1 files changed, 60 insertions, 0 deletions
diff --git a/error.c b/error.c
new file mode 100644
index 0000000..2c6e6fb
--- /dev/null
+++ b/error.c
@@ -0,0 +1,60 @@
+/*
+ * error.c: buttress error handling
+ */
+
+#include <stdio.h>
+#include <stdlib.h>
+#include <stdarg.h>
+#include "buttress.h"
+
+/*
+ * Error flags
+ */
+#define PREFIX 0x0001		       /* give `buttress:' prefix */
+
+static void do_error(int code, va_list ap) {
+    char error[1024];
+    char *sp;
+    int flags;
+
+    switch(code) {
+      case err_nomemory:	       /* no arguments */
+	sprintf(error, "out of memory");
+	flags = PREFIX;
+	break;
+      case err_optnoarg:
+	sp = va_arg(ap, char *);
+	sprintf(error, "option `-%.200s' requires an argument", sp);
+	flags = PREFIX;
+	break;
+      case err_nosuchopt:
+	sp = va_arg(ap, char *);
+	sprintf(error, "unrecognised option `-%.200s'", sp);
+	flags = PREFIX;
+	break;
+      case err_noinput:		       /* no arguments */
+	sprintf(error, "no input files");
+	flags = PREFIX;
+	break;
+    }
+
+    if (flags & PREFIX)
+	fputs("buttress: ", stderr);
+    fputs(error, stderr);
+    fputc('\n', stderr);
+}
+
+void fatal(int code, ...) {
+    va_list ap;
+    va_start(ap, code);
+    do_error(code, ap);
+    va_end(ap);
+    exit(EXIT_FAILURE);
+}
+
+void error(int code, ...) {
+    va_list ap;
+    va_start(ap, code);
+    do_error(code, ap);
+    va_end(ap);
+}