Adding upstream version 1:4.17.4.

Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>

lib/string/sprintf/snprintf.h

@@ -0,0 +1,62 @@
+// SPDX-FileCopyrightText: 2023-2024, Alejandro Colomar <alx@kernel.org>
+// SPDX-License-Identifier: BSD-3-Clause
+
+
+#ifndef SHADOW_INCLUDE_LIB_STRING_SPRINTF_SNPRINTF_H_
+#define SHADOW_INCLUDE_LIB_STRING_SPRINTF_SNPRINTF_H_
+
+
+#include <config.h>
+
+#include <stdarg.h>
+#include <stddef.h>
+#include <stdio.h>
+
+#include "attr.h"
+#include "sizeof.h"
+
+
+#define SNPRINTF(s, fmt, ...)                                                 \
+(                                                                             \
+	snprintf_(s, NITEMS(s), fmt __VA_OPT__(,) __VA_ARGS__)                \
+)
+
+
+format_attr(printf, 3, 4)
+inline int snprintf_(char *restrict s, size_t size, const char *restrict fmt,
+    ...);
+format_attr(printf, 3, 0)
+inline int vsnprintf_(char *restrict s, size_t size, const char *restrict fmt,
+    va_list ap);
+
+
+inline int
+snprintf_(char *restrict s, size_t size, const char *restrict fmt, ...)
+{
+	int      len;
+	va_list  ap;
+
+	va_start(ap, fmt);
+	len = vsnprintf_(s, size, fmt, ap);
+	va_end(ap);
+
+	return len;
+}
+
+
+inline int
+vsnprintf_(char *restrict s, size_t size, const char *restrict fmt, va_list ap)
+{
+	int  len;
+
+	len = vsnprintf(s, size, fmt, ap);
+	if (len == -1)
+		return -1;
+	if ((size_t) len >= size)
+		return -1;
+
+	return len;
+}
+
+
+#endif  // include guard