Add new module kfile_mem: kfile access over a plain memory buffer.

[bertos.git] / bertos / struct / kfile_mem.c

diff --git a/bertos/struct/kfile_mem.c b/bertos/struct/kfile_mem.c
new file mode 100644 (file)
index 0000000..5560fdc
--- /dev/null
+++ b/bertos/struct/kfile_mem.c
@@ -0,0 +1,83 @@
+/**
+ * \file
+ * <!--
+ * This file is part of BeRTOS.
+ *
+ * Bertos 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 of the License, or
+ * (at your option) any later version.
+ *
+ * This program 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 this program; if not, write to the Free Software
+ * Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA  02110-1301  USA
+ *
+ * As a special exception, you may use this file as part of a free software
+ * library without restriction.  Specifically, if other files instantiate
+ * templates or use macros or inline functions from this file, or you compile
+ * this file and link it with other files to produce an executable, this
+ * file does not by itself cause the resulting executable to be covered by
+ * the GNU General Public License.  This exception does not however
+ * invalidate any other reasons why the executable file might be covered by
+ * the GNU General Public License.
+ *
+ * Copyright 2009 Develer S.r.l. (http://www.develer.com/)
+ *
+ * -->
+ *
+ * \brief KFile interface over a memory buffer.
+ *
+ * \version $Id: cfg_adc.h 2348 2009-02-16 13:43:44Z duplo $
+ * \author Francesco Sacchi <batt@develer.com>
+ */
+
+#include "kfile_mem.h"
+
+#include <kern/kfile.h>
+
+#include <string.h>
+
+static size_t kfilemem_read(struct KFile *_fd, void *buf, size_t size)
+{
+       KFileMem *fd = KFILEMEM_CAST(_fd);
+
+       size = MIN((kfile_off_t)size, fd->fd.size - fd->fd.seek_pos);
+       uint8_t *mem = (uint8_t *)fd->mem;
+       memcpy(buf, mem + fd->fd.seek_pos, size);
+       fd->fd.seek_pos += size;
+
+       return size;
+}
+
+static size_t kfilemem_write(struct KFile *_fd, const void *buf, size_t size)
+{
+       KFileMem *fd = KFILEMEM_CAST(_fd);
+
+       size = MIN((kfile_off_t)size, fd->fd.size - fd->fd.seek_pos);
+       uint8_t *mem = (uint8_t *)fd->mem;
+       memcpy(mem + fd->fd.seek_pos, buf, size);
+       fd->fd.seek_pos += size;
+
+       return size;
+}
+
+void kfilemem_init(KFileMem *km, void *mem, size_t len)
+{
+       ASSERT(km);
+       ASSERT(mem);
+       ASSERT(len);
+
+       memset(km, 0, sizeof(*km));
+
+       km->mem = mem;
+       kfile_init(&km->fd);
+       km->fd.read = kfilemem_read;
+       km->fd.write = kfilemem_write;
+       km->fd.size = len;
+       DB(km->fd._type = KFT_KFILEMEM);
+}