/*
* Copyright (C) 2006 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., 675 Mass Ave, Cambridge, MA 02139, USA.
*/
FILE_LICENCE ( GPL2_OR_LATER );
#include <stddef.h>
#include <string.h>
#include <stdlib.h>
#include <stdio.h>
#include <errno.h>
#include <assert.h>
#include <libgen.h>
#include <gpxe/list.h>
#include <gpxe/umalloc.h>
#include <gpxe/uri.h>
#include <gpxe/image.h>
/** @file
*
* Executable/loadable images
*
*/
/** List of registered images */
struct list_head images = LIST_HEAD_INIT ( images );
/**
* Free executable/loadable image
*
* @v refcnt Reference counter
*/
static void free_image ( struct refcnt *refcnt ) {
struct image *image = container_of ( refcnt, struct image, refcnt );
uri_put ( image->uri );
ufree ( image->data );
image_put ( image->replacement );
free ( image );
DBGC ( image, "IMAGE %p freed\n", image );
}
/**
* Allocate executable/loadable image
*
* @ret image Executable/loadable image
*/
struct image * alloc_image ( void ) {
struct image *image;
image = zalloc ( sizeof ( *image ) );
if ( image ) {
image->refcnt.free = free_image;
}
return image;
}
/**
* Set image URI
*
* @v image Image
* @v URI New image URI
* @ret rc Return status code
*
* If no name is set, the name will be updated to the base name of the
* URI path (if any).
*/
int image_set_uri ( struct image *image, struct uri *uri ) {
const char *path = uri->path;
/* Replace URI reference */
uri_put ( image->uri );
image->uri = uri_get ( uri );
/* Set name if none already specified */
if ( path && ( ! image->name[0] ) )
image_set_name ( image, basename ( ( char * ) path ) );
return 0;
}
/**
* Set image command line
*
* @v image Image
* @v cmdline New image command line
* @ret rc Return status code
*/
int image_set_cmdline ( struct image *image, const char *cmdline ) {
free ( image->cmdline );
image->cmdline = strdup ( cmdline );
if ( ! image->cmdline )
return -ENOMEM;
return 0;
}
/**
* Register executable/loadable image
*
* @v image Executable/loadable image
* @ret rc Return status code
*/
int register_image ( struct image *image ) {
static unsigned int imgindex = 0;
/* Create image name if it doesn't already have one */
if ( ! image->name[0] ) {
snprintf ( image->name, sizeof ( image->name ), "img%d",
imgindex++ );
}
/* Add to image list */
image_get ( image );
list_add_tail ( &image->list, &images );
DBGC ( image, "IMAGE %p at [%lx,%lx) registered as %s\n",
image, user_to_phys ( image->data, 0 ),
user_to_phys ( image->data, image->len ), image->name );
return 0;
}
/**
* Unregister executable/loadable image
*
* @v image Executable/loadable image
*/
void unregister_image ( struct image *image ) {
DBGC ( image, "IMAGE %p unregistered\n", image );
list_del ( &image->list );
image_put ( image );
}
/**
* Find image by name
*
* @v name Image name
* @ret image Executable/loadable image, or NULL
*/
struct image * find_image ( const char *name ) {
struct image *image;
list_for_each_entry ( image, &images, list ) {
if ( strcmp ( image->name, name ) == 0 )
return image;
}
return NULL;
}
/**
* Load executable/loadable image into memory
*
* @v image Executable/loadable image
* @v type Executable/loadable image type
* @ret rc Return status code
*/
static int image_load_type ( struct image *image, struct image_type *type ) {
int rc;
/* Check image is actually loadable */
if ( ! type->load )
return -ENOEXEC;
/* Try the image loader */
if ( ( rc = type->load ( image ) ) != 0 ) {
DBGC ( image, "IMAGE %p could not load as %s: %s\n",
image, type->name, strerror ( rc ) );
return rc;
}
/* Flag as loaded */
image->flags |= IMAGE_LOADED;
return 0;
}
/**
* Load executable/loadable image into memory
*
* @v image Executable/loadable image
* @ret rc Return status code
*/
int image_load ( struct image *image ) {
assert ( image->type != NULL );
return image_load_type ( image, image->type );
}
/**
* Autodetect image type and load executable/loadable image into memory
*
* @v image Executable/loadable image
* @ret rc Return status code
*/
int image_autoload ( struct image *image ) {
struct image_type *type;
int rc;
/* If image already has a type, use it */
if ( image->type )
return image_load ( image );
/* Otherwise probe for a suitable type */
for_each_table_entry ( type, IMAGE_TYPES ) {
DBGC ( image, "IMAGE %p trying type %s\n", image, type->name );
rc = image_load_type ( image, type );
if ( image->type == NULL )
continue;
return rc;
}
DBGC ( image, "IMAGE %p format not recognised\n", image );
return -ENOEXEC;
}
/**
* Execute loaded image
*
* @v image Loaded image
* @ret rc Return status code
*/
int image_exec ( struct image *image ) {
struct image *replacement;
struct uri *old_cwuri;
int rc;
/* Image must be loaded first */
if ( ! ( image->flags & IMAGE_LOADED ) ) {
DBGC ( image, "IMAGE %p could not execute: not loaded\n",
image );
return -ENOTTY;
}
assert ( image->type != NULL );
/* Check that image is actually executable */
if ( ! image->type->exec )
return -ENOEXEC;
/* Switch current working directory to be that of the image itself */
old_cwuri = uri_get ( cwuri );
churi ( image->uri );
/* Take out a temporary reference to the image. This allows
* the image to unregister itself if necessary, without
* automatically freeing itself.
*/
image_get ( image );
/* Try executing the image */
if ( ( rc = image->type->exec ( image ) ) != 0 ) {
DBGC ( image, "IMAGE %p could not execute: %s\n",
image, strerror ( rc ) );
/* Do not return yet; we still have clean-up to do */
}
/* Pick up replacement image before we drop the original
* image's temporary reference.
*/
replacement = image->replacement;
/* Drop temporary reference to the original image */
image_put ( image );
/* Reset current working directory */
churi ( old_cwuri );
uri_put ( old_cwuri );
/* Tail-recurse into replacement image, if one exists */
if ( replacement ) {
DBGC ( image, "IMAGE %p replacing self with IMAGE %p\n",
image, replacement );
if ( ( rc = image_exec ( replacement ) ) != 0 )
return rc;
}
return rc;
}
/**
* Register and autoload an image
*
* @v image Image
* @ret rc Return status code
*/
int register_and_autoload_image ( struct image *image ) {
int rc;
if ( ( rc = register_image ( image ) ) != 0 )
return rc;
if ( ( rc = image_autoload ( image ) ) != 0 )
return rc;
return 0;
}
/**
* Register and autoexec an image
*
* @v image Image
* @ret rc Return status code
*/
int register_and_autoexec_image ( struct image *image ) {
int rc;
if ( ( rc = register_and_autoload_image ( image ) ) != 0 )
return rc;
if ( ( rc = image_exec ( image ) ) != 0 )
return rc;
return 0;
}
