/*
 * CDDL HEADER START
 *
 * The contents of this file are subject to the terms of the
 * Common Development and Distribution License, Version 1.0 only
 * (the "License").  You may not use this file except in compliance
 * with the License.
 *
 * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE
 * or http://www.opensolaris.org/os/licensing.
 * See the License for the specific language governing permissions
 * and limitations under the License.
 *
 * When distributing Covered Code, include this CDDL HEADER in each
 * file and include the License file at usr/src/OPENSOLARIS.LICENSE.
 * If applicable, add the following below this CDDL HEADER, with the
 * fields enclosed by brackets "[]" replaced with your own identifying
 * information: Portions Copyright [yyyy] [name of copyright owner]
 *
 * CDDL HEADER END
 */
/*
 * Copyright (c) 1998-2000 by Sun Microsystems, Inc.
 * All rights reserved.
 */

#include <stdlib.h>
#include <unistd.h>
#include <errno.h>
#include "libproc.h"

typedef union {
        offset_t        full;           /* full 64 bit offset value */
        uint32_t        half[2];        /* two 32-bit halves */
} offsets_t;

/*
 * lseek() system call -- executed by subject process.
 */
off_t
pr_lseek(struct ps_prochandle *Pr, int filedes, off_t offset, int whence)
{
        int syscall;            /* SYS_lseek or SYS_llseek */
        int nargs;              /* 3 or 4, depending on syscall */
        offsets_t off;
        sysret_t rval;          /* return value from lseek() */
        argdes_t argd[4];       /* arg descriptors for lseek() */
        argdes_t *adp;
        int error;

        if (Pr == NULL)
                return (lseek(filedes, offset, whence));

        adp = &argd[0];         /* filedes argument */
        adp->arg_value = filedes;
        adp->arg_object = NULL;
        adp->arg_type = AT_BYVAL;
        adp->arg_inout = AI_INPUT;
        adp->arg_size = 0;

        adp++;                  /* offset argument */
        if (Pstatus(Pr)->pr_dmodel == PR_MODEL_NATIVE) {
                syscall = SYS_lseek;
                nargs = 3;
                adp->arg_value = offset;
                adp->arg_object = NULL;
                adp->arg_type = AT_BYVAL;
                adp->arg_inout = AI_INPUT;
                adp->arg_size = 0;
        } else {
                syscall = SYS_llseek;
                nargs = 4;
                off.full = offset;
                adp->arg_value = off.half[0];   /* first 32 bits */
                adp->arg_object = NULL;
                adp->arg_type = AT_BYVAL;
                adp->arg_inout = AI_INPUT;
                adp->arg_size = 0;
                adp++;
                adp->arg_value = off.half[1];   /* second 32 bits */
                adp->arg_object = NULL;
                adp->arg_type = AT_BYVAL;
                adp->arg_inout = AI_INPUT;
                adp->arg_size = 0;
        }

        adp++;                  /* whence argument */
        adp->arg_value = whence;
        adp->arg_object = NULL;
        adp->arg_type = AT_BYVAL;
        adp->arg_inout = AI_INPUT;
        adp->arg_size = 0;

        error = Psyscall(Pr, &rval, syscall, nargs, &argd[0]);

        if (error) {
                errno = (error > 0)? error : ENOSYS;
                return ((off_t)(-1));
        }

        if (Pstatus(Pr)->pr_dmodel == PR_MODEL_NATIVE)
                offset = rval.sys_rval1;
        else {
                off.half[0] = (uint32_t)rval.sys_rval1;
                off.half[1] = (uint32_t)rval.sys_rval2;
                offset = (off_t)off.full;
        }

        return (offset);
}

/*
 * llseek() system call -- executed by subject process.
 */
offset_t
pr_llseek(struct ps_prochandle *Pr, int filedes, offset_t offset, int whence)
{
        int syscall;            /* SYS_lseek or SYS_llseek */
        int nargs;              /* 3 or 4, depending on syscall */
        offsets_t off;
        sysret_t rval;          /* return value from llseek() */
        argdes_t argd[4];       /* arg descriptors for llseek() */
        argdes_t *adp;
        int error;

        if (Pr == NULL)
                return (llseek(filedes, offset, whence));

        adp = &argd[0];         /* filedes argument */
        adp->arg_value = filedes;
        adp->arg_object = NULL;
        adp->arg_type = AT_BYVAL;
        adp->arg_inout = AI_INPUT;
        adp->arg_size = 0;

        adp++;                  /* offset argument */
        if (Pstatus(Pr)->pr_dmodel == PR_MODEL_LP64) {
                syscall = SYS_lseek;
                nargs = 3;
                adp->arg_value = offset;
                adp->arg_object = NULL;
                adp->arg_type = AT_BYVAL;
                adp->arg_inout = AI_INPUT;
                adp->arg_size = 0;
        } else {
                syscall = SYS_llseek;
                nargs = 4;
                off.full = offset;
                adp->arg_value = off.half[0];   /* first 32 bits */
                adp->arg_object = NULL;
                adp->arg_type = AT_BYVAL;
                adp->arg_inout = AI_INPUT;
                adp->arg_size = 0;
                adp++;
                adp->arg_value = off.half[1];   /* second 32 bits */
                adp->arg_object = NULL;
                adp->arg_type = AT_BYVAL;
                adp->arg_inout = AI_INPUT;
                adp->arg_size = 0;
        }

        adp++;                  /* whence argument */
        adp->arg_value = whence;
        adp->arg_object = NULL;
        adp->arg_type = AT_BYVAL;
        adp->arg_inout = AI_INPUT;
        adp->arg_size = 0;

        error = Psyscall(Pr, &rval, syscall, nargs, &argd[0]);

        if (error) {
                errno = (error > 0)? error : ENOSYS;
                return ((offset_t)(-1));
        }

        if (Pstatus(Pr)->pr_dmodel == PR_MODEL_LP64)
                offset = rval.sys_rval1;
        else {
                off.half[0] = (uint32_t)rval.sys_rval1;
                off.half[1] = (uint32_t)rval.sys_rval2;
                offset = off.full;
        }

        return (offset);
}