Commit yaboot 1.3.0

[yaboot.git] / include / ext2fs / ext2_io.h

diff --git a/include/ext2fs/ext2_io.h b/include/ext2fs/ext2_io.h
new file mode 100644 (file)
index 0000000..9568866
--- /dev/null
+++ b/include/ext2fs/ext2_io.h
@@ -0,0 +1,94 @@
+/*
+ * io.h --- the I/O manager abstraction
+ * 
+ * Copyright (C) 1993, 1994, 1995, 1996 Theodore Ts'o.
+ *
+ * %Begin-Header%
+ * This file may be redistributed under the terms of the GNU Public
+ * License.
+ * %End-Header%
+ */
+
+#ifndef _EXT2FS_EXT2_IO_H
+#define _EXT2FS_EXT2_IO_H
+
+/*
+ * ext2_loff_t is defined here since unix_io.c needs it.
+ */
+#if defined(__GNUC__) || defined(HAS_LONG_LONG)
+typedef long long      ext2_loff_t;
+#else
+typedef long           ext2_loff_t;
+#endif
+
+/* llseek.c */
+ext2_loff_t ext2fs_llseek (int, ext2_loff_t, int);
+
+typedef struct struct_io_manager *io_manager;
+typedef struct struct_io_channel *io_channel;
+
+struct struct_io_channel {
+       errcode_t       magic;
+       io_manager      manager;
+       char            *name;
+       int             block_size;
+       errcode_t       (*read_error)(io_channel channel,
+                                     unsigned long block,
+                                     int count,
+                                     void *data,
+                                     size_t size,
+                                     int actual_bytes_read,
+                                     errcode_t error);
+       errcode_t       (*write_error)(io_channel channel,
+                                      unsigned long block,
+                                      int count,
+                                      const void *data,
+                                      size_t size,
+                                      int actual_bytes_written,
+                                      errcode_t error);
+       int             refcount;
+       int             reserved[15];
+       void            *private_data;
+       void            *app_data;
+};
+
+struct struct_io_manager {
+       errcode_t magic;
+       const char *name;
+       errcode_t (*open)(const char *name, int flags, io_channel *channel);
+       errcode_t (*close)(io_channel channel);
+       errcode_t (*set_blksize)(io_channel channel, int blksize);
+       errcode_t (*read_blk)(io_channel channel, unsigned long block,
+                             int count, void *data);
+       errcode_t (*write_blk)(io_channel channel, unsigned long block,
+                              int count, const void *data);
+       errcode_t (*flush)(io_channel channel);
+       int             reserved[16];
+};
+
+#define IO_FLAG_RW     1
+
+/*
+ * Convenience functions....
+ */
+#define io_channel_close(c)            ((c)->manager->close((c)))
+#define io_channel_set_blksize(c,s)    ((c)->manager->set_blksize((c),s))
+#define io_channel_read_blk(c,b,n,d)   ((c)->manager->read_blk((c),b,n,d))
+#define io_channel_write_blk(c,b,n,d)  ((c)->manager->write_blk((c),b,n,d))
+#define io_channel_flush(c)            ((c)->manager->flush((c)))
+#define io_channel_bumpcount(c)                ((c)->refcount++)
+       
+/* unix_io.c */
+extern io_manager unix_io_manager;
+
+/* test_io.c */
+extern io_manager test_io_manager, test_io_backing_manager;
+extern void (*test_io_cb_read_blk)
+       (unsigned long block, int count, errcode_t err);
+extern void (*test_io_cb_write_blk)
+       (unsigned long block, int count, errcode_t err);
+extern void (*test_io_cb_set_blksize)
+       (int blksize, errcode_t err);
+
+#endif /* _EXT2FS_EXT2_IO_H */
+