1 files changed, 57 insertions, 0 deletions
diff --git a/common/error.c b/common/error.c
new file mode 100644
index 0000000..7b46826
--- /dev/null
+++ b/common/error.c
@@ -0,0 +1,57 @@
+/*
+ * Copyright (C) 2023  Patrick McDermott
+ *
+ * This file is part of opkg-opk.
+ *
+ * opkg-opk 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 of the License, or
+ * (at your option) any later version.
+ *
+ * opkg-opk 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 opkg-opk.  If not, see <https://www.gnu.org/licenses/>.
+ */
+
+#include <errno.h>
+#include <stdarg.h>
+#include <stdio.h>
+#include <string.h>
+
+#include "error.h"
+
+static const char *_opkg_opk_program_name;
+
+void
+opkg_opk_set_program_name(const char *program_name)
+{
+	_opkg_opk_program_name = program_name;
+}
+
+void __attribute__((format(__printf__, 1, 2)))
+opkg_opk_error(const char *fmt, ...)
+{
+	va_list ap;
+
+	fprintf(stderr, "%s: ", _opkg_opk_program_name);
+	va_start(ap, fmt);
+	vfprintf(stderr, fmt, ap);
+	va_end(ap);
+	fputc('\n', stderr);
+}
+
+void __attribute__((format(__printf__, 1, 2)))
+opkg_opk_errno(const char *fmt, ...)
+{
+	va_list ap;
+
+	fprintf(stderr, "%s: ", _opkg_opk_program_name);
+	va_start(ap, fmt);
+	vfprintf(stderr, fmt, ap);
+	va_end(ap);
+	fprintf(stderr, ": %s\n", strerror(errno));
+}