1 files changed, 107 insertions, 0 deletions
diff --git a/lib/sbuf.c b/lib/sbuf.c
new file mode 100644
index 0000000..c04af15
--- /dev/null
+++ b/lib/sbuf.c
@@ -0,0 +1,107 @@
+/*
+ * Simple string buffer
+ *
+ * Copyright (C) 2017 Christian Franke
+ *
+ * This file is part of FRR.
+ *
+ * FRR is free software; you can redistribute it and/or modify it
+ * under the terms of the GNU General Public License as published by the
+ * Free Software Foundation; either version 2, or (at your option) any
+ * later version.
+ *
+ * FRR is distributed in the hope that it will be useful, but
+ * WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+ * General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with FRR; see the file COPYING.  If not, write to the Free
+ * Software Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA
+ * 02111-1307, USA.
+ */
+#include <zebra.h>
+
+#include "printfrr.h"
+#include "sbuf.h"
+#include "memory.h"
+
+void sbuf_init(struct sbuf *dest, char *buf, size_t size)
+{
+	dest->fixed = (size > 0);
+	if (dest->fixed) {
+		dest->buf = buf;
+		dest->size = size;
+	} else {
+		dest->buf = XMALLOC(MTYPE_TMP, 4096);
+		dest->size = 4096;
+	}
+
+	dest->pos = 0;
+	dest->buf[0] = '\0';
+}
+
+void sbuf_reset(struct sbuf *dest)
+{
+	dest->pos = 0;
+	dest->buf[0] = '\0';
+}
+
+const char *sbuf_buf(struct sbuf *buf)
+{
+	return buf->buf;
+}
+
+void sbuf_free(struct sbuf *buf)
+{
+	if (!buf->fixed)
+		XFREE(MTYPE_TMP, buf->buf);
+}
+
+void sbuf_push(struct sbuf *buf, int indent, const char *format, ...)
+{
+	va_list args;
+	int written;
+
+	if (!buf->fixed) {
+		int written1, written2;
+		size_t new_size;
+
+		written1 = indent;
+		va_start(args, format);
+		written2 = vsnprintfrr(NULL, 0, format, args);
+		va_end(args);
+
+		new_size = buf->size;
+		if (written1 >= 0 && written2 >= 0) {
+			while (buf->pos + written1 + written2 >= new_size)
+				new_size *= 2;
+			if (new_size > buf->size) {
+				buf->buf =
+					XREALLOC(MTYPE_TMP, buf->buf, new_size);
+				buf->size = new_size;
+			}
+		}
+	}
+
+	written = snprintf(buf->buf + buf->pos, buf->size - buf->pos, "%*s",
+			   indent, "");
+
+	if (written >= 0)
+		buf->pos += written;
+	if (buf->pos > buf->size)
+		buf->pos = buf->size;
+
+	va_start(args, format);
+	written = vsnprintfrr(buf->buf + buf->pos, buf->size - buf->pos,
+			      format, args);
+	va_end(args);
+
+	if (written >= 0)
+		buf->pos += written;
+	if (buf->pos > buf->size)
+		buf->pos = buf->size;
+
+	if (buf->pos == buf->size)
+		assert(!"Buffer filled up!");
+}