/****************************************************************************
* 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 <apps/prun.h>
#include <nuttx/kmalloc.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
#ifndef CONFIG_SCHED_ONEXIT
# error CONFIG_SCHED_ONEXIT is required
#endif
#ifndef CONFIG_PCODE_VARSTACKSIZE
# define CONFIG_PCODE_VARSTACKSIZE 1024
#endif
#ifndef CONFIG_PCODE_STRSTACKSIZE
# define CONFIG_PCODE_STRSTACKSIZE 128
#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
****************************************************************************/
struct binfmt_handoff_s
{
sem_t exclsem; /* Supports mutually exclusive access */
FAR struct binary_s *binp; /* Binary format being handed off */
FAR char *fullpath; /* Full path to the P-Code file */
};
/****************************************************************************
* Private Function Prototypes
****************************************************************************/
static int pcode_load(FAR struct binary_s *binp);
static int pcode_unload(FAR struct binary_s *binp);
/****************************************************************************
* Private Data
****************************************************************************/
static struct binfmt_s g_pcode_binfmt =
{
NULL, /* next */
pcode_load, /* load */
pcode_unload, /* unload */
};
struct binfmt_handoff_s g_pcode_handoff;
#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 = get_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_onexit
*
* Description:
* This is the proxy program that runs and starts the P-Code interpreter.
*
****************************************************************************/
#if !defined(CONFIG_BUILD_PROTECTED) && !defined(CONFIG_BUILD_KERNEL)
static void pcode_onexit(int exitcode, FAR void *arg)
{
FAR struct binary_s *binp = (FAR struct binary_s *)arg;
DEBUGASSERT(binp);
/* And unload the module */
unload_module(binp);
}
#endif
/****************************************************************************
* Name: pcode_proxy
*
* Description:
* This is the proxy program that runs and starts the P-Code interpreter.
*
* REVISIT: There are issues here when CONFIG_BUILD_PROTECTED or
* CONFIG_BUILD_KERNEL are selected. Also this implementation is too highly
* couple to logic in the apps/ directory.
*
****************************************************************************/
#if !defined(CONFIG_BUILD_PROTECTED) && !defined(CONFIG_BUILD_KERNEL)
static int pcode_proxy(int argc, char **argv)
{
FAR struct binary_s *binp;
FAR char *fullpath;
int ret;
/* Get the struct binary_s instance from the handoff structure */
binp = g_pcode_handoff.binp;
g_pcode_handoff.binp = NULL;
fullpath = g_pcode_handoff.fullpath;
g_pcode_handoff.fullpath = NULL;
sem_post(&g_pcode_handoff.exclsem);
DEBUGASSERT(binp && fullpath);
bvdbg("Executing %s\n", fullpath);
/* Set-up the on-exit handler that will unload the module on exit */
ret = on_exit(pcode_onexit, binp);
if (ret < 0)
{
bdbg("ERROR: on_exit failed: %d\n", get_errno());
kmm_free(fullpath);
return EXIT_FAILURE;
}
/* Load the P-code file and execute it */
ret = prun(fullpath, CONFIG_PCODE_VARSTACKSIZE, CONFIG_PCODE_STRSTACKSIZE);
/* We no longer need the fullpath */
kmm_free(fullpath);
/* Check the result of the interpretation */
if (ret < 0)
{
bdbg("ERROR: Execution failed\n");
return EXIT_FAILURE;
}
return EXIT_SUCCESS;
}
#else
# error Missing logic for the case of CONFIG_BUILD_PROTECTED/KERNEL
#endif
/****************************************************************************
* Name: pcode_load
*
* Description:
* Verify that the file is a pcode binary.
*
****************************************************************************/
static int pcode_load(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 = get_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 = get_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_BUILD_PROTECTED or
* CONFIG_BUILD_KERNEL are selected.
*/
binp->entrypt = pcode_proxy;
binp->stacksize = CONFIG_PCODE_STACKSIZE;
binp->priority = CONFIG_PCODE_PRIORITY;
/* Get exclusive access to the p-code handoff structure */
do
{
ret = sem_wait(&g_pcode_handoff.exclsem);
DEBUGASSERT(ret == OK || get_errno() == EINTR);
}
while (ret < 0);
/* Save the data that we need to handoff to the child thread */
DEBUGASSERT(g_pcode_handoff.binp == NULL &&
g_pcode_handoff.fullpath == NULL);
/* Duplicate the full path to the binary */
g_pcode_handoff.fullpath = strdup(binp->filename);
if (!g_pcode_handoff.fullpath)
{
bdbg("ERROR: Failed to duplicate the full path: %d\n",
binp->filename);
sem_post(&g_pcode_handoff.exclsem);
ret = -ENOMEM;
goto errout_with_fd;
}
g_pcode_handoff.binp = binp;
/* Successfully identified (but not really loaded) a p-code binary */
ret = OK;
errout_with_fd:
close(fd);
return ret;
}
/****************************************************************************
* Name: pcode_unload
*
* Description:
* Called when the pcode binary is unloaded. This is necessary primarily
* to handler error conditions where unload_module is called after
* pcode_load without having executed the P-Code module.
*
****************************************************************************/
static int pcode_unload(struct binary_s *binp)
{
/* Increment the semaphore count back to one if appropriate */
if (g_pcode_handoff.binp)
{
g_pcode_handoff.binp = NULL;
sem_post(&g_pcode_handoff.exclsem);
}
return OK;
}
/****************************************************************************
* 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;
/* Initialize globals */
sem_init(&g_pcode_handoff.exclsem, 0, 1);
/* 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 = get_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 = get_errno();
DEBUGASSERT(errval > 0);
bdbg("ERROR: umount(%s) failed: %d\n", CONFIG_PCODE_TEST_MOUNTPOINT, errval);
UNUSED(errval);
}
#endif
/* Uninitialize globals */
sem_destroy(&g_pcode_handoff.exclsem);
}
#endif /* CONFIG_PCODE */
