1 files changed, 116 insertions, 0 deletions
diff --git a/src/global/mkmap_dbm.c b/src/global/mkmap_dbm.c
new file mode 100644
index 0000000..1db588b
--- /dev/null
+++ b/src/global/mkmap_dbm.c
@@ -0,0 +1,116 @@
+/*++
+/* NAME
+/*	mkmap_dbm 3
+/* SUMMARY
+/*	create or open database, DBM style
+/* SYNOPSIS
+/*	#include <mkmap.h>
+/*
+/*	MKMAP	*mkmap_dbm_open(path)
+/*	const char *path;
+/* DESCRIPTION
+/*	This module implements support for creating DBM databases.
+/*
+/*	mkmap_dbm_open() takes a file name, appends the ".dir" and ".pag"
+/*	suffixes, and creates or opens the named DBM database.
+/*	This routine is a DBM-specific helper for the more general
+/*	mkmap_open() routine.
+/*
+/*	All errors are fatal.
+/* SEE ALSO
+/*	dict_dbm(3), DBM dictionary interface.
+/* LICENSE
+/* .ad
+/* .fi
+/*	The Secure Mailer license must be distributed with this software.
+/* AUTHOR(S)
+/*	Wietse Venema
+/*	IBM T.J. Watson Research
+/*	P.O. Box 704
+/*	Yorktown Heights, NY 10598, USA
+/*--*/
+
+/* System library. */
+
+#include <sys_defs.h>
+#include <unistd.h>
+
+/* Utility library. */
+
+#include <msg.h>
+#include <mymalloc.h>
+#include <stringops.h>
+#include <dict.h>
+#include <dict_dbm.h>
+#include <myflock.h>
+
+/* Application-specific. */
+
+#include "mkmap.h"
+
+#ifdef HAS_DBM
+#ifdef PATH_NDBM_H
+#include PATH_NDBM_H
+#else
+#include <ndbm.h>
+#endif
+
+typedef struct MKMAP_DBM {
+    MKMAP   mkmap;			/* parent class */
+    char   *lock_file;			/* path name */
+    int     lock_fd;			/* -1 or open locked file */
+} MKMAP_DBM;
+
+/* mkmap_dbm_after_close - clean up after closing database */
+
+static void mkmap_dbm_after_close(MKMAP *mp)
+{
+    MKMAP_DBM *mkmap = (MKMAP_DBM *) mp;
+
+    if (mkmap->lock_fd >= 0 && close(mkmap->lock_fd) < 0)
+	msg_warn("close %s: %m", mkmap->lock_file);
+    myfree(mkmap->lock_file);
+}
+
+/* mkmap_dbm_open - create or open database */
+
+MKMAP  *mkmap_dbm_open(const char *path)
+{
+    MKMAP_DBM *mkmap = (MKMAP_DBM *) mymalloc(sizeof(*mkmap));
+    char   *pag_file;
+    int     pag_fd;
+
+    /*
+     * Fill in the generic members.
+     */
+    mkmap->lock_file = concatenate(path, ".dir", (char *) 0);
+    mkmap->mkmap.open = dict_dbm_open;
+    mkmap->mkmap.after_open = 0;
+    mkmap->mkmap.after_close = mkmap_dbm_after_close;
+
+    /*
+     * Unfortunately, not all systems support locking on open(), so we open
+     * the .dir and .pag files before truncating them. Keep one file open for
+     * locking.
+     */
+    if ((mkmap->lock_fd = open(mkmap->lock_file, O_CREAT | O_RDWR, 0644)) < 0)
+	msg_fatal("open %s: %m", mkmap->lock_file);
+
+    pag_file = concatenate(path, ".pag", (char *) 0);
+    if ((pag_fd = open(pag_file, O_CREAT | O_RDWR, 0644)) < 0)
+	msg_fatal("open %s: %m", pag_file);
+    if (close(pag_fd))
+	msg_warn("close %s: %m", pag_file);
+    myfree(pag_file);
+
+    /*
+     * Get an exclusive lock - we're going to change the database so we can't
+     * have any spectators.
+     */
+    if (myflock(mkmap->lock_fd, INTERNAL_LOCK, MYFLOCK_OP_EXCLUSIVE) < 0)
+	msg_fatal("lock %s: %m", mkmap->lock_file);
+
+    return (&mkmap->mkmap);
+}
+
+#endif