root/sapi/fpm/fpm/fpm_trace_ptrace.c

DEFINITIONS

1. fpm_trace_signal
2. fpm_trace_ready
3. fpm_trace_close
4. fpm_trace_get_long

        /* $Id: fpm_trace_ptrace.c,v 1.7 2008/09/18 23:34:11 anight Exp $ */
        /* (c) 2007,2008 Andrei Nigmatulin */

#include "fpm_config.h"

#include <sys/wait.h>
#include <sys/ptrace.h>
#include <unistd.h>
#include <errno.h>

#if defined(PT_ATTACH) && !defined(PTRACE_ATTACH)
#define PTRACE_ATTACH PT_ATTACH
#endif

#if defined(PT_DETACH) && !defined(PTRACE_DETACH)
#define PTRACE_DETACH PT_DETACH
#endif

#if defined(PT_READ_D) && !defined(PTRACE_PEEKDATA)
#define PTRACE_PEEKDATA PT_READ_D
#endif

#include "fpm_trace.h"
#include "zlog.h"

static pid_t traced_pid;

int fpm_trace_signal(pid_t pid) /* {{{ */
{
        if (0 > ptrace(PTRACE_ATTACH, pid, 0, 0)) {
                zlog(ZLOG_SYSERROR, "failed to ptrace(ATTACH) child %d", pid);
                return -1;
        }
        return 0;
}
/* }}} */

int fpm_trace_ready(pid_t pid) /* {{{ */
{
        traced_pid = pid;
        return 0;
}
/* }}} */

int fpm_trace_close(pid_t pid) /* {{{ */
{
        if (0 > ptrace(PTRACE_DETACH, pid, (void *) 1, 0)) {
                zlog(ZLOG_SYSERROR, "failed to ptrace(DETACH) child %d", pid);
                return -1;
        }
        traced_pid = 0;
        return 0;
}
/* }}} */

int fpm_trace_get_long(long addr, long *data) /* {{{ */
{
#ifdef PT_IO
        struct ptrace_io_desc ptio = {
                .piod_op = PIOD_READ_D,
                .piod_offs = (void *) addr,
                .piod_addr = (void *) data,
                .piod_len = sizeof(long)
        };

        if (0 > ptrace(PT_IO, traced_pid, (void *) &ptio, 0)) {
                zlog(ZLOG_SYSERROR, "failed to ptrace(PT_IO) pid %d", traced_pid);
                return -1;
        }
#else
        errno = 0;
        *data = ptrace(PTRACE_PEEKDATA, traced_pid, (void *) addr, 0);
        if (errno) {
                zlog(ZLOG_SYSERROR, "failed to ptrace(PEEKDATA) pid %d", traced_pid);
                return -1;
        }
#endif
        return 0;
}
/* }}} */