1 files changed, 57 insertions, 0 deletions
diff --git a/contrib/ccan/asprintf/asprintf.c b/contrib/ccan/asprintf/asprintf.c
new file mode 100644
index 0000000..4077599
--- /dev/null
+++ b/contrib/ccan/asprintf/asprintf.c
@@ -0,0 +1,57 @@
+/* SPDX-License-Identifier: MIT
+ * Source: https://ccodearchive.net/info/asprintf.html */
+#include <ccan/asprintf/asprintf.h>
+#include <stdarg.h>
+#include <stdio.h>
+
+char *PRINTF_FMT(1, 2) afmt(const char *fmt, ...)
+{
+	va_list ap;
+	char *ptr;
+
+	va_start(ap, fmt);
+	/* The BSD version apparently sets ptr to NULL on fail.  GNU loses. */
+	if (vasprintf(&ptr, fmt, ap) < 0)
+		ptr = NULL;
+	va_end(ap);
+	return ptr;
+}
+
+#if !HAVE_ASPRINTF
+#include <stdarg.h>
+#include <stdlib.h>
+
+int vasprintf(char **strp, const char *fmt, va_list ap)
+{
+	int len;
+	va_list ap_copy;
+
+	/* We need to make a copy of ap, since it's a use-once. */
+	va_copy(ap_copy, ap);
+	len = vsnprintf(NULL, 0, fmt, ap_copy);
+	va_end(ap_copy);
+
+	/* Until version 2.0.6 glibc would return -1 on truncated output.
+	 * OTOH, they had asprintf. */
+	if (len < 0)
+		return -1;
+
+	*strp = malloc(len+1);
+	if (!*strp)
+		return -1;
+
+	return vsprintf(*strp, fmt, ap);
+}
+
+int asprintf(char **strp, const char *fmt, ...)
+{
+	va_list ap;
+	int len;
+
+	va_start(ap, fmt);
+	len = vasprintf(strp, fmt, ap);
+	va_end(ap);
+
+	return len;
+}
+#endif /* !HAVE_ASPRINTF */