/*
 * Copyright 2016 The OpenSSL Project Authors. All Rights Reserved.
 *
 * Licensed under the OpenSSL license (the "License").  You may not use
 * this file except in compliance with the License.  You can obtain a copy
 * in the file LICENSE in the source distribution or at
 * https://www.openssl.org/source/license.html
 */

/*
 * This program allows for easy execution of programs in the OpenSSL build
 * directory, in a manner that's similar to how util/shlib_wrap.sh.  Simply
 * take the command you want to execute and prefix that with
 * 'mcr [.util]shlib_wrap', for example:
 *
 * $ mcr [.util]shlib_wrap mcr [.apps]openssl s_client -connect www.openssl.org:443
 */

#ifndef __VMS
# error "VMS ONLY!"
#endif

#include <stdio.h>
#include <descrip.h>
#include <ssdef.h>
#include <lib$routines.h>
{-
    use File::Spec::Functions qw(rel2abs);
    our $sv = sprintf "%02d%02d", $config{shlib_major}, $config{shlib_minor};
    our $pz = $config{pointer_size};
    our $bldd = rel2abs($config{builddir});
    ""
-}
/* The logical name table we check and affect */
$DESCRIPTOR(lnm_process_table, "LNM$PROCESS_TABLE");

/* The first logical name we deal with, the buffer for its old value,
 * and its temporary new value
 */
const $DESCRIPTOR(lnm1, "OSSL$LIBCRYPTO{- $sv -}_SHR{- $pz -}");
char lnm1oldbuf[256]; short lnm1oldlen = 0;
$DESCRIPTOR(lnm1old, lnm1oldbuf);
const $DESCRIPTOR(lnm1new, "{- $bldd -}OSSL$LIBCRYPTO{- $sv -}_SHR{- $pz -}.EXE");

/* The second logical name we deal with, the buffer for its old value,
 * and its temporary new value
 */
const $DESCRIPTOR(lnm2, "OSSL$LIBSSL{- $sv -}_SHR{- $pz -}");
char lnm2oldbuf[256]; short lnm2oldlen = 0;
$DESCRIPTOR(lnm2old, lnm2oldbuf);
const $DESCRIPTOR(lnm2new, "{- $bldd -}OSSL$LIBSSL{- $sv -}_SHR{- $pz -}.EXE");

/* The foreign command we want to run with the logical names above set
 * to their temporary values
 */
char foreign_cmd_buf[4096]; short foreign_cmd_len = 0;
$DESCRIPTOR(foreign_cmd, foreign_cmd_buf);

int main()
{
    int status = 0;
    int lnm1status = 0, lnm2status = 0;

    /* Fetch the command line.  lib$get_foreign() is nice enough to
     * strip away the program name, thus only returning the arguments,
     * which is exactly what we need.
     */
    lib$get_foreign(&foreign_cmd, 0, &foreign_cmd_len);
    foreign_cmd.dsc$w_length = foreign_cmd_len;

#ifdef DEBUG
    foreign_cmd_buf[foreign_cmd_len] = '\0';
    printf("[%d] %s\n\n", foreign_cmd_len, foreign_cmd_buf);
#endif

    /* Fetch the first logical name value and save the status */
    lnm1status = lib$get_logical(&lnm1, &lnm1old, &lnm1oldlen,
                                 &lnm_process_table);
    if (lnm1status == SS$_NORMAL)
        lnm1old.dsc$w_length = lnm1oldlen;
    else if (lnm1status != SS$_NOLOGNAM)
        return lnm1status;

    /* Fetch the first logical name value and save the status */
    lnm2status = lib$get_logical(&lnm2, &lnm2old, &lnm2oldlen,
                                 &lnm_process_table);
    if (lnm2status == SS$_NORMAL)
        lnm2old.dsc$w_length = lnm2oldlen;
    else if (lnm2status != SS$_NOLOGNAM)
        return lnm2status;

    /* Set the temporary new values for both logical names */
    lib$set_logical(&lnm1, &lnm1new, &lnm_process_table);
    lib$set_logical(&lnm2, &lnm2new, &lnm_process_table);

    /* Execute the arguments as a command.  The better be a command! */
    status = lib$spawn(&foreign_cmd);

    /* If the logical names we set had old values, restore them.
     * Otherwise, simply delete their current values.
     */
    if (lnm1status == SS$_NORMAL)
        lib$set_logical(&lnm1, &lnm1old, &lnm_process_table);
    else
        lib$delete_logical(&lnm1, &lnm_process_table);
    if (lnm2status == SS$_NORMAL)
        lib$set_logical(&lnm2, &lnm2old, &lnm_process_table);
    else
        lib$delete_logical(&lnm2, &lnm_process_table);

    /* Return the status from the execution of the foreign command */
    return status;
}