ptools/psig/psig.c

	psig.c revision 7c478bd95313f5f23a4c958a745db2134aa03244
/*
 * CDDL HEADER START
 *
 * The contents of this file are subject to the terms of the
 * Common Development and Distribution License, Version 1.0 only
 * (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 2004 Sun Microsystems, Inc.  All rights reserved.
 * Use is subject to license terms.
 */

#pragma ident   "%Z%%M% %I% %E% SMI"

#include <stdio.h>
#include <stdlib.h>
#include <unistd.h>
#include <ctype.h>
#include <fcntl.h>
#include <string.h>
#include <signal.h>
#include <stddef.h>
#include <sys/types.h>
#include <sys/stat.h>
#include <libproc.h>

/* evil knowledge of libc internals */
#include "../../../lib/libc/inc/thr_uberdata.h"

#define MAX_SYMNAMLEN   1024    /* Recommended max symbol name length */

static  char    *sigflags(int, int);
static  int look(char *);
static  void    perr(char *);
static  int usage(void);
static  uintptr_t deinterpose(int, void *, psinfo_t *, struct sigaction *);

static  char    *command;
static  char    *procname;
static  int all_flag = 0;
static  int lookuphandlers_flag = 1;

int
main(int argc, char **argv)
{
    int rc = 0;
    int c;
    struct rlimit rlim;

    if ((command = strrchr(argv[0], '/')) != NULL)
        command++;
    else
        command = argv[0];

    while ((c = getopt(argc, argv, "an")) != EOF) {
        switch (c) {
        case 'a':
            all_flag = 1;
            break;
        case 'n':
            lookuphandlers_flag = 0;
            break;
        default:
            return (usage());
        }
    }

    if (argc - optind < 1) {
        return (usage());
    }

    /*
     * Make sure we'll have enough file descriptors to handle a target
     * that has many many mappings.
     */
    if (getrlimit(RLIMIT_NOFILE, &rlim) == 0) {
        rlim.rlim_cur = rlim.rlim_max;
        (void) setrlimit(RLIMIT_NOFILE, &rlim);
    }

    for (; optind != argc; optind++) {
        rc += look(argv[optind]);
    }

    return (rc);
}

static int
usage(void)
{
    (void) fprintf(stderr, "usage:\t%s [-n] pid ...\n", command);
    (void) fprintf(stderr, "  (report process signal actions)\n");

    return (2);
}

static uintptr_t
uberdata_addr(struct ps_prochandle *Pr, char dmodel)
{
    GElf_Sym sym;

    if (Plookup_by_name(Pr, "libc.so", "_tdb_bootstrap", &sym) < 0)
        return (NULL);
#ifdef _LP64
    if (dmodel != PR_MODEL_NATIVE) {
        caddr32_t uaddr;
        caddr32_t addr;

        if (Pread(Pr, &addr, sizeof (addr), sym.st_value)
            == sizeof (addr) &&
            addr != 0 &&
            Pread(Pr, &uaddr, sizeof (uaddr), (uintptr_t)addr)
            == sizeof (uaddr) &&
            uaddr != 0)
            return ((uintptr_t)uaddr);
    }
#endif
    if (dmodel == PR_MODEL_NATIVE) {
        uintptr_t uaddr;
        uintptr_t addr;

        if (Pread(Pr, &addr, sizeof (addr), sym.st_value)
            == sizeof (addr) &&
            addr != 0 &&
            Pread(Pr, &uaddr, sizeof (uaddr), addr)
            == sizeof (uaddr) &&
            uaddr != 0)
            return (uaddr);
    }
    if (Plookup_by_name(Pr, "libc.so", "_uberdata", &sym) < 0)
        return (0);
    return (sym.st_value);
}

/*
 * Iterator function used to generate the process sigmask
 * from the individual lwp sigmasks.
 */
static int
lwp_iter(void *cd, const lwpstatus_t *lwpstatus)
{
    sigset_t *ssp = cd;

    ssp->__sigbits[0] &= lwpstatus->pr_lwphold.__sigbits[0];
    ssp->__sigbits[1] &= lwpstatus->pr_lwphold.__sigbits[1];
    ssp->__sigbits[2] &= lwpstatus->pr_lwphold.__sigbits[2];
    ssp->__sigbits[3] &= lwpstatus->pr_lwphold.__sigbits[3];

    /*
     * Return non-zero to terminate the iteration
     * if the sigmask has become all zeros.
     */
    return ((ssp->__sigbits[0] | ssp->__sigbits[1] |
        ssp->__sigbits[2] | ssp->__sigbits[3]) == 0);
}

static int
look(char *arg)
{
    char pathname[100];
    struct stat statb;
    int fd = -1;
    int sig, gcode;
    sigset_t holdmask;
    int maxsig;
    struct sigaction *action = NULL;
    psinfo_t psinfo;
    const psinfo_t *psinfop;
    struct ps_prochandle *Pr = NULL;
    uintptr_t uberaddr;
    uintptr_t aharraddr;
    uintptr_t intfnaddr;
    size_t aharrlen;
    void *aharr = NULL;
    int error = 1;

    procname = arg;     /* for perr() */
    if ((Pr = proc_arg_grab(arg, PR_ARG_PIDS, PGRAB_RDONLY|PGRAB_FORCE,
        &gcode)) == NULL || (psinfop = Ppsinfo(Pr)) == NULL) {
        (void) fprintf(stderr, "%s: cannot examine %s: %s\n",
            command, arg, Pgrab_error(gcode));
        goto look_error;
    }
    (void) memcpy(&psinfo, psinfop, sizeof (psinfo_t));
    proc_unctrl_psinfo(&psinfo);

    (void) sprintf(pathname, "/proc/%d/sigact", (int)psinfo.pr_pid);
    if ((fd = open(pathname, O_RDONLY)) < 0) {
        perr("open sigact");
        goto look_error;
    }

    if (fstat(fd, &statb) != 0) {
        perr("fstat sigact");
        goto look_error;
    }
    maxsig = statb.st_size / sizeof (struct sigaction);
    action = malloc(maxsig * sizeof (struct sigaction));
    if (action == NULL) {
        (void) fprintf(stderr,
        "%s: cannot malloc() space for %d sigaction structures\n",
            command, maxsig);
        goto look_error;
    }
    if (read(fd, (char *)action, maxsig * sizeof (struct sigaction)) !=
        maxsig * sizeof (struct sigaction)) {
        perr("read sigact");
        goto look_error;
    }
    (void) close(fd);
    fd = -1;

    (void) printf("%d:\t%.70s\n", (int)psinfo.pr_pid, psinfo.pr_psargs);

    (void) sigfillset(&holdmask);
    (void) Plwp_iter(Pr, lwp_iter, &holdmask);

    if ((uberaddr = uberdata_addr(Pr, psinfo.pr_dmodel)) == 0) {
        aharraddr = 0;
        aharrlen = 0;
        intfnaddr = 0;
    } else {
#ifdef _LP64
        if (psinfo.pr_dmodel != PR_MODEL_NATIVE) {
            caddr32_t addr;
            aharraddr = uberaddr +
                offsetof(uberdata32_t, siguaction);
            aharrlen = sizeof (siguaction32_t) * NSIG;
            (void) Pread(Pr, &addr, sizeof (addr),
                uberaddr + offsetof(uberdata32_t, sigacthandler));
            intfnaddr = (uintptr_t)addr;
        } else
#endif
        {
            aharraddr = uberaddr +
                offsetof(uberdata_t, siguaction);
            aharrlen = sizeof (siguaction_t) * NSIG;
            (void) Pread(Pr, &intfnaddr, sizeof (intfnaddr),
                uberaddr + offsetof(uberdata_t, sigacthandler));
        }
    }

    if (aharraddr) {
        aharr = malloc(aharrlen);
        if (aharr == NULL) {
            (void) fprintf(stderr,
            "%s: cannot malloc() space for actual handler array\n",
                command);
            goto look_error;
        }

        if (Pread(Pr, aharr, aharrlen, aharraddr) != aharrlen) {
            (void) fprintf(stderr,
                "%s: signal handler data at %p cannot be read.\n",
                command, (void *)aharraddr);
            free(aharr);
            aharr = NULL;
        }
    }

    for (sig = 1; sig <= maxsig; sig++) {
        struct sigaction *sp = &action[sig - 1];
        int caught = 0;
        char buf[SIG2STR_MAX];
        char *s;

        /* proc_signame() returns "SIG..."; skip the "SIG" part */
        (void) printf("%s\t", proc_signame(sig, buf, sizeof (buf)) + 3);

        if (prismember(&holdmask, sig))
            (void) printf("blocked,");

        if (sp->sa_handler == SIG_DFL)
            (void) printf("default");
        else if (sp->sa_handler == SIG_IGN)
            (void) printf("ignored");
        else
            caught = 1;

        if (caught || all_flag) {
            uintptr_t haddr;
            GElf_Sym hsym;
            char hname[MAX_SYMNAMLEN];
            char buf[PRSIGBUFSZ];

            haddr = (uintptr_t)sp->sa_handler;

            if (aharr && intfnaddr && haddr == intfnaddr)
                haddr = deinterpose(sig, aharr, &psinfo, sp);

            if (haddr == (uintptr_t)SIG_DFL) {
                if (caught)
                    (void) printf("default");
                caught = 0;
            } else if (haddr == (uintptr_t)SIG_IGN) {
                if (caught)
                    (void) printf("ignored");
                caught = 0;
            } else {
                if (caught)
                    (void) printf("caught");
            }

            if (caught || all_flag) {
                if (lookuphandlers_flag && haddr > 1 &&
                    Plookup_by_addr(Pr, haddr, hname,
                    sizeof (hname), &hsym) == 0)
                    (void) printf("\t%-8s", hname);
                else
                    (void) printf("\t0x%-8lx",
                        (ulong_t)haddr);

                s = sigflags(sig, sp->sa_flags);
                (void) printf("%s", (*s != '\0')? s : "\t0");
                (void) proc_sigset2str(&sp->sa_mask, ",", 1,
                    buf, sizeof (buf));
                if (buf[0] != '\0')
                    (void) printf("\t%s", buf);
            }
        } else if (sig == SIGCLD) {
            s = sigflags(sig,
                sp->sa_flags & (SA_NOCLDWAIT|SA_NOCLDSTOP));
            if (*s != '\0')
                (void) printf("\t\t%s", s);
        }
        (void) printf("\n");
    }

    error = 0;

look_error:
    if (fd >= 0)
        (void) close(fd);
    if (aharr)
        free(aharr);
    if (action)
        free(action);
    if (Pr)
        Prelease(Pr, 0);
    return (error);
}

static void
perr(char *s)
{
    if (s)
        (void) fprintf(stderr, "%s: ", procname);
    else
        s = procname;
    perror(s);
}

static char *
sigflags(int sig, int flags)
{
    static char code_buf[100];
    char *str = code_buf;
    int flagmask =
        (SA_ONSTACK|SA_RESETHAND|SA_RESTART|SA_SIGINFO|SA_NODEFER);

    if (sig == SIGCLD)
        flagmask |= (SA_NOCLDSTOP|SA_NOCLDWAIT);

    *str = '\0';
    if (flags & ~flagmask)
        (void) sprintf(str, ",0x%x,", flags & ~flagmask);
    else if (flags == 0)
        return (str);

    if (flags & SA_RESTART)
        (void) strcat(str, ",RESTART");
    if (flags & SA_RESETHAND)
        (void) strcat(str, ",RESETHAND");
    if (flags & SA_ONSTACK)
        (void) strcat(str, ",ONSTACK");
    if (flags & SA_SIGINFO)
        (void) strcat(str, ",SIGINFO");
    if (flags & SA_NODEFER)
        (void) strcat(str, ",NODEFER");

    if (sig == SIGCLD) {
        if (flags & SA_NOCLDWAIT)
            (void) strcat(str, ",NOCLDWAIT");
        if (flags & SA_NOCLDSTOP)
            (void) strcat(str, ",NOCLDSTOP");
    }

    *str = '\t';

    return (str);
}

/*ARGSUSED2*/
static uintptr_t
deinterpose(int sig, void *aharr, psinfo_t *psinfo, struct sigaction *sp)
{
    if (sp->sa_handler == SIG_DFL || sp->sa_handler == SIG_IGN)
        return ((uintptr_t)sp->sa_handler);
#ifdef _LP64
    if (psinfo->pr_dmodel != PR_MODEL_NATIVE) {
        struct sigaction32 *sa32 = (struct sigaction32 *)
            ((uintptr_t)aharr + sig * sizeof (siguaction32_t) +
            offsetof(siguaction32_t, sig_uaction));

        sp->sa_flags = sa32->sa_flags;
        sp->sa_handler = (void (*)())(uintptr_t)sa32->sa_handler;
        (void) memcpy(&sp->sa_mask, &sa32->sa_mask,
            sizeof (sp->sa_mask));
    } else
#endif
    {
        struct sigaction *sa = (struct sigaction *)
            ((uintptr_t)aharr + sig * sizeof (siguaction_t) +
            offsetof(siguaction_t, sig_uaction));

        sp->sa_flags = sa->sa_flags;
        sp->sa_handler = sa->sa_handler;
        sp->sa_mask = sa->sa_mask;
    }
    return ((uintptr_t)sp->sa_handler);
}