1 files changed, 49 insertions, 0 deletions
diff --git a/libsframe/sframe-error.c b/libsframe/sframe-error.c
new file mode 100644
index 0000000..9dc2321
--- /dev/null
+++ b/libsframe/sframe-error.c
@@ -0,0 +1,49 @@
+/* sframe-error.c - Error messages.
+
+   Copyright (C) 2022 Free Software Foundation, Inc.
+
+   This file is part of libsframe.
+
+   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 of the License, 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, see <http://www.gnu.org/licenses/>.  */
+
+#include "sframe-api.h"
+#include <stddef.h>
+#include <string.h>
+
+/* In this file, we want to treat the first item of the SFrame error
+   macro like subsequent items.  */
+#define _SFRAME_FIRST(NAME, VALUE) _SFRAME_ITEM(NAME, VALUE)
+
+/* The error message strings, each in a unique structure member precisely big
+   enough for that error, plus a str member to access them all as a string
+   table.  */
+
+static const char *const _sframe_errlist[] = {
+#define _SFRAME_ITEM(n, s) s,
+_SFRAME_ERRORS
+#undef _SFRAME_ITEM
+};
+
+const char *
+sframe_errmsg (int error)
+{
+  const char *str;
+
+  if (error >= SFRAME_ERR_BASE && (error - SFRAME_ERR_BASE) < SFRAME_ERR_NERR)
+    str = _sframe_errlist[error - SFRAME_ERR_BASE];
+  else
+    str = (const char *) strerror (error);
+
+  return (str ? str : "Unknown error");
+}