Pathnames detection generalized, no longer 'configuration' specific.

[udpgate.git] / src / pathname.c

diff --git a/src/pathname.c b/src/pathname.c
new file mode 100644 (file)
index 0000000..fe4fd18
--- /dev/null
+++ b/src/pathname.c
@@ -0,0 +1,109 @@
+/* $Id$
+ * UDP Gateway persistent configuration pathname detection
+ * Copyright (C) 2005 Jan Kratochvil <project-udpgate@jankratochvil.net>
+ * 
+ * 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; exactly version 2 of June 1991 is required
+ * 
+ * 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., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
+ */
+
+
+#include "config.h"
+
+#include <glib/gmessages.h>
+#include <glib/gmem.h>
+#include <glib/gstrfuncs.h>
+#include <glib/gutils.h>
+#include <unistd.h>
+#include <errno.h>
+#include <stdarg.h>
+
+#include "pathname.h"  /* self */
+
+
+/* OK, GConf would be nice.
+ * Unfortunately the fully-static build does not support GConf process spawn at
+ * all. Also /etc/sysconfig directory is standard for the daemon services.
+ */
+
+
+static gboolean verbose=FALSE;
+
+
+static gboolean try_pairname(const gchar **static_pathname_pointer,const gchar *dirname,const gchar *filename)
+{
+gchar *pathname;
+
+       g_return_val_if_fail(static_pathname_pointer!=NULL,FALSE);
+       g_return_val_if_fail(*static_pathname_pointer==NULL,FALSE);
+       g_return_val_if_fail(dirname!=NULL,FALSE);
+       g_return_val_if_fail(filename!=NULL,FALSE);
+
+       if (access(dirname,W_OK|X_OK)) {
+               if (verbose)
+                       g_warning(_("Directory not accessible(X) and/or writable(W): %s"),dirname);
+               return FALSE;
+               }
+       pathname=g_strdup_printf("%s/%s",dirname,filename);
+       if (access(pathname,R_OK|W_OK) && errno!=ENOENT) {
+               if (verbose)
+                       g_warning(_("Pathname not readable(R) and/or writable(W): %s"),pathname);
+               g_free(pathname);
+               return FALSE;
+               }
+       *static_pathname_pointer=pathname;
+       return TRUE;
+}
+
+G_CONST_RETURN gchar *vpathname_find(const gchar **static_pathname_pointer,va_list ap)
+{
+       g_return_val_if_fail(static_pathname_pointer!=NULL,NULL);
+
+       if (!*static_pathname_pointer) {
+const char *dirname,*filename;
+va_list ap_copy;
+
+               G_VA_COPY(ap_copy,ap);
+retry:
+               while ((dirname=va_arg(ap,const char *))) {
+                       filename=va_arg(ap,const char *);
+                       g_assert(filename!=NULL);
+                       /* Succeeded? */
+                       if (try_pairname(static_pathname_pointer,dirname,filename))
+                               break;
+                       }
+               if (!*static_pathname_pointer && !verbose) {
+                       verbose=TRUE;
+                       G_VA_COPY(ap,ap_copy);
+                       goto retry;
+                       }
+               if (!*static_pathname_pointer) {
+                       g_warning(_("All automatic pathnames failed."));
+                       *static_pathname_pointer="";
+                       }
+               }
+       g_assert(*static_pathname_pointer!=NULL);
+       return *static_pathname_pointer;
+}
+
+G_CONST_RETURN gchar *pathname_find(const gchar **static_pathname_pointer,...)
+{
+const gchar *r;
+va_list ap;
+
+       g_return_val_if_fail(static_pathname_pointer!=NULL,NULL);
+
+       va_start(ap,static_pathname_pointer);
+       r=vpathname_find(static_pathname_pointer,ap);
+       va_end(ap);
+       return r;
+}