freebsd-skq/usr.bin/truss/i386-cloudabi32.c
ed f9146e4251 Make truss work for CloudABI executables on i386.
The system call convention is different from i386 binaries running on
FreeBSD/amd64, but this is not noticeable by executables. On
FreeBSD/amd64, the vDSO already does padding of arguments and return
values to 64-bit values. On i386, it does not, meaning that system call
return values are simply stored in registers.
2017-12-21 09:21:40 +00:00

99 lines
2.9 KiB
C

/*-
* Copyright (c) 2015-2017 Nuxi, https://nuxi.nl/
*
* 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.
*
* THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``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 THE AUTHOR OR CONTRIBUTORS 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.
*/
#include <sys/cdefs.h>
__FBSDID("$FreeBSD$");
#include <sys/param.h>
#include <sys/ptrace.h>
#include <machine/psl.h>
#include <stdbool.h>
#include <stdio.h>
#include <sysdecode.h>
#include "truss.h"
static int
i386_cloudabi32_fetch_args(struct trussinfo *trussinfo, unsigned int narg)
{
struct current_syscall *cs;
struct ptrace_io_desc iorequest;
struct reg regs;
lwpid_t tid;
if (narg > 0) {
/* Fetch registers, containing the stack pointer. */
tid = trussinfo->curthread->tid;
if (ptrace(PT_GETREGS, tid, (caddr_t)&regs, 0) == -1) {
fprintf(trussinfo->outfile,
"-- CANNOT READ REGISTERS --\n");
return (-1);
}
/* Fetch arguments. */
cs = &trussinfo->curthread->cs;
iorequest.piod_op = PIOD_READ_D;
iorequest.piod_offs = (void **)regs.r_esp + 1;
iorequest.piod_addr = cs->args;
iorequest.piod_len = sizeof(cs->args[0]) * narg;
if (ptrace(PT_IO, tid, (caddr_t)&iorequest, 0) == -1 ||
iorequest.piod_len == 0)
return (-1);
}
return (0);
}
static int
i386_cloudabi32_fetch_retval(struct trussinfo *trussinfo, long *retval,
int *errorp)
{
struct reg regs;
lwpid_t tid;
tid = trussinfo->curthread->tid;
if (ptrace(PT_GETREGS, tid, (caddr_t)&regs, 0) == -1) {
fprintf(trussinfo->outfile, "-- CANNOT READ REGISTERS --\n");
return (-1);
}
retval[0] = regs.r_eax;
retval[1] = regs.r_edx;
*errorp = (regs.r_eflags & PSL_C) != 0;
return (0);
}
static struct procabi i386_cloudabi32 = {
"CloudABI ELF32",
SYSDECODE_ABI_CLOUDABI32,
i386_cloudabi32_fetch_args,
i386_cloudabi32_fetch_retval,
STAILQ_HEAD_INITIALIZER(i386_cloudabi32.extra_syscalls),
{ NULL }
};
PROCABI(i386_cloudabi32);