cmd/truss/actions.c

/*
 * CDDL HEADER START
 *
 * The contents of this file are subject to the terms of the
 * Common Development and Distribution License (the "License").
 * You may not use this file except in compliance with the License.
 *
 * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE
 * or http://www.opensolaris.org/os/licensing.
 * See the License for the specific language governing permissions
 * and limitations under the License.
 *
 * When distributing Covered Code, include this CDDL HEADER in each
 * file and include the License file at usr/src/OPENSOLARIS.LICENSE.
 * If applicable, add the following below this CDDL HEADER, with the
 * fields enclosed by brackets "[]" replaced with your own identifying
 * information: Portions Copyright [yyyy] [name of copyright owner]
 *
 * CDDL HEADER END
 */

/*
 * Copyright (c) 1989, 2010, Oracle and/or its affiliates. All rights reserved.
 */

/*  Copyright (c) 1988 AT&T */
/*    All Rights Reserved   */

#include <stdio.h>
#include <stdlib.h>
#include <unistd.h>
#include <ctype.h>
#include <string.h>
#include <memory.h>
#include <errno.h>
#include <limits.h>
#include <sys/types.h>
#include <sys/stack.h>
#include <signal.h>
#include <sys/isa_defs.h>
#include <libproc.h>
#include <priv.h>
#include "ramdata.h"
#include "systable.h"
#include "print.h"
#include "proto.h"

/*
 * Actions to take when process stops.
 */

/*
 * Function prototypes for static routines in this module.
 */
int stopsig(private_t *);
void    showpaths(private_t *, const struct systable *);
void    showargs(private_t *, int);
void    dumpargs(private_t *, long, const char *);

/*
 * Report an lwp to be sleeping (if true).
 */
void
report_sleeping(private_t *pri, int dotrace)
{
    const lwpstatus_t *Lsp = pri->lwpstat;
    int sys = Lsp->pr_syscall;

    if (!prismember(&trace, sys) || !dotrace ||
        !(Lsp->pr_flags & (PR_ASLEEP|PR_VFORKP))) {
        /* Make sure we catch sysexit even if we're not tracing it. */
        (void) Psysexit(Proc, sys, TRUE);
        return;
    }

    pri->length = 0;
    pri->Errno = 0;
    pri->ErrPriv = PRIV_NONE;
    pri->Rval1 = pri->Rval2 = 0;
    (void) sysentry(pri, dotrace);
    make_pname(pri, 0);
    putpname(pri);
    timestamp(pri);
    pri->length += printf("%s", pri->sys_string);
    pri->sys_leng = 0;
    *pri->sys_string = '\0';
    pri->length >>= 3;
    if (Lsp->pr_flags & PR_VFORKP)
        pri->length += 2;
    if (pri->length >= 4)
        (void) fputc(' ', stdout);
    for (; pri->length < 4; pri->length++)
        (void) fputc('\t', stdout);
    if (Lsp->pr_flags & PR_VFORKP)
        (void) fputs("(waiting for child to exit()/exec()...)\n",
            stdout);
    else
        (void) fputs("(sleeping...)\n", stdout);
    pri->length = 0;
    if (prismember(&verbose, sys)) {
        int raw = prismember(&rawout, sys);
        pri->Errno = 1;
        expound(pri, 0, raw);
        pri->Errno = 0;
    }
    Flush();
}

/*
 * requested() gets called for these reasons:
 *  flag == JOBSIG:     report nothing; change state to JOBSTOP
 *  flag == JOBSTOP:    report "Continued ..."
 *  default:        report sleeping system call
 *
 * It returns a new flag:  JOBSTOP or SLEEPING or 0.
 */
int
requested(private_t *pri, int flag, int dotrace)
{
    const lwpstatus_t *Lsp = pri->lwpstat;
    int sig = Lsp->pr_cursig;
    int newflag = 0;

    switch (flag) {
    case JOBSIG:
        return (JOBSTOP);

    case JOBSTOP:
        if (dotrace && !cflag && prismember(&signals, sig)) {
            pri->length = 0;
            putpname(pri);
            timestamp(pri);
            (void) printf("    Continued with signal #%d, %s",
                sig, signame(pri, sig));
            if (Lsp->pr_action.sa_handler == SIG_DFL)
                (void) printf(" [default]");
            else if (Lsp->pr_action.sa_handler == SIG_IGN)
                (void) printf(" [ignored]");
            else
                (void) printf(" [caught]");
            (void) fputc('\n', stdout);
            Flush();
        }
        newflag = 0;
        break;

    default:
        newflag = SLEEPING;
        if (!cflag)
            report_sleeping(pri, dotrace);
        break;
    }

    return (newflag);
}

int
jobcontrol(private_t *pri, int dotrace)
{
    const lwpstatus_t *Lsp = pri->lwpstat;
    int sig = stopsig(pri);

    if (sig == 0)
        return (0);

    if (dotrace && !cflag &&        /* not just counting */
        prismember(&signals, sig)) {    /* tracing this signal */
        int sys;

        pri->length = 0;
        putpname(pri);
        timestamp(pri);
        (void) printf("    Stopped by signal #%d, %s",
            sig, signame(pri, sig));
        if ((Lsp->pr_flags & PR_ASLEEP) &&
            (sys = Lsp->pr_syscall) > 0 && sys <= PRMAXSYS)
            (void) printf(", in %s()",
                sysname(pri, sys, getsubcode(pri)));
        (void) fputc('\n', stdout);
        Flush();
    }

    return (JOBSTOP);
}

/*
 * Return the signal the process stopped on iff process is already stopped on
 * PR_JOBCONTROL or is stopped on PR_SIGNALLED or PR_REQUESTED with a current
 * signal that will cause a JOBCONTROL stop when the process is set running.
 */
int
stopsig(private_t *pri)
{
    const lwpstatus_t *Lsp = pri->lwpstat;
    int sig = 0;

    if (Lsp->pr_flags & PR_STOPPED) {
        switch (Lsp->pr_why) {
        case PR_JOBCONTROL:
            sig = Lsp->pr_what;
            if (sig < 0 || sig > PRMAXSIG)
                sig = 0;
            break;
        case PR_SIGNALLED:
        case PR_REQUESTED:
            if (Lsp->pr_action.sa_handler == SIG_DFL) {
                switch (Lsp->pr_cursig) {
                case SIGSTOP:
                    sig = SIGSTOP;
                    break;
                case SIGTSTP:
                case SIGTTIN:
                case SIGTTOU:
                    if (!(Lsp->pr_flags & PR_ORPHAN))
                        sig = Lsp->pr_cursig;
                    break;
                }
            }
            break;
        }
    }

    return (sig);
}

int
signalled(private_t *pri, int flag, int dotrace)
{
    const lwpstatus_t *Lsp = pri->lwpstat;
    int sig = Lsp->pr_what;

    if (sig <= 0 || sig > PRMAXSIG) /* check bounds */
        return (0);

    if (dotrace && cflag) {         /* just counting */
        (void) mutex_lock(&count_lock);
        Cp->sigcount[sig]++;
        (void) mutex_unlock(&count_lock);
    }

    if (sig == SIGCONT && (flag == JOBSIG || flag == JOBSTOP))
        flag = requested(pri, JOBSTOP, dotrace);
    else if ((flag = jobcontrol(pri, dotrace)) == 0 &&
        !cflag && dotrace &&
        prismember(&signals, sig)) {
        int sys;

        pri->length = 0;
        putpname(pri);
        timestamp(pri);
        (void) printf("    Received signal #%d, %s",
            sig, signame(pri, sig));
        if ((Lsp->pr_flags & PR_ASLEEP) &&
            (sys = Lsp->pr_syscall) > 0 && sys <= PRMAXSYS)
            (void) printf(", in %s()",
                sysname(pri, sys, getsubcode(pri)));
        if (Lsp->pr_action.sa_handler == SIG_DFL)
            (void) printf(" [default]");
        else if (Lsp->pr_action.sa_handler == SIG_IGN)
            (void) printf(" [ignored]");
        else
            (void) printf(" [caught]");
        (void) fputc('\n', stdout);
        if (Lsp->pr_info.si_code != 0 ||
            Lsp->pr_info.si_pid != 0)
            print_siginfo(pri, &Lsp->pr_info);
        Flush();
    }

    if (flag == JOBSTOP)
        flag = JOBSIG;
    return (flag);
}

int
faulted(private_t *pri, int dotrace)
{
    const lwpstatus_t *Lsp = pri->lwpstat;
    int flt = Lsp->pr_what;

    if ((uint_t)flt > PRMAXFAULT || !prismember(&faults, flt) || !dotrace)
        return (0);

    (void) mutex_lock(&count_lock);
    Cp->fltcount[flt]++;
    (void) mutex_unlock(&count_lock);

    if (cflag)      /* just counting */
        return (1);

    pri->length = 0;
    putpname(pri);
    timestamp(pri);

    (void) printf("    Incurred fault #%d, %s  %%pc = 0x%.8lX",
        flt, proc_fltname(flt, pri->flt_name, sizeof (pri->flt_name)),
        (long)Lsp->pr_reg[R_PC]);

    if (flt == FLTPAGE)
        (void) printf("  addr = 0x%.8lX",
            (long)Lsp->pr_info.si_addr);
    (void) fputc('\n', stdout);
    if (Lsp->pr_info.si_signo != 0)
        print_siginfo(pri, &Lsp->pr_info);
    Flush();
    return (1);
}

/*
 * Set up pri->sys_nargs and pri->sys_args[] (syscall args).
 */
void
setupsysargs(private_t *pri, int what)
{
    const lwpstatus_t *Lsp = pri->lwpstat;
    int nargs;
    int i;

#if sparc
    /* determine whether syscall is indirect */
    pri->sys_indirect = (Lsp->pr_reg[R_G1] == SYS_syscall)? 1 : 0;
#else
    pri->sys_indirect = 0;
#endif

    (void) memset(pri->sys_args, 0, sizeof (pri->sys_args));
    if (what != Lsp->pr_syscall) {  /* assertion */
        (void) printf("%s\t*** Inconsistent syscall: %d vs %d ***\n",
            pri->pname, what, Lsp->pr_syscall);
    }
    nargs = Lsp->pr_nsysarg;
    for (i = 0;
        i < nargs && i < sizeof (pri->sys_args) / sizeof (pri->sys_args[0]);
        i++)
        pri->sys_args[i] = Lsp->pr_sysarg[i];
    pri->sys_nargs = nargs;
}

#define ISREAD(code) \
    ((code) == SYS_read || (code) == SYS_pread || \
    (code) == SYS_pread64 || (code) == SYS_readv || \
    (code) == SYS_recv || (code) == SYS_recvfrom)
#define ISWRITE(code) \
    ((code) == SYS_write || (code) == SYS_pwrite || \
    (code) == SYS_pwrite64 || (code) == SYS_writev || \
    (code) == SYS_send || (code) == SYS_sendto)

/*
 * Return TRUE iff syscall is being traced.
 */
int
sysentry(private_t *pri, int dotrace)
{
    pid_t pid = Pstatus(Proc)->pr_pid;
    const lwpstatus_t *Lsp = pri->lwpstat;
    long arg;
    int nargs;
    int i;
    int x;
    int len;
    char *s;
    const struct systable *stp;
    int what = Lsp->pr_what;
    int subcode;
    int istraced;
    int raw;

    /* for reporting sleeping system calls */
    if (what == 0 && (Lsp->pr_flags & (PR_ASLEEP|PR_VFORKP)))
        what = Lsp->pr_syscall;

    /* protect ourself from operating system error */
    if (what <= 0 || what > PRMAXSYS)
        what = 0;

    /*
     * Set up the system call arguments (pri->sys_nargs & pri->sys_args[]).
     */
    setupsysargs(pri, what);
    nargs = pri->sys_nargs;

    /* get systable entry for this syscall */
    subcode = getsubcode(pri);
    stp = subsys(what, subcode);

    if (nargs > stp->nargs)
        nargs = stp->nargs;
    pri->sys_nargs = nargs;

    /*
     * Fetch and remember first argument if it's a string,
     * or second argument if SYS_openat or SYS_openat64.
     */
    pri->sys_valid = FALSE;
    if ((nargs > 0 && stp->arg[0] == STG) ||
        (nargs > 1 && (what == SYS_openat || what == SYS_openat64))) {
        long offset;
        uint32_t offset32;

        /*
         * Special case for exit from exec().
         * The address in pri->sys_args[0] refers to the old process
         * image.  We must fetch the string from the new image.
         */
        if (Lsp->pr_why == PR_SYSEXIT && what == SYS_execve) {
            psinfo_t psinfo;
            long argv;
            auxv_t auxv[32];
            int naux;

            offset = 0;
            naux = proc_get_auxv(pid, auxv, 32);
            for (i = 0; i < naux; i++) {
                if (auxv[i].a_type == AT_SUN_EXECNAME) {
                    offset = (long)auxv[i].a_un.a_ptr;
                    break;
                }
            }
            if (offset == 0 &&
                proc_get_psinfo(pid, &psinfo) == 0) {
                argv = (long)psinfo.pr_argv;
                if (data_model == PR_MODEL_LP64)
                    (void) Pread(Proc, &offset,
                        sizeof (offset), argv);
                else {
                    offset32 = 0;
                    (void) Pread(Proc, &offset32,
                        sizeof (offset32), argv);
                    offset = offset32;
                }
            }
        } else if (stp->arg[0] == STG) {
            offset = pri->sys_args[0];
        } else {
            offset = pri->sys_args[1];
        }
        if ((s = fetchstring(pri, offset, PATH_MAX)) != NULL) {
            pri->sys_valid = TRUE;
            len = strlen(s);
            /* reallocate if necessary */
            while (len >= pri->sys_psize) {
                free(pri->sys_path);
                pri->sys_path = my_malloc(pri->sys_psize *= 2,
                    "pathname buffer");
            }
            (void) strcpy(pri->sys_path, s); /* remember pathname */
        }
    }

    istraced = dotrace && prismember(&trace, what);
    raw = prismember(&rawout, what);

    /* force tracing of read/write buffer dump syscalls */
    if (!istraced && nargs > 2) {
        int fdp1 = (int)pri->sys_args[0] + 1;

        if (ISREAD(what)) {
            if (prismember(&readfd, fdp1))
                istraced = TRUE;
        } else if (ISWRITE(what)) {
            if (prismember(&writefd, fdp1))
                istraced = TRUE;
        }
    }

    pri->sys_leng = 0;
    if (cflag || !istraced)     /* just counting */
        *pri->sys_string = 0;
    else {
        int argprinted = FALSE;
        const char *name;

        name = sysname(pri, what, raw? -1 : subcode);
        grow(pri, strlen(name) + 1);
        pri->sys_leng = snprintf(pri->sys_string, pri->sys_ssize,
            "%s(", name);
        for (i = 0; i < nargs; i++) {
            arg = pri->sys_args[i];
            x = stp->arg[i];

            if (!raw && pri->sys_valid &&
                ((i == 0 && x == STG) ||
                (i == 1 && (what == SYS_openat ||
                what == SYS_openat64)))) {  /* already fetched */
                if (argprinted)
                    outstring(pri, ", ");
                escape_string(pri, pri->sys_path);
                argprinted = TRUE;
            } else if (x != NOV && (x != HID || raw)) {
                if (argprinted)
                    outstring(pri, ", ");
                if (x == LLO)
                    (*Print[x])(pri, raw, arg,
                        pri->sys_args[++i]);
                else
                    (*Print[x])(pri, raw, arg);
                argprinted = TRUE;
            }
        }
        outstring(pri, ")");
    }

    return (istraced);
}
#undef  ISREAD
#undef  ISWRITE

/*
 * sysexit() returns non-zero if anything was printed.
 */
int
sysexit(private_t *pri, int dotrace)
{
    const lwpstatus_t *Lsp = pri->lwpstat;
    int what = Lsp->pr_what;
    struct syscount *scp;
    const struct systable *stp;
    int subcode;
    int istraced;
    int raw;

    /* protect ourself from operating system error */
    if (what <= 0 || what > PRMAXSYS)
        return (0);

    /*
     * If we aren't supposed to be tracing this one, then
     * delete it from the traced signal set.  We got here
     * because the process was sleeping in an untraced syscall.
     */
    if (!prismember(&traceeven, what)) {
        (void) Psysexit(Proc, what, FALSE);
        return (0);
    }

    /* pick up registers & set pri->Errno before anything else */
    pri->Errno = Lsp->pr_errno;
    pri->ErrPriv = Lsp->pr_errpriv;
    pri->Rval1 = Lsp->pr_rval1;
    pri->Rval2 = Lsp->pr_rval2;

    switch (what) {
    case SYS_exit:      /* these are traced on entry */
    case SYS_lwp_exit:
    case SYS_context:
        istraced = dotrace && prismember(&trace, what);
        break;
    case SYS_execve:    /* this is normally traced on entry */
        istraced = dotrace && prismember(&trace, what);
        if (pri->exec_string && *pri->exec_string) {
            if (!cflag && istraced) { /* print exec() string now */
                if (pri->exec_pname[0] != '\0')
                    (void) fputs(pri->exec_pname, stdout);
                timestamp(pri);
                (void) fputs(pri->exec_string, stdout);
            }
            pri->exec_pname[0] = '\0';
            pri->exec_string[0] = '\0';
            break;
        }
        /* FALLTHROUGH */
    default:
        /* we called sysentry() in main() for these */
        if (what == SYS_openat || what == SYS_openat64 ||
            what == SYS_open || what == SYS_open64)
            istraced = dotrace && prismember(&trace, what);
        else
            istraced = sysentry(pri, dotrace) && dotrace;
        pri->length = 0;
        if (!cflag && istraced) {
            putpname(pri);
            timestamp(pri);
            pri->length += printf("%s", pri->sys_string);
        }
        pri->sys_leng = 0;
        *pri->sys_string = '\0';
        break;
    }

    /* get systable entry for this syscall */
    subcode = getsubcode(pri);
    stp = subsys(what, subcode);

    if (cflag && istraced) {
        (void) mutex_lock(&count_lock);
        scp = Cp->syscount[what];
        if (what == SYS_forksys && subcode >= 3)
            scp += subcode - 3;
        else if (subcode != -1 &&
            (what != SYS_openat && what != SYS_openat64 &&
            what != SYS_open && what != SYS_open64 &&
            what != SYS_lwp_create))
            scp += subcode;
        scp->count++;
        accumulate(&scp->stime, &Lsp->pr_stime, &pri->syslast);
        accumulate(&Cp->usrtotal, &Lsp->pr_utime, &pri->usrlast);
        pri->syslast = Lsp->pr_stime;
        pri->usrlast = Lsp->pr_utime;
        (void) mutex_unlock(&count_lock);
    }

    raw = prismember(&rawout, what);

    if (!cflag && istraced) {
        if ((what == SYS_vfork || what == SYS_forksys) &&
            pri->Errno == 0 && pri->Rval2 != 0) {
            pri->length &= ~07;
            if (strlen(sysname(pri, what, raw? -1 : subcode)) < 6) {
                (void) fputc('\t', stdout);
                pri->length += 8;
            }
            pri->length +=
                7 + printf("\t(returning as child ...)");
        }
        if (what == SYS_lwp_create &&
            pri->Errno == 0 && pri->Rval1 == 0) {
            pri->length &= ~07;
            pri->length +=
                7 + printf("\t(returning as new lwp ...)");
        }
        if (pri->Errno != 0 || what != SYS_execve) {
            /* prepare to print the return code */
            pri->length >>= 3;
            if (pri->length >= 6)
                (void) fputc(' ', stdout);
            for (; pri->length < 6; pri->length++)
                (void) fputc('\t', stdout);
        }
    }
    pri->length = 0;

    if (pri->Errno != 0) {      /* error in syscall */
        if (istraced) {
            if (cflag)
                scp->error++;
            else {
                const char *ename = errname(pri->Errno);
                const char *privname;

                (void) printf("Err#%d", pri->Errno);
                if (ename != NULL) {
                    (void) fputc(' ', stdout);
                    (void) fputs(ename, stdout);
                }
                switch (pri->ErrPriv) {
                case PRIV_NONE:
                    privname = NULL;
                    break;
                case PRIV_ALL:
                    privname = "ALL";
                    break;
                case PRIV_MULTIPLE:
                    privname = "MULTIPLE";
                    break;
                case PRIV_ALLZONE:
                    privname = "ZONE";
                    break;
                default:
                    privname = priv_getbynum(pri->ErrPriv);
                    break;
                }
                if (privname != NULL)
                    (void) printf(" [%s]", privname);

                (void) fputc('\n', stdout);
            }
        }
    } else {
        /* show arguments on successful exec */
        if (what == SYS_execve) {
            if (!cflag && istraced)
                showargs(pri, raw);
        } else if (!cflag && istraced) {
            const char *fmt = NULL;
            long rv1 = pri->Rval1;
            long rv2 = pri->Rval2;

#ifdef _LP64
            /*
             * 32-bit system calls return 32-bit values. We
             * later mask out the upper bits if we want to
             * print these as unsigned values.
             */
            if (data_model == PR_MODEL_ILP32) {
                rv1 = (int)rv1;
                rv2 = (int)rv2;
            }
#endif

            switch (what) {
            case SYS_llseek:
                rv1 &= 0xffffffff;
                rv2 &= 0xffffffff;
#ifdef _LONG_LONG_LTOH  /* first long of a longlong is the low order */
                if (rv2 != 0) {
                    long temp = rv1;
                    fmt = "= 0x%lX%.8lX";
                    rv1 = rv2;
                    rv2 = temp;
                    break;
                }
#else   /* the other way around */
                if (rv1 != 0) {
                    fmt = "= 0x%lX%.8lX";
                    break;
                }
                rv1 = rv2;  /* ugly */
#endif
                /* FALLTHROUGH */
            case SYS_lseek:
            case SYS_ulimit:
                if (rv1 & 0xff000000) {
#ifdef _LP64
                    if (data_model == PR_MODEL_ILP32)
                        rv1 &= 0xffffffff;
#endif
                    fmt = "= 0x%.8lX";
                }
                break;
            case SYS_sigtimedwait:
                if (raw)
                    /* EMPTY */;
                else if ((fmt = rawsigname(pri, rv1)) != NULL) {
                    rv1 = (long)fmt;    /* filthy */
                    fmt = "= %s";
                }
                break;
            case SYS_port:
#ifdef _LP64
                if (data_model == PR_MODEL_LP64) {
                    rv2 = rv1 & 0xffffffff;
                    rv1 = rv1 >> 32;
                }
#endif
                break;
            }

            if (fmt == NULL) {
                switch (stp->rval[0]) {
                case HEX:
#ifdef _LP64
                    if (data_model == PR_MODEL_ILP32)
                        rv1 &= 0xffffffff;
#endif
                    fmt = "= 0x%.8lX";
                    break;
                case HHX:
#ifdef _LP64
                    if (data_model == PR_MODEL_ILP32)
                        rv1 &= 0xffffffff;
#endif
                    fmt = "= 0x%.4lX";
                    break;
                case OCT:
#ifdef _LP64
                    if (data_model == PR_MODEL_ILP32)
                        rv1 &= 0xffffffff;
#endif
                    fmt = "= %#lo";
                    break;
                case UNS:
#ifdef _LP64
                    if (data_model == PR_MODEL_ILP32)
                        rv1 &= 0xffffffff;
#endif
                    fmt = "= %lu";
                    break;
                default:
                    fmt = "= %ld";
                    break;
                }
            }

            (void) printf(fmt, rv1, rv2);

            switch (stp->rval[1]) {
            case NOV:
                fmt = NULL;
                break;
            case HEX:
#ifdef _LP64
                if (data_model == PR_MODEL_ILP32)
                    rv2 &= 0xffffffff;
#endif
                fmt = " [0x%.8lX]";
                break;
            case HHX:
#ifdef _LP64
                if (data_model == PR_MODEL_ILP32)
                    rv2 &= 0xffffffff;
#endif
                fmt = " [0x%.4lX]";
                break;
            case OCT:
#ifdef _LP64
                if (data_model == PR_MODEL_ILP32)
                    rv2 &= 0xffffffff;
#endif
                fmt = " [%#lo]";
                break;
            case UNS:
#ifdef _LP64
                if (data_model == PR_MODEL_ILP32)
                    rv2 &= 0xffffffff;
#endif
                fmt = " [%lu]";
                break;
            default:
                fmt = " [%ld]";
                break;
            }

            if (fmt != NULL)
                (void) printf(fmt, rv2);
            (void) fputc('\n', stdout);
        }

        if (what == SYS_vfork || what == SYS_forksys) {
            if (pri->Rval2 == 0)        /* child was created */
                pri->child = pri->Rval1;
            else if (cflag && istraced) /* this is the child */
                scp->count--;
        }
        if (what == SYS_lwp_create && pri->Rval1 == 0 &&
            cflag && istraced)      /* this is the created lwp */
            scp->count--;
    }

#define ISREAD(code) \
    ((code) == SYS_read || (code) == SYS_pread || (code) == SYS_pread64 || \
    (code) == SYS_recv || (code) == SYS_recvfrom)
#define ISWRITE(code) \
    ((code) == SYS_write || (code) == SYS_pwrite || \
    (code) == SYS_pwrite64 || (code) == SYS_send || (code) == SYS_sendto)

    if (!cflag && istraced) {
        int fdp1 = (int)pri->sys_args[0] + 1; /* filedescriptor + 1 */

        if (raw) {
            if (what != SYS_execve)
                showpaths(pri, stp);
            if (ISREAD(what) || ISWRITE(what)) {
                if (pri->iob_buf[0] != '\0')
                    (void) printf("%s     0x%.8lX: %s\n",
                        pri->pname, pri->sys_args[1],
                        pri->iob_buf);
            }
        }

        /*
         * Show buffer contents for read()/pread() or write()/pwrite().
         * IOBSIZE bytes have already been shown;
         * don't show them again unless there's more.
         */
        if ((ISREAD(what) && pri->Errno == 0 &&
            prismember(&readfd, fdp1)) ||
            (ISWRITE(what) && prismember(&writefd, fdp1))) {
            long nb = ISWRITE(what) ? pri->sys_args[2] : pri->Rval1;

            if (nb > IOBSIZE) {
                /* enter region of lengthy output */
                if (nb > MYBUFSIZ / 4)
                    Eserialize();

                showbuffer(pri, pri->sys_args[1], nb);

                /* exit region of lengthy output */
                if (nb > MYBUFSIZ / 4)
                    Xserialize();
            }
        }
#undef  ISREAD
#undef  ISWRITE
        /*
         * Do verbose interpretation if requested.
         * If buffer contents for read or write have been requested and
         * this is a readv() or writev(), force verbose interpretation.
         */
        if (prismember(&verbose, what) ||
            ((what == SYS_readv || what == SYS_recvmsg) &&
            pri->Errno == 0 && prismember(&readfd, fdp1)) ||
            ((what == SYS_writev || what == SYS_sendfilev ||
            what == SYS_sendmsg) &&
            prismember(&writefd, fdp1)))
            expound(pri, pri->Rval1, raw);
    }

    return (!cflag && istraced);
}

void
showpaths(private_t *pri, const struct systable *stp)
{
    int what = pri->lwpstat->pr_what;
    int i;

    for (i = 0; i < pri->sys_nargs; i++) {
        if (stp->arg[i] == ATC && (int)pri->sys_args[i] == AT_FDCWD) {
            (void) printf("%s     0x%.8X: AT_FDCWD\n",
                pri->pname, AT_FDCWD);
        } else if ((stp->arg[i] == STG) ||
            (stp->arg[i] == RST && !pri->Errno) ||
            (stp->arg[i] == RLK && !pri->Errno && pri->Rval1 > 0)) {
            long addr = pri->sys_args[i];
            int maxleng =
                (stp->arg[i] == RLK)? (int)pri->Rval1 : PATH_MAX;
            char *s;

            if (pri->sys_valid &&
                ((i == 0 && stp->arg[0] == STG) ||
                (i == 1 && (what == SYS_openat ||
                what == SYS_openat64))))    /* already fetched */
                s = pri->sys_path;
            else
                s = fetchstring(pri, addr,
                    maxleng > PATH_MAX ? PATH_MAX : maxleng);

            if (s != (char *)NULL)
                (void) printf("%s     0x%.8lX: \"%s\"\n",
                    pri->pname, addr, s);
        }
    }
}

/*
 * Display arguments to successful exec().
 */
void
showargs(private_t *pri, int raw)
{
    const lwpstatus_t *Lsp = pri->lwpstat;
    int nargs;
    long ap;
    int ptrsize;
    int fail;

    pri->length = 0;
    ptrsize = (data_model == PR_MODEL_LP64)? 8 : 4;

#if defined(__i386) || defined(__amd64) /* XX64 */
    ap = (long)Lsp->pr_reg[R_SP];
    fail = (Pread(Proc, &nargs, sizeof (nargs), ap) != sizeof (nargs));
    ap += ptrsize;
#endif /* i386 */

#if sparc
    if (data_model == PR_MODEL_LP64) {
        int64_t xnargs;
        ap = (long)(Lsp->pr_reg[R_SP]) + 16 * sizeof (int64_t)
            + STACK_BIAS;
        fail = (Pread(Proc, &xnargs, sizeof (xnargs), ap) !=
            sizeof (xnargs));
        nargs = (int)xnargs;
    } else {
        ap = (long)(Lsp->pr_reg[R_SP]) + 16 * sizeof (int32_t);
        fail = (Pread(Proc, &nargs, sizeof (nargs), ap) !=
            sizeof (nargs));
    }
    ap += ptrsize;
#endif /* sparc */

    if (fail) {
        (void) printf("\n%s\t*** Bad argument list? ***\n", pri->pname);
        return;
    }

    (void) printf("  argc = %d\n", nargs);
    if (raw)
        showpaths(pri, &systable[SYS_execve]);

    show_cred(pri, FALSE, FALSE);

    if (aflag || eflag) {       /* dump args or environment */

        /* enter region of (potentially) lengthy output */
        Eserialize();

        if (aflag)      /* dump the argument list */
            dumpargs(pri, ap, "argv:");
        ap += (nargs+1) * ptrsize;
        if (eflag)      /* dump the environment */
            dumpargs(pri, ap, "envp:");

        /* exit region of lengthy output */
        Xserialize();
    }
}

void
dumpargs(private_t *pri, long ap, const char *str)
{
    char *string;
    unsigned int leng = 0;
    int ptrsize;
    long arg = 0;
    char *argaddr;
    char badaddr[32];

    if (interrupt)
        return;

#ifdef _LP64
    if (data_model == PR_MODEL_LP64) {
        argaddr = (char *)&arg;
        ptrsize = 8;
    } else {
#if defined(_LITTLE_ENDIAN)
        argaddr = (char *)&arg;
#else
        argaddr = (char *)&arg + 4;
#endif
        ptrsize = 4;
    }
#else
    argaddr = (char *)&arg;
    ptrsize = 4;
#endif
    putpname(pri);
    (void) fputc(' ', stdout);
    (void) fputs(str, stdout);
    leng += 1 + strlen(str);

    while (!interrupt) {
        if (Pread(Proc, argaddr, ptrsize, ap) != ptrsize) {
            (void) printf("\n%s\t*** Bad argument list? ***\n",
                pri->pname);
            return;
        }
        ap += ptrsize;

        if (arg == 0)
            break;
        string = fetchstring(pri, arg, PATH_MAX);
        if (string == NULL) {
            (void) sprintf(badaddr, "BadAddress:0x%.8lX", arg);
            string = badaddr;
        }
        if ((leng += strlen(string)) < 63) {
            (void) fputc(' ', stdout);
            leng++;
        } else {
            (void) fputc('\n', stdout);
            leng = 0;
            putpname(pri);
            (void) fputs("  ", stdout);
            leng += 2 + strlen(string);
        }
        (void) fputs(string, stdout);
    }
    (void) fputc('\n', stdout);
}

/*
 * Display contents of read() or write() buffer.
 */
void
showbuffer(private_t *pri, long offset, long count)
{
    char buffer[320];
    int nbytes;
    char *buf;
    int n;

    while (count > 0 && !interrupt) {
        nbytes = (count < sizeof (buffer))? count : sizeof (buffer);
        if ((nbytes = Pread(Proc, buffer, nbytes, offset)) <= 0)
            break;
        count -= nbytes;
        offset += nbytes;
        buf = buffer;
        while (nbytes > 0 && !interrupt) {
            char obuf[65];

            n = (nbytes < 32)? nbytes : 32;
            showbytes(buf, n, obuf);

            putpname(pri);
            (void) fputs("  ", stdout);
            (void) fputs(obuf, stdout);
            (void) fputc('\n', stdout);
            nbytes -= n;
            buf += n;
        }
    }
}

void
showbytes(const char *buf, int n, char *obuf)
{
    int c;

    while (--n >= 0) {
        int c1 = '\\';
        int c2;

        switch (c = (*buf++ & 0xff)) {
        case '\0':
            c2 = '0';
            break;
        case '\b':
            c2 = 'b';
            break;
        case '\t':
            c2 = 't';
            break;
        case '\n':
            c2 = 'n';
            break;
        case '\v':
            c2 = 'v';
            break;
        case '\f':
            c2 = 'f';
            break;
        case '\r':
            c2 = 'r';
            break;
        default:
            if (isprint(c)) {
                c1 = ' ';
                c2 = c;
            } else {
                c1 = c>>4;
                c1 += (c1 < 10)? '0' : 'A'-10;
                c2 = c&0xf;
                c2 += (c2 < 10)? '0' : 'A'-10;
            }
            break;
        }
        *obuf++ = (char)c1;
        *obuf++ = (char)c2;
    }

    *obuf = '\0';
}