: $(LIB)
+all: $(LIB) $(LDAPSO) $(MYSQLSO) $(PGSQLSO)
 
 $(OBJS): ../../conf/makedefs.out
 
@@ -125,14 +128,30 @@ Makefile: Makefile.in
 test:	$(TESTPROG)
 
 $(LIB):	$(OBJS)
-	$(AR) $(ARFL) $(LIB) $?
-	$(RANLIB) $(LIB)
+	gcc -shared -Wl,-soname,libpostfix-global.so.1 -o $(LIB) $(OBJS) $(LIBS) $(SYSLIBS)
+
+$(LDAPSO): dict_ldap.o
+	gcc -shared -Wl,-soname,dict_ldap.so -o $@ $? -lldap -llber -L../../lib -lutil -L. -lglobal
+
+$(MYSQLSO): dict_mysql.o
+	gcc -shared -Wl,-soname,dict_mysql.so -o $@ $? -L/usr/lib/mysql -lmysqlclient -L. -lutil -lglobal
+
+$(PGSQLSO): dict_pgsql.o
+	gcc -shared -Wl,-soname,dict_pgsql.so -o $@ $? -lpq -L. -lutil -lglobal
 
 $(LIB_DIR)/$(LIB): $(LIB)
 	cp $(LIB) $(LIB_DIR)
-	$(RANLIB) $(LIB_DIR)/$(LIB)
 
-update: $(LIB_DIR)/$(LIB) $(HDRS)
+$(LIB_DIR)/$(LDAPSO): $(LDAPSO)
+	cp $(LDAPSO) $(LIB_DIR)
+
+$(LIB_DIR)/$(MYSQLSO): $(MYSQLSO)
+	cp $(MYSQLSO) $(LIB_DIR)
+
+$(LIB_DIR)/$(PGSQLSO): $(PGSQLSO)
+	cp $(PGSQLSO) $(LIB_DIR)
+
+update: $(LIB_DIR)/$(LIB) $(LIB_DIR)/${LDAPSO} $(LIB_DIR)/${MYSQLSO} $(LIB_DIR)/${PGSQLSO} $(HDRS)
 	-for i in $(HDRS); \
 	do \
 	  cmp -s $$i $(INC_DIR)/$$i 2>/dev/null || cp $$i $(INC_DIR); \
@@ -577,7 +596,7 @@ lint:
 	lint $(DEFS) $(SRCS) $(LINTFIX)
 
 clean:
-	rm -f *.o $(LIB) *core $(TESTPROG) junk
+	rm -f *.o $(LIB) $(LDAPSO) $(MYSQLSO) $(PGSQLSO) *core $(TESTPROG) junk
 	rm -rf printfck
 
 tidy:	clean
Index: src/global/mail_conf.c
===================================================================
--- src/global/mail_conf.c.orig
+++ src/global/mail_conf.c
@@ -190,6 +190,13 @@ void    mail_conf_suck(void)
     if (dict_load_file_xt(CONFIG_DICT, path) == 0)
 	msg_fatal("open %s: %m", path);
     myfree(path);
+
+#ifndef NO_DYNAMIC_MAPS
+    path = concatenate(var_config_dir, "/", "dynamicmaps.cf", (char *) 0);
+    dict_open_dlinfo(path);
+    myfree(path);
+#endif
+
 }
 
 /* mail_conf_flush - discard configuration dictionary */
Index: src/global/mail_dict.c
===================================================================
--- src/global/mail_dict.c.orig
+++ src/global/mail_dict.c
@@ -47,6 +47,7 @@ typedef struct {
 
 static const DICT_OPEN_INFO dict_open_info[] = {
     DICT_TYPE_PROXY, dict_proxy_open,
+#ifndef MAX_DYNAMIC_MAPS
 #ifdef HAS_LDAP
     DICT_TYPE_LDAP, dict_ldap_open,
 #endif
@@ -60,6 +61,7 @@ static const DICT_OPEN_INFO dict_open_in
     DICT_TYPE_SQLITE, dict_sqlite_open,
 #endif
     DICT_TYPE_MEMCACHE, dict_memcache_open,
+#endif /* MAX_DYNAMIC_MAPS */
     0,
 };
 
Index: src/global/mail_params.c
===================================================================
--- src/global/mail_params.c.orig
+++ src/global/mail_params.c
@@ -79,6 +79,7 @@
 /*	char	*var_export_environ;
 /*	char	*var_debug_peer_list;
 /*	int	var_debug_peer_level;
+/*	int	var_command_maxtime;
 /*	int	var_in_flow_delay;
 /*	int	var_fault_inj_code;
 /*	char   *var_bounce_service;
@@ -268,6 +269,7 @@ char   *var_import_environ;
 char   *var_export_environ;
 char   *var_debug_peer_list;
 int     var_debug_peer_level;
+int	var_command_maxtime;
 int     var_fault_inj_code;
 char   *var_bounce_service;
 char   *var_cleanup_service;
@@ -279,6 +281,7 @@ char   *var_showq_service;
 char   *var_error_service;
 char   *var_flush_service;
 char   *var_verify_service;
+char   *var_scache_service;
 char   *var_trace_service;
 char   *var_proxymap_service;
 char   *var_proxywrite_service;
Index: src/global/mkmap_open.c
===================================================================
--- src/global/mkmap_open.c.orig
+++ src/global/mkmap_open.c
@@ -82,7 +82,7 @@
   * We use a different table (in dict_open.c) when querying maps.
   */
 typedef struct {
-    char   *type;
+    const char   *type;
     MKMAP  *(*before_open) (const char *);
 } MKMAP_OPEN_INFO;
 
@@ -161,7 +161,16 @@ MKMAP  *mkmap_open(const char *type, con
      */
     for (mp = mkmap_types; /* void */ ; mp++) {
 	if (mp->type == 0)
+#ifndef NO_DYNAMIC_MAPS
+	{
+	    static MKMAP_OPEN_INFO oi;
+	    oi.before_open=(MKMAP*(*)(const char*))dict_mkmap_func(type);
+	    oi.type=type;
+	    mp=&oi;
+	}
+#else
 	    msg_fatal("unsupported map type: %s", type);
+#endif
 	if (strcmp(type, mp->type) == 0)
 	    break;
     }
Index: src/master/Makefile.in
===================================================================
--- src/master/Makefile.in.orig
+++ src/master/Makefile.in
@@ -20,7 +20,7 @@ LIB_DIR	= ../../lib
 INC_DIR	= ../../include
 BIN_DIR	= ../../libexec
 
-.c.o:;	$(CC) $(CFLAGS) -c $*.c
+.c.o:;	$(CC) `for i in $(LIB_OBJ); do [ $$i = $@ ] && echo -fPIC; done` $(CFLAGS) -c $*.c
 
 all:	$(PROG) $(LIB)
 
@@ -39,12 +39,10 @@ tests:
 root_tests:
 
 $(LIB):	$(LIB_OBJ)
-	$(AR) $(ARFL) $(LIB) $?
-	$(RANLIB) $(LIB)
+	gcc -shared -Wl,-soname,libpostfix-master.so.1 -o $(LIB) $(LIB_OBJ) $(LIBS) $(SYSLIBS)
 
 $(LIB_DIR)/$(LIB): $(LIB)
 	cp $(LIB) $(LIB_DIR)/$(LIB)
-	$(RANLIB) $(LIB_DIR)/$(LIB)
 
 $(BIN_DIR)/$(PROG): $(PROG)
 	 cp $(PROG) $(BIN_DIR)
Index: src/milter/Makefile.in
===================================================================
--- src/milter/Makefile.in.orig
+++ src/milter/Makefile.in
@@ -14,7 +14,7 @@ LIB_DIR	= ../../lib
 INC_DIR	= ../../include
 MAKES	=
 
-.c.o:;	$(CC) $(CFLAGS) -c $*.c
+.c.o:;	$(CC) -fPIC $(CFLAGS) -c $*.c
 
 all: $(LIB)
 
@@ -30,12 +30,10 @@ tests:
 root_tests:
 
 $(LIB):	$(OBJS)
-	$(AR) $(ARFL) $(LIB) $?
-	$(RANLIB) $(LIB)
+	gcc -shared -Wl,-soname,libpostfix-milter.so.1 -o $(LIB) $(OBJS) $(LIBS) $(SYSLIBS)
 
 $(LIB_DIR)/$(LIB): $(LIB)
 	cp $(LIB) $(LIB_DIR)
-	$(RANLIB) $(LIB_DIR)/$(LIB)
 
 update: $(LIB_DIR)/$(LIB) $(HDRS)
 	-for i in $(HDRS); \
Index: src/postconf/Makefile.in
===================================================================
--- src/postconf/Makefile.in.orig
+++ src/postconf/Makefile.in
@@ -595,6 +595,7 @@ postconf_node.o: postconf_node.c
 postconf_other.o: ../../include/argv.h
 postconf_other.o: ../../include/dict.h
 postconf_other.o: ../../include/htable.h
+postconf_other.o: ../../include/mail_params.h
 postconf_other.o: ../../include/mbox_conf.h
 postconf_other.o: ../../include/sys_defs.h
 postconf_other.o: ../../include/vbuf.h
Index: src/postconf/postconf_other.c
===================================================================
--- src/postconf/postconf_other.c.orig
+++ src/postconf/postconf_other.c
@@ -46,10 +46,15 @@
 #include <vstream.h>
 #include <argv.h>
 #include <dict.h>
+#include <mymalloc.h>
+#include <safe.h>
+#include <stringops.h>
 
 /* Global library. */
 
 #include <mbox_conf.h>
+#include <mail_params.h>
+#include <mail_conf.h>
 
 /* XSASL library. */
 
@@ -66,6 +71,19 @@ void    show_maps(void)
     ARGV   *maps_argv;
     int     i;
 
+#ifndef NO_DYNAMIC_MAPS
+    char   *path;
+    char   *config_dir;
+
+    if (var_config_dir)
+        myfree(var_config_dir);
+    var_config_dir = mystrdup((config_dir = safe_getenv(CONF_ENV_PATH)) != 0 ?
+                             config_dir : DEF_CONFIG_DIR);     /* XXX */
+    path = concatenate(var_config_dir, "/", "dynamicmaps.cf", (char *) 0);
+    dict_open_dlinfo(path);
+    myfree(path);
+#endif
+
     maps_argv = dict_mapnames();
     for (i = 0; i < maps_argv->argc; i++)
 	vstream_printf("%s\n", maps_argv->argv[i]);
Index: src/postmap/postmap.c
===================================================================
--- src/postmap/postmap.c.orig
+++ src/postmap/postmap.c
@@ -5,7 +5,7 @@
 /*	Postfix lookup table management
 /* SYNOPSIS
 /* .fi
-/*	\fBpostmap\fR [\fB-Nbfhimnoprsvw\fR] [\fB-c \fIconfig_dir\fR]
+/*	\fBpostmap\fR [\fB-Nbfhimnoprsuvw\fR] [\fB-c \fIconfig_dir\fR]
 /*	[\fB-d \fIkey\fR] [\fB-q \fIkey\fR]
 /*		[\fIfile_type\fR:]\fIfile_name\fR ...
 /* DESCRIPTION
@@ -151,6 +151,8 @@
 /* .sp
 /*	This feature is available in Postfix version 2.2 and later,
 /*	and is not available for all database types.
+/* .IP \fB-u\fR
+/*	Upgrade the database to the current version.
 /* .IP \fB-v\fR
 /*	Enable verbose logging for debugging purposes. Multiple \fB-v\fR
 /*	options make the software increasingly verbose.
@@ -748,6 +750,18 @@ static void postmap_seq(const char *map_
     dict_close(dict);
 }
 
+/* postmap_upgrade - upgrade a map */
+
+static int postmap_upgrade(const char *map_type, const char *map_name)
+{
+    DICT   *dict;
+
+    dict = dict_open3(map_type, map_name, O_RDWR,
+			DICT_FLAG_LOCK|DICT_FLAG_UPGRADE);
+    dict_close(dict);
+    return (dict != 0);
+}
+
 /* usage - explain */
 
 static NORETURN usage(char *myname)
@@ -768,6 +782,7 @@ int     main(int argc, char **argv)
     int     postmap_flags = POSTMAP_FLAG_AS_OWNER | POSTMAP_FLAG_SAVE_PERM;
     int     open_flags = O_RDWR | O_CREAT | O_TRUNC;
     int     dict_flags = DICT_FLAG_DUP_WARN | DICT_FLAG_FOLD_FIX;
+    int     upgrade = 0;
     char   *query = 0;
     char   *delkey = 0;
     int     sequence = 0;
@@ -817,7 +832,7 @@ int     main(int argc, char **argv)
     /*
      * Parse JCL.
      */
-    while ((ch = GETOPT(argc, argv, "Nbc:d:fhimnopq:rsvw")) > 0) {
+    while ((ch = GETOPT(argc, argv, "Nbc:d:fhimnopq:rsuvw")) > 0) {
 	switch (ch) {
 	default:
 	    usage(argv[0]);
@@ -834,8 +849,8 @@ int     main(int argc, char **argv)
 		msg_fatal("out of memory");
 	    break;
 	case 'd':
-	    if (sequence || query || delkey)
-		msg_fatal("specify only one of -s -q or -d");
+	    if (sequence || query || delkey || upgrade)
+		msg_fatal("specify only one of -s -q -u or -d");
 	    delkey = optarg;
 	    break;
 	case 'f':
@@ -861,8 +876,8 @@ int     main(int argc, char **argv)
 	    postmap_flags &= ~POSTMAP_FLAG_SAVE_PERM;
 	    break;
 	case 'q':
-	    if (sequence || query || delkey)
-		msg_fatal("specify only one of -s -q or -d");
+	    if (sequence || query || delkey || upgrade)
+		msg_fatal("specify only one of -s -q -u or -d");
 	    query = optarg;
 	    break;
 	case 'r':
@@ -870,10 +885,15 @@ int     main(int argc, char **argv)
 	    dict_flags |= DICT_FLAG_DUP_REPLACE;
 	    break;
 	case 's':
-	    if (query || delkey)
-		msg_fatal("specify only one of -s or -q or -d");
+	    if (query || delkey || upgrade)
+		msg_fatal("specify only one of -s or -q -u or -d");
 	    sequence = 1;
 	    break;
+	case 'u':
+	    if (sequence || query || delkey || upgrade)
+		msg_fatal("specify only one of -s -q -u or -d");
+	    upgrade=1;
+	    break;
 	case 'v':
 	    msg_verbose++;
 	    break;
@@ -944,6 +964,21 @@ int     main(int argc, char **argv)
 	    exit(0);
 	}
 	exit(1);
+    } else if (upgrade) {			/* Upgrade the map(s) */
+	int success = 1;
+	if (optind + 1 > argc)
+	    usage(argv[0]);
+	while (optind < argc) {
+	    if ((path_name = split_at(argv[optind], ':')) != 0) {
+		success &= postmap_upgrade(argv[optind], path_name);
+	    } else {
+		success &= postmap_upgrade(var_db_type, path_name);
+	    }
+	    if (!success)
+		exit(1);
+	    optind++;
+	}
+	exit(0);
     } else {					/* create/update map(s) */
 	if (optind + 1 > argc)
 	    usage(argv[0]);
Index: src/tls/Makefile.in
===================================================================
--- src/tls/Makefile.in.orig
+++ src/tls/Makefile.in
@@ -24,7 +24,7 @@ LIB_DIR	= ../../lib
 INC_DIR	= ../../include
 MAKES	=
 
-.c.o:;	$(CC) $(CFLAGS) -c $*.c
+.c.o:;	$(CC) -fPIC $(CFLAGS) -c $*.c
 
 all: $(LIB)
 
@@ -40,12 +40,10 @@ tests:
 root_tests:
 
 $(LIB):	$(OBJS)
-	$(AR) $(ARFL) $(LIB) $?
-	$(RANLIB) $(LIB)
+	gcc -shared -Wl,-soname,libpostfix-tls.so.1 -o $(LIB) $(OBJS) $(LIBS) $(SYSLIBS)
 
 $(LIB_DIR)/$(LIB): $(LIB)
 	cp $(LIB) $(LIB_DIR)
-	$(RANLIB) $(LIB_DIR)/$(LIB)
 
 update: $(LIB_DIR)/$(LIB) $(HDRS)
 	-for i in $(HDRS); \
Index: src/tls/tls_client.c
===================================================================
--- src/tls/tls_client.c.orig
+++ src/tls/tls_client.c
@@ -156,6 +156,8 @@
 #define STR	vstring_str
 #define LEN	VSTRING_LEN
 
+int var_tls_daemon_rand_bytes;
+
 /* load_clnt_session - load session from client cache (non-callback) */
 
 static SSL_SESSION *load_clnt_session(TLS_SESS_STATE *TLScontext)
Index: src/tls/tls_server.c
===================================================================
--- src/tls/tls_server.c.orig
+++ src/tls/tls_server.c
@@ -155,6 +155,8 @@
 #define STR(x)	vstring_str(x)
 #define LEN(x)	VSTRING_LEN(x)
 
+int var_tls_daemon_rand_bytes;
+
 /* Application-specific. */
 
  /*
Index: src/util/Makefile.in
===================================================================
--- src/util/Makefile.in.orig
+++ src/util/Makefile.in
@@ -34,15 +34,16 @@ SRCS	= alldig.c allprint.c argv.c argv_s
 	unix_pass_listen.c unix_pass_trigger.c edit_file.c inet_windowsize.c \
 	unix_pass_fd_fix.c dict_cache.c valid_utf_8.c dict_thash.c \
 	ip_match.c nbbio.c stream_pass_connect.c base32_code.c dict_test.c \
-	dict_fail.c msg_rate_delay.c dict_surrogate.c warn_stat.c
+	dict_fail.c msg_rate_delay.c dict_surrogate.c warn_stat.c \
+	load_lib.c sdbm.c
 OBJS	= alldig.o allprint.o argv.o argv_split.o attr_clnt.o attr_print0.o \
 	attr_print64.o attr_print_plain.o attr_scan0.o attr_scan64.o \
 	attr_scan_plain.o auto_clnt.o base64_code.o basename.o binhash.o \
 	chroot_uid.o cidr_match.o clean_env.o close_on_exec.o concatenate.o \
 	ctable.o dict.o dict_alloc.o dict_cdb.o dict_cidr.o dict_db.o \
 	dict_dbm.o dict_debug.o dict_env.o dict_ht.o dict_ni.o dict_nis.o \
-	dict_nisplus.o dict_open.o dict_pcre.o dict_regexp.o dict_sdbm.o \
-	dict_static.o dict_tcp.o dict_unix.o dir_forest.o doze.o dummy_read.o \
+	dict_nisplus.o dict_open.o dict_regexp.o dict_sdbm.o \
+	dict_static.o dict_unix.o dir_forest.o doze.o dummy_read.o \
 	dummy_write.o duplex_pipe.o environ.o events.o exec_command.o \
 	fifo_listen.o fifo_trigger.o file_limit.o find_inet.o fsspace.o \
 	fullname.o get_domainname.o get_hostname.o hex_code.o hex_quote.o \
@@ -70,7 +71,8 @@ OBJS	= alldig.o allprint.o argv.o argv_s
 	unix_pass_listen.o unix_pass_trigger.o edit_file.o inet_windowsize.o \
 	unix_pass_fd_fix.o dict_cache.o valid_utf_8.o dict_thash.o \
 	ip_match.o nbbio.o stream_pass_connect.o base32_code.o dict_test.o \
-	dict_fail.o msg_rate_delay.o dict_surrogate.o warn_stat.o
+	dict_fail.o msg_rate_delay.o dict_surrogate.o warn_stat.o \
+	load_lib.o sdbm.o
 HDRS	= argv.h attr.h attr_clnt.h auto_clnt.h base64_code.h binhash.h \
 	chroot_uid.h cidr_match.h clean_env.h connect.h ctable.h dict.h \
 	dict_cdb.h dict_cidr.h dict_db.h dict_dbm.h dict_env.h dict_ht.h \
@@ -84,7 +86,7 @@ HDRS	= argv.h attr.h attr_clnt.h auto_cl
 	msg_output.h msg_syslog.h msg_vstream.h mvect.h myaddrinfo.h myflock.h \
 	mymalloc.h myrand.h name_code.h name_mask.h netstring.h nvtable.h \
 	open_as.h open_lock.h percentm.h posix_signals.h readlline.h ring.h \
-	safe.h safe_open.h sane_accept.h sane_connect.h sane_fsops.h \
+	safe.h safe_open.h sane_accept.h sane_connect.h sane_fsops.h sdbm.h load_lib.h \
 	sane_socketpair.h sane_time.h scan_dir.h set_eugid.h set_ugid.h \
 	sigdelay.h sock_addr.h spawn_command.h split_at.h stat_as.h \
 	stringops.h sys_defs.h timed_connect.h timed_wait.h trigger.h \
@@ -98,6 +100,8 @@ DEFS	= -I. -D$(SYSTYPE)
 CFLAGS	= $(DEBUG) $(OPT) $(DEFS)
 FILES	= Makefile $(SRCS) $(HDRS)
 INCL	=
+PCRESO  = dict_pcre.so
+TCPSO   = dict_tcp.so
 LIB	= libutil.a
 TESTPROG= dict_open dup2_pass_on_exec events exec_command fifo_open \
 	fifo_rdonly_bug fifo_rdwr_bug fifo_trigger fsspace fullname \
@@ -113,10 +117,11 @@ TESTPROG= dict_open dup2_pass_on_exec ev
 
 LIB_DIR	= ../../lib
 INC_DIR	= ../../include
+LIBS    = $(LIB_DIR)/$(LIB) $(LIB_DIR)/$(PCRESO) $(LIB_DIR)/$(TCPSO)
 
-.c.o:;	$(CC) $(CFLAGS) -c $*.c
+.c.o:;	$(CC) -fPIC $(CFLAGS) -c $*.c
 
-all: $(LIB)
+all: $(LIB) $(PCRESO) $(TCPSO)
 
 $(OBJS): ../../conf/makedefs.out
 
@@ -125,15 +130,25 @@ Makefile: Makefile.in
 
 test:	$(TESTPROG)
 
+$(PCRESO): dict_pcre.o
+	gcc -shared -Wl,-soname,dict_pcre.so -o $@ $? -lpcre -L. -lutil
+
+$(TCPSO): dict_tcp.o
+	gcc -shared -Wl,-soname,dict_tcp.so -o $@ $? -L. -lutil
+
 $(LIB):	$(OBJS)
-	$(AR) $(ARFL) $(LIB) $?
-	$(RANLIB) $(LIB)
+	gcc -shared -Wl,-soname,libpostfix-util.so.1 -o $(LIB) $(OBJS) -ldl $(SYSLIBS)
 
 $(LIB_DIR)/$(LIB): $(LIB)
 	cp $(LIB) $(LIB_DIR)
-	$(RANLIB) $(LIB_DIR)/$(LIB)
 
-update: $(LIB_DIR)/$(LIB) $(HDRS)
+$(LIB_DIR)/$(PCRESO): $(PCRESO)
+	cp $(PCRESO) $(LIB_DIR)
+
+$(LIB_DIR)/$(TCPSO): $(TCPSO)
+	cp $(TCPSO) $(LIB_DIR)
+
+update: $(LIBS) $(HDRS)
 	-for i in $(HDRS); \
 	do \
 	  cmp -s $$i $(INC_DIR)/$$i 2>/dev/null || cp $$i $(INC_DIR); \
@@ -155,7 +170,8 @@ lint:
 	lint $(DEFS) $(SRCS) $(LINTFIX)
 
 clean:
-	rm -f *.o $(LIB) *core $(TESTPROG) junk $(MAKES) *.tmp
+	rm -f *.o $(LIB) $(PCRESO) $(TCPSO) *core $(TESTPROG) \
+		junk $(MAKES) *.tmp
 	rm -rf printfck
 
 tidy:	clean
Index: src/util/dict.h
===================================================================
--- src/util/dict.h.orig
+++ src/util/dict.h
@@ -80,6 +80,7 @@ extern DICT *dict_debug(DICT *);
 #define DICT_FLAG_NO_UNAUTH	(1<<13)	/* disallow unauthenticated data */
 #define DICT_FLAG_FOLD_FIX	(1<<14)	/* case-fold key with fixed-case map */
 #define DICT_FLAG_FOLD_MUL	(1<<15)	/* case-fold key with multi-case map */
+#define DICT_FLAG_UPGRADE	(1<<30) /* Upgrade the db */
 #define DICT_FLAG_FOLD_ANY	(DICT_FLAG_FOLD_FIX | DICT_FLAG_FOLD_MUL)
 #define DICT_FLAG_OPEN_LOCK	(1<<16)	/* open file with exclusive lock */
 
@@ -166,6 +167,11 @@ extern int dict_error(const char *);
 extern DICT *dict_open(const char *, int, int);
 extern DICT *dict_open3(const char *, const char *, int, int);
 extern void dict_open_register(const char *, DICT *(*) (const char *, int, int));
+#ifndef NO_DYNAMIC_MAPS
+extern void dict_open_dlinfo(const char *path);
+typedef void* (*dict_mkmap_func_t)(const char *);
+dict_mkmap_func_t dict_mkmap_func(const char *dict_type);
+#endif
 
 #define dict_get(dp, key)	((const char *) (dp)->lookup((dp), (key)))
 #define dict_put(dp, key, val)	(dp)->update((dp), (key), (val))
Index: src/util/dict_db.c
===================================================================
--- src/util/dict_db.c.orig
+++ src/util/dict_db.c
@@ -693,6 +693,12 @@ static DICT *dict_db_open(const char *cl
 	msg_fatal("set DB cache size %d: %m", dict_db_cache_size);
     if (type == DB_HASH && db->set_h_nelem(db, DICT_DB_NELM) != 0)
 	msg_fatal("set DB hash element count %d: %m", DICT_DB_NELM);
+    if (dict_flags & DICT_FLAG_UPGRADE) {
+       if (msg_verbose)
+           msg_info("upgrading database %s",db_path);
+       if ((errno = db->upgrade(db,db_path,0)) != 0)
+           msg_fatal("upgrade of database %s: %m",db_path);
+    }
 #if DB_VERSION_MAJOR == 5 || (DB_VERSION_MAJOR == 4 && DB_VERSION_MINOR > 0)
     if ((errno = db->open(db, 0, db_path, 0, type, db_flags, 0644)) != 0)
 	FREE_RETURN(dict_surrogate(class, path, open_flags, dict_flags,
Index: src/util/dict_dbm.c
===================================================================
--- src/util/dict_dbm.c.orig
+++ src/util/dict_dbm.c
@@ -417,6 +417,10 @@ DICT   *dict_dbm_open(const char *path,
     char   *dbm_path;
     int     lock_fd;
 
+#ifdef HAVE_GDBM
+    msg_fatal("%s: gdbm maps use locking that is incompatible with postfix.  Use a hash map instead.",
+		 path);
+#endif
     /*
      * Note: DICT_FLAG_LOCK is used only by programs that do fine-grained (in
      * the time domain) locking while accessing individual database records.
Index: src/util/dict_open.c
===================================================================
--- src/util/dict_open.c.orig
+++ src/util/dict_open.c
@@ -44,6 +44,8 @@
 /*	DICT	*(*open) (const char *, int, int);
 /*
 /*	ARGV	*dict_mapnames()
+/*
+/*	void (*)() dict_mkmap_func(const char *dict_type)
 /* DESCRIPTION
 /*	This module implements a low-level interface to multiple
 /*	physical dictionary types.
@@ -166,6 +168,9 @@
 /*
 /*	dict_mapnames() returns a sorted list with the names of all available
 /*	dictionary types.
+/*
+/*	dict_mkmap_func() returns a pointer to the mkmap setup function
+/*	for the given map type, as given in /etc/dynamicmaps.cf
 /* DIAGNOSTICS
 /*	Fatal error: open error, unsupported dictionary type, attempt to
 /*	update non-writable dictionary.
@@ -213,6 +218,9 @@
 #include <strings.h>
 #endif
 
+#include <sys/stat.h>
+#include <unistd.h>
+
 /* Utility library. */
 
 #include <argv.h>
@@ -241,6 +249,27 @@
 #include <htable.h>
 #include <myflock.h>
 
+#ifndef NO_DYNAMIC_MAPS
+#include <load_lib.h>
+#include <vstring.h>
+#include <vstream.h>
+#include <vstring_vstream.h>
+#include <mvect.h>
+
+ /*
+  * Interface for dynamic map loading.
+  */
+typedef struct {
+    const char  *pattern;
+    const char  *soname;
+    const char  *openfunc;
+    const char  *mkmapfunc;
+} DLINFO;
+
+static DLINFO *dict_dlinfo;
+static DLINFO *dict_open_dlfind(const char *type);
+#endif
+
  /*
   * lookup table for available map types.
   */
@@ -256,7 +285,9 @@ static const DICT_OPEN_INFO dict_open_in
     DICT_TYPE_ENVIRON, dict_env_open,
     DICT_TYPE_HT, dict_ht_open,
     DICT_TYPE_UNIX, dict_unix_open,
+#ifndef MAX_DYNAMIC_MAPS
     DICT_TYPE_TCP, dict_tcp_open,
+#endif
 #ifdef HAS_SDBM
     DICT_TYPE_SDBM, dict_sdbm_open,
 #endif
@@ -276,9 +307,11 @@ static const DICT_OPEN_INFO dict_open_in
 #ifdef HAS_NETINFO
     DICT_TYPE_NETINFO, dict_ni_open,
 #endif
+#ifndef MAX_DYNAMIC_MAPS
 #ifdef HAS_PCRE
     DICT_TYPE_PCRE, dict_pcre_open,
 #endif
+#endif /* MAX_DYNAMIC_MAPS */
 #ifdef HAS_POSIX_REGEXP
     DICT_TYPE_REGEXP, dict_regexp_open,
 #endif
@@ -338,9 +371,32 @@ DICT   *dict_open3(const char *dict_type
 		  dict_type, dict_name);
     if (dict_open_hash == 0)
 	dict_open_init();
-    if ((dp = (DICT_OPEN_INFO *) htable_find(dict_open_hash, dict_type)) == 0)
+    if ((dp = (DICT_OPEN_INFO *) htable_find(dict_open_hash, dict_type)) == 0) {
+#ifdef NO_DYNAMIC_MAPS
 	return (dict_surrogate(dict_type, dict_name, open_flags, dict_flags,
 			     "unsupported dictionary type: %s", dict_type));
+#else
+       struct stat st;
+       LIB_FN fn[2];
+       DICT *(*open) (const char *, int, int);
+       DLINFO *dl=dict_open_dlfind(dict_type);
+       if (!dl)
+           msg_fatal("%s: unsupported dictionary type: %s:  Is the postfix-%s package installed?", myname, dict_type, dict_type);
+       if (stat(dl->soname,&st) < 0) {
+           msg_fatal("%s: unsupported dictionary type: %s (%s not found.  Is the postfix-%s package installed?)",
+               myname, dict_type, dl->soname, dict_type);
+       }
+       fn[0].name = dl->openfunc;
+       fn[0].ptr  = (void**)&open;
+       fn[1].name = NULL;
+       load_library_symbols(dl->soname, fn, NULL);
+       dict_open_register(dict_type, open);
+       dp = (DICT_OPEN_INFO *) htable_find(dict_open_hash, dict_type);
+#endif
+    }
+    if (msg_verbose>1) {
+       msg_info("%s: calling %s open routine",myname,dict_type);
+    }
     if ((dict = dp->open(dict_name, open_flags, dict_flags)) == 0)
 	return (dict_surrogate(dict_type, dict_name, open_flags, dict_flags,
 			    "cannot open %s:%s: %m", dict_type, dict_name));
@@ -359,6 +415,36 @@ DICT   *dict_open3(const char *dict_type
     return (dict);
 }
 
+dict_mkmap_func_t dict_mkmap_func(const char *dict_type)
+{
+    char   *myname="dict_mkmap_func";
+    struct stat st;
+    LIB_FN fn[2];
+    dict_mkmap_func_t mkmap;
+    DLINFO *dl;
+#ifndef NO_DYNAMIC_MAPS
+    if (!dict_dlinfo)
+	msg_fatal("dlinfo==NULL");
+    dl=dict_open_dlfind(dict_type);
+    if (!dl)
+	msg_fatal("%s: unsupported dictionary type: %s:  Is the postfix-%s package installed?", myname, dict_type, dict_type);
+    if (stat(dl->soname,&st) < 0) {
+	msg_fatal("%s: unsupported dictionary type: %s (%s not found.  Is the postfix-%s package installed?)",
+	    myname, dict_type, dl->soname, dict_type);
+    }
+    if (!dl->mkmapfunc)
+	msg_fatal("%s: unsupported dictionary type: %s does not allow map creation.", myname, dict_type);
+
+    fn[0].name = dl->mkmapfunc;
+    fn[0].ptr  = (void**)&mkmap;
+    fn[1].name = NULL;
+    load_library_symbols(dl->soname, fn, NULL);
+    return mkmap;
+#else
+    return (void(*)())NULL;
+#endif
+}
+
 /* dict_open_register - register dictionary type */
 
 void    dict_open_register(const char *type,
@@ -392,6 +478,9 @@ ARGV   *dict_mapnames()
     HTABLE_INFO **ht;
     DICT_OPEN_INFO *dp;
     ARGV   *mapnames;
+#ifndef NO_DYNAMIC_MAPS
+    DLINFO *dlp;
+#endif
 
     if (dict_open_hash == 0)
 	dict_open_init();
@@ -400,6 +489,13 @@ ARGV   *dict_mapnames()
 	dp = (DICT_OPEN_INFO *) ht[0]->value;
 	argv_add(mapnames, dp->type, ARGV_END);
     }
+#ifndef NO_DYNAMIC_MAPS
+    if (!dict_dlinfo)
+	msg_fatal("dlinfo==NULL");
+    for (dlp=dict_dlinfo; dlp->pattern; dlp++) {
+	argv_add(mapnames, dlp->pattern, ARGV_END);
+    }
+#endif
     qsort((void *) mapnames->argv, mapnames->argc, sizeof(mapnames->argv[0]),
 	  dict_sort_alpha_cpp);
     myfree((char *) ht_info);
@@ -407,6 +503,87 @@ ARGV   *dict_mapnames()
     return mapnames;
 }
 
+#ifndef NO_DYNAMIC_MAPS
+#define	STREQ(x,y) (x == y || (x[0] == y[0] && strcmp(x,y) == 0))
+
+void dict_open_dlinfo(const char *path)
+{
+    char    *myname="dict_open_dlinfo";
+    VSTREAM *conf_fp=vstream_fopen(path,O_RDONLY,0);
+    VSTRING *buf = vstring_alloc(100);
+    char    *cp;
+    ARGV    *argv;
+    MVECT    vector;
+    int      nelm=0;
+    int      linenum=0;
+
+    dict_dlinfo=(DLINFO*)mvect_alloc(&vector,sizeof(DLINFO),3,NULL,NULL);
+
+    if (!conf_fp) {
+	msg_warn("%s: cannot open %s.  No dynamic maps will be allowed.",
+		myname, path);
+    } else {
+	while (vstring_get_nonl(buf,conf_fp) != VSTREAM_EOF) {
+	    cp = vstring_str(buf);
+	    linenum++;
+	    if (*cp == '#' || *cp == '\0')
+		continue;
+	    argv = argv_split(cp, " \t");
+	    if (argv->argc != 3 && argv->argc != 4) {
+		msg_fatal("%s: Expected \"pattern .so-name open-function [mkmap-function]\" at line %d",
+			  myname, linenum);
+	    }
+	    if (STREQ(argv->argv[0],"*")) {
+		msg_warn("%s: wildcard dynamic map entry no longer supported.",
+			  myname);
+		continue;
+	    }
+	    if (argv->argv[1][0] != '/') {
+		msg_fatal("%s: .so name must begin with a \"/\" at line %d",
+			  myname, linenum);
+	    }
+	    if (nelm >= vector.nelm) {
+		dict_dlinfo=(DLINFO*)mvect_realloc(&vector,vector.nelm+3);
+	    }
+	    dict_dlinfo[nelm].pattern  = mystrdup(argv->argv[0]);
+	    dict_dlinfo[nelm].soname   = mystrdup(argv->argv[1]);
+	    dict_dlinfo[nelm].openfunc = mystrdup(argv->argv[2]);
+	    if (argv->argc==4)
+		dict_dlinfo[nelm].mkmapfunc = mystrdup(argv->argv[3]);
+	    else
+		dict_dlinfo[nelm].mkmapfunc = NULL;
+	    nelm++;
+	    argv_free(argv);
+	}
+    }
+    if (nelm >= vector.nelm) {
+	dict_dlinfo=(DLINFO*)mvect_realloc(&vector,vector.nelm+1);
+    }
+    dict_dlinfo[nelm].pattern  = NULL;
+    dict_dlinfo[nelm].soname   = NULL;
+    dict_dlinfo[nelm].openfunc = NULL;
+    dict_dlinfo[nelm].mkmapfunc = NULL;
+    if (conf_fp)
+	vstream_fclose(conf_fp);
+    vstring_free(buf);
+}
+
+static DLINFO *dict_open_dlfind(const char *type)
+{
+    DLINFO *dp;
+
+    if (!dict_dlinfo)
+	return NULL;
+
+    for (dp=dict_dlinfo; dp->pattern; dp++) {
+	if (STREQ(dp->pattern,type))
+	    return dp;
+    }
+    return NULL;
+}
+
+#endif /* !NO_DYNAMIC_MAPS */
+
 #ifdef TEST
 
  /*
Index: src/util/load_lib.c
===================================================================
--- /dev/null
+++ src/util/load_lib.c
@@ -0,0 +1,135 @@
+/*++
+/* NAME
+/*	load_lib 3
+/* SUMMARY
+/*	library loading wrappers
+/* SYNOPSIS
+/*	#include <load_lib.h>
+/*
+/*	extern int  load_library_symbols(const char *, LIB_FN *, LIB_FN *);
+/*	const char *libname;
+/*      LIB_FN     *libfuncs;
+/*      LIB_FN     *libdata;
+/*
+/* DESCRIPTION
+/*	This module loads functions from libraries, returnine pointers
+/*	to the named functions.
+/*
+/*	load_library_symbols() loads all of the desired functions, and
+/*	returns zero for success, or exits via msg_fatal().
+/*
+/* SEE ALSO
+/*	msg(3) diagnostics interface
+/* DIAGNOSTICS
+/*	Problems are reported via the msg(3) diagnostics routines:
+/*	library not found, symbols not found, other fatal errors.
+/* LICENSE
+/* .ad
+/* .fi
+/*	The Secure Mailer license must be distributed with this software.
+/* AUTHOR(S)
+/*	LaMont Jones
+/*	Hewlett-Packard Company
+/*	3404 Harmony Road
+/*	Fort Collins, CO 80528, USA
+/*
+/*	Wietse Venema
+/*	IBM T.J. Watson Research
+/*	P.O. Box 704
+/*	Yorktown Heights, NY 10598, USA
+/*--*/
+
+/* System libraries. */
+
+#include "sys_defs.h"
+#include <stdlib.h>
+#include <stddef.h>
+#include <string.h>
+#if defined(HAS_DLOPEN)
+#include <dlfcn.h>
+#elif defined(HAS_SHL_LOAD)
+#include <dl.h>
+#endif
+
+/* Application-specific. */
+
+#include "msg.h"
+#include "load_lib.h"
+
+extern int  load_library_symbols(const char * libname, LIB_FN * libfuncs, LIB_FN * libdata)
+{
+    char   *myname = "load_library_symbols";
+    LIB_FN *fn;
+
+#if defined(HAS_DLOPEN)
+    void   *handle;
+    char   *emsg;
+
+    handle=dlopen(libname,RTLD_NOW);
+    emsg=dlerror();
+    if (emsg) {
+	msg_fatal("%s: dlopen failure loading %s: %s", myname, libname, emsg);
+    }
+
+    if (libfuncs) {
+	for (fn=libfuncs; fn->name; fn++) {
+	    *(fn->ptr) = dlsym(handle,fn->name);
+	    emsg=dlerror();
+	    if (emsg) {
+		msg_fatal("%s: dlsym failure looking up %s in %s: %s", myname,
+			  fn->name, libname, emsg);
+	    }
+	    if (msg_verbose>1) {
+		msg_info("loaded %s = %lx",fn->name, *((long*)(fn->ptr)));
+	    }
+	}
+    }
+
+    if (libdata) {
+	for (fn=libdata; fn->name; fn++) {
+	    *(fn->ptr) = dlsym(handle,fn->name);
+	    emsg=dlerror();
+	    if (emsg) {
+		msg_fatal("%s: dlsym failure looking up %s in %s: %s", myname,
+			  fn->name, libname, emsg);
+	    }
+	    if (msg_verbose>1) {
+		msg_info("loaded %s = %lx",fn->name, *((long*)(fn->ptr)));
+	    }
+	}
+    }
+#elif defined(HAS_SHL_LOAD)
+    shl_t   handle;
+
+    handle = shl_load(libname,BIND_IMMEDIATE,0);
+
+    if (libfuncs) {
+	for (fn=libfuncs; fn->name; fn++) {
+	    if (shl_findsym(&handle,fn->name,TYPE_PROCEDURE,fn->ptr) != 0) {
+		msg_fatal("%s: shl_findsym failure looking up %s in %s: %m",
+			  myname, fn->name, libname);
+	    }
+	    if (msg_verbose>1) {
+		msg_info("loaded %s = %x",fn->name, *((long*)(fn->ptr)));
+	    }
+	}
+    }
+
+    if (libdata) {
+	for (fn=libdata; fn->name; fn++) {
+	    if (shl_findsym(&handle,fn->name,TYPE_DATA,fn->ptr) != 0) {
+		msg_fatal("%s: shl_findsym failure looking up %s in %s: %m",
+			  myname, fn->name, libname);
+	    }
+	    if (msg_verbose>1) {
+		msg_info("loaded %s = %x",fn->name, *((long*)(fn->ptr)));
+	    }
+	}
+    }
+
+#else
+    msg_fatal("%s: need dlopen or shl_load support for dynamic libraries",
+		myname);
+#endif
+    return 0;
+}
Index: src/util/load_lib.h
===================================================================
--- /dev/null
+++ src/util/load_lib.h
@@ -0,0 +1,41 @@
+#ifndef _LOAD_LIB_H_INCLUDED_
+#define _LOAD_LIB_H_INCLUDED_
+
+/*++
+/* NAME
+/*	load_lib 3h
+/* SUMMARY
+/*	library loading wrappers
+/* SYNOPSIS
+/*	#include "load_lib.h"
+/* DESCRIPTION
+/* .nf
+
+ /*
+  * External interface.
+  */
+/* NULL name terminates list */
+typedef struct LIB_FN {
+    const char *name;
+    void       **ptr;
+} LIB_FN;
+
+extern int  load_library_symbols(const char *, LIB_FN *, LIB_FN *);
+
+/* LICENSE
+/* .ad
+/* .fi
+/*	The Secure Mailer license must be distributed with this software.
+/* AUTHOR(S)
+/*	LaMont Jones
+/*	Hewlett-Packard Company
+/*	3404 Harmony Road
+/*	Fort Collins, CO 80528, USA
+/*
+/*	Wietse Venema
+/*	IBM T.J. Watson Research
+/*	P.O. Box 704
+/*	Yorktown Heights, NY 10598, USA
+/*--*/
+
+#endif
Index: src/util/sdbm.c
===================================================================
--- /dev/null
+++ src/util/sdbm.c
@@ -0,0 +1,972 @@
+/*++
+/* NAME
+/*      sdbm 3h
+/* SUMMARY
+/*      SDBM Simple DBM: ndbm work-alike hashed database library
+/* SYNOPSIS
+/*      include "sdbm.h"
+/* DESCRIPTION
+/*	This file includes the public domain 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: public domain
+/*	The file has been patched following the advice of Uwe Ohse
+/*	<uwe@ohse.de>:
+/*	--------------------------------------------------------------
+/*	this patch fixes a problem with sdbms .dir file, which arrises when
+/*	a second .dir block is needed for the first time. read() returns 0
+/*	in that case, and the library forgot to initialize that new block.
+/*
+/*	A related problem is that the calculation of db->maxbno is wrong.
+/*	It just appends 4096*BYTESIZ bits, which is not enough except for
+/*	small databases (.dir basically doubles everytime it's too small).
+/*	--------------------------------------------------------------
+/*	According to Uwe Ohse, the patch has also been submitted to the
+/*	author of SDBM. (The 4096*BYTESIZ bits comment may apply with a
+/*	different size for Postfix/TLS, as the patch was sent against the
+/*	original SDBM distributiona and for Postfix/TLS I have changed the
+/*	default sizes.
+/* .nf
+/*--*/
+
+/*
+ * 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: public domain.
+ *
+ * core routines
+ */
+
+#include <stdio.h>
+#include <stdlib.h>
+#ifdef WIN32
+#include <io.h>
+#include <errno.h>
+#else
+#include <unistd.h>
+#endif
+#include <sys/types.h>
+#include <sys/stat.h>
+#include <fcntl.h>
+#include <errno.h>
+#include <string.h>
+#ifdef __STDC__
+#include <stddef.h>
+#endif
+#include <mymalloc.h>
+
+#include <sdbm.h>
+
+/*
+ * useful macros
+ */
+#define bad(x)          ((x).dptr == NULL || (x).dsize <= 0)
+#define exhash(item)    sdbm_hash((item).dptr, (item).dsize)
+#define ioerr(db)       ((db)->flags |= DBM_IOERR)
+
+#define OFF_PAG(off)    (long) (off) * PBLKSIZ
+#define OFF_DIR(off)    (long) (off) * DBLKSIZ
+
+static 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
+};
+
+datum   nullitem =
+{NULL, 0};
+
+typedef struct
+{
+    int     dirf;			/* directory file descriptor */
+    int     pagf;			/* page file descriptor */
+    int     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;			/* page file block buffer */
+    long    dirbno;			/* current block in dirbuf */
+    char   *dirbuf;			/* directory file block buffer */
+}       DBM;
+
+
+/* ************************* */
+
+/*
+ * 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: public domain. keep it that way.
+ *
+ * hashing routine
+ */
+
+/*
+ * 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.
+ */
+static long sdbm_hash (char *str, int len)
+{
+    unsigned long n = 0;
+
+#ifdef DUFF
+#define HASHC   n = *str++ + 65599 * n
+    if (len > 0)
+      {
+	  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;
+}
+
+/*
+ * 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.
+ */
+static int chkpage (char *pag)
+{
+    int     n;
+    int     off;
+    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] > off || ino[1] > off ||
+		    ino[1] > ino[0])
+		    return 0;
+		off = ino[1];
+		n -= 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 (char *pag, int n, char *key, int siz)
+{
+    int     i;
+    int     off = PBLKSIZ;
+    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;
+}
+
+#ifdef SEEDUPS
+static int duppair (char *pag, datum key)
+{
+    short  *ino = (short *) pag;
+
+    return ino[0] > 0 && seepair (pag, ino[0], key.dptr, key.dsize) > 0;
+}
+
+#endif
+
+/* ************************* */
+
+/*
+ * 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: public domain.
+ *
+ * page-level routines
+ */
+
+/*
+ * 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.
+ */
+
+static int fitpair (char *pag, int need)
+{
+    int     n;
+    int     off;
+    int     avail;
+    short  *ino = (short *) pag;
+
+    off = ((n = ino[0]) > 0) ? ino[n] : PBLKSIZ;
+    avail = off - (n + 1) * sizeof (short);
+    need += 2 * sizeof (short);
+
+    return need <= avail;
+}
+
+static void putpair (char *pag, datum key, datum val)
+{
+    int     n;
+    int     off;
+    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;
+}
+
+static datum getpair (char *pag, datum key)
+{
+    int     i;
+    int     n;
+    datum   val;
+    short  *ino = (short *) pag;
+
+    if ((n = ino[0]) == 0)
+	return nullitem;
+
+    if ((i = seepair (pag, n, key.dptr, key.dsize)) == 0)
+	return nullitem;
+
+    val.dptr = pag + ino[i + 1];
+    val.dsize = ino[i] - ino[i + 1];
+    return val;
+}
+
+static datum getnkey (char *pag, int num)
+{
+    datum   key;
+    int     off;
+    short  *ino = (short *) pag;
+
+    num = num * 2 - 1;
+    if (ino[0] == 0 || num > ino[0])
+	return nullitem;
+
+    off = (num > 1) ? ino[num - 1] : PBLKSIZ;
+
+    key.dptr = pag + ino[num];
+    key.dsize = off - ino[num];
+
+    return key;
+}
+
+static int delpair (char *pag, datum key)
+{
+    int     n;
+    int     i;
+    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)
+      {
+	  int     m;
+	  char   *dst = pag + (i == 1 ? PBLKSIZ : ino[i - 1]);
+	  char   *src = pag + ino[i + 1];
+	  int     zoo = dst - src;
+
+/*
+ * shift data/keys down
+ */
+	  m = ino[i + 1] - ino[n];
+#ifdef DUFF
+#define MOVB    *--dst = *--src
+	  if (m > 0)
+	    {
+		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;
+}
+
+static void splpage (char *pag, char *new, long sbit)
+{
+    datum   key;
+    datum   val;
+
+    int     n;
+    int     off = PBLKSIZ;
+    char    cur[PBLKSIZ];
+    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;
+      }
+}
+
+static int getdbit (DBM * db, long dbit)
+{
+    long    c;
+    long    dirb;
+
+    c = dbit / BYTESIZ;
+    dirb = c / DBLKSIZ;
+
+    if (dirb != db->dirbno)
+      {
+	  int got;
+	  if (lseek (db->dirf, OFF_DIR (dirb), SEEK_SET) < 0
+	      || (got = read(db->dirf, db->dirbuf, DBLKSIZ)) < 0)
+	      return 0;
+	  if (got==0)
+              memset(db->dirbuf,0,DBLKSIZ);
+	  db->dirbno = dirb;
+      }
+
+    return db->dirbuf[c % DBLKSIZ] & (1 << dbit % BYTESIZ);
+}
+
+static int setdbit (DBM * db, long dbit)
+{
+    long    c;
+    long    dirb;
+
+    c = dbit / BYTESIZ;
+    dirb = c / DBLKSIZ;
+
+    if (dirb != db->dirbno)
+      {
+	  int got;
+	  if (lseek (db->dirf, OFF_DIR (dirb), SEEK_SET) < 0
+	      || (got = read(db->dirf, db->dirbuf, DBLKSIZ)) < 0)
+	      return 0;
+	  if (got==0)
+              memset(db->dirbuf,0,DBLKSIZ);
+	  db->dirbno = dirb;
+      }
+
+    db->dirbuf[c % DBLKSIZ] |= (1 << dbit % BYTESIZ);
+
+#if 0
+    if (dbit >= db->maxbno)
+	db->maxbno += DBLKSIZ * BYTESIZ;
+#else
+    if (OFF_DIR((dirb+1))*BYTESIZ > db->maxbno)
+        db->maxbno=OFF_DIR((dirb+1))*BYTESIZ;
+#endif
+
+    if (lseek (db->dirf, OFF_DIR (dirb), SEEK_SET) < 0
+	|| write (db->dirf, db->dirbuf, DBLKSIZ) < 0)
+	return 0;
+
+    return 1;
+}
+
+/*
+ * getnext - get the next key in the page, and if done with
+ * the page, try the next page in sequence
+ */
+static datum getnext (DBM * db)
+{
+    datum   key;
+
+    for (;;)
+      {
+	  db->keyptr++;
+	  key = getnkey (db->pagbuf, db->keyptr);
+	  if (key.dptr != NULL)
+	      return key;
+/*
+ * 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->keyptr = 0;
+	  if (db->pagbno != db->blkptr++)
+	      if (lseek (db->pagf, OFF_PAG (db->blkptr), SEEK_SET) < 0)
+		  break;
+	  db->pagbno = db->blkptr;
+	  if (read (db->pagf, db->pagbuf, PBLKSIZ) <= 0)
+	      break;
+	  if (!chkpage (db->pagbuf))
+	      break;
+      }
+
+    return ioerr (db), nullitem;
+}
+
+/*
+ * all important binary trie traversal
+ */
+static int getpage (DBM * db, long hash)
+{
+    int     hbit;
+    long    dbit;
+    long    pagb;
+
+    dbit = 0;
+    hbit = 0;
+    while (dbit < db->maxbno && getdbit (db, dbit))
+	dbit = 2 * dbit + ((hash & (1 << hbit++)) ? 2 : 1);
+
+    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.
+ */
+	  if (lseek (db->pagf, OFF_PAG (pagb), SEEK_SET) < 0
+	      || read (db->pagf, db->pagbuf, PBLKSIZ) < 0)
+	      return 0;
+	  if (!chkpage (db->pagbuf))
+	      return 0;
+	  db->pagbno = pagb;
+      }
+    return 1;
+}
+
+/*
+ * makroom - make room by splitting the overfull page
+ * this routine will attempt to make room for SPLTMAX times before
+ * giving up.
+ */
+static int makroom (DBM * db, long hash, int need)
+{
+    long    newp;
+    char    twin[PBLKSIZ];
+    char   *pag = db->pagbuf;
+    char   *new = twin;
+    int     smax = SPLTMAX;
+
+    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 (lseek (db->pagf, OFF_PAG (db->pagbno), SEEK_SET) < 0
+		    || write (db->pagf, db->pagbuf, PBLKSIZ) < 0)
+		    return 0;
+		db->pagbno = newp;
+		(void) memcpy (pag, new, PBLKSIZ);
+	    }
+	  else if (lseek (db->pagf, OFF_PAG (newp), SEEK_SET) < 0
+		   || write (db->pagf, new, PBLKSIZ) < 0)
+	      return 0;
+
+	  if (!setdbit (db, db->curbit))
+	      return 0;
+/*
+ * see if we have enough room now
+ */
+	  if (fitpair (pag, need))
+	      return 1;
+/*
+ * 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 (lseek (db->pagf, OFF_PAG (db->pagbno), SEEK_SET) < 0
+	      || write (db->pagf, db->pagbuf, PBLKSIZ) < 0)
+	      return 0;
+
+      }
+    while (--smax);
+/*
+ * if we are here, this is real bad news. After SPLTMAX splits,
+ * we still cannot fit the key. say goodnight.
+ */
+#ifdef BADMESS
+    (void) write (2, "sdbm: cannot insert after SPLTMAX attempts.\n", 44);
+#endif
+    return 0;
+
+}
+
+static SDBM *sdbm_prep (char *dirname, char *pagname, int flags, int mode)
+{
+    SDBM   *db;
+    struct stat dstat;
+
+    if ((db = (SDBM *) mymalloc (sizeof (SDBM))) == NULL)
+	return errno = ENOMEM, (SDBM *) NULL;
+
+    db->flags = 0;
+    db->blkptr = 0;
+    db->keyptr = 0;
+/*
+ * adjust user flags so that WRONLY becomes RDWR,
+ * as required by this package. Also set our internal
+ * flag for RDONLY if needed.
+ */
+    if (flags & O_WRONLY)
+	flags = (flags & ~O_WRONLY) | O_RDWR;
+    else if ((flags & 03) == O_RDONLY)
+	db->flags = DBM_RDONLY;
+#if defined(OS2) || defined(MSDOS) || defined(WIN32)
+    flags |= O_BINARY;
+#endif
+
+/*
+ * Make sure to ignore the O_EXCL option, as the file might exist due
+ * to the locking.
+ */
+    flags &= ~O_EXCL;
+
+/*
+ * open the files in sequence, and stat the dirfile.
+ * If we fail anywhere, undo everything, return NULL.
+ */
+
+    if ((db->pagf = open (pagname, flags, mode)) > -1)
+      {
+	  if ((db->dirf = open (dirname, flags, mode)) > -1)
+	    {
+/*
+ * need the dirfile size to establish max bit number.
+ */
+		if (fstat (db->dirf, &dstat) == 0)
+		  {
+		      /*
+                       * success
+                       */
+		      return db;
+		  }
+		msg_info ("closing dirf");
+		(void) close (db->dirf);
+	    }
+	  msg_info ("closing pagf");
+	  (void) close (db->pagf);
+      }
+    myfree ((char *) db);
+    return (SDBM *) NULL;
+}
+
+static DBM *sdbm_internal_open (SDBM * sdbm)
+{
+    DBM    *db;
+    struct stat dstat;
+
+    if ((db = (DBM *) mymalloc (sizeof (DBM))) == NULL)
+	return errno = ENOMEM, (DBM *) NULL;
+
+    db->flags = sdbm->flags;
+    db->hmask = 0;
+    db->blkptr = sdbm->blkptr;
+    db->keyptr = sdbm->keyptr;
+    db->pagf = sdbm->pagf;
+    db->dirf = sdbm->dirf;
+    db->pagbuf = sdbm->pagbuf;
+    db->dirbuf = sdbm->dirbuf;
+
+/*
+ * need the dirfile size to establish max bit number.
+ */
+    if (fstat (db->dirf, &dstat) == 0)
+      {
+/*
+ * zero size: either a fresh database, or one with a single,
+ * unsplit data page: dirpage is all zeros.
+ */
+	  db->dirbno = (!dstat.st_size) ? 0 : -1;
+	  db->pagbno = -1;
+	  db->maxbno = dstat.st_size * BYTESIZ;
+
+	  (void) memset (db->pagbuf, 0, PBLKSIZ);
+	  (void) memset (db->dirbuf, 0, DBLKSIZ);
+	  return db;
+      }
+    myfree ((char *) db);
+    return (DBM *) NULL;
+}
+
+static void sdbm_internal_close (DBM * db)
+{
+    if (db == NULL)
+	errno = EINVAL;
+    else
+      {
+	  myfree ((char *) db);
+      }
+}
+
+datum   sdbm_fetch (SDBM * sdb, datum key)
+{
+    datum   retval;
+    DBM    *db;
+
+    if (sdb == NULL || bad (key))
+	return errno = EINVAL, nullitem;
+
+    if (!(db = sdbm_internal_open (sdb)))
+	return errno = EINVAL, nullitem;
+
+    if (getpage (db, exhash (key)))
+      {
+	  retval = getpair (db->pagbuf, key);
+	  sdbm_internal_close (db);
+	  return retval;
+      }
+
+    sdbm_internal_close (db);
+
+    return ioerr (sdb), nullitem;
+}
+
+int     sdbm_delete (SDBM * sdb, datum key)
+{
+    int     retval;
+    DBM    *db;
+
+    if (sdb == NULL || bad (key))
+	return errno = EINVAL, -1;
+    if (sdbm_rdonly (sdb))
+	return errno = EPERM, -1;
+
+    if (!(db = sdbm_internal_open (sdb)))
+	return errno = EINVAL, -1;
+
+    if (getpage (db, exhash (key)))
+      {
+	  if (!delpair (db->pagbuf, key))
+	      retval = -1;
+/*
+ * update the page file
+ */
+	  else if (lseek (db->pagf, OFF_PAG (db->pagbno), SEEK_SET) < 0
+		   || write (db->pagf, db->pagbuf, PBLKSIZ) < 0)
+	      retval = ioerr (sdb), -1;
+	  else
+	      retval = 0;
+      }
+    else
+	retval = ioerr (sdb), -1;
+
+    sdbm_internal_close (db);
+
+    return retval;
+}
+
+int     sdbm_store (SDBM * sdb, datum key, datum val, int flags)
+{
+    int     need;
+    int     retval;
+    long    hash;
+    DBM    *db;
+
+    if (sdb == NULL || bad (key))
+	return errno = EINVAL, -1;
+    if (sdbm_rdonly (sdb))
+	return errno = EPERM, -1;
+
+    need = key.dsize + val.dsize;
+/*
+ * is the pair too big (or too small) for this database ??
+ */
+    if (need < 0 || need > PAIRMAX)
+	return errno = EINVAL, -1;
+
+    if (!(db = sdbm_internal_open (sdb)))
+	return errno = EINVAL, -1;
+
+    if (getpage (db, (hash = exhash (key))))
+      {
+/*
+ * if we need to replace, delete the key/data pair
+ * first. If it is not there, ignore.
+ */
+	  if (flags == DBM_REPLACE)
+	      (void) delpair (db->pagbuf, key);
+#ifdef SEEDUPS
+	  else if (duppair (db->pagbuf, key))
+	    {
+		sdbm_internal_close (db);
+		return 1;
+	    }
+#endif
+/*
+ * if we do not have enough room, we have to split.
+ */
+	  if (!fitpair (db->pagbuf, need))
+	      if (!makroom (db, hash, need))
+		{
+		    sdbm_internal_close (db);
+		    return ioerr (db), -1;
+		}
+/*
+ * we have enough room or split is successful. insert the key,
+ * and update the page file.
+ */
+	  (void) putpair (db->pagbuf, key, val);
+
+	  if (lseek (db->pagf, OFF_PAG (db->pagbno), SEEK_SET) < 0
+	      || write (db->pagf, db->pagbuf, PBLKSIZ) < 0)
+	    {
+		sdbm_internal_close (db);
+		return ioerr (db), -1;
+	    }
+	  /*
+           * success
+           */
+	  sdbm_internal_close (db);
+	  return 0;
+      }
+
+    sdbm_internal_close (db);
+    return ioerr (sdb), -1;
+}
+
+/*
+ * the following two routines will break if
+ * deletions aren't taken into account. (ndbm bug)
+ */
+datum   sdbm_firstkey (SDBM * sdb)
+{
+    datum   retval;
+    DBM    *db;
+
+    if (sdb == NULL)
+	return errno = EINVAL, nullitem;
+
+    if (!(db = sdbm_internal_open (sdb)))
+	return errno = EINVAL, nullitem;
+
+/*
+ * start at page 0
+ */
+    if (lseek (db->pagf, OFF_PAG (0), SEEK_SET) < 0
+	|| read (db->pagf, db->pagbuf, PBLKSIZ) < 0)
+      {
+	  sdbm_internal_close (db);
+	  return ioerr (sdb), nullitem;
+      }
+    db->pagbno = 0;
+    db->blkptr = 0;
+    db->keyptr = 0;
+
+    retval = getnext (db);
+    sdb->blkptr = db->blkptr;
+    sdb->keyptr = db->keyptr;
+    sdbm_internal_close (db);
+    return retval;
+}
+
+datum   sdbm_nextkey (SDBM * sdb)
+{
+    datum   retval;
+    DBM    *db;
+
+    if (sdb == NULL)
+	return errno = EINVAL, nullitem;
+
+    if (!(db = sdbm_internal_open (sdb)))
+	return errno = EINVAL, nullitem;
+
+    retval = getnext (db);
+    sdb->blkptr = db->blkptr;
+    sdb->keyptr = db->keyptr;
+    sdbm_internal_close (db);
+    return retval;
+}
+
+void    sdbm_close (SDBM * db)
+{
+    if (db == NULL)
+	errno = EINVAL;
+    else
+      {
+	  (void) close (db->dirf);
+	  (void) close (db->pagf);
+	  myfree ((char *) db);
+      }
+}
+
+SDBM   *sdbm_open (char *file, int flags, int mode)
+{
+    SDBM   *db;
+    char   *dirname;
+    char   *pagname;
+    int     n;
+
+    if (file == NULL || !*file)
+	return errno = EINVAL, (SDBM *) NULL;
+/*
+ * need space for two seperate filenames
+ */
+    n = strlen (file) * 2 + strlen (DIRFEXT) + strlen (PAGFEXT) + 2;
+
+    if ((dirname = (char *) mymalloc ((unsigned) n)) == NULL)
+	return errno = ENOMEM, (SDBM *) NULL;
+/*
+ * build the file names
+ */
+    dirname = strcat (strcpy (dirname, file), DIRFEXT);
+    pagname = strcpy (dirname + strlen (dirname) + 1, file);
+    pagname = strcat (pagname, PAGFEXT);
+
+    db = sdbm_prep (dirname, pagname, flags, mode);
+    myfree ((char *) dirname);
+    return db;
+}
+
Index: src/util/sdbm.h
===================================================================
--- /dev/null
+++ src/util/sdbm.h
@@ -0,0 +1,97 @@
+/*++
+/* NAME
+/*      sdbm 3h
+/* SUMMARY
+/*      SDBM Simple DBM: ndbm work-alike hashed database library
+/* SYNOPSIS
+/*      include "sdbm.h"
+/* DESCRIPTION
+/* .nf
+/*--*/
+
+#ifndef UTIL_SDBM_H
+#define UTIL_SDBM_H
+
+/*
+ * sdbm - ndbm work-alike hashed database library
+ * based on Per-Ake Larson's Dynamic Hashing algorithms. BIT 18 (1978).
+ * author: oz@nexus.yorku.ca
+ * status: public domain.
+ */
+
+#define DUFF    /* go ahead and use the loop-unrolled version */
+
+#include <stdio.h>
+
+#define DBLKSIZ 16384                   /* SSL cert chains require more */
+#define PBLKSIZ 8192                    /* SSL cert chains require more */
+#define PAIRMAX 8008                    /* arbitrary on PBLKSIZ-N */
+#define SPLTMAX 10                      /* maximum allowed splits */
+                                        /* for a single insertion */
+#define DIRFEXT ".dir"
+#define PAGFEXT ".pag"
+
+typedef struct {
+        int dirf;                      /* directory file descriptor */
+        int pagf;                      /* page file descriptor */
+        int flags;                     /* status/error flags, see below */
+        long blkptr;                   /* current block for nextkey */
+        int keyptr;                    /* current key for nextkey */
+        char pagbuf[PBLKSIZ];          /* page file block buffer */
+        char dirbuf[DBLKSIZ];          /* directory file block buffer */
+} SDBM;
+
+#define DBM_RDONLY      0x1            /* data base open read-only */
+#define DBM_IOERR       0x2            /* data base I/O error */
+
+/*
+ * utility macros
+ */
+#define sdbm_rdonly(db)         ((db)->flags & DBM_RDONLY)
+#define sdbm_error(db)          ((db)->flags & DBM_IOERR)
+
+#define sdbm_clearerr(db)       ((db)->flags &= ~DBM_IOERR)  /* ouch */
+
+#define sdbm_dirfno(db) ((db)->dirf)
+#define sdbm_pagfno(db) ((db)->pagf)
+
+typedef struct {
+        char *dptr;
+        int dsize;
+} datum;
+
+extern datum nullitem;
+
+/*
+ * flags to sdbm_store
+ */
+#define DBM_INSERT      0
+#define DBM_REPLACE     1
+
+/*
+ * ndbm interface
+ */
+extern SDBM *sdbm_open(char *, int, int);
+extern void sdbm_close(SDBM *);
+extern datum sdbm_fetch(SDBM *, datum);
+extern int sdbm_delete(SDBM *, datum);
+extern int sdbm_store(SDBM *, datum, datum, int);
+extern datum sdbm_firstkey(SDBM *);
+extern datum sdbm_nextkey(SDBM *);
+
+/*
+ * sdbm - ndbm work-alike hashed database library
+ * tuning and portability constructs [not nearly enough]
+ * author: oz@nexus.yorku.ca
+ */
+
+#define BYTESIZ         8
+
+/*
+ * important tuning parms (hah)
+ */
+
+#define SEEDUPS                 /* always detect duplicates */
+#define BADMESS                 /* generate a message for worst case:
+                                   cannot make room after SPLTMAX splits */
+#endif /* UTIL_SDBM_H */
Index: src/util/sys_defs.h
===================================================================
--- src/util/sys_defs.h.orig
+++ src/util/sys_defs.h
@@ -755,6 +755,7 @@ extern int initgroups(const char *, int)
 #define INTERNAL_LOCK	MYFLOCK_STYLE_FLOCK
 #define DEF_MAILBOX_LOCK "fcntl, dotlock"	/* RedHat >= 4.x */
 #define HAS_FSYNC
+#define HAS_SDBM
 #define HAS_DB
 #define DEF_DB_TYPE	"hash"
 #define ALIAS_DB_MAP	"hash:/etc/aliases"
@@ -768,11 +769,25 @@ extern int initgroups(const char *, int)
 #define STATFS_IN_SYS_VFS_H
 #define PREPEND_PLUS_TO_OPTSTRING
 #define HAS_POSIX_REGEXP
+#define HAS_DLOPEN
 #define NATIVE_SENDMAIL_PATH "/usr/sbin/sendmail"
 #define NATIVE_MAILQ_PATH "/usr/bin/mailq"
 #define NATIVE_NEWALIAS_PATH "/usr/bin/newaliases"
 #define NATIVE_COMMAND_DIR "/usr/sbin"
+#ifdef DEBIAN
+#define NATIVE_DAEMON_DIR      "/usr/lib/postfix"
+#ifndef DEF_MANPAGE_DIR
+#define DEF_MANPAGE_DIR                "/usr/share/man"
+#endif
+#ifndef DEF_SAMPLE_DIR
+#define DEF_SAMPLE_DIR         "/usr/share/doc/postfix/examples"
+#endif
+#ifndef DEF_README_DIR
+#define DEF_README_DIR         "/usr/share/doc/postfix"
+#endif
+#else
 #define NATIVE_DAEMON_DIR "/usr/libexec/postfix"
+#endif
 #ifdef __GLIBC_PREREQ
 # define HAVE_GLIBC_API_VERSION_SUPPORT(maj, min) __GLIBC_PREREQ(maj, min)
 #else
@@ -954,6 +969,7 @@ extern int h_errno;			/* <netdb.h> impor
 #define USE_STATFS
 #define STATFS_IN_SYS_VFS_H
 #define HAS_POSIX_REGEXP
+#define HAS_DLOPEN
 #define NATIVE_SENDMAIL_PATH "/usr/sbin/sendmail"
 #define NATIVE_MAILQ_PATH "/usr/bin/mailq"
 #define NATIVE_NEWALIAS_PATH "/usr/bin/newaliases"
@@ -993,6 +1009,7 @@ extern int h_errno;			/* <netdb.h> impor
 #define USE_STATFS
 #define STATFS_IN_SYS_VFS_H
 #define HAS_POSIX_REGEXP
+#define HAS_SHL_LOAD
 #define NATIVE_SENDMAIL_PATH "/usr/sbin/sendmail"
 #define NATIVE_MAILQ_PATH "/usr/bin/mailq"
 #define NATIVE_NEWALIAS_PATH "/usr/bin/newaliases"
@@ -1034,6 +1051,7 @@ extern int h_errno;
 #define USE_STATFS
 #define STATFS_IN_SYS_VFS_H
 #define HAS_POSIX_REGEXP
+#define HAS_SHL_LOAD
 #define NATIVE_SENDMAIL_PATH "/usr/bin/sendmail"
 #define NATIVE_MAILQ_PATH "/usr/bin/mailq"
 #define NATIVE_NEWALIAS_PATH "/usr/bin/newaliases"