Added [v]asprintf()

1 files changed, 47 insertions, 0 deletions

diff --git a/src/core/asprintf.c b/src/core/asprintf.c
new file mode 100644
index 00000000..94d7e7c4
--- /dev/null
+++ b/src/core/asprintf.c
@@ -0,0 +1,47 @@
+#include <stdint.h>
+#include <stddef.h>
+#include <stdlib.h>
+#include <stdio.h>
+#include <errno.h>
+
+/**
+ * Write a formatted string to newly allocated memory.
+ *
+ * @v strp		Pointer to hold allocated string
+ * @v fmt		Format string
+ * @v args		Arguments corresponding to the format string
+ * @ret	len		Length of formatted string
+ */
+int vasprintf ( char **strp, const char *fmt, va_list args ) {
+	size_t len;
+	va_list args_tmp;
+
+	/* Calculate length needed for string */
+	va_copy ( args_tmp, args );
+	len = ( vsnprintf ( NULL, 0, fmt, args_tmp ) + 1 );
+	va_end ( args_tmp );
+
+	/* Allocate and fill string */
+	*strp = malloc ( len );
+	if ( ! *strp )
+		return -ENOMEM;
+	return vsnprintf ( *strp, len, fmt, args );
+}
+
+/**
+ * Write a formatted string to newly allocated memory.
+ *
+ * @v strp		Pointer to hold allocated string
+ * @v fmt		Format string
+ * @v ...		Arguments corresponding to the format string
+ * @ret	len		Length of formatted string
+ */
+int asprintf ( char **strp, const char *fmt, ... ) {
+	va_list args;
+	int len;
+
+	va_start ( args, fmt );
+	len = vasprintf ( strp, fmt, args );
+	va_end ( args );
+	return len;
+}