/*-
 * SPDX-License-Identifier: BSD-4-Clause
 *
 * Copyright (c) 1994 Christopher G. Demetriou
 * All rights reserved.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions
 * are met:
 * 1. Redistributions of source code must retain the above copyright
 *    notice, this list of conditions and the following disclaimer.
 * 2. Redistributions in binary form must reproduce the above copyright
 *    notice, this list of conditions and the following disclaimer in the
 *    documentation and/or other materials provided with the distribution.
 * 3. All advertising materials mentioning features or use of this software
 *    must display the following acknowledgement:
 *      This product includes software developed by Christopher G. Demetriou.
 * 4. The name of the author may not be used to endorse or promote products
 *    derived from this software without specific prior written permission
 *
 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
 * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
 * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
 * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
 * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
 * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
 * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
 */

/*
 * sa:  system accounting
 */

#include <sys/types.h>
#include <sys/acct.h>
#include <ctype.h>
#include <err.h>
#include <errno.h>
#include <fcntl.h>
#include <signal.h>
#include <stdint.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <unistd.h>
#include "extern.h"
#include "pathnames.h"

static FILE     *acct_load(const char *, int);
static int       cmp_comm(const char *, const char *);
static int       cmp_usrsys(const DBT *, const DBT *);
static int       cmp_avgusrsys(const DBT *, const DBT *);
static int       cmp_dkio(const DBT *, const DBT *);
static int       cmp_avgdkio(const DBT *, const DBT *);
static int       cmp_cpumem(const DBT *, const DBT *);
static int       cmp_avgcpumem(const DBT *, const DBT *);
static int       cmp_calls(const DBT *, const DBT *);
static void      usage(void);

int aflag, bflag, cflag, dflag, Dflag, fflag, iflag, jflag, kflag;
int Kflag, lflag, mflag, qflag, rflag, sflag, tflag, uflag, vflag;
u_quad_t cutoff = 1;
const char *pdb_file = _PATH_SAVACCT;
const char *usrdb_file = _PATH_USRACCT;

static char     *dfltargv[] = { NULL };
static int      dfltargc = (sizeof dfltargv/sizeof(char *));

/* default to comparing by sum of user + system time */
cmpf_t   sa_cmp = cmp_usrsys;

int
main(int argc, char **argv)
{
        FILE *f;
        char pathacct[] = _PATH_ACCT;
        int ch, error = 0;

        dfltargv[0] = pathacct;

        while ((ch = getopt(argc, argv, "abcdDfijkKlmnP:qrstuU:v:")) != -1)
                switch (ch) {
                        case 'a':
                                /* print all commands */
                                aflag = 1;
                                break;
                        case 'b':
                                /* sort by per-call user/system time average */
                                bflag = 1;
                                sa_cmp = cmp_avgusrsys;
                                break;
                        case 'c':
                                /* print percentage total time */
                                cflag = 1;
                                break;
                        case 'd':
                                /* sort by averge number of disk I/O ops */
                                dflag = 1;
                                sa_cmp = cmp_avgdkio;
                                break;
                        case 'D':
                                /* print and sort by total disk I/O ops */
                                Dflag = 1;
                                sa_cmp = cmp_dkio;
                                break;
                        case 'f':
                                /* force no interactive threshold comprison */
                                fflag = 1;
                                break;
                        case 'i':
                                /* do not read in summary file */
                                iflag = 1;
                                break;
                        case 'j':
                                /* instead of total minutes, give sec/call */
                                jflag = 1;
                                break;
                        case 'k':
                                /* sort by cpu-time average memory usage */
                                kflag = 1;
                                sa_cmp = cmp_avgcpumem;
                                break;
                        case 'K':
                                /* print and sort by cpu-storage integral */
                                sa_cmp = cmp_cpumem;
                                Kflag = 1;
                                break;
                        case 'l':
                                /* separate system and user time */
                                lflag = 1;
                                break;
                        case 'm':
                                /* print procs and time per-user */
                                mflag = 1;
                                break;
                        case 'n':
                                /* sort by number of calls */
                                sa_cmp = cmp_calls;
                                break;
                        case 'P':
                                /* specify program database summary file */
                                pdb_file = optarg;
                                break;
                        case 'q':
                                /* quiet; error messages only */
                                qflag = 1;
                                break;
                        case 'r':
                                /* reverse order of sort */
                                rflag = 1;
                                break;
                        case 's':
                                /* merge accounting file into summaries */
                                sflag = 1;
                                break;
                        case 't':
                                /* report ratio of user and system times */
                                tflag = 1;
                                break;
                        case 'u':
                                /* first, print uid and command name */
                                uflag = 1;
                                break;
                        case 'U':
                                /* specify user database summary file */
                                usrdb_file = optarg;
                                break;
                        case 'v':
                                /* cull junk */
                                vflag = 1;
                                cutoff = atoi(optarg);
                                break;
                        case '?':
                        default:
                                usage();
                }

        argc -= optind;
        argv += optind;

        /* various argument checking */
        if (fflag && !vflag)
                errx(1, "only one of -f requires -v");
        if (fflag && aflag)
                errx(1, "only one of -a and -v may be specified");
        /* XXX need more argument checking */

        if (!uflag) {
                /* initialize tables */
                if ((sflag || (!mflag && !qflag)) && pacct_init() != 0)
                        errx(1, "process accounting initialization failed");
                if ((sflag || (mflag && !qflag)) && usracct_init() != 0)
                        errx(1, "user accounting initialization failed");
        }

        if (argc == 0) {
                argc = dfltargc;
                argv = dfltargv;
        }

        /* for each file specified */
        for (; argc > 0; argc--, argv++) {
                /*
                 * load the accounting data from the file.
                 * if it fails, go on to the next file.
                 */
                f = acct_load(argv[0], sflag);
                if (f == NULL)
                        continue;

                if (!uflag && sflag) {
#ifndef DEBUG
                        sigset_t nmask, omask;
                        int unmask = 1;

                        /*
                         * block most signals so we aren't interrupted during
                         * the update.
                         */
                        if (sigfillset(&nmask) == -1) {
                                warn("sigfillset");
                                unmask = 0;
                                error = 1;
                        }
                        if (unmask &&
                            (sigprocmask(SIG_BLOCK, &nmask, &omask) == -1)) {
                                warn("couldn't set signal mask");
                                unmask = 0;
                                error = 1;
                        }
#endif /* DEBUG */

                        /*
                         * truncate the accounting data file ASAP, to avoid
                         * losing data.  don't worry about errors in updating
                         * the saved stats; better to underbill than overbill,
                         * but we want every accounting record intact.
                         */
                        if (ftruncate(fileno(f), 0) == -1) {
                                warn("couldn't truncate %s", *argv);
                                error = 1;
                        }

                        /*
                         * update saved user and process accounting data.
                         * note errors for later.
                         */
                        if (pacct_update() != 0 || usracct_update() != 0)
                                error = 1;

#ifndef DEBUG
                        /*
                         * restore signals
                         */
                        if (unmask &&
                            (sigprocmask(SIG_SETMASK, &omask, NULL) == -1)) {
                                warn("couldn't restore signal mask");
                                error = 1;
                        }
#endif /* DEBUG */
                }

                /*
                 * close the opened accounting file
                 */
                if (fclose(f) == EOF) {
                        warn("fclose %s", *argv);
                        error = 1;
                }
        }

        if (!uflag && !qflag) {
                /* print any results we may have obtained. */
                if (!mflag)
                        pacct_print();
                else
                        usracct_print();
        }

        if (!uflag) {
                /* finally, deallocate databases */
                if (sflag || (!mflag && !qflag))
                        pacct_destroy();
                if (sflag || (mflag && !qflag))
                        usracct_destroy();
        }

        exit(error);
}

static void
usage(void)
{
        (void)fprintf(stderr,
                "usage: sa [-abcdDfijkKlmnqrstu] [-P file] [-U file] [-v cutoff] [file ...]\n");
        exit(1);
}

static FILE *
acct_load(const char *pn, int wr)
{
        struct acctv3 ac;
        struct cmdinfo ci;
        ssize_t rv;
        FILE *f;
        int i;

        /*
         * open the file
         */
        f = fopen(pn, wr ? "r+" : "r");
        if (f == NULL) {
                warn("open %s %s", pn, wr ? "for read/write" : "read-only");
                return (NULL);
        }

        /*
         * read all we can; don't stat and open because more processes
         * could exit, and we'd miss them
         */
        while (1) {
                /* get one accounting entry and punt if there's an error */
                rv = readrec_forward(f, &ac);
                if (rv != 1) {
                        if (rv == EOF)
                                warn("error reading %s", pn);
                        break;
                }

                /* decode it */
                ci.ci_calls = 1;
                for (i = 0; i < (int)sizeof ac.ac_comm && ac.ac_comm[i] != '\0';
                    i++) {
                        char c = ac.ac_comm[i];

                        if (!isascii(c) || iscntrl(c)) {
                                ci.ci_comm[i] = '?';
                                ci.ci_flags |= CI_UNPRINTABLE;
                        } else
                                ci.ci_comm[i] = c;
                }
                if (ac.ac_flagx & AFORK)
                        ci.ci_comm[i++] = '*';
                ci.ci_comm[i++] = '\0';
                ci.ci_etime = ac.ac_etime;
                ci.ci_utime = ac.ac_utime;
                ci.ci_stime = ac.ac_stime;
                ci.ci_uid = ac.ac_uid;
                ci.ci_mem = ac.ac_mem;
                ci.ci_io = ac.ac_io;

                if (!uflag) {
                        /* and enter it into the usracct and pacct databases */
                        if (sflag || (!mflag && !qflag))
                                pacct_add(&ci);
                        if (sflag || (mflag && !qflag))
                                usracct_add(&ci);
                } else if (!qflag)
                        printf("%6u %12.3lf cpu %12.0lfk mem %12.0lf io %s\n",
                            ci.ci_uid,
                            (ci.ci_utime + ci.ci_stime) / 1000000,
                            ci.ci_mem, ci.ci_io,
                            ci.ci_comm);
        }

        /* Finally, return the file stream for possible truncation. */
        return (f);
}

/* sort commands, doing the right thing in terms of reversals */
static int
cmp_comm(const char *s1, const char *s2)
{
        int rv;

        rv = strcmp(s1, s2);
        if (rv == 0)
                rv = -1;
        return (rflag ? rv : -rv);
}

/* sort by total user and system time */
static int
cmp_usrsys(const DBT *d1, const DBT *d2)
{
        struct cmdinfo c1, c2;
        double t1, t2;

        memcpy(&c1, d1->data, sizeof(c1));
        memcpy(&c2, d2->data, sizeof(c2));

        t1 = c1.ci_utime + c1.ci_stime;
        t2 = c2.ci_utime + c2.ci_stime;

        if (t1 < t2)
                return -1;
        else if (t1 == t2)
                return (cmp_comm(c1.ci_comm, c2.ci_comm));
        else
                return 1;
}

/* sort by average user and system time */
static int
cmp_avgusrsys(const DBT *d1, const DBT *d2)
{
        struct cmdinfo c1, c2;
        double t1, t2;

        memcpy(&c1, d1->data, sizeof(c1));
        memcpy(&c2, d2->data, sizeof(c2));

        t1 = c1.ci_utime + c1.ci_stime;
        t1 /= (double) (c1.ci_calls ? c1.ci_calls : 1);

        t2 = c2.ci_utime + c2.ci_stime;
        t2 /= (double) (c2.ci_calls ? c2.ci_calls : 1);

        if (t1 < t2)
                return -1;
        else if (t1 == t2)
                return (cmp_comm(c1.ci_comm, c2.ci_comm));
        else
                return 1;
}

/* sort by total number of disk I/O operations */
static int
cmp_dkio(const DBT *d1, const DBT *d2)
{
        struct cmdinfo c1, c2;

        memcpy(&c1, d1->data, sizeof(c1));
        memcpy(&c2, d2->data, sizeof(c2));

        if (c1.ci_io < c2.ci_io)
                return -1;
        else if (c1.ci_io == c2.ci_io)
                return (cmp_comm(c1.ci_comm, c2.ci_comm));
        else
                return 1;
}

/* sort by average number of disk I/O operations */
static int
cmp_avgdkio(const DBT *d1, const DBT *d2)
{
        struct cmdinfo c1, c2;
        double n1, n2;

        memcpy(&c1, d1->data, sizeof(c1));
        memcpy(&c2, d2->data, sizeof(c2));

        n1 = c1.ci_io / (double) (c1.ci_calls ? c1.ci_calls : 1);
        n2 = c2.ci_io / (double) (c2.ci_calls ? c2.ci_calls : 1);

        if (n1 < n2)
                return -1;
        else if (n1 == n2)
                return (cmp_comm(c1.ci_comm, c2.ci_comm));
        else
                return 1;
}

/* sort by the cpu-storage integral */
static int
cmp_cpumem(const DBT *d1, const DBT *d2)
{
        struct cmdinfo c1, c2;

        memcpy(&c1, d1->data, sizeof(c1));
        memcpy(&c2, d2->data, sizeof(c2));

        if (c1.ci_mem < c2.ci_mem)
                return -1;
        else if (c1.ci_mem == c2.ci_mem)
                return (cmp_comm(c1.ci_comm, c2.ci_comm));
        else
                return 1;
}

/* sort by the cpu-time average memory usage */
static int
cmp_avgcpumem(const DBT *d1, const DBT *d2)
{
        struct cmdinfo c1, c2;
        double t1, t2;
        double n1, n2;

        memcpy(&c1, d1->data, sizeof(c1));
        memcpy(&c2, d2->data, sizeof(c2));

        t1 = c1.ci_utime + c1.ci_stime;
        t2 = c2.ci_utime + c2.ci_stime;

        n1 = c1.ci_mem / (t1 ? t1 : 1);
        n2 = c2.ci_mem / (t2 ? t2 : 1);

        if (n1 < n2)
                return -1;
        else if (n1 == n2)
                return (cmp_comm(c1.ci_comm, c2.ci_comm));
        else
                return 1;
}

/* sort by the number of invocations */
static int
cmp_calls(const DBT *d1, const DBT *d2)
{
        struct cmdinfo c1, c2;

        memcpy(&c1, d1->data, sizeof(c1));
        memcpy(&c2, d2->data, sizeof(c2));

        if (c1.ci_calls < c2.ci_calls)
                return -1;
        else if (c1.ci_calls == c2.ci_calls)
                return (cmp_comm(c1.ci_comm, c2.ci_comm));
        else
                return 1;
}