Initial revision

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;
+}