/*
 * pg_top - a top PostgreSQL users display for Unix
 *
 * SYNOPSIS:  PowerPC running AIX 4.2 or higher
 *
 * DESCRIPTION:
 * This is the machine-dependent module for AIX 4.2 and higher
 * It is currenlty only tested on PowerPC architectures.
 *
 * TERMCAP: -lcurses
 *
 * CFLAGS: -DORDER -DHAVE_GETOPT
 *
 * LIBS: -bD:0x18000000
 *
 * AUTHOR:	Joep Vesseur <joep@fwi.uva.nl>
 *
 * PATCHES: Antoine Tabary <tabary@bruyeres.cea.fr>
 */

#include "config.h"

#include <stdlib.h>
#include <stdio.h>
#include <fcntl.h>
#include <nlist.h>
#include <sys/sysinfo.h>
#include <procinfo.h>
#include <sys/proc.h>
#include <sys/times.h>
#include <sys/param.h>
#include <pwd.h>
#include "pg_top.h"
#include "machine.h"
#include "utils.h"


#define PROCRESS(p) (((p)->pi_trss + (p)->pi_drss)*4)
#define PROCSIZE(p) (((p)->pi_tsize/1024+(p)->pi_dvm)*4)
#define PROCTIME(pi) (pi->pi_ru.ru_utime.tv_sec + pi->pi_ru.ru_stime.tv_sec)


/*
 * structure definition taken from 'monitor' by Jussi Maki (jmaki@hut.fi)
 */
struct vmker
{
	uint		n0,
				n1,
				n2,
				n3,
				n4,
				n5,
				n6,
				n7,
				n8;
	uint		totalmem;
	uint		badmem;			/* this is used in RS/6000 model 220 */
	uint		freemem;
	uint		n12;
	uint		numperm;		/* this seems to keep other than text and data
								 * segment usage; name taken from
								 * /usr/lpp/bos/samples/vmtune.c */
	uint		totalvmem,
				freevmem;
	uint		n15,
				n16,
				n17,
				n18,
				n19;
};


#define KMEM "/dev/kmem"

/* Indices in the nlist array */
#define X_AVENRUN		0
#define X_SYSINFO		1
#define X_VMKER			2
#define X_PROC			3
#define X_V				4

static struct nlist nlst[] = {
	{"avenrun", 0, 0, 0, 0, 0}, /* 0 */
	{"sysinfo", 0, 0, 0, 0, 0}, /* 1 */
	{"vmker", 0, 0, 0, 0, 0},	/* 2 */
	{"proc", 0, 0, 0, 0, 0},	/* 3 */
	{"v", 0, 0, 0, 0, 0},		/* 4 */
	{NULL, 0, 0, 0, 0, 0}
};


/* get_process_info returns handle. definition is here */
struct handle
{
	struct procsinfo **next_proc;
	int			remaining;
};

/*
 *	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 7

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


/* these are for detailing the process states */
int			process_states[9];
char	   *procstatenames[] = {
	" none, ", " sleeping, ", " state2, ", " runnable, ",
	" idle, ", " zombie, ", " stopped, ", " running, ", " swapped, ",
	NULL
};


/* these are for detailing the cpu states */
int			cpu_states[4];
char	   *cpustatenames[] = {
	"idle", "user", "kernel", "wait",
	NULL
};

/* these are for detailing the memory statistics */
long		memory_stats[4];
char	   *memorynames[] = {
	"K Total, ", "K Free, ", "K Buffers", NULL
};

#define M_REAL	   0
#define M_REALFREE 1
#define M_BUFFERS  2

long		swap_stats[3];
char	   *swapnames[] = {
	"K Total, ", "K Free", NULL
};

#define M_VIRTUAL  0
#define M_VIRTFREE 1

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

/* sorting orders. first is default */
char	   *ordernames[] = {"cpu", "size", "res", "time", "pri", NULL};

/* compare routines */
int			compare_cpu(), compare_size(), compare_res(), compare_time(),
			compare_prio();

int			(*proc_compares[]) () =
{
	compare_cpu,
	compare_size,
	compare_res,
	compare_time,
	compare_prio,
	NULL
};

/* useful externals */
extern int	errno;
extern char *sys_errlist[];
long		lseek();
long		time();
long		percentages();


/* useful globals */
int			kmem;				/* file descriptor */

/* offsets in kernel */
static unsigned long avenrun_offset;
static unsigned long sysinfo_offset;
static unsigned long vmker_offset;
static unsigned long proc_offset;
static unsigned long v_offset;

/* used for calculating cpu state percentages */
static long cp_time[CPU_NTIMES];
static long cp_old[CPU_NTIMES];
static long cp_diff[CPU_NTIMES];

/* the runqueue length is a cumulative value. keep old value */
long		old_runque;

/* process info */
struct var	v_info;				/* to determine nprocs */
int			nprocs;				/* maximum nr of procs in proctab */
int			ncpus;				/* nr of cpus installed */

int			ptsize;				/* size of process table in bytes */
struct proc *p_proc;			/* a copy of the process table */
struct procsinfo *p_info;		/* needed for vm and ru info */
struct procsinfo **pref;		/* processes selected for display */
int			pref_len;			/* number of processes selected */

/* needed to calculate WCPU */
unsigned long curtime;


/*
 * Initialize globals, get kernel offsets and stuff...
 */
machine_init(struct statics * statics)

{
	time_t		uptime,
				now;
	struct tms	tbuf;

	if ((kmem = open(KMEM, O_RDONLY)) == -1)
	{
		perror(KMEM);
		return -1;
	}

	/* get kernel symbol offsets */
	if (knlist(nlst, 5, sizeof(struct nlist)) != 0)
	{
		perror("knlist");
		return -1;
	}
	avenrun_offset = nlst[X_AVENRUN].n_value;
	sysinfo_offset = nlst[X_SYSINFO].n_value;
	vmker_offset = nlst[X_VMKER].n_value;
	proc_offset = nlst[X_PROC].n_value;
	v_offset = nlst[X_V].n_value;

	getkval(v_offset, (caddr_t) & v_info, sizeof v_info, "v");

	ncpus = v_info.v_ncpus;		/* number of cpus */
	nprocs = PROCMASK(PIDMAX);
	if (nprocs > 1024)
		nprocs = 1024;

	ptsize = nprocs * sizeof(struct proc);
	p_proc = (struct proc *) malloc(ptsize);
	p_info = (struct procsinfo *) malloc(nprocs * sizeof(struct procsinfo));
	pref = (struct procsinfo **) malloc(nprocs * sizeof(struct procsinfo *));

	if (!p_proc || !p_info || !pref)
	{
		fprintf(stderr, "pg_top: not enough memory\n");
		return -1;
	}

	/* set boot time */
	now = time(NULL);
	uptime = times(&tbuf) / HZ;
	statics->boottime = now - uptime;

	statics->procstate_names = procstatenames;
	statics->cpustate_names = cpustatenames;
	statics->memory_names = memorynames;
	statics->order_names = ordernames;
	statics->swap_names = swapnames;

	return (0);
}



char *
format_header(char *uname_field)

{
	register char *ptr;

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

	return (header);
}



void
get_system_info(struct system_info * si)

{
	int			load_avg[3];
	struct sysinfo s_info;
	struct vmker m_info;
	int			i;
	double		total = 0;

	/* get the load avarage array */
	getkval(avenrun_offset, (caddr_t) load_avg, sizeof load_avg, "avenrun");

	/* get the sysinfo structure */
	getkval(sysinfo_offset, (caddr_t) & s_info, sizeof s_info, "sysinfo");

	/* get vmker structure */
	getkval(vmker_offset, (caddr_t) & m_info, sizeof m_info, "vmker");

	/* convert load avarages to doubles */
	for (i = 0; i < 3; i++)
		si->load_avg[i] = (double) load_avg[i] / 65536.0;

	/* calculate cpu state in percentages */
	for (i = 0; i < CPU_NTIMES; i++)
	{
		cp_old[i] = cp_time[i];
		cp_time[i] = s_info.cpu[i];
		cp_diff[i] = cp_time[i] - cp_old[i];
		total += cp_diff[i];
	}

	total = total / 1000.0;		/* pg_top itself will correct this */
	for (i = 0; i < CPU_NTIMES; i++)
	{
		cpu_states[i] = cp_diff[i] / total;
	}

	/* calculate memory statistics, scale 4K pages to megabytes */
#define PAGE_TO_MB(a) ((a)*4/1024)
	memory_stats[M_REAL] = PAGE_TO_MB(m_info.totalmem);
	memory_stats[M_REALFREE] = PAGE_TO_MB(m_info.freemem);
	memory_stats[M_BUFFERS] = PAGE_TO_MB(m_info.numperm);
	swap_stats[M_VIRTUAL] = PAGE_TO_MB(m_info.totalvmem);
	swap_stats[M_VIRTFREE] = PAGE_TO_MB(m_info.freevmem);

	/* runnable processes */
	process_states[0] = s_info.runque - old_runque;
	old_runque = s_info.runque;

	si->cpustates = cpu_states;
	si->memory = memory_stats;
	si->swap = swap_stats;
}

static struct handle handle;

caddr_t
get_process_info(struct system_info * si, struct process_select * sel, int compare_index)

{
	int			i,
				nproc;
	int			ptsize_util;
	int			active_procs = 0,
				total_procs = 0;
	struct procsinfo *pp,
			  **p_pref = pref;
	unsigned long pctcpu;
	pid_t		procsindex = 0;
	struct proc *p;

	si->procstates = process_states;

	curtime = time(0);

	/* get the procsinfo structures of all running processes */
	nproc = getprocs(p_info, sizeof(struct procsinfo), NULL, 0,
					 &procsindex, nprocs);
	if (nproc < 0)
	{
		perror("getprocs");
		quit(1);
	}

	/* the swapper has no cmd-line attached */
	strcpy(p_info[0].pi_comm, "swapper");

	/* get proc table */
	ptsize_util = (PROCMASK(p_info[nproc - 1].pi_pid) + 1) * sizeof(struct proc);
	getkval(proc_offset, (caddr_t) p_proc, ptsize_util, "proc");

	memset(process_states, 0, sizeof process_states);

	/*
	 * build a list of pointers to processes to show. walk through the list of
	 * procsinfo structures instead of the proc table since the mapping of
	 * procsinfo -> proctable is easy, the other way around is cumbersome
	 */
	for (pp = p_info, i = 0; i < nproc; pp++, i++)
	{

		p = &p_proc[PROCMASK(pp->pi_pid)];

		/*
		 * AIX marks all runnable processes as ACTIVE. We want to know which
		 * processes are sleeping, so check used cpu ticks and adjust status
		 * field accordingly
		 */
		if (p->p_stat == SACTIVE && p->p_cpticks == 0)
			p->p_stat = SIDL;

		if (pp->pi_state && (sel->system || ((pp->pi_flags & SKPROC) == 0)))
		{
			total_procs++;
			process_states[p->p_stat]++;
			if ((pp->pi_state != SZOMB) &&
				(sel->idle || p->p_cpticks != 0 || (p->p_stat == SACTIVE))
				&& (sel->uid == -1 || pp->pi_uid == (uid_t) sel->uid))
			{
				*p_pref++ = pp;
				active_procs++;
			}
		}
	}

	/*
	 * the pref array now holds pointers to the procsinfo structures in the
	 * p_info array that were selected for display
	 */

	/* sort if requested */
	if (si->p_active)
		qsort((char *) pref, active_procs, sizeof(struct procsinfo *),
			  proc_compares[compare_index]);

	si->last_pid = -1;			/* no way to figure out last used pid */
	si->p_total = total_procs;
	si->p_active = pref_len = active_procs;

	handle.next_proc = pref;
	handle.remaining = active_procs;

	return ((caddr_t) & handle);
}

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

/* define what weighted cpu is. use definition of %CPU from 'man ps(1)' */
#define weighted_cpu(pp) (PROCTIME(pp) == 0 ? 0.0 : \
						(((PROCTIME(pp)*100.0)/(curtime-pi->pi_start)/ncpus)))
#define double_pctcpu(p) ((double)p->p_pctcpu/(double)FLT_MODULO)

char *
format_next_process(caddr_t handle, char *(*get_userid) ())

{
	register struct handle *hp;
	register struct procsinfo *pi;
	register struct proc *p;
	char	   *uname;
	long		cpu_time;
	int			proc_size,
				proc_ress;
	char		size_unit = 'K';
	char		ress_unit = 'K';

	hp = (struct handle *) handle;
	if (hp->remaining == 0)
	{							/* safe guard */
		fmt[0] = '\0';
		return fmt;
	}
	pi = *(hp->next_proc++);
	hp->remaining--;
	p = &p_proc[PROCMASK(pi->pi_pid)];

	cpu_time = PROCTIME(pi);

	/* we disply sizes up to 10M in KiloBytes, beyond 10M in MegaBytes */
	if ((proc_size = (pi->pi_tsize / 1024 + pi->pi_dvm) * 4) > 10240)
	{
		proc_size /= 1024;
		size_unit = 'M';
	}
	if ((proc_ress = (pi->pi_trss + pi->pi_drss) * 4) > 10240)
	{
		proc_ress /= 1024;
		ress_unit = 'M';
	}

	sprintf(fmt, Proc_format,
			pi->pi_pid,			/* PID */
			(*get_userid) (pi->pi_uid), /* login name */
			getpriority(PRIO_PROCESS, pi->pi_pid),
			EXTRACT_NICE(p),	/* fixed or vari */
			proc_size,			/* size */
			size_unit,			/* K or M */
			proc_ress,			/* resident */
			ress_unit,			/* K or M */
			state_abbrev[p->p_stat],	/* process state */
			format_time(cpu_time),		/* time used */
			weighted_cpu(pi),	/* WCPU */
			100.0 * double_pctcpu(p),	/* CPU */
			printable(pi->pi_comm),		/* COMM */
			(pi->pi_flags & SKPROC) == 0 ? "" : " (sys)"		/* kernel process? */
		);
	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).
 *
 */

int
getkval(unsigned long offset, caddr_t ptr, int size, char *refstr)

{
	int			upper_2gb = 0;

	/*
	 * reads above 2Gb are done by seeking to offset%2Gb, and supplying 1
	 * (opposed to 0) as fourth parameter to readx (see 'man kmem')
	 */
	if (offset > 1 << 31)
	{
		upper_2gb = 1;
		offset &= 0x7fffffff;
	}

	if (lseek(kmem, offset, SEEK_SET) != offset)
	{
		fprintf(stderr, "pg_top: lseek failed\n");
		quit(2);
	}

	if (readx(kmem, ptr, size, upper_2gb) != size)
	{
		if (*refstr == '!')
			return 0;
		else
		{
			fprintf(stderr, "pg_top: kvm_read for %s: %s\n", refstr,
					sys_errlist[errno]);
			quit(2);
		}
	}

	return 1;
}

/* comparison routine for qsort */
/*
 * The following code is taken from the solaris module and adjusted
 * for AIX -- JV .
 */

#define ORDERKEY_PCTCPU \
		   if (lresult = p2->p_pctcpu - p1->p_pctcpu, \
			   (result = lresult > 0 ? 1 : lresult < 0 ? -1 : 0) == 0)

#define ORDERKEY_CPTICKS \
		   if ((result = PROCTIME(pi2) - PROCTIME(pi1)) == 0)


#define ORDERKEY_STATE \
		   if ((result = sorted_state[p2->p_stat]  \
						 - sorted_state[p1->p_stat])  == 0)

/* Nice values directly reflect the process' priority, and are always >0 ;-) */
#define ORDERKEY_PRIO \
	   if ((result = EXTRACT_NICE(p1) - EXTRACT_NICE(p2)) == 0)

#define ORDERKEY_RSSIZE \
		   if ((result = PROCRESS(pi2) - PROCRESS(pi1)) == 0)
#define ORDERKEY_MEM \
		   if ((result = PROCSIZE(pi2) - PROCSIZE(pi1)) == 0)

static unsigned char sorted_state[] =
{
	0,							/* not used */
	0,
	0,
	0,
	3,							/* sleep */
	1,							/* zombie */
	4,							/* stop */
	6,							/* run */
	2,							/* swap */
};

/* compare_cpu - the comparison function for sorting by cpu percentage */

int
compare_cpu(struct procsinfo ** ppi1, struct procsinfo ** ppi2)

{
	register struct procsinfo *pi1 = *ppi1,
			   *pi2 = *ppi2;
	register struct proc *p1;
	register struct proc *p2;
	register int result;
	register long lresult;

	p1 = &p_proc[PROCMASK(pi1->pi_pid)];
	p2 = &p_proc[PROCMASK(pi2->pi_pid)];

	ORDERKEY_PCTCPU
		ORDERKEY_CPTICKS
		ORDERKEY_STATE
		ORDERKEY_PRIO
		ORDERKEY_RSSIZE
		ORDERKEY_MEM
		;

	return result;
}


/* compare_size - the comparison function for sorting by total memory usage */

int
compare_size(struct procsinfo ** ppi1, struct procsinfo ** ppi2)

{
	register struct procsinfo *pi1 = *ppi1,
			   *pi2 = *ppi2;
	register struct proc *p1;
	register struct proc *p2;
	register int result;
	register long lresult;

	p1 = &p_proc[PROCMASK(pi1->pi_pid)];
	p2 = &p_proc[PROCMASK(pi2->pi_pid)];

	ORDERKEY_MEM
		ORDERKEY_RSSIZE
		ORDERKEY_PCTCPU
		ORDERKEY_CPTICKS
		ORDERKEY_STATE
		ORDERKEY_PRIO
		;

	return result;
}


/* compare_res - the comparison function for sorting by resident set size */

int
compare_res(struct procsinfo ** ppi1, struct procsinfo ** ppi2)

{
	register struct procsinfo *pi1 = *ppi1,
			   *pi2 = *ppi2;
	register struct proc *p1;
	register struct proc *p2;
	register int result;
	register long lresult;

	p1 = &p_proc[PROCMASK(pi1->pi_pid)];
	p2 = &p_proc[PROCMASK(pi2->pi_pid)];

	ORDERKEY_RSSIZE
		ORDERKEY_MEM
		ORDERKEY_PCTCPU
		ORDERKEY_CPTICKS
		ORDERKEY_STATE
		ORDERKEY_PRIO
		;

	return result;
}


/* compare_time - the comparison function for sorting by total cpu time */

int
compare_time(struct procsinfo ** ppi1, struct procsinfo ** ppi2)

{
	register struct procsinfo *pi1 = *ppi1,
			   *pi2 = *ppi2;
	register struct proc *p1;
	register struct proc *p2;
	register int result;
	register long lresult;

	p1 = &p_proc[PROCMASK(pi1->pi_pid)];
	p2 = &p_proc[PROCMASK(pi2->pi_pid)];

	ORDERKEY_CPTICKS
		ORDERKEY_PCTCPU
		ORDERKEY_STATE
		ORDERKEY_PRIO
		ORDERKEY_MEM
		ORDERKEY_RSSIZE
		;

	return result;
}


/* compare_prio - the comparison function for sorting by cpu percentage */

int
compare_prio(struct procsinfo ** ppi1, struct procsinfo ** ppi2)

{
	register struct procsinfo *pi1 = *ppi1,
			   *pi2 = *ppi2;
	register struct proc *p1;
	register struct proc *p2;
	register int result;
	register long lresult;

	p1 = &p_proc[PROCMASK(pi1->pi_pid)];
	p2 = &p_proc[PROCMASK(pi2->pi_pid)];

	ORDERKEY_PRIO
		ORDERKEY_PCTCPU
		ORDERKEY_CPTICKS
		ORDERKEY_STATE
		ORDERKEY_RSSIZE
		ORDERKEY_MEM
		;

	return result;
}

int
proc_owner(int pid)

{
	int			uid;
	register struct procsinfo **prefp = pref;
	register int cnt = pref_len;

	while (--cnt >= 0)
	{
		if ((*prefp)->pi_pid == pid)
			return (*prefp)->pi_uid;
		prefp++;
	}

	return (-1);
}