1 files changed, 75 insertions, 0 deletions
diff --git a/libc/stdio/vasprintf.c b/libc/stdio/vasprintf.c
new file mode 100644
index 000000000..21ef8e145
--- /dev/null
+++ b/libc/stdio/vasprintf.c
@@ -0,0 +1,75 @@
+/* Copyright (C) 2004       Manuel Novoa III    <mjn3@codepoet.org>
+ *
+ * GNU Library General Public License (LGPL) version 2 or later.
+ *
+ * Dedicated to Toni.  See uClibc/DEDICATION.mjn3 for details.
+ */
+
+#include "_stdio.h"
+#include <stdarg.h>
+
+#ifdef __UCLIBC_MJN3_ONLY__
+/* Do the memstream stuff inline to avoid fclose and the openlist? */
+#warning CONSIDER: avoid open_memstream call?
+#endif
+
+#ifndef __STDIO_HAS_VSNPRINTF
+#warning Skipping vasprintf since no vsnprintf!
+#else
+
+int vasprintf(char **__restrict buf, const char * __restrict format,
+			 va_list arg)
+{
+#ifdef __UCLIBC_HAS_GLIBC_CUSTOM_STREAMS__
+
+	FILE *f;
+	size_t size;
+	int rv = -1;
+
+	*buf = NULL;
+
+	if ((f = open_memstream(buf, &size)) != NULL) {
+		rv = vfprintf(f, format, arg);
+		fclose(f);
+		if (rv < 0) {
+			free(*buf);
+			*buf = NULL;
+		}
+	}
+
+	assert(rv >= -1);
+
+	return rv;
+
+#else  /* __UCLIBC_HAS_GLIBC_CUSTOM_STREAMS__ */
+
+	/* This implementation actually calls the printf machinery twice, but only
+	 * only does one malloc.  This can be a problem though when custom printf
+	 * specs or the %m specifier are involved because the results of the
+	 * second call might be different from the first. */
+	va_list arg2;
+	int rv;
+
+	va_copy(arg2, arg);
+ 	rv = vsnprintf(NULL, 0, format, arg2);
+	va_end(arg2);
+
+	*buf = NULL;
+
+	if (rv >= 0) {
+		if ((*buf = malloc(++rv)) != NULL) {
+			if ((rv = vsnprintf(*buf, rv, format, arg)) < 0) {
+				free(*buf);
+				*buf = NULL;
+			}
+		}
+	}
+
+	assert(rv >= -1);
+
+	return rv;
+
+#endif /* __UCLIBC_HAS_GLIBC_CUSTOM_STREAMS__ */
+}
+
+#endif