libotutil: Establish a place for GPG utilities

Add ot-gpg-utils.[ch] and move _ostree_gpg_error_to_gio_error() here.

src/libotutil/ot-gpg-utils.c

@@ -0,0 +1,57 @@
+/* -*- mode: C; c-file-style: "gnu"; indent-tabs-mode: nil; -*-
+ *
+ * Copyright (C) 2015 Red Hat, Inc.
+ *
+ * This library is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU Lesser General Public
+ * License as published by the Free Software Foundation; either
+ * version 2 of the License, or (at your option) any later version.
+ *
+ * This library 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
+ * Lesser General Public License for more details.
+ *
+ * You should have received a copy of the GNU Lesser General Public
+ * License along with this library; if not, write to the
+ * Free Software Foundation, Inc., 59 Temple Place - Suite 330,
+ * Boston, MA 02111-1307, USA.
+ */
+
+#include "config.h"
+
+#include "ot-gpg-utils.h"
+
+void
+ot_gpgme_error_to_gio_error (gpgme_error_t   gpg_error,
+                             GError        **error)
+{
+  GIOErrorEnum errcode;
+
+  /* XXX This list is incomplete.  Add cases as needed. */
+
+  switch (gpg_error)
+    {
+      /* special case - shouldn't be here */
+      case GPG_ERR_NO_ERROR:
+        g_return_if_reached ();
+
+      /* special case - abort on out-of-memory */
+      case GPG_ERR_ENOMEM:
+        g_error ("%s: %s",
+                 gpgme_strsource (gpg_error),
+                 gpgme_strerror (gpg_error));
+
+      case GPG_ERR_INV_VALUE:
+        errcode = G_IO_ERROR_INVALID_ARGUMENT;
+        break;
+
+      default:
+        errcode = G_IO_ERROR_FAILED;
+        break;
+    }
+
+  g_set_error (error, G_IO_ERROR, errcode, "%s: %s",
+               gpgme_strsource (gpg_error),
+               gpgme_strerror (gpg_error));
+}

src/libotutil/ot-gpg-utils.h

@@ -0,0 +1,30 @@
+/* -*- mode: C; c-file-style: "gnu"; indent-tabs-mode: nil; -*-
+ *
+ * Copyright (C) 2015 Red Hat, Inc.
+ *
+ * This library is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU Lesser General Public
+ * License as published by the Free Software Foundation; either
+ * version 2 of the License, or (at your option) any later version.
+ *
+ * This library 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
+ * Lesser General Public License for more details.
+ *
+ * You should have received a copy of the GNU Lesser General Public
+ * License along with this library; if not, write to the
+ * Free Software Foundation, Inc., 59 Temple Place - Suite 330,
+ * Boston, MA 02111-1307, USA.
+ */
+
+#pragma once
+
+#include <gpgme.h>
+#include <gio/gio.h>
+
+G_BEGIN_DECLS
+
+void ot_gpgme_error_to_gio_error (gpgme_error_t gpg_error, GError **error);
+
+G_END_DECLS

src/libotutil/otutil.h

@@ -46,5 +46,6 @@
 #include <ot-variant-utils.h>
 #include <ot-spawn-utils.h>
 #include <ot-checksum-utils.h>
+#include <ot-gpg-utils.h>
 
 void ot_ptrarray_add_many (GPtrArray  *a, ...) G_GNUC_NULL_TERMINATED;