freebsd-skq/usr.bin/doscmd/exe.c
2002-03-07 12:52:27 +00:00

422 lines
9.8 KiB
C

/*
* Copyright (c) 1992, 1993, 1996
* Berkeley Software Design, Inc. All rights reserved.
*
* 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. All advertising materials mentioning features or use of this software
* must display the following acknowledgement:
* This product includes software developed by Berkeley Software
* Design, Inc.
*
* THIS SOFTWARE IS PROVIDED BY Berkeley Software Design, Inc. ``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 Berkeley Software Design, Inc. 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.
*
* BSDI exe.c,v 2.2 1996/04/08 19:32:34 bostic Exp
*/
#include <sys/cdefs.h>
__FBSDID("$FreeBSD$");
#include <sys/types.h>
#include <sys/uio.h>
#include <ctype.h>
#include <stdio.h>
#include <stdlib.h>
#include <unistd.h>
#include "doscmd.h"
/* exports */
int pspseg;
int curpsp = 0;
/* locals */
static int psp_s[10] = { 0 };
static int env_s[10];
static regcontext_t frames[10];
static int
make_environment(char *cmd_name, char **env)
{
int i;
int total;
int len;
int envseg;
char *p;
char *env_block;
total = 0;
for (i = 0; env[i]; i++) {
debug (D_EXEC,"env: %s\n", env[i]);
len = strlen(env[i]);
if (total + len >= 32 * 1024)
break;
total += len + 1;
}
total++; /* terminating null */
total += 2; /* word count */
total += strlen(cmd_name) + 1;
total += 4; /* some more zeros, just in case */
if ((envseg = mem_alloc(total/16 + 1, 1, NULL)) == 0)
fatal("out of memory for env\n");
env_block = (char *)MAKEPTR(envseg, 0);
memset (env_block, 0, total);
p = env_block;
total = 0;
for (i = 0; env[i]; i++) {
len = strlen(env[i]);
if (total + len >= 32 * 1024)
break;
total += len + 1;
strcpy (p, env[i]);
p += strlen(p) + 1;
}
*p++ = 0;
*(short *)p = strlen(cmd_name);
p += 2;
strcpy (p, cmd_name);
while(*p) {
if (*p == '/')
*p = '\\';
else if (islower(*p))
*p = toupper(*p);
p++;
}
*p = '\0';
return(envseg);
}
static void
load_com(int fd, int start_segment)
{
char *start_addr;
int i;
start_addr = (char *)MAKEPTR(start_segment, 0);
lseek (fd, 0, 0);
i = read (fd, start_addr, 0xff00);
debug(D_EXEC, "Read %05x into %04x\n",
i, start_segment);
}
static void
load_exe(int fd, int start_segment, int reloc_segment __unused, struct exehdr *hdr, int text_size)
{
char *start_addr;
int reloc_size;
struct reloc_entry *reloc_tbl, *rp;
u_short *segp;
int i;
start_addr = (char *)MAKEPTR(start_segment, 0);
lseek (fd, hdr->hdr_size * 16, 0);
if (read (fd, start_addr, text_size) != text_size)
fatal ("error reading program text\n");
debug(D_EXEC, "Read %05x into %04x\n",
text_size, start_segment);
if (hdr->nreloc) {
reloc_size = hdr->nreloc * sizeof (struct reloc_entry);
if ((reloc_tbl = (struct reloc_entry *)malloc (reloc_size)) == NULL)
fatal ("out of memory for program\n");
lseek (fd, hdr->reloc_offset, 0);
if (read (fd, reloc_tbl, reloc_size) != reloc_size)
fatal ("error reading reloc table\n");
for (i = 0, rp = reloc_tbl; i < hdr->nreloc; i++, rp++) {
segp = (u_short *)MAKEPTR(start_segment + rp->seg, rp->off);
*segp += start_segment;
}
free((char *)reloc_tbl);
}
}
void
load_command(regcontext_t *REGS, int run, int fd, char *cmd_name,
u_short *param, char **argv, char **envs)
{
struct exehdr hdr;
int min_memory, max_memory;
int biggest;
int envseg;
char *psp;
int text_size;
int i;
int start_segment;
int exe_file;
char *p;
int used, n;
char *fcb;
int newpsp;
u_short init_cs, init_ip, init_ss, init_sp, init_ds, init_es;
if (envs)
envseg = make_environment(cmd_name, envs);
else
envseg = env_s[curpsp];
/* read exe header */
if (read (fd, &hdr, sizeof hdr) != sizeof hdr)
fatal ("can't read header\n");
/* proper header ? */
if (hdr.magic == 0x5a4d) {
exe_file = 1;
text_size = (hdr.size - 1) * 512 + hdr.bytes_on_last_page
- hdr.hdr_size * 16;
min_memory = hdr.min_memory + (text_size + 15)/16;
max_memory = hdr.max_memory + (text_size + 15)/16;
} else {
exe_file = 0;
min_memory = 64 * (1024/16);
max_memory = 0xffff;
}
/* alloc mem block */
pspseg = mem_alloc(max_memory, 1, &biggest);
if (pspseg == 0) {
if (biggest < min_memory ||
(pspseg = mem_alloc(biggest, 1, NULL)) == 0)
fatal("not enough memory: needed %d have %d\n",
min_memory, biggest);
max_memory = biggest;
}
mem_change_owner(pspseg, pspseg);
mem_change_owner(envseg, pspseg);
/* create psp */
newpsp = curpsp + 1;
psp_s[newpsp] = pspseg;
env_s[newpsp] = envseg;
psp = (char *)MAKEPTR(pspseg, 0);
memset(psp, 0, 256);
psp[0] = 0xcd;
psp[1] = 0x20;
*(u_short *)&psp[2] = pspseg + max_memory;
/*
* this is supposed to be a long call to dos ... try to fake it
*/
psp[5] = 0xcd;
psp[6] = 0x99;
psp[7] = 0xc3;
*(u_short *)&psp[0x16] = psp_s[curpsp];
psp[0x18] = 1;
psp[0x19] = 1;
psp[0x1a] = 1;
psp[0x1b] = 0;
psp[0x1c] = 2;
memset(psp + 0x1d, 0xff, 15);
*(u_short *)&psp[0x2c] = envseg;
*(u_short *)&psp[0x32] = 20;
*(u_long *)&psp[0x34] = MAKEVEC(pspseg, 0x18);
*(u_long *)&psp[0x38] = 0xffffffff;
psp[0x50] = 0xcd;
psp[0x51] = 0x98;
psp[0x52] = 0xc3;
p = psp + 0x81;
*p = 0;
used = 0;
for (i = 0; argv[i]; i++) {
n = strlen(argv[i]);
if (used + 1 + n > 0x7d)
break;
*p++ = ' ';
memcpy(p, argv[i], n);
p += n;
used += n;
}
psp[0x80] = strlen(psp + 0x81);
psp[0x81 + psp[0x80]] = 0x0d;
psp[0x82 + psp[0x80]] = 0;
p = psp + 0x81;
parse_filename(0x00, p, psp + 0x5c, &n);
p += n;
parse_filename(0x00, p, psp + 0x6c, &n);
if (param[4]) {
fcb = (char *)MAKEPTR(param[4], param[3]);
memcpy(psp + 0x5c, fcb, 16);
}
if (param[6]) {
fcb = (char *)MAKEPTR(param[6], param[5]);
memcpy(psp + 0x6c, fcb, 16);
}
#if 0
printf("005c:");
for (n = 0; n < 16; n++)
printf(" %02x", psp[0x5c + n]);
printf("\n");
printf("006c:");
for (n = 0; n < 16; n++)
printf(" %02x", psp[0x6c + n]);
printf("\n");
#endif
disk_transfer_addr = MAKEVEC(pspseg, 0x80);
start_segment = pspseg + 0x10;
if (!exe_file) {
load_com(fd, start_segment);
init_cs = pspseg;
init_ip = 0x100;
init_ss = init_cs;
init_sp = 0xfffe;
init_ds = init_cs;
init_es = init_cs;
} else {
load_exe(fd, start_segment, start_segment, &hdr, text_size);
init_cs = hdr.init_cs + start_segment;
init_ip = hdr.init_ip;
init_ss = hdr.init_ss + start_segment;
init_sp = hdr.init_sp;
init_ds = pspseg;
init_es = init_ds;
}
debug(D_EXEC, "cs:ip = %04x:%04x, ss:sp = %04x:%04x, "
"ds = %04x, es = %04x\n",
init_cs, init_ip, init_ss, init_sp, init_ds, init_es);
if (run) {
frames[newpsp] = *REGS;
curpsp = newpsp;
R_EFLAGS = 0x20202;
R_CS = init_cs;
R_IP = init_ip;
R_SS = init_ss;
R_SP = init_sp;
R_DS = init_ds;
R_ES = init_es;
R_AX = R_BX = R_CX = R_DX = R_SI = R_DI = R_BP = 0;
} else {
param[7] = init_sp;
param[8] = init_ss;
param[9] = init_ip;
param[10] = init_cs;
}
}
void
load_overlay(int fd, int start_segment, int reloc_segment)
{
struct exehdr hdr;
int text_size;
int exe_file;
/* read exe header */
if (read (fd, &hdr, sizeof hdr) != sizeof hdr)
fatal ("can't read header\n");
/* proper header ? */
if (hdr.magic == 0x5a4d) {
exe_file = 1;
text_size = (hdr.size - 1) * 512 + hdr.bytes_on_last_page
- hdr.hdr_size * 16;
} else {
exe_file = 0;
}
if (!exe_file)
load_com(fd, start_segment);
else
load_exe(fd, start_segment, reloc_segment, &hdr, text_size);
}
int
get_env(void)
{
return(env_s[curpsp]);
}
void
exec_command(regcontext_t *REGS, int run,
int fd, char *cmd_name, u_short *param)
{
char *arg;
char *env;
char *argv[2];
char *envs[100];
env = (char *)MAKEPTR(param[0], 0);
arg = (char *)MAKEPTR(param[2], param[1]);
if (arg) {
int nbytes = *arg++;
arg[nbytes] = 0;
if (!*arg)
arg = NULL;
}
argv[0] = arg;
argv[1] = NULL;
debug (D_EXEC, "exec_command: cmd_name = %s\n"
"env = 0x0%x, arg = %04x:%04x(%s)\n",
cmd_name, param[0], param[2], param[1], arg);
if (env) {
int i;
for ( i=0; i < 99 && *env; ++i ) {
envs[i] = env;
env += strlen(env)+1;
}
envs[i] = NULL;
load_command(REGS, run, fd, cmd_name, param, argv, envs);
} else
load_command(REGS, run, fd, cmd_name, param, argv, NULL);
}
void
exec_return(regcontext_t *REGS, int code)
{
debug(D_EXEC, "Returning from exec\n");
mem_free_owner(psp_s[curpsp]);
*REGS = frames[curpsp--];
R_AX = code;
R_FLAGS &= ~PSL_C; /* It must have worked */
}