nuttx/binfmt/pcode.c
2014-05-08 11:18:55 -06:00

384 lines
11 KiB
C

/****************************************************************************
* binfmt/pcode.c
*
* Copyright (C) 2014 Gregory Nutt. All rights reserved.
* Author: Gregory Nutt <gnutt@nuttx.org>
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
*
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in
* the documentation and/or other materials provided with the
* distribution.
* 3. Neither the name NuttX nor the names of its contributors may be
* used to endorse or promote products derived from this software
* without specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
* "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
* LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS
* FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE
* COPYRIGHT OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT,
* INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING,
* BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS
* OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED
* AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
* LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN
* ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
* POSSIBILITY OF SUCH DAMAGE.
*
****************************************************************************/
/****************************************************************************
* Included Files
****************************************************************************/
#include <nuttx/config.h>
#include <sys/mount.h>
#include <stdint.h>
#include <stdlib.h>
#include <string.h>
#include <fcntl.h>
#include <errno.h>
#include <debug.h>
#include <nuttx/poff.h>
#include <nuttx/fs/ramdisk.h>
#include <nuttx/binfmt/binfmt.h>
#include <nuttx/binfmt/pcode.h>
#ifdef CONFIG_PCODE
/****************************************************************************
* Pre-processor Definitions
****************************************************************************/
/* Check configuration. This is not all of the configuration settings that
* are required -- only the more obvious.
*/
#if CONFIG_NFILE_DESCRIPTORS < 1
# error "You must provide file descriptors via CONFIG_NFILE_DESCRIPTORS in your configuration file"
#endif
#ifdef CONFIG_BINFMT_DISABLE
# error "The binary loader is disabled (CONFIG_BINFMT_DISABLE)!"
#endif
#ifndef CONFIG_PCODE
# error "You must select CONFIG_PCODE in your configuration file"
#endif
#ifdef CONFIG_PCODE_TEST_FS
# ifndef CONFIG_FS_ROMFS
# error "You must select CONFIG_FS_ROMFS in your configuration file"
# endif
# ifdef CONFIG_DISABLE_MOUNTPOINT
# error "You must not disable mountpoints via CONFIG_DISABLE_MOUNTPOINT in your configuration file"
# endif
# ifndef CONFIG_PCODE_TEST_DEVMINOR
# define CONFIG_PCODE_TEST_DEVMINOR 0
# endif
# ifndef CONFIG_PCODE_TEST_DEVPATH
# define CONFIG_PCODE_TEST_DEVPATH "/dev/ram0"
# endif
# ifndef CONFIG_PCODE_TEST_MOUNTPOINT
# define CONFIG_PCODE_TEST_MOUNTPOINT "/bin"
# endif
#endif
/* Describe the ROMFS file system */
#define SECTORSIZE 512
#define NSECTORS(b) (((b)+SECTORSIZE-1)/SECTORSIZE)
/****************************************************************************
* Private Function Prototypes
****************************************************************************/
static int pcode_loadbinary(FAR struct binary_s *binp);
/****************************************************************************
* Private Data
****************************************************************************/
static struct binfmt_s g_pcode_binfmt =
{
NULL, /* next */
pcode_loadbinary, /* load */
};
#ifdef CONFIG_PCODE_TEST_FS
# include "romfs.h"
#endif
/****************************************************************************
* Private Functions
****************************************************************************/
/****************************************************************************
* Name: pcode_mount_testfs
*
* Description:
* If so configured, then mount the P-Code test file system
*
****************************************************************************/
#ifdef CONFIG_PCODE_TEST_FS
static int pcode_mount_testfs(void)
{
int ret;
/* Create a ROM disk for the ROMFS filesystem */
bvdbg("Registering romdisk at /dev/ram%d\n", CONFIG_PCODE_TEST_DEVMINOR);
ret = romdisk_register(CONFIG_PCODE_TEST_DEVMINOR, (FAR uint8_t *)romfs_img,
NSECTORS(ROMFS_IMG_LEN), SECTORSIZE);
if (ret < 0)
{
bdbg("ERROR: romdisk_register failed: %d\n", ret);
return ret;
}
/* Mount the test file system */
bvdbg("Mounting ROMFS filesystem at target=%s with source=%s\n",
CONFIG_PCODE_TEST_MOUNTPOINT, CONFIG_PCODE_TEST_DEVPATH);
ret = mount(CONFIG_PCODE_TEST_DEVPATH, CONFIG_PCODE_TEST_MOUNTPOINT,
"romfs", MS_RDONLY, NULL);
if (ret < 0)
{
int errval = errno;
DEBUGASSERT(errval > 0);
bdbg("ERROR: mount(%s,%s,romfs) failed: %d\n",
CONFIG_PCODE_TEST_DEVPATH, CONFIG_PCODE_TEST_MOUNTPOINT, errval);
return -errval;
}
/* Does the system support the PATH variable? Has the PATH variable
* already been set? If YES and NO, then set the PATH variable to
* the ROMFS mountpoint.
*/
#if defined(CONFIG_BINFMT_EXEPATH) && !defined(CONFIG_PATH_INITIAL)
(void)setenv("PATH", CONFIG_PCODE_TEST_MOUNTPOINT, 1);
#endif
return OK;
}
#else
# define pcode_mount_testfs() (OK)
#endif
/****************************************************************************
* Name: pcode_proxy
*
* Description:
* This is the proxy program that runs and starts the P-Code interpreter.
*
****************************************************************************/
#ifndef CONFIG_NUTTX_KERNEL
static int pcode_proxy(int argc, char **argv)
{
/* REVISIT: There are issues here when CONFIG_NUTTX_KERNEL is selected. */
bdbg("ERROR: Not implemented\n");
return EXIT_FAILURE;
}
#else
# error Missing logic for the case of CONFIG_NUTTX_KERNEL
#endif
/****************************************************************************
* Name: pcode_loadbinary
*
* Description:
* Verify that the file is an pcode binary.
*
****************************************************************************/
static int pcode_loadbinary(struct binary_s *binp)
{
FAR struct poff_fileheader_s hdr;
FAR uint8_t *ptr;
size_t remaining;
ssize_t nread;
int fd;
int ret;
bvdbg("Loading file: %s\n", binp->filename);
/* Open the binary file for reading (only) */
fd = open(binp->filename, O_RDONLY);
if (fd < 0)
{
int errval = errno;
bdbg("ERROR: Failed to open binary %s: %d\n", binp->filename, errval);
return -errval;
}
/* Read the POFF file header */
for (remaining = sizeof(struct poff_fileheader_s), ptr = (FAR uint8_t *)&hdr;
remaining > 0; )
{
/* Read the next GULP */
nread = read(fd, ptr, remaining);
if (nread < 0)
{
/* If errno is EINTR, then this is not an error; the read() was
* simply interrupted by a signal.
*/
int errval = errno;
DEBUGASSERT(errval > 0);
if (errval != EINTR)
{
bdbg("ERROR: read failed: %d\n", errval);
ret = -errval;
goto errout_with_fd;
}
bdbg("Interrupted by a signal\n");
}
else
{
/* Set up for the next gulp */
DEBUGASSERT(nread > 0 && nread <=remaining);
remaining -= nread;
ptr += nread;
}
}
#ifdef CONFIG_PCODE_DUMPBUFFER
lib_dumpbuffer("POFF File Header", &hdr, sizeof(poff_fileheader_s));
#endif
/* Verify that the file is a P-Code executable */
if (memcmp(&hdr.fh_ident, FHI_POFF_MAG, 4) != 0 || hdr.fh_type != FHT_EXEC)
{
dbg("ERROR: File is not a P-code executable: %d\n");
ret = -ENOEXEC;
goto errout_with_fd;
}
/* Return the load information.
* REVISIT: There are issues here when CONFIG_NUTTX_KERNEL is selected.
*/
binp->entrypt = pcode_proxy;
binp->stacksize = CONFIG_PCODE_STACKSIZE;
binp->priority = CONFIG_PCODE_PRIORITY;
/* Successfully identified a p-code binary */
ret = OK;
errout_with_fd:
close(fd);
return ret;
}
/****************************************************************************
* Public Functions
****************************************************************************/
/****************************************************************************
* Name: pcode_initialize
*
* Description:
* P-code support is built based on the configuration. However, in order
* to use this binary format, this function must be called during system
* initialization in order to register the P-Code binary format.
*
* Returned Value:
* This is a NuttX internal function so it follows the convention that
* 0 (OK) is returned on success and a negated errno is returned on
* failure.
*
****************************************************************************/
int pcode_initialize(void)
{
int ret;
/* Mount the test file system */
ret = pcode_mount_testfs();
if (ret < 0)
{
bdbg("ERROR: Failed to mount test file system: %d\n", ret);
return ret;
}
/* Register ourselves as a binfmt loader */
bvdbg("Registering P-Code Loader\n");
ret = register_binfmt(&g_pcode_binfmt);
if (ret != 0)
{
bdbg("Failed to register binfmt: %d\n", ret);
}
return ret;
}
/****************************************************************************
* Name: pcode_uninitialize
*
* Description:
* Unregister the pcode binary loader
*
* Returned Value:
* None
*
****************************************************************************/
void pcode_uninitialize(void)
{
int ret;
/* Unregister the binary format */
ret = unregister_binfmt(&g_pcode_binfmt);
if (ret < 0)
{
int errval = errno;
DEBUGASSERT(errval > 0);
bdbg("ERROR: unregister_binfmt() failed: %d\n", errval);
UNUSED(errval);
}
#ifdef CONFIG_PCODE_TEST_FS
ret = umount(CONFIG_PCODE_TEST_MOUNTPOINT);
if (ret < 0)
{
int errval = errno;
DEBUGASSERT(errval > 0);
bdbg("ERROR: umount(%s) failed: %d\n", CONFIG_PCODE_TEST_MOUNTPOINT, errval);
UNUSED(errval);
}
#endif
}
#endif /* CONFIG_PCODE */