Add error library.

1 files changed, 22 insertions, 0 deletions

diff --git a/error/include/error.h b/error/include/error.h
new file mode 100644
index 0000000..92c06ff
--- /dev/null
+++ b/error/include/error.h
@@ -0,0 +1,22 @@
+#pragma once
+
+#include <cstring.h>
+#include <stdio.h>
+
+/// Get the last error.
+const char* get_error(void);
+
+extern xlstring gfx_error;
+
+/// Set the last error.
+#define set_error(...) \
+  gfx_error.length = snprintf(gfx_error.str, xlstring_size, __VA_ARGS__)
+
+/// Prepend an error to the last error.
+#define prepend_error(...)                                        \
+  {                                                               \
+    xlstring head;                                                \
+    head.length = snprintf(head.str, xlstring_size, __VA_ARGS__); \
+    xlstring_append(&head, xlstring_make(": "));                  \
+    gfx_error = xlstring_concat(head, gfx_error);                 \
+  }