--- /dev/null
+/*
+ * Copyright (C) 2007 Michael Brown <mbrown@fensystems.co.uk>.
+ *
+ * This program 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 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 Street, Fifth Floor, Boston, MA
+ * 02110-1301, USA.
+ */
+
+FILE_LICENCE ( GPL2_OR_LATER );
+
+#include <string.h>
+#include <stdlib.h>
+#include <stdio.h>
+#include <errno.h>
+#include <ipxe/iobuf.h>
+#include <ipxe/xfer.h>
+#include <ipxe/open.h>
+
+/** @file
+ *
+ * Data transfer interfaces
+ *
+ */
+
+/**
+ * Dummy transfer metadata
+ *
+ * This gets passed to xfer_interface::deliver() and equivalents when
+ * no metadata is available.
+ */
+static struct xfer_metadata dummy_metadata;
+
+/*****************************************************************************
+ *
+ * Data transfer interface operations
+ *
+ */
+
+/**
+ * Send redirection event
+ *
+ * @v intf Data transfer interface
+ * @v type New location type
+ * @v args Remaining arguments depend upon location type
+ * @ret rc Return status code
+ */
+int xfer_vredirect ( struct interface *intf, int type, va_list args ) {
+ struct interface tmp = INTF_INIT ( null_intf_desc );
+ struct interface *dest;
+ xfer_vredirect_TYPE ( void * ) *op =
+ intf_get_dest_op_no_passthru ( intf, xfer_vredirect, &dest );
+ void *object = intf_object ( dest );
+ int rc;
+
+ DBGC ( INTF_COL ( intf ), "INTF " INTF_INTF_FMT " redirect\n",
+ INTF_INTF_DBG ( intf, dest ) );
+
+ if ( op ) {
+ rc = op ( object, type, args );
+ } else {
+ /* Default is to reopen the interface as instructed,
+ * then send xfer_window_changed() messages to both
+ * new child and parent interfaces. Since our
+ * original child interface is likely to be closed and
+ * unplugged as a result of the call to
+ * xfer_vreopen(), we create a temporary interface in
+ * order to be able to send xfer_window_changed() to
+ * the parent.
+ */
+ intf_plug ( &tmp, dest );
+ rc = xfer_vreopen ( dest, type, args );
+ if ( rc == 0 ) {
+ xfer_window_changed ( dest );
+ xfer_window_changed ( &tmp );
+ }
+ intf_unplug ( &tmp );
+ }
+
+ if ( rc != 0 ) {
+ DBGC ( INTF_COL ( intf ), "INTF " INTF_INTF_FMT " redirect "
+ "failed: %s\n", INTF_INTF_DBG ( intf, dest ),
+ strerror ( rc ) );
+ }
+
+ intf_put ( dest );
+ return rc;
+}
+
+/**
+ * Check flow control window
+ *
+ * @v intf Data transfer interface
+ * @ret len Length of window
+ */
+size_t xfer_window ( struct interface *intf ) {
+ struct interface *dest;
+ xfer_window_TYPE ( void * ) *op =
+ intf_get_dest_op ( intf, xfer_window, &dest );
+ void *object = intf_object ( dest );
+ size_t len;
+
+ if ( op ) {
+ len = op ( object );
+ } else {
+ /* Default is to provide an unlimited window */
+ len = ~( ( size_t ) 0 );
+ }
+
+ intf_put ( dest );
+ return len;
+}
+
+/**
+ * Report change of flow control window
+ *
+ * @v intf Data transfer interface
+ *
+ * Note that this method is used to indicate only unsolicited changes
+ * in the flow control window. In particular, this method must not be
+ * called as part of the response to xfer_deliver(), since that could
+ * easily lead to an infinite loop. Callers of xfer_deliver() should
+ * assume that the flow control window will have changed without
+ * generating an xfer_window_changed() message.
+ */
+void xfer_window_changed ( struct interface *intf ) {
+ struct interface *dest;
+ xfer_window_changed_TYPE ( void * ) *op =
+ intf_get_dest_op ( intf, xfer_window_changed, &dest );
+ void *object = intf_object ( dest );
+
+ if ( op ) {
+ op ( object );
+ } else {
+ /* Default is to do nothing */
+ }
+
+ intf_put ( dest );
+}
+
+/**
+ * Allocate I/O buffer
+ *
+ * @v intf Data transfer interface
+ * @v len I/O buffer payload length
+ * @ret iobuf I/O buffer
+ */
+struct io_buffer * xfer_alloc_iob ( struct interface *intf, size_t len ) {
+ struct interface *dest;
+ xfer_alloc_iob_TYPE ( void * ) *op =
+ intf_get_dest_op ( intf, xfer_alloc_iob, &dest );
+ void *object = intf_object ( dest );
+ struct io_buffer *iobuf;
+
+ DBGC ( INTF_COL ( intf ), "INTF " INTF_INTF_FMT " alloc_iob %zd\n",
+ INTF_INTF_DBG ( intf, dest ), len );
+
+ if ( op ) {
+ iobuf = op ( object, len );
+ } else {
+ /* Default is to allocate an I/O buffer with no
+ * reserved space.
+ */
+ iobuf = alloc_iob ( len );
+ }
+
+ if ( ! iobuf ) {
+ DBGC ( INTF_COL ( intf ), "INTF " INTF_INTF_FMT " alloc_iob "
+ "failed\n", INTF_INTF_DBG ( intf, dest ) );
+ }
+
+ intf_put ( dest );
+ return iobuf;
+}
+
+/**
+ * Deliver datagram
+ *
+ * @v intf Data transfer interface
+ * @v iobuf Datagram I/O buffer
+ * @v meta Data transfer metadata
+ * @ret rc Return status code
+ */
+int xfer_deliver ( struct interface *intf,
+ struct io_buffer *iobuf,
+ struct xfer_metadata *meta ) {
+ struct interface *dest;
+ xfer_deliver_TYPE ( void * ) *op =
+ intf_get_dest_op ( intf, xfer_deliver, &dest );
+ void *object = intf_object ( dest );
+ int rc;
+
+ DBGC ( INTF_COL ( intf ), "INTF " INTF_INTF_FMT " deliver %zd\n",
+ INTF_INTF_DBG ( intf, dest ), iob_len ( iobuf ) );
+
+ if ( op ) {
+ rc = op ( object, iobuf, meta );
+ } else {
+ /* Default is to discard the I/O buffer */
+ free_iob ( iobuf );
+ rc = -EPIPE;
+ }
+
+ if ( rc != 0 ) {
+ DBGC ( INTF_COL ( intf ), "INTF " INTF_INTF_FMT
+ " deliver failed: %s\n",
+ INTF_INTF_DBG ( intf, dest ), strerror ( rc ) );
+ }
+
+ intf_put ( dest );
+ return rc;
+}
+
+/*****************************************************************************
+ *
+ * Data transfer interface helper functions
+ *
+ */
+
+/**
+ * Send redirection event
+ *
+ * @v intf Data transfer interface
+ * @v type New location type
+ * @v ... Remaining arguments depend upon location type
+ * @ret rc Return status code
+ */
+int xfer_redirect ( struct interface *intf, int type, ... ) {
+ va_list args;
+ int rc;
+
+ va_start ( args, type );
+ rc = xfer_vredirect ( intf, type, args );
+ va_end ( args );
+ return rc;
+}
+
+/**
+ * Deliver datagram as I/O buffer without metadata
+ *
+ * @v intf Data transfer interface
+ * @v iobuf Datagram I/O buffer
+ * @ret rc Return status code
+ */
+int xfer_deliver_iob ( struct interface *intf, struct io_buffer *iobuf ) {
+ return xfer_deliver ( intf, iobuf, &dummy_metadata );
+}
+
+/**
+ * Deliver datagram as raw data
+ *
+ * @v intf Data transfer interface
+ * @v data Data
+ * @v len Length of data
+ * @v meta Data transfer metadata
+ * @ret rc Return status code
+ */
+int xfer_deliver_raw_meta ( struct interface *intf, const void *data,
+ size_t len, struct xfer_metadata *meta ) {
+ struct io_buffer *iobuf;
+
+ iobuf = xfer_alloc_iob ( intf, len );
+ if ( ! iobuf )
+ return -ENOMEM;
+
+ memcpy ( iob_put ( iobuf, len ), data, len );
+ return xfer_deliver ( intf, iobuf, meta );
+}
+
+/**
+ * Deliver datagram as raw data without metadata
+ *
+ * @v intf Data transfer interface
+ * @v data Data
+ * @v len Length of data
+ * @ret rc Return status code
+ */
+int xfer_deliver_raw ( struct interface *intf, const void *data, size_t len ) {
+ return xfer_deliver_raw_meta ( intf, data, len, &dummy_metadata );
+}
+
+/**
+ * Deliver formatted string
+ *
+ * @v intf Data transfer interface
+ * @v format Format string
+ * @v args Arguments corresponding to the format string
+ * @ret rc Return status code
+ */
+int xfer_vprintf ( struct interface *intf, const char *format,
+ va_list args ) {
+ va_list args_tmp;
+ char *buf;
+ int len;
+ int rc;
+
+ /* Create temporary string */
+ va_copy ( args_tmp, args );
+ len = vasprintf ( &buf, format, args );
+ if ( len < 0 ) {
+ rc = len;
+ goto err_asprintf;
+ }
+ va_end ( args_tmp );
+
+ /* Transmit string */
+ if ( ( rc = xfer_deliver_raw ( intf, buf, len ) ) != 0 )
+ goto err_deliver;
+
+ err_deliver:
+ free ( buf );
+ err_asprintf:
+ return rc;
+}
+
+/**
+ * Deliver formatted string
+ *
+ * @v intf Data transfer interface
+ * @v format Format string
+ * @v ... Arguments corresponding to the format string
+ * @ret rc Return status code
+ */
+int xfer_printf ( struct interface *intf, const char *format, ... ) {
+ va_list args;
+ int rc;
+
+ va_start ( args, format );
+ rc = xfer_vprintf ( intf, format, args );
+ va_end ( args );
+ return rc;
+}
+
+/**
+ * Seek to position
+ *
+ * @v intf Data transfer interface
+ * @v offset Offset to new position
+ * @ret rc Return status code
+ */
+int xfer_seek ( struct interface *intf, off_t offset ) {
+ struct io_buffer *iobuf;
+ struct xfer_metadata meta = {
+ .flags = XFER_FL_ABS_OFFSET,
+ .offset = offset,
+ };
+
+ DBGC ( INTF_COL ( intf ), "INTF " INTF_FMT " seek to %ld\n",
+ INTF_DBG ( intf ), offset );
+
+ /* Allocate and send a zero-length data buffer */
+ iobuf = xfer_alloc_iob ( intf, 0 );
+ if ( ! iobuf )
+ return -ENOMEM;
+
+ return xfer_deliver ( intf, iobuf, &meta );
+}
Code Review / kvmfornfv.git / blobdiff