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-rw-r--r--compat/dbmopen.c125
1 files changed, 125 insertions, 0 deletions
diff --git a/compat/dbmopen.c b/compat/dbmopen.c
new file mode 100644
index 0000000..257da77
--- /dev/null
+++ b/compat/dbmopen.c
@@ -0,0 +1,125 @@
+/* dbmopen.c - Open the file for dbm operations. This looks like the
+ NDBM interface for dbm use. */
+
+/* This file is part of GDBM, the GNU data base manager.
+ Copyright (C) 1990, 1991, 1993, 2007 Free Software Foundation, Inc.
+
+ This program is free software; you can redistribute it and/or modify
+ it under the terms of the GNU General Public License as published by
+ the Free Software Foundation; either version 3, or (at your option)
+ any later version.
+
+ This program is distributed in the hope that it will be useful,
+ but WITHOUT ANY WARRANTY; without even the implied warranty of
+ MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ GNU General Public License for more details.
+
+ You should have received a copy of the GNU General Public License
+ along with this program; if not, write to the Free Software Foundation,
+ Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA. */
+
+/* Include system configuration before all else. */
+#include "autoconf.h"
+
+#include "gdbmdefs.h"
+#include "gdbmerrno.h"
+#include "extern.h"
+
+/* Initialize ndbm system. FILE is a pointer to the file name. In
+ standard dbm, the database is found in files called FILE.pag and
+ FILE.dir. To make gdbm compatable with dbm using the dbminit call,
+ the same file names are used. Specifically, dbminit will use the file
+ name FILE.pag in its call to gdbm open. If the file (FILE.pag) has a
+ size of zero bytes, a file initialization procedure is performed,
+ setting up the initial structure in the file. Any error detected will
+ cause a return value of -1. No errors cause the return value of 0.
+ NOTE: file.dir will be ignored and will always have a size of zero.
+ FLAGS and MODE are the same as the open (2) call. This call will
+ look at the FLAGS and decide what call to make to gdbm_open. For
+ FLAGS == O_RDONLY, it will be a GDBM_READER, if FLAGS == O_RDWR|O_CREAT,
+ it will be a GDBM_WRCREAT (creater and writer) and if the FLAGS == O_RDWR,
+ it will be a GDBM_WRITER and if FLAGS contain O_TRUNC then it will be
+ a GDBM_NEWDB. All other values of FLAGS in the flags are
+ ignored. */
+
+gdbm_file_info *
+dbm_open (char *file, int flags, int mode)
+{
+ char* pag_file; /* Used to construct "file.pag". */
+ char* dir_file; /* Used to construct "file.dir". */
+ struct stat dir_stat; /* Stat information for "file.dir". */
+ gdbm_file_info *temp_dbf; /* Temporary file pointer storage. */
+
+
+ /* Prepare the correct names of "file.pag" and "file.dir". */
+ pag_file = (char *) malloc (strlen (file)+5);
+ dir_file = (char *) malloc (strlen (file)+5);
+ if ((pag_file == NULL) || (dir_file == NULL))
+ {
+ gdbm_errno = GDBM_MALLOC_ERROR; /* For the hell of it. */
+ return NULL;
+ }
+
+ strcpy (pag_file, file);
+ strcat (pag_file, ".pag");
+ strcpy (dir_file, file);
+ strcat (dir_file, ".dir");
+
+
+ /* Call the actual routine, saving the pointer to the file information. */
+ flags &= O_RDONLY | O_RDWR | O_CREAT | O_TRUNC;
+ if (flags == O_RDONLY)
+ {
+ temp_dbf = gdbm_open (pag_file, 0, GDBM_READER, 0, NULL);
+ }
+ else if (flags == (O_RDWR | O_CREAT))
+ {
+ temp_dbf = gdbm_open (pag_file, 0, GDBM_WRCREAT, mode, NULL);
+ }
+ else if ( (flags & O_TRUNC) == O_TRUNC)
+ {
+ temp_dbf = gdbm_open (pag_file, 0, GDBM_NEWDB, mode, NULL);
+ }
+ else
+ {
+ temp_dbf = gdbm_open (pag_file, 0, GDBM_WRITER, 0, NULL);
+ }
+
+ /* Did we successfully open the file? */
+ if (temp_dbf == NULL)
+ {
+ gdbm_errno = GDBM_FILE_OPEN_ERROR;
+ goto done;
+ }
+
+ /* If the database is new, link "file.dir" to "file.pag". This is done
+ so the time stamp on both files is the same. */
+ if (stat (dir_file, &dir_stat) == 0)
+ {
+ if (dir_stat.st_size == 0)
+ if (unlink (dir_file) != 0 || link (pag_file, dir_file) != 0)
+ {
+ gdbm_errno = GDBM_FILE_OPEN_ERROR;
+ gdbm_close (temp_dbf);
+ temp_dbf = NULL;
+ goto done;
+ }
+ }
+ else
+ {
+ /* Since we can't stat it, we assume it is not there and try
+ to link the dir_file to the pag_file. */
+ if (link (pag_file, dir_file) != 0)
+ {
+ gdbm_errno = GDBM_FILE_OPEN_ERROR;
+ gdbm_close (temp_dbf);
+ temp_dbf = NULL;
+ goto done;
+ }
+ }
+
+done:
+ free (pag_file);
+ free (dir_file);
+ return temp_dbf;
+}

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