m-template

unix系统下top命令的源代码

/*
 * top - a top users display for Unix
 *
 * THIS IS A TEMPLATE FILE FOR A MACHINE DEPENDENT (m_...c) FILE
 *
 * SYNOPSIS:  one line description of machine this module works with
 *
 * DESCRIPTION:
 * Detailed description of this machine dependent module.
 * It can be multiple lines, but a blank comment line (one with only an
 * asterisk) is considered to end it.  Place here a complete list of 
 * the machines and OS versions that this module works on.
 *
 * LIBS:  list of special libraries to include at link step (REMOVE THIS LINE IF NOT NEEDED)
 *
 * AUTHOR:  your name and <[e-mail]>
 */

#include "top.h"
#include "machine.h"


/*
 *  These definitions control the format of the per-process area
 */

static char header[] =
  "  PID X        PRI NICE   SIZE   RES STATE   TIME   WCPU    CPU COMMAND";
/* 0123456   -- field to fill in starts at header+6 */
#define UNAME_START 6

#define Proc_format \
	"%5d %-8.8s %3d %4d%6dK %4dK %-5s%4d:%02d %5.2f%% %5.2f%% %.14s"

/* these are for detailing the process states */

int process_states[?];
char *procstatenames[] = {
    "", " sleeping, ", " ABANDONED, ", " running, ", " starting, ",
    " zombie, ", " stopped, ",
    NULL
};

/* these are for detailing the cpu states */

int cpu_states[?];
char *cpustatenames[] = {
    "user", "nice", "system", "idle",
    NULL
};

/* these are for detailing the memory statistics */

int memory_stats[?];
char *memorynames[] = {
    "K available, ", "K in use, ", "K free, ", "K locked", NULL
};

/* useful externals */
extern int errno;
extern char *sys_errlist[];

long lseek();
long time();
long percentages();

machine_init(statics)

struct statics *statics;

{
    return(0);
}

char *format_header(uname_field)

register char *uname_field;

{
    register char *ptr;

    ptr = header + UNAME_START;
    while (*uname_field != '\0')
    {
	*ptr++ = *uname_field++;
    }

    return(header);
}

get_system_info(si)

struct system_info *si;

{
}

static struct handle handle;

caddr_t get_process_info(si, sel, compare)

struct system_info *si;
struct process_select *sel;
int (*compare)();

{
    return((caddr_t)&handle);
}

char fmt[128];		/* static area where result is built */

/* define what weighted cpu is.  */
#define weighted_cpu(pct, pp) ((pp)->p_time == 0 ? 0.0 : \
			 ((pct) / (1.0 - exp((pp)->p_time * logcpu))))

char *format_next_process(handle, get_userid)

caddr_t handle;
char *(*get_userid)();

{
    return(fmt);
}

/*
 *  getkval(offset, ptr, size, refstr) - get a value out of the kernel.
 *	"offset" is the byte offset into the kernel for the desired value,
 *  	"ptr" points to a buffer into which the value is retrieved,
 *  	"size" is the size of the buffer (and the object to retrieve),
 *  	"refstr" is a reference string used when printing error meessages,
 *	    if "refstr" starts with a '!', then a failure on read will not
 *  	    be fatal (this may seem like a silly way to do things, but I
 *  	    really didn't want the overhead of another argument).
 *  	
 */

getkval(offset, ptr, size, refstr)

unsigned long offset;
int *ptr;
int size;
char *refstr;

{
    if (kvm_read(kd, offset, ptr, size) != size)
    {
	if (*refstr == '!')
	{
	    return(0);
	}
	else
	{
	    fprintf(stderr, "top: kvm_read for %s: %s\n",
		refstr, sys_errlist[errno]);
	    quit(23);
	}
    }
    return(1);
}
    
/* comparison routine for qsort */
/* NOTE: this is specific to the BSD proc structure, but it should
   give you a good place to start. */

/*
 *  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			*/
};
 
proc_compare(pp1, pp2)

struct proc **pp1;
struct proc **pp2;

{
    register struct proc *p1;
    register struct proc *p2;
    register int result;
    register pctcpu lresult;

    /* remove one level of indirection */
    p1 = *pp1;
    p2 = *pp2;

    /* compare percent cpu (pctcpu) */
    if ((lresult = p2->p_pctcpu - p1->p_pctcpu) == 0)
    {
	/* use cpticks to break the tie */
	if ((result = p2->p_cpticks - p1->p_cpticks) == 0)
	{
	    /* use process state to break the tie */
	    if ((result = sorted_state[p2->p_stat] -
			  sorted_state[p1->p_stat])  == 0)
	    {
		/* use priority to break the tie */
		if ((result = p2->p_pri - p1->p_pri) == 0)
		{
		    /* use resident set size (rssize) to break the tie */
		    if ((result = p2->p_rssize - p1->p_rssize) == 0)
		    {
			/* use total memory to break the tie */
			result = PROCSIZE(p2) - PROCSIZE(p1);
		    }
		}
	    }
	}
    }
    else
    {
	result = lresult < 0 ? -1 : 1;
    }

    return(result);
}

proc_owner(pid)

int pid;

{
   /* returns uid of owner of process pid */
   return(uid);
}