m_macosx.c

unix系统下top命令的源代码

		 * first, we set the pointer to the reference in
		 * the kproc list.
		 */
		
		proc_list[i].kproc = pp2;

		/*
		 * then, we load all of the task info for the process
		 */

		if(PP(pp2, p_stat) != SZOMB)
			{
			rc = task_by_unix_pid(task_self(), 
				PP(pp2, p_pid), 
				&(proc_list[i].the_task));

			if(rc != KERN_SUCCESS)
				{
				puke("error:  get task info for pid %d failed with rc = %d", PP(pp2, p_pid), rc);
				}

			/*
			 * load the task information
			 */

			rc = task_info(proc_list[i].the_task, TASK_BASIC_INFO, 
				(task_info_t)&(proc_list[i].task_info),
				&info_count);

			if(rc != KERN_SUCCESS)
				{
				puke("error:  couldn't get task info (%s); rc = %d", strerror(errno), rc);
				}

			/*
			 * load the thread summary information
			 */

			load_thread_info(&proc_list[i]);
			}
		}

	/* get a pointer to the states summary array */
	si->procstates = process_states;

	/* set up flags which define what we are going to select */
	show_idle = sel->idle;
	show_system = sel->system;
	show_uid = sel->uid != -1;
	show_command = sel->command != NULL;

	/* count up process states and get pointers to interesting procs */
	total_procs = 0;
	active_procs = 0;
	memset((char *)process_states, 0, sizeof(process_states));
	prefp = proc_ref;
	for(pp = proc_list, i = 0; i < nproc; pp++, i++)
		{
		/*
		 *  Place pointers to each valid proc structure in 
		 * proc_ref[].  Process slots that are actually in use 
		 * have a non-zero status field.  Processes with
		 * P_SYSTEM set are system processes---these get 
		 * ignored unless show_sysprocs is set.
		 */
		if(MPP(pp, p_stat) != 0 && 
				(show_system || ((MPP(pp, p_flag) & P_SYSTEM) == 0)))
			{
			total_procs++;
			process_states[(unsigned char) MPP(pp, p_stat)]++;
			if((MPP(pp, p_stat) != SZOMB) &&
					(show_idle || (MPP(pp, p_pctcpu) != 0) || 
			 		(MPP(pp, p_stat) == SRUN)) &&
					(!show_uid || MEP(pp, e_pcred.p_ruid) == (uid_t)sel->uid))
				{
				*prefp++ = pp;
				active_procs++;
				}
			}
		}
	
	/* 
	 * if requested, sort the "interesting" processes
	 */

	if(compare != NULL)
		qsort((char *)proc_ref, active_procs, sizeof(struct macos_proc *), compare);

	/* remember active and total counts */
	si->p_total = total_procs;
	si->p_active = pref_len = active_procs;

	/* pass back a handle */
	handle.next_proc = proc_ref;
	handle.remaining = active_procs;
	return((caddr_t)&handle);
}

/*
 * get_system_info()
 *
 * This function is responsible for geting the periodic
 * system information snapshot.
 */

int get_system_info(struct system_info *si)
{
	register long	total;
	register int	i;

	/*
	 * get the cp_time array
	 */

	if(!kread(nlst[X_CP_TIME].n_value, cp_time,
			sizeof(cp_time), nlst[X_CP_TIME].n_name))
		return(0);

#ifdef MAX_VERBOSE

	/*
	 * print out the entries
	 */

	for(i = 0; i < CPUSTATES; i++)
		printf("cp_time[%d] = %d\n", i, cp_time[i]);

#endif /* MAX_VERBOSE */

	/*
	 * get the load averages
	 */

	if(kvm_getloadavg(kd, si->load_avg, NUM_AVERAGES) == -1)
		{
		puke("error:  kvm_getloadavg() failed (%s)", strerror(errno));
		return(0);
		}

#ifdef MAX_VERBOSE
	printf("%-30s%03.2f, %03.2f, %03.2f\n", 
			"load averages:", 
			si->load_avg[0],
			si->load_avg[1],
			si->load_avg[2]);
#endif /* MAX_VERBOSE */

	total = percentages(CPUSTATES, cpu_states, cp_time, cp_old, cp_diff);
	/*
	 * get the memory statistics
	 */

	{
		kern_return_t	status;
		status = vm_statistics(task_self(), &vm_stats);

		if(status != KERN_SUCCESS)
			{
			puke("error:  vm_statistics() failed (%s)", strerror(errno));
			return(0);
			}

		/*
		 * we already have the total memory, we just need
		 * to get it in the right format.
		 */

		memory_stats[0] = pagetok(maxmem / vm_stats.pagesize);
		memory_stats[1] = pagetok(vm_stats.free_count);
		memory_stats[2] = pagetok(vm_stats.active_count);
		memory_stats[3] = pagetok(vm_stats.inactive_count);
		memory_stats[4] = pagetok(vm_stats.wire_count);

		if(swappgsin < 0)
			{
			memory_stats[5] = 1;
			memory_stats[6] = 1;
			}
		else
			{
			memory_stats[5] = pagetok(((vm_stats.pageins - swappgsin)));
			memory_stats[6] = pagetok(((vm_stats.pageouts - swappgsout)));
			}
		swappgsin = vm_stats.pageins;
		swappgsout = vm_stats.pageouts;
	}
	
	si->cpustates = cpu_states;
	si->memory = memory_stats;
	si->last_pid = -1;

	return(1);
}

/*
 * machine_init()
 *
 * This function is responsible for filling in the values of the
 * statics structure.
 */

int machine_init(struct statics *stat)
{
	register int rc = 0;
	register int i = 0;
//	register int pagesize;

	/*
	 * open the kernel
	 */

	if((kd = kvm_open(VMUNIX, MEM, SWAP, O_RDONLY, "kvm_open")) == NULL)
		{
		puke("error:  couldn't open kernel (%s)", strerror(errno));
		return(0);
		}

	/*
	 * turn off super-user privs
	 */

//	seteuid(getuid());

	/*
	 * read the nlist we need
	 */
	
	rc = kvm_nlist(kd, nlst);
	if(rc == -1)
		{
		puke("error:  unable to read kernel table (%s)", strerror(errno));
		return(0);
		}

	if(rc > 0)
		{
		puke("error:  kvm_nlist() found %d invalid entries.\n", rc);
		return(0);
		}

#ifdef MAX_VERBOSE

	/*
	 * print out the entries
	 */

	for(i = 0; i < NLIST_LAST; i++)
		{
		printf("symbol %10s is type 0x%02X at offset 0x%02X\n", 
			nlst[i].n_name, 
			nlst[i].n_type & N_TYPE, 
			nlst[i].n_value);
		}

#endif /* MAX_VERBOSE */

	/*
	 * next, we get the data for the names
	 *
	 * get max number of processes
	 */

	if(!kread(nlst[X_NPROC].n_value, &nproc,
			sizeof(nproc), nlst[X_NPROC].n_name))
		return(0);

#ifdef MAX_VERBOSE
	printf("%-30s%10d\n", "max number of processes:", nproc);
#endif /* MAX_VERBOSE */

	/*
	 * get clock rate
	 */

	if(!kread(nlst[X_HZ].n_value, &hz,
			sizeof(hz), nlst[X_HZ].n_name))
		return(0);

#ifdef MAX_VERBOSE
	printf("%-30s%10d\n", "clock rate:", hz);
#endif /* MAX_VERBOSE */

	/*
	 * get memory size
	 */

	if(!kread(nlst[X_MAXMEM].n_value, &maxmem,
			sizeof(maxmem), nlst[X_MAXMEM].n_name))
		return(0);

#ifdef MAX_VERBOSE
	printf("%-30s%10d\n", "total system memory:", maxmem);
#endif /* MAX_VERBOSE */

	/*
	 * calculate the pageshift from the system page size
	 */

	pagesize = getpagesize();
	pageshift = 0;
	while((pagesize >>= 1) > 0)
		pageshift++;

	pageshift -= LOG1024;

	/*
	 * fill in the statics information
	 */

	stat->procstate_names = procstates;
	stat->cpustate_names = cpustates;
	stat->memory_names = memnames;

	return(0);
}

/* comparison routine for qsort */

/*
 *  proc_compare - comparison function for "qsort"
 *	Compares the resource consumption of two processes using five
 *  	distinct keys.  The keys (in descending order of importance) are:
 *  	percent cpu, cpu ticks, state, resident set size, total virtual
 *  	memory usage.  The process states are ordered as follows (from least
 *  	to most important):  WAIT, zombie, sleep, stop, start, run.  The
 *  	array declaration below maps a process state index into a number
 *  	that reflects this ordering.
 */

static unsigned char sorted_state[] =
{
    0,	/* not used		*/
    3,	/* sleep		*/
    1,	/* ABANDONED (WAIT)	*/
    6,	/* run			*/
    5,	/* start		*/
    2,	/* zombie		*/
    4	/* stop			*/
};
 
int proc_compare(struct macos_proc **pp1, struct macos_proc **pp2)
{
    register struct macos_proc *p1;
    register struct macos_proc *p2;
    register int result;
    register pctcpu lresult;

    /* remove one level of indirection */
    p1 = *(struct macos_proc **) pp1;
    p2 = *(struct macos_proc **) pp2;

    /* compare percent cpu (pctcpu) */
    if ((lresult = RP(p2, cpu_usage) - RP(p1, cpu_usage)) == 0)
    {
	/* use cpticks to break the tie */
	if ((result = MPP(p2, p_cpticks) - MPP(p1, p_cpticks)) == 0)
	{
	    /* use process state to break the tie */
	    if ((result = sorted_state[(unsigned char) MPP(p2, p_stat)] -
			  sorted_state[(unsigned char) MPP(p1, p_stat)])  == 0)
	    {
		/* use priority to break the tie */
		if ((result = MPP(p2, p_priority) - MPP(p1, p_priority)) == 0)
		{
		    /* use resident set size (rssize) to break the tie */
		    if ((result = MVP(p2, vm_rssize) - MVP(p1, vm_rssize)) == 0)
		    {
			/* use total memory to break the tie */
			result = PROCSIZE(p2->kproc) - PROCSIZE(p1->kproc);
		    }
		}
	    }
	}
    }
    else
    {
	result = lresult < 0 ? -1 : 1;
    }

    return(result);
}


/*
 * proc_owner(pid) - returns the uid that owns process "pid", or -1 if
 *		the process does not exist.
 *		It is EXTREMLY IMPORTANT that this function work correctly.
 *		If top runs setuid root (as in SVR4), then this function
 *		is the only thing that stands in the way of a serious
 *		security problem.  It validates requests for the "kill"
 *		and "renice" commands.
 */

int proc_owner(pid)

int pid;

{
    register int cnt;
    register struct macos_proc **prefp;
    register struct macos_proc *pp;

    prefp = proc_ref;
    cnt = pref_len;
    while (--cnt >= 0)
    {
	pp = *prefp++;	
	if (MPP(pp, p_pid) == (pid_t)pid)
	{
	    return((int)MEP(pp, e_pcred.p_ruid));
	}
    }
    return(-1);
}

/*
 * load_thread_info()
 *
 * This function will attempt to load the thread summary info
 * for a Mach task.  The task is located as part of the macos_proc
 * structure.
 *
 * returns the kern_return_t value of any failed call or KERN_SUCCESS
 * if everything works.
 */

int load_thread_info(struct macos_proc *mp)
{
	register kern_return_t		rc = 0;
	register int			i = 0;
	register int			t_utime = 0;
	register int			t_stime = 0;
	register int			t_cpu = 0;
	register int			t_state = 0;
	register task_t			the_task = mp->the_task;

	thread_array_t			thread_list = NULL;

	/*
	 * We need to load all of the threads for the 
	 * given task so we can get the performance 
	 * data from them.
	 */

	mp->thread_count = 0;
	rc = task_threads(the_task, &thread_list, &(mp->thread_count));

	if(rc != KERN_SUCCESS)
		{
//		puke("error:  unable to load threads for task (%s); rc = %d", strerror(errno), rc);
		return(rc);
		}

	/*
	 * now, for each of the threads, we need to sum the stats
	 * so we can present the whole thing to the caller.
	 */

	for(i = 0; i < mp->thread_count; i++)
		{
		struct thread_basic_info	t_info;
		int				icount = THREAD_BASIC_INFO_COUNT;
		kern_return_t			rc = 0;

		rc = thread_info(thread_list[i], THREAD_BASIC_INFO, 
				(thread_info_t)&t_info, &icount);

		if(rc != KERN_SUCCESS)
			{
			puke("error:  unable to load thread info for task (%s); rc = %d", strerror(errno), rc);
			return(rc);
			}

		t_utime += t_info.user_time.seconds;
		t_stime += t_info.system_time.seconds;
		t_cpu += t_info.cpu_usage;
		}

	vm_deallocate(task_self(), (vm_address_t)thread_list, sizeof(thread_array_t)*(mp->thread_count));

	/*
	 * Now, we load the values in the structure above.
	 */

	RP(mp, user_time).seconds = t_utime;
	RP(mp, system_time).seconds = t_stime;
	RP(mp, cpu_usage) = t_cpu;

	return(KERN_SUCCESS);
}