1 files changed, 58 insertions, 0 deletions
diff --git a/src/dprintf.c b/src/dprintf.c
new file mode 100644
index 0000000..1b29dae
--- /dev/null
+++ b/src/dprintf.c
@@ -0,0 +1,58 @@
+/*
+ * Copyright (c) Ian F. Darwin 1986-1995.
+ * Software written by Ian F. Darwin and others;
+ * maintained 1995-present by Christos Zoulas and others.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ * 1. Redistributions of source code must retain the above copyright
+ *    notice immediately at the beginning of the file, without modification,
+ *    this list of conditions, and the following disclaimer.
+ * 2. Redistributions in binary form must reproduce the above copyright
+ *    notice, this list of conditions and the following disclaimer in the
+ *    documentation and/or other materials provided with the distribution.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
+ * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
+ * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
+ * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE FOR
+ * ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
+ * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
+ * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
+ * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
+ * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
+ * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
+ * SUCH DAMAGE.
+ */
+#include "file.h"
+
+#ifndef	lint
+FILE_RCSID("@(#)$File: dprintf.c,v 1.4 2022/09/24 20:30:13 christos Exp $")
+#endif	/* lint */
+
+#include <assert.h>
+#include <unistd.h>
+#include <stdio.h>
+#include <stdarg.h>
+
+int
+dprintf(int fd, const char *fmt, ...)
+{
+	va_list ap;
+	/* Simpler than using vasprintf() here, since we never need more */
+	char buf[1024];
+	int len;
+
+	va_start(ap, fmt);
+	len = vsnprintf(buf, sizeof(buf), fmt, ap);
+	va_end(ap);
+
+	if ((size_t)len >= sizeof(buf))
+		return -1;
+
+	if (write(fd, buf, (size_t)len) != len)
+		return -1;
+
+	return len;
+}