1 files changed, 74 insertions, 0 deletions
diff --git a/qemu/roms/openbios/fs/iso9660/iso9660_read.c b/qemu/roms/openbios/fs/iso9660/iso9660_read.c
new file mode 100644
index 000000000..22cc463f0
--- /dev/null
+++ b/qemu/roms/openbios/fs/iso9660/iso9660_read.c
@@ -0,0 +1,74 @@
+/*
+ *
+ * (c) 2005-2009 Laurent Vivier <Laurent@vivier.eu>
+ *
+ * This file has been copied from EMILE, http://emile.sf.net
+ *
+ */
+
+#include "libiso9660.h"
+#include "libopenbios/bindings.h"
+#include "libc/diskio.h"
+
+size_t iso9660_read(iso9660_FILE *_file, char *buf, size_t count)
+{
+	iso9660_FILE *file = (iso9660_FILE*)_file;
+	size_t read = 0;
+
+	if ( count > (file->size  - file->offset) )
+		count = file->size  - file->offset;
+
+	while (count > 0)
+	{
+		size_t part;
+		int offset_extent;
+		int offset_index;
+
+		offset_extent = file->base +
+				    (file->offset / ISOFS_BLOCK_SIZE);
+		offset_index = file->offset % ISOFS_BLOCK_SIZE;
+
+		if (file->current != offset_extent)
+		{
+			if ( (offset_index == 0) &&
+			     (count >= ISOFS_BLOCK_SIZE) )
+			{
+				/* direct i/o */
+
+				int extents_nb;
+
+				extents_nb = count / ISOFS_BLOCK_SIZE;
+
+				part = extents_nb * ISOFS_BLOCK_SIZE;
+
+				seek_io(file->volume->fd,
+					offset_extent * ISOFS_BLOCK_SIZE);
+				read_io(file->volume->fd, buf + read, part);
+
+				file->offset += part;
+				count -= part;
+				read += part;
+
+				continue;
+			}
+
+			file->current = offset_extent;
+			seek_io(file->volume->fd,
+				offset_extent * ISOFS_BLOCK_SIZE);
+			read_io(file->volume->fd, file->buffer,
+				ISOFS_BLOCK_SIZE);
+		}
+
+		part = ISOFS_BLOCK_SIZE - offset_index;
+		if (count < part)
+			part = count;
+
+		memcpy(buf + read, file->buffer + offset_index, part);
+
+		file->offset += part;
+		count -= part;
+		read += part;
+	}
+
+	return read;
+}