user/libc: BSD err.h, getprogname()

1 files changed, 36 insertions, 0 deletions

diff --git a/src/user/lib/err.c b/src/user/lib/err.c
new file mode 100644
index 0000000..7684b6d
--- /dev/null
+++ b/src/user/lib/err.c
@@ -0,0 +1,36 @@
+#include <err.h>
+#include <errno.h>
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+
+_Noreturn void err(int ret, const char *fmt, ...) {
+	va_list args;
+	va_start(args, fmt);
+	vwarn(fmt, args);
+	va_end(args);
+	exit(ret);
+}
+
+_Noreturn void errx(int ret, const char *fmt, ...) {
+	va_list args;
+	va_start(args, fmt);
+	vwarnx(fmt, args);
+	va_end(args);
+	exit(ret);
+}
+
+void vwarn(const char *fmt, va_list args) {
+	fprintf(stderr, "%s: ", getprogname());
+	if (fmt) {
+		vfprintf(stderr, fmt, args);
+		fprintf(stderr, ": ");
+	}
+	fprintf(stderr, "%s\n", strerror(errno));
+}
+
+void vwarnx(const char *fmt, va_list args) {
+	fprintf(stderr, "%s: ", getprogname());
+	if (fmt) vfprintf(stderr, fmt, args);
+	fprintf(stderr, "\n");
+}