buffer: add buffer_init

Signed-off-by: NGerd Hoffmann <kraxel@redhat.com>
Reviewed-by: NPeter Lieven <pl@kamp.de>
Reviewed-by: NDaniel P. Berrange <berrange@redhat.com>
Message-id: 1446203414-4013-3-git-send-email-kraxel@redhat.com

include/qemu/buffer.h

@@ -34,11 +34,23 @@ typedef struct Buffer Buffer;
  */
 
 struct Buffer {
+    char *name;
     size_t capacity;
     size_t offset;
     uint8_t *buffer;
 };
 
+/**
+ * buffer_init:
+ * @buffer: the buffer object
+ * @name: buffer name
+ *
+ * Optionally attach a name to the buffer, to make it easier
+ * to identify in debug traces.
+ */
+void buffer_init(Buffer *buffer, const char *name, ...)
+        GCC_FMT_ATTR(2, 3);
+
 /**
  * buffer_reserve:
  * @buffer: the buffer object

util/buffer.c

@@ -22,6 +22,15 @@
 
 #define BUFFER_MIN_INIT_SIZE 4096
 
+void buffer_init(Buffer *buffer, const char *name, ...)
+{
+    va_list ap;
+
+    va_start(ap, name);
+    buffer->name = g_strdup_vprintf(name, ap);
+    va_end(ap);
+}
+
 void buffer_reserve(Buffer *buffer, size_t len)
 {
     if ((buffer->capacity - buffer->offset) < len) {
@@ -49,9 +58,11 @@ void buffer_reset(Buffer *buffer)
 void buffer_free(Buffer *buffer)
 {
     g_free(buffer->buffer);
+    g_free(buffer->name);
     buffer->offset = 0;
     buffer->capacity = 0;
     buffer->buffer = NULL;
+    buffer->name = NULL;
 }
 
 void buffer_append(Buffer *buffer, const void *data, size_t len)