/*
 * CDDL HEADER START
 *
 * The contents of this file are subject to the terms of the
 * Common Development and Distribution License (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 2010 Sun Microsystems, Inc.  All rights reserved.
 * Use is subject to license terms.
 */

        .file   "_rtboot.s"

/ bootstrap routine for run-time linker
/ we get control from exec which has loaded our text and
/ data into the process' address space and created the process
/ stack
/
/ on entry, the process stack looks like this:
/
/                       # <- %esp
/_______________________#  high addresses
/       strings         #
/_______________________#
/       0 word          #
/_______________________#
/       Auxiliary       #
/       entries         #
/       ...             #
/       (size varies)   #
/_______________________#
/       0 word          #
/_______________________#
/       Environment     #
/       pointers        #
/       ...             #
/       (one word each) #
/_______________________#
/       0 word          #
/_______________________#
/       Argument        # low addresses
/       pointers        #
/       Argc words      #
/_______________________#
/       argc            #
/_______________________# <- %ebp

#include <SYS.h>

        .set    EB_NULL,0
        .set    EB_DYNAMIC,1
        .set    EB_LDSO_BASE,2
        .set    EB_ARGV,3
        .set    EB_ENVP,4
        .set    EB_AUXV,5
        .set    EB_DEVZERO,6
        .set    EB_PAGESIZE,7
        .set    EB_MAX,8
        .set    EB_MAX_SIZE32,64

        .text
        .globl  __rtboot
        .globl  __rtld
        .type   __rtboot,@function
        .align  4
__rtboot:
        movl    %esp,%ebp
        subl    $EB_MAX_SIZE32,%esp     / make room for a max sized boot vector
        movl    %esp,%esi               / use esi as a pointer to &eb[0]
        movl    $EB_ARGV,0(%esi)        / set up tag for argv
        leal    4(%ebp),%eax            / get address of argv
        movl    %eax,4(%esi)            / put after tag
        movl    $EB_ENVP,8(%esi)        / set up tag for envp
        movl    (%ebp),%eax             / get # of args
        addl    $2,%eax                 / one for the zero & one for argc
        leal    (%ebp,%eax,4),%edi      / now points past args & @ envp
        movl    %edi,12(%esi)           / set envp
        addl    $-4,%edi                / start loop at &env[-1]
.L00:   addl    $4,%edi                 / next
        cmpl    $0,(%edi)               / search for 0 at end of env
        jne     .L00
        addl    $4,%edi                 / advance past 0
        movl    $EB_AUXV,16(%esi)       / set up tag for auxv
        movl    %edi,20(%esi)           / point to auxv
        movl    $EB_NULL,24(%esi)       / set up NULL tag
        call    .L01            / only way to get IP into a register
.L01:   popl    %ebx            / pop the IP we just "pushed"
        leal    s.EMPTY - .L01(%ebx),%eax
        pushl   %eax
        leal    s.ZERO - .L01(%ebx),%eax
        pushl   %eax
        leal    s.LDSO - .L01(%ebx),%eax
        pushl   %eax
        movl    %esp,%edi       / save pointer to strings
        leal    f.MUNMAP - .L01(%ebx),%eax
        pushl   %eax
        leal    f.CLOSE - .L01(%ebx),%eax
        pushl   %eax
        leal    f.SYSCONFIG - .L01(%ebx),%eax
        pushl   %eax
        leal    f.FSTATAT - .L01(%ebx),%eax
        pushl   %eax
        leal    f.MMAP - .L01(%ebx),%eax
        pushl   %eax
        leal    f.OPENAT - .L01(%ebx),%eax
        pushl   %eax
        leal    f.PANIC - .L01(%ebx),%eax
        pushl   %eax
        movl    %esp,%ecx       / save pointer to functions

        pushl   %ecx            / address of functions
        pushl   %edi            / address of strings
        pushl   %esi            / &eb[0]
        call    __rtld          / __rtld(&eb[0], strings, funcs)
        movl    %esi,%esp       / restore the stack (but leaving boot vector)
        jmp     *%eax           / transfer control to ld.so.1
        .size   __rtboot,.-__rtboot

        .align  4
s.LDSO:         .string "/usr/lib/ld.so.1"
s.ZERO:         .string "/dev/zero"
s.EMPTY:        .string "(null)"
s.ERROR:        .string ": no (or bad) /usr/lib/ld.so.1\n"
l.ERROR:

        .align  4
f.PANIC:
        movl    %esp,%ebp
/ Add using of argument string
        pushl   $l.ERROR - s.ERROR
        call    .L02
.L02:   popl    %ebx
        leal    s.ERROR - .L02(%ebx),%eax
        pushl   %eax
        pushl   $2
        call    f.WRITE
        jmp     f.EXIT
/ Not reached

f.OPENAT:
        movl    $SYS_openat,%eax
        jmp     __syscall
f.MMAP:
        movl    $SYS_mmap,%eax
        jmp     __syscall
f.MUNMAP:
        movl    $SYS_munmap,%eax
        jmp     __syscall
f.READ:
        movl    $SYS_read,%eax
        jmp     __syscall
f.WRITE:
        movl    $SYS_write,%eax
        jmp     __syscall
f.LSEEK:
        movl    $SYS_lseek,%eax
        jmp     __syscall
f.CLOSE:
        movl    $SYS_close,%eax
        jmp     __syscall
f.FSTATAT:
        movl    $SYS_fstatat,%eax
        jmp     __syscall
f.SYSCONFIG:
        movl    $SYS_sysconfig,%eax
        jmp     __syscall
f.EXIT:
        movl    $SYS_exit,%eax
/       jmp     __syscall
__syscall:
        int     $T_SYSCALLINT
        jc      __err_exit
        ret
__err_exit:
        movl    $-1,%eax
        ret