/* 
 * $Locker:  $
 *
 * Copyright (c) 1990, Transarc Corporation.  All rights reserved.
 *
 * export -	EXPORT kernel extension
 */

#define _KERNEL
#include "sys/types.h"
#include "sys/user.h"
#include "sys/conf.h"
#include "sys/errno.h"
#include "sys/device.h"
#include "sys/uio.h"
#include "sys/pri.h"
#include "sys/malloc.h"
#include "sym.h"
#include "export.h"

#undef RELOC

sym_t  *toc_syms;		/* symbol table			*/
int	toc_nsyms;		/* # of symbols			*/
caddr_t toc_strs;		/* string table			*/
int     toc_size;		/* size of toc_syms		*/

/*
 * export	-	entry point to EXPORT kernel extension
 *
 * Input:
 *	cmd	-	add/delete command
 *	uiop	-	uio vector describing any config params
 */
export(cmd, uiop)
struct uio *uiop; {
	int	err, monster;
	static once;

	err     = 0;
	monster = lockl(&kernel_lock, LOCK_SHORT);

	switch (cmd) {
	    case CFG_INIT:			/* add EXPORT		*/
		if (err = config(uiop))
			export_cleanup();
		break;

	    case CFG_TERM:			/* remove EXPORT	*/
		if (err = export_cleanup())
			break;
		break;

	    default:
		err = EINVAL;
		break;
	}

	if (monster != LOCK_NEST)
		unlockl(&kernel_lock);

	return err;
}

/*
 * config -	process configuration data
 */
config(uiop)
register struct uio *uiop; {
	struct k_conf conf;
	register struct export_nl *np;
	register sym_t *sym;
	register err;

	if (err = uiomove((char *)&conf, sizeof (conf), UIO_WRITE, uiop))
		return err;

	toc_nsyms = conf.nsyms;
	toc_size  = conf.symt_sz + conf.str_sz;

	if (toc_nsyms * sizeof (sym_t) != conf.symt_sz
	    || toc_size > (1024 * 1024))
		return EINVAL;

	toc_syms = (sym_t *) xmalloc(toc_size, 2, kernel_heap);

	if (!toc_syms)
		return ENOMEM;

	toc_strs = (char *) &toc_syms[toc_nsyms];

	/*
	 * copy in the symbol table and the string table
	 */
	if (err = copyin(conf.symtab, toc_syms, conf.symt_sz)
	    || (err = copyin(conf.strtab, toc_strs, conf.str_sz))) {
		xmfree(toc_syms, kernel_heap);
		toc_syms = 0;
		return err;
	}

	/*
	 * `TOC' format in kernel has offsets relocated to point directly
	 * into the string table.
	 */
	for (sym = toc_syms; sym < &toc_syms[toc_nsyms]; ++sym)
		if (sym->n_zeroes == 0)
			sym->n_nptr = sym->n_offset + toc_strs;

	return 0;
}

/*
 * export_cleanup -	cleanup EXPORT prior to removing kernel extension
 */
export_cleanup() {

	/*
	 * get rid of the symbol table
	 */
	if (toc_syms) {
		xmfree(toc_syms, kernel_heap);
		toc_syms = 0;
		toc_size = 0;
		toc_strs = 0;
	}

	return 0;
}

/*
 * import_kfunc -	import a kernel function that was mistakenly left
 *			off the exports list
 *
 * NOTE:
 *	We are assuming that the functions we are importing from the
 *	kernel really are within the kernel.  If they are actually
 *	exported from some other kernel extension (but referenced in
 *	the /unix symbol table) we are in trouble.
 */
import_kfunc(struct k_func *kfp) {
	register sym_t *sym;
	register caddr_t *toc;
	register i, pri;
	static u_int *g_toc;

	if (!g_toc) {
		sym = sym_lookup("g_toc", 0);
		if (!sym) {
			printf("\nimport: can't ascertain kernel's TOC\n");
			return EINVAL;
		}
		g_toc = (u_int *) sym->n_value;
	}

	sym = sym_lookup(kfp->name, 0);
	if (!sym) {
		printf("\nimport: function `%s' not found\n", kfp->name);
		return EINVAL;
	}

	kfp->fdesc[0] = sym->n_value;
	kfp->fdesc[1] = *g_toc;
	kfp->fdesc[2] = 0;

	*(u_int **) kfp->fpp = kfp->fdesc;

	return 0;
}

/*
 * import_kvar -	import a kernel variable that was mistakenly left
 *			off the exports list
 */
import_kvar(struct k_var *kvp, caddr_t *toc) {
	register sym_t *sym;
	register i, pri;
	label_t jmpbuf;

	switch (setjmpx(&jmpbuf)) {
	    case 0:
		break;

	    default:
		return EINVAL;
	}

	sym = sym_lookup(kvp->name, 0);
	if (!sym) {
		printf("\nimport: variable `%s' not found\n", kvp->name);
		longjmpx(EINVAL);
	}

	/*
	 * look through the caller's TOC for the reference to his surrogate
	 * variable.
	 */
	while (*toc != kvp->varp)
		++toc;

	printf("import(%s): replacing my TOC at 0x%x: 0x%8x with 0x%8x\n"
	       , kvp->name, toc, *toc, sym->n_value);

	/*
	 * replace reference to surrogate with reference real
	 */
	pri = i_disable(INTMAX);
	*toc = (caddr_t) sym->n_value;
	i_enable(pri);

	clrjmpx(&jmpbuf);

	return 0;
}


/*
 * Call vanilla syscalls
 */
osetgroups(ngroups, gidset)
    int ngroups;
    gid_t *gidset;
{
    int error;

    error = setgroups(ngroups, gidset);
    return (error);
}


okioctl(fdes, cmd, arg, ext)
    int fdes, cmd, arg;
    caddr_t ext;
{
    int error;
    
    error = kioctl(fdes, cmd, arg, ext);
    return (error);
}

#ifdef	notdef
ocore(signo, sigctx)
    char signo;
    struct sigcontext *sigctx;
{
    int error;
#include <sys/user.h>
    u.u_sigflags[signo] |= SA_FULLDUMP;		/* XXX */
    error = core(signo, sigctx);
    return (error);
}
#endif