/*
 * top - a top users display for Unix
 *
 * SYNOPSIS:  any hp9000 running hpux version 10.x
 *
 * DESCRIPTION:
 * This is the machine-dependent module for HPUX 10 that uses pstat.
 * It has not been tested on HPUX 10.1.
 * This makes top work on (at least) the following systems:
 *	hp9000s800
 * This may make top work on the following, but we aren't sure:
 *	hp9000s700
 *	hp9000s300
 *
 * CFLAGS: -DHAVE_GETOPT
 *
 * LIBS: 
 *
 * AUTHOR: Rich Holland <holland@synopsys.com>
 * AUTHOR: adapted from Kevin Schmidt <kevin@mcl.ucsb.edu> 
 */

#include <sys/types.h>
#include <sys/signal.h>
#include <sys/param.h>

#include <stdio.h>
#include <errno.h>
#include <nlist.h>
#include <math.h>
#include <sys/dir.h>
#include <sys/dk.h>
#include <sys/vm.h>
#include <sys/file.h>
#include <sys/time.h>
#include <sys/pstat.h>

# define P_RSSIZE(p) (p)->pst_rssize
# define P_TSIZE(p) (p)->pst_tsize
# define P_DSIZE(p) (p)->pst_dsize
# define P_SSIZE(p) (p)->pst_ssize

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

#define VMUNIX	"/stand/vmunix"
#define KMEM	"/dev/kmem"
#define MEM	"/dev/mem"
#ifdef DOSWAP
#define SWAP	"/dev/dmem"
#endif

/* get_process_info passes back a handle.  This is what it looks like: */

struct handle
{
    struct pst_status **next_proc;	/* points to next valid pst pointer */
    int remaining;		/* number of pointers remaining */
};

/* declarations for load_avg */
#include "loadavg.h"

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

/* what we consider to be process size: */
#define PROCSIZE(pp) (P_TSIZE(pp) + P_DSIZE(pp) + P_SSIZE(pp))

/* definitions for indices in the nlist array */
#define X_AVENRUN	0
#define X_CCPU		1
#define X_NPROC		2
#define X_PROC		3
#define X_TOTAL		4
#define X_CP_TIME	5
#define X_MPID		6

/*
 * Steinar Haug from University of Trondheim, NORWAY pointed out that 
 * the HP 9000 system 800 doesn't have _hz defined in the kernel.  He
 * provided a patch to work around this.  We've improved on this patch
 * here and set the constant X_HZ only when _hz is available in the
 * kernel.  Code in this module that uses X_HZ is surrounded with
 * appropriate ifdefs.
 */

#ifndef hp9000s300
#define X_HZ		7
#endif


static struct nlist nlst[] = {
    { "_avenrun" },		/* 0 */
    { "_cexp" },		/* 1 */
    { "_nproc" },		/* 2 */
    { "_proc" },		/* 3 */
    { "_total" },		/* 4 */
    { "_cp_time" },		/* 5 */
    { "_mpid" },		/* 6 */
#ifdef X_HZ
    { "_hz" },			/* 7 */
#endif
    { 0 }
};

/*
 *  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 %5s %5s %-5s %6s %5.2f%% %5.2f%% %s"

/* process state names for the "STATE" column of the display */

char *state_abbrev[] =
{
    "", "sleep", "run", "stop", "zomb", "trans", "start"
};


static int kmem;

/* values that we stash away in _init and use in later routines */

static double logcpu;

/* these are retrieved from the kernel in _init */

static unsigned long proc;
static          int  nproc;
static          long hz;
static load_avg  ccpu;
static          int  ncpu = 0;

/* these are offsets obtained via nlist and used in the get_ functions */
static unsigned long mpid_offset;
static unsigned long avenrun_offset;
static unsigned long total_offset;
static unsigned long cp_time_offset;

/* these are for calculating cpu state percentages */

static long cp_time[CPUSTATES];
static long cp_old[CPUSTATES];
static long cp_diff[CPUSTATES];

/* these are for detailing the process states */

int process_states[7];
char *procstatenames[] = {
    "", " sleeping, ", " running, ", " stopped, ", " zombie, ",
    " trans, ", " starting, ",
    NULL
};

/* these are for detailing the cpu states */

int cpu_states[9];
char *cpustatenames[] = {
    "usr", "nice", "sys", "idle", "", "", "", "intr", "ker",
    NULL
};

/* these are for detailing the memory statistics */

int memory_stats[8];
char *memorynames[] = {
    "Real: ", "K/", "K act/tot  ", "Virtual: ", "K/",
    "K act/tot  ", "Free: ", "K", NULL
};

/* these are for keeping track of the pst array */

static int bytes;
static int pref_len;
static struct pst_status *pbase;
static struct pst_status **pref;

/* these are for getting the memory statistics */

static int pageshift;		/* log base 2 of the pagesize */

/* define pagetok in terms of pageshift */

#define pagetok(size) ((size) << pageshift)

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

long lseek();
long time();

machine_init(statics)

struct statics *statics;

{
    register int i = 0;
    register int pagesize;

    if ((kmem = open(KMEM, O_RDONLY)) == -1) {
	perror(KMEM);
	return(-1);
    }
#ifdef hp9000s800
    /* 800 names don't have leading underscores */
    for (i = 0; nlst[i].n_name; nlst[i++].n_name++)
	continue;
#endif

    /* get the list of symbols we want to access in the kernel */
    (void) nlist(VMUNIX, nlst);
    if (nlst[0].n_type == 0)
    {
	fprintf(stderr, "top: nlist failed\n");
	return(-1);
    }

    /* make sure they were all found */
    if (check_nlist(nlst) > 0)
    {
	return(-1);
    }

    /* get the symbol values out of kmem */
    (void) getkval(nlst[X_PROC].n_value,   (int *)(&proc),	sizeof(proc),
	    nlst[X_PROC].n_name);
    (void) getkval(nlst[X_NPROC].n_value,  &nproc,		sizeof(nproc),
	    nlst[X_NPROC].n_name);
    (void) getkval(nlst[X_CCPU].n_value,   (int *)(&ccpu),	sizeof(ccpu),
	    nlst[X_CCPU].n_name);
#ifdef X_HZ
    (void) getkval(nlst[X_HZ].n_value,     (int *)(&hz),	sizeof(hz),
	    nlst[X_HZ].n_name);
#else
    hz = HZ;
#endif

    /* stash away certain offsets for later use */
    mpid_offset = nlst[X_MPID].n_value;
    avenrun_offset = nlst[X_AVENRUN].n_value;
    total_offset = nlst[X_TOTAL].n_value;
    cp_time_offset = nlst[X_CP_TIME].n_value;

    /* this is used in calculating WCPU -- calculate it ahead of time */
    logcpu = log(loaddouble(ccpu));

    /* allocate space for pst structure array and array of pointers */
    bytes = nproc * sizeof(struct pst_status);
    pbase = (struct pst_status *)malloc(bytes);
    pref  = (struct pst_status **)malloc(nproc * sizeof(struct pst_status *));

    /* Just in case ... */
    if (pbase == (struct pst_status *)NULL || pref == (struct pst_status **)NULL)
    {
	fprintf(stderr, "top: can't allocate sufficient memory\n");
	return(-1);
    }

    /* get the page size with "getpagesize" and calculate pageshift from it */
    pagesize = getpagesize();
    pageshift = 0;
    while (pagesize > 1)
    {
	pageshift++;
	pagesize >>= 1;
    }

    /* we only need the amount of log(2)1024 for our conversion */
    pageshift -= LOG1024;

    /* fill in the statics information */
    statics->procstate_names = procstatenames;
    statics->cpustate_names = cpustatenames;
    statics->memory_names = memorynames;

    /* all done! */
    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;

{
    load_avg avenrun[3];
    long total;

    /* get the cp_time array */
    (void) getkval(cp_time_offset, (int *)cp_time, sizeof(cp_time),
		   "_cp_time");

    /* get load average array */
    (void) getkval(avenrun_offset, (int *)avenrun, sizeof(avenrun),
		   "_avenrun");

    /* get mpid -- process id of last process */
    (void) getkval(mpid_offset, &(si->last_pid), sizeof(si->last_pid),
		   "_mpid");

    /* convert load averages to doubles */
    {
	register int i;
	register double *infoloadp;
	register load_avg *sysloadp;

	infoloadp = si->load_avg;
	sysloadp = avenrun;
	for (i = 0; i < 3; i++)
	{
	    *infoloadp++ = loaddouble(*sysloadp++);
	}
    }

    /* convert cp_time counts to percentages */
    total = percentages(CPUSTATES, cpu_states, cp_time, cp_old, cp_diff);

    /* sum memory statistics */
    {
	struct vmtotal total;

	/* get total -- systemwide main memory usage structure */
	(void) getkval(total_offset, (int *)(&total), sizeof(total),
		       "_total");
	/* convert memory stats to Kbytes */
	memory_stats[0] = -1;
	memory_stats[1] = pagetok(total.t_arm);
	memory_stats[2] = pagetok(total.t_rm);
	memory_stats[3] = -1;
	memory_stats[4] = pagetok(total.t_avm);
	memory_stats[5] = pagetok(total.t_vm);
	memory_stats[6] = -1;
	memory_stats[7] = pagetok(total.t_free);
    }

    /* set arrays and strings */
    si->cpustates = cpu_states;
    si->memory = memory_stats;
}

static struct handle handle;

caddr_t get_process_info(si, sel, compare)

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

{
    register int i;
    register int total_procs;
    register int active_procs;
    register struct pst_status **prefp;
    register struct pst_status *pp;

    /* these are copied out of sel for speed */
    int show_idle;
    int show_system;
    int show_uid;
    int show_command;

    /* read all the pst structures in one fell swoop */
    if ((total_procs = pstat_getproc(pbase, sizeof(struct pst_status),
				     nproc, 0)) < 0)
    {
	perror("pstat_getproc");
	return(NULL);
    }

    /* 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 */
    active_procs = 0;
    memset((char *)process_states, 0, sizeof(process_states));
    prefp = pref;
    for (pp = pbase, i = 0; i < total_procs; pp++, i++)
    {
	/*
	 *  Place pointers to each valid pst structure in pref[].
	 *  Process slots that are actually in use have a non-zero
	 *  status field.  Processes with SSYS set are system
	 *  processes---these get ignored unless show_sysprocs is set.
	 */
	if (pp->pst_stat != 0 &&
	    (show_system || ((pp->pst_flag & PS_SYS) == 0)))
	{
	    process_states[pp->pst_stat]++;

	    /*
	     * idle processes can be selectively ignored:  a process is
	     * considered idle when cpticks is zero AND it is not in the run
	     * state.  Zombies are always ignored.  We also skip over 
	     * processes that have been excluded via a uid selection
	     */
	    if ((pp->pst_stat != PS_ZOMBIE) &&
		(show_idle || (pp->pst_cpticks != 0) || (pp->pst_stat == PS_RUN)) &&
		(!show_uid || pp->pst_uid == (uid_t)sel->uid))
	    {
		*prefp++ = pp;
		active_procs++;
	    }
	}
    }

    /* if requested, sort the "interesting" processes */
    if (compare != NULL)
    {
	qsort((char *)pref, active_procs, sizeof(struct pst_status *), 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 = pref;
    handle.remaining = active_procs;
    return((caddr_t)&handle);
}

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

char *format_next_process(handle, get_userid)

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

{
    register struct pst_status *pp;
    register long cputime;
    register double pct;
    int where;
    struct handle *hp;
    struct timeval time;
    struct timezone timezone;

    /* sanity check */
    if (handle == (caddr_t)NULL)
    {
	return("");
    }

    /* find and remember the next proc structure */
    hp = (struct handle *)handle;
    pp = *(hp->next_proc++);
    hp->remaining--;
    

    /* set ucomm for system processes */
    if (pp->pst_ucomm[0] == '\0')
    {
	/* is this ever going to happen? */
	if (pp->pst_pid == 0)
	{
	    (void) strcpy(pp->pst_ucomm, "Swapper");
	}
	else if (pp->pst_pid == 2)
	{
	    (void) strcpy(pp->pst_ucomm, "Pager");
	}
    }

    cputime = pp->pst_cptickstotal / hz;

    /* calculate the base for cpu percentages */
    pct = pctdouble(pp->pst_pctcpu);

    /* get time used for calculation in weighted_cpu */
    gettimeofday(&time, &timezone);

    /* format this entry */
    sprintf(fmt,
	    Proc_format,
	    pp->pst_pid,
	    (*get_userid)(pp->pst_uid),
	    pp->pst_pri,
	    pp->pst_nice,
	    format_k(pagetok(PROCSIZE(pp))),
	    format_k(pagetok(P_RSSIZE(pp))),
	    state_abbrev[pp->pst_stat],
	    format_time(cputime),
	    100.0 * weighted_cpu(pct, pp),
	    100.0 * pct,
	    printable(pp->pst_ucomm));

    /* return the result */
    return(fmt);
}

/*
 * check_nlist(nlst) - checks the nlist to see if any symbols were not
 *		found.  For every symbol that was not found, a one-line
 *		message is printed to stderr.  The routine returns the
 *		number of symbols NOT found.
 */

int check_nlist(nlst)

register struct nlist *nlst;

{
    register int i;

    /* check to see if we got ALL the symbols we requested */
    /* this will write one line to stderr for every symbol not found */

    i = 0;
    while (nlst->n_name != NULL)
    {
	if (nlst->n_type == 0)
	{
	    /* this one wasn't found */
	    fprintf(stderr, "kernel: no symbol named `%s'\n", nlst->n_name);
	    i = 1;
	}
	nlst++;
    }

    return(i);
}


/*
 *  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 (lseek(kmem, (long)offset, L_SET) == -1) {
        if (*refstr == '!')
            refstr++;
        (void) fprintf(stderr, "%s: lseek to %s: %s\n", KMEM, 
		       refstr, strerror(errno));
        quit(23);
    }
    if (read(kmem, (char *) ptr, size) == -1) {
        if (*refstr == '!') 
            return(0);
        else {
            (void) fprintf(stderr, "%s: reading %s: %s\n", KMEM, 
			   refstr, strerror(errno));
            quit(23);
        }
    }
    return(1);
}
    
/* 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		*/
    6,	/* run			*/
    4,	/* stop			*/
    2,	/* zombie		*/
    5,	/* start		*/
    1,  /* other                */
};
 
proc_compare(pp1, pp2)

struct pst_status **pp1;
struct pst_status **pp2;

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

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

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

    return(result);
}


void (*signal(sig, func))()
    int sig;
    void (*func)();
{
    struct sigvec osv, sv;

    /*
     * XXX: we should block the signal we are playing with,
     *	    in case we get interrupted in here.
     */
    if (sigvector(sig, NULL, &osv) == -1)
	return BADSIG;
    sv = osv;
    sv.sv_handler = func;
#ifdef SV_BSDSIG
    sv.sv_flags |= SV_BSDSIG;
#endif
    if (sigvector(sig, &sv, NULL) == -1)
	return BADSIG;
    return osv.sv_handler;
}

int getpagesize() { return 1 << PGSHIFT; }

int setpriority(a, b, c) { errno = ENOSYS; return -1; }

/*
 * 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 pst_status **prefp;
    register struct pst_status *pp;

    prefp = pref;
    cnt = pref_len;
    while (--cnt >= 0)
    {
	if ((pp = *prefp++)->pst_pid == (pid_t)pid)
	{
	    return((int)pp->pst_uid);
	}
    }
    return(-1);
}
