fpm_trace_mach.c

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    /* (c) 2007,2008 Andrei Nigmatulin */
 
#include "fpm_config.h"
 
#include <mach/mach.h>
#include <mach/mach_vm.h>
 
#include <unistd.h>
 
#include "fpm_trace.h"
#include "fpm_process_ctl.h"
#include "fpm_unix.h"
#include "zlog.h"
 
 
static mach_port_name_t target;
static vm_offset_t target_page_base;
static vm_offset_t local_page;
static mach_msg_type_number_t local_size;
 
static void fpm_mach_vm_deallocate(void)
{
    if (local_page) {
        mach_vm_deallocate(mach_task_self(), local_page, local_size);
        target_page_base = 0;
        local_page = 0;
        local_size = 0;
    }
}
 
static int fpm_mach_vm_read_page(vm_offset_t page) /* {{{ */
{
    kern_return_t kr;
 
    kr = mach_vm_read(target, page, fpm_pagesize, &local_page, &local_size);
    if (kr != KERN_SUCCESS) {
        zlog(ZLOG_ERROR, "failed to read vm page: mach_vm_read(): %s (%d)", mach_error_string(kr), kr);
        return -1;
    }
    return 0;
}
/* }}} */
 
int fpm_trace_signal(pid_t pid) /* {{{ */
{
    if (0 > fpm_pctl_kill(pid, FPM_PCTL_STOP)) {
        zlog(ZLOG_SYSERROR, "failed to send SIGSTOP to %d", pid);
        return -1;
    }
    return 0;
}
/* }}} */
 
int fpm_trace_ready(pid_t pid) /* {{{ */
{
    kern_return_t kr;
 
    kr = task_for_pid(mach_task_self(), pid, &target);
    if (kr != KERN_SUCCESS) {
        char *msg = "";
 
        if (kr == KERN_FAILURE) {
            msg = " It seems that master process does not have enough privileges to trace processes.";
        }
        zlog(ZLOG_ERROR, "task_for_pid() failed: %s (%d)%s", mach_error_string(kr), kr, msg);
        return -1;
    }
    return 0;
}
/* }}} */
 
int fpm_trace_close(pid_t pid) /* {{{ */
{
    fpm_mach_vm_deallocate();
    target = 0;
    return 0;
}
/* }}} */
 
int fpm_trace_get_long(long addr, long *data) /* {{{ */
{
    size_t offset = ((uintptr_t) (addr) % fpm_pagesize);
    vm_offset_t base = (uintptr_t) (addr) - offset;
 
    if (base != target_page_base) {
        fpm_mach_vm_deallocate();
        if (0 > fpm_mach_vm_read_page(base)) {
            return -1;
        }
    }
    *data = * (long *) (local_page + offset);
    return 0;
}
/* }}} */